JPS63249671A - Imagewise light exposure apparatus - Google Patents

Abstract

PURPOSE:To obtain a reproduced image equipped with sufficient resolving power and good medium contrast, by controlling an electron beam spot performing dot beam emission on a fluorescent surface on the basis of an image signal. CONSTITUTION:In an image signal forming part 4, the image Sp formed in accordance with the image on a manuscript 2 is supplied to a beam control circuit part 6. The control circuit part 6 generates beam control voltage signals Sg1, Sg2 to supply the same to the electron gun structure at the neck part 12 of a cathode ray tube 8 and the display of an image due to dot beam emission is performed on a screen panel part 10 by the electron beam scanning a fluorescent surface 11. At this time, each dot beam emitting part in the panel part 10 comes to have almost constant brightness such that the diameter thereof is like each of Pa, Pb, Pc corresponding to the level of the image signal Sp. Therefore, in a photosensitive sheet 20, the non-exposure part in each image unit corresponds to each of the beam non-emitting parts W1, W2, W3 in the panel part 10. That is, the medium contrast corresponding to the level of the image signal Sp and sufficient resolving power are provided.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Field of industrial application B. Overview of the invention C. Prior art D. Problems to be solved by the invention E. Means for solving the problems F. ) Specific configuration example of the G-2 electron gun structure and beam control circuit section (
(Fig. 1, Fig. 4) G-3 Exposure state in photosensitive sheet (Fig. 5) G-4 Application to other photosensitive sheets H Effect of the invention A Industrial application field The present invention relates to an apparatus for exposing a sheet-like photosensitive material, which has a surface in which a large number of microcapsules containing a photosensitizer and a dye or a dye precursor, which are hardened in response to light, are dispersed, using image light.

B. Summary of the Invention The present invention provides a sheet-like photosensitive material having a surface in which a large number of microcapsules containing a photosensitizer that cures in response to light in a specific wavelength range and a predetermined dye or dye precursor are dispersed. On the other hand, in a device that exposes a sheet of photosensitive material using image light.

The exposure light source has a screen panel section with a fluorescent surface formed on its inner surface, and is equipped with a cathode ray tube with a built-in electron gun structure, and scans the fluorescent surface with an electron beam emitted from the electron gun structure to generate fluorescent In addition to emitting dots on the light surface, the brightness and size of the electron beam spot on the fluorescent surface that emit dots is controlled based on the supplied video signal, and an image is displayed on the screen panel by dots. By using an image display section to project the image displayed on the screen panel section of the cathode ray tube onto the photosensitive material and exposing the photosensitive material, the exposure of the photosensitive material according to the image can be made relatively simple. Based on a simple configuration, it is possible to reproduce images with sufficient resolution and good halftones during development.

C. Conventional technology A photosensitive sheet consisting of a large number of microcapsules containing a dye precursor and a photosensitizer that is cured by a photopolymerization reaction caused by light in a relatively short wavelength range is dispersed on the surface of a sheet-like substrate. , the dispersed microcapsules are selectively cured by irradiation with light in a predetermined wavelength range, and then reacts with the dye precursor contained in the microcapsules of the photosensitive sheet to form a compound according to the dye precursor. Developing sheets on which a layer of color-developing substance is formed are overlapped and pressed together.
A method of forming an image by crushing microcapsules containing an uncured photosensitizer to develop a color corresponding to the dye precursor contained in the crushed microcapsules by the color developing substance of the developing sheet. has been proposed, for example, as described in Japanese Unexamined Patent Publication No. 59-30537.

In order to obtain a copy image of a document using such an image forming method, for example, a photosensitizer that hardens upon exposure to light in a specific wavelength range, and a photosensitive agent that reacts with a color developing substance of a developer sheet to form a predetermined color therein are used. A photosensitive sheet is prepared in which a large number of microcapsules containing a dye or a dye precursor for color development are dispersed. and,
A positive film is prepared from the original to be copied, and the photosensitive sheet is exposed to light that causes curing of the photosensitizer through the positive film, thereby causing the developer material of the developer sheet in the photosensitive sheet to be exposed to light. Curing occurs in response to the positive film inside the microcapsule containing a dye or dye precursor that produces a predetermined color.

