CA1293232C - Systems and methods for illuminating objects for vision systems - Google Patents
Systems and methods for illuminating objects for vision systemsInfo
- Publication number
- CA1293232C CA1293232C CA000520483A CA520483A CA1293232C CA 1293232 C CA1293232 C CA 1293232C CA 000520483 A CA000520483 A CA 000520483A CA 520483 A CA520483 A CA 520483A CA 1293232 C CA1293232 C CA 1293232C
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- Canada
- Prior art keywords
- light
- ring
- axis
- reflecting surface
- concentric
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title claims description 6
- 238000005286 illumination Methods 0.000 claims abstract description 16
- 230000003287 optical effect Effects 0.000 claims description 33
- 230000033001 locomotion Effects 0.000 claims description 13
- 239000013307 optical fiber Substances 0.000 claims description 7
- 239000011295 pitch Substances 0.000 claims description 6
- 238000006073 displacement reaction Methods 0.000 claims description 5
- 239000000835 fiber Substances 0.000 claims description 4
- 230000007246 mechanism Effects 0.000 abstract description 6
- 238000004458 analytical method Methods 0.000 abstract description 3
- 230000008859 change Effects 0.000 abstract description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 101100378101 Caenorhabditis briggsae ace-4 gene Proteins 0.000 description 1
- 241000582342 Carria Species 0.000 description 1
- STECJAGHUSJQJN-USLFZFAMSA-N LSM-4015 Chemical compound C1([C@@H](CO)C(=O)OC2C[C@@H]3N([C@H](C2)[C@@H]2[C@H]3O2)C)=CC=CC=C1 STECJAGHUSJQJN-USLFZFAMSA-N 0.000 description 1
- 101100536883 Legionella pneumophila subsp. pneumophila (strain Philadelphia 1 / ATCC 33152 / DSM 7513) thi5 gene Proteins 0.000 description 1
- 241001237728 Precis Species 0.000 description 1
- 101100240664 Schizosaccharomyces pombe (strain 972 / ATCC 24843) nmt1 gene Proteins 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- PJMPHNIQZUBGLI-UHFFFAOYSA-N fentanyl Chemical compound C=1C=CC=CC=1N(C(=O)CC)C(CC1)CCN1CCC1=CC=CC=C1 PJMPHNIQZUBGLI-UHFFFAOYSA-N 0.000 description 1
- 229940020445 flector Drugs 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 239000010438 granite Substances 0.000 description 1
- 229940034195 ionsys Drugs 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000000386 microscopy Methods 0.000 description 1
- 239000002674 ointment Substances 0.000 description 1
- 230000001151 other effect Effects 0.000 description 1
- 238000003909 pattern recognition Methods 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
Abstract
Abstract of the Disclosure An illumination system, particularly suitable for use with automatic vision system, employing an image sensing device or system, illuminates an object under analysis with the cone of light that may cover 360° or only an arc segment about a part of the object under analysis. Light from a ring source is directed toward a curved parabolic surface on a light collector ring that substantially collimates the light and tans it out radially out toward a toroidal reflector surface on an encompassing ring, the relative position of which determines the angle of incidence of a cone of light formed to fall in the region of the object, so as to illuminate particular features with optimal efficiency. To change the angle of incidence while maintaining focus, a differential drive mechanism moves the parabolic collector ring and the toroidal angle generator ring in differential fashion concurrently.
Description
~2070 ~3~3;~
syslrEMs AND MElrHoDs FOR
LLuMINAlrl~G oBJEcrs FO~ vlsroN syslrEMs Background oE the Invention The rapid growth oE automatic measurement techniques for precision products, ranging from mechanical parts made to very narrow tolerances to minute VLSI ~emiconductor products, has led to the generation of a rumber of systems for automatic inspection o~ such parts and components. In these systems, an article to be checked or measured is imaged, ~enerally through a high magniEication optical system, on an electronic image pickup device, sucll as a Vidicon, CCD array, or other image-to-signal converter. The video signals can be processed, utilizing a~apted soEtware and a microprocessor or minicomputer, to analyze the image and particular uarts oE the image. Image transEormation techniques can be used to rotate, zoom and translate the ilnage, pattern recognition techniques can be employed to compare the image to a predetermined standard, Elaws can be identiied, dimensions and spacings can be measured.
These functions can b~ performed with high reliability and Ereedom from error when the image is adequately deined.
The ~ignals derived Erom scanning of the optical image, however, depend on the physical and optical characteristics of the o~ject under examination. While the eye can readily percei~e di~Eerence~s ln color and texture, and the eye Cdll ~lsO adjust Eor reflections and other effects and a human operator can make adjustments dependent on overall perceptions, processing of the image ~ignal depends essentially upon the nature of the variations in tlle signal. Preci~e location of an edge oE a given surEace, Eor example, re~luires a high signal contrast ~etween the surEace and its background.
. ~ .~.,.
~3~32 IE the diameter of an aperture is being me~sured, for ~xample, abrupt variations in signal magnitude enable the vision system to give a reading oE the dimension that is rnuch more rapid, accurate and reliable than any system requiring operator judgment. Precision components, however, are three-dimensional in character and it is often desirable to inspect or measure sQecific attributes at different levels. If a hole is tapered, for example, and the hole is concentric with a vertical axis, the taper can be determined with accuracy by taking hole diameter readings at each end, Eor which purpose uniform illumination is not optilnal. This illustrates the general problem of so iLluminatiny an object under inspection that highlights and shadows can be used to best advalltage in displaying the features and surlaces that are ~o be inspected or measured.
Tlle ViSiOIl systems o~ the class described herein are best exempliEied by the View Engineering Model 1200, a microprocessor-based system which makes non-corltact measuremellts in three dimensions of complex parts and to an accuracy oE the order of 0.00025". In this system, object illuminatioll may be provided by a light source disposed around the objective lens of the magnification sys~em f~r the camera, or coaxially through the objective. The capability Eor enhancing different characteristics at different times has been lilnited except that limited advantages have been derived by using discrétely differing light sources in particular instances.
An illumination system which can efficiently and economically provide di~ferent, controllable, illumination of an object under study is not limited to use with vision syste~s of the type generally described. It can also be employed in microscopy, microphotometry, and microphotogrdplly, where the part being examilled is vicwed under some substantial ~293Z32 magnifica~ion and image enhancement is desirable for specific purposes.
Summary_of the Inven~ion Sys~ems and me~hods ln accordance with the lnvention employ a ligh~ source providing a hollow cylindrical sheet of diverging light together wlth a pair of curved ring reflectors.
