US20030152331A1

US20030152331A1 - Methods and apparatus for fiber-optic modules with shielded housing/covers having mixed finger types

Info

Publication number: US20030152331A1
Application number: US10/335,443
Authority: US
Inventors: Edwin Dair; Wenbin Jiang; Cheng Wei; Yong Sim
Original assignee: Edwin Dair; Wenbin Jiang; Wei Cheng Ping; Sim Yong Peng
Current assignee: Viavi Solutions Inc
Priority date: 2001-02-12
Filing date: 2002-12-31
Publication date: 2003-08-14
Also published as: US6607308B2; US20030152339A1; US20020110338A1

Abstract

A fiber-optic module having a housing/shielding unit and a module chassis frame having optical, electrical and electro-optical components. The housing/shielding unit functions both as a protective outer housing and an electromagnetic shield. The housing/shielding unit includes forward fingers and backward fingers. The forward fingers provide an EMI seal around an opening in a bezel, face-plate, back-plate, wall, or panel of a host system and thereby can ground the housing/shielding unit to a chassis ground. The backward fingers can contact host tabs of the host system and can also thereby ground the housing/shielding unit to a chassis ground. The module chassis frame may be formed of a conductive material and can be grounded as well through a host system faceplate or otherwise to the chassis ground.

Description

CROSS REFERENCE TO RELATED APPLICATION

This United States non-provisional patent application claims the benefit and is a continuation-in-part of U.S. patent application Ser. No. 09/782,875, filed on Feb. 12, 2001 by Dair et al. having Attorney Docket No. 003918.P014, both of which are to be assigned to E2O Communications, Inc.[0001]

FIELD OF THE INVENTION

The invention relates to electromagnetic shielding, and more specifically, to electromagnetic shielding of fiber-optic modules.

BACKGROUND OF THE INVENTION

As the need for greater data bandwidth over networks has exploded over the past few years, there has been a move towards using optical fibers as a transmission medium. Today, optical fiber made of dielectric materials are routinely used in communication channels from large public transmission media to Local Area Networks transmitting information from one node to another. The main difference between a fiber-optic communication system and other types of communication systems is that signals are transmitted as light or photons over optical fibers. Optical fiber or fiber-optic cables enable high speed communication of signals by guiding light or photons therein. At each end of a fiber-optic cable a transducer may be found that converts a light, photon or optical signal into an electrical signal; an electrical signal into a light, photon or optical signal; or a pair of transducers may do both. At a transmission end, an electrical-to-optical converter (EO) converts electrical signals into light or optical signals. At a receiving end, an optical-to-electrical converter (OE) converts a light, photon or optical signal into an electrical signal. In nodes of a communication system, it may be desirable to both transmit and receive light or optical signals at a node. In which case an optical-to-electrical converter (OE, i.e. receiver) and an electrical-to-optical converter (EO, i.e. transmitter) may be included to receive and transmit optical or light signals respectively. Therefore, the optical-to-electrical converter (OE, i.e. receiver) and the electrical-to-optical converter (EO, i.e. transmitter) are oftentimes physically located together as a single module referred to as an electro-optic, opto-electronic or fiber-optic transceiver. Fiber-optic transceivers, including fiber-optic transmitters and fiber-optic receivers, can also be referred to as fiber-optic modules.

Because of the high frequency needed in some of the electronics and the electro-optic components, such as the optical-to-electrical converter (OE, i.e. receiver) and electrical-to-optical converter (EO, i.e. transmitter), electromagnetic radiation can be generated which can interfere with other communication systems. This electromagnetic radiation is oftentimes referred to as electromagnetic interference (EMI). Electromagnetic radiation radiating externally out from a fiber-optic module or a system that incorporates the fiber-optic module is of great concern. To reduce electromagnetic radiation from radiating out of fiber-optic modules and systems with fiber optic modules as EMI, external electromagnetic shielding of internal electronic and opto-electronic components is often utilized. The external electromagnetic shielding can additionally reduce effects of external electromagnetic radiation on the internal components of a fiber-optic module and the system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear isometric view of the fiber-optic module according to a first embodiment of the invention [0005]
FIG. 2 is a front isometric view of the fiber-optic module according to the first embodiment of the invention [0006]
FIG. 3 is a rear isometric view of a housing/shielding unit according to the first embodiment of the invention. [0007]
FIG. 4A is a bottom rear isometric view of the housing/shielding unit according to the first embodiment of the invention. [0008]
FIG. 4B is a bottom rear isometric view of an alternate housing/shielding unit according to an alternate embodiment of the invention. [0009]
FIG. 5A is an isometric view of a module chassis frame and a housing/shielding unit according to the first embodiment of the invention. [0010]
FIG. 5B is an isometric view of a module chassis frame and a housing/shielding unit according to an alternate embodiment of the invention. [0011]
FIG. 6 is an exploded view of the fiber-optic module with the housing/shielding unit and the module chassis frame according to the first embodiment of the invention. [0012]
FIG. 7 is an isometric view of a module chassis frame and a housing/shielding unit for an fiber-optic module according to a second embodiment of the invention. [0013]
FIG. 8A is a front isometric view of a housing/shielding unit according to the second embodiment of the invention. [0014]
FIG. 8B is a front isometric view of an alternate housing/shielding unit according to an alternate embodiment of the invention. [0015]
FIG. 9A is a bottom isometric view of the housing/shielding unit according to the second embodiment of the invention. [0016]
FIG. 9B is a bottom rear isometric view of an alternate housing/shielding unit according to an alternate embodiment of the invention. [0017]
FIG. 10A is a top exploded view of the second embodiment of the fiber-optic module according to the invention. [0018]
FIG. 10B is a bottom exploded view of the second embodiment of the fiber-optic module according to the invention. [0019]
FIG. 11A is a side view of the second embodiment of the fiber-optic module of FIG. 10 mounted within a host system. [0020]
FIG. 11B is a side view of the first embodiment of the fiber-optic module of FIG. 6 mounted within a host system. [0021]
FIG. 12A is a front view of the second embodiment of the fiber-optic module of FIG. 10 mounted within a host system. [0022]
FIG. 12B is a front view of the first embodiment of the fiber-optic module of FIG. 6 mounted within a host system. [0023]
FIG. 13 is a perspective view of a host system incorporating embodiments of the fiber-optic modules of the invention. [0024]
FIG. 14 illustrates a starting sheet of material for the embodiments of the housing/shielding unit. [0025]
FIG. 15A illustrates an unfolded flat pattern layout for an embodiment of the housing/shielding unit. [0026]
FIG. 15B illustrates fold and bend lines on the unfolded flat pattern layout of FIG. 15A. [0027]
FIG. 15C illustrates an unfolded flat pattern layout for an embodiment of the housing/shielding unit. [0028]
FIG. 15D illustrates fold and bend lines on the unfolded flat pattern layout of FIG. 15C. [0029]
FIG. 16A illustrates an unfolded flat pattern layout for an embodiment of the housing/shielding unit. [0030]
FIG. 16B illustrates fold and bend lines on the unfolded flat pattern layout of FIG. 16A. [0031]
FIGS. [0032] 17A-17C illustrate alternate methods of assembling a housing/shielding unit with a module chassis frame to form a fiber-optic module.
FIG. 18A is a top plan view of a first embodiment of our new design for a one-piece shielded housing; [0033]
FIG. 18B is a right side elevational view thereof, the left side elevational view being a mirror image; [0034]
FIG. 18C is a front elevational view thereof; [0035]
FIG. 18D is a rear elevational view thereof; [0036]
FIG. 18E is a bottom plan view thereof; [0037]
FIG. 18F is a top perspective view thereof; [0038]
FIG. 18G is a bottom perspective view thereof; [0039]
FIG. 19A is a top plan view of a second embodiment of our new design for a one-piece shielded housing; [0040]
FIG. 19B is a right side elevational view thereof, the left side elevational view being a mirror image; [0041]
FIG. 19C is a front elevational view thereof; [0042]
FIG. 19D is a rear elevational view thereof; [0043]
FIG. 19E is a bottom plan view thereof; [0044]
FIG. 19F is a top perspective view thereof; [0045]
FIG. 19G is a bottom perspective view thereof; [0046]
FIG. 20A is a top plan view of a third embodiment of our new design for a one-piece shielded housing; [0047]
FIG. 20B is a right side elevational view thereof, the left side elevational view being a mirror image; [0048]
FIG. 20C is a front elevational view thereof; [0049]
FIG. 20D is a rear elevational view thereof; [0050]
FIG. 20E is a bottom plan view thereof; [0051]
FIG. 20F is a top perspective view thereof; and [0052]
FIG. 20G is a bottom perspective view thereof. [0053]
FIG. 21A is a top plan view of a first embodiment of our new design of a patterned material layer for a one-piece shielded housing; [0054]
FIG. 21B is a front elevational view thereof, the rear elevational view being a mirror image; [0055]
FIG. 21C is a bottom plan view thereof; [0056]
FIG. 21D is a right side elevational view thereof, the left side elevational view being a mirror image; [0057]
FIG. 22A is a top plan view of a second embodiment of our new design of a patterned material layer for a one-piece shielded housing; [0058]
FIG. 22B is a front elevational view thereof, the rear elevational view being a mirror image; [0059]
FIG. 22C is a bottom plan view thereof; [0060]
FIG. 22D is a right side elevational view thereof, the left side elevational view being a mirror image; and [0061]
FIG. 23 is a top plan view of a third embodiment of our new design of a patterned material layer for a one-piece shielded housing, a bottom plan view being a mirror image and the patterned material layer being a thin and flat sheet so that only the top plan view need be shown. [0062]
FIG. 24 is a top perspective view of a fiber optic module for another embodiment of the invention. [0063]
FIG. 25 is a bottom perspective view of the fiber optic module of FIG. 24. [0064]
FIG. 26A is a rear perspective view of the fiber optic module of FIG. 24. [0065]
FIG. 26B is a top view of the fiber optic module of FIG. 24. [0066]
FIG. 27 is a side view of the fiber optic module of FIG. 24. [0067]
FIG. 28 is a front view of the fiber optic module of FIG. 24 mounted against a faceplate, backplate, or bezel in a system. [0068]
FIG. 29 is a side view of the fiber optic module of FIG. 24 mounted in a system. [0069]
FIG. 30 is a top view of the fiber optic module of FIG. 24 mounted in a system. [0070]
FIG. 31 is a top view of a pattern for a front portion of a shielded housing/cover of the fiber optic module of FIG. 24. [0071]
FIG. 32 is a top view of the pattern of FIG. 31 including bend/fold lines. [0072]
FIG. 33 is a top perspective view of a fiber optic module for another embodiment of the invention. [0073]
FIG. 34 is a side view of the fiber optic module of FIG. 33. [0074]
FIG. 35 is a top view of the fiber optic module of FIG. 33. [0075]
FIG. 36 is a front view of the fiber optic module of FIG. 33. [0076]
FIG. 37 is a side view of the fiber optic module of FIG. 33 mounted in a system. [0077]
FIG. 38 is a top view of the fiber optic module of FIG. 33 mounted in a system. [0078]
FIG. 39 is a top view of a pattern for a front portion of a shielded housing/cover of the fiber optic module of FIG. 33. [0079]
FIG. 40 is a top view of the pattern of FIG. 39 including bend/fold lines.[0080]
Like reference numbers and designations in the drawings indicate like elements providing similar functionality. [0081]