Thereafter, a developing sheet provided with a layer of a color developer is superimposed and pressed onto the photosensitive sheet in which the inside of the microcapsules has been selectively hardened, and the microcapsules inside the photosensitive sheet are cured. The capsule is crushed □. As a result, colored areas of a predetermined color are formed in the color developer layer provided on the developer sheet at positions corresponding to the crushed microcapsules, and a copied image corresponding to the original is obtained. become.

In the photosensitive sheet as described above, the photosensitizer contained in the microcapsules is selectively cured depending on whether it is sensitive to light in a specific wavelength range, and as a result, the color developer layer of the developing sheet It is determined whether or not a colored portion will be formed.

That is, when the amount of exposure during exposure reaches a predetermined value,
It is said that the developing sheet has an exposure characteristic in which the color density changes rapidly from low to high in the color developing area of the developing sheet.

Therefore, it is difficult to finely adjust the intensity of light during exposure to obtain an intermediate tone in the color developer layer of the developing sheet.

Therefore, it is assumed that the image to be copied is divided into small image units composed of multiple pixels, and that the brightness and darkness are obtained by changing the number of pixels that should emit light in each image unit, and the photosensitive sheet is In exposure-1&I, the photosensitive agent is irradiated with light that causes selective hardening of the inside of the microcapsules, and as a result, development An image unit consisting of a plurality of pixels corresponding to the image unit of the image to be copied is formed on the color developer layer of the sheet, and by changing the number of color developing pixels in each image unit, a change in color density can be obtained. It is envisaged that none, thereby reproducing the intermediate tones based on the image to be reproduced on the developer sheet.

D. Problems to be Solved by the Invention However, as described above, when changing the coloring density by changing the number of coloring pixels in each image unit on the developing sheet, the photosensitive sheet is When exposing an image to light that causes curing of the photosensitizer, an image signal corresponding to the image to be copied is obtained and a predetermined signal is applied to it. After processing, image light corresponding to the image signal is generated, but extremely complex circuits are required to process the image signal, and it is difficult to process the image signal. There is a problem that real-time processing is not possible. Furthermore, although exposure devices that generate image light according to image signals that have undergone predetermined processing are required to have resolution at the pixel level, There is an inconvenience that the resolution of the reproduced image is at the level of the image unit.

In view of these points, the present invention provides a method in which a large number of microcapsules containing a photosensitizer and a dye or a dye precursor that harden upon exposure to light in a predetermined wavelength range are dispersed. A sheet-like photosensitive material having a surface can be exposed to light in a relatively compact configuration, and the image reproduced during development can have sufficient resolution and good halftones. An object of the present invention is to provide an image light exposure device that is capable of achieving the following characteristics.

E. Means for Solving the Problems In order to achieve the above-mentioned object, the image light exposure apparatus according to the present invention uses a photosensitizer that cures in response to light in a predetermined wavelength range and a dye or a dye precursor. It has a support part that supports a photosensitive material made of a large number of built-in microcapsules dispersed on the surface of a sheet-like base, and a screen panel part with a fluorescent surface formed on the inner surface, and a built-in electron gun structure. an image display section which is equipped with a cathode ray tube and which scans a fluorescent surface with an electron beam emitted from an electron gun assembly to emit dots on the fluorescent surface; and an image displayed on a screen panel section of the cathode ray tube in the image display section. an image projection unit that exposes the photosensitive material by projecting it onto the photosensitive material; The luminance and size of the spots are controlled, and thereby an image is displayed on the screen panel by dot light emission.

F Effect In the image light exposure apparatus according to the present invention configured as described above, a video signal corresponding to a predetermined image is supplied to the image display section, and the cathode ray tube provided therein operates based on the video signal. An image is generated when a video signal is applied to a screen panel section on which a fluorescent surface is formed, which is scanned by an electron beam emitted from the electron gun assembly of a cathode ray tube.
It is displayed as an image obtained by emitting dots on the fluorescent surface. In this case, the image display by dot light emission on the screen panel section is performed by controlling the brightness and size of the electron beam spot forming the dot light emission on the fluorescent surface based on the video signal. The image displayed on the screen panel section of the cathode ray tube is projected onto the photosensitive material by the image projection section, and the resulting image is directly projected onto the photosensitive material by causing the fluorescent surface to emit dots. exposure is performed.

