JPH03289862A - Picture processing unit - Google Patents

Abstract

PURPOSE:To always record a picture having a prescribed contrast into a spatial optical modulation element by radiating a light to an original, writing a picture onto a picture write plane of the spatial optical modulation element analogically and detecting an average lightness of the written picture so as to regulate an input sensitivity or regulate the intensity of light. CONSTITUTION:At least one of light sources 11a, 11b, 11c is lighted to form image of picture written in a spatial optical modulation element 10 onto a photodetector 20a to measure the lightness of the picture. Moreover, a contrast control system 20 is provided with a power supply 20c able to control a voltage applied between electrodes of the spatial optical modulation element 10 in response to a detection output of the photodetector 20a. When a voltage applied between the electrodes of the spatial optical modulation element 10 rises, the sensitivity with respect to an incident light is increased and when the voltage is decreased, the sensitivity with respect to the incident light is decreased. Thus, the dynamic range of the spatial optical modulation element 10 is controlled by the applied voltage and the optimum dynamic range is obtained at all times with respect to the reflecting image of the original 18 made incident in the spatial optical modulation element 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing device using a spatial light modulation element.

[Prior Art] Color copying machines are known as devices for creating, editing, and copying full-color images.

Color copying machines generally come in two types: analog type and digital type, and each type has its advantages and disadvantages.

Analog color copying machines create color copies by exposing and developing optical images, making it difficult to perform image processing such as color correction and gradation processing. On the other hand, digital color copying machines use an image scanner to convert the original image into a digital signal, and then use a printer to create a color copy according to this digital signal, so color correction, gradation processing, etc. Image processing etc. can be easily performed.

Comparing the color copies produced, analog color copying machines produce smoother image quality (resolution of 8
00 DPI), but color masking (separation of black and chromatic colors) is not easy and color reproducibility is not very good. Specifically, black line drawings are colored. on the other hand,
Digital color copying machines facilitate color masking and have excellent color reproducibility, but it is difficult to achieve high definition. Increasing the number of pixels to read with higher resolution increases the amount of data, which requires a high-speed processor and large-capacity memory, which is a significant disadvantage in terms of cost compared to analog methods.

From this point of view, analog color copiers are advantageous when performing large-volume copy processing, while digital color copiers are useful for creating design manuscripts where color reproducibility is important, simple printing, etc. It will be advantageous.

As described above, the analog method and the digital method each have advantages and disadvantages, so they are used depending on the type of image, processing purpose, application, etc.

However, there is no equipment that can combine the excellent processing of analog and digital methods, and in order to create high-definition images with good color reproducibility, digital methods are extremely expensive. It was necessary to use equipment.

Furthermore, no device has existed that allows analog and digital images to coexist on one screen.

For this reason, the applicant has already proposed an image processing device that can handle mixed and fused images of analog and digital images, has high resolution, and has excellent color reproducibility (patent application). No. 1-335304, December 25, 1999
).

This image processing device uses a spatial light modulation element using liquid crystal.
An analog writing system that writes a reflected image obtained by irradiating a document with a light source in an analog manner, a digital readout system that digitally reads out the image written on a spatial light modulation element by scanning a laser beam two-dimensionally, and a reading system. a processing unit that performs image processing on the image data processed by a; a digital writing system that digitally writes the image data that has been subjected to the above processing onto the spatial light modulation element by two-dimensionally scanning a laser beam; This system is equipped with an analog readout system that reads out images in an analog manner.

[Problems to be Solved by the Invention] In this type of image processing device, when a reflected image from a document is written to a spatial light modulation element in an analog manner, the amount of reflected light varies greatly depending on the paper quality, color, etc. of the document. I end up. Therefore, it is extremely difficult to always record images with good contrast on the spatial light modulation element, and as a result, it is difficult to always ultimately obtain high-quality images.

Therefore, an object of the present invention is to provide an image processing apparatus that can always obtain high-quality images regardless of the type of document.