One of the reflectors collects and collimates the cylindrical sheet of light and directs it as a lateral fan to an adjacenk reflector ring having a curved surface. The angle of deflection ~rom the second reflector forms a cone whose angle of incidence varies in accordance with the relative position of the two rings. When moving the two reflecting rings toward or away from the o~ject at dlfferential rates, the cone of illuminating light continues to ~ocus at a yiven point but with a varylng included angle that changes the highlights, shadows and contrasts in the imaga through a wide range. A feature o~
the invention is that the focal point can be changed through a wide range. Furthermore, the ring light source generating the ~heet of light ls advantayeously dlvided into separate arc segments which can be illumina~ed in different combinations so as to achieve further versatility in pre~enta~ion of the image.
In accordance with a broacl aspect of the invention there is provided a system for illuminating a ~arget object with focu~ed light at varying angles o~ incidence relative to an optical a~is and comprising:
a ring light source concentric wi~h the optical axis and providing a hollow cylinder of light directed toward the object;
a first ring reflector having an outer surface of parabolic cros~ sec~ion in a path of the cylinder of light and reflecting the li~ht into an outwardly disburslng pattern;
:a293~3~
3a 73112-3 a second ring reflector havlng an inner surface of curved cro~s section disposed about the fir3t ring re~lector and concentric therewith in a path of the pattern re~lected from the ~irst rlng reflector; and means for varying the spacing o~ the first and second ring reflector from the ob~ect, including means for moving the second ring re~lector differentially relative to the fixst.
In accordance with another bxoad aspect of the invention there is provided a method o~ examining an object with a vision system having an optical axis to enhance automatic recognition of distinctive features to be measured or identified automatically comprising the step~ o~:
illuminating an ob~ect with a conical sheath of light concentric wi~h the axis of the vision system and ~ocused on a selected point relative to the object to be analyzed; and changing an angle of incidence of the conical sheath of light while maintaining ik in ~ocus at the selected point.
In accordance with another broad aspect o~ the invention there is provided an illumination system for use with a viewing system for inspecting, measuring or recording an image of an ob~ect at an optical axis, comprislng~
means providing a hollow cylindrical illuminating llght pattern concentric with the optical axis and directed toward the obj~ct;
a ~irst ring element having a curved reflecting surfaca concentric wi~h ~he op~ical axis and re~lecting the cylindrical light in a first directlon, a second ring element having a curved reflecting sur~ace in a path of the light reflected from the first curved reflecting surface and reflecting ~he light 0 into a conical illumination pat~ern; and means coupled to move the first and second ring elements alony the optical axis wlth differential motion.
lZ9~3Z3Z
3b 73112-3 In accordance with another broad aspect of the invention there i~ provlded a light system for providing light at variable angles of incidence on an object to be viewed at a focal plane along a viewing axis perpendicular to the viewing axis, comprislng:
a flrst kody in the form of a sur~ace of revolution concentric with the viewing axis and having an ou~er reflec~ing flange on a side opposite the focal plane, the reflectiny flange defining a firs~ reflectin~ sur~ace that is parabolic in 0 cross section;
means disposed about the first body and providing a circular light source concentric with and directed onto the first reflecting sur~aae, the liyht from the source diverging within a beam angle and ~he focal point of the first reflecting surface being selected to collimate llght from the source;
a second hody in khe ~orm of a sur~ace of revolution concentric with the vlewing axis and havlng an inner reflecting flange on a side facing the focal plane, the reflecting flange defining a second re~lecting surface that approximates a circular arc in cross section and reflects light inwardly toward the viewing axis;
means coupled to the first and second bodies for moving such bodies along the viawing axis in a selected displacement ratio such that the light reflected ~rom the second surface focuses at the focal plane.
In accordance with another broad aspect of the invention thare i5 provided a vision system comprising:
a stable base having a horizontal upper surface;
a stable bridge spanning ~he upper surface in an X axis 0 direction and overlying a viewing zone on the base:
platform means on ~he upper surface of ~he base for receiving an objec~ to be viewed, ~he pla~form means including ., ~
~293~232 3c 73112-3 Y axis drive means for providing horizontal movement in the Y
direction;
X axis carria~e means mounted on the bridge and including X axis drive means ~or provlding hoxlzontal movement in the X
direction, Z axis carriage means mounted on the X axis carriage means and including drive means for providing vertical movement;
electronic camera means, including magnification means, mounted on ~he Z axis carriage means and oriented along an optical axis to view the viewing zone;
illumlnator mean~ di~posed concentrically about the electronic camera means and the optical axis for providing a cone of light on the object to be viewed, the illuminator means comprlslng a pair of ring re~lectors; and illuminator dxive means mounted on the Z axis carriage means and coupled to the illuminator means for moving the ring reflector~ in a selected displacement ratlo to maintain the cone of llght in focus a~ dif~erent angles of incidence.
In a ~pecific example of a system in accordance with the invention, a vision system has an optical axis along which a camera views an object through a magni~ication system. X, Y
and Z axis poæitloning is provided between the camera and the i~-em being examlned. A ring light source comprising a cylindrical array of optical fibers, energizable ln quadrants, is disposed concentric with khe optical axis, encompassing the lenæ magnificatlon system. The optical f~bers in the ring light source generate individually diverging beams forming a hollow cylindrical sheet of light directed downwardly ~oward the ob~ect 3~3~
under examillation. The light is reElected o~f a reElecting surface of paraboLic cross section on the inner ring, substantially radially outwardly toward a curved reflecting surface on the second outer ring. The second reflecting surface S is a toroidal segment that has a circular cross section to direct the light down to a common focal point, dependent upon the region of incidence on the second reflecting surface.
difEerential drive mechanism is coupled to the Z axis carriage to move the first and second reflector rings in the sam2 direction, but at diEferent rates of mOVeltlellt, 5uch that the focal.lengtll changes along with the angle oE inci~ence, and the ocal point remains ixed 'rheinechanisln moves separately from the Eocusing oE the camera,c;o as to provide great2r versatility.
In this arrangement, di~ferential motion is preferentially lS provided by a double rack system, with the pitch oE the teeth on the racks being in a selected ratio. Drive and idler gears between opposing racks enable the two racks to be moved in the selected ratio by a single motor, and without requiring external bearings.
- Brief Description oL the Drawings A better understanding may be had by reference to the Eollowing description, taken in con~unction with the accomparlying drawillgs, in which:
Fig. 1 is a perspective view, partially broken away, oE a vision system incorporating an illumination system in accordance with the invention;
Fig. 2 is a perspective fragmentary view of a portion of the arrangement of Fig. l;
Fig. 3 is a side sectional view of a portion oE the structur~ of Fig. 2;
3Z3;~
~, Fig. 4 is a ~ragrnentary view of a ~ortion o~ a di~ferential driv~ mechanism used in the m~cllanism of Figs. 2 and 3;
Fig. 5 is an end view of the structure oE Fig. ~; and Fig, 6 is a ~impLi~Le~ dep.. ction o~ variations in the angle of inci,-lence with di~ferent positions of the reElectors in the system of Figs. 1-5.