The brightness and size of the electron beam spot that emits dots on the fluorescent surface are controlled based on the video signal.For example, the higher the level of the video signal, the larger the size of the electron beam spot. At the same time, the brightness is kept approximately constant, so that the level of the video signal is increased even though the photosensitive material is constantly exposed to light with a constant intensity. , the area of the unexposed portion within each unit section is kept small. As a result, the photosensitive material can be exposed to light using a relatively simple configuration, and a reproduced image with sufficient resolution and good halftones can be obtained during development.

G Example G-1 Overall Configuration (FIGS. 2 and 3) FIG. 2 schematically shows an example of an image light exposure apparatus according to the present invention.

In this example, the original 2 is placed on the photosensitive sheet 20.
Exposure is performed according to the image above. The photosensitive sheet 20 is
As shown enlarged in FIG. 3, a sheet-like base 20a
A large number of microcapsules Cp containing a photosensitizer that hardens upon exposure to light in a specific wavelength range and a dye or a dye precursor, such as a leuco dye, are dispersed on the surface of the microcapsule Cp. It has been arranged as follows.

The leuco dye contained in the microcapsules Cp reacts with the color developing material layer of the developing sheet used in connection with the photosensitive sheet 20 to change the color developing material layer of the developing sheet to a predetermined color.
For example, it is said to have the property of producing a black color. Therefore, when the photosensitive sheet 20 after the exposure process is applied to a developing sheet, for example, the photosensitive sheet 20 is overlapped and pressed on the color developing material layer of the developing sheet,
Microcapsules Cp that did not undergo curing due to exposure in the unexposed areas of the photosensitive sheet 20
is crushed, and the leuco dye contained in the microcapsules Cp reacts with the color developer layer of the developer sheet.
The area corresponding to the area that was not exposed at 0 will appear black.

The image on the original 2 is captured by an imaging means included in the video signal forming section 4, and the image on the original 2 is captured by the imaging means included in the video signal forming section 4.
A video signal Sp formed according to the above image is obtained,
It is supplied to the beam control circuit section 6 in the image display section 5.

The image display section 5 includes a cathode ray tube 8 to which a beam control circuit section 6 is connected. The cathode ray tube 8 is provided with a fluorescent surface 11 on the inner surface of its screen panel portion 10. This fluorescent surface 11 is emitted from an electron gun assembly built in the neck portion 12, and the fluorescent surface 11 is emitted from the outer surface of the cathode ray tube 8. Scanning is performed by an electron beam deflected by beam deflection means 14 disposed on the side. The beam control circuit section 6 receives the video signal Sp from the video signal forming section 4, generates beam control voltage signals Sg+ and Sgz based on the video signal Sp, and incorporates them into the neck section 12 of the cathode ray tube 8. The electron beam emitted from the electron gun assembly and scanning the fluorescent surface 11 is controlled so as to emit dots on the fluorescent surface 11, and the electron beam is controlled in accordance with the video signal Sp. The brightness and size of the electron beam spot on the fluorescent surface 11 that emits dot light are controlled, thereby displaying an image on the screen panel section 10 by dot light emission.

In this way, the video signal Sp displayed on the screen panel section 10 of the cathode ray tube 8 in the image display section 5
An image based on the support member 2 is formed by an image projection unit 52 including a lens means 50 and a shutter 51.
The image light is projected onto the photosensitive sheet 20 supported by the video signal Sp 2, thereby exposing the photosensitive sheet 20 to image light from the image based on the video signal Sp.

Specific configuration example of G-2 electron gun structure and beam control circuit section (
(FIGS. 1 and 4) FIG. 1 shows a specific example of the structure of an electron gun assembly built into the neck portion 12 of the cathode ray tube 8, and a specific example of the structure of the beam control circuit section 6 connected thereto.

In the example shown in FIG. 1, an electron gun assembly 24 built into the neck portion 12 of the cathode ray tube 8 is supported by a pair of beading glasses 25 and includes first grid electrodes G1. Second grid electrode G2. Third grid electrode G3. Fourth grid electrode G4 and fifth grid electrode G
It has an electrode group consisting of 5. 1st grid electrode G
The second grid electrode G2 and the third grid electrode G3 are respectively provided with through holes Or, Ot and 0 through which the electron beam passes, and the fourth grid electrode G4 and the fifth grid electrode G5 are It is formed on a cylinder. 1st
The grid electrode G1 is formed into a cup shape, and a cathode assembly 26 including a heater 27 and a cathode 28 is disposed inside the grid electrode G1 and supported by a ceramic support member 29.