[Means for Solving the Problem] The gist of the first invention of the present application which achieves the above-mentioned object is to provide a spatial light modulation element having an image writing plane and an image obtained by irradiating a document with light using spatial light. An analog writing system that writes to the modulation element in an analog manner, a digital readout system that digitally reads out the image written on the spatial light modulation element by scanning a laser beam two-dimensionally on the spatial light modulation element, and the read out image. a processing unit that performs image processing on data; a digital writing system that digitally writes an image to a spatial light modulation element based on the image data that has been subjected to the aforementioned processing by scanning a laser beam two-dimensionally; and a spatial light modulation element. an analog readout system that reads out the image written on the spatial light modulation element in an analog manner; a detection means that detects the brightness of the image written on the spatial light modulation element by the analog writing system; and means for adjusting the input sensitivity of the input signal.

A second gist of the invention of the present application that achieves the above-mentioned object is a spatial light modulator having an image writing plane, and an analog device for writing an image obtained by irradiating a document with light onto the spatial light modulator in an analog manner. A writing system, a digital readout system that digitally reads out the image written on the spatial light modulation element by two-dimensionally scanning a laser beam on the spatial light modulation element, and a processing unit that performs image processing on the read image data. a digital writing system that digitally writes an image on the spatial light modulation element based on the image data that has undergone the above processing by two-dimensionally scanning a laser beam; An analog readout system reads analog data, a detection means detects the brightness of the image written on the spatial light modulation element by the analog write system, and the intensity of light irradiated onto the document is adjusted according to the output of the detection means. The purpose is to have the means to do so.

By irradiating the original with light, an image of the original is formed on the image writing plane of the spatial light modulation element and written in an analog manner. The average brightness of the written image is detected, and the input sensitivity of the spatial light modulation element or the intensity of light irradiated onto the original is adjusted depending on the detected value. As a result, an image having constant contrast is always recorded on the spatial light modulation element. The image written on the spatial light modulation element in this manner is digitally read out for each pixel by a two-dimensionally scanned laser beam. After the read image data is subjected to desired image processing, it is digitally written again into the spatial light modulation element by a two-dimensionally scanned laser beam.

Finally, the image is read out from the spatial light modulation element in an analog manner.

[Example] Embodiments of the present invention will be described in detail below using the drawings.

FIG. 2 is a block diagram schematically showing the basic structure of a color image editing/output device as an embodiment of the present invention.

In the figure, 10 is a spatial light modulation element having an image writing plane, 11 is an analog writing system of an image to the spatial light modulation element IO, 12 is an analog reading system, 3 is a digital reading system, and I4 is a digital writing system. are shown respectively.

The digital reading system 13 and the digital writing system 14 are electrically connected to a processing section 15 that performs various image processing. The processing section 15 includes a display 16 and a control section 1.
7 is connected.

The control unit 17 is mainly composed of a computer, and includes the above-mentioned analog write system IL analog read system 1.
2, it is electrically connected to the digital reading system 13 and the digital writing system 14. In addition, in Figure 2,
White arrows represent analog optical images, black arrows represent digital optical images, and broken lines represent electrical signals.

A contrast control system 20 that controls the contrast of the spatial light modulation element 1fl is further connected to the spatial light modulation element 10 and the control section 17. The contrast control system 20 is provided with detection means for detecting the brightness of the optical image written on the spatial light modulation element 1o and means for adjusting the input sensitivity of the spatial light modulation element 10.

The spatial light modulator 10 changes the transmittance distribution, reflectance distribution, or phase distribution according to the input spatial light intensity distribution (light image). It can be stored temporarily. When the spatial light modulation element that stores an image is irradiated with other light, the transmitted light, reflected light, or scattered light is modulated according to the stored two-dimensional (spatial) image information. By detecting or exposing the modulated transmitted light, reflected light, or scattered light, the written image is read out.

The spatial light intensity distribution input to the spatial light modulator IO may be an analog image that is an optical image, or a digital image obtained by two-dimensionally scanning a modulated laser beam. . Furthermore, for reading from the spatial light modulator IQ, an analog image may be obtained by irradiating the spatial light modulator 10 with negative light, or by two-dimensional scanning with a laser beam of a constant intensity. It may also be a digital image obtained by.

