JPH0566557A - Color image correction device - Google Patents

Abstract

PURPOSE:To obtain a color-corrected image meeting the printing conditions of printed matter such in-use ink and paper quality. CONSTITUTION:Composite dot signals SDY, SDM, and SDC of Y, M, and C which are ON/OFF binary-coded signals are supplied to applied voltage generation parts 3y, 3M, and 3c. The applied voltage generation parts 3y, 3M, and 3c generate voltage values corresponding to the printing conditions according to the ON/OFF states of the composite dot signals. Their voltages are applied to acousto-optic modulators (AOM) 5Y, 5M, and 5c to adjust the quantities of light beams passing through the AOMs 5y, 5M, and 5c, thereby controlling the coloring density of dots printed on a photosensitive material F.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is directly applicable to image data.
The present invention relates to a color image proofing apparatus for printing a halftone image on a photosensitive material to obtain a color proofing image.

[0002]

2. Description of the Related Art Recently, in color proofing in the printing process,
Image data of yellow (Y), magenta (M), cyan (C), and ink (K) obtained by color-separating a color original is converted into halftone dot signals, and red ( ON / OF each light beam of R), green (G), and blue (B)
A color image proofing device has been used which is F-modulated and directly reproduces a halftone image on a light-sensitive material such as a silver salt color light-sensitive material. According to such a color image proofing apparatus, the finished state of printing can be immediately confirmed by the developed photosensitive material, so that color proofing can be easily performed as compared with the case where a proof plate is prepared.

[0003]

However, the conventional color image proofing device has the following problems. Each of the R, G, and B light beams that expose the photosensitive material is usually modulated by applying a corresponding halftone dot signal to an acousto-optic modulator (AOM). This halftone dot signal is ON / O
Since it is the binary information of the FF, the voltage applied to the AOM is also binary, for example, 5 V when ON and 0 V when OFF. Since the amount of light that the light beam transmits through the AOM depends on the voltage applied to the AOM, the amount of light transmitted through the AOM inevitably becomes a binary amount of light according to ON / OFF. Therefore, the color density of the light-sensitive material determined by the amount of irradiation light is also fixed according to ON / OFF of the dot signal.

On the other hand, the quality of ink and paper actually used in the printing process varies, and thus the finish of printed matter varies depending on the ink and paper quality used. In spite of such circumstances, the conventional color image proofing apparatus fixes the color density based on the average ink or paper quality, so that the same halftone dot image is printed on the photosensitive material. However, a difference in density may occur between the printed matter and the actual printed matter.

Therefore, it is conceivable to make the area of the halftone dots formed on the photosensitive material different from that of the actual printed matter so that no density difference occurs between the calibration output and the printed matter. When compared with printed matter of the same density, the different dot areas give rise to the different problem of giving the viewer a different impression.

Since the main purpose of the proofreading is to faithfully reflect the printing result, it is inconvenient for the image proofing apparatus that the density and the halftone dot area are different from the actual printed matter. Further, according to the conventional device, the clear portion (paper quality portion to which ink is not attached) is AO if it is a negative photosensitive material.
The photosensitive material is uniquely brought into a non-exposed (or exposed) state by completely turning off M or, in the case of a positive photosensitive material, turning on AOM completely.
In other words, it is not possible to adjust the density of the missing part of the calibration output, so it often differs from the actual print quality,
This is also a major factor in giving a proofreading impression that is different from the actual printed matter. Regarding spot color printing, because the conventional device fixes the color density of the light-sensitive material, it is not possible to reproduce the spot color in the halftone dot state, and therefore the spot color printing cannot be calibrated with the conventional device. It was

The present invention has been made in view of the above circumstances, and provides a color image proofing apparatus capable of obtaining a color proofing image suitable for a condition (density) of a printed matter such as ink used and paper quality. The purpose is to do.

[0008]

The present invention has the following constitution in order to achieve such an object. That is, the present invention is a color image proofing apparatus for directly printing a halftone image on a color photosensitive material from a color image data of an original to obtain an image for color proof, and acousto-optical modulation is performed according to a density value of a required area of the original. By adjusting the voltage value applied to the acousto-optic modulator and / or O-state of the acousto-optic modulator.
The transmitted light amount of the printing light beam in the FF state is controlled, and the halftone image is printed on the photosensitive material by the light beam whose transmitted light amount is controlled, thereby controlling the color density of each halftone dot on the photosensitive material. To do.