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description of the invention, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be obvious to one skilled in the art that the invention may be practiced without these specific details. In other instances well known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the invention. [0082]
The invention includes embodiments of fiber-optic modules and their methods of manufacture and assembly of component parts. Fiber-optic module generally refers to fiber-optic transmitter modules, fiber-optic receiver modules, and fiber-optic transceiver modules. The various fiber-optic modules can also be referred to as opto-electronic transmitter, receiver or transceiver modules; and electro-optic transmitter, receiver or transceiver modules. The fiber-optic module of the invention is capable of reducing electromagnetic interference (EMI) from both the fiber-optic module and from the system that incorporates the fiber-optic module. In accordance with one embodiment of the invention, a fiber-optic module comprises a module chassis frame and a housing/shielding unit. The housing/shielding unit can be formed of one piece in which case it can also be referred to as a one-piece integrated housing/shielding unit, a one piece shielded housing, an EMI box or container, or a single-piece shielded housing integrating a protection function and a shielding function. The module chassis frame can also be referred to as a chassis, a frame, or a support fixture. The housing/shielding unit functions both as a protective outer housing for the fiber-optic module as well as an EMI suppression device and a chassis grounding feature. The housing/shielding unit can protect and shield the optical, electrical, and optical-electrical components within a fiber-optic module. The housing/shielding unit can be formed out of conductive materials such as a metal, a plated plastic, a conductive plastic or other electrically conductive material. The module chassis frame can be formed of a nonconductive material such as a non-conductive plastic. The module chassis frame can also be formed of a conductive material such as sheet metal, a plated plastic, or conductive plastic so as to provide, EMI shielding as well. The module chassis frame is the central structural support to which components of the fiber-optic module attach. These components can include an opto-electronic transmitter and/or an opto-electronic receiver. In the case of a fiber-optic transceiver module, the fiber-optic module includes a transmitter optical subassembly, a receiver optical subassembly and an electrical subassembly. Each of the opto-electronic transmitter and the opto-electronic receiver has a header which is shielded by a hollow cylindrical shielding collar. The hollow cylindrical shielding collar provides electromagnetic shielding as well. The opto-electronic transmitter may include a Vertical Cavity Surface Emitting Laser (VCSEL) or a conventional semiconductor laser mounted inside of the header. [0083]
The housing/shielding is a multi-sided conductive enclosure than can be formed out of sheet metal, plated plastic, conductive plastic or other electrically conductive material. In one embodiment, sheet metal is etched or stamped to form the housing/shielding unit. The housing/shielding unit also includes a pair of flaps and a septum which allow it to be spot-welded, soldered, glued or otherwise fastened after it is attached to the module chassis frame. The housing/shielding unit forms an enclosure that surrounds the module chassis frame. Fingers or tabs extend from the housing/shielding unit to ground it to a bezel, a faceplate, backplate, or a wall of a housing of a host system. In one embodiment, the fingers press against the bezel, backplate, faceplate or wall of the housing of the host system to seal electromagnetic radiation therein. In another embodiment, the fingers press against an opening in the bezel, the faceplate, backplate, or the wall of the housing of the host system to seal electromagnetic radiation therein. [0084]
The grounding scheme for the fiber-optic module includes signal grounding and chassis grounding. Two grounds are utilized for isolation to prevent currents induced in the chassis ground from affecting the integrity of signal ground. Signal ground is provided through one or more ground pins of a transceiver printed circuit board (PCB) next to the signal pins. The one or more ground pins couple to ground traces on a printed circuit board of the host system. Chassis ground is established by coupling to an outer housing of the host system which is electrically isolated from the signal ground. [0085]
The invention employs a housing/shielding unit that functions both as protective outer housing as well as an EMI shield or suppression device. The housing/shielding unit is a multi-sided enclosure which can be made from one piece or a single piece of sheet metal, plated plastic or other electrically conductive material having an opening at one end for receiving a fiber-optic connector to couple to one or more fiberoptic cables. [0086]
Referring now to FIG. 1, an fiber-[0087] optic module 100 of the invention is illustrated. In one embodiment, the fiber-optic module 100 is a 1×9 fiber-optic transceiver module. In which case the fiber-optic module is a duplex-SC transceiver designed for use in Gigabit Ethernet applications and is compliant with specifications for IEEE-802.3z Gigabit Ethernet (1000Base-SX) and Class 1 Laser Safety regulations, operates with 50/125 micrometer and 62.5/125 micrometer multimode optical fibers, has an Industry Standard 1×9 Footprint with integral duplex SC connector and meets a mezzanine height standard of 9.8 mm.
The fiber-[0088] optic module 100 includes a one-piece or single-piece integrated housing/shielding unit 115 and a module chassis frame 120. The fiber-optic module 100 with the one-piece or single-piece integrated housing/shielding unit 115 may also be referred to as a forward shield configuration. The housing/shielding unit 115 functions both as a housing and as an EMI shield. The housing/shielding unit 115 minimizes internal electromagnetic radiation from radiating outward and interfering with other electronic circuits and devices. It also minimizes external electromagnetic radiation from radiating inward and interfering with the operation of the fiber-optic module 100. It also minimizes the system electromagnetic radiation from leaking out through an opening in a bezel, a faceplate, backplate,, of a host panel through which the fiber-optic module is installed. The module chassis frame 120 may be formed of a conductive material, such as a conductive plastic, to provide EMI shielding and to support other components assembled thereto.
The housing/[0089] shielding unit 115 has a top side 116, a left side 117, a right side 118, and a back side 119 illustrated in FIG. 1. A pair of tangs 114A and 114B are present in the back side 119 in order to couple the back side 119 together with the left side 117 and the right side 118 respectively. The left side 117 and the right side 118 each have a tang 114A and 114B bent into an opening of a respective flaps (not shown in FIG. 1).
The housing/[0090] shielding unit 115 has one or more fingers 112 located near a nose 113 of the fiber-optic module 100 at the edges of a frontal opening 313. The one or more fingers can also be referred to as tabs. The one or more fingers are similarly shaped having a body and a tip which is round in one embodiment. The body of the fingers 112 are bent outward from the main surface in one embodiment. In an alternate embodiment the tips may be slightly bent from the body of the fingers. The fingers can be equally sized and equally spaced or have different sizing and difference spacing between each. Fingers 112A are located along an edge of top side 116 of the housing/shielding unit 115. Fingers 112B are located along an edge of side 117 of the housing/shielding unit 115. Fingers 112C are located along an edge of side 118 (not shown in FIG. 1) of the housing/shielding unit 115. Fingers 112D are located along an edge of side 119 (not shown in FIG. 1) of the housing/shielding unit 115. Fingers 112A, 112B, 112C and 112D are generally referred to as fingers 112. The fingers 112 have a forward curvature and are bent outwardly and slightly backwards from a frontal opening in the housing/shielding unit 115 as illustrated. The fingers 112 can be used to ground the housing/shielding unit 115 by coupling to a bezel or face-plate which is grounded. The fingers 112 are illustrated as being a plurality of fingers but can be one or more fingers on any one or all sides.
Referring now to FIG. 2, the fiber-[0091] optic module 100 includes the housing/shielding unit 115 and the module chassis frame 120. The housing/shielding unit further includes a septum (not shown in FIG. 2) and a nose strap 210. The septum and nose strap are folded back into the frontal opening of the housing/shielding unit around the module chassis frame 120. Prior to folding the septum and nose strap back into the frontal opening, the electrical, optical and electro-optical components are installed on the module chassis frame 120 which is then inserted into the housing 115 in one embodiment, or in another embodiment, the housing is folded around the module chassis frame 120. The nose strap 210 and the septum hold the module chassis frame 120 in place within the housing 115. The module chassis frame 120 includes one or more optical connector receptacles 211 with optical connector openings 212. In one embodiment, the one or more optical connector receptacles 211 are SC optical connector receptacles with the optical connector openings 212 being SC optical connector openings.
Referring now to FIG. 3, a rear view of the housing/[0092] shielding unit 115 is shown. The FIGS. 112A, 112B, 112C, and 112D are located along the edge of the frontal opening 313 of the housing/shielding unit 115 as shown. The housing/shielding unit 115 is a rectangular box made of sheet metal, plated plastic or any other electrically conductive material. Except for a single side of the housing/shielding unit 115 that is open so that the module chassis frame can be inserted into it, all other sides of the housing/shielding unit can be closed. Once the module chassis frame 120 is inserted into the housing/shielding unit 115 through the open side, it is closed to minimize electromagnetic radiation from the fiber optic module.
Referring now to FIG. 4A, a bottom view of the housing/[0093] shielding unit 115 is shown. The housing/shielding unit 115 has an open region 400 in its bottom side. One or more fingers 112C are located along the edge 419 of the housing/shielding unit 115. The fingers 112 curve outward and point more forward from surfaces of the housing/shielding unit. The fingers 112 have spring-like resilience (i.e. spring loaded or flexible) and provide a mechanical and electrical contact between the fiber-optic module and a bezel, a face-plate or a wall (not shown in FIG. 4). Thus, the fingers 112 can also be referred to as spring fingers or forward fingers. There are also a pair of flaps 402A and 402B and a septum 411 on the bottom side of the housing/shielding unit 115. The septum 411 the flaps 402A-402B and 405A-405B of the housing/shielding unit can be spot welded, soldered, glued, or otherwise fastened together. The housing/shielding unit 115 forms an enclosure that surrounds the module chassis frame 120. Fingers 112A, 112B, 112C, and 112D can ground the housing/shielding unit 115 to seal in electromagnetic radiation to avoid it affecting a host system, and to avoid the electromagnetic radiation of host system from leaking out through openings in the bezel, faceplate, or backplate.
Referring now to FIG. 4B, a bottom left side isometric view of an alternate housing/[0094] shielding unit 115′ is shown. The housing/shielding unit 115′ differs from housing/shielding unit 115 in the strap, left side, right side, bottom side and the back side. The housing/shielding unit 115′ is additionally longer so that the fingers 112 are nearer the front of the optical connector openings 212. That is back side 119 is replaced by back side 119′ with a retaining flap 429; left side flap 117 is replaced by left side flaps 117A and 117B separated by a left side slit 1511L; right side flap 118 is replaced by right side flaps 118A and 118B separated by a right side slit 1511R; bottom side flaps 402A, 402B, 405A and 405B are replaced by bottom side flaps 415A and 415B; strap 210 is replaced by strap 210′, septum 411 is replaced by septum 411′, and open region 400 is replaced by open region 400′. Otherwise, the housing/shielding unit 115′ and the housing/shielding unit 115 have similar elements and features including the one or more fingers 112A, 112D, 112C, and 112D.
The housing/[0095] shielding unit 115′ forms an enclosure that surrounds the module chassis frame 120 or 120′. Fingers 112A, 112B, 112C, and 112D can ground the housing/shielding unit 115′ to seal internal electromagnetic radiation therein to avoid it affecting a host system and keep out external electromagnetic radiation to increase noise immunity of the electronic and opto-electronic components inside. It also minimizes the electromagnetic radiation of the host system from leaking out of openings in the bezel, faceplate, or backplate.
Referring now to FIG. 5A, the housing/[0096] shielding unit 115 and an alternate module chassis frame 120′ are illustrated. The module chassis frame 120′ has a single pin opening 536 in its base 604′ through which all pins 612 may extend but otherwise is similar to the module chassis frame 120. The module chassis frame 120′ includes the optical connector receptacles 211 at one end and a left wall 602L and a right wall 602R coupled to the base 604′ at an opposite end. The walls 602l and 602R each have a slot 634L and 634R respectively on their inside surfaces. The optical connector receptacles 211 have a rectangular opening or slot 626 along the width of the module chassis frame 120′.
The housing/[0097] shielding unit 115 includes the front nose strap 210 and the septum 411. The front nose strap 210 may be a metal or a plastic band used for fastening or clamping the module chassis frame 120 to the housing/shielding unit 115. The front nose strap 210 can consists of three portions, a first extension portion 210A, a wrap portion 210B and a second extension portion 210C. The wrap portion 210B engages with the slot 638 of the module chassis frame 120 or 120′. The septum 411 can also be welded or bonded to bottom flaps of the housing/shielding unit 115 to hold the module chassis frame therein.
Referring now to FIG. 5B, the alternate housing/[0098] shielding unit 115′ and the alternate module chassis frame 120′ are illustrated. The housing/shielding unit 115′ includes the front nose strap 210′ and the septum 411′. The front nose strap 210′ may be a metal or a plastic strap used to fasten or clamp the module chassis frame 120 or 120′ to the housing/shielding unit 115′. The front nose strap 210′ is a single portion compared to the first extension portion 210A, wrap portion 210B and second extension portion 210C of the front nose strap 210. The nose strap 210′ engages with the slot 638 of the module chassis frame 120 or 120′. The septum 411′ can be welded or bonded to bottom flaps of the housing/shielding unit 115′ to hold the module chassis frame therein.
Referring now to FIG. 6, an exploded view of the fiber-[0099] optic module 100 of the invention is illustrated. The fiber-optic module 100 includes the integrated one-piece housing/shielding unit 115, the module chassis frame 120, and other optical, electrical and opto-electronic components. The module chassis frame 120 includes the optical connector receptacles 211 at one end and a left wall 602L and a right wall 602R coupled to a base 604 at an opposite end. The walls 602l and 602R each have a slot 634L and 634R respectively on their inside surfaces. The optical connector receptacles 211 have a rectangular opening or slot 626 along the width of the module chassis frame 120. The base 604 has one or more pin openings 636.
The optical, electrical and opto-electronic components of the fiber-[0100] optic module 100 are assembled into the module chassis frame 120. The components include a printed circuit board (PCB) 610, a packaged transmitter 620 for transmitting optical signals, a packaged receiver 621 for receiving optical signals, a pair of shielding collars 622A and 622B, a pair of SC connectors 650A and 650B, and a U-Plate 624. The shielding collars 622A and 622B can be formed from rolled sheet metal, a plated plastic, a conductive plastic, or other conductive material formed into a hollow cylinder.