The analog writing system 11 has a function of writing an optical image of the original image on the original document 18 onto the spatial light modulation element 10, and writes the optical image of the original image obtained by the light source that illuminates the original image onto the spatial light modulation element 10. It mainly consists of an optical system that forms an image on the image.

The analog readout system 12 has a function of projecting the optical image written on the spatial light modulation element 1o onto a recording paper 19 such as photosensitive paper, and has a function of projecting an optical image written on the spatial light modulation element 1o onto a recording paper 19 such as photosensitive paper. It mainly consists of an optical system that forms an image of the spatial light modulator IO on the recording paper I9.

The digital readout system 13 has a function of reading out the image written in the spatial light modulation element 10 in time series as an image signal by scanning and irradiating the image with a laser beam two-dimensionally. It mainly consists of a scanning system and a light receiving system.

The digital writing system 14 writes a digital image to the spatial light modulation element 10 based on the image signal given from the processing section 15.
It has a writing function and mainly consists of a laser light source, a laser beam scanning system, and a laser beam modulation section.

The processing unit 15 performs digital image processing on the image signal applied from the digital reading system 13 and outputs the processed image signal to the digital writing system 14. The results processed by the processing section 15 are displayed on the display 16.

Image editing and
Provides output functionality. Furthermore, an image editing function can be obtained by combining the spatial light modulation element 10, the digital reading system 13, the processing section 15, and the digital writing system 14. Further, by combining the analog writing system 11, the spatial light modulation element 10, and the digital reading system 13, an image scanner function can be obtained. Furthermore, the digital writing system 14, the spatial light modulation element IO1
By combining the analog readout system 12 and the analog readout system 12, a printer function can be obtained. An analog copying function is obtained by combining the analog writing system 1 (1), the spatial light modulation element 1 (1), and the analog reading system 12. Each of these functional modes is realized by the computer of the control section 17.

FIG. 1 shows the configuration of the embodiment shown in FIG. 2 in more detail.

The analog writing system 11 shown in FIG. 2 is R (red),
Three light sources: G (green) and B (blue) (e.g. fluorescent lamps)
It is represented by lla, llb, llc and an optical system indicated by lens lid. By sequentially illuminating the original 18 with --like light from the light sources 11a, 5Ilb, and 5Ilc, an optical image of the original image is reduced and projected onto the writing plane of the spatial light modulator 10 by the lens lid.

To separate a color image, process it sequentially.

For one original image, first turn on the R light source 11a, write the optical image on the spatial light modulator 10, read out the image, and then turn on the G light source IXb to write the optical image into the spatial light modulator 10. After writing to the light modulation element 1o and reading out the image, similar processing is performed for the B light source 11C.

In addition to the light source switching method described above, in order to obtain a color-separated image,
There is a color filter method.

This color filter method is a method in which R and GSB color filters are provided between the lens lid and the spatial light modulation element 10, and these are sequentially switched to obtain a color-separated image. Specifically, R, G, and B color filters are sequentially switched by attaching them to, for example, a rotating body and rotating the body. In the color filter method, a white light source such as a halogen light bulb is used as a light source.

Note that in the light source switching method and color filter method, the three colors of cyan, yellow, and magenta may be used instead of the three colors of R, G, and B.

The contrast control system 20 is for adjusting the dynamic range of the spatial light modulation element 10 according to the brightness of the image being written.

That is, the quality of the image recorded on the spatial light modulation element 10 is
It depends on the reflected image from the original, and if the paper quality of the original changes, the intensity of the reflected light will also change, and it is not always possible to obtain a reflected image with brightness within a certain range.

On the other hand, the dynamic range of the spatial light modulator 10 is limited. Therefore, in order to always record images with optimal contrast, it is necessary to recognize the brightness of the reflected image and match the dynamic range of the spatial light modulator 10 to this brightness.