[0009]

The operation of the present invention is as follows. That is,
By appropriately setting the voltage value applied to the acousto-optic modulator according to the density value of the required area of the document, the amount of light transmitted through the acousto-optic modulator is controlled. By changing the amount of transmitted light of the printing light beam, it is possible to change the density of the halftone dots formed on the photosensitive material even if the halftone dots have the same size. An image for calibration is obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Before explaining the concrete embodiment of the apparatus, the principle of the apparatus of the present invention will be explained with reference to FIG. Figure 1 shows A
The relationship between the applied voltage to the OM, the transmittance of the AOM, the amount of transmitted light of the AOM, and the color density of the photosensitive material is shown. In particular, the amount of transmitted light and the color density are known as γ characteristics of the photosensitive material. It is a thing.

As is apparent from FIG. 1, since the amount of transmitted R, G, B light passing through the AOM is determined by the voltage applied to the AOM, by appropriately setting the ON voltage and the OFF voltage of the AOM, the network The concentration inside and outside the point can be controlled. For example, when it is desired to set the density of the clear area on the photosensitive material to D ₁ and the solid density (density of the area where the halftone dot area is 100%) to D ₂ , the ON voltage applied to the AOM is V ₁ and the OF OF applied.
The F voltage should be set to V ₂ . If a characteristic diagram as shown in FIG. 1 is created for each color of Y, M and C, the relationship between the AOM applied voltage and each color density of the photosensitive material can be understood, and R, G and B can be reproduced to reproduce a desired color. It is possible to know the applied voltage to be set in each AOM corresponding to. In addition, in order to change the color density of the light-sensitive material according to the AOM applied voltage, it is preferable to use the light-sensitive material having a smooth γ characteristic.

<First Embodiment Device> A schematic configuration of the first embodiment device will be described below with reference to FIG. This device
This is an apparatus capable of controlling the density of halftone dots and the density of clear dots in a normal halftone dot image (pattern). Y obtained by reading an original with a color scanner (not shown),
The respective image data of M, C and K are converted into halftone dot signals D _Y , D _M , D _C and D _k by the dot generator 1 and then given to the signal synthesizing circuit 2.

The signal synthesizing circuit 2 has the following role. That is, the color light-sensitive material F is composed of B, G, R
It has the property that each of the complementary colors Y, M, and C develops color when it is exposed to light of each of the three wavelength components, and the part where all three colors of Y, M, and C develop color is black. appear. On the other hand, the halftone dot signals D _Y , D _M , D _C , D
_{Since k} is composed of four colors Y, M, C, K,
In order to directly record a color image on the color light-sensitive material F based on these, it is necessary to combine the halftone dots of black (K) color with the halftone dots of three colors Y, M and C. The signal synthesizing circuit 2 is provided for such a purpose. Each of the Y, M, and C plane halftone dot signals D _Y , D _M , and D _C is converted into the K plane halftone dot signal D _k . It is composed of a logic circuit for synthesizing. A specific configuration of the signal synthesizing circuit 2 is disclosed in, for example, JP-A-64-80.
It is disclosed in Japanese Patent No. 192.

The combined halftone dot signal S obtained by the signal combining circuit 2
_DY , S _DM and S _DC are applied to the applied voltage generators 3 _Y , 3 _M and 3 _C , respectively. Applied voltage generator 3 _Y , 3 _M , 3 _C
Is for converting the combined halftone dot signals S _DY , S _DM and S _DC which are ON / OFF binarized signals into voltage values according to the conditions of the printed matter. Applied voltage generator 3 _Y , 3 _M ,
Each 3 _C has a similar structure. Hereinafter, examples of these configurations are shown in (a) to (c) of FIG.

Applied voltage generator 3 shown in FIG. 3 (a).
Includes a switch 3a that is switched by the ON / OFF of the composite halftone dot signal S _D, while synthetic halftone dot signal S _D to the terminal T ₁ of the switch 3a is set voltages applied at the time of ON, the other terminal T _{In 2} is set the applied voltage when the composite halftone dot signal S _D is OFF. Each applied voltage can be appropriately adjusted by an operator using variable resistors VR1 and VR2 according to printing conditions.