In one embodiment, the [0101] transmitter 620 is an 850-nm VCSEL and the receiver 621 an integrated GaAs PIN-preamplifier or PIN-diode.
The printed [0102] circuit board 610 includes one or more PCB signal pins 612, edge traces 614 on each side for straddle mounting the transmitter 620 and the receiver 621, and integrated circuits 616 for processing signals between the signal pins 612 and the transmitter 620 and the receiver 621. The integrated circuits 616 may use a five volt (5v), a three volt (3v) or other common power supply voltage used in integrated circuits and host systems. The PCB signal pins 612 can include a transmit ground pin for transmitter components and a receive ground pin for receiver components. In an alternate embodiment, a single ground pin for electronic components may be provided, isolated from any shielding ground features for the fiber-optic module. The printed circuit board (PCB) 610 may have a ground plane on its top or bottom surfaces to couple to ground and further provide electromagnetic shielding.
The [0103] module chassis frame 120 includes a rectangular opening or slot 626, a pair of mounting posts 632 extending from its base 604 near left and right sides, slots 634L and 634R on inner sides of the walls 602L and 602R, one or more pin openings 636, and one or more optical connector receptacles 211 with one or more optical connector openings 212. In one embodiment, the one or more optical connector openings 212 is two and the optical connector openings are SC optical connector openings for a duplex SC optical connection. The one or more optical connector openings 212 is separated by a slot 638. The rectangular opening 626 receives the U-plate 624. The one or more pin openings 636 receives the one or more PCB signal pins 612. The slots 634L and 634R are press-fit slots and receive the sides of the printed circuit board 610. The pair of mounting posts 632 allow the transceiver to be mechanically coupled to a printed circuit board or the like. The mounting posts 632 can also be connected to chassis ground but should not be connected to signal ground.
The grounding scheme of the fiber-optic module can be divided into categories of signal grounding and chassis grounding. The separation of signal grounding from chassis grounding can keep currents induced in a chassis ground from affecting signal integrity. Signal ground is through one or more ground pins of the PCB pins [0104] 612 coupled from the PCB 610 to a ground trace in a host printed circuit board. The housing/ shielding unit 115 or 115′ is part of the chassis ground and electrically isolated from the signal ground, The housing/ shielding unit 115 or 115′ couples to chassis ground of a host system through one or more of the fingers. The one or more fingers couple to a host panel near a host panel opening through which the fiber-optic module may extend. The fingers surround the host panel opening and effectively reduce the size of the opening through which radiated electromagnetic energy may escape to seal the host panel opening through which the fiber-optic module may protrude. With the housing/ shielding unit 115 or 115′ coupled to chassis ground, it acts as a plug to block EMI radiated emissions from escaping. Additionally, the smaller the host panel opening, the greater the shielding effectiveness as the host system begins to resemble a Faraday cage.
The packaged [0105] transmitter 620 may contain a VCSEL or a conventional semiconductor laser and is mounted inside the transmitter port 623A. The packaged receiver 621 may include a PIN diode that is mounted inside the receiver port 623B. In one embodiment, the transmitter and receiver are each packaged into a TO package and may be referred to as the Tx Header and Rx Header respectively. Each of the packaged transmitter 620 and receiver 621 have one or more pins or terminals 619 which couple to the edge traces 614 on each side of the printed circuit board 610 to straddle mount them.
The [0106] SC connectors 650A and 650B include a lens 651A and 651B mounted inside ports 623A and 623B respectively. The ports can also be referred to as TO-can receptacles, TO-can holders, lens holders, etc. Semiconductor lasers and/or PINs can be mounted into metal TO-cans, which are then aligned into the ports or receptacles. The ports or receptacles have lenses between the fiber ferrules and the TO-cans. Note that lasers and photodiodes are not required to be packaged in TO-cans and can be packaged in other ways to mate with various shaped ports or receptacles. The ports and the packaging of the semiconductor lasers and/or PINs need only facilitate that light can be transmitted or received as the case may be. Each of the SC connectors 650A and 650B further includes a pair of snap lock clips 652 each having a retaining protrusion 653, ferrule barrels 654, support struts 656 in a front portion. Each of the SC connectors 650A and 650B further includes circular recesses 657 between each of the headers 623A and 623B and their respective flanges 655 in a rear portion. Each of the circular recesses 657 mates with the U-shaped openings 627 of the U-plate 624.
The transmitter package is assembled to the SC connector to form the Transmitter Optical Subassembly (Tx OSA). This Transmitter Optical Subassembly is then soldered onto the [0107] PCB 610. Prior to soldering the header assemblies 623A and 623B, the pair of shielding collars 622A and 622B are attached with solder to the rear of the ports 623A and 623B. The PCB 610 may be secured by two press-fit slots, one in each inner side of the module chassis frame 120. The U-plate 624 provides additional EMI sealing by minimizing leakage through the front of the module. The U-plate 624 also includes a flap 625 located at its top side. The U-plate 624 is electrically grounded to the housing/shielding unit 115 by the flap 625 making physical contact with the housing/shielding unit 115.
The optical, electro-optical, and the electronic components are assembled into the [0108] module chassis frame 120 or 120′ before the housing/shielding unit 115 encloses it. The transmitter 620 and the receiver 621 have their pins 619 coupled to the traces 614T and 614B of the printed circuit board 610. In one embodiment the pins 619 are straddle mounted to the printed circuit board 610 with some pins 619 coupled to the traces 614T on a top side of the PCB 610 and other pins 619 coupled to the traces 614B on a bottom side of the PCB 610. That is, one or more pins mount to one or more traces on one side of the printed circuit board and another one or more pins mount to one or more traces on an opposite side of the printed circuit board.
The [0109] shielding collars 622A and 622B are inserted over the ports 623A and 623B of the connectors 650A and 650B respectively to provide EMI shielding. The TO packaged transmitter 620 and receiver 621 are coupled into the ports 623B and 623A respectively. This forms the optical subassembly which is then attached to the electrical components that is in turn coupled into the module chassis frame 120. The front portion of the connectors 650A and 650B are inserted into openings 212 in the nose of the module chassis frame 120 so that the pairs of snap lock clips 652 of each are nearly flush. Next the U-plate 624 is inserted into opening 626 so that its U-openings 627 fit into the circular recesses 657 of each respective connector 650A and 650B. The Up-late 624 holds the subassembly of the optical and electrical components coupled into the module chassis frame 120. Additionally, the U-plate 624 can couple to the shielding collars 622A and 622B and the housing/ shielding unit 115 or 115′. The flap 625 of the U-plate 624 couples to the housing/ shielding unit 115 or 115′ when the fiber-optic module is fully assembled. This can electrically connect the collars 622A and 622B, the U-plate 624 and the housing/ shielding unit 115 or 115′ together if all are formed of conductive materials. Assuming they are electrically connected, grounding the housing/ shielding unit 115 or 115′ to chassis ground of a host system can also couple chassis ground into the U-plate 624 and the shielding collars 622A and 622B for electromagnetic shielding externally as well as internally. The TO-can headers of the receiver and transmitter are coupled to signal ground or the respective receiver ground and transmitter ground.
After the subassembly of optical and electrical components are coupled into the [0110] module chassis frame 120 or 120′, the housing/ shielding unit 115 or 115′ can then be assembled around it. Assembly of the housing/ shielding unit 115 or 115′ with the module chassis frame 120 or 120′ can be performed in different ways.
The housing/[0111] shielding unit 115 or 115′ can be formed out of a single sheet of material. It can then be folded around the module chassis frame 120 or 120′ with the affixed subassembly of optical and electrical components. Alternatively, the housing/ shielding unit 115 or 115′ can be pre-folded out of the single sheet of material but for one opening at a front or rear end. The module chassis frame 120 or 120′ with an affixed subassembly of optical and electrical components can then be inserted into the opening at the front or rear end of the housing/ shielding unit 115 or 115′.
In one embodiment, the housing/[0112] shielding unit 115 has all sides pre-folded but for the back side 119. The back side 119 is left unfolded so that the module chassis frame 120 can be inserted through a rear opening of the housing/shielding unit 115. In this case, a nose end of the module chassis frame 120 and the subassembly of optical and electrical components affixed thereto is inserted through the rear opening in the back of the housing/shielding unit 115 with its nose facing forward. After being completely inserted, the back side 119 is then folded down to have the tangs 114A and 114B bent inward to mate with window openings of flaps coupled to each side 117 and 118 to finish assembly of the housing/shielding unit 115 around the module chassis frame 120.
In another embodiment, the housing/[0113] shielding unit 115 has all sides pre-folded but for the septum 411 and strap 210. The septum 411 and strap 210 are left unfolded so that the module chassis frame 120 can be inserted through a frontal opening of the housing/shielding unit 115. The septum 411 and strap 210 are then folded around the module chassis frame 120 to form the housing/shielding unit 115. In this case, a rear end of the module chassis frame 120 and the affixed subassembly of optical and electrical components is inserted through the frontal opening of the housing/shielding unit 115 so that the rear faces rearward. After being completely inserted, the septum 411 and strap 210 are then folded down and around as illustrated in FIG. 5 to finish assembly of the housing/shielding unit 115 around the module chassis frame 120.
In yet another embodiment, all sides of the housing/[0114] shielding unit 115 are folded around the module chassis frame 120 and its affixed components. These methods of assembly are further described below with reference to FIGS. 14-17C.
After assembling the housing/[0115] shielding unit 115 around the module chassis frame 120 and its affixed components, then the septum 411 is welded, soldered, glued, or otherwise fastened to the pair of flaps 402A and 402B as shown in FIG. 4.
Referring now to FIG. 7, an perspective view of a housing/[0116] shielding unit 715 and the module chassis frame 120 for a fiber-optic module 700 are illustrated. The housing/shielding unit 715 is somewhat similar to the housing/shielding unit 115 but has slightly different dimensions, a few different features and employed in different mounting configurations. The housing/shielding unit 715 has one or more fingers 712 which are carved out of the surfaces near the perimeter 735 of an open end 739. The one or more fingers can also be referred to as tabs. The one or more fingers are similarly shaped having a body and a tip which is round in one embodiment. The body of the fingers 712 is bent from the main surface while the tips may be slightly bent from the body to horizontal with the surface. The fingers 712 have a backwards orientation, originating at the front or nose of the fiber-optic module 700. Thus, the one or more fingers 712 may also be referred to as backward fingers and the fiber-optic module 700 with the housing/shielding unit 715 may also be referred to as a fiber-optic module with a backward shield configuration.
The [0117] fingers 712 can be grouped into fingers 712A and fingers 712C located on a top 716 and a bottom 730 respectively of the housing/shielding unit 715. Fingers 712B and 712D are located along the edges of the opening of the housing/shielding unit 715. Although FIG. 7 illustrates six fingers 712A on a top side 716 and six fingers 712C on a bottom side 730, two fingers 712B on a left side 717, and two fingers 712D on a right side 718, one or more fingers 727 can provide a means of grounding the housing/shielding unit 715.
The housing/[0118] shielding unit 715 differs further from the housing/shielding unit 115 in that it has a different nose strap 710. The strap 710 and the septum 711 function similarly to the strap 210′ and the septum 411 of the housing/shielding unit 115′. Because the dimensions of the housing/shielding unit 715 are larger so that it can extend further forward through an opening, the strap 710 differs significantly from the strap 210 of the housing/shielding unit 115.
Referring now to FIG. 8A, a front view of the housing/[0119] shielding unit 715 is shown. In this embodiment, the housing/shielding unit 715 generally has the shape of an oblong box having six sides. Front side 738 has a frontal opening 739 where the module chassis frame 120 can be inserted. The front side 738 of the housing/shielding unit 715 includes the septum 710 that is welded or bonded to the flaps 910A and 910B. The nose strap 711 also located at the opening 739 is used for strapping the housing/shielding unit to the module chassis frame 120.
Referring now to FIG. 9A, a bottom isometric view of the housing/shielding unit is shown. Attached to the [0120] open end 911 is a front strap 710 shown in the folded down position. Also shown, are two bottom flaps 910A and 910B for welding or bonding to septum 711.
Referring now to FIG. 8B, a front view an alternate embodiment of the housing/[0121] shielding unit 715′ is shown. In this alternate embodiment, the housing/shielding unit 715′ generally has a similar shape to the housing/shielding unit 715. The housing/shielding unit 715′ differs from housing/shielding unit 715 in the left side, right side, bottom side and the back side. That is back side 719 is replaced by back side 719′ with a retaining flap 429; left side flap 717 is replaced by left side flaps 717A and 717B separated by a left side slit 1611L; right side flap 718 is replaced by right side flaps 718A and 718B separated by a right side slit 1611R; and bottom side flaps 910A and 910B are replaced by bottom side flaps 910A′ and 910B′. Otherwise the housing/shielding unit 715′ and the housing/shielding unit 715 have similar elements and features including the one or more fingers 712A, 712B, 712C, and 712D.
The housing/[0122] shielding unit 715′ forms an enclosure that surrounds a module chassis frame 120 or 120′. Fingers 712A, 712B, 712C, and 712D can ground the housing/shielding unit 715′ to seal in electromagnetic radiation (EMI) to minimize affecting a host system.
Referring now to FIG. 9B, a bottom isometric view of the alternate housing/[0123] shielding unit 715′ is shown. Attached to the open end 911 is a front strap 711 shown in the folded down position. Also shown, are two bottom flaps 910A′ and 910B′ for welding or bonding to septum 710.
Referring now to FIGS. 10A and 10B, a top and bottom exploded view of the fiber-[0124] optic module 700 of the invention is shown. In one embodiment, the fiber-optic module 700 is a 1×9 fiber-optic transceiver module. In which case, the fiber-optic module transceiver complies with the industry standard 1×9 footprint and meets the mezzanine height requirement of 9.8 mm.
