JPH02199448A - Exposing device - Google Patents

Abstract

PURPOSE:To stabilize the color balance of an output image at any time by adjusting an impressing voltage to a light source based on the spectral distribu tion of light reflected from a reflection reference plate. CONSTITUTION:When an original is placed on an original platen glass 2 to push a start button, the glass 2 moves to the right side and stops in the position where the light edge of the glass 2 faces to a light source. Then, a halogen lamp 3 moves to the left side while it lights on. Additionally, a white reference plate 51 is provided on the left edge of the back of the glass 2. The irradiating light from the lamp 3 is reflected by the reference plate 51 and is made incident on a sensor 50. The sensor 50 detects the spectral distribution of the reflected light and inputs the detected value to a control means. The control means calculates the impressing voltage to the lamp 3, and an adjusting mechanism adjusts a resistance value. Therefore, light quantity emitting from the lamp 3 becomes constant and exposing quantity comes to a constant value.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an exposure device, and particularly to an image forming device capable of forming a full-color copy image using a photosensitive recording medium such as microcapsule paper. The present invention relates to an applied exposure apparatus.

[Conventional technology]

An overview of this type of image forming apparatus is generally described below. That is, the document is scanned by irradiating the document with light from an exposure lamp such as a halogen lamp and by moving the document table cover and document table glass.

2. The reflected light from the scanning of the original is guided by various optical systems to an exposure table in the center of the image forming apparatus, where it forms an image on one surface of the supplied photosensitive recording medium. Exposing a photosensitive recording medium.

In such an image forming apparatus, an image is formed on the assumption that the light amount and illuminance of the exposure lamp are constant, and there is no separate means for detecting the color temperature of the light irradiated by the exposure lamp. Ta.

[Problem to be solved by the invention]

However, there are individual differences in exposure lamps, and there are variations in the exposure lamps, and the exposure lamps may fluctuate over time. When such a change in the characteristics of the exposure lamp occurs, the spectral intensity of the irradiated light changes, resulting in a change in the color balance of the output image, causing a problem in which the original image cannot be accurately reproduced.

The present invention has been made in consideration of the above circumstances, and provides an exposure device that can be applied to an image forming apparatus that can always obtain an output image with stable color balance even when there are variations in the light source or changes over time. The purpose is to provide.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a sensor that detects the spectral distribution (color temperature) of light emitted from a light source, and a light source that adjusts the spectral distribution from the light source to a predetermined value based on the detected value from the sensor. and control means for adjusting the voltage applied to the.

In this case, the control means stores data for correcting the voltage applied to the light source corresponding to the spectral distribution, and adjusts the exposure amount by comparing the spectral distribution detected by the sensor with the correction data. Also good.

[Effect]

In the above configuration, since the voltage applied to the light source is adjusted based on the spectral distribution detected by the sensor, the spectral distribution is adjusted by direct control of the light source.

〔Example〕

The present invention will be explained below based on specific examples.

FIG. 1 shows an embodiment of the present invention, which includes a DC power source 70, a light source 71 that emits light when a voltage is applied by the power source 70, and a variable resistor 72 that adjusts the voltage applied to the light source 71. A circuit is formed, and the light source 71 is provided with a reflecting member 73 that reflects the emitted light. Also, near the light source 71, there is a spectral distribution (color temperature) of reflected light.
A sensor 50 for detecting is provided, and a control means 60 is connected to this sensor 50. A microcomputer is used as the control means 60, and includes a CPU 61 and a ROM 62.
, a RAM 63, and an I10 port 64, which are connected by a bus line 65. CPU6F
is for n1II control of exposure adjustment, and is stored in ROM62.
This exposure adjustment progera l and correction data for exposure adjustment are stored in . Correction data for this exposure adjustment is developed in the RAM 63. This correction data consists of a table etc. in which the spectral distribution of light from the light source corresponds to the voltage applied to the light source 71.
The value is set so that the exposure amount of 1 is constant. The spectral distribution detected by the sensor 50 is input to the I10 port 64, and the input of this detection value causes the CPU 61 to
An applied voltage value that makes the exposure amount of the light source constant is calculated from the correction data in the OM 62 and output to the I10 boat 64. An adjustment mechanism 66 for adjusting the resistance value of the variable resistor 72 is connected to the I10 boat 64.
adjusts the resistance value to match the applied voltage output from the CPU 61. As a result, the light source 71 always emits a light amount that provides a predetermined spectral distribution (color temperature), so that stable exposure adjustment can be performed.

