JPS63184735A - Image forming method - Google Patents

Abstract

PURPOSE:To adjust optimum gray balance in each picture element density by correcting the exposure of each color on the basis of the coloring characteristics of each color on a photosensitive material. CONSTITUTION:Color-decomposed color image information forms its image on a CCD sensor 208 through a lens 207 in each color. An image signal in each color read by the CCD sensor 208 is converted into a digital signal by an A/D converter 209 and the deterioration of spatial frequency response due to the lens 207 or the CCD sensor 208 is corrected by an outline emphasizing circuit 210. The exposure of each picture element is determined by a color correcting matrix computing circuit 211. An exposure control circuit 212 controls exposure to a photosensitive material 214 through an exposure generating part 213 on the basis of the exposure determined in each color. Thus, the gray balance can be kept at the optimum level even in any image density.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a color image forming apparatus, and particularly to an image forming method using a digital exposure apparatus.

(Prior art) In recent years, in image forming apparatuses, color-separated color image information is photoelectrically converted by a solid-state sensor such as a COD, and then further converted into a digital signal. Digital exposure apparatuses have been proposed that control the amount of exposure for exposing materials.

For example, the digital exposure apparatus separates a color image by time-sharing color image information using a liquid crystal filter unit that is divided into three color areas on a plane perpendicular to the optical axis. The image signals read by the COD for each color are digitally converted by the A/D converter 9-1, and then
The contour enhancement circuit corrects the deterioration of spatial frequency response due to the imaging lens and COD for each pixel of the CCD, and the color correction matrix is determined by the color correction matrix calculation circuit to determine the exposure amount for each pixel. Furthermore, the exposure control circuit controls the exposure of the photosensitive material in accordance with the exposure amount for each color to form a color image on the photosensitive material.

In this manner, in the digital exposure apparatus, it is easy to adjust the exposure amount for color correction, etc., and it is possible to form a high-quality color image.

(Problem to be Solved by the Invention) However, when the color development characteristics of the three color photosensitive materials are different, it is difficult to obtain an image density with a well-balanced gray even if the same exposure amount is applied to the RGBa color photosensitive materials. I can't. For this reason, when adjusting the color balance of the formed image in the exposure control unit, even if the gray balance of RGBa colors is adjusted to the optimum value at a certain image density, the gray balance of other image sources 1i [in This has the disadvantage that a good color image cannot be obtained because of this.

Therefore, an object of the present invention is to solve the above problem. Even when using color sensitive materials with different coloring characteristics in a digital exposure device, this can be corrected to optimize the gray balance at each image density. The object of the present invention is to provide an image forming method for forming an image of good quality on a photosensitive material.

(Means for Solving the Problems) The above-mentioned object of the present invention is to measure the color development characteristics of each color of a color photosensitive material having spectral sensitivity in the visible region in advance by 1 liter.
This is achieved by an image forming method in which a photosensitive material is exposed by determining and storing lIj and controlling the exposure amount for a desired document density corresponding to image information based on the stored coloring characteristics of each color.

That is, since the exposure amount of each color is corrected based on the color development characteristics of each color of the photosensitive material, it is possible to optimally adjust the gray balance at each image density.

In the present invention, the photosensitive material refers to a material for obtaining a visible image by applying pressure to a latent image generated by imagewise exposure.

In this case, it may include a step of preliminary heat development or wet development before applying pressure.

An example of such a material is a type of material in which a polymerizable compound is imagewise cured by imagewise exposure and then covered with pressure to obtain a visible image, as disclosed in Japanese Patent Application Laid-Open No. 57-1981 filed by the present applicant. The material disclosed in Japanese Patent No. 179836 is mentioned. This material has a synthetic polymer resin wall capsule containing a vinyl compound, a photopolymerization initiator, and a colorant precursor supported on a support.