In addition, information (for example, characters) written on a colored original in a similar color to the original is transferred to the spatial light modulation element 10.
When writing to , it may be required to always record images with good contrast, even at the expense of accurate color information.

Therefore, the contrast control system 20 uses the light receiving element 20a and the spatial light modulating element 1 as a detection means for detecting the average brightness of the image written on the spatial light modulating element 10.
The lens 20b is arranged so that the image writing plane of 0 is imaged onto the light receiving element 20a. The light receiving element 20a is connected to the control section 17 shown in FIG. 2, and its detection output is sent to the control section 17.

At least one of the light sources 11a, Nllb%, and Ilc is turned on to form an image written on the spatial light modulator 10 on the light receiving element 20a, and the brightness of the image is measured. In this case, to find out the amount of light reflected by the paper base,
The central part of the formed image is ignored and the configuration is such that reflected light from the four surrounding corners is captured. Alternatively, the light receiving elements 20a may be arranged in an array, the image written on the spatial light modulator 10 may be divided into a plurality of regions, and the average brightness of each region may be measured separately.

Further, the contrast control system 20 includes the spatial light modulator 10
A spatial light modulator 10 is used as a means for adjusting the main input sensitivity.
A power source 2Qc is provided that can control the voltage applied between the electrodes according to the detection output of the light receiving element 20a. A control input of this power source 2Dc is connected to a control section 17 (FIG. 2), and receives and receives a voltage control signal generated by the control section 17. The output of the power source 20c is connected to the picture electrode of the spatial light modulator 10. In this way, the spatial light modulator lO1
A closed loop is formed between the light receiving element 20a1 control section 17 and the power source 20c.

When the voltage applied between the electrodes of the spatial light modulator 10 increases, the sensitivity to incident light increases, and when the voltage decreases, the sensitivity to incident light decreases.

Therefore, the dynamic range of the spatial light modulator 1o is controlled by the applied voltage, and as a result, due to the above-mentioned closed loop, the optimal reflection image of the document 18 that is incident on the spatial light modulator 10 is always set. It is controlled to obtain a dynamic range.

The digital readout system 13 includes a laser light source 13a, a lens 13b, a perforated mirror 13c, a holographic scanner 13d, a galvanometer mirror 13e, and a lens 131, and a light receiving element 13g.

A laser beam with constant light intensity emitted from a laser light source 13a passes through a lens 13b and a perforated mirror 13c to a holographic scanner! Guided by 3d. The holographic scanner 13d scans the laser beam in the main scanning direction. After the laser beam passes through the holographic scanner 13d, it is applied to the galvanometer mirror 13ε and scanned in the sub-scanning direction. As a result, the laser beam is two-dimensionally scanned over the spatial light modulator 10.

By irradiating the spatial light modulation element 1o with a laser beam, transmitted light, reflected light, or scattered light at that point is modulated according to image information of a pixel corresponding to the laser beam spot. This transmitted light, reflected light, or scattered light is transmitted to the light receiving element 13.
g is applied and photoelectrically converted. In this embodiment, reflected light is used.

This reflected light follows the opposite path of the incident laser beam. That is, the light passes through the galvanometer mirror 13e and the holographic scanner 13d, is reflected by the perforated mirror 13c, is focused by the lens 131, and reaches the light receiving element Hg. In this case, the holographic scanner I3d functions as a condenser lens.

In this way, the image information written on the spatial light modulation element 10 can be read out in time series.

The digital writing system 14 includes a laser light source 14a1, a lens 14b1, a holographic scanner 1401, a galvanometer mirror 14d, and a laser modulation circuit 14e.

A signal is applied from the processing section 15 to the laser modulation circuit 14e, and the intensity of the laser beam generated from the laser light source 14a is modulated in accordance with this signal.

When a semiconductor laser is used as the laser light source 14a,
Direct modulation is possible by configuring the laser modulation circuit 14e as a circuit that modulates the drive current.

When a gas laser is used as the laser light source 142, a modulator (not shown) is required to externally modulate the emitted laser beam. In this case, the laser modulation circuit 14e is configured as a drive circuit for an external modulator.

