JPH03243937A - Image processor - Google Patents

Abstract

PURPOSE:To obtain a best image and to output an image with little error when scanning density of a laser beam is varied by variably controlling the scanning density of the laser beam to a desired value and to adjust a beam spot diameter of the laser beam according to the controlled scanning density. CONSTITUTION:The beam spot diameter adjustment is carried out by varying a focal distance of lens 20 and 21 by a beam spot diameter adjusting part 14b (13b), and the focal distance is varied by moving a lens 21 in the optical axis direction. A driving part to vary the focal distance of the lens 21, a variable focal lens, and a beam array changeover part are interlocked with a scanning control circuit 25, a laser modulation circuit 14d, and a light receiving element 13e, and the beam spot diameter is controlled according to the scanning density of a space light modulator element 10. Thus, when the scanning density of the laser beam of a digital reading system and a digital writing system is varied, a good image can be obtained and the image with little error can be outputted.

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, with digital color copying machines, it is difficult to achieve easy color masking and excellent color reproducibility, or to achieve high definition. As the resolution increases and the number of pixels to read increases, the amount of data increases and a high-speed processor and large-capacity memory are required, resulting in a significant cost disadvantage 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, and therefore, they are used differently 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 images that are a mixture or fusion of analog and digital images, and that has high resolution and excellent color reproducibility.

This image processing device uses a spatial light modulation element using liquid crystal.
An analog writing system that writes the original image in an analog manner, a digital reading system that digitally reads out the image written on the spatial light modulation element by two-dimensionally scanning a laser beam, and a processing unit that performs image processing on the read image data. , a digital writing system that digitally writes image data that has undergone the above processing into a spatial light modulation element by two-dimensionally scanning a laser beam, and an analog system that reads out the image written on the spatial light modulation element in an analog manner. It is equipped with a readout system.

[Problem to be solved by the invention] In the above-mentioned image processing device previously proposed by the present applicant,
By changing the scanning density of the laser beams of the digital reading system and the digital writing system, high-speed or high-quality reading and writing can be performed. For example, if the scanning density is made coarser, the image quality decreases, but since the amount of information is reduced, the scanning time and transmission time are shortened, allowing high-speed reading and writing. On the other hand, if the scanning density is made finer, high-quality reading and writing can be achieved, although it takes more time. In addition, the scanning density is made finer during readout,
If a normal scanning density is used during writing, an enlarged image can be obtained.

However, in the image processing device described above, the limit of the scanning density is determined by the beam spot diameter of the laser beam, and if the beam spot diameter is relatively large, the pixels and the beam spot cannot correspond even if the scanning density is fine. However, there were limits to the improvement of image quality.

Conversely, if you set the beam spot diameter small,
When the scanning density is made coarser, it becomes difficult to accurately represent the image. In particular, a large error occurred when reading out a pattern having a spatial frequency close to the scanning density.

Therefore, it is an object of the present invention to achieve
It is an object of the present invention to provide an image processing device that can obtain the best image quality at that scanning density and output images with fewer errors.

[Means for Solving the Problems] The features of the present invention that achieve the above-mentioned objects include a photoconductor forming an image writing plane, a liquid crystal laminated on the photoconductor, and electrodes sandwiching the photoconductor and the liquid crystal. an analog writing system for writing an original image onto the spatial light modulation element in an analog manner; and an analog writing system for writing an original image onto the spatial light modulation element in an analog manner; A digital readout system that digitally reads out an image, a processing unit that performs image processing on the readout image data, and a two-dimensional scan of a laser beam to digitally send the image data that has undergone the above processing to a spatial light modulation element. A digital writing system for writing, an analog readout system for reading out the image written in the spatial light modulation element in an analog manner, a means for variably controlling the scanning density of the laser beam to a desired value, and a means for variably controlling the scanning density of the laser beam to a desired value. and means for adjusting the beam spot diameter of the laser beam.

[Operation] First, an original image is written on the spatial light modulation element in an analog manner, and the image thus written on the spatial light modulation element is read out dentally 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.

When reading digitally, writing digitally, or both, when the scanning density of the laser beam is variably controlled to a desired value, the beam spot diameter of the laser beam changes according to the controlled scanning density. Digital readout and digital writing are performed with the adjusted beam spot diameter that is optimal for the scanning density.

[Example] Embodiments of the present invention will be described in detail below with reference to 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, 13 is a digital reading system, and 14 is a digital writing system. It shows.