Applied voltage generator 3 shown in FIG. 3B.
Is the terminal group T _1, T _2, ..., the voltage value V ₁ which is different each T _n, V _2, ..., a multiplexer 3 V _n is set
b and a controller 3c for controlling this. The controller 3c operates on the basis of a setting signal from an operation panel (not shown) operated by an operator, and the terminal group T ₁ ,
The multiplexer 3b is controlled so as to select, from T ₂ , ..., T _n , two terminals suitable for the printing conditions in accordance with ON / OFF of the composite halftone dot signal S _D.

Applied voltage generator 3 shown in FIG. 3 (c).
ON / OFF of the composite halftone dot signal S _D based on the setting signal from the outside,
It includes a controller 3d that outputs in response to OFF, and a D / A converter 3e that converts the digital data output from the controller 3d into an analog signal. The controller 3d is composed of, for example, a CPU, and is preset so that digital data adapted to the printing condition is output according to ON / OFF of the composite halftone dot signal S _D.

Returning to FIG. 2, the applied voltage generator 3 _Y ,
The applied voltage values output from 3 _M and 3 _C are passed through AOM drivers 4 _Y , 4 _M and 4 _C , respectively, to AOM5 _Y ,
Given to 5 _M and 5 _C. B, G, R laser light sources 6
_The respective light beams output from _B , 6 _G and 6 _R are ON / OFF modulated by the corresponding AOMs 5 _Y , 5 _M and 5 _C. At this time, since the ON voltage and the OFF voltage according to the printing conditions are applied to the AOMs 5 _Y , 5 _M , and 5 _C , respectively, the amount of transmitted light is adjusted accordingly. The B, G, and R light beams are not limited to those obtained from the individual light sources as described above, and may be obtained by spectrally splitting a white light beam from a single white light source.

The light beam LB _B transmitted through the AOM5 _Y is the total reflection mirror 7 and the light beam LB _G transmitted through the AOM5 _M.
The dichroic mirror 8, a light beam LB _R dichroic mirror 9 having passed through the AOM5 _C, are reflected on the same optical axis, respectively, irradiates the attached photosensitive material F to the rotary cylinder 11 through an imaging lens 10 To be done.

As described above, according to the apparatus of this embodiment,
B, G, modulating each light beam R AOM5 _Y, 5 _M,
The applied voltage at ON time and the applied voltage at OFF time are applied to 5 _C to control the amount of transmitted light. Therefore, it is not necessary to change the halftone dot area to reproduce the same density as the printed matter. In addition, the amount of transmitted light at the time of OFF is negative for a negative photosensitive material and O for a positive photosensitive material.
By setting the amount of transmitted light at N time appropriately, it is possible to reproduce a clear density equivalent to the paper quality of printed matter.
Color proofing with high fidelity can be performed.

<Second Embodiment Apparatus> This embodiment apparatus is a color image proofing apparatus suitable for color proofing of special color printing. Hereinafter, FIG. 4 will be referred to. The Y, M, C, and K image data obtained from a color scanner or the like are converted into density signals by the density conversion circuit 21. Concentration signal Y ₁ , M ₁ ,
C ₁ is added to the density signal K ₁ by adders 22 _Y , 22 _M and 22 _C , respectively. The density signals Y ₂ , M ₂ , and C ₂ obtained by masking with the density signal K ₁ are converted into voltage signals by the density-voltage conversion circuit 23. The voltage signals Y ₃ , M ₃ , and C ₃ are given to the spot color control circuit 24 and converted into voltage values corresponding to the spot colors. The spot color control circuit 24 is composed of, for example, a CPU, and is preset so as to convert the voltage signals Y ₃ , M ₃ , C ₃ output from the density-voltage conversion circuit 23 into voltage values suitable for the spot color density. There is.

If the Y, M, C, and K image data provided from the color scanner or the like are already spot color data, the spot color control circuit 24 may be omitted. However, when the spot color cannot be faithfully reproduced by the image data of the given spot color, for example, when the spot color of the image sample and the spot color expressed by the calibration device are slightly different, the spot color control circuit 24 is used. Then, by finely adjusting the density ratios of Y, M, and C, it is possible to approximate the spot color of the image sample.