Detailed Description o~ the Invention A vision system 10 in accordance with the invention, as seen in Figs. 1 and 2, comprises a base console 12 having a temperature stable Elat granite table 13 on which a stage 1 i.s movable in the Y direction under control of a dri~e 15, comprising a motor and lead screw is mounted to place a product 16, indical:ed only generally, to be inspected at a given position in a viewing zone. A vertically Inountecl camera 17 points down at the view.ing zone through a magniEying lens systern 18. The camera 17 i~ mounted on a Z axis support 19 that is driven in the vertical direction by a Z axis motor 20 50 that the camera can focus on particular regions and surfaces. The camera 17 and Z axis support 19 are stably mounted on an X axis carriage 22 that is mounted on a stable vibration free bridge 23 spanning the v1ewing region above the.platform 14. The carriage 22 is translated In the horizontal plane by a drive 24 comprising a motor and lead screw. Both the drives 15 and 24 as well as the Z axis drive motor 20 are controlle~ by signals from a processor 25, which is typicalLy programmed to position the pro~uct 16 at given X and Y axis,positions relative to the camera 17 and also to ~ocusona particular level at the object. ~n illumination system 30 having elements concentric with the opt.ical axis is mounted conjointly with the camera 17 and lel-s sys~em 13 on the .r Z axis support 19.
~L~93~3;~
The illumination system 30, referring now to Figs. 2-5 as well as Fig. 1, includes a remote light source 32 on the console coupled through a Elexible optical Eiber harness 3~
having many individual optical fibers to a light ring 36 that is disposed about the lower end oE the ]ens system 18 an~
concelltric with the optical axis. As seen in the sectional view oE Fig. 3, the ends o~ tne individual optical fibers 38 are fanned out from a parallel core into a cylin~rical pattern in which the Eibers are paralleL and adjacent around the cylinder.
The light emanatin~3 from the ends oE the Eibers 38 collectively generates .~ hollow cylindQr or sileatll of light directed down towar~ the l~roduct 16. ~lowever, the light Erom each fiber end diverges at an angle of about 62 in thi3 instance, this angle varying in de~endence on the precision ot the end flat. The lS remote light ~ource 32 has our separate source~ in thi~ example, each controlling light to a different(luadrallt at the illuminator 30 and each controlled by the proce~sor 25.
Below the light ring 36, a Eir~t reElector ring 42 i3 movably mounted along the optical axis and includes a first reflector surface ~4 which is parabolic in cro~s section. The focal point of the parabola is chosen relative to the angle of ~ivergence o~ light from the fibers, to provi~e substantial collimation. Because the parabolic reflector sur~ace 4~ is in the path oE the downwardly directed light cylinder, it deflects the light radially outwar~ly from th2 circumEerence of the reElector surface 4~ to form what may be called a fan of light concentric with the optical axis of the camera 17. Thus the Eirst re-Elector ring 42 acts as a light collector as well as a light path diverter because of the parabolic sur~ace. The first reflector ring is in the form ot a surface o~ revolution whose body includes a waist section Eor receiving the li~ht ring 36.
~293;232 The outwardly directed light pattern impinges on a second reflector ring 46 outside the first ring 42, and relati-vely movable with respect to it along the Z axis. The reflect-ing surface 48 of the second reflector ring 46 is o~ circular cross section, as seen in Fig. 3. A circular or spherical segment is adequate for present purposes, although a hyperbolic curve would be preferred where higher precision is needed. The position at which the substantially horizontal fan beam ~rom the first ref]ector ring 42 impinges on the curved second re-flector surface 48 determines the allgle o~ deflection downward toward a focal point, thus acting as an angle generator. The parabolic reflector sureace 44 substantially collimates the light from the optical fibers 38 t'hat ans out toward the curved surface 48.
A differential drive mechanism 50, 'best seen in Figs. 2, 3, 4 and 5, is mounted on the X axis carriage 22, and consequen-tly is independent of the Z axis position of the camera 17 and lens system 18. ~ motor 52 ~Fig. 2) independent-ly drives the mechanism 50 so as to control the position of the second ring 46. The positions of both rings 42, 46 are changed concurrently in a certain proportionality which maintains focus as well as changing the angle o~ incidence. To this end, a pair o~ rack and pinion mechanisms are mounted in side-by-side relation, with ~ second rack 54 having a given tooth pitch being coupled to the second ring 46 by an angle bracket 55 and a first rack 56 having a greater pitch being coupled to the first ring 42 by an extending arm 57. The racks 54, 56 are offset in adjacent planes within an encompassing housing 59 attached to the Z axis support 19 (Fig. 1). Parallelism is maintained by drive and idler gears coupled wlthin the housing .~,`
f ~3 Z3;~
at spaced apart regions between the racks 54, 56. The drive gears, as seen in Figs. ~ and 5, include a irst gear 62 coupled to the shaEt oE the motor 52 and engaging the second rack 54. The firs-t gear 62 drives an adjacent second gear 64 in its plane, which is clustered with a third gear 66 in the plane of the first rack 56, and meshing with -the teeth in the first rack 56. The first and third gears 62, 6G generate a differential movement determined by the ratio of the pitches of the two racks 54, 56, the gears 62, 6~ having like diameters.
Two idlers 68, 69 are arranged to engage the racks 54, 56 to maintain parallelism without bearings. With -this arrangement, the racks 54, 56 reciprocate within the housing 59 and the needed motions are effected without the necessity for bearing supports. As seen in Fig. 5, the racks 54, 56 are attached to slider rods 70 which slide within bushings 72 in the housing.
In the operation oE the system of Fig. 1, the sequence of operation for examination of a product 16 will typically commence with an operator controlling positioning of the Y a~is stage 14 and the X axis carriage 22 to view differ-ent portions of the product 16, as these sequences and posi-tions are stored in the processor memory. At each position focal planes are selected for the lens system 18 and camera 17 by positioning the Z axis support 19, and then a preferred angle of incidence is chosen Eor light ~rom the illumination system 30. As the necessary set points Eor each position are sequentially selected by the operator, the sequence is stored in memory for that product 16. As each li~e product 16 is placed on the stage 14 in position for analysis, software for the system runs through the se~uence in conventional fashion, ,~'' 3;~
- 8a - 73112-3 focusing on and illuminating each selected point or region of the part. If the taper in the hole of the product 16 is to be ~easured, let it be assumed that the upper surface is a larger diameter and the ~25~3Z3;i~
lower surface is a smaller diameter. The calnera 17 and Lens 18 are then focused on one end or the other, and th~ illumination system 30 is shi~ted to giv2 an optimum angle oE incidence for a sharp transition in light contrast between the inner diameter 5 of the hole and the surroun~ing background Then the other end of the hole can be examined in similar fashion, with the ~ocus end angle of incidenc~ changed to show the transition most clearly. ~
~s best seen in Fig. 6, the illuminating light from 10 the ends of the optical Eibers 38 in the light ring 36 provides a 360 closed sheath oE light, but the light is somewhat divergent. Con3equently, the parabolic first re~lector surface 44 collects the light and sub~tantially collimates it "lirecting it toward the second, angle generator surEace 48, Erom wllence 15 it i9 directed toward a cone to~lard a Eocal ~oint. ~s the angle oE inci~ence is changed, the two reflector rings 42, 46 are moved together, but with a varying gap between them. Thus the light Erom the Eir~st,collector surface 44 irnpingeson a different region oE the curved, angle generator surEace 48, to change the 20 angle of illcidence b~lt maintain the same focal point.