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 section 17 is mainly composed of a computer, and is electrically connected to the above-described analog write system 11, analog read system 12, digital read system 13, and digital write system 14. In FIG. 2, white arrows represent analog optical images, black arrows represent digital optical images, and broken lines represent electrical signals.

The spatial light modulator 10 changes depending on the transmittance distribution, reflectance distribution, or phase distribution, or 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 10 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 out from the spatial light modulator 10, 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 an optical image written on the spatial light modulation element 10 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 10 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 10 on the recording paper 19.

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 can be obtained by combining the analog writing system 11, the spatial light modulator 10, and the analog reading system 12. Each of these functional modes is realized by the computer of the control unit 17.

The construction drawing more specifically represents the configuration of the embodiment shown in FIG. 2.

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, Ilc and an optical system indicated by lens lid. By sequentially illuminating the original 18 with -like light from the light sources 11a and Ilbs Ilc, an optical image of the original image is captured by the lens li.
d is reduced and projected onto the writing plane of the spatial light modulator 10.

To separate a color image, process it sequentially.

For one original image, first turn on the R light source 11a and write its optical image on the spatial light modulator 10, read out the image, and then turn on the G light source ITo to write the optical image into the spatial light modulator 10. After writing to the light modulation element 10 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 RSG and B color filters are provided between the lens lid and the spatial light modulation element IO, and these are sequentially switched to obtain a color-separated image. Specifically, the R and GSB 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 digital readout system 13 includes a laser light source 13a, a beam spot diameter adjustment section 13b, a laser beam scanning system 13C, a condenser lens 13d1, and a light receiving element 13e. A laser beam with a constant light intensity emitted from the laser light source 13a is applied to a beam spot diameter adjustment section 13b to adjust the spot diameter, and then applied to a laser beam scanning system 13c to be deflected in vertical and horizontal directions. As a result, the laser beam is scanned two-dimensionally over the spatial light modulator 10. Transmitted light, reflected light, or scattered light modulated according to the image information of the pixel corresponding to the laser beam spot is applied to the light receiving element 13e via the lens +3d and is photoelectrically converted. In this way, the image information written on the spatial light modulation element 10 can be read out in time series.

To obtain color image information, such a readout operation is performed for each of the R, G, and B color separated images.

The read image information is sent to the processing section 15.

The laser light source 13a is a semiconductor laser or a He-Ne (
A gas laser such as helium-neon) is used. Since semiconductor lasers are small, the entire device can be constructed 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 13e 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 image information for several lines (in the sub-scanning direction) once, a diode array or CCD is used as the light receiving element.
(charge-coupled device) may be used.

The beam spot diameter adjusting section 13b is an example of the configuration of a means for adjusting the beam spot diameter of a laser beam of the present invention, and the laser is an example of a configuration of a means for variably controlling the scanning density of a laser beam of the present invention to a desired value. The beam scanning system 13c will be explained in detail later.

The digital writing system I4 includes a laser light source 14a, a beam spot diameter adjusting section 14b1 having the same configuration as the beam spot diameter adjusting section 13b, a laser beam scanning system 14c1, and a laser modulation circuit 14d. A signal is applied from the processing section 15 to the laser modulation circuit 14d, and the intensity of the 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 modulating its driving current, but when a gas laser is used, a modulator (not shown) is required to externally modulate the emitted laser beam. It is.

The modulated laser beam is sent to the beam spot diameter adjustment section 1.
4b to adjust the spot diameter, and then applied to the laser beam scanning system 14c to be deflected in the vertical and horizontal directions. As a result, the laser beam scans the spatial light modulator 10 two-dimensionally. Spatial light modulation element 10
The upper laser beam spot corresponds to one pixel, and its light intensity represents the gradation of the pixel.

Beam spot diameter adjustment, which is an example of a configuration of means for adjusting the beam spot diameter of the laser beam of the present invention! 114b and the laser beam scanning system 14c, which is an example of a means for variably controlling the scanning density of the laser beam of the present invention to a desired value, will be described in detail later.

The laser modulation circuit 14d and the laser beam scanning system 14c operate in synchronization with each other, and write a digital image into the spatial light modulation element 10 based on a signal given from the processing section 15. To handle color image information, such a writing operation is performed for each of R, G, and B colors.