The special color voltage signals Y ₄ , M ₄ and C ₄ output from the special color control circuit 24 are changed over by the changeover switch 25.
_It is given to one input terminal of each of _Y , 25 _M , and 25 _C. The other input terminals of the changeover switches 25 _Y , 25 _M , and 25 _C are connected to the clear density setters 26 _Y , 26 _M , and 2 respectively.
The Y, M, and C density voltage values of the blank portion set in advance at 6 _C are given.

Each changeover switch 25 _Y , 25 _M , 25
Switching of _C is performed as follows. The Y, M, C, K image data from the above-described color scanner or the like is applied to the changeover switch 29 _D via the OR gate 28. When the image data does not correspond to the blank portion, the changeover switch 29 _D selects the halftone dot% data T _D of the flat dot from the dot% setting unit 30 _T and sends it to the dot generator 1. The dot generator 1 converts the halftone dot data T _D into a halftone dot signal D _S. This halftone dot signal D _S is used as a changeover control signal for the changeover switches 25 _Y , 25 _M and 25 _C. The network% data for each flat screen is preset in the network% setter 30 _T.

When the halftone dot signal D _S is in the ON state, that is, when the halftone dot of the spot color portion (flat halftone) is to be exposed, the changeover switches 25 _Y , 25 _M and 25 _{C are selected.}
Is a special color voltage signal Y ₄ from the special color control circuit 24,
Select M ₄ and C ₄ . On the other hand, when the halftone dot signal D _S is in the OFF state, that is, in the non-exposed portion, the changeover switches 25 _Y , 25 _M and 25 _{C change} the density from the clear density setting devices 26 _Y , 26 _M and 26 _C. Select the voltage signal.

Changeover switch 25 _Y , 25 _M , 25 _C
The voltage signals respectively output from the D / A converter 27
After being converted into analog signals by _Y , 27 _M and 27 _C respectively, AOM driver 4 _Y , 4 _M and 4 _C
Given to 5 _Y , 5 _M and 5 _C. As a result, each AOM5
When drawing a spot color area, each voltage value according to the spot color density is applied to _Y 5, 5 _M , and 5 _C, and when drawing a missing portion, each voltage value according to the drop density is applied. , A special color original can be printed on a photosensitive material with good reproducibility.

<Third Embodiment Apparatus> This embodiment apparatus is a proofreading apparatus for so-called conventional gravure printing, which is a printing method in which the halftone dot area is fixed to a predetermined value and the density is changed according to the halftone dot depth. It is a thing. Hereinafter, FIG. 5 will be referred to. However, in FIG. 5, the portions denoted by the same reference numerals as those in FIG. 2 or FIG. 4 are the same as the constituent portions described in the first and second embodiments, and therefore detailed description thereof will be omitted.

Similar to the second embodiment, the Y, M, C and K image data from the color scanner or the like are given to the changeover switches 29 _Y , 29 _M , 29 _C and 29 _k . These changeover switches are used to switch the mesh% based on the image data.
Net% for conventional gravure from setter 30 _G
Data is selected and transmitted to the dot generator 1. The dot generator 1 converts this halftone dot data to the halftone dot signal D _Y ,
The signals are converted into D _M , D _C , and D _k and given to the signal synthesis circuit 2.
The signal synthesizing circuit 2 generates halftone dot signals D _Y , D for each of Y, M, C plates.
_M and D _C are combined with the K plate halftone dot signal D _k, and the combined halftone dot signal S _{DY of} Y, M and C masked with this halftone dot signal D _k
, S _DM , S _DC are output. This composite halftone dot signal S _DY , S _DM
, S _DC are used as switching control signals for the changeover switches 25 _Y , 25 _M and 25 _C.

When the combined halftone dot signals S _DY , S _DM and S _DC are in the ON state, that is, when the halftone dot of the conventional gravure is to be exposed, the changeover switches 25 _Y , 25 _M and 25 _{C are selected.} Selects the spot color voltage signals Y ₄ , M ₄ , C ₄ from the spot color control circuit 24. on the other hand,
When the combined halftone dot signals S _DY , S _DM and S _DC are in the OFF state, that is, when there is an unexposed portion, the changeover switches 25 _Y , 25 _M and 25 _C are the clear density setting devices 26 _Y and 26.
Select the concentration voltage signal from _M , 26 _C.