The modulated laser beam is applied to a lens 14b to become parallel light, and then applied to a holographic scanner 14c and a galvanometer mirror 14d to be deflected in vertical and horizontal directions. As a result, the laser beam scans the spatial light modulator IO two-dimensionally. The laser modulation circuit 14e, holographic scanner 14c, and galvano mirror 14d are driven in synchronization with each other.

In this way, an image corresponding to the image data from the processing section 15 is written into the spatial light modulation element 10.

Note that the laser beam spot on the spatial light modulator Ifl corresponds to one pixel, and the light intensity represents the gradation of the pixel.

The analog readout system 12 uses three light sources of RSGXB (
For example, it has fluorescent lamps (12a, 12b, 12c) and an optical system represented by a lens 12d. Image written on spatial light modulator 10 or light source 12a %1
By being sequentially illuminated with --like light from 2b and 12c, the image is enlarged and projected onto the recording paper 19 by the lens 12d.

While the R image is being written on the spatial light modulation element 10, the R light source 12a is turned on to irradiate the spatial light modulation element 1 (l), and the recording paper 19 is exposed to the reflected light.

Similar processing is sequentially repeated for the G and B color separated images. The recording paper 19 on which the RSG and B images have been exposed in this manner is subjected to development processing to obtain a color hard copy.

Similarly to the analog writing system 11, the analog reading system 12 may also use a color filter system in addition to the light source switching system. Furthermore, instead of R, G, and B, three colors, cyan, yellow, and magenta, may be used.

To handle color image information, the above-described analog write operation, digital read operation, digital write operation, and analog read operation are sequentially performed for each color of R and GlB. That is, each operation is performed for R,
Do it for G, then do it for B, and so on.3
Repeat several times.

The laser light sources 13a and 14a are semiconductor lasers or H
A gas laser such as e-Ne (helium-neon) is used. Since semiconductor lasers are small, the entire device can be configured compactly.

Furthermore, since the gas laser has good coherence, the spot diameter of the laser beam can be made small, thereby making it possible to further improve the readout resolution.

The light receiving element 13g can be composed of a high speed photodiode. If the laser beam is shaped like a slit extending in the sub-scanning direction in order to read out several lines of image information at once (in the sub-scanning direction), a diode array or COD is used as the light receiving element.
(charge coupled device) may be used.

A rotating polygon mirror, an ultrasonic deflector, or a galvanometer mirror may be used instead of the holographic scanners 13d and 14c. Further, a holographic scanner may be used in place of the galvanometer mirrors 13e and 14d.

The processing unit 15 is mainly composed of a computer including a microprocessor, memory, etc.
It receives the image signal photoelectrically converted by e and performs image processing, that is, gradation processing (gamma correction, shading correction), sharpening (sharpness emphasis), area specification (cropping,
Performs some or all digital processing such as masking), color processing (color reproduction, paint function, color extraction), movement (rotation), and editing processing (inset composition, character composition).

Note that the processing unit 15 does not necessarily need to perform any special processing. The processing results are displayed on the display 16, and the processing can be performed interactively while checking the results. The processed image signal is output to the laser modulation circuit L4e.

Note that in FIG. 1, illustration of the control section 17 shown in FIG. 2 is omitted.

FIG. 3 shows the spatial light modulator 1 which is the main component of the present invention.
FIG.

In the figure, 10a and 10b are glass plates arranged at both ends, and an electrode 10c is laminated on the entire inside surface of one of the glass plates 10a, and a photoconductor 10d and a light shielding film are further layered on the inside of this electrode 10c. 10e are sequentially laminated. An electrode 10 is provided on the entire inner surface of the other glass plate IQb.
1 are stacked.

A spacer 10g is inserted between the electrode 10j and the light shielding film 10e, and the spacer 10g is inserted between the electrode IGe, the light shielding film 10e, and the spacer 1.
Liquid crystal IQh is injected into the space formed by 0g and sealed. The aforementioned power source 2Qc is connected to the electrodes 10c and 10f.