Alternatively, after containing silver halide and giving imagewise exposure, heat development is performed to develop the silver halide, the polymerizable compound is simultaneously cured in correspondence with this development, and then pressure is applied to form a visible image. Examples of materials that can be obtained include the materials disclosed in Japanese Patent Application No. 121284/1984 or Japanese Patent Application No. 53881/1981 filed by the present applicant. The material disclosed in the above-mentioned Japanese Patent Application No. 121284/1984 is a material that is thermally developed and then transferred to an image-receiving material having an image-receiving layer to obtain an image on the image-receiving material. At least a photosensitive silver halide, a reducing agent, a polymerizable compound, and a color image-forming substance are coated, and at least the polymerizable compound and the color image-forming substance are encapsulated in the same microcapsule. .

Furthermore, the material disclosed in the above-mentioned Japanese Patent Application No. 61-53881 does not require the use of an image-receiving material (an image is obtained on a light-sensitive material, and a color-forming reaction occurs in contact with silver halide, a reducing agent, a polymerizable compound, and a photosensitive material). One of the substances that cause a color reaction and a polymerizable compound are contained in microcapsules, and the other substance that causes a color reaction contains a polymerizable compound. It has a photosensitive layer on the support that exists outside the microcapsules.

Note that the image recording apparatus for carrying out the method of the present invention is one that has a heat development device when using a type of photosensitive material that performs heat development before fixing the image by applying pressure. When using a type that does not perform this process, it means a type that does not have a heat developing device.

(Embodiment) Embodiments of the present invention will be described below.

FIG. 1 is a sectional view of an image recording apparatus for carrying out the method of the present invention. In the figure, a digital exposure device 200 is arranged on the upper part of the housing 1.
The portion containing 00 is separated from other portions by the partition wall 224. An opening 228 is provided in a portion of the digital exposure apparatus 200 through which the optical axis passes.

A photosensitive material cartridge 14 containing a photosensitive material roll 12 wound with a photosensitive and pressure sensitive heat-developable color photosensitive material S (hereinafter referred to as photosensitive material) is removably attached to the side of the housing 1. At the outlet 16 of the photosensitive material S of the photosensitive material cartridge 14, a pair of photosensitive material (take-out rolls 22, 22) housed in the magazine connection dark box 20 is arranged, whereby the photosensitive material wound on the photosensitive material roll 12 is removed. S is pulled out by a certain length at a predetermined time.

When the leading edge of the photosensitive material S has advanced, the photosensitive material extraction rolls 22, 22 move away from each other as shown by phantom lines to facilitate the advancement of the photosensitive material S. A cutter unit 23 for cutting the photosensitive material S and a guide plate 24 are disposed in front of the magazine connection dark box 20 (hereinafter, the term "front" refers to the downstream side in the traveling direction of the photosensitive material, etc.).

In front of the guide plate 24, an exposed photosensitive material support roll 26 and two photosensitive material nip rolls 28, 30 pressed against the exposed photosensitive material support roll 26 are arranged. The photosensitive material S guided by the guide plate 24 is brought into close contact with the exposed photosensitive material support roll 26 by the photosensitive material nip rolls 28.30.
Imagewise exposure is performed by exposure device 200 at a position 32 between 30 and 30 .

A heat developing device 40 that heats and develops the exposed photosensitive material S is arranged in front of the exposed photosensitive material support roll 26 . The heat developing device 40 includes a developing housing 42 having a heat insulating effect, and is disposed within the developing housing 42, and has a diameter of about 120 mm.
An endless belt 50 is supported by a heating roll 44 that is heated to a temperature of The nip roll 52 is pressed into contact with the nip roll 52.

The heat developing device 40 further includes an exposed light-sensitive material support roll 26.
A guide device 54 that guides the photosensitive material S sent from the W onto the heating roll 44 and separates the photosensitive material S from the W heating roll 44 after being heated and developed; It has a vertical guide device 58 for guiding the material to the exit 56, and the exit 56 is provided with a sensor 60 for detecting the tip of the sensitive material.

Immediately below the outlet 56, a pair of pressure rolls 62 and 64 are provided.
A photosensitive material image-receiving paper stacking device comprising a nip roll 66 pressed against the pressure roll 64, and a guide member 68 that guides the image-receiving paper C fed by the pressure roll 64 and the nip roll 66 to the contact portion of the pressure rolls 62 and 64. is placed.