FIG. 2 shows an example in which the present invention is applied to a color copying machine. A top plate portion of the copying machine 40 is provided with a document table glass 2 on which a document is placed, and a document table cover 1 that covers the document table glass 2 in an openable and closable manner so as to be movable left and right. Further, on the lower right side of the document table glass 2, a light source 3 for irradiating light onto the document is provided. This light source 3 is similar to the light source 71 in FIG. It is designed to illuminate the entire document with light. In this embodiment, a halogen lamp is used as the light source 3, and the halogen lamp 3 is surrounded by a semi-cylindrical reflecting mirror 4. Also,
In order to use the light emitted from the halogen lamp 3 to irradiate the original with high efficiency, a beam flap 5 is placed on the left side of the lamp 3 to reflect the light that is not directly directed toward the original and use it again to irradiate the original. .

On the other hand, an exposure table 19 is disposed at the center of the inside of the copying machine 40, and between this exposure table 19 and the halogen lamp 3, there is a filter 8 for adjusting the color tone of the copied image and a light condensing filter 8. A lens 9 (= supported by an I plate 10, and a pair of reflective mirrors for adjusting the optical path length and focus between the lens 9 and the exposure table 19)
] is supported by the plate (=I plate) 2 so that it can be adjusted in position 5.1.Here, the filter 8 is used to detect the RED, GREENSBL, and RED lights of the reflected light irradiated from the halogen lamp 3 and reflected by the original.
It adjusts the light intensity of each color of the UE, and is inserted into the optical path of reflected light.

In such a configuration, the light emitted from the halogen lamp 3 is reflected by the original, and the reflected light passes through an optical path consisting of the filter 8, the lens 9, and a pair of reflective mirrors 11, and reaches the exposure table 19. A sensor 50 that detects the spectral distribution of reflected light on this optical path is arranged close to the optical path. The sensor 50 in this embodiment is provided between the halogen lamp 3 and the filter 8, and detects the spectral distribution of the irradiated light from the halogen lamp 3 and the reflected light from the platen glass before they enter the filter 8. It is designed to be detected. Such a sensor 50 is appropriately selected according to the type of light source, and when the light source is a halogen lamp as in this embodiment, the RED, GR of the halogen lamp is selected.
A color temperature sensor is used to detect the amount of light of each color, EEN and BLUE.

As described later, such a sensor 50 outputs the detected value of the detected spectral distribution to the control means 60 (see FIG. 1),
The control means 60 controls the nozzle lamp 3 based on this detected value.
Adjust the voltage applied to the In FIG. 1, reference numeral 51 is a white reference plate that is attached to the left end of the document glass 2 and extends in a direction perpendicular to the moving direction of the document glass 2. The spectral distribution of the reflected light is detected and the detected value is output to the control means 60.

A fan 6 and a looper 7 are provided on the right side of the light source 3 to cool the light source 3 by introducing outside air.

A cartridge 14 is removably housed inside the copying machine main body 40, and a winding shaft 25 is rotatably supported. Further, the cartridge 14 stores in a wound state a long microcapsule paper 37 carrying a large number of microcapsules containing dye for color copying and the like. Then, by the rotation of the plurality of feed rollers 15 and 17, the microcapsule paper 37 is pulled out from the cartridge 14 and then wound around the winding shaft 25, during which time,
A portion passing through the lower surface of the exposure table 19 is exposed to form a latent image of the original. Reference numeral 16 is a light-shielding cover, which covers the microcapsule paper 3 pulled out from the cartridge 13.
This prevents exposure to light as described in Item 7.

A cassette 32 containing a sheet of developing paper 38 having a certain size is removably attached to the copying machine main body 40 below one of the exposure tables.
9 and the winding shaft 25, a pressure developing device 20 is provided between the exposed portion of the microcapsule paper 37 and the color developing paper 3.
8 are brought into pressure contact within the pressure developing device 20, whereby a color image based on the latent image on the microcapsule paper 37 is formed on the color developer paper 38. The color developer paper 38 is made by coating a color developer on a base material and forming a heat-melting surface resin layer on the color developer. Examples include PUT (polyethylene terephthalate).

This color developing paper 38 is supplied from the cassette 32 to the pressure developing device 20 by the rotation of the half-moon roller 33.

A plurality of feed rollers 34 for transporting the developing paper 38 toward the pressure developing device 20 and a registration gate 35 for positioning the leading end of the developing paper 38 are provided between the cassette 32 and the pressure developing device 20. On the paper feeding side of the developing device 20, microcapsule paper 37 to color developer paper 38 are stored.
A peeling +1u roller 23 is provided for peeling off. Here, the pressure developing device 20 includes a small-diameter roller 21 and a backup roller 31, and when the developer paper 38 and the microcapsule paper 37 are in close contact with each other, these rollers 21.
31, pressure is applied, and this pressure destroys the unexposed microcapsules and leaves the color developing paper 3.
An image is formed on 8. Then, the microcapsule paper 37 and the color developer paper 3 that come out of the pressure developing device
8 is conveyed by a capsule paper feed roller 22, and a peeling roller 23 separates the microcapsule paper 37 upwardly and the developer paper 38 in the perpendicular direction. After color development is promoted by the heat fixing device and an image is formed on the color developer paper 38, the paper is conveyed to the paper discharge tray 27 with the image side facing up. This heat fixing device has a hollow heat roller 29 having a heater 30 inside.
and a color developing paper feed roller 28. On the other hand, the separated microcapsule paper 37 is held by the meandering adjustment roller 24.
It is then wound around the winding shaft 25.