The electrodes 10c and 101 are transparent electrodes, and are preferably made of indium tin oxide (ITO) films.

As the photoconductor IN, cadmium sulfide (CdS), cadmium telluride (CdTe), selenium (Se), zinc sulfide (ZnS), bismuth silicate crystal (BSO), amorphous silicon, or an organic photoconductor is used. It will be done. When dealing with color images, it is best to use amorphous silicon as the photoconductor. This is because the wavelength sensitivity of amorphous silicon is flat across visible light.

The photoconductor 10d changes the molecular orientation of liquid crystal according to the input light, and other photoconductor materials whose resistance changes depending on the light can be used.

Examples include materials that generate voltage when exposed to light (for example, solar cells), materials that generate heat when exposed to light, materials whose structure changes when exposed to light (for example, photochromic compounds), and the like. Materials that generate heat when exposed to light and materials whose structure changes when exposed to light have the ability to directly change the molecular orientation of liquid crystals without electricity.

The light shielding film the is provided to prevent laser light or white light from penetrating into the photoconductor 10d when reading image information from the spatial light modulator 10. That is,
When the laser light or white light reaches the photoconductor 10d,
This is because the written information will be erased by the light. As the light shielding film 10g, an opaque film having electrical insulation properties, for example, a dielectric mirror made of silicon oxide (S i O) or the like is used.

The glass plates 10a and 1Ob are transparent and the liquid crystal 1
It functions as a substrate for sealing 0h.

Therefore, a transparent plastic plate or a transparent ceramic plate may be used instead of the glass plate.

In this embodiment, a liquid crystal having a hybrid field effect is used as the liquid crystal 10h. This liquid crystal has no memory function.

A DC voltage is applied between the electrodes 10c and 101 from a power source 20C to charge the electrodes 10c and 101 with electric charge. Thereafter, the connection between the electrode 1 (lc and It) f and the power source 211c is cut off. In this state, an optical image is incident on the photoconductor 10d by projection of planar image light or irradiation with an intensity-modulated laser beam. This causes a resistance distribution in the photoconductor 10d depending on the light intensity distribution.

That is, the resistance of the portion of the photoconductor 10d that is exposed to light decreases, and the resistance of the portion of the photoconductor 10d that is not exposed to light remains high. As a result, a voltage according to the light intensity distribution is applied to the liquid crystal 10h, the orientation of the liquid crystal molecules changes, and an input light image is written.

The factor that determines the degree of orientation of liquid crystal molecules is the voltage applied to the liquid crystal at each point. This voltage depends on the light intensity incident on the photoconductor IQd and the voltage supplied from the power supply 20c. That is, even if the intensity of the incident light changes due to, for example, the paper quality of the original 18, the liquid crystal 10 is
By controlling the voltage supplied to h, an image with a constant contrast can be written.

To erase the image written on the spatial light modulator 10, - type of light is made incident on the photoconductor 10d or the electrode 1
It is sufficient to short-circuit between 0c and lh.

As the liquid crystal 10h, a liquid crystal having a memory function (storage function) may be used. Examples of liquid crystals with memory effects include dynamic scattering (DS) liquid crystals, phase transition liquid crystals, and smectic A liquid crystals.
There are liquid crystals, ferroelectric liquid crystals, etc.

Hereinafter, as an example, write and read operations of a spatial light modulator using a dynamic scattering (DS) liquid crystal will be described.

When a DC voltage or a low frequency AC voltage of about 100 Hz is applied to a dynamic scattering liquid crystal, the liquid crystal causes dynamic scattering and becomes cloudy. This state is maintained and memorized even if the voltage is removed. Then, when a high-frequency voltage (for example, 700 Hz) higher than the cutoff frequency and relatively strong light such as - are applied, the stored image is erased. This phenomenon will be applied to spatial light modulators.