The grounding scheme of the fiber-optic module can be divided into categories of signal grounding and chassis grounding. The separation of signal ground from chassis ground can keep currents induced in a chassis ground from affecting signal integrity. Signal ground is through one or more ground pins of the PCB pins [0125] 612 coupled from the PCB 610 to a ground trace in a host printed circuit board. The housing/ shielding unit 715 or 715′ is part of the chassis ground and electrically isolated from the signal ground. The housing/ shielding unit 715 or 715′ couples to chassis ground of a host system through one or more of the fingers 712. The one or more fingers 712 couple to a host panel near a host panel opening through which the fiber-optic module may extend. The fingers 712 contact the host panel opening and effectively reduce the size of the opening through which radiated electromagnetic energy may escape to seal the host panel opening through which the fiber-optic module may protrude. With the housing/ shielding unit 715 or 715′ coupled to chassis ground, it acts as a plug to block EMI radiated emissions from escaping. Additionally, the smaller the host panel opening, the greater the shielding effectiveness as the host system begins to resemble a Faraday cage.
The fiber-[0126] optic module 700 of the invention includes a housing/ shielding unit 715 or 715′, and a module chassis frame 120 or 120′. The optic, electronic, and opto-electronic components of the fiber-optic module are placed into the module chassis frame 120. These components and their assembly were previously described with reference to FIG. 6 and the fiber-optic module 100 and are not repeated again for brevity. When the housing/ shielding unit 715 or 715 is assembled around the module chassis frame and the optic, electronic, and opto-electronic components affixed thereto, it can couple to the flap 625 of the U-plate 624 so that it an be electrically grounded to chassis ground. Additionally, the U-plate 624 can couple to the shielding collars 622A and 622B. This can electrically connect the collars 622A and 622B, the U-plate 624 and the housing/ shielding unit 715 or 715′ together if all are formed of conductive materials. Assuming they are electrically connected, grounding the housing/ shielding unit 715 or 715′ to chassis ground of a host system can also couple chassis ground into the U-plate 624 and the shielding collars 622A and 622B for electromagnetic shielding externally as well as internally.
After all the components have been attached to the [0127] module chassis frame 120 or 120′, the housing/ shielding unit 715 or 715′ can then be assembled around it. Assembly of the housing/ shielding unit 715 or 715′ around the module chassis frame 120 can be performed in the same ways previously described for the housing/ shielding unit 115 or 115′.
Referring now to FIGS. 11A and 11B, a magnified side view and a magnified frontal view of the fiber-[0128] optic module 700 within a host system is illustrated. The fiber-optic module 700 includes a backward shield which is provided by the one-piece or single-piece integrated housing/ shielding unit 715 or 715′. The fiber-optic module 700 with the one-piece or single-piece integrated housing/ shielding unit 715 or 715′ provides an extended mount as illustrated by its nose extending beyond a bezel, faceplate, or backplate. The host system may be a hub, switch, bridge, server, personal computer, or other network or electronic equipment desiring to connect to a communication system using an fiber-optic module. The fiber-optic module 700 is coupled to a printed circuit board 1130 within the host system. A bezel, faceplate, or backplate 1110 of the host system has a transceiver opening 1112 through which the nose of the fiber-optic module extends when its coupled to the host system. The transceiver opening 1120 of the bezel 1110 is sized to appropriately mate with the fingers 712 of the fiber-optic module 700. The opening 1120 has an inner surface 1114 which mates with the fingers 712 to make an electrical coupling. By making contact to the inner surface 1114, a backside surface of the bezel 1110 can be insulated to avoid shorting an electrical component that might make contact thereto. When the nose of the fiber-optic module is inserted into the opening 1112 or the opening 1112 is threaded over the nose of the fiber-optic module 700, the fingers 712 compress towards the fiber-optic module when mating with the inner surface 1114 and expand outward to form a tight mechanical fit and a reliable electrical connection. The expansion of the fingers 712 outward effectively make the opening 1120 smaller through which radiated electromagnetic energy might otherwise escape. The fingers 712 also deter the nose of the fiber-optic module 700 from extending excessively out through the opening 1120 of the bezel 1110. With the bezel 1110 grounded by the chassis of the host system, the housing/shielding unit 715 of the fiber-optic module can be grounded by one or more fingers 712 coupling to the inner surface 1114 of the opening 1120. Alternatively, the housing/shielding unit 715 of the transceiver 700 can be grounded through a pin or other connection coupled to the PCB 1130 of the host system.
Referring now to FIGS. 12A and 12B, a magnified side view and a magnified frontal view of the fiber-[0129] optic module 100 within a host system is illustrated. The host system may be a switch, bridge, a server, personal computer, or other network or electronic equipment desiring to connect to a communication system using an fiber-optic module. The fiber-optic module 100 is coupled to a printed circuit board 1130 within the host system. A bezel, faceplate, or backplate 1210 of the host system has a transceiver opening 1220 through which the nose of the fiber-optic module partially extends when coupled to the host system. The fiber-optic module 100, a forward shield configuration with the one-piece or single-piece integrated housing/ shielding unit 115 or 115′, provides a flush mount as illustrated by FIG. 12A. The transceiver opening 1220 of the bezel 1210 is sized appropriately to allow insertion of a fiber-optic connector into the fiber-optic module 100. The bezel, faceplate, or backplate 1210 of the host system has a backside surface 1214 to which the fingers 112 can make an electrical and a mechanical coupling. Furthermore, the fingers 112 deter the EMI of both the fiber-optic module 100 and the host system board 1130 from extending excessively out through the transceiver opening 1212 of the bezel 1210. When the nose of the fiber-optic module is inserted into the opening 1112 or the opening 1112 is threaded over the nose of the fiber-optic module 100, one or more of the fingers 112 couple to the back side surface 1214 around the opening 1212 of the bezel 1210. With the bezel 1210 grounded by the chassis of the host system, the housing/shielding unit 115 of the fiber-optic module 100 can be grounded by one or more fingers 112 coupling to the back side surface 1214 of the bezel 1210. Alternatively if the bezel is coupled to a chassis ground trace, the housing/ shielding unit 115 or 115′ of the fiber-optic module 100 can be grounded through a pin or other grounding feature that is coupled to a chassis ground trace of the PCB 1130 of the host system commonly coupled to the bezel.
Referring now to FIG. 13, an [0130] exemplary host system 1300 is illustrated having the fiber-optic module 100 and the fiber-optic module 700. The host system 1300 has a bezel, a faceplate or a host panel 1310 with opening 1120 and opening 1220 for the fiber-optic module 700 and the fiber-optic module 100 respectively. The fiber-optic module 700 is coupled to host printed circuit board 1130. The fiber-optic module 100 is coupled to host printed circuit board 1130′. The host printed circuit boards 1130 and 1130′ may include a ground plane on a top surface or bottom surface under the area of the fiber optic module 100 and 700 in order to provide additional electromagnetic shielding. With openings 1120 and 1220 being relatively small encompassed by the housing/ shielding unit 715 or 715′ of the fiber-optic module 700 and the housing/ shielding unit 115 or 115′ of the fiber-optic module 100 respectively, the host system 1300 begins to resemble a Faraday cage. The housing/ shielding unit 115, 115′, 715, 715′ effectively seals openings 1120 and 1220 in the host panel 1310 to deter electromagnetic radiation from leaking into or out of the host system. The one or more fingers 112 of the housing/ shielding unit 115 or 115′ can surround the opening 1220. The one or more fingers 112 of the housing/ shielding unit 115 or 115′ can expand into the opening 1120. With the housing/ shielding unit 115 or 115′ coupled to chassis ground, it acts as a plug to block EMI radiated emissions from escaping.
Most equipment such as the [0131] host system 1300 utilizing high-speed fiber-optic modules are required to meet the requirements of: 1) the FCC in the United States; 2) the CENELEC EN55022 (CISPR 22) specification in Europe; and 3) the VCCI in Japan. The fiber- optic modules 100 and 700 are designed to perform to these specified limits of EMI including complying with FCC Class B limits. The fiber- optic modules 100 and 700 are also designed to provide good noise immunity from externally generated radio-frequency electromagnetic fields. Key components in the fiber- optic modules 100 and 700 to achieve good electromagnetic compliance (EMC) for EMI and external noise immunity are the internal shields 622A and 622B, a metal or conductive plastic module chassis frame 120 or 120′, and the housing/ shielding unit 115, 115′, 715 or 715′ with fingers 112 or 712 respectively of the fiber- optic modules 100 and 700.
The fiber-[0132] optic modules 100 and 700 are further designed to meet Class 1 eye safety and comply with FDA 21CFR1040.10 and 1040.11 and the IEC 825-1.
Referring now to FIGS. [0133] 14-17C, methods of forming the housing/shielding units 115′ and 715′ out of a sheet of a material layer and assembly with the module chassis frame 120 or 120′ is illustrated.
In FIG. 14, a starting sheet of a layer of [0134] material 1400 for the housing/shielding units 115, 115′, 715 and 715′ is illustrated. The sheet of material 1400 is a conductive material and can be a metal, a plated plastic, a conductive plastic or other known type of electrically conductive material. A first step in the process is to stamp, etch or cut the patterns for the housing/ shielding unit 115, 115′, 715 or 715′ out of the sheet of material 1400.
Referring now to FIG. 15A, an unfolded [0135] flat pattern layout 1500 for the housing/shielding unit 115′ is illustrated. The unfolded flat pattern layout 1500 is a patterned material layer for the housing/shielding unit 115′ formed out of the starting sheet of the layer of material 1400. In the unfolded flat pattern layout 1500, the forward fingers 112, tangs 114A and 114B, strap 210 and the septum 411′ of the housing/shielding unit 115′ are easily discernable. A pair of left and right window openings 1522L and 1522R are also visible in the unfolded flat pattern layout 1500.
Referring now to FIG. 15B, fold/bend lines are illustrated on the unfolded [0136] flat pattern layout 1500 to form the housing/shielding unit 115′. A slightly alternate pattern and alternate fold/bend lines can be utilized to form the housing/shielding unit 115. The fold/bend lines illustrated on the unfolded flat pattern layout 1500 make other features and components of the housing/shielding unit 115′ discernable. The fold/bend lines illustrated in FIG. 15B include left flap and right flap fold lines 1502L and 1502R, a back flap fold line 1504, left and right tang fold lines 1505L and 1505R, a retaining flap fold line 1506, left wing and right wing fold lines 1508L and 1508R, finger base bend line 1512, left bottom flap and right bottom flap fold lines 1514L and 1514R, a strap fold line 1516, and a septum fold line 1517.
A [0137] left wing 1520L and a right wing 1520R include tang window openings 1522L and 1522R respectively. The tangs 114A and 114B mate with the tang window openings 1522L and 1522R respectively to hold the left wing and right wing coupled to the back side 119′ after folding. The septum 411′ is coupled to the right bottom flap 415A and the left bottom flap 415B with an adhesive or a weld to hold the housing/shielding unit and the module chassis frame assembled together.
The left [0138] wing fold line 1508L defines the left wing 1520L from the left side flap 117B. The right wing fold line 1508R defines the right wing 1520R from the right side flap 118B. The right side fold line 1502R and the right side slit 1511R defines right flaps 118A and 118B from the top side 116. The left side fold line 1502L and the left side slit 1511L defines left flaps 117A and 117B from the top side 116. The right bottom flap fold line 1514R defines the right bottom flap 415A. The left bottom flap fold line 1514L defines the left bottom flap 415B. The retaining flap fold line 1506 defines a retaining flap 429 coupled to the back side flap 119′.
The fold/bend lines illustrated on the unfolded [0139] flat pattern layout 1500 are folded and/or bent to form the housing/shielding unit 115′ as illustrated in FIG. 4B. Generally, the folds along fold lines are made at nearly a ninety degree angle but for the fold lines of the tangs 114A and 114B and fingers. The fingers 112 may be first bent or lastly bent to curve outward along the bend lines 1512. The left flaps 117A and 117B and the right flaps 118A and 118B may be the next to be folded or they may be the first to be folded along fold lines 1502L and 1502R. The right bottom flap 415A and the left bottom flap 415B are next folded along the right bottom flap fold line 1514R and the left bottom flap fold line 1514L respectively. The next sequence of fold/bend steps can depend upon the method of assembly of the fiber-optic module utilized.
In a first case, the front of the housing/[0140] shielding unit 115′ is assembled first. In this case, the septum 411′ is folded along fold line 1517 and then the strap 210′ is folded along fold line 1516. This is followed by the left wing 1520L and the right wing 1520R being folded along the left wing fold line 1508L and the right wing fold line 1508R respectively; the back side flap 119′ being folded along the fold line 1504; the tangs 114A and 114B being folded along fold lines 1505L and 1505R respectively; and the retaining flap 429 being folded along the retaining flap fold line 1506.
In a second case, the rear of the housing/[0141] shielding unit 115′ is assembled first. In this case, the left wing 1520L and the right wing 1520R are folded along the left wing fold line 1508L and the right wing fold line 1508R respectively; the back side flap 119′ is folded along the fold line 1504; the tangs 114A and 114B are folded along fold lines 1505L and 1505R respectively; and the retaining flap 429 is folded along the retaining flap fold line 1506. This is followed by the septum 411′ being folded along fold line 1517 and then the strap 210′ folded along fold line 1516.
In yet another case for assembly of the fiber-optic module, either order of assembly in the first or second case can be utilized or mixed together. The one or [0142] more fingers 112 may alternately be bent outward from a frontal opening the into their curved shape as a last step in the folding/bending process.
A slightly alternate pattern of the [0143] layout 1500 with alternate fold/bend lines is utilized to fold and bend into shape to form the housing/shielding unit 115 as illustrated in FIGS. 1-3, 4A, 5 and 12A.
Referring now to FIG. 15C, an unfolded [0144] flat pattern layout 1500′ for the housing/shielding unit 115 is illustrated. The unfolded flat pattern layout 1500 is a patterned material layer for the housing/shielding unit 115 formed out of the starting sheet of the layer of material 1400. In the unfolded flat pattern layout 1500′, the forward fingers 112, tangs 114A and 114B, strap 210 and a septum 411 of the housing/shielding unit 115 are easily discernable. The pair of left and right window openings 1522L and 1522R are also visible in the unfolded flat pattern layout 1500′.
Referring now to FIG. 15D, fold/bend lines are illustrated on the unfolded [0145] flat pattern layout 1500′ to form the housing/shielding unit 115. The fold/bend lines illustrated on the unfolded flat pattern layout 1500′ make other features and components of the housing/shielding unit 115 discernable. The fold/bend lines illustrated in FIG. 15D include left flap and right flap fold lines 1502L′ and 1502R′, a back flap fold line 1504, left and right tang fold lines 1505L and 1505R, left wing and right wing fold lines 1508L and 1508R, finger base bend line 1512, left bottom flap and right bottom flap fold lines 1514L′ and 1514R′, a first strap fold line 1516′, and a second strap fold line 1517′.