An image-receiving paper supply device 72 is disposed on the side of the photosensitive image-receiving paper stacking device 70 . The image-receiving paper supply device 72 includes a removably attached image-receiving paper supply cassette 74 that protrudes from the housing 1, and an image-receiving paper C in the cassette 74 (
The image receiving paper to be fed out (feeding roll 76 and the image receiving paper C fed out by the feeding roll 76 is pressed into contact with the roll 64
and a guide plate 78 that guides the nip roll 66 to the contact portion. Here, the width of the image-receiving paper C is about 611111 smaller than the width of the photosensitive material S, and in the photosensitive image-receiving paper stacking device 70, the width of the image-receiving paper C is about 611111 smaller than the width of the photosensitive material S.
are superimposed so that they are in the center.

Below the photosensitive image receiving paper stacking device 70, a pair of pressure nip rolls 80, 82 and 710 pressure = tube roll 80 are provided.
．． A transfer device 88 is provided which includes backup rolls 84 and 86 for making the pressure applied to the roller 82 uniform in the axial direction. Pressure nip roll 80.82 is approximately 500F
They are pressed together by a pressure of tP/m.

A photoreceptor paper peeling device 90 is provided below the transfer device 88 . The sensitive image receiving paper peeling device 90 includes a guide member 92, a first feed roll 94, a second feed roll 96, and a first
At the outer edge portion of the feed roll 94, the photosensitive material S
A peeling belt 102 is wound around guide rolls 98, 100 so as to press against the peeling belt 102.

A sensitive material disposal section 104 is provided on one side of the peeling device 90, and a fixing device 106 is provided on the other side. The sensitive material disposal unit 104 includes a guide member 108, a pair of feed rolls 110 and 112, and a disposal unit 114.
The photosensitive material S sent from the peeling device 90 and guided by the guide member 108 is thrown into a waste dump 114 by feeding rolls 110 and 112.

The fixing device 106 includes a guide member 120 and a reflective member 12.
2 ultraviolet irradiation lamps 124 and a pair of feed rolls 1
26 and 128, and is sent from the peeling device 90 and guided by the guide member 120C. The image receiving paper C is irradiated with ultraviolet light for about 5 seconds to effect fixation at °C.

A take-out tray 130 for receiving the image-receiving paper C is attached to the front of the fixing device fi 106 so as to protrude from the housing 1.

FIG. 2 is a schematic block diagram of the digital exposure apparatus 200.

The illumination device 202 provided below the document support glass 201 with the document facing downwards moves together with the mirror 203, and the mirrors 204 and 205 move in the same direction at the speed H of the illumination device 202 and the mirror 203. to allow the projection light beam of the original to reach the liquid crystal filter unit 206. The liquid crystal filter unit is divided into three color areas on a plane perpendicular to the optical axis of color image information, and in time division, only one of the three colors becomes transparent, while the other two colors become transparent. is in a non-transparent state, so the color image information is separated into three colors. The color-separated color image information is imaged on a CCD sensor 208 by a lens 207 for each color.

The image signal for each color read by the CCD sensor 208 is converted into a digital signal by the A/D converter 209, and then the contour enhancement circuit 210 corrects the spatial frequency response deterioration caused by the lens 207 and the CCD sensor 208. . Furthermore, the color correction matrix calculation circuit 211 determines the exposure amount for each pixel.

Based on the exposure amount determined for each color, the exposure control circuit 212 controls the exposure of the photosensitive material 214 via the exposure light generating section 213.

The exposure control circuit 212 includes an input means for inputting the color development characteristics of the exposure amount and density for each photosensitive material of each color, and an LUT (Lookt) for outputting the exposure amount corresponding to the density for each color.
yp Tablg).