Writing to the spatial light modulator 10 is performed using the electrodes 10c and 1.
During 01, a DC voltage or a low-frequency AC voltage of about 100 Hz is applied from the power source 20c, and at the same time, a planar image light is projected onto the photoconductor 10[1 that constitutes the image writing plane or irradiated with an intensity-modulated laser beam. Inject a light image. This causes a resistance distribution in the photoconductor 10d depending on the light intensity distribution.

That is, the resistance of the portion of the photoconductor 10d that is exposed to light decreases, and the resistance of the portion of the photoconductor 10d that is not exposed to light remains high. As a result, a voltage corresponding to the light intensity distribution is applied to the liquid crystal log, and the liquid crystal in the portion to which the voltage is applied causes a scattering phenomenon.

For reading from the spatial light modulation element 10, by irradiating the entire surface of the spatial light modulation element 10 with --like light, scattered light or reflected light modulated according to the information written at each point is obtained. By imaging this with a lens, an analog image can be read out. Furthermore, when a spot light such as a laser beam is irradiated, pixel information of that spot can be read out.

Note that in order to completely erase the image written on the spatial light modulation element 10, a relatively strong light such as that on the entire surface of the photoconductor 1 (LD) is applied while a high frequency AC voltage is applied between the electrodes 10c and 101. Just irradiate it.

When a liquid crystal having a memory function is used as the liquid crystal 10h, writing is not performed unless both light and voltage are simultaneously applied to the photoconductor. That is, even if the photoconductor IQd is irradiated with a reading laser beam or -like light, the written image will not change. Therefore, it is no longer necessary to provide the light-shielding film 1 (le) as described above between the liquid crystal 10h and the photoconductor 10d to prevent light from being applied to the photoconductor IH during readout, and the readout optical system is of a transmission type. Furthermore, the reading laser beam may be applied from the glass plate 10a side or from the glass plate 10b side.Furthermore, a light shielding film foe may be provided to form a reflective type.

In particular, if the laser beam for reading a is applied from the same side as that for writing, most of the optical system in the digital writing system and the digital reading system, that is, the laser light sources 13a and 14a1 and the holographic scanner 13d.
and 1401 galvano mirrors 13e and 14d1 lenses 13b and 14b can be shared.

FIG. 4 specifically shows the configuration of another embodiment of the present invention.

This embodiment has almost the same configuration as the embodiment shown in FIG. , and the only difference is that the contrast control system 20 has a means for adjusting the intensity of light irradiated onto the document instead of a means for adjusting the input sensitivity of the spatial light modulator 10.

That is, in this embodiment, the digital readout system 13 is also used as a detection means for detecting the brightness of the optical image written on the spatial light modulation element 10.

The scanning interval of the laser beam by the digital readout system 13 is set large, and the brightness of the recorded image is roughly detected. Then, a representative value of brightness is extracted by calculating an average value or finding a maximum value and a minimum value from the brightness data of each sampled point. In order to find out the amount of light reflected by the paper surface, the central part of the image formed by the spatial light modulation element 10 may be ignored and the laser beam may be scanned concentrating on the four peripheral corners.

To increase the scanning interval of the laser beam, the light receiving element 1
Lower the sampling frequency of 3g, or use holographic scanner 13d or garno kuno mirror 13e.
All you have to do is increase the rotational speed.

As a means for adjusting the intensity of light irradiated onto the original, the fourth
As shown in the figure, light sources 11a, Ilb, llc
a light source control circuit 2 that controls at least one light emission intensity of
0d is provided. The light source control circuit 20d is connected to the control unit 17 shown in FIG. Controls luminescence intensity.

In this embodiment, the method of the embodiment shown in FIG. 1 may be used to detect the brightness of the optical image written on the spatial light modulation element 10. Conversely, the method of this embodiment may be used to check the brightness of the optical image written on the spatial light modulator IO in the embodiment of FIG.

According to the embodiment described above, a high quality image can always be obtained regardless of the type of document.

Therefore, it is very effective for compensating for differences in reflectance due to differences in paper quality of originals and for reading information such as characters from colored originals 18. In particular, when used as an analog copying machine that writes the image of the original 18 on the spatial light modulation element 10 and directly projects it onto photosensitive paper and exposes it, the spatial light modulation element lO
It can be used as a means of correcting images written on.