Next, the operation of this color copying machine will be explained with reference to FIG.

After opening the document platen cover 1 and placing the original on the document platen glass 2, press the start button (not shown).The document platen glass 2 first moves to the right in FIG. The left end of the glass 2 stops at a position facing the light source. Thereafter, with the halogen lamp 3 turned on, the document table glass 2 is moved to the left. This manuscript glass 2
A white reference plate 51 is provided on the back side of the left end, and the light emitted from the halogen lamp 3 is reflected by this white reference plate 51. The sensor 50 detects the spectral distribution from the light reflected from the white reference plate 51 and outputs the detected value to the control means 60. The ROM 62 of the control means 60 stores data for correcting the voltage applied to the halogen lamp 3 corresponding to the spectral distribution value, and when the detected value from the sensor 50 is input, the correction data for the halogen lamp 3 is written based on the correction data. The voltage applied to is calculated. This calculated applied voltage is outputted from the control means 60 to the adjustment mechanism 66 and is applied to the variable resistor 7.
The resistance value of 2 is adjusted, so that the amount of light emitted from the halogen lamp 3 becomes constant, and the amount of exposure becomes a constant value.

Therefore, even if there are individual differences or variations over time in the halogen lamps 3, corrections are automatically made to keep the exposure amount constant.

After the color correction is completed in this way, the document platen glass 2 moves to the right again, and the light from the halogen lamp 3 is reflected by the document, passes through the filter 8, the lens 9, and the reflective mirror 11 to the exposure table 2. Microcapsule paper 37 on the bottom side
image is formed. At this time, the microcapsule paper 37 is moved to the left on the exposure table 19 at the same speed as the moving speed of the document table glass 2, so the image on the document is formed as a latent image on the microcapsule paper 37. Ru. Then, as the document platen glass 2 moves to the left, the suction rod 33
The developer paper 38 is taken out from the developer paper cassette I-32 and supplied to the pressure developing device 20 in a superimposed state with the exposed microcapsule paper 37, where the latent image on the microcapsule paper 37 is developed. The image is then transferred onto the color developing paper 38.

Thereafter, the developing paper 38 is thermally fixed by a thermal fixing device and then discharged from the copying machine 40 . On the other hand, pressure developing device 20
The microcapsule paper 37 that has passed through the winding shaft 2 is
It is wound up in 5. When the document platen glass 2 finishes moving to a position where its right end faces the light source, copying of the document is completed and the halogen lamp 3 is turned off.

〔Effect of the invention〕

As explained above, the present invention corrects the spectral distribution (color temperature) by directly adjusting the voltage applied to the light source based on the spectral distribution of the reflected light from the light source. Even if there are changes, it is possible to always obtain an output image with a stable color balance.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a sectional view of a copying machine to which the present invention is applied. 1... Original platen cover 2... Original platen glass, 3...
・Halogen lamp, 4... Reflector, 5... Reflector, 6... Fan, 7... Louver, 8... Filter, 9... Lens, 10... Lens mounting plate, 11...・
・Reflection mirror 12... Mirror mounting plate, 14... Cartridge, 15... Feed roller, 16... Light shielding cover 17... Feed roller, 19... Exposure stand, 20...
- Pressure developing device, 21... Small diameter roller, 22... Capsule paper feeding roller, 23... Peeling roller, 24...
- Meandering adjustment roller, 25... Winding shaft, 27... Paper ejection tray, 28... Paper ejection roller, 29... Heat roller, 30... Heater, 31... Backup roller, 32. ...Developer paper cassette, 33...Suction rod,
34... Developing paper feed roller, 35... Registration gate, 37... Microcapsule paper, 38... Developing paper, 40... Copying machine, 50... Sensor, 51... White reference plate , 60...control means, 70...power supply, 71...
- Light source, 72... Variable resistor, 73... Reflection section side. Applicant Yasushi Ishikawa Procedural Amendment Date 1989

Claims (1)

[Claims] 1. A sensor that detects the spectral distribution of light emitted from a light source, and a voltage applied to the light source so that the spectral distribution from the light source becomes a predetermined value based on the detected value from the sensor. An exposure apparatus comprising: a control means for adjusting. 2. Exposure according to claim 1, wherein the control means stores correction data for the voltage applied to the light source corresponding to the spectral distribution, and adjusts the voltage applied to the light source based on this correction data. Device.