The fold bend lines of the unfolded [0146] flat pattern layout 1500′ are similar to the fold/bend lines of the unfolded flat pattern layout 1500 but for left flap and right flap fold lines 1502L′ and 1502R′, left bottom flap and right bottom flap fold lines 1514L′ and 1514R′, a first strap fold line 1516′, and a second strap fold line 1517′.
The right [0147] side fold line 1502R′ defines the right flap 118 from the top side 116. The left side fold line 1502L′ defines left flap 117 from the top side 116. The right bottom flap fold line 1514R′ defines the right bottom flaps 402A and 405A. The left bottom flap fold line 1514L′ defines the left bottom flaps 402B and 405B. The back fold line 1504 defines the back side flap 119 from the top side 116.
The first [0148] strap fold line 1516′ and the second strap fold line 1517′ define the first extension portion 210A, the wrap portion 210B and the second extension portion 210C of the strap 210. The strap 210 is folded along the first strap fold line 1516′ and the second strap fold line 1517′. The septum 411 can couple to the right bottom flaps 402A and 405A and the left bottom flaps 402B and 405B with an adhesive or a weld to hold the housing/shielding unit and the module chassis frame assembled together.
The fold/bend lines illustrated on the unfolded [0149] flat pattern layout 1500′ are folded and/or bent to form the housing/shielding unit 115 as illustrated in FIGS. 1, 2, 3, and 4A. Generally, the folds along fold lines are made at nearly a ninety degree angle but for the fold lines of the tangs 114A and 114B and fingers 112. The fingers 112 may be first bent or lastly bent to curve outward along the bend lines 1512. The left flap 117 and the right flap 118 may be the next to be folded or they may be the first to be folded along fold lines 1502L′ and 1502R′. The right bottom flaps 402A and 405A and the left bottom flaps 402B and 405B are next folded along the right bottom flap fold line 1514R′ and the left bottom flap fold line 1514L′ respectively. The next sequence of fold/bend steps can depend upon the method of assembly of the fiber-optic module utilized. These were previously described with reference to the unfolded flat pattern layout 1500 of FIG. 15B.
Referring now to FIG. 16A, the unfolded [0150] flat pattern layout 1600 for the housing/shielding unit 715′ is illustrated. The unfolded flat pattern layout 1600 is a patterned material layer for the housing/shielding unit 715′ formed out of the starting sheet of the layer of material 1400. In the unfolded flat pattern layout 1600, the backward fingers 712, tangs 114A and 114B, strap 710 and the septum 711 of the housing/shielding unit 715′ are easily discernable. A pair of left and right window openings 1622L and 1622R are also visible in the unfolded flat pattern layout 1600.
Referring now to FIG. 16B, fold/bend lines are illustrated on the unfolded [0151] flat pattern layout 1600 to form the housing/shielding unit 715′. A slightly alternate pattern and alternate fold/bend lines can be utilized to form the housing/shielding unit 715. The fold/bend lines illustrated on the unfolded flat pattern layout 1600 make other features of the housing/shielding unit 715′ discernable.
The fold/bend lines illustrated in FIG. 16B include left flap and right [0152] flap fold lines 1602L and 1602R, back flap fold line 1604, left and right tang fold lines 1605L and 1605R, retaining flap fold line 1606, left wing and right wing fold lines 1608L and 1608R, finger base bend line 1612B, finger tip bend line 1612T, left bottom flap and right bottom flap fold lines 1614L and 1614R, strap fold line 1616, septum fold line 1617. Generally, the folds along fold lines are made at nearly a ninety degree angle but for the fold lines of the tangs 114A and 114B and fingers.
A [0153] left wing 1620L and a right wing 1620R include window openings 1622L and 1622R respectively. The tangs 114A and 114B mate with the window openings 1622L and 1622R respectively to hold the left wing and right wing coupled to the back side 719′ after folding.
The left [0154] wing fold line 1608L defines the left wing 1620L from the left side flap 717B. The right wing fold line 1608R defines the right wing 1620R from the right side flap 718B. The right side fold line 1602R and the right side slit 1611R defines right flaps 718A and 718B from the top side 716. The left side fold line 1602L and the left side slit 1611L defines left flaps 717A and 717B from the top side 716. The right bottom flap fold line 1614R defines the right bottom flap 910A′. The left bottom flap fold line 1614L defines the left bottom flap 910B′. The retaining flap fold line 1606 defines a retaining flap 1626 coupled to the back side flap 719′.
The fold/bend lines illustrated on the unfolded [0155] flat pattern layout 1600 are respectively folded and/or bent to form the housing/shielding unit 715′ as illustrated in FIGS. 8B and 9B. The sequence of folding and bending of the fold lines in the unfolded flat pattern layout 1600 is similar to that of the unfolded flat pattern layout 1500 but for the fingers. The fingers 712 for the housing/shielding unit 715′ or 715 are generally easier to push or pull out of the surface of the unfolded flat pattern layout 1600 first. Then, the sequence of folding and bending can proceed similarly for any of the three methods of assembly previously described.
Referring now to FIGS. [0156] 17A-17C, methods of assembly of the housing/shielding units 115 and 715 with the module chassis frame 120 is illustrated.
In FIG. 17A, the [0157] layout 1500 or 1600 are placed on top of the module chassis frame 120. Folding and bending is then performed around the module chassis frame 120 or 120′ along the fold lines and bend lines described in FIGS. 15A-15B or 16A-16B respectively to form the housing/ shielding unit 115, 115′, 715 or 715′. The housing/ shielding unit 115, 115′, 715 or 715′ then surrounds the module chassis frame 120 or 120′. The tangs 114A and 114B are then folded into the window openings 1522L and 1522R or 1622L and 1622R. This results in a substantially complete fiber-optic module such as fiber-optic module 100 illustrated in FIG. 1 for example.
In FIG. 17B, the [0158] layout 1500 or 1600 is first folded and bent along the fold lines and bend lines described in FIGS. 15A-15B or 16A-16B respectively but for fold lines 1516 and 1517 or 1616 and 1617. This leaves the front of the housing/ shielding unit 115, 115′, 715 or 715′ open without the strap 710 and the septum 711 being folded. The module chassis frame 120 or 120′ with the affixed components is inserted into the frontal opening with its rear entering first. Then the strap 210, 210′ or 710 and the septum 411 or 711 are then folded fold lines 1516 and 1517 or 1616 and 1617 as described in FIGS. 15A-15B and FIGS. 16A-16B to hold the module chassis frame 120 or 120′ within the housing/ shielding unit 115, 115′, 715 or 715′. After being folded, the septum 411 or 711 is affixed in place by being welded by spot welding, soldered with a solder, glued with an adhesive or otherwise fastened to a pair of bottom flaps. This results in a substantially complete fiber-optic module such as fiber-optic module 100 illustrated in FIG. 1 for example.
In FIG. 17C, the [0159] layout 1500 or 1600 is first folded and bent along the fold lines and bend lines described in FIGS. 15A-15B or 16A-16B respectively but for fold lines 1504, 1505L, 1505R, 1506, 1508L and 1508R or 1604, 1605L, 1605R, 1606, 1608L and 1608R. After being folded, the septum 411 or 711 is affixed in place by glue or welding. This leaves the rear of the housing/ shielding unit 115, 115′, 715 or 715′ open without the back side flap 119′ or 719′ and the left and right wings 1520L or 1620L and 1520L or 1620R being folded. The front end of the module chassis frame 120 or 120′ with the affixed components is inserted into the rear opening of the housing/shielding unit, nose first. The left and right wings 1620L and 1620R are then folded followed by back side flap 119′ or 719′ along fold lines 1504, 1506, 1508L and 1508R or 1604, 1606, 1608L and 1608R as shown and described in FIGS. 15A-15B or 16A-16B respectively. The tangs 114A and 114B are then folded along fold lines 1505L and 1505R or 1605L and 1605R into the openings 1522L and 1522R or 1622L and 1622R respectively. With the back side flap 119′ or 719′ held in place, the housing/ shielding unit 115, 115′, 715 or 715′ is held around the module chassis frame 120 or 120′. This results in a substantially complete fiber-optic module such as fiber-optic module 100 illustrated in FIG. 1 for example.
Fingers of a housing/shielding unit can deter electromagnetic radiation from leaking out of the opening by expanding and/or surrounding one or more portions of the opening or expanding into host tabs as will be illustrated below. In either case the fingers of the housing/shielding unit can make a connection to ground for the shielded housing/cover. [0160]
Referring now to FIG. 24, a [0161] fiber optic module 2400 is illustrated for another embodiment of the invention. Fiber optic module 2400 includes a shielded housing/cover 2415 as well as other elements previously described in reference to fiber optic modules 100, 100′, 700 or 700′. The shielded housing/cover 2415 maybe an integrated one-piece housing/cover or a two-piece housing/cover. In the case of a two-piece housing/cover the shielded housing/cover includes a front-shielded housing/cover 2415A and rear shielded housing/cover 2415B. The rear shielded housing/cover 2415B overlaps a portion of the front-shielded housing/cover 2415A. Alternatively, the front shielded housing/cover 2415A could overlap a portion of the rear housing/cover 2415B. The fiber optic module 2400 provides forward fingers on the perimeter of the top and bottom of the nose and backward fingers in the sides near the nose and the perimeter of the shielded housing 2415. Shielded housing/cover 2415 includes forward fingers 112A′ on the top side near the perimeter, forward fingers 112C′ on the bottom side near the perimeter, backward fingers 712B′ in the left side, and backward fingers 712D′ in the right side near the perimeter. The shielded housing 2415 includes a front top side 2416A, a rear top side 2416B, a front left side 2417A, a rear left side 2417B, a backside 2419, a front right side 2418A, and a rear right side 2418B. The shielded housing/cover 2415 also includes a strap 210′ and a septum 411′.
Referring now to FIG. 25, a bottom perspective view of the [0162] fiber optic module 2400 is illustrated. Fiber optic module 2400 includes the chassis/ base 120 or 120′. The chassis or base 120 or 120′ includes vent openings 633 on the bottom side thereof. The left side 2417B of the shielded housing/cover 2415 meets the backside 2419 of the shielded housing/cover 2415 at a corner which may use a tongue and groove coupling 2430. The rear portion 2415B of the shielded housing/cover 2415 can include a back edge wrap 2429B, a left edge wrap 2429L and a right edge wrap 2429R. When assembled with chassis/ base 120 or 120′, one or more of the edge wraps can wrap around chassis/ base 120 or 120′ to couple them together. The front portion of the shielded housing/cover 2415A includes a right side bottom flap 415A and a left side bottom flap 415B. When assembled with chassis/ base 120 or 120′ the right side bottom flap 415A and the left side bottom flap 415B of the shielded housing/cover can be formed around chassis/ base 120 or 120′ to couple them together. To hold the strap 210′ in place around the chassis/ base 120 or 120′, the septum 411′ can be overlapped by the left and right side bottom flap 415A and 415B.
The [0163] forward fingers 112A′ and 112C′ and the backward fingers 712B′ and 712D′ can be formed out of different shapes including round fingertips, rectangular fingertips, or triangular fingertips. The fingers maybe arched shaped or curved or bent in one or more places, in order to provide spring pressure and expand outward to seal around an opening in an enclosure, faceplate, or bezel for input/output connections. As previously mentioned the shielded housing/cover 2415 can be an integrated one piece or a two-piece design. Similarly the shielded housing 115, 115′, 715 and 715′ can be either an integrated one-piece or a two-piece shielding housing/cover having a front portion and a rear portion. In this manner, the same rear portion 2415B of the shielded housing/cover maybe used interchangeably with different front portions, such as the front portion 2415A of the shielded housing/cover 2415. That is, by simply changing the front portion of the shielded housing/cover, backward fingers maybe supplied on top, bottom, left and right sides or forward fingers maybe provided on left, right, top and bottom sides or any combination thereof. This allows flexible assembly of fiber optic modules. The decision of the type of shielding for the fiber optic module can be postponed until the subassembly of the chassis is completed and the rear portion of the shielded housing is wrapped around it. The front portion of the shielded housing/cover being interchangeable, allows flexibility in manufacturing and meeting the demands of customers.
Referring now to FIG. 26A, a rear perspective view of the [0164] fiber optic module 2400 illustrates the forward fingers 112A′ having rounded tips while the backward fingers 712B′ have more of a triangular shaped tip.
Referring now to FIG. 26B, a top view of the [0165] fiber optic module 2400 illustrate differences in the positions of the forward fingers 112A′ and 112C′ and the backward fingers 712B′ and 712D′ in the front portion 2415A of the shielded housing/cover 2415.
Referring now to FIG. 27, a side view of the [0166] fiber optic module 2400 better illustrates different possible shapes for the forward fingers. The forward fingers may be curved or bent in differing places. The front shielded housing/cover 2415A includes the forward fingers 112A′ on a top side and the forward fingers 112C′ on a bottom side. The forward fingers 112A′ are illustrated as being curved or arched shaped in FIG. 27. The forward fingers 112C′ are illustrated as being bent in two places (i.e. bent shaped) in FIG. 27 but can take on a curved or arched shape or other bent configuration in order to make contact with a back side surface of a bezel, faceplate, or backplate. The forward fingers 112A′ can take on a bent shape or other bending configuration in order to make contact to a back side surface of a bezel, faceplate, or backplate.
Referring now to FIG. 28, a front view of the [0167] fiber optic module 2400 is illustrated mounted adjacent a bezel, faceplate, or backplate 2810. The bezel, faceplate, or backplate 2810 includes an opening 2820 to allow a fiber optic plug to be inserted into the fiber optic module 2400. Duplex SC receptacles for duplex SC plugs, provided in one embodiment, can be readily seen in the front view of the fiber optic module 2400 separated by the strap 210′.
To seal around the [0168] opening 2820, the forward fingers 112A′ and 112C′ couple (i.e. press) against the backside surface of the bezel, faceplate, or backplate 2810 adjacent to the opening 2820 without coupling into the opening 2820. That is, the forward fingers 112A′ and 112C′ are not inserted into the opening 2820. The left and right side backward fingers 712B and 712B′ also do not couple into the opening 2820 nor do they couple against the backside surface of the bezel, faceplate, or backplate 2810. Rather, the backside backward fingers 712B and 712B′ couple to host tabs (not shown in FIG. 28). The host tabs can be integrated or coupled to the bezel, faceplate, or backplate 2810.
Referring now to FIG. 29, a cutaway side view of the [0169] fiber optic module 2400 inserted into a host system 2900 is illustrated. The fiber optic module 2400 couples to a host printed circuit board 1130 or 1130′. The top forward fingers 112A′ and the bottom forward fingers 112C′ couple to a backside surface 2902 of the bezel, faceplate, or backplate 2810 as illustrated in FIG. 29. The top forward fingers 112A′ and the bottom forward fingers 112C′ do not couple to an inside surface 2902 of the opening 2820. Neither do the backward fingers 712D′ couple into the opening 2820. As can be seen, the backward fingers 712D′ (as well as the backward fingers 712B′) are offset from the opening 2820 and the backside surface 2902 of the bezel, faceplate, or backplate 2810.