The coloring characteristics of the photosensitive material for each color, for example,
For example, 4 points P for each color as shown in the figure. ~P3 is measured as coordinate data approximated by a broken line, and is written on the photosensitive material packaging. The coordinate data is then input to the exposure control circuit 212 for each color using a manual means such as a numeric keypad.
Stored in LUT. Here, the coordinate data measured in advance may be recorded by electrical and magnetic means such as an IC card or a magnetic stripe and input into the exposure control circuit.

In the LUT, each color is reproduced based on the coordinate data of each color inputted in advance (
Figure 4). Then, the exposure control circuit 212 determines the appropriate exposure amount for the desired color density for each of the three colors based on the reproduced coloring characteristics, and corrects the exposure amount determined by the color correction matrix calculation circuit 211.

Here, in this embodiment, an image forming apparatus as a color copying machine has been described, but the present invention is not limited to this, and as long as it has a digital exposure device, for example, a color image forming apparatus on a CRT can be formed. It can also be used in printers such as color hard copiers that copy images onto receiving paper.

Furthermore, the number of coordinate data for measuring the coloring characteristics approximated by a broken line for each color is not limited to four, and the number of coordinate data may be increased to obtain a finer approximation (approximation).

(Effects of the Invention) According to the present invention, even when using color photosensitive materials with different color development characteristics for each color or when there are manufacturing irregularities, the exposure amount can be corrected for each color to determine the image density. , gray balance can be optimized at any image density.

Therefore, a formed image with good image quality can be easily obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an image recording device for carrying out the method of the present invention, and FIG. 2 is a schematic block diagram of a digital exposure device. @Figure 3 is a color development characteristic diagram showing an example of a broken line approximation of the color development characteristics of a photosensitive material, and Figure 4 is the RG reproduced in the exposure control circuit.
It is a broken line approximate color development characteristic diagram of BS color. (Symbols in the figure) S...Photosensitive material C...Receiver paper 1...Housing 12...Sensitive material roll 14...Sensitive material cartridge 16...Outlet 20...Magazine connection dark box 22.
...Sensitive material (extrusion roll 23...Cutter unit 24...Guide plate 26...Exposed sensitive material support roll 2
8.30...Sensitive material nip roll 32...Exposure position 40...Heat developing device 42...Developing) Uzing 44...Heating roll 46,47.48.49...
Belt support roll 50...Belt 52...Nip roll 54...Guide device 56...Outlet 58
... Vertical guide device 60 ... Sensor 62.64
... Pressure roll 66 ... Nip roll 68 ...
・Guide member 70...Sensitive material image-receiving paper stacking device 7
2...Image receiving paper 4. Connection supply device 74...Image receiving paper supply cassette 76...Image receiving paper (extrusion roll 78...Guide plate 80°82
... Pressure nip roll 84.86 ... / Tsukatsuzo roll 88 ... Transfer device 90 ... Peeling device 92 ... Guide member 94 ... First feed roll 9
6...Second feed roll 98,100...Guide roll 102...Peeling belt 104...Sensitive material disposal section 1
06... Fixing device 108... Guide member 110
゜112...Feed roll 114...Disposal number 120...Guide member 122...Reflection member 12
4...Ramp 126.128...Feed roll 1
30... Ejection tray 200... Digital exposure device 201... Document support glass 202... Illumination device 203, 204, 205... Mirror 206... Liquid crystal filter unit 207... Lens 208...
・CCD sensor 209...A/D controller 2
10... Contour emphasis circuit 211... Color correction matrix calculation circuit 212... - Exposure control circuit 213...
Exposure light generating section 214...Photosensitive material (3 others), Do

Claims (3)

[Claims] (1) The coloring characteristics of each color of a color photosensitive material having spectral sensitivity at least in the visible region are measured and stored in advance, and the exposure amount for the desired document density corresponding to the image information is determined based on the stored coloring characteristics of each color. An image forming method characterized by controlling exposure of a photosensitive material. (2) The image forming method according to claim 1, wherein the coloring characteristic storage means is an electric storage means such as an IC card. (3) The image forming method according to claim 1, wherein the coloring characteristic storage means is a magnetic storage means such as a magnetic stripe.