, By controlling the remote lightsource32to illuminate dlfEerent groups o~ tb~ optical Eibers 38, in quadrants around the light ring 36, the product 16 can be illurninated from diEEerent sides, as well as angles, improviny the versa-tility 25 of the system.
While there have been described and illustrated in the drawings, various Eorm3 and variations in accordance with the invention, it wiLl be appreciated tllat the invention is not limited thereto but ellcompasses all exempliEications within the 30 scop~ of the appended claims. r
syslrEMs AND MElrHoDs FOR
LLuMINAlrl~G oBJEcrs FO~ vlsroN syslrEMs Background oE the Invention The rapid growth oE automatic measurement techniques for precision products, ranging from mechanical parts made to very narrow tolerances to minute VLSI ~emiconductor products, has led to the generation of a rumber of systems for automatic inspection o~ such parts and components. In these systems, an article to be checked or measured is imaged, ~enerally through a high magniEication optical system, on an electronic image pickup device, sucll as a Vidicon, CCD array, or other image-to-signal converter. The video signals can be processed, utilizing a~apted soEtware and a microprocessor or minicomputer, to analyze the image and particular uarts oE the image. Image transEormation techniques can be used to rotate, zoom and translate the ilnage, pattern recognition techniques can be employed to compare the image to a predetermined standard, Elaws can be identiied, dimensions and spacings can be measured.
These functions can b~ performed with high reliability and Ereedom from error when the image is adequately deined.
The ~ignals derived Erom scanning of the optical image, however, depend on the physical and optical characteristics of the o~ject under examination. While the eye can readily percei~e di~Eerence~s ln color and texture, and the eye Cdll ~lsO adjust Eor reflections and other effects and a human operator can make adjustments dependent on overall perceptions, processing of the image ~ignal depends essentially upon the nature of the variations in tlle signal. Preci~e location of an edge oE a given surEace, Eor example, re~luires a high signal contrast ~etween the surEace and its background.
. ~ .~.,.
~3~32 IE the diameter of an aperture is being me~sured, for ~xample, abrupt variations in signal magnitude enable the vision system to give a reading oE the dimension that is rnuch more rapid, accurate and reliable than any system requiring operator judgment. Precision components, however, are three-dimensional in character and it is often desirable to inspect or measure sQecific attributes at different levels. If a hole is tapered, for example, and the hole is concentric with a vertical axis, the taper can be determined with accuracy by taking hole diameter readings at each end, Eor which purpose uniform illumination is not optilnal. This illustrates the general problem of so iLluminatiny an object under inspection that highlights and shadows can be used to best advalltage in displaying the features and surlaces that are ~o be inspected or measured.
Tlle ViSiOIl systems o~ the class described herein are best exempliEied by the View Engineering Model 1200, a microprocessor-based system which makes non-corltact measuremellts in three dimensions of complex parts and to an accuracy oE the order of 0.00025". In this system, object illuminatioll may be provided by a light source disposed around the objective lens of the magnification sys~em f~r the camera, or coaxially through the objective. The capability Eor enhancing different characteristics at different times has been lilnited except that limited advantages have been derived by using discrétely differing light sources in particular instances.
An illumination system which can efficiently and economically provide di~ferent, controllable, illumination of an object under study is not limited to use with vision syste~s of the type generally described. It can also be employed in microscopy, microphotometry, and microphotogrdplly, where the part being examilled is vicwed under some substantial ~293Z32 magnifica~ion and image enhancement is desirable for specific purposes.
Summary_of the Inven~ion Sys~ems and me~hods ln accordance with the lnvention employ a ligh~ source providing a hollow cylindrical sheet of diverging light together wlth a pair of curved ring reflectors.
One of the reflectors collects and collimates the cylindrical sheet of light and directs it as a lateral fan to an adjacenk reflector ring having a curved surface. The angle of deflection ~rom the second reflector forms a cone whose angle of incidence varies in accordance with the relative position of the two rings. When moving the two reflecting rings toward or away from the o~ject at dlfferential rates, the cone of illuminating light continues to ~ocus at a yiven point but with a varylng included angle that changes the highlights, shadows and contrasts in the imaga through a wide range. A feature o~
the invention is that the focal point can be changed through a wide range. Furthermore, the ring light source generating the ~heet of light ls advantayeously dlvided into separate arc segments which can be illumina~ed in different combinations so as to achieve further versatility in pre~enta~ion of the image.
In accordance with a broacl aspect of the invention there is provided a system for illuminating a ~arget object with focu~ed light at varying angles o~ incidence relative to an optical a~is and comprising:
a ring light source concentric wi~h the optical axis and providing a hollow cylinder of light directed toward the object;
a first ring reflector having an outer surface of parabolic cros~ sec~ion in a path of the cylinder of light and reflecting the li~ht into an outwardly disburslng pattern;
:a293~3~
3a 73112-3 a second ring reflector havlng an inner surface of curved cro~s section disposed about the fir3t ring re~lector and concentric therewith in a path of the pattern re~lected from the ~irst rlng reflector; and means for varying the spacing o~ the first and second ring reflector from the ob~ect, including means for moving the second ring re~lector differentially relative to the fixst.
In accordance with another bxoad aspect of the invention there is provided a method o~ examining an object with a vision system having an optical axis to enhance automatic recognition of distinctive features to be measured or identified automatically comprising the step~ o~:
illuminating an ob~ect with a conical sheath of light concentric wi~h the axis of the vision system and ~ocused on a selected point relative to the object to be analyzed; and changing an angle of incidence of the conical sheath of light while maintaining ik in ~ocus at the selected point.