The analog readout system I2 has three light sources of R, G, and B (
For example, fluorescent lamps) 12a, 12b, 12c
and an optical system indicated by lens +2d. The image written on the spatial light modulator lO is the light source 12a11
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 10, and the recording paper 19 is exposed to the reflected light.

Similar processing is sequentially repeated for GSB color separation images. The recording paper 19 on which the R and GSB 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 H, three colors, cyan, yellow, and magenta, may be used.

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 14d.

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

Figure 3 shows the spatial light modulator +
13 is a cross-sectional view showing an example of the configuration of No. 13. FIG.

In the figure, log and lOb are glass plates placed at both ends, and an electrode 10c is laminated on the entire inside of one glass plate 10a, and a photoconductor 10d is laminated on the inside of this electrode 10c. ing. An electrode 10c is laminated on the entire inner surface of the other glass plate 10b.

A spacer +01 is provided between the electrode file and the conductor lOd.
is inserted, and a liquid crystal 10g is injected into the space formed by the electrode 10e, the conductor 10d, and the spacer 101 and sealed. A power source 10h is connected to the electrodes 10C and loe.

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

As the photoconductor IGd, cadmium sulfide (CdS),
Cadmium telluride (CdTe), selenium (Se), zinc sulfide (ZnS), bismuth silicate crystal (BSO), amorphous silicon, or an organic photoconductor is used. 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 glass plates 10a and 10b are transparent and have a liquid crystal display.
.

It functions as a substrate for sealing g.

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

For the liquid crystal 10g, a liquid crystal with a memory effect is used. For example, dynamic scattering (DS) liquid crystal, phase transition liquid crystal, smectic A liquid crystal, ferroelectric liquid crystal, etc. are used.

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 IO is performed using electrodes 10c and 1.
During 0e, a DC voltage or a low-frequency AC voltage of about 100Hz is applied from the power source 10h, and at the same time an optical image is created by projecting planar image light or irradiating an intensity-modulated laser beam onto the photoconductor 10d that constitutes the image writing plane. is incident. This causes a resistance distribution in the photoconductor 1 (ld) 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 10g, 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 IO 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, you can read out the analog image and kill it. Furthermore, when a spot light such as a laser beam is irradiated, pixel information of that spot can be read out.

In addition, in order to clean up the entire image written on the spatial light modulator 10, it is necessary to irradiate the entire surface of the photoconductor 10a with relatively strong light such as - while applying a high-frequency AC voltage between the electrodes 10c and lOe. Bye.

In order to partially erase an image written on the spatial light modulator 10, a high-frequency AC voltage is applied between the electrodes 10c and lOe, and a laser beam with a constant light intensity is applied to the portion of the photoconductor 10 (l) to be erased. The beam is scanned two-dimensionally for uniform irradiation.This partial erasure is especially necessary when a dental image with color gradation is to be overwritten on an analog image.

When a liquid crystal with a memory function is used as the liquid crystal log, writing is not performed unless both light and voltage are simultaneously applied to the photoconductor. That is, even if the photoconductor is irradiated with a reading laser beam or other light, the written image will not change.

Therefore, there is no need to provide a light shielding film between the liquid crystal and the photoconductor to prevent light from being applied to the photoconductor during reading, and the readout optical system can be of a transmission type. Moreover, the laser beam for reading is the glass plate 10a.
The voltage may be applied from the side or from the glass plate IGb side. Alternatively, a reflective type may be provided by providing a light shielding film.

In particular, if the laser beam for reading is applied from the same side as that for writing, most of the optical system can be shared by the digital writing system and the digital reading system. FIG. 4 schematically shows a configuration example of a laser beam scanning mechanism in this embodiment.

As shown in the figure, a laser light source 14a (13a)
The laser beam emitted from the optical system is focused onto the spatial light modulator 10 by lenses 20 and 21 . This laser beam is scanned by a laser beam scanning system 14c (13c) before being imaged onto the spatial light modulator 10.

The laser beam scanning system 14c (13c) includes a main scanning galvanometer 22, a sub-scanning galvanometer 23,
It mainly consists of a correction lens 24 and a scanning control section 25. The main scanning galvanometer 22 causes the laser beam spot to scan over the spatial light modulation element 10 in T rows. The sub-scanning galvanometer 23 scans the laser beam spot in a direction perpendicular to the main scanning direction. That is, when main scanning for one line is completed, the spot is moved to the next line. In this way, the spatial light modulator 1 is controlled by the main scanning galvanometer 22 and the sub-scanning galvanometer 23.
A laser vim spot is caused to scan over 0 two-dimensionally.