That is, in the third embodiment, the conventional gravure as a target has its halftone dot area fixed at a predetermined value, so that each color is based on Y, M, C, K image data. Halftone dots for conventional gravure are formed in existing portions, and the density inside the halftone dots is adjusted by the spot color control circuit 24.

<Fourth Embodiment Apparatus> This embodiment apparatus is a color image proofing apparatus suitable for calibrating a document in which a normal halftone image (picture) and a spot color are mixed. Hereinafter, FIG. 6 will be referred to. In FIG. 6, the parts designated by the same reference numerals as those in FIGS. 2, 4 and 5 are the same as the constituent parts described in the above-described first to third embodiment devices, and therefore detailed description thereof will be omitted here. Omit it.

Similar to the apparatus of the first embodiment, in the applied voltage generators 3 _Y , 3 _M and 3 _C , the combined halftone dot signals of Y, M and C whose voltage values are adjusted according to the density of the halftone dot image. S _DY ,
S _DM and S _DC are obtained, and these signals are given to one input terminal of each of the changeover switches 31 _Y , 31 _M and 31 _C.

Further, as in the second and third embodiments, the changeover switches 25 _Y , 25 _M and 25 _{C are used} to change the clear density of the spot color voltage signals Y ₄ , M ₄ and C ₄ or Y, M and C, respectively. Voltage signals are output, and these voltage signals are applied to the other input terminal of each of the changeover switches 31 _Y , 31 _M , 31 _C.

Changeover switch 25 _Y , 25 _M , 25 _C
The position discriminator 32 controls the switching of the changeover switches 31 _Y , 31 _M , and 31 _C. Less than,
The function of the position discriminator 32 will be specifically described with reference to FIG. 7. In FIG. 7, reference numeral P is a color original, P ₁ is a normal halftone dot picture area, P ₂ is a special color area, and other areas are blank areas. The color original P is set in a color scanner, and the coordinates of the picture area P ₁ and the spot color area P ₂ are read in advance and set in the position discriminator 32. For example, if each of the areas P ₁ and P ₂ is a rectangular area, the pattern area P ₁
Is given by the X and Y coordinates of points a and b, and the spot color area P ₂ is given by the X and Y coordinates of points c and d. Further, the position discriminator 32 is provided with a position signal of the current drawing position from a color scanner (not shown).

When the current drawing position is in the picture area P ₁ , the position discriminator 32 uses the changeover switches 31 _Y , 3
1 _M and 31 _C are set on the side of the applied voltage generators 3 _Y , 3 _M and 3c. As a result, in the applied voltage generators 3 _Y , 3 _M and 3 c, the combined halftone dot signals S _DY , S _DM and S _DC whose voltage values are adjusted according to the density values of the picture area P ₁ are changed over to the changeover switches 31 _Y , Each AOM driver 4 via 31 _M and 31 _C
Given to _Y , 4 _M , and 4 _C.

On the other hand, when the current drawing position is in the spot color portion P ₂ , the position discriminator 32 causes the changeover switches 25 _Y , 2
5 _M and 25 _C are set to the special color control circuit 24 side, and the changeover switches 31 _Y , 31 _M and 31 _C are set to the changeover switches 25 _Y , 25 _M and 25 _C side. As a result, the spot color density voltage signals Y ₄ , M ₄ , and C ₄ are
Changeover switches 25 _Y , 25 _M , 25 _C , D / A converters 27 _Y , 27 _M , 27 _C , and changeover switch 3
1 _Y , 31 _M , 31 _C via each AOM driver 4 _Y ,
Given to 4 _M and 4 _C. When the spot color is exposed in this embodiment, the OR of the second embodiment (FIG. 4) is used.
Gate 28, changeover switch 29 _D , half-tone dot setter 30
_{Although T} and the dot generator 1 are necessary, these are omitted for convenience of illustration.

When the current drawing position is in the blank area, the position discriminator 32 uses the changeover switches 25 _Y , 2
5 _M , 25 _C is a clear concentration setting device 26 _Y , 26 _M , 26 _C
Side switch and changeover switches 31 _Y , 31
Changeover switch between _M and 31 _C 25 _Y , 25 _M and 25 _C
Set to the side. As a result, the Y, M, and C missing density voltage signals are changed to the changeover switches 25 _Y , 25 _M , 25 _C , and D.
It is given to each AOM driver 4 _Y , 4 _M , 4 _C via the / A converters 27 _Y , 27 _M , 27 _C and the changeover switches 31 _Y , 31 _M , 31 _C.