Based on this configuration, the heater drive voltage vh is supplied to the heater 27 of the cathode assembly 26, and the cathode 28
is grounded, while the second grid electrode 02. The grid voltage Vg! is applied to the third grid electrode G3 and the fifth grid electrode G5, respectively. , Vg.

and Vgs are applied, and the first grid electrode Gl
Beam control voltage signals Sg and Sgt obtained from the beam control circuit section 6 are supplied to the fourth grid electrode G4, respectively. Then, the heater 27 has a heater drive voltage vh
The cathode 28 receives the supply of heat and generates heat, thereby causing the cathode 28 to
The electrons emitted from the cathode 28 emit electrons in response to the beam control voltage signal Sg+ supplied to the first grid electrode G1. The electron beam is converted into an electron beam by the cathode lens forming part including the first grid electrode G1 and the second grid electrode G2, and passes through the through holes O1 and Ot formed in the first grid electrode Gl and the second grid electrode G2 to the third grid electrode 03. sent to the side. Through hole 0. The electron beam passing through the grid electrodes G2 and G3 is focused by the prefocus section formed by the second grid electrode G2 and the third grid electrode G3, and then further focused by the third grid electrode G3. The electron beam is focused by the main focus section formed by the fourth grid electrode G4 and the fifth grid electrode G5, and is emitted to the outside of the electron gun assembly 24 as a focused electron beam.

The electron beam emitted from the electron gun assembly 24 passes through the horizontal and vertical deflection magnetic fields formed by the beam deflection means 14, receives horizontal and vertical deflection, and is directed to the screen panel section 1.
0, and performs horizontal scanning and vertical scanning on the fluorescent surface 11.

On the other hand, in the beam control circuit section 6, the video signal Sp sent out from the video signal forming section 4 is supplied to the control signal forming section 32 via the input terminal 30. Control signal forming section 3
2 forms a control signal C6 and a control signal C2 based on the video signal Sp.

In addition, a voltage generating section 34 that generates the voltage Vgs for the first grid and a voltage generating section 36 that generates the voltage Vga for the fourth grid are provided, and the voltage Vg+ for the first grid from the voltage generating section 34 is adjusted. The voltage Vg4 for the fourth grid from the voltage generating section 36 is supplied to the voltage generating section 38.
is supplied to the voltage regulator 40. And voltage adjustment section 3
8 and 40, the video signal S is sent from the control signal forming section 32.
The control signals CI and C2 obtained based on p are also, respectively,
Supplied.

The voltage regulator 38 converts the first grid voltage Vg+ from the voltage generator 34 into a control signal C from the control signal generator 32.
A beam control voltage signal Sg+ is modulated according to I, and is applied to the first grid electrode G1 in the electron gun assembly 24.
supply to. The beam control voltage signal SgI causes the cathode 28 in the electron gun assembly 24 to emit electrons intermittently at a predetermined period, and as a result, an electron beam is emitted from the electron gun assembly 24 and scans the fluorescent surface 11. , fluorescent surface 1
1, and the level thereof is assumed to change in accordance with a change in the level of the video signal Sp. This beam control voltage signal Sg+ has a negative level Lg+ with respect to the cathode voltage level (zero level), and this level Lgl is, for example, the level Lsp of the video signal Sp, as shown in FIG. 4A. The relationship is set such that as the voltage becomes larger, the negative value thereof becomes smaller, that is, it approaches the cathode voltage level. .

In this way, the level Lg+ of the beam control voltage signal Sg+
As the level Lsp of the video signal Sp increases, its negative value decreases, so that the beam current of the electron beam emitted from the electron gun assembly 24 and scanning the fluorescent surface 11 increases. , the higher the level Lsp of the video signal Sp, the higher the level Lsp, and assuming that the size of the electron beam spot formed on the fluorescent surface 11 is constant, the brightness of the electron beam spot is: The higher the level Lsp of the video signal Sp becomes, the higher the level Lsp becomes.

Further, the voltage adjusting section 40 converts the fourth grid voltage Vga from the voltage generating section 36 into the control signal C! from the control signal forming section 32! The beam control voltage signal Sgt is modulated according to the beam control voltage signal Sgt, and is supplied to the fourth grid electrode G4 in the electron gun assembly 24 as a focus voltage. The beam control voltage signal Sgz has a relatively high positive level Lgt with respect to the cathode voltage level (zero level), and this level L
It is assumed that g2 changes according to a change in the level of the video signal Sp. The level L of such beam control voltage signal Sg2
For example, as shown in FIG. 4B, gz is the video signal S
The relationship is set such that as the level Lsp of p increases, its positive value increases.

