CN1308725C

CN1308725C - LED Opening and closing controlling method for scanner

Info

Publication number: CN1308725C
Application number: CNB2004100036245A
Authority: CN
Inventors: 李达义; 张荣乔; 潘新传; 王绮年; 王启南
Original assignee: Lite On Technology Corp
Current assignee: Lite On Technology Corp
Priority date: 2004-02-05
Filing date: 2004-02-05
Publication date: 2007-04-04
Anticipated expiration: 2024-02-05
Also published as: CN1651969A

Abstract

The present invention discloses an LED opening/closing controlling method applied to a scanner which uses an LED used as a light source of the scanner to replace a cold-cathode fluorescence lamp tube and solves the defect that machine warming-up time is overlong in the prior art. The present invention controls the LED to carry out an opening/closing action by optical signal frequency read by the scanner, and accordingly an intermittent heat dispersion function is reached.

Description

The light emitting diode that is applied to scanner opens and closes control method

Technical field

The present invention relates to a kind of light emitting diode that is applied to scanner and open and close control method, particularly relate to the method that a kind of frequency that reads optical signalling by scanner opens and closes with the control light emitting diode.

Background technology

Scanner is the input equipment that is widely used in computing machine except that keyboard and mouse.You can utilize scanner input photo to set up the electronic album of oneself; Import various pictures and set up the website of oneself; Scanning hand-written letter sends to replace facsimile recorder with E-mail again; Can also utilize scanner to cooperate the content of OCR software input newspaper or books, exempt the arduous of Chinese characters for keyboard inputting.All these have showed the function that scanner is out of the ordinary for us, and its let us has improved efficient at aspects such as office, study and amusements.

Process from the image digitazation of scanner, fluorescent tube emits beam, shine on the reflection contribution on the scanner glass plate, difference according to the different local bright dark degree of contribution, form the strong and weak reflection ray that does not wait, then by a series of catoptrons, focus on the charge-coupled device (CCD) of the camera lens other end, CCD is converted to corresponding electric signal with optical signalling, it is simulating signal, these signals finally are converted into the digital signal that computing machine can be discerned by A/D converter, then through different interfaces, Enhanced Parallel Port EPP (Enhanced Parallel Port) for example, USB (universal serial bus) USB (Universal Serial Bus) or small computer system interface SCSI (Small Computer System Interface) are sent to computing machine.

A/D converter is the semiconductor subassembly that analog quantity (Analog) is changed into digital quantity (Digital).The electric signal that obtains from CCD is the simulate signal corresponding to the image light and shade, and image is by secretly representing that to bright variation they are continually varyings with different potentials from low to high, promptly so-called analog quantity in other words.

Yet for scanner, light source is very important, because the light of being experienced on the CCD, all comes from the fluorescent tube of scanner self.Impure or the colour cast of light source can directly have influence on scanning result.Specialty scanner or some high end home or commercial scanners, before scanning, can detect the light intensity that fluorescent tube sends automatically, particularly when scanner just starts, because fluorescent tube does not enter steady state (SS), scanner has certain preheating time, have only the light intensity of working as enough to reach standard, the light source detection sensor in the machine just can send by instruction.And scanner at this moment could scan with the duty of the best, because if the fluorescent tube light intensity can't effectively show the dark portion details in the original copy inadequately.

And the lamp source that traditional scanner uses when the major defect of this kind fluorescent tube promptly is to start shooting at every turn, needs with briliancy with fluorescent tube slowly be promoted to stable status one period foregoing preheating time all based on cathode fluorescent tube (CCFL).This section preheating time needed do not wait in about 1-3 minute at normal temperatures, and is not only tediously long and make the user be difficult to stand, and often cause the user to take for system when machine and handling return, this situation under low temperature environment especially obviously and seriously.

In view of this, just the someone proposes that (Light Emitting Diode is LED) as the conception of scanner light source with light emitting diode.Though light emitting diode can effectively reduce the stand-by period before the cold machine scanning, there is the not enough and serious disappearance of heat dissipation problem of briliancy.