As described above, according to the apparatus of this embodiment, the voltage applied to the AOM is adjusted in accordance with the density values of the picture area, the spot color area, and the clear area, so that the color original is exposed with good reproducibility. Can be baked onto the material.

In the above embodiment, three channels of AOMs are provided in association with the R, G, and B light beams. However, when the photosensitive material is negative, multiple exposure is possible. It is also possible to use one-channel AOM and print each color by serial processing. However, when the photosensitive material is positive, simultaneous exposure is required due to its structure, and therefore it is necessary to install AOMs for three channels.

[0040]

As is apparent from the above description, according to the present invention, the voltage value applied to the acousto-optic modulator is adjusted in accordance with the density value of the required area of the document to adjust the acousto-optic modulator. By controlling the transmitted light amount of the printing light beam in the ON state and / or the OFF state, and printing a halftone image on the photosensitive material with the light beam whose transmitted light amount is controlled, each halftone dot on the photosensitive material Since the color density of the image is controlled, it is possible to obtain a color proof image that faithfully reproduces the pattern or spot color of the color original or the quality of paper without changing the halftone dot shape.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of a color image proofing apparatus according to the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a first embodiment device.

FIG. 3 is a block diagram showing details of an applied voltage generation unit included in the device of the first embodiment.

FIG. 4 is a block diagram showing a schematic configuration of a second embodiment device.

FIG. 5 is a block diagram showing a schematic configuration of a third embodiment device.

FIG. 6 is a block diagram showing a schematic configuration of a fourth embodiment device.

FIG. 7 is a diagram for explaining the function of the position discriminator included in the device of the fourth embodiment.

[Explanation of symbols]

1 ... Dot generator 2 ... Signal synthesizing circuit 3 _Y , 3 _M , 3 c ... Applied voltage generating unit 4 _Y , 4 _M , 4 _C ... AOM driver 5 _Y , 5 _M , 5 _C ... AOM 6 _B , 6 _G , 6 _R ... Laser light source 7 ... Total reflection mirror 8, 9 ... Dichroic mirror 10 ... Imaging lens 11 ... Rotating cylinder 21 ... Density conversion circuit 22 ... Adder 23 ... Density-voltage conversion circuit 24 ... Special color control circuit 25 _Y , 25 _M , 25 _C ... Changeover switch 26 _Y , 26 _M , 26 _C ... Clear density setting device 27 _Y , 27 _M , 27 _C ... D / A converter 29 _D , 29 _Y , 29 _M , 29 _C , 29 _k ... Changeover switch 30 _T , 30 _G ... Halftone dot setting device 31 _Y , 31 _M , 31 _C ... Changeover switch 32 ... Position discriminator F ... Photosensitive material

[Procedure amendment]

[Submission date] October 14, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction content]

Each changeover switch 25 _Y , 25 _M , 2
Switching of 5 _C is performed as follows. The Y, M, C, K image data from the above-described color scanner or the like is given to the changeover switch 29 _D via the OR gate 28. The change-over switch 29 _D is used for the flat net halftone from the halftone net setter 30 _T when the image data does not correspond to the blank portion.
The data T _D is selected and transmitted to the dot generator 1.
The dot generator 1 converts the halftone dot data T _D into a halftone dot signal D _S. This halftone dot signal D _S is used as a switching control signal for the changeover switches 25 _Y , 25 _M and 25 _C. Note that the dot% setter 30 _T, dot percentage data of the tint area your <br/> is preset.

Claims (1)

[Claims] 1. A color image proofing apparatus for directly printing a halftone image on a color photosensitive material from a color image data of an original to obtain an image for color proofing, wherein an acousto-optic modulator is provided in accordance with a density value of a required area of the original. By adjusting the voltage value applied to the photoacoustic optical modulator to control the transmitted light amount of the printing light beam when the acousto-optic modulator is in the ON state and / or the OFF state, and the transmitted light amount controls the transmitted light beam on the photosensitive material. By printing a halftone image on
A color image proofing device characterized by controlling the color density of each halftone dot on a photosensitive material.