The correction lens 24 is provided to correct the problem that the optical path length is different between the center and the periphery of the spatial light modulation element 10, and when the center is focused, the periphery is not focused. . Such a correction lens is generally called an Fθ lens.

The scanning control circuit 25 sends control signals to the main scanning galvanometer 22 and the sub-scanning galvanometer 23.

The laser modulation circuit 14d and the light receiving element 13e also receive the signal from the scanning control circuit 25 and operate in synchronization with this signal.

The main scanning density during reading depends on the sampling frequency of the light receiving element 13e. To change the main scanning density,
This sampling frequency and sub-scanning galvanometer 23
What is necessary is to control the rotation speed of.

This allows low-resolution readout and high-resolution readout.

An enlarged image can be formed by reading out a certain arbitrary part of the spatial light modulation element 10 with high resolution and writing the readout signal at a normal density in a region having an area larger than the area of the readout part.

By doing the opposite, a reduced image can be formed.

To change the main scanning density during writing, the modulation frequency of the laser modulation circuit 14[1 and the rotation speed of the sub-scanning galvanometer 23 may be controlled.

In the configuration example shown in FIG. 4, the beam spot diameter adjustment section 14
b (13b) adjusts the beam spot diameter by changing the focal lengths of the lenses 20 and 2I. More specifically, the focal length is changed by moving the lens 21 in the optical axis direction. This has the same configuration as a so-called zoom lens, and is driven by a motor or the like.

Another way to change the focal length of the lens 21 is to configure the lens 21 with a material whose refractive index (or apparent refractive index) changes depending on the voltage, such as an electro-optic material, liquid crystal, or the like. Since this method does not require a mechanical drive unit, the device is compact and highly reliable.

In addition, a lens array is used as the lens 21,
There is a method of adjusting the beam spot diameter depending on the degree of overlapping of multiple beams by switching this.

In either method, these driving units, variable focus lenses, and beam array switching units for changing the focal length of the lens 21 are connected to the scanning control circuit 25 and the laser modulation circuit 14.
d1 and the light receiving element i3e.

The beam spot diameter is controlled according to the scanning density of the spatial light modulator 10. The relationship between the scanning density and beam spot diameter of this spatial light modulator 10 is shown in FIG.

The ratio D/p between the scanning pitch p and the beam spot diameter is ideally controlled to be as close to 1 as possible. When reading, the ratio D/p may exceed 1. However, when writing, the ratio D/p must not exceed 1.

Figures 5 (D), (E), and (F) show dot patterns when the beam spot diameter is kept constant despite changing the scanning density; is the normal scanning density, the same figure (E) is the low resolution scanning density, the same figure (E) is the scanning density of the low resolution,
F) is the case of high resolution scanning density.

Considering the time of reading, in the case of FIG. 3E, when the image written on the spatial light modulation element has a spatial frequency that is almost the same as the scanning pitch p, there is a possibility that a large read error will occur. Furthermore, in the case of FIG. 2(F), it is difficult to read out an accurate image even if the scanning density is increased.

Therefore, according to the scanning density as in this embodiment, the ratio D/p
By adjusting the beam spot diameter so that it is as close to the optimum value as possible, it is possible to obtain an image with the best image quality at that scanning density, as shown in (A), (B), and (C) of the same figure, while minimizing errors. You can get fewer images.

FIG. 6 schematically shows another configuration example of the laser beam scanning mechanism in this embodiment.

As shown in the figure, a laser light source 14i (13a)
The laser beam emitted from the hologram disk 28 is converted into parallel light by a lens 26, reflected by a mirror 27, and made incident on a hologram disk 28. The hologram disk 28 causes deflection in the main scanning direction, and the galvanometer 29 causes deflection in the sub-scanning direction. The hologram disk 23 also has a lens function, whereby the laser beam is imaged onto the spatial light modulation element 10 and scanned two-dimensionally.

The light modulated by the spatial light modulator 10 passes through a path opposite to that at the time of incidence, that is, passes through a galvanometer 29 and a hologram disk 28, and is condensed by a lens 13d.
Applied to 3e.

The scanning control circuit 30 sends control signals to the hologram disk 2B and the galvanometer 29. Laser modulation circuit 14
d and the light receiving element 13e also receive the signal from the scanning control circuit 30 and operate in synchronization with this signal.