Further, by using the above-mentioned technique of controlling the brightness of the image written from the original 18 to the spatial light modulation element 10 so as to match the dynamic range of the spatial light modulation element 10, the image of each color is intentionally controlled differently. By doing this, it is possible to write an image with a different tone from that of the original onto the spatial light modulation element 10.

[Effects of the Invention] As explained in detail above, according to the present invention, an image obtained by irradiating light onto a spatial light modulation element having an image writing plane and an original is written on the spatial light modulation element in an analog manner. An analog writing system, a digital readout system that digitally reads out the image written on the spatial light modulation element by two-dimensionally scanning a laser beam on the spatial light modulation element, and a process that performs image processing on the read image data. a digital writing system that digitally writes an image on the spatial light modulation element based on the image data that has been subjected to the above processing by two-dimensionally scanning a laser beam; An analog readout system that reads data in an analog manner, a detection means that detects the brightness of an image written to the spatial light modulation element by the analog writing system, and an input sensitivity of the spatial light modulation element that adjusts the input sensitivity of the spatial light modulation element according to the output of the detection means. Alternatively, since the apparatus is provided with a means for adjusting the intensity of light irradiated onto the original according to the output of the detection means, a high-quality image can always be obtained regardless of the type of original.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing a color image editing/output device as an embodiment of the present invention, Figure 2 is a block diagram schematically showing the configuration of the embodiment of Figure 1, and Figure 3 is spatial light modulation. FIG. 4 is a sectional view showing an example of the structure of the element, and FIG. 4 is a block diagram showing a color image editing/output device as another embodiment of the present invention. 10...Spatial light modulation element, 10a, fob
・・・・・・Glass plate, IOc 5Lot・・・・・・
Electrode, LED...Photoconductor, 10C...
・Light shielding film, IOg...Spacer, loh...
...Liquid crystal, 11...Analog writing system, l
la, llb, llc N12a, 12b
S12cm-----Light source, lld, 12d,
13b. 131.14b, 2Gb,...lens,
12...Analog readout system, 13...
・Digital readout system, 13a114a...Laser light source, 13c...Perforated mirror, 13dN
14c...Holographic scanner, 13
e114d... Galvano mirror 113g,
2Qa... Light receiving element, 14... Digital writing system, 14e... Laser modulation circuit, 1
5...Processing unit, 16...Display, 17...Control unit, 18...Manuscript, 1
9... Recording paper, 20... Contrast control system, 20C... Power supply, 20d...
Light source control circuit.

Claims (2)

[Claims] (1) A spatial light modulator having an image writing plane, an analog writing system that writes an image obtained by irradiating a document with light onto the spatial light modulator in an analog manner, and a laser beam on the spatial light modulator. A digital readout system that digitally reads out the image written on the spatial light modulation element by two-dimensionally scanning the spatial light modulator; a processing unit that performs image processing on the read image data; a digital writing system that digitally writes an image to the spatial light modulation element based on the processed image data; an analog readout system that reads out the image written to the spatial light modulation element in an analog manner; It is characterized by comprising a detection means for detecting the brightness of an image written on the spatial light modulation element by a writing system, and a means for adjusting the input sensitivity of the spatial light modulation element according to the output of the detection means. Image processing device. (2) A spatial light modulator having an image writing plane, an analog writing system that writes an image obtained by irradiating light onto a document in an analog manner on the spatial light modulator, and a laser beam on the spatial light modulator. A digital readout system that digitally reads out the image written on the spatial light modulation element by two-dimensionally scanning the spatial light modulator; a processing unit that performs image processing on the read image data; a digital writing system that digitally writes an image to the spatial light modulation element based on the processed image data; an analog readout system that reads out the image written to the spatial light modulation element in an analog manner; The present invention includes a detection means for detecting the brightness of an image written on the spatial light modulation element by a writing system, and a means for adjusting the intensity of light irradiated onto the original according to the output of the detection means. Characteristic image processing device.