In this way, the level Lgz of the beam control voltage signal Sgz
As the level Lsp of the video signal Sp increases, its positive value increases, so that the electron beam emitted from the electron gun assembly 24 and scanning the fluorescent surface 11 can increase the level Lsp of the video signal Sp. The larger the level Lsp is, the larger the diameter becomes.Therefore, the larger the level Lsp of the video signal Sp is, the larger the size of the electron beam spot formed on the fluorescent surface 1 is. It turns out.

As described above, from the voltage regulator 38 to the first grid electrode G
1, the level t of the beam control voltage signal Sg, supplied to
gl and the level Lgz of the beam control voltage signal Sgz supplied from the voltage adjustment unit 40 to the fourth grid electrode G4 are changed in accordance with the change in the level Lsp of the video signal Sp. The diameter of the electron beam that is emitted and scans the fluorescent surface 11 increases as the level Lsp of the video signal Sp increases;
In addition, the beam current increases as the level Lsp of the video signal Sp increases, and as a result, the fluorescent surface 11
The size of the electron beam spot formed in the image signal becomes larger as the level LSp of the video signal Sp becomes larger, and its brightness is kept substantially constant despite changes in size. Then, the screen panel section 10 of the cathode ray tube 8
, an image is displayed according to the video signal Sp by dot light emission on the fluorescent surface 11.

In this way, the image based on the video signal Sp displayed on the screen panel section 10 of the cathode ray tube 8 in the image display section 5 is supported by the support member 22 by the image projection section 52, as shown in FIG. The image is projected onto the photosensitive sheet 20, and the photosensitive sheet 20 is exposed.

G-3 Exposure state in photosensitive sheet (FIG. 5) When exposing the photosensitive sheet 20 to image light from an image based on the video signal Sp, in the screen panel section 10 of the cathode ray tube 8 in the image display section 5. In this case, dot light emission is performed, for example, in the manner shown in FIGS. 5A, B, and C. In each of FIGS. 5A, 5B, and 5C, arrows indicate the horizontal scanning direction of the electron beam scanning the fluorescent surface 11 located on the inner surface side of the screen panel section 10.

In fact, when the level of the video signal Sp is relatively low, the size of the electron beam spot formed on the fluorescent surface 11 is relatively small, so as shown in FIG. 5A, Each dot light emitting section Pa in the screen panel section 1O has a relatively small diameter, and therefore, between the horizontal scanning lines of two adjacent electron beams and between the two adjacent horizontal scanning lines on each horizontal scanning line. The non-light emitting portion W in the unit area formed between the dot light emitting portions Pa has a relatively large area. Furthermore, when the level of the video signal Sp is medium, the size of the electron beam spot formed on the fluorescent surface 11 is medium;
As shown in FIG. 5B, each dot light emitting section Pb in the screen panel section 10 has a medium diameter, and therefore, each dot light emitting section Pb in the screen panel section 10 has a medium diameter. The non-light-emitting portion W2 in the unit region formed between the upper two adjacent dot light-emitting portions Pb has a medium area. Furthermore, when the level of the video signal Sp is relatively high, the size of the electron beam spot formed on the fluorescent surface 11 is relatively large, so that the screen panel Each dot light emitting part Pc in the section 10 has a relatively large diameter, so that two dot light emitting parts adjacent to each other between the horizontal scanning lines of two adjacent electron beams and on each horizontal scanning line have a relatively large diameter. The non-light-emitting portion W in the unit region formed between the portions Pc has a relatively small area.

In such a case, the brightness of the electron beam spot formed on the fluorescent surface 11 is approximately constant regardless of its size, so each of the above-mentioned dot light emitting parts Pa, Pb and Pc is , has a substantially constant brightness. Therefore, in one light-emitting sheet 20 that is exposed based on the dot light-emitting parts Pa, Pb, and Pc in the screen panel section 10 as described above, the unexposed portion in each image unit is It depends on the non-light emitting parts W, , W, and W. That is, when the level of the video signal Sp is relatively low, the non-exposed portion in each image unit of the photosensitive sheet 20 has a relatively small area corresponding to the non-light emitting portion WI shown in FIG. 5A. When the level of the video signal Sp is medium, it has a medium area corresponding to the non-light emitting part W2 shown in FIG. 5B, and when the level of the video signal Sp is relatively high, In some cases, it has a relatively large area corresponding to the non-light-emitting portion W2 shown in FIG. 5C.

The reason why the photosensitive sheet 20 that has undergone such an exposure process is made to act on a developer sheet and the color developer layer of the developer sheet is colored black is because the photosensitive sheet 20 is not exposed to light in the color developer layer of the developer sheet. This will be the area corresponding to the part. Therefore, in each image unit of the color developing material layer of the developing sheet, when the level of the video signal Sp is relatively low, the area of the black colored portion is relatively large.
When the level of the video signal Sp is medium, the area of the black colored portion is medium, and when the level is relatively high, the area of the black colored portion is relatively small. Therefore, the image reproduced on the developing sheet according to the video signal Sp, that is, the copy image of the image on the original 2, is dark in subdivisions where the level of the video signal Sp is relatively low; The density is medium in areas where the level is medium, and it is light in areas where the level of the video signal Sp is relatively high, so that a halftone corresponding to the level of the video signal Sp can be obtained. . In addition, in this way, the resolution of the image reproduced on the developing sheet according to the video signal Sp is made to correspond to the dot light emitting parts Pa, Pb, and Pc in the screen panel part 10. , therefore, it has sufficient resolution.

G-4 Application to other photosensitive sheets It should be noted that the photosensitive sheet 20 may contain, instead of the microcapsules Cp, a photosensitizer that hardens upon exposure to light in a specific wavelength range, and a dye or dye other than the koiko dye. Of course, the above-described example can also be applied to the photosensitive sheet 20 including the microcapsules Cp even in the case where the photosensitive sheet 20 includes the microcapsules containing the precursor.

Effects of the Invention H As is clear from the above explanation, the image light exposure apparatus according to the present invention combines a photosensitizer that hardens upon exposure to light in a specific wavelength range and a predetermined dye or dye precursor. When a sheet-like photosensitive material having a surface in which a large number of microcapsules contained therein are dispersed is exposed in accordance with a predetermined image, an image corresponding to the image is displayed on a screen panel section. A cathode ray tube is used, and the image displayed by the cathode ray tube is used as the exposure light source, and furthermore, the image displayed by the cathode ray tube is such that the unexposed portion within each image unit of the light-sensitive material is the same as each image unit of the original image. The area changes depending on the brightness of the area. Therefore, exposure of a sheet-like photosensitive material according to a predetermined image can be performed using a relatively simple structure that does not require complicated circuits for special video signal processing.
This means that development can be carried out in a state where a reproduced image with sufficient resolution and good halftones can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a specific example of the main part of an example of the image light exposure apparatus according to the present invention, FIG. 2 is a schematic block diagram showing an example of the image light exposure apparatus according to the present invention, and FIG. Figures 4A and B, and 5A, B and C, which are used to explain the photosensitive sheet applied to the example shown in Figure 2, are used to explain the operation of the example shown in Figure 2. FIG. In the figure, 2 is an original, 4 is a video signal forming section, 5 is an image display section, 6 is a beam control circuit section, 8 is a cathode ray tube, 10 is a screen panel section, 11 is a fluorescent surface, 20 is a photosensitive sheet, 22
24 is a support member, 24 is an electron gun assembly, 32 is a control signal forming section, 38 and 40 are voltage adjustment sections, 42 is an image projection section, G1
．． G2. G3°G4 and G5 are the 1st. Second. Third. Fourth
and a fifth grid electrode. 5p B Lsρ Characteristic diagram of the example Fig. 4 Provided diagram Fig. 5

Claims (1)

[Scope of Claims] A photosensitive material comprising a large number of microcapsules containing a photosensitizer and a dye or dye precursor that harden in response to light in a predetermined wavelength range and are dispersed on the surface of a sheet-like substrate. and a screen panel part with a fluorescent surface formed on its inner surface, and a cathode ray tube with a built-in electron gun structure, and the fluorescent surface is illuminated by an electron beam emitted from the electron gun structure. Scanning and emitting dots on the fluorescent surface, and controlling the brightness and size of the electron beam spot on the fluorescent surface that emits dots based on the supplied video signal, An image display unit that displays an image using the dot emission; and an image projection unit that projects the image displayed on the screen panel of the cathode ray tube onto the photosensitive material and exposes the photosensitive material. image light exposure device.