In this configuration example, the beam spot diameter is adjusted by changing the wavelength of the laser beam emitted from the laser light source 14a (13a).

Focal length F1 of convergent light during recording on the spatial light modulator 10
The following relationship exists between the wavelength λ1, the focal length F2 of the reproduction light during reproduction, and the wavelength λ2.

Fl ・λ1 =F2 ・λ2 Therefore, if λ2 is changed while keeping F□ and λ1 constant, the focal length F2 of the reproduction light changes, and the beam spot diameter can be adjusted. If the laser light source 14a (13a) is a semiconductor laser, the wavelength λ2 can be changed by changing the applied voltage.

Note that, as shown in FIG. 7, hologram lenses 28a and 28b recorded with convergent light of different focal lengths F1 or different wavelengths λ1 are fixed concentrically to the hologram disk 28, and by moving the mirror 27 or the hologram disk 28. The laser beam is passed through the hologram lens 28
It may be configured to selectively pass through a or 28b. When recording with light having a constant wavelength λ1 and different focal lengths F1, this means that in the above equation, λ1 and λ2 are constant and F2 is controlled by changing F.

Furthermore, when the focal length F is constant and recording is performed with different wavelengths λ, this means that F2 is controlled by changing λ1 while keeping Fl and λ2 constant.

In the example of FIG. 6, it goes without saying that the various orientations described above may be used as a method for adjusting the beam spot diameter.

FIG. 8 is a flowchart schematically showing a part of the control program of the computer provided in the control@17 shown in FIG. This program is for color image editing and
This is for executing the output function mode, and when this mode is specified, the computer operates as follows.

First, in step S1, a flag n for switching between RSG and B is initially set to n4-0.

Next, in step S2, it is determined whether n=0.

If n=0, the analog write system 1 is
The R light source 11a of No. 1 is turned on, and in the next step S4,
An optical image of the original 18 by -like light from the R light source 11a is written on the spatial light modulation element 10 via the lens LLd.

If n=o is not true in step S2, it is determined in step S5 whether n=1.

If n=1, the G light source 11b is turned on in step S6, and the G light source 11b of the original 18 is turned on in the next step S4.
An optical image based on --like light from the . If n=1, the B light source 11ε is turned on in step S7, and in the next step S4, an optical image of the document 18 by -like light from the B light source 11C is spatially modulated via the lens lid. Element 1
Write to 0.

In the next step S8, the digital readout system 13
Activate. That is, the laser beam emitted from the laser light source 13a is two-dimensionally scanned on the spatial light modulator 10, and the transmitted light, reflected light, or scattered light is transmitted to the light receiving element 13.
The image information written on the spatial light modulation element 10 is read out by applying the voltage to d.

Next, in step S9, the processing unit i5 is activated,
Various image processing is performed on the read image information.

In the next step 510, the digital writing system 14 is activated. That is, a signal from the processing section 15 is applied to the laser modulation circuit 14c, and the laser beam is modulated to two-dimensionally scan the spatial light modulation element 10 for writing. At the time of this digital writing, the digital image may be written on the entire spatial light modulation element 10, or may be written on a portion thereof. This makes it possible to obtain an image in which an analog image and a digital image are mixed and fused.

In step Sll, it is determined whether all the image processing by the processing unit 15 has been completed, and if not, steps 38 to
Repeat the process of SI[l.

In the next step S12, it is determined whether n=o. If n=0, the process proceeds to step SI3 and the R light source 12a of the analog readout system 12 is turned on. Then, in the next step 314, the image information written on the spatial light modulation element 10 is read out using --like light from the R light source t2a, and the optical image is exposed onto the recording paper 9 through the lens I26. let

If n=0 in step S12, step S1
5, it is determined whether n=1. n=1
In this case, the G light source 12b is turned on in step S16, and in the next step S14, the image information written on the spatial light modulation element 10 is read out using --like light from the G light source 12b, and the The optical image is exposed onto the recording paper 19 through the lens 12d. If it is not n-1, the B light source 12c is turned on in step S17, and the process proceeds to the next step S1.
At step 4, the image information written on the spatial light modulator 10 is read out using the -like light from the B light source 12c, and the optical image thereof is exposed onto the recording paper 19 through the lens 12d.

Next, in step S18, n is incremented by n4-n+1, and then, in step S19, it is determined whether n=3. If n=3, RSG.