In accordance with another broad aspect o~ the invention there is provided an illumination system for use with a viewing system for inspecting, measuring or recording an image of an ob~ect at an optical axis, comprislng~
means providing a hollow cylindrical illuminating llght pattern concentric with the optical axis and directed toward the obj~ct;
a ~irst ring element having a curved reflecting surfaca concentric wi~h ~he op~ical axis and re~lecting the cylindrical light in a first directlon, a second ring element having a curved reflecting sur~ace in a path of the light reflected from the first curved reflecting surface and reflecting ~he light 0 into a conical illumination pat~ern; and means coupled to move the first and second ring elements alony the optical axis wlth differential motion.
lZ9~3Z3Z
3b 73112-3 In accordance with another broad aspect of the invention there i~ provlded a light system for providing light at variable angles of incidence on an object to be viewed at a focal plane along a viewing axis perpendicular to the viewing axis, comprislng:
a flrst kody in the form of a sur~ace of revolution concentric with the viewing axis and having an ou~er reflec~ing flange on a side opposite the focal plane, the reflectiny flange defining a firs~ reflectin~ sur~ace that is parabolic in 0 cross section;
means disposed about the first body and providing a circular light source concentric with and directed onto the first reflecting sur~aae, the liyht from the source diverging within a beam angle and ~he focal point of the first reflecting surface being selected to collimate llght from the source;
a second hody in khe ~orm of a sur~ace of revolution concentric with the vlewing axis and havlng an inner reflecting flange on a side facing the focal plane, the reflecting flange defining a second re~lecting surface that approximates a circular arc in cross section and reflects light inwardly toward the viewing axis;
means coupled to the first and second bodies for moving such bodies along the viawing axis in a selected displacement ratio such that the light reflected ~rom the second surface focuses at the focal plane.
In accordance with another broad aspect of the invention thare i5 provided a vision system comprising:
a stable base having a horizontal upper surface;
a stable bridge spanning ~he upper surface in an X axis 0 direction and overlying a viewing zone on the base:
platform means on ~he upper surface of ~he base for receiving an objec~ to be viewed, ~he pla~form means including ., ~
~293~232 3c 73112-3 Y axis drive means for providing horizontal movement in the Y
direction;
X axis carria~e means mounted on the bridge and including X axis drive means ~or provlding hoxlzontal movement in the X
direction, Z axis carriage means mounted on the X axis carriage means and including drive means for providing vertical movement;
electronic camera means, including magnification means, mounted on ~he Z axis carriage means and oriented along an optical axis to view the viewing zone;
illumlnator mean~ di~posed concentrically about the electronic camera means and the optical axis for providing a cone of light on the object to be viewed, the illuminator means comprlslng a pair of ring re~lectors; and illuminator dxive means mounted on the Z axis carriage means and coupled to the illuminator means for moving the ring reflector~ in a selected displacement ratlo to maintain the cone of llght in focus a~ dif~erent angles of incidence.
In a ~pecific example of a system in accordance with the invention, a vision system has an optical axis along which a camera views an object through a magni~ication system. X, Y
and Z axis poæitloning is provided between the camera and the i~-em being examlned. A ring light source comprising a cylindrical array of optical fibers, energizable ln quadrants, is disposed concentric with khe optical axis, encompassing the lenæ magnificatlon system. The optical f~bers in the ring light source generate individually diverging beams forming a hollow cylindrical sheet of light directed downwardly ~oward the ob~ect 3~3~
under examillation. The light is reElected o~f a reElecting surface of paraboLic cross section on the inner ring, substantially radially outwardly toward a curved reflecting surface on the second outer ring. The second reflecting surface S is a toroidal segment that has a circular cross section to direct the light down to a common focal point, dependent upon the region of incidence on the second reflecting surface.
difEerential drive mechanism is coupled to the Z axis carriage to move the first and second reflector rings in the sam2 direction, but at diEferent rates of mOVeltlellt, 5uch that the focal.lengtll changes along with the angle oE inci~ence, and the ocal point remains ixed 'rheinechanisln moves separately from the Eocusing oE the camera,c;o as to provide great2r versatility.
In this arrangement, di~ferential motion is preferentially lS provided by a double rack system, with the pitch oE the teeth on the racks being in a selected ratio. Drive and idler gears between opposing racks enable the two racks to be moved in the selected ratio by a single motor, and without requiring external bearings.
- Brief Description oL the Drawings A better understanding may be had by reference to the Eollowing description, taken in con~unction with the accomparlying drawillgs, in which:
Fig. 1 is a perspective view, partially broken away, oE a vision system incorporating an illumination system in accordance with the invention;
Fig. 2 is a perspective fragmentary view of a portion of the arrangement of Fig. l;
Fig. 3 is a side sectional view of a portion oE the structur~ of Fig. 2;
3Z3;~
~, Fig. 4 is a ~ragrnentary view of a ~ortion o~ a di~ferential driv~ mechanism used in the m~cllanism of Figs. 2 and 3;
Fig. 5 is an end view of the structure oE Fig. ~; and Fig, 6 is a ~impLi~Le~ dep.. ction o~ variations in the angle of inci,-lence with di~ferent positions of the reElectors in the system of Figs. 1-5.
Detailed Description o~ the Invention A vision system 10 in accordance with the invention, as seen in Figs. 1 and 2, comprises a base console 12 having a temperature stable Elat granite table 13 on which a stage 1 i.s movable in the Y direction under control of a dri~e 15, comprising a motor and lead screw is mounted to place a product 16, indical:ed only generally, to be inspected at a given position in a viewing zone. A vertically Inountecl camera 17 points down at the view.ing zone through a magniEying lens systern 18. The camera 17 i~ mounted on a Z axis support 19 that is driven in the vertical direction by a Z axis motor 20 50 that the camera can focus on particular regions and surfaces. The camera 17 and Z axis support 19 are stably mounted on an X axis carriage 22 that is mounted on a stable vibration free bridge 23 spanning the v1ewing region above the.platform 14. The carriage 22 is translated In the horizontal plane by a drive 24 comprising a motor and lead screw. Both the drives 15 and 24 as well as the Z axis drive motor 20 are controlle~ by signals from a processor 25, which is typicalLy programmed to position the pro~uct 16 at given X and Y axis,positions relative to the camera 17 and also to ~ocusona particular level at the object. ~n illumination system 30 having elements concentric with the opt.ical axis is mounted conjointly with the camera 17 and lel-s sys~em 13 on the .r Z axis support 19.
~L~93~3;~
The illumination system 30, referring now to Figs. 2-5 as well as Fig. 1, includes a remote light source 32 on the console coupled through a Elexible optical Eiber harness 3~
having many individual optical fibers to a light ring 36 that is disposed about the lower end oE the ]ens system 18 an~
concelltric with the optical axis. As seen in the sectional view oE Fig. 3, the ends o~ tne individual optical fibers 38 are fanned out from a parallel core into a cylin~rical pattern in which the Eibers are paralleL and adjacent around the cylinder.
The light emanatin~3 from the ends oE the Eibers 38 collectively generates .~ hollow cylindQr or sileatll of light directed down towar~ the l~roduct 16. ~lowever, the light Erom each fiber end diverges at an angle of about 62 in thi3 instance, this angle varying in de~endence on the precision ot the end flat. The lS remote light ~ource 32 has our separate source~ in thi~ example, each controlling light to a different(luadrallt at the illuminator 30 and each controlled by the proce~sor 25.
Below the light ring 36, a Eir~t reElector ring 42 i3 movably mounted along the optical axis and includes a first reflector surface ~4 which is parabolic in cro~s section. The focal point of the parabola is chosen relative to the angle of ~ivergence o~ light from the fibers, to provi~e substantial collimation. Because the parabolic reflector sur~ace 4~ is in the path oE the downwardly directed light cylinder, it deflects the light radially outwar~ly from th2 circumEerence of the reElector surface 4~ to form what may be called a fan of light concentric with the optical axis of the camera 17. Thus the Eirst re-Elector ring 42 acts as a light collector as well as a light path diverter because of the parabolic sur~ace. The first reflector ring is in the form ot a surface o~ revolution whose body includes a waist section Eor receiving the li~ht ring 36.
~293;232 The outwardly directed light pattern impinges on a second reflector ring 46 outside the first ring 42, and relati-vely movable with respect to it along the Z axis. The reflect-ing surface 48 of the second reflector ring 46 is o~ circular cross section, as seen in Fig. 3. A circular or spherical segment is adequate for present purposes, although a hyperbolic curve would be preferred where higher precision is needed. The position at which the substantially horizontal fan beam ~rom the first ref]ector ring 42 impinges on the curved second re-flector surface 48 determines the allgle o~ deflection downward toward a focal point, thus acting as an angle generator. The parabolic reflector sureace 44 substantially collimates the light from the optical fibers 38 t'hat ans out toward the curved surface 48.
A differential drive mechanism 50, 'best seen in Figs. 2, 3, 4 and 5, is mounted on the X axis carriage 22, and consequen-tly is independent of the Z axis position of the camera 17 and lens system 18. ~ motor 52 ~Fig. 2) independent-ly drives the mechanism 50 so as to control the position of the second ring 46. The positions of both rings 42, 46 are changed concurrently in a certain proportionality which maintains focus as well as changing the angle o~ incidence. To this end, a pair o~ rack and pinion mechanisms are mounted in side-by-side relation, with ~ second rack 54 having a given tooth pitch being coupled to the second ring 46 by an angle bracket 55 and a first rack 56 having a greater pitch being coupled to the first ring 42 by an extending arm 57. The racks 54, 56 are offset in adjacent planes within an encompassing housing 59 attached to the Z axis support 19 (Fig. 1). Parallelism is maintained by drive and idler gears coupled wlthin the housing .~,`
f ~3 Z3;~
at spaced apart regions between the racks 54, 56. The drive gears, as seen in Figs. ~ and 5, include a irst gear 62 coupled to the shaEt oE the motor 52 and engaging the second rack 54. The firs-t gear 62 drives an adjacent second gear 64 in its plane, which is clustered with a third gear 66 in the plane of the first rack 56, and meshing with -the teeth in the first rack 56. The first and third gears 62, 6G generate a differential movement determined by the ratio of the pitches of the two racks 54, 56, the gears 62, 6~ having like diameters.
Two idlers 68, 69 are arranged to engage the racks 54, 56 to maintain parallelism without bearings. With -this arrangement, the racks 54, 56 reciprocate within the housing 59 and the needed motions are effected without the necessity for bearing supports. As seen in Fig. 5, the racks 54, 56 are attached to slider rods 70 which slide within bushings 72 in the housing.
In the operation oE the system of Fig. 1, the sequence of operation for examination of a product 16 will typically commence with an operator controlling positioning of the Y a~is stage 14 and the X axis carriage 22 to view differ-ent portions of the product 16, as these sequences and posi-tions are stored in the processor memory. At each position focal planes are selected for the lens system 18 and camera 17 by positioning the Z axis support 19, and then a preferred angle of incidence is chosen Eor light ~rom the illumination system 30. As the necessary set points Eor each position are sequentially selected by the operator, the sequence is stored in memory for that product 16. As each li~e product 16 is placed on the stage 14 in position for analysis, software for the system runs through the se~uence in conventional fashion, ,~'' 3;~
- 8a - 73112-3 focusing on and illuminating each selected point or region of the part. If the taper in the hole of the product 16 is to be ~easured, let it be assumed that the upper surface is a larger diameter and the ~25~3Z3;i~
lower surface is a smaller diameter. The calnera 17 and Lens 18 are then focused on one end or the other, and th~ illumination system 30 is shi~ted to giv2 an optimum angle oE incidence for a sharp transition in light contrast between the inner diameter 5 of the hole and the surroun~ing background Then the other end of the hole can be examined in similar fashion, with the ~ocus end angle of incidenc~ changed to show the transition most clearly. ~
~s best seen in Fig. 6, the illuminating light from 10 the ends of the optical Eibers 38 in the light ring 36 provides a 360 closed sheath oE light, but the light is somewhat divergent. Con3equently, the parabolic first re~lector surface 44 collects the light and sub~tantially collimates it "lirecting it toward the second, angle generator surEace 48, Erom wllence 15 it i9 directed toward a cone to~lard a Eocal ~oint. ~s the angle oE inci~ence is changed, the two reflector rings 42, 46 are moved together, but with a varying gap between them. Thus the light Erom the Eir~st,collector surface 44 irnpingeson a different region oE the curved, angle generator surEace 48, to change the 20 angle of illcidence b~lt maintain the same focal point.
, By controlling the remote lightsource32to illuminate dlfEerent groups o~ tb~ optical Eibers 38, in quadrants around the light ring 36, the product 16 can be illurninated from diEEerent sides, as well as angles, improviny the versa-tility 25 of the system.
While there have been described and illustrated in the drawings, various Eorm3 and variations in accordance with the invention, it wiLl be appreciated tllat the invention is not limited thereto but ellcompasses all exempliEications within the 30 scop~ of the appended claims. r
Claims (18)
1. A system for illuminating a target object with focused light at varying angles of incidence relative to an optical axis and comprising:
a ring light source concentric with the optical axis and providing a hollow cylinder of light directed toward the object;
a first ring reflector having an outer surface of parabolic cross section in a path of the cylinder of light and reflecting the light into an outwardly disbursing pattern;
a second ring reflector having an inner surface of curved cross section disposed about the first ring reflector and concentric therewith in a path of the pattern reflected from the first ring reflector; and means for varying the spacing of the first and second ring reflector from the object including means for moving the second ring reflector differentially relative to the first.
a ring light source concentric with the optical axis and providing a hollow cylinder of light directed toward the object;
a first ring reflector having an outer surface of parabolic cross section in a path of the cylinder of light and reflecting the light into an outwardly disbursing pattern;
a second ring reflector having an inner surface of curved cross section disposed about the first ring reflector and concentric therewith in a path of the pattern reflected from the first ring reflector; and means for varying the spacing of the first and second ring reflector from the object including means for moving the second ring reflector differentially relative to the first.
2. The invention as set forth in claim 1 above, wherein the ring light source comprises a ring of fiber optic elements arranged in arc segments, and the system further includes means for separately energizing the arc segments of the ring.
3. The invention as set fourth in claim 1 above, wherein the means for varying the spacing of the ring reflectors from the object comprises a pair of spaced apart racks having opposed teeth of different pitches, intercoupled gears disposed between the racks and engaging the teeth thereof, and motor means for driving the gears to provide differential movement of the racks, each rack being coupled to a different ring reflector.
4. The invention as set forth in claim 1 above, wherein the system further comprises an image camera directed along the optical axis and toward the object, and concentric with the ring light source and ring reflectors.
5. A method of examining an object with a vision system having an optical axis to enhance automatic recognition of distinctive features to be measured or identified automatically comprising the steps of:
illuminating an object with a conical sheath of light concentric with the axis of the vision system and focused on a selected point relative to the object to be analyzed; and changing an angle of incidence of the conical sheath of light while maintaining it in focus at the selected point.
illuminating an object with a conical sheath of light concentric with the axis of the vision system and focused on a selected point relative to the object to be analyzed; and changing an angle of incidence of the conical sheath of light while maintaining it in focus at the selected point.
6. A method as set forth in claim 5 above, further comprising the steps of changing a selected region of the object to be analyzed, and concurrently changing the angle of incidence and a focal position of the conical sheath of light or best illumination.
7. An illumination system for use with a viewing system for inspecting, measuring or recording an image of an object at an optical axis, comprising:
means providing a hollow cylindrical illuminating light pattern concentric with the optical axis and directed toward the object;
a first ring element having a curved reflecting surface concentric with the optical axis and reflecting the cylindrical light in a first direction, a second ring element having a curved reflecting surface in a path of the light reflected from the first curved reflecting surface and reflecting the light into a conical illumination pattern; and means coupled to move the first and second ring elements along the optical axis with differential motion.
means providing a hollow cylindrical illuminating light pattern concentric with the optical axis and directed toward the object;
a first ring element having a curved reflecting surface concentric with the optical axis and reflecting the cylindrical light in a first direction, a second ring element having a curved reflecting surface in a path of the light reflected from the first curved reflecting surface and reflecting the light into a conical illumination pattern; and means coupled to move the first and second ring elements along the optical axis with differential motion.
8. The invention as set forth in claim 7 above, wherein the reflecting surface of the first ring element has a paraboloidal curvature and the reflecting surface of the second ring element has a substantially circular curvature.
9. The invention as set forth in claim 8 above, wherein the means for moving the first and second ring elements along the optical axis comprises means for moving the second ring element at a rate which is greater than the movement of the first element, whereby the light reflected from the reflecting surface of the second ring element varies in angle of incidence but the focal point of the conical illumination pattern remains the same.
10. The invention as set forth in claim 9 above, wherein the means providing a light pattern comprises a plurality of optical fibers arranged in a circular pattern concentric with the optical axis and having their ends along parallel lines.
11. The invention as set forth in claim 9 above, wherein the reflecting surface of the first ring element is at a smaller diameter than the reflecting surface of the second ring element and wherein the means for moving the ring elements comprises a pair of parallel racks having facing teeth of different pitches and drive gear means disposed between the racks and engaging the teeth, and drive motor means coupled to the drive gear means.
12. A light system for providing light at variable angles of incidence on an object to be viewed at a focal plane along a viewing axis perpendicular to the viewing axis, comprising:
a first body in the form of a surface of revolution concentric with the viewing axis and having an outer reflecting flange on a side opposite the focal plane, the reflecting flange defining a first reflecting surface that is parabolic in cross section;
means disposed about the first body and providing a circular light source concentric with and directed onto the first reflecting surface, the light from the source diverging within a beam angle and the focal point of the first reflecting surface being selected to collimate light from the source;
a second body in the form of a surface of revolution concentric with the viewing axis and having an inner reflecting flange on a side facing the focal plane, the reflecting flange defining a second reflecting surface that approximates a circular arc in cross section and reflects light inwardly toward the viewing axis;
means coupled to the first and second bodies for moving such bodies along the viewing axis in a selected displacement ratio such that the light reflected from the second surface focuses at the focal plane.
a first body in the form of a surface of revolution concentric with the viewing axis and having an outer reflecting flange on a side opposite the focal plane, the reflecting flange defining a first reflecting surface that is parabolic in cross section;
means disposed about the first body and providing a circular light source concentric with and directed onto the first reflecting surface, the light from the source diverging within a beam angle and the focal point of the first reflecting surface being selected to collimate light from the source;
a second body in the form of a surface of revolution concentric with the viewing axis and having an inner reflecting flange on a side facing the focal plane, the reflecting flange defining a second reflecting surface that approximates a circular arc in cross section and reflects light inwardly toward the viewing axis;
means coupled to the first and second bodies for moving such bodies along the viewing axis in a selected displacement ratio such that the light reflected from the second surface focuses at the focal plane.
13. A system as set forth in claim 12 above, wherein the first reflecting surface forms an outwardly directed sheet of light and the second reflecting surface s disposed outside the first reflecting surface.
14. A system as set forth in claim 13 above, wherein the light source comprises a plurality of optical fibers having fiber ends disposed in parallel to define a cylinder concentric about and parallel to the viewing axis.
15. A system as set forth in claim 14 above, wherein the light source further comprises means for energizing sets of the optical fibers to provide illumination of the object from different directions as well as from all directions about the object.
16. A vision system comprising:
a stable base having a horizontal upper surface;
a stable bridge scanning the upper surface in an X
axis direction and overlying a viewing zone on the base;
platform means on the upper surface of the base for receiving an object to be viewed, the platform means including Y axis drive means for providing horizontal movement in the Y
direction;
X axis carriage means mounted on the bridge and including X axis drive means for providing horizontal movement in the X direction;
Z axis carriage means mounted on the X axis carriage means and including drive means for providing vertical movement;
electronic camera means, including magnification means, mounted on the Z axis carriage means and oriented along an optical axis to view the viewing zone;
illuminator means disposed concentrically about the electronic camera means and the optical axis for providing a cone of light on the object to be viewed, the illuminator means comprising a pair of ring reflectors; and illuminator drive means mounted on the Z axis carriage means and coupled to the illuminator means for moving the ring reflectors in a selected displacement ratio to maintain the cone of light in focus at different angles of incidence.
a stable base having a horizontal upper surface;
a stable bridge scanning the upper surface in an X
axis direction and overlying a viewing zone on the base;
platform means on the upper surface of the base for receiving an object to be viewed, the platform means including Y axis drive means for providing horizontal movement in the Y
direction;
X axis carriage means mounted on the bridge and including X axis drive means for providing horizontal movement in the X direction;
Z axis carriage means mounted on the X axis carriage means and including drive means for providing vertical movement;
electronic camera means, including magnification means, mounted on the Z axis carriage means and oriented along an optical axis to view the viewing zone;
illuminator means disposed concentrically about the electronic camera means and the optical axis for providing a cone of light on the object to be viewed, the illuminator means comprising a pair of ring reflectors; and illuminator drive means mounted on the Z axis carriage means and coupled to the illuminator means for moving the ring reflectors in a selected displacement ratio to maintain the cone of light in focus at different angles of incidence.
17. The invention as set forth in claim 16 above, wherein the system includes processor means coupled to control the X axis drive, Y axis drive, Z axis drive and illuminator drive means in a selected sequence of positions to focus the camera means on selected positions on the object and to concurrently illuminate the object with light at preferred angles of incidence.
18. The invention as set forth in claim 17 above, wherein the illuminator means comprises light source means providing a concentric light pattern about the viewing axis, and wherein the ring reflectors comprise a first, inner, reflector ring having a parabolic reflecting surface and a second, outer reflector ring having a generally circular reflecting surface, the parabolic reflecting surface collecting and collimating light from the concentric light pattern and the circular reflecting surface and its displacement along the optical axis relative to the parabolic reflecting surface establishing the angle of incidence of light directed toward the object.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/798,632 US4706168A (en) | 1985-11-15 | 1985-11-15 | Systems and methods for illuminating objects for vision systems |
| US798,632 | 1985-11-15 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1293232C true CA1293232C (en) | 1991-12-17 |
Family
ID=25173878
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000520483A Expired - Lifetime CA1293232C (en) | 1985-11-15 | 1986-10-15 | Systems and methods for illuminating objects for vision systems |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4706168A (en) |
| EP (1) | EP0223556B1 (en) |
| JP (1) | JPS62168125A (en) |
| CA (1) | CA1293232C (en) |
| DE (1) | DE3686861T2 (en) |
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| US8085295B2 (en) * | 2007-10-26 | 2011-12-27 | Mitutoyo Corporation | Controllable micro light assembly |
| CN106736869B (en) * | 2016-12-09 | 2018-10-16 | 大连理工大学 | A kind of observation procedure of mechanical processing high speed photomicrography |
| JP6976914B2 (en) * | 2018-09-14 | 2021-12-08 | 株式会社東芝 | Optical inspection equipment |
| WO2020109237A1 (en) * | 2018-11-26 | 2020-06-04 | Zkw Group Gmbh | Vehicle vision system with adaptive reversing light |
| IT201900005534A1 (en) * | 2019-04-10 | 2020-10-10 | Doss Visual Solution S R L | ILLUMINATOR FOR A VISION GROUP OF AN OPTICAL INSPECTION MACHINE FOR THE QUALITY CONTROL OF PARTS |
| WO2021083803A1 (en) * | 2019-10-28 | 2021-05-06 | Signify Holding B.V. | Color mixing with total internal reflector and ring reflector |
| FR3108965B1 (en) | 2020-04-07 | 2022-04-29 | Arteffect | Extended Aperture Light Device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4321353Y1 (en) * | 1965-09-18 | 1968-09-07 | ||
| US3506836A (en) * | 1966-08-23 | 1970-04-14 | Amp Inc | Optical programmer with optic fiber means for indicating operating intelligence for equipment controlling means |
| DE1913711A1 (en) * | 1968-03-19 | 1969-10-09 | Olympus Optical Co | Lighting system for optical instruments |
| US3770342A (en) * | 1971-05-07 | 1973-11-06 | R Dudragne | Device for lighting and examining a cavity |
| JPS566169B2 (en) * | 1972-10-25 | 1981-02-09 | ||
| US4037096A (en) * | 1974-08-09 | 1977-07-19 | American Sterilizer Company | Illuminator apparatus using optical reflective methods |
| US4109304A (en) * | 1976-02-23 | 1978-08-22 | Khvalovsky Vladimir Vasilievic | Device for coherent lighting of objects |
| DD138110A1 (en) * | 1978-07-27 | 1979-10-10 | Horst Riesenberg | REQUIRED LIGHTING DEVICE FOR MICROSCOPES |
| US4288844A (en) * | 1978-08-24 | 1981-09-08 | American Sterilizer Company | Electrically focused surgical light |
| DE2854684C2 (en) * | 1978-12-18 | 1980-10-30 | Original Hanau Heraeus Gmbh, 6450 Hanau | Light guides, in particular for operating or examination lights |
| BE875482A (en) * | 1979-04-11 | 1979-10-11 | Chandesais Jean L J | IMPROVED RING LIGHT FOR MICROSBUIES |
| JPS55167221U (en) * | 1979-05-18 | 1980-12-01 | ||
| JPS566169U (en) * | 1979-06-27 | 1981-01-20 | ||
| DD145805B1 (en) * | 1979-08-27 | 1982-06-30 | Johannes Grosser | LIGHTING ARRANGEMENT FOR MICROSCOPES |
| DE3012340C2 (en) * | 1980-03-29 | 1984-06-20 | W.C. Heraeus Gmbh, 6450 Hanau | Operating light |
| US4392182A (en) * | 1981-06-12 | 1983-07-05 | Solid Photography, Inc. | Arrangement for scanning points in space |
| US4494868A (en) * | 1982-08-18 | 1985-01-22 | Eastman Kodak Company | Rangefinder device with focused elongated light source |
| US4529316A (en) * | 1982-10-18 | 1985-07-16 | Robotic Vision Systems, Inc. | Arrangement of eliminating erroneous data in three-dimensional optical sensors |
| FR2548796B1 (en) * | 1983-07-08 | 1985-11-22 | Comp Generale Electricite | OPTICAL DEVICE FOR DETERMINING THE POSITION AND SHAPE OF THE SURFACE OF AN OBJECT |
| US4530036A (en) * | 1984-01-20 | 1985-07-16 | Conti Mario W | Object illumination apparatus |
| US4617619A (en) * | 1985-10-02 | 1986-10-14 | American Sterilizer Company | Reflector for multiple source lighting fixture |
-
1985
- 1985-11-15 US US06/798,632 patent/US4706168A/en not_active Expired - Lifetime
-
1986
- 1986-10-15 CA CA000520483A patent/CA1293232C/en not_active Expired - Lifetime
- 1986-11-11 JP JP61268462A patent/JPS62168125A/en active Granted
- 1986-11-12 DE DE8686308823T patent/DE3686861T2/en not_active Expired - Lifetime
- 1986-11-12 EP EP86308823A patent/EP0223556B1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62168125A (en) | 1987-07-24 |
| DE3686861T2 (en) | 1993-04-15 |
| US4706168A (en) | 1987-11-10 |
| EP0223556A2 (en) | 1987-05-27 |
| JPH039445B2 (en) | 1991-02-08 |
| EP0223556A3 (en) | 1989-04-12 |
| DE3686861D1 (en) | 1992-11-05 |
| EP0223556B1 (en) | 1992-09-30 |
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| Date | Code | Title | Description |
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| MKLA | Lapsed |