JPH04147244A - Liquid crystal exposing device - Google Patents

Abstract

PURPOSE:To cast light vertