JPH04149421A - Liquid crystal exposure device - Google Patents

Abstract

PURPOSE:To remove an unexposed part due to the projection of the black mask of an LCD shutter and to form images of high quality by exposing a photosensitive recording medium through a light diffusion film. CONSTITUTION:The device is equipped with a halogen lamp 3 as a light source, a reflector 3a which reflects the projection light from the halogen lamp 3, a condenser lens 3b as a light converging means which collimates the projection light from the halogen lamp 3 and the reflected light from the reflector 3a into parallel light beams, the LCD shutter 5 consisting of plural liquid crystal optical modulating elements 5a, the light diffusion film 6 which is arranged between the LCD shutter 5 and photosensitive recording medium 20 at the time of exposure and diffuses light incident on the LCD shutter 5. And a film feeding device 7 which conveys the light diffusion film 6 at the speed equal to the conveying speed of the photosensitive recording medium 20. In this case, the light which is emitted by the light source, collimated by the condenser lens 3b, and then transmitted through the LCD shutter 5 is diffused by the light diffusion film 6 between the LCD shutter 5 and photosensitive recording medium 20 to irradiate the photosensitive recording medium 20. Consequently, an image of an electric wiring pattern never appears on the photosensitive recording medium 20.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a liquid crystal exposure device used in an image recording device for printing out images, character data, etc. based on a video signal, etc., and particularly relates to an LCD shutter and The present invention relates to a liquid crystal exposure device that improves image quality by providing a light diffusion film between the photosensitive recording medium and the photosensitive recording medium.

[Conventional technology]

In recent years, various liquid crystal display elements (LCDs) have been developed that utilize various electro-optic effects in liquid crystals to switch between light transmission and light blocking.
) shutter has been developed.

Here, among the LCD shutters, a twisted nematic (TN) type LCD shutter will be explained. This TN type LCD shutter is made up of a plurality of liquid crystal light modulation elements arranged, and in each liquid crystal light modulation element, the liquid crystal is formed by two transparent electrode substrates (outside) and two sheets having uniform linear grooves. It is sandwiched between orientation M (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 films, but the groove directions of the two alignment films are mutually Because they are shifted by 90 degrees, the liquid crystal molecules exhibit a twisted structure in the long axis direction of the molecules.
The alignment of 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 perpendicular to each other, and a light beam is incident from one of the polarizing plates, the light beam becomes linearly polarized light at the first polarizing plate. While this linearly polarized light travels through the liquid crystal, due to the birefringence of the liquid crystal molecules and the above-mentioned 90 degree twisted alignment structure,
The polarization direction of the above linearly polarized light is rotated by 90 degrees. As a result, the polarization direction of the linearly polarized light matches the polarization direction of the other polarizing plates, and the linearly polarized light is emitted as 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, so that the above-mentioned 90 degree twisted alignment structure of the liquid crystal molecules is not formed. Therefore, the linearly polarized light incident from one polarizing plate reaches the other polarizing plate without rotation of the polarization direction, and when it is output, the polarization direction of the linearly polarized light and the polarization direction of the other polarizing plate are orthogonal and the light is blocked. be done.

The 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 liquid crystal light modulation elements, a shutter with high response speed becomes possible.

Focusing on the characteristics of such LCD shutters, we
Various liquid crystal exposure devices using shutters have been developed. Normally, in such a liquid crystal exposure apparatus, an LCD shutter is brought into direct contact with a photosensitive recording medium to expose the medium and output an image.

[Problem to be solved by the invention]

However, the resolution of the LCD shutter is fixed by the arrangement of multiple liquid crystal light modulation elements;
When exposing with the D shutter in close contact with the photosensitive recording medium,
There is a problem in that the wiring pattern of the LCD shutter and the like are directly exposed to light on the photosensitive recording medium, resulting in a reduction in image quality, especially when outputting images such as photographs. Also,
In order to change the exposure resolution, it is necessary to replace the LCD shutter with one that corresponds to the desired resolution, making the operation complicated, and having several types of LCD shutters increases costs. . Furthermore, there was also the problem that particles of the photosensitive recording medium adhered to the surface of the LCD shutter.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a liquid crystal exposure apparatus that can easily change the resolution without replacing the LCD shutter.

[Means to solve the problem]

In order to achieve such an object, the present invention provides a liquid crystal exposure apparatus that exposes a photosensitive recording medium based on an image signal, the liquid crystal exposure apparatus comprising a light source, an LCD shutter consisting of a plurality of liquid crystal light modulation elements, and an exposure device. a light diffusion film that is sometimes placed between the LCD shutter and the photosensitive recording medium and that diffuses the light incident on the LCD shutter; and a film feeding device that conveys the light diffusion film at the same speed as the conveyance speed of the photosensitive recording medium. , and a condensing means for converting the light from the light source into parallel light.

[Effect]

After being emitted from a light source and collimated by a condenser lens, the light transmitted through the LCD shutter is diffused by a light diffusion film between the LCD shutter and the photosensitive recording medium, and is irradiated onto the photosensitive recording medium. This results in
The exposed area of the LCD shutter is enlarged, and the projected area of the black mask (unexposed area) of the LCD shutter is also exposed, so that no image of the wiring pattern appears on the photosensitive recording medium.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

First, an example of an image recording apparatus using the liquid crystal exposure apparatus of the present invention will be described. FIG. 1 is a schematic diagram of an image recording apparatus using a liquid crystal exposure apparatus of the present invention. In FIG. 1, an image recording device 1 includes a liquid crystal exposure device 2, and is configured such that a long microcapsule paper 20 as a photosensitive recording medium is conveyed through an exposure area 15 below the liquid crystal exposure device 2. There is.

The liquid crystal exposure device 2 includes a halogen lamp 3 as a light source and a reflector 3 that reflects light emitted from the halogen lamp 3.
a % A condenser lens 3b as a condensing means that converts the emitted light from the halogen lamp 3 and the reflected light from the reflector 3a into parallel light, and converts the light passing through this condenser lens 3b into a single color of red, green, or blue. Filter 4R to be disassembled.

4G, 4B, LCD shutter 5, light diffusion film 6,
It is equipped with film feed devices 7.7, 7.7 and microcapsule paper feed rollers 23, 23°23.

The microcapsule paper 20 has a plurality of microcapsules coated on the surface of a long support, and the microcapsules contain a dye precursor that reacts with a color developer described later. And unexposed microcapsule paper 20
is mounted in a light-shielding cartridge 21 in a state where it is wound around a cartridge shaft 22. Further, on the right side of this cartridge 21, there are provided feed rollers 23, 23.degree. 23 for conveying the microcapsule paper 20 at a predetermined speed.

The microcapsule paper 20 exposed in the lower exposure area 15 of the liquid crystal exposure device 2 is transferred to the pressure roller 30a with the developer paper 635 superimposed thereon.

30b for pressure development. Thereafter, the microcapsule paper 20 separated from the developer paper 35 is wound around a cartridge shaft 27 disposed within the cartridge 26.

Above the pressure rollers 30a and 30b, a plurality of color developing papers 3
A cassette 37 containing cassettes 5 and 5 is installed. A half-moon roller 41 is disposed at the upper left of the cassette 37, and the rotation of the half-moon roller 41 feeds out the color developing paper 35 one by one between paper feed rollers 42, 42. The fed out developing paper 35 is fed to the feed guide 4
3, and is conveyed to pressure rollers 30a and 30b at a timing such that the leading edge of the color developer paper 35 and the leading edge of the latent image on the microcapsule paper 20 are aligned.

The color developer paper 35 has a color developer coated on the surface of the support.
It reacts with the dye precursor encapsulated in the microcapsules of the microcapsule paper 20 to develop a color, but the details are described in US Pat.

A heat fixing device 50 is arranged on the right side of the pressure rollers 30a and 30b, a heater 51 is provided inside this heat fixing device 50, and a conveyor belt 52 for conveying the color developer paper 35 is provided at the bottom. is installed.

Next, the liquid crystal exposure apparatus 2 of the present invention will be explained with reference to FIGS. 2 to 4. FIG. 2 is an external perspective view of a main part of the liquid crystal exposure apparatus 2 shown in FIG. 1.

In FIG. 2, the liquid crystal exposure device 2 includes a halogen lamp 3 as a light source and a reflector lens 3 as described above.
A condenser lens 3b, and filters 4R, 4G, and 4B that separate the parallel light that has passed through the condenser lens 3b into monochromatic colors of red, green, and blue.

LCD shutter 5, microcapsule paper 20, feed rollers 23, 23, 23 that transport microcapsule paper 20 at a predetermined speed, light diffusion film 6, and transport this light diffusion film at the same speed as the transport speed of microcapsule paper 20. The film feeding device 7, 7, 7.7 is provided with

The LCD shutter 5 includes a plurality of liquid crystal light modulation elements 5a,
Black mask 5 arranged between each liquid crystal light modulation element 5a
b, and two transparent electrode plates 5c, 5c (third
(see figure).

FIG. 4 is a plan view showing the arrangement of the liquid crystal light modulation elements 5a, and each liquid crystal light modulation element 5a is arranged at equal intervals. Each liquid crystal light modulation element 5a constitutes one pixel. As described above, the LCD shutter 5 is controlled by a controller (not shown) based on an image signal, and light is transmitted only through pixels in a light transmitting state.

The filters 4R, 4G, and 4B are driven by a filter drive device (not shown), and a filter of a color corresponding to the image signal that controls the LCD shutter 5 is inserted into the optical path. The parallel light that has passed through the condenser lens 3a is filtered by a filter 4R.

4G and 4B separate it into single colors of red, green or blue,
The light passes through the liquid crystal pixel 5a portion of the LCD shutter 5. In the liquid crystal exposure apparatus 2 of the present invention, during exposure,
A light diffusion film 6 is disposed between the LCD shutter 5 and the microcapsule paper 20, and as shown in FIG.
As a result, the light path is diffused to the black mask (unexposed area) 5b and exposure is performed, so that no unexposed area is generated due to the projection of the black mask 5b on the paper of the microcapsule 20.

Further, in the liquid crystal exposure apparatus 2 of the present invention, the light diffusion film 6
is endlessly circulated between four film feeding devices 7, 7° 7.7, and the circulation speed (film transport speed)
The feed roller 23.23.2 of the microcapsule paper 20 is set so that the speed is equal to the conveyance speed of the microcapsule paper 20.
It is driven in synchronization with 3. That is, cartridge shaft 2
When the microcapsule paper 20 wound around the microcapsule paper 20 is conveyed by the microcapsule paper feed rollers 23, 23.23, the film feed devices 7.7.7.
7 is driven, and when passing through the exposure area 15, the light diffusion film 6
and the microcapsule paper 20 are conveyed at a constant speed and in close contact with each other without shifting. Therefore, the surface of the microcapsule paper 20 is prevented from being scratched by friction with the light diffusion film 6. Furthermore, since the light diffusion film 6 is interposed between the LCD shutter 5 and the microcapsule paper 20, the particles of the microcapsule paper 20 are not directly attached to the surface of the LCD shutter 5, and the particles of the microcapsule paper 20 are not directly attached to the surface of the microcapsule paper 20. It is possible to make the dispersion of light uniform.

Next, the operation of the image recording device 1 will be explained.

When the print start key (not shown) is pressed down, the halogen lamp 3 is turned on, and the reflected light from the reflector 3a and the emitted light from the halogen lamp 3 are collimated by the condenser lens 3b, and then passed through the red filter 4.
The light is turned into red light by R and enters the LCD shutter 5. This LCD shutter 5 is controlled by a controller (not shown) in accordance with a red (R) image signal. Each pixel of the LCD shutter 5 (liquid crystal light modulation element 5a
) is diffused by the light diffusion film 6 and irradiated onto the microcapsule paper 20, completing the red exposure. Next, green exposure is performed using the green filter 4G in accordance with the green (G) image signal. Similarly, blue exposure is performed using the blue filter 4B in accordance with the blue (B) image signal. As a result, a latent color image is formed on the microcapsule paper 20. During this time, the microcapsule paper 20 stops being conveyed and is in a stopped state.

When the exposure is completed, the microcapsule paper 20 is moved to the pressure roller 30a by the driving force of the microcapsule paper feed rollers 23, 23, 23, film feed devices 7.7, 7.7, and take-up roller 27.

It is transported in the direction 30b. On the other hand, the color developing paper 35 is fed one by one by a half-moon roller 41, and is moved to the pressure roller 30a by a paper feed roller 42 and a paper feed guide 43.

30b. And microcapsule paper 20
The exposed surface of the color developer paper 35 and the color developer coated surface of the color developer paper 35 are pressed against each other by pressure rollers 30a and 30b, and the image is transferred onto the color developer paper 35 in a state in which they are superimposed so as to be in contact with each other. Developing paper 35
While being further conveyed by the conveyor belt 52, color development is promoted by the heater 51 of the heat fixing device 50, and the image is output as an image.

The present invention is not limited to the above-described embodiments, and various changes can be made without departing from the spirit thereof. For example, in this embodiment, a color filter is used to create a color liquid crystal exposure device, but the color filter may be omitted and a monochrome liquid crystal exposure device may be used.

〔Effect of the invention〕

As described in detail above, according to the present invention, the photosensitive recording medium
Since the light is exposed through a light diffusion film placed between the CD shutter and the LCD shutter, the non-exposed areas projected by the black mask (unexposed area) of the LCD shutter are removed, making it possible to form high-quality images. Therefore, it is possible to prevent particles on the photosensitive recording medium from adhering to the surface of the LCD shutter, and also to prevent scratches on the surface of the photosensitive recording medium.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of an image recording device using the liquid crystal exposure device of the present invention, Fig. 2 is an external perspective view of main parts of the liquid crystal exposure device shown in Fig. 1, and Fig. 3 is an LCD shutter and light diffusion. FIG. 4 is a schematic side view for explaining the film, and a plan view of essential parts showing the arrangement of liquid crystal light modulation elements. 1... Image recording device, 2... Liquid crystal exposure device, 3...
・/% Rogen lamp, 3a...Reflector, 3b...
・Condenser lens, 4R, 4G, 4B...Filter 5...LCD shutter 5a...Liquid crystal light modulation element, 6...Light diffusion film, 7...Film feeding device, 20...Microcapsule Paper (photosensitive recording medium). Figure Figure Figure Figure Figure

Claims (1)

[Scope of Claims] A liquid crystal exposure device that exposes a photosensitive recording medium based on an image signal, the liquid crystal exposure device including a light source, an LCD shutter comprising a plurality of liquid crystal light modulation elements, and a light-sensitive recording medium connected to the LCD shutter during exposure. a light diffusion film disposed between the light source and the LCD shutter to diffuse the light incident on the LCD shutter; a film feeding device that conveys the light diffusion film at a speed equal to the conveyance speed of the photosensitive recording medium; 1. A liquid crystal exposure device characterized by comprising a condensing means for collimating light.