Referring now to FIG. 30, a topside view of the [0170] fiber optic module 2400 coupled into the host system 2900 is illustrated. As can be seen as viewed from the topside, the host system 2900 includes a left side host tab 3010B and a right side host tab 3010A. The right side backward fingers 712D′ couple to an inside surface 3014A of the host tab 3010A. The left side backward fingers 712B′ couple to an inside surface 3014B of the host tab 3010B. The host tabs 3010A and 3010B extend along the sides of the front shielded housing/cover 2415A. The overlap may provide improved EMI performance in deterring electromagnetic radiation from leaking in and out of the opening 2820. The host tabs 3010A and 3010B may additionally provide lateral support when optical plugs are pushed into and pulled out of for the fiber optic module 2400, while the printed circuit board 1130 or 1130′ provides horizontal support. The host tabs 3010A and 3010B may be coupled to the backside 2902 of the bezel, faceplate, or backplate 2810. Alternatively, the host tabs 3010A and 3010B may be integrally formed with the bezel, faceplate, or backplate 2810 and extend backward from the backside 2902. The top forward fingers 112A′ and the bottom forward fingers 112C′ do not couple to the host tabs 3010A and 3010B. Thus, the fiber optic module 2400 can have its nose flush with the faceplate 2810.
Referring now to FIG. 31, an unfolded flat pattern layout of the [0171] front portion 2415A (i.e., the front shielded housing/cover) of the shielded housing 2415 is illustrated. The rear shielded housing/cover 2415B can be envisioned by slightly modifying FIG. 16B so that the slits 1611L and 1611R cut through the top 716 to meet each other. The unfolded flat pattern layout 2415A is a patterned material layer formed out of the starting sheet of the layer of material 1400. The front shielded housing/cover 2415A and the rear shielded housing/cover 2415B can be stamped, cut or etched out of a conductive material (i.e. a metal such as stainless steel for example). As mentioned previously, the forward fingers 112A′ and 112C′ and the backward fingers 712B′ and 712D′ can be formed out of different shapes including round fingertips, rectangular fingertips or triangular fingertips.
Referring now to FIG. 32, fold/bend lines are illustrated on the unfolded flat pattern layout of the front shielded housing/[0172] cover 2415A. The fold/bend lines illustrated on the unfolded flat pattern layout make other features of the front shielded housing/cover 2415A discernable.
The fold/bend lines illustrated in FIG. 32 include left flap and right flap fold lines [0173] 3202L and 3202R, left bottom flap and right bottom flap fold lines 3214L and 3214R, the forward finger base bend line 1512, the backward finger base bend line 1612B, the finger tip bend line 1612T, the strap fold line 1616, and the septum fold line 1617. Generally, the folds along fold lines are made at nearly a ninety degree angle but for the bend lines of the fingers 112A′, 112C′, 712B′, and 712D′.
The right bottom [0174] flap fold line 3214R defines the right bottom flap 415A. The left bottom flap fold line 3214L defines the left bottom flap 415B. The right side fold line 3202R and the right bottom flap fold line 3214R define the front right side 2418A. The left side fold line 3202L and the left bottom flap fold line 3214L define the front left side 2417A. The left flap and right flap fold lines 3202L and 3202R define the front top side 2416A.
The fold/bend lines illustrated on the unfolded flat pattern layout of FIG. 32 are respectively folded and/or bent to form the front shielding/[0175] cover 2415A as illustrated in FIGS. 24-30. The sequence of folding and bending of the fold lines in the unfolded flat pattern layout of the front shielded housing/cover 2415A is similar to that of the unfolded flat pattern layouts 1500 and 1600 but for the fingers. The backward fingers 712B′ and 712D′ can be first pushed or pulled out of the surface of the unfolded flat pattern layout. Then, the sequence of folding and bending can proceed on the front shielded housing/cover 2415A.
As previously mentioned, the [0176] forward fingers 112A′ and 112C′ and the backward fingers 712B′ and 712D′ may be arched shaped or curved or bent in one or more places, in order to provide spring pressure and expand outward to seal around the opening 2820 and/or couple to the host tabs 3010A and 3010B.
Referring now to FIG. 33, a rear perspective view of a [0177] fiber optic module 3300 is illustrated for another embodiment of the invention. Fiber optic module 3300 includes a shielded housing/cover 3315 as well as other elements previously described in reference to fiber optic modules 100, 100′, 700, 700′ and 2400. The shielded housing/cover 3315 maybe an integrated one-piece housing/cover or a two-piece housing/cover. In the case of a two-piece housing/cover the shielded housing/cover includes a front-shielded housing/cover 3315A and rear shielded housing/cover 3315B. The rear shielded housing/cover 3315B overlaps a portion of the front-shielded housing/cover 3315A in one embodiment. Alternatively, the front shielded housing/cover 3315A could overlap a portion of the rear housing/cover 3315B in another embodiment. The fiber optic module 3300 provides forward fingers on the perimeter of the left and right sides of the nose and backward fingers in the top and bottom near the nose and the perimeter of the shielded housing 3315. In particular, shielded housing/cover 3315 includes backward fingers 712A′ in the top side near the perimeter, backward fingers 712C′ in the bottom side near the perimeter (not shown in FIG. 33), forward fingers 112B′ in the left side, and forward fingers 112D′ in the right side near the perimeter. The shielded housing 3315 includes a front top side 3316A, a rear top side 3316B, a front left side 3317A, a rear left side 3317D, a backside 3319, a front right side 3318A, and a rear right side 3318B. The shielded housing 3315 also includes a strap 210′ and a septum 411′ as is shown in FIG. 25 of the shielded housing 2415.
[0178] Fiber optic module 3300 includes the chassis/ base 120 or 120′ and the optical, opto-electronic, and the electronic components assembled therein. The chassis or base 120 or 120′ includes vent openings 633 on the bottom side thereof. The left side 3317B of the shielded housing/cover 3315 meets the backside 3319 of the shielded housing/cover 3315 at a corner which may use a tongue and groove coupling. The rear portion 3315B of the shielded housing/cover 3315 can include a back edge wrap, a left edge wrap and a right edge wrap. When assembled with chassis/ base 120 or 120′ one or more of the edge wraps can wrap around chassis/ base 120 or 120′ to hold them assembled together. The front portion of the shielded housing/cover 3315A includes a right side bottom flap 415A and a left side bottom flap 415B. When assembled with chassis/ base 120 or 120′ the right side bottom flap 415A and the left side bottom flap 415B of the shielded housing/cover can be found around chassis/ base 120 or 120′ to hold them together. To hold the strap 210′ in place around the chassis/ base 120 or 120′, the septum 411′ can be overlapped by the left and right side bottom flaps 415A and 415B.
The [0179] forward fingers 112B′ and 112D′ and the backward fingers 712A′ and 712C′ can be formed out of different shapes including round fingertips, rectangular fingertips or triangular fingertips. The fingers maybe arched shaped or curved or bent in one or more places, in order to provide spring pressure and expand outward to seal around an opening. The shielded housing/cover 3315 can be an integrated one piece or a two-piece design. In this manner, the same rear portion 3315B of the shielded housing/cover maybe used interchangeably with different front portions, such as the front portion 2415A of the shielded housing/cover 2415. That is, by simply changing the front portion of the shielded housing/cover backward fingers maybe supplied on top, bottom, left and right sides or forward fingers maybe provided on left, right, top and bottom sides or any combination thereof. This allows flexible assembly of fiber optic modules. The decision of the type of shielding for the fiber optic module can be postponed until the subassembly of the chassis is completed and the rear portion of the shielded housing is wrapped around it. The front portion of the shielded housing/cover being interchangeable, allows flexibility in manufacturing and meeting the demands of customers.
Referring now to FIG. 34, a side view of the [0180] fiber optic module 3300 is illustrated. The front shielded housing/cover 3315A includes the forward fingers 112B′ extending from the left side, while the forward fingers 112D′ extend from the right side. The forward fingers 112B′ can be curved or arched shaped, bent in two places, or otherwise bent in another manner (i.e. bent shaped) in order to make contact with a back side surface of a bezel, faceplate, or backplate.
Referring now to FIG. 35, a top view of the [0181] fiber optic module 3300 illustrates differences in the positions of the forward fingers 112B′ and 112D′ and the backward fingers 712A′ and 712C′ in the front portion 3315A of the shielded housing/cover 3415. The forward fingers 112B′ and 112D′ extend from the perimeter of the front portion 3315A while the backward fingers 712A′ and 712C′ are a distance away from the perimeter extending out of the surface of the front portion 3315A.
Referring now to FIG. 36, a front view of the [0182] fiber optic module 3300 and the forward fingers 112B′ and 112D′ and the backward fingers 712A′ and 712C′ is illustrated. A bezel, faceplate, or backplate couples to the forward fingers while leaving an opening to allow one or more fiber optic plugs to be inserted into the fiber optic module 3300. Duplex SC receptacles for duplex SC plugs, used in one embodiment, can be readily seen in the front view of the fiber optic module 3300 separated by the strap 210′.
Referring now to FIG. 37, a cutaway side view of the [0183] fiber optic module 3300 inserted into a host system 3700 is illustrated. The fiber optic module 3300 couples to a host printed circuit board 1130 or 1130′. The host system 3700 includes a faceplate or bezel 3710 which has an opening 3720 to allow fiber optic plugs to connect to the fiber optic module 3300. The host system 3700 includes host tabs 3730A and 3730A, separate and apart or integral with the faceplate or bezel 3710 that can be grounded to chassis ground. The backward fingers 712A′ and 712C′ are offset from the opening 3720 and a backside surface 3712 of the bezel, faceplate, or backplate 3710. The top backward fingers 712A′ of the shielded housing 3315 couple to an inside surface 3374A of the host tab 3730A. The bottom backward fingers 712C′ couple to an inside surface 3774B of the host tab 3730B.
The [0184] host tabs 3730A and 3730B extend along the top and bottom of the front shielded housing/cover 3315A. The overlap between the host tabs and the front shielded housing/cover may provide improved EMI performance in deterring electromagnetic radiation from leaking in and out of the opening 3720. The host tabs 3730A and 3730B may additionally provide horizontal support when optical plugs are pushed into and pulled out of the fiber optic module 2400 along with the printed circuit board 1130 or 1130′. The host tabs 3730A and 3730B may be coupled to a backside 3712 of the bezel, faceplate, or backplate 3710. Alternatively, the host tabs 3730A and 3730B may be integrally formed with the bezel, faceplate, or backplate 3710 and extend backward from the backside 3712. The left side forward fingers 112B′ and the right side forward fingers 112D′ do not couple to the host tabs 3730A and 3730B but the backside 3172 of the faceplate 3710.
Referring now to FIG. 38, a cutaway topside view of the [0185] fiber optic module 3300 coupled into the host system 3700 is illustrated. To seal around the opening 3720, the forward fingers 112B′ and 112D′ couple (i.e. press) against the backside surface 3712 of the bezel, faceplate, or backplate 3710 adjacent to the opening 3720 without coupling into the opening 3720. That is, the forward fingers 112B′ and 112D′ are not inserted into the opening 3720. The top and bottom backward fingers 712A′ and 712C′ also do not couple into the opening 3720 nor do they couple against the backside surface 3712 of the bezel, faceplate, or backplate 3710. Rather, the backward fingers 712A′ and 712C′ couple to the host tabs 3730A and 3730B. Nor do the backward fingers 712A′ and 712C′ and nor do the forward fingers 112B′ and 112D′, couple to an inside surface 3724 of the opening 3720. Thus, the fiber optic module 3300 can have its nose flush with the faceplate 3710.
Referring now to FIG. 39, an unfolded flat pattern layout of the [0186] front portion 3315A (i.e., the front shielded housing/cover) of the shielded housing 3315 is illustrated. The rear shielded housing/cover 3315B can be envisioned by slightly modifying FIG. 16B so that the slits 1611L and 1611R cut through the top 716 to meet each other.
The unfolded [0187] flat pattern layout 3315A is a patterned material layer formed out of the starting sheet of the layer of material 1400. The front shielded housing/cover 3315A and the rear shielded housing/cover 3315B can be stamped, cut or etched out of a conductive material (i.e. a metal such as stainless steel for example). The forward fingers 112B′ and 112D′ and the backward fingers 712A′ and 712C′ can be formed out of different shapes including round fingertips, rectangular fingertips or triangular fingertips.
Referring now to FIG. 40, fold/bend lines are illustrated on the unfolded flat pattern layout of the front shielded housing/[0188] cover 3315A. The fold/bend lines illustrated on the unfolded flat pattern layout make other features of the front shielded housing/cover 3315A discernable.
The fold/bend lines illustrated in FIG. 40 include left flap and right [0189] flap fold lines 4002L and 4002R, left bottom flap and right bottom flap fold lines 4014L and 4014R, the forward finger base bend line 1512, the backward finger base bend line 1612B, the finger tip bend line 1612T, the strap fold line 1616, and the septum fold line 1617. Generally, the folds along fold lines are made at nearly a ninety degree angle but for the bend lines of the fingers 112B′, 112D′, 712A′, and 712C′.
The right bottom [0190] flap fold line 4014R defines the right bottom flap 415A. The left bottom flap fold line 4014L defines the left bottom flap 415B. The right side fold line 4002R and the right bottom flap fold line 4014R define the front right side 3318A. The left side fold line 4002L and the left bottom flap fold line 4014L define the front left side 3317A. The left flap and right flap fold lines 4002L and 4002R define the front top side 3316A.
The fold/bend lines illustrated on the unfolded flat pattern layout of FIG. 40 are respectively folded and/or bent to form the front shielding/[0191] cover 3315A as illustrated in FIGS. 33-38. The sequence of folding and bending of the fold lines in the unfolded flat pattern layout of the front shielded housing/cover 3315A is similar to that of the unfolded flat pattern layouts 1500 and 1600 but for the fingers. The fingers 712A′ and 712C′ can be first pushed or pulled out of the surface of the unfolded flat pattern layout. Then, the sequence of folding and bending can proceed on the front shielded housing/cover 3315A.
The [0192] forward fingers 112B′ and 112D′ and the backward fingers 712A′ and 712C′ maybe arched shaped or curved or bent in one or more places, in order to provide spring pressure and expand outward to seal around the opening 3720 and/or couple to the host tabs 3730A and 3730B.
The invention has a number of advantages over the prior art which will become clear after thoroughly reading this disclosure. [0193]
The preferred embodiments of the invention are thus described. While the invention has been described in particular embodiments, the invention should not be construed as limited by such embodiments. For example, the fiber-optic modules have been described as having one or more pairs of a transmitter and a receiver for a fiber-optic transceiver module. However, the fiber-optic modules may also have one or more transmitters only or one or more receivers only for a fiber-optic transmitter module or a fiber-optic receiver module. Rather, the invention should be construed according to the claims that follow below. [0194]

Claims

What is claimed is:

1. A fiber-optic module comprising:

a module chassis frame having optical, electrical, and opto-electronic components affixed therein, the optical, electrical, and opto-electronic components to process optical and electrical signals; and

a housing/shielding unit around the module chassis frame, the housing/shielding unit having a frontal opening to accept a fiber-optic cable connector, the housing/shielding unit is conductive and has one or more forward fingers and one or more backward fingers near an edge of the frontal opening to ground the housing/shielding unit and to provide an electromagnetic interference (EMI) seal around an opening in a bezel.

2. The fiber-optic module of claim 1 wherein,

the housing/shielding unit includes a front portion and a back portion.

3. The fiber-optic module of claim 1 wherein,

the housing/shielding unit protects the optical, electrical, and opto-electronic components and shields electromagnetic radiation.

4. The fiber-optic module of claim 1 wherein,

the one or more forward fingers couple to a backside surface of the faceplate near the opening, and

the one or more backward fingers couple to one or more host tabs of the bezel.

5. The fiber-optic module of claim 1 wherein,

the one or more forward fingers curve outward and forward from the edge of the frontal opening.

6. The fiber-optic module of claim 1 wherein,

the one or more backward fingers lift up from one or more surfaces of the housing/shielding unit and extend away from the edge of the frontal opening.

7. The fiber-optic module of claim 1 wherein,

the housing/shielding unit is metal, plated plastic, or conductive plastic.

8. The fiber-optic module of claim 1 wherein,

the module chassis frame is non-conductive and includes a pin to mount the fiber optic module to a host printed circuit board.

9. The fiber-optic module of claim 1 wherein,

the optical, electrical, and opto-electronic components include a transmitter subassembly and a receiver subassembly to transceive optical signals over a duplex optical fiber ribbon and the fiber optic module is a fiber-optic transceiver module.

10. The fiber-optic module of claim 8 wherein,

the fiber optic module includes a duplex SC optical connector and the fiber-optic module is a 1×9 fiber optic module.

11. The fiber-optic module of claim 1 wherein,

at least one forward finger of the one or more forward fingers extends from a right side and a left side of the housing/shielding unit, and

at least one backward finger of the one or more backward fingers extends from a top side of the housing/shielding unit.

12. The fiber-optic module of claim 1 wherein,

at least one backward finger of the one or more backward fingers extends from a bottom side of the housing/shielding unit.

13. The fiber-optic module of claim 1 wherein,

at least one backward finger of the one or more backward fingers extends from a top side and a bottom side of the housing/shielding unit.

14. The fiber-optic module of claim 1 wherein,

at least one backward finger of the one or more backward fingers extends from a right side and a left side of the housing/shielding unit, and

at least one forward finger of the one or more forward fingers extends from a top side of the housing/shielding unit.

15. The fiber-optic module of claim 1 wherein,

at least one forward finger of the one or more forward fingers extends from a top side and a bottom side of the housing/shielding unit.

16. The fiber-optic module of claim 1 wherein,

the one or more fingers are equally sized and equally spaced around each side around a perimeter of the housing/shielding unit.

17. The fiber-optic module of claim 1, wherein

the housing/shielding unit further has

a pair of bottom side flaps, and

a strap and a septum coupled to the strap,

the strap wrapping around a part of the frontal opening and the module chassis frame, the septum to couple to the pair of bottom side flaps, the strap and the septum to hold the module chassis frame and the housing/shielding unit together.