This program is terminated assuming that processing of all colors of B has been completed. If n=3, the process returns to step S2 and the above-described process is repeated.

When the color image editing function mode is instructed, the computer executes only steps S8 to S11 of the program in FIG. 8. However, the processing from step 58 to Sll is repeatedly executed for all R, G, and B colors.

If you are prompted to enter image scanner function mode, switch to the 8th
Only steps 31 to S8 of the program shown in the figure are executed. In this case as well, the process is repeated for all R, G, and B colors. That is, the process is repeated until n-3 is reached.

If the printer function mode is instructed, step 32G of the program in FIG. 8 is executed first, and image information is input from the control unit 17 or other external device. Next, the processing from step S10 onwards is executed. However, these processes are repeatedly executed for all R, G, and B colors.

When the analog copy function mode is instructed, the process is executed in such a way that the program always jumps from step S4 to step S12 in the program shown in FIG.

According to this embodiment, analog processing or digital processing can be used depending on the type of image and the like. for example,
For images mainly consisting of line drawings or characters, smooth lines can be reproduced by instructing the analog copy function mode and performing analog processing.

Furthermore, for images where color is important, color correction and the like can be performed by instructing the color image editing/output function mode to faithfully reproduce the colors.

Color image editing and image area separation that is difficult with analog processing
It can be easily processed by instructing the output function mode and color image editing function mode and performing digital processing such as partial self-writing. Furthermore, it is also possible to obtain an image in which analog and digital images are mixed or fused, such as by fitting an analog image into a digital image, fitting a digital image into an analog image, or overwriting a digital image on an analog image.

[Effects of the Invention] As described above in detail, the present invention includes means for variably controlling the scanning density of a laser beam to a desired value, and adjusting the beam spot diameter of the laser beam in accordance with the controlled scanning density. Because it is equipped with a means for An image processing device can be realized.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic structure of a color image editing/output device as an embodiment of the present invention, FIG. 2 is a block diagram schematically showing the structure of the embodiment of FIG. 1, and FIG. FIG. 4 is a cross-sectional view showing an example of the configuration of a spatial light modulation element, FIG. 4 is a schematic diagram of an example of the configuration of the laser beam scanning mechanism in the embodiment of FIG. 1, and FIG. 5 shows a dot pattern in the spatial light modulation element. 6 is a schematic diagram of another configuration example of the laser beam scanning mechanism in the embodiment of FIG. 1, FIG. 7 is a diagram of the configuration of the hologram disk, and FIG. 8 is a diagram of the computer of the embodiment of FIG. 1. 3 is a flowchart schematically showing a part of a control program. 10...Spatial light modulation element, lOa, Job・
...Glass plate, 10c, lQe...
Electrode, 1 (ld... photoconductor, 101...
...Spacer, 10g...LCD, 10h...
...Power supply, 11...Analog writing system, l
la % llb z Ilc 512aS12b11
2C...Light source, lld, 12d, +3
d. 20.21.26...Lens, 12...
・Analog readout system, 13...Digital readout system, 13a, 14a...Laser light source,
! 3b, 14b... Beam spot diameter adjustment section, 13C, '14c... Laser beam scanning system, L3t... Light receiving element, 14... Digital writing system , 14d... laser modulation circuit,
15...Processing unit, 16...Display, 17...Control unit, 18...Manuscript,
19...recording paper, 22.23.29...
... Galvanometer, 24 ... Correction lens, 25. 30... Scanning control circuit, 28... Hologram disk, 8a 8b... Hologram lens. Figure 2 Figure 3 Figure 4 Figure 6 Figure 7

Claims (1)

[Claims] A spatial light modulator comprising a photoconductor constituting an image writing plane, a liquid crystal layered on the photoconductor, and electrodes sandwiching the photoconductor and liquid crystal; an analog writing system for writing data, a digital readout system for digitally reading out an image written on the spatial light modulation element by scanning a laser beam two-dimensionally over the spatial light modulation element, and the read image data. a processing unit that performs image processing; a digital writing system that digitally writes the processed image data to the spatial light modulation element by two-dimensionally scanning a laser beam; An analog reading system for reading out images in an analog manner, means for variably controlling the scanning density of the laser beam to a desired value, and means for adjusting the beam spot diameter of the laser beam in accordance with the controlled scanning density. An image processing device characterized by: