JP3019408B2 - LCD exposure equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal exposure apparatus used for an image recording apparatus for printing out image data and character data of a video signal, a personal computer or the like, and more particularly to a liquid crystal exposure apparatus. The present invention relates to a high-resolution liquid crystal exposure apparatus.

[Related Art] In recent years, a liquid crystal display panel using a liquid crystal display element (LCD) that switches between light transmission and light blocking using various electro-optic effects in liquid crystal has been developed. Here, a twisted nematic (TN) type LCD will be described. In this TN type LCD, a plurality of liquid crystal light modulating elements are arranged. In each liquid crystal light modulating element, the liquid crystal has two transparent electrode substrates (outside) and two alignments having uniform linear grooves. It is sandwiched between the membrane (inside). When no voltage is applied between the transparent electrodes, the liquid crystal molecules assume a specific alignment state according to the force regulated by the grooves of the alignment film. Since the liquid crystal molecules are shifted by 90 degrees, the liquid crystal molecules show a twisted structure in the molecular major axis direction, and the alignment of the liquid crystal molecules is twisted by 90 degrees between both alignment films. When the TN-type liquid crystal light modulation element in this state is sandwiched between two polarizing plates whose polarization directions are orthogonal to each other, and a light beam enters from one of the polarizing plates, the light beam is linearly polarized by the first polarizing plate. Then, while the linearly polarized light travels in the liquid crystal, the polarization direction of the linearly polarized light is rotated by 90 degrees due to the birefringence of the liquid crystal molecules and the 90-degree twisted alignment structure as described above. As a result, the polarization direction of the linearly polarized light matches the polarization direction of the other polarizing plate, and the linearly polarized light is emitted as it is. However, when a voltage is applied between the transparent electrodes, the liquid crystal molecules are forcibly aligned in the direction of the electric field.
The twisted orientation structure is not formed. Therefore, the linearly polarized light incident from one of the polarizers reaches the other polarizer without rotating the polarization direction. Is done. In this way, the LCD that blocks light when voltage is applied
Is called Normally White. Conversely, an LCD that sandwiches a TN type liquid crystal light modulation element between two polarizing plates having the same polarization direction and transmits light when a voltage is applied is referred to as normally black.

Switching between light transmission and light blocking as described above is performed by applying a voltage between the transparent electrodes. By arranging a plurality of LCDs in a lattice, a liquid crystal display panel having a high response speed can be provided.

Paying attention to such characteristics of the liquid crystal display panel, various liquid crystal exposure apparatuses using the liquid crystal display panel as an optical shutter have been developed. Usually, in such a liquid crystal exposure apparatus, the resolution of the liquid crystal display panel is the resolution of an image such as a character as it is.

[Problems to be solved by the invention]

However, with the resolution of the liquid crystal display panel in the conventional liquid crystal exposure apparatus as described above, it was impossible to express soft lines such as oblique lines originally possessed by characters. In order to improve the resolution of the liquid crystal exposure apparatus, it is necessary to increase the resolution of the liquid crystal display panel itself, which causes a problem of increasing the manufacturing cost.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a liquid crystal exposure apparatus in which the resolution of an image such as a character is increased without increasing the resolution of a liquid crystal display panel.

[Means for solving the problem]

In order to achieve such an object, the present invention provides a liquid crystal display panel including a plurality of liquid crystal light modulation elements, and a liquid crystal display panel drive control unit for displaying an image on the liquid crystal display panel based on an image signal. Image forming optical means for forming an image displayed on the liquid crystal display panel on a photosensitive recording medium using light condensed on the liquid crystal display panel, and In a liquid crystal exposure apparatus for exposing the photosensitive recording medium with an image,
A first character pattern used for the second exposure is generated, and when the first character pattern is superimposed on the first character pattern in the second exposure, the resolution of the same character is improved with respect to the first character pattern. And a liquid crystal display panel, the photosensitive recording medium, and the image forming optical unit after the first exposure using the first character pattern. At least one of them is slightly moved in a direction oblique to the arrangement direction of the liquid crystal light modulation elements by a distance corresponding to half the size of the liquid crystal light modulation elements, The second using a character pattern
And a moving means for performing the second exposure.

[Action]

According to the present invention, the image displayed on the liquid crystal display panel by the liquid crystal display panel drive control means is emitted by irradiating the light from the light source transmitted through the liquid crystal display panel and the imaging optical means onto the photosensitive recording medium. It is exposed on a photosensitive recording medium.

At this time, the character generator generates a first character pattern used for the first exposure,
In the second exposure, a second character pattern which is complementary to the first character pattern for improving the resolution is generated for the same character when superimposed on the first character pattern.

Then, after the first exposure using the first character pattern, the moving unit moves at least one of the liquid crystal display panel, the photosensitive recording medium, and the imaging optical unit in the arrangement direction of each liquid crystal light conversion element. Then, the liquid crystal light modulation element is slightly moved in a diagonal direction by a distance corresponding to a half of the size of each liquid crystal light modulation element, and the second exposure using the second character pattern is performed.

Therefore, when the first exposure is performed using the first character pattern generated by the character generator,
At least one of the liquid crystal display panel, the photosensitive recording medium, and the imaging optical means corresponds to half the size of the liquid crystal light modulation element in a direction oblique to the arrangement direction of each liquid crystal light modulation element. Then, a second exposure is performed by using a second character pattern that is complementary to the first character pattern to improve the resolution of the same character with respect to the first character pattern. Since the exposure is completed, the first
In the character pattern described above, the space between the liquid crystal light modulation elements adjacent to each other in a direction oblique to the arrangement direction of the liquid crystal light modulation elements is filled with the second character pattern, and character exposure with high resolution can be performed.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an image recording apparatus of the present invention.
In FIG. 1, an image recording apparatus 1 includes a liquid crystal exposure apparatus 2, and is configured such that an elongated microcapsule paper 10 as a photosensitive recording medium is conveyed in an exposure area below the liquid crystal exposure apparatus 2. .

The liquid crystal exposure apparatus 2 includes a halogen lamp 3 as a light source, a reflector 4 disposed above the halogen lamp 3,
A condenser lens 5 disposed below the halogen lamp 3;
A liquid crystal display panel (hereinafter, referred to as an LCD panel) 8 disposed below the condenser lens 5 via an infrared cut filter 6 and a color filter unit 7 and an imaging lens 9 are provided.

The LCD panel 8 includes an X-axis moving device 26 for moving the LCD panel 8 in the X-axis direction (perpendicular to the drawing).
And a Y-axis moving device 27 for moving the LCD panel 8 in the Y-axis direction (a direction parallel to the drawing). The LCD panel 8 is configured to be minutely moved by the X-axis moving device 26 and the Y-axis moving device 27 in a direction oblique to the arrangement direction of the liquid crystal light modulation elements of the LCD panel 8.

The microcapsule paper 10 has a plurality of microcapsules applied on the surface of a long support, and the microcapsules contain a dye precursor or the like that reacts with a developer described later. Then, unexposed microcapsule paper 10
Is mounted in the light-shielding cartridge 17 while being wound around the cartridge shaft 15. This cartridge 17
The microcapsule paper 10 pulled out of the LCD panel 8 is exposed in a stationary state under the LCD panel 8 to form a latent image. Then, the microcapsule paper 10 that has been exposed is
In a state of being superimposed on the color developing paper 18, the pressure is applied by the pressure rollers 11a and 11b to perform pressure development. Thereafter, the microcapsule paper 10 separated from the color developing paper 18 is wound around the cartridge shaft 16.

Above the pressure rollers 11a and 11b, a cassette in which a plurality of developer sheets 18 are stacked and accommodated is mounted. A half-moon roller 19 is provided at the upper left of the cassette.
18 are fed one by one between the paper feed rollers 20 and 20. The developer paper 18 sent out has a microcapsule paper 10
The latent image is conveyed to the pressure rollers 11a and 11b at a timing such that the position of the latent image matches the position of the top of the latent image.

Developing paper 18 has a developer applied to the surface of the support,
It reacts with the dye precursor contained in the microcapsules of the microcapsule paper 10 to form a color, but see U.S. Pat.
No. 399,209, and the description is omitted here.

A heat fixing device 12 is disposed to the right of the pressure rollers 11a and 11b, a heater 13 is provided inside the heat fixing device 12, and a transport belt 14 for transporting the developing paper 18 is provided below the heat fixing device 12.
Are arranged.

Here, an electrical configuration of the image recording apparatus 1 will be described. Data output from the outside is input to the image recording apparatus 1 by the video I / F circuit 21. The data is digitized by an A / D conversion circuit 22, where it is separated into red (R), green (G), and blue (B).
Is stored in The character pattern formed by the character generator 28 is also stored in the video RAM 23. On the other hand, when the print start switch 25 is depressed, the signal of the print start switch 25 is transferred to a CPU (not shown). And the LCD panel controller by CPU
24 is controlled, and a signal is sent to a moving device control circuit (not shown) to control the X-axis moving device 26 and the Y-axis moving device 27.

 Next, the operation of the image recording apparatus 1 will be described.

When the print start key 25 is depressed, first, an image corresponding to the red (R) image signal input from the outside is displayed on the LC.
Displayed on the D panel 8. Next, the halogen lamp 3 is turned on, and the light from the halogen lamp 3 is efficiently condensed by the reflector 4 and the condenser lens 5 to become parallel light, and enters the LCD panel 8 through the infrared cut filter 6 and the red filter 7R. I do. The light passing through the LCD panel 8 on which the image corresponding to the red (R) image signal is displayed as described above is imaged on the microcapsule paper 10 by the imaging lens 9 and is exposed. . When the red exposure is completed, the red filter 7R is replaced with the green filter 7G, and an image corresponding to the green (G) image signal is displayed on the LCD.
Displayed on panel 8. Then, green exposure is performed in the same manner as red exposure. Similarly, blue exposure is performed using the blue filter 7B according to the blue (B) image signal. Thus, a latent image of a color image is formed on the microcapsule paper 10. Thus, the first exposure is completed.

Next, a signal is sent to a moving device control circuit (not shown), and the Y-axis moving device 26 and the Y-axis moving device 27 are driven, so that the LCD panel 8 is moved by 1/2 pixel in the X-axis direction and the Y-axis direction. Moved by distance. Then, the character pattern formed by the character generator 28 and stored in the video RAM 23 is L
The data is loaded into the CD panel controller 24, and the second exposure of the character portion is performed in the same manner as described above.

The double exposure of such a character improves the resolution of the character. This will be described with reference to FIGS. 2 and 3. FIG. 2 is a view showing the double exposure of the white character of X (only the character portion is in a light transmitting state). First, the character pattern a is exposed by the first exposure. Next, the character pattern b formed by the character generator 28 is exposed by moving the LCD panel 8 by a distance of 1/2 pixel in each of the X-axis direction and the Y-axis direction. As a result, the area between the pixels of the character pattern a which has been exposed first is exposed by the second exposure, and the resolution of the character as an exposure result is improved.

FIG. 3 is a view showing the double exposure of a black character X (only the character portion is in a light-shielded state). First, the exposure of the character pattern c is performed by the first exposure. Next, LC
The character pattern d formed by the character generator 28 is exposed by moving the D panel 8 by a distance of 1/2 pixel in each of the X-axis direction and the Y-axis direction. As a result, the pixels between the pixels of the character pattern c that have not been exposed first are exposed by the second exposure, and the resolution of the character as an exposure result is improved.

When the exposure is completed as described above, the microcapsule paper 10 is moved by the driving force of the winding roller 16 to the pressure roller 11.
It is transported in the directions a and 11b. On the other hand, the colored paper 18
The sheet is fed one by one by 9, and is conveyed to pressure rollers 11 a and 11 b by a feed roller 20. Then, in a state where the exposed surface of the microcapsule paper 10 and the developer application surface of the developed paper 18 are overlapped so as to be in contact with each other, pressure is applied by the pressure rollers 11a and 11b, and the image is transferred to the developed paper 18. The developing paper 18 is further conveyed by the conveyer belt 14, while the color development is promoted by the heater 13 of the thermal fixing device 12, and is output as an image.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, two exposures are performed for the character portion. However, three or more exposures are performed by making the moving distance of the LCD panel 8 shorter one time, and even if the resolution is made higher. Good. Further, in the above-described embodiment, the LCD panel 8 is moved obliquely, but the microcapsule paper 10 or the imaging lens 9 may be moved, or a diagonal fine movement by a combination of these may be performed. In addition, although a halogen lamp is used as a light source, a metal halide lamp can be used.
Furthermore, the replacement order of the color filters is not limited to RGB.

In this embodiment, a color liquid crystal exposure apparatus is used by using a color filter. However, a monochrome liquid crystal exposure apparatus may be used without a color filter.

〔The invention's effect〕

As described in detail above, according to the present invention, after performing the first exposure using the first character pattern generated by the character generator, the liquid crystal display panel, the photosensitive recording medium, and the imaging optical unit are formed. At least one of them is slightly moved by a distance corresponding to a half of the size of the liquid crystal light modulation element in a direction oblique to the arrangement direction of each liquid crystal light modulation element, and then the first character By performing the second exposure using the second character pattern complementary to the same character with respect to the pattern, the exposure of one character is completed. Therefore, the arrangement of the liquid crystal light modulation elements in the first character pattern The space between the liquid crystal light modulation elements adjacent to each other in a direction oblique to the direction is filled with the second character pattern, thereby enabling high-resolution character exposure.

Therefore, the resolution of the characters to be exposed can be improved without increasing the resolution of the liquid crystal display panel.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image recording apparatus using the liquid crystal exposure apparatus of the present invention, FIG. 2 is a view showing double exposure in an X white character, and FIG. 3 is a view showing double exposure in a black X character. FIG. DESCRIPTION OF SYMBOLS 1 ... Image recording apparatus, 2 ... Liquid crystal exposure apparatus, 3 ... Halogen lamp, 4 ... Reflector, 5 ... Condenser lens (condensing optical means), 6 ... Infrared cut filter,
7R, 7G, 7B: color filter, 8: LCD panel, 9
…… Imaging lens (imaging optical means), 10… Microcapsule paper (photosensitive recording medium), 24 …… LCD controller, 26
... X-axis moving device (moving means), 27 ... Y-axis moving device (moving means), 28 ... Character generator.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02F 1/13 505 G02F 1/135 G03B 27/00

Claims (1)

(57) [Claims] A liquid crystal display panel comprising a plurality of liquid crystal light modulation elements; a liquid crystal display panel drive control means for displaying an image on the liquid crystal display panel based on an image signal; Image forming optical means for forming the image displayed on the liquid crystal display panel on a photosensitive recording medium using the generated light, and exposing the photosensitive recording medium with the image based on the image signal. In the liquid crystal exposure apparatus, a first character pattern used for the first exposure is generated, and when the first character pattern is superimposed on the first character pattern in the second exposure, the first character pattern is generated for the same character.
A character generator that generates a second character pattern in a complementary relationship with respect to the character pattern for improving resolution, after the first exposure using the first character pattern, the liquid crystal display panel, At least one of the photosensitive recording medium and the image forming optical unit corresponds to half the size of the liquid crystal light modulation element in a direction oblique to the arrangement direction of the liquid crystal light modulation elements. A moving means for slightly moving by a distance to perform the second exposure using the second character pattern.