18. The fiber-optic module of claim 1 wherein,

the housing/shielding unit is an external electromagnetic shield and the fiber-optic module further has an internal electromagnetic shield coupled to the housing/shielding unit.

19. The fiber-optic module of claim 18 wherein,

the internal electromagnetic shield is a U-plate to provide an EMI seal around an optical connector and deter electromagnetic radiation from leaking out through the frontal opening of the fiber optic module.

20. The fiber-optic module of claim 19 wherein,

the U-plate includes a flap, the flap to couple to the housing/shielding unit to ground the U-plate when the housing/shielding unit is grounded.

21. The fiber-optic module of claim 17 wherein,

the internal electromagnetic shield is a shielding collar around an opto-electronic device to shield it from electromagnetic radiation.

22. The fiber-optic module of claim 17 wherein,

the one or more forward fingers of the housing/shielding unit are spring loaded to flex into position and couple to a bezel, faceplate, or panel, and

the one or more backward fingers are spring loaded to flex into position and couple to one or more host tabs.

23. A method of forming a shielded housing for a fiber-optic module, the method comprising:

forming a flat pattern of a front portion of the shielded housing from a sheet of conductive material, the flat pattern including one or more forward fingers and one or more backward fingers;

folding the flat pattern along fold lines to form flaps and sides of the shielded housing; and

bending the flat pattern along bend lines to form the one or more forward fingers and the one or more backward fingers of the shielded housing.

24. The method of claim 23 further comprising:

providing a back portion of the shielding housing to protect components and to shield electromagnetic radiation.

25. The method of claim 23 further comprising:

prior to the folding and the bending,

placing a flat pattern of a back portion of the shielded housing onto a chassis including an opto-electronic device to process optical and electrical signals, and

folding and bending the flat pattern of the back portion around the chassis to partially assemble the chassis and the shielded housing together.

26. The method of claim 23 wherein,

the flat pattern of the front portion of the shielded housing further includes

a strap and a septum.

27. The method of claim 23 wherein,

the folding and the bending of the flat pattern forms the front portion of the shielded housing including

a top side,

a left side flap including a left wing flap, and

a right side flap including a right wing flap.

28. The method of claim 27 wherein,

a strap extends from a front edge of the top side at one end,

and a septum extends at an opposite end of the strap.

29. The method of claim 27 wherein,

the one or more forward fingers extend from a front edge of the top side and the bottom left side flap, and the bottom right side flap.

30. The method of claim 27 wherein,

the one or more forward fingers extend from a front edge of the left side flap and the right side flap,

31. The method of claim 27 wherein,

the one or more backward fingers extend backward near a front edge from a surface of the top side.

32. The method of claim 27 wherein,

the one or more backward fingers extend from a surface of the left side flap and the right side flap.

33. The method of claim 23 wherein,

the forming of the flat pattern of the front portion of the shielded housing includes

etching the sheet of conductive material.

34. The method of claim 23 wherein,

stamping the sheet of conductive material.

35. The method of claim 23 wherein,

cutting the sheet of conductive material.

36. A front portion of a shielded housing formed by the method of claim 23.

37. A method for assembling a fiber optic module comprising:

assembling optical, electrical and optical-electrical components into a chassis to form a first subassembly;

forming a back portion of a shielded housing around the first subassembly to form a second subassembly;

storing the second subassembly in inventory waiting for customer orders; and

if a customer order is received, forming a front portion of the shielded housing around the second subassembly in response thereto.

38. The method of claim 37 wherein,

the front portion of the shielding housing includes one or more forward fingers.

39. The method of claim 37 wherein,

the front portion of the shielding housing includes one or more backward fingers.

40. The method of claim 37 wherein,

the front portion of the shielding housing includes one or more forward fingers and one or more backward fingers.

41. The method of claim 40 wherein,

the forming of the front portion around the second subassembly includes

folding a left side wing and a right side wing.

42. The method of claim 41 wherein,

the forming of the front portion around the second subassembly further includes

folding a strap and a septum, the strap folded across an open end to strap the shielded housing onto the second subassembly, the septum folded into the open end to couple to a bottom side of the shielded housing.

43. The method of claim 37 wherein,

the forming of the front portion of the shielded housing around the second subassembly further includes

forming a pattern of the front portion of the shielded housing into a sheet of conductive material, the pattern including the one or more fingers near an edge,

folding the sheet of conductive material along a plurality fold lines, and

bending the one or more fingers into shape.

44. A fiber optic module formed by the method of claim 37.

45. A fiber-optic module comprising:

a chassis having a pair of optical connector receptacles at one end and a pair of walls coupled to a base at an opposite end, the pair of walls having slots on inside surfaces, the pair of optical connector receptacles having a rectangular opening along the width of the chassis, the base having one or more pin openings;

a printed circuit board coupled into the slots in the pair of walls of the chassis, the printed circuit board having one or more pins in the one or more pin openings in the base of the chassis, the printed circuit board having electrical components to process electrical signals of the one or more pins;

a pair of opto-electronic components having pins coupled to traces of the printed circuit board at an edge, the traces coupled to the one or more pins or the electrical components of the printed circuit board, the pair of opto-electronic components to process electrical and optical signals;

a pair of optical connectors each having an optical port with a lens, a flange, a snap lock clip, a ferrule barrel, and a recess between the optical port and the flange, the pair of optical ports of the pair of optical connectors coupled to the pair of opto-electronic components respectively at one end and each of the snap lock clip and the ferrule barrel inserted into the respective pair of optical connector receptacles of the chassis at an opposite end;

a plate having a pair of u-shaped openings and a flap, the plate inserted into the rectangular opening of the chassis, the u-shaped openings of the plate engaging the recess between the optical port and the flange in each pair of the optical connectors to hold the pair of opto-electronic components and the pair of optical connectors to the chassis;

a first portion of a shielded housing around the chassis to protect the pair of opto-electronic components and the electrical components; and

a second portion of the shielded housing around the chassis coupled to the plate, the second portion of the shielded housing having one or more forward fingers and one or more backward fingers to couple to a panel.

46. The fiber-optic module of claim 45 wherein,

the shielded housing to conduct electromagnetic radiation to ground.

47. The fiber-optic module of claim 45 wherein, the first portion of the shielded housing to protect the printed circuit board, its electrical components and the pair of opto-electronic devices coupled to the printed circuit board,

the second portion of the shielded housing to shield external electrical components from electromagnetic radiation generated by the pair of opto-electronic devices and the electrical components, and

the second portion of the shielded housing to shield the pair of opto-electronic devices and the electrical components from electromagnetic radiation generated by external electrical components.

48. The fiber-optic module of claim 45 further comprising:

a pair of collars around the optical ports of the pair of optical connectors, the pair of collars coupled to the plate to couple to ground, the pair of collars to shield the pair of opto-electronic devices.

49. The fiber-optic module of claim 48 wherein,

the pair of collars to shield the pair of opto-electronic devices from electromagnetic radiation generated by the other to reduce cross-talk.

50. The fiber-optic module of claim 45 wherein,

the pair of opto-electronic devices couple to the printed circuit board by coupling pins to traces on a top side and a bottom side of the printed circuit board in a straddle mounted configuration.

51. The fiber-optic module of claim 45 wherein,

the chassis is formed of a conductive material to further shield the fiber optic module.

52. The fiber-optic module of claim 51 wherein,

the chassis further has a pair of mounting pins to mount the fiber optic module to a host printed circuit board.

53. The fiber-optic module of claim 45 wherein,

the chassis further has a pair of mounting pins coupled to a bottom surface to mount the fiber optic module.

54. The fiber-optic module of claim 45 wherein,

the chassis further has a slot between the pair of optical connector receptacles.

55. The fiber-optic module of claim 54 wherein,

the front portion of the shielded housing has a strap at one end and a septum at an opposite end to hold the shielded housing around the chassis coupled, the strap engaged in the slot of the chassis between the pair of optical connector receptacles.

56. The fiber-optic module of claim 45 wherein,

the front portion of the shielded housing is an external electromagnetic shield and the plate is an internal electromagnetic shield coupled to the external electromagnetic shield.

57. The fiber-optic module of claim 45 wherein,

the pair of optical connectors are SC optical connectors and the fiber-optic module is a 1×9 fiber-optic module.

58. The fiber-optic module of claim 45 wherein,

the one or more forward fingers curve outward and forward from the edge.

59. The fiber-optic module of claim 45 wherein,

the one or more backward fingers lift up from one or more surfaces of the shielded housing and extend backward from the edge.

60. The fiber-optic module of claim 46 wherein,

the front portion of the shielded housing is metal, plated plastic, or conductive plastic.

61. The fiber-optic module of claim 46 wherein,

the one or more forward fingers are equally sized and equally spaced around a portion of the perimeter of the shielded housing.

62. A system for providing electromagnetic interference (EMI) shielding, the system comprising:

a module chassis frame having a front end and a back end, the front end being hollow to allow for optical, electrical and optical-electrical components to be attached therein, the back end having a pair of separately enclosed compartments, each compartment to house a transmitter subassembly and a receiver subassembly, the transmitter subassembly having a first shielding collar around the transmitter subassembly and the receiver subassembly having a second collar around the receiver subassembly;

a U-plate having a top portion and a bottom portion having a pair of U-shaped openings, the top portion including a flap, the U-plate coupled into a slot of the module chassis frame to hold and shield the transmitter subassembly and the receiver subassembly;

a first portion of an electromagnetic interference (EMI) shielding box around the module chassis frame; and

a second portion of an electromagnetic interference (EMI) shielding box around the module chassis frame and coupled to the U-plate, the electromagnetic interference shielding box having one or more forward fingers around its perimeter and one or more backward fingers to contact to a host system.

63. The system of claim 62 wherein,

the EMI shielding box protects components and shield components from electromagnetic radiation.

64. The system of claim 62 wherein,

the module chassis frame is formed of a plastic, a conductive plated plastic, or a metal.

65. The system of claim 62 wherein,

the EMI shielding box is glued to the module chassis frame.

66. The system of claim 62 wherein,

the EMI shielding box is welded to the module chassis frame.

67. The system of claim 62 wherein,

the one or more forward fingers and the one or more backward fingers contact a host system faceplate of the host system to minimize electromagnetic radiation leaking out of the host system.

68. The system of claim 62 wherein,

the one or more forward fingers contact a backside of the host system faceplate around an opening.

69. The system of claim 62 wherein,

the one or more backward fingers contact a surface of one or more host tabs in the host system faceplate.

70. A fiber-optic module comprising:

a means for holding optical, electrical, and opto-electronic components, the optical, electrical, and opto-electronic components to process optical and electrical signals; and

a first portion of a means for shielding and housing the means for holding; and

a second portion of a means for shielding and housing the means for holding, the second portion having a frontal opening to accept a fiber-optic cable connector, the second portion of the means for shielding and housing being conductive and including

one or more first finger means near an edge of the frontal opening, the one or more first finger means to provide an EMI seal around an opening in a host system, and

one or more second finger means near an edge of the frontal opening, the one or more second finger means to provide an EMI seal around the opening in the host system.

71. The fiber-optic module of claim 70 wherein,

the one or more first finger means are forward fingers.

72. The fiber-optic module of claim 70 wherein,

the one or more second finger means are backward fingers and contact host tabs of the host system.

73. The fiber-optic module of claim 70 wherein,

the first and second portions of the means for shielding and housing to protect components and to shield electromagnetic radiation.

74. The fiber-optic module of claim 70 wherein,

the first and second portions of the means for shielding and housing protects the optical, electrical, and opto-electronic components and shields electromagnetic radiation.

75. The fiber-optic module of claim 70 wherein,

the first and second portions of the means for shielding and housing when coupled to ground through the one or more first finger means or the one or more second finger means, conducts electromagnetic radiation thereto.

76. The fiber-optic module of claim 70 wherein,

the one or more first finger means curve outward and forward from the edge of the frontal opening.

77. The fiber-optic module of claim 70 wherein,

the one or more second means lift up from one or more surfaces of the first portion of the shielding and housing means and extend backward from the edge of the frontal opening.

78. The fiber-optic module of claim 70 wherein,

the first and second portions of the means for shielding and housing is formed out of one of metal, plated plastic, and conductive plastic.

79. The fiber-optic module of claim 70 wherein,

the optical, electrical, and opto-electronic components include a transmitter subassembly and a receiver subassembly to transceive optical signals over an optical fiber and the fiber optic module is a fiber-optic transceiver module.