Summary of the invention

Fundamental purpose of the present invention is provides a kind of light emitting diode that is applied to scanner to open and close control method, to solve LED heat radiating problem important disadvantages.

For achieving the above object, the light emitting diode that the present invention is applied to scanner opens and closes control method, be with the light source of white light emitting diode as scanner, and scanner output has a pulse to read the frequency of optical signalling with the gated sweep instrument, and then white light emitting diode promptly reads the action of frequency to open and to close of optical signalling according to scanner.

More specifically, when pulse signal was positioned at electronegative potential, light emitting diode was promptly opened and is emitted beam, and made scanner can read optical signalling.Otherwise when pulse signal was positioned at noble potential, light emitting diode was promptly closed and is not emitted beam, and scanner also stops to read optical signalling.So can reach the purpose of the intermittent heat radiation of light emitting diode.

In addition, scanner passes through a charge-coupled image sensor (CCD, Charge Couple Device) to read optical signalling.

For making purpose of the present invention, structural attitude and function thereof are had further understanding, existing conjunction with figs. is described in detail as follows.

Description of drawings

Fig. 1 is that the light emitting diode of known scanner opens and closes the control first embodiment synoptic diagram;

Fig. 2 is that the light emitting diode of known scanner opens and closes the control second embodiment synoptic diagram;

Fig. 3 opens and closes the control first embodiment synoptic diagram for the light emitting diode of scanner of the present invention;

Fig. 4 opens and closes the control second embodiment synoptic diagram for the light emitting diode of scanner of the present invention; And

Fig. 5 opens and closes control the 3rd embodiment synoptic diagram for the light emitting diode of scanner of the present invention.

Embodiment

Please refer to shown in Figure 1ly, this figure is that the light emitting diode of known scanner opens and closes the control first embodiment synoptic diagram, as shown in the figure:

This known scanner is as light source with a white light LEDs, and output has a pulse, white light LEDs is for lighting constantly, then when pulse signal is come electronegative potential, the light that the image sensor of scanner promptly is received from white light LEDs and is sent, and read wherein red signal light, when treating that pulse signal is come noble potential, scanner promptly stops to read optical signalling, when pulse signal is come electronegative potential again, scanner then reads the green optical signal in the light of white light LEDs, then when pulse signal is come noble potential again, the image sensor of scanner just stops to read optical signalling again, and when pulse signal was come electronegative potential again more by the time, scanner promptly began to read the blue light signal and returns to noble potential up to pulse signal.So, promptly finish the circulation that scanner reads R/G/B three primary colors optics signal, then scanner can read the reception data continuously by constantly repeating this circulation.

Then, please refer to shown in Figure 2ly, this figure is that the light emitting diode of known scanner opens and closes the control second embodiment synoptic diagram, as shown in the figure:

This known scanner is identical with the scanner described in first embodiment, with a white light LEDs as light source, and output has a pulse, white light LEDs is for lighting constantly, then when pulse signal is come electronegative potential, the light that the image sensor of scanner promptly is received from white light LEDs and is sent, and read wherein optical signalling.Different is, be when pulse signal is come electronegative potential, this scanner promptly reads red signal light, green optical signal and blue light signal continuously to finish a circulation, because the frequency of this scanner reading optical data is higher, therefore can have higher resolution.

Above-mentioned known scanner utilizes light emitting diode to replace cold cathode fluorescent lamp as light emitting source, though can effectively solve long disappearance preheating time, but because light emitting diode can produce high heat under long-time shinny situation, make scanner operation under the environment of high temperature, shortened the life-span of product like this.

Therefore, please refer to shown in Figure 3ly, this figure is that the light emitting diode of scanner of the present invention opens and closes the control first embodiment synoptic diagram, as shown in the figure:

This scanner with a white light LEDs as light source, and output has a pulse, when pulse signal during at noble potential, white light LEDs is closed and is not emitted beam, when pulse signal is come electronegative potential, white light LEDs is promptly opened to emit beam, and makes the image sensor of scanner be received from the light that white light LEDs sends, and reads optical signalling wherein.When treating that pulse signal is come noble potential again, white light LEDs is promptly closed and is not emitted beam, and scanner also stops receiving optical signal.

Scanner can be when each pulse signal be come electronegative potential, reads red signal light, green optical signal and blue light signal in the optical signalling in regular turn to finish a circulation.Or improve the frequency that scanner reads optical signalling, when each pulse signal was come electronegative potential, scanner promptly once read red signal light, green optical signal and blue light signal finishing a circulation, thereby improves the resolution of scanner.

Refer again to shown in Figure 4ly, this figure is that the light emitting diode of scanner of the present invention opens and closes the control second embodiment synoptic diagram, as shown in the figure:

When pulse signal was positioned at electronegative potential, white light LEDs also can read the raising of optical signalling frequency according to scanner, and the action of in an electronegative potential pulse signal, repeatedly opening and closing.

In sum, light emitting diode is just opened when scanner reads optical signalling and is emitted beam, when the image sensor of scanner stops to read optical signalling, light emitting diode is promptly closed and is not emitted beam, make light emitting diode when closing, to dispel the heat, and the frequency of light emitting diode open and close reads the frequency of optical signalling according to scanner and changes, then utilize different switching frequencies to cooperate different resolution, produce different electric current and briliancy, as the function of intermittent heat radiation, can effectively improve the efficient of product simultaneously.

Herein, the image sensor of scanner is charge-coupled image sensor (CCD, Charge CoupleDevice) that the surface light electrical part that utilizes microelectric technique to make can be realized photoelectric converting function.CCD is widely used in video camera, digital camera and scanner, that only use in the video camera is dot matrix CCD, comprise that promptly x, y both direction are used to absorb plane picture, and what use in the scanner is linear CCD, it has only direction of x, and the y scanning direction is finished by the mechanical hook-up of scanner.Many photosensitive units are arranged on the CCD chip, and they can convert different light to different electric charges, thereby form the charge image of corresponding original copy light image.

Please refer to shown in Figure 5ly again, this figure is that the light emitting diode of scanner of the present invention opens and closes control the 3rd embodiment synoptic diagram, as shown in the figure:

Scanner of the present invention except that can white light LEDs as the light source, also can red-light LED, green light LED and blue-ray LED be as light source, then when the image sensor of scanner will receive the optical signalling of ruddiness, red-light LED is promptly done suitable open and close according to the data read frequency of scanner, in like manner as can be known, green light LED and blue-ray LED also are same start patterns.

Though the present invention with aforesaid preferred embodiment openly as above; yet it is not in order to limit practical range of the present invention; any those of ordinary skill of knowing this technology; the equalization of being done in not breaking away from spirit of the present invention and claim changes and modifies; be all claim of the present invention and contain, therefore scope of patent protection of the present invention should be with within claims of the present invention scope required for protection.

Claims

1. a light emitting diode that is applied to scanner opens and closes control method, and this scanner, is characterized in that as light source with light emitting diode:

This light emitting diode is a white light emitting diode, and reads the action of frequency to open and to close of optical signalling according to this scanner.

2. the light emitting diode that is applied to scanner as claimed in claim 1 opens and closes control method, and wherein this scanner reads the frequency of optical signalling and the keying of this white light emitting diode by a pulse with control.

3. the light emitting diode that is applied to scanner as claimed in claim 1 opens and closes control method, and wherein at pulsatile once in the time interval, this white light emitting diode is once opened for this scanner and read optical signalling.

4. the light emitting diode that is applied to scanner as claimed in claim 1 opens and closes control method, and wherein at pulsatile once in the time interval, this white light emitting diode carries out repeatedly opening and closing action and reads optical signalling for this scanner.

5. open and close control methods as claim 3 or the 4 described light emitting diodes that are applied to scanner, wherein at pulsatile once in the time interval, this scanner reads ruddiness optical signalling, green glow optical signalling and blue light optical signal.

6. the light emitting diode that is applied to scanner as claimed in claim 1 opens and closes control method, wherein this scanner by a charge-coupled image sensor to read optical signalling.

7. open and close control method as claim 3 or the 4 described light emitting diodes that are applied to scanner, wherein when this pulse was positioned at noble potential, this light emitting diode was closed, and this scanner stops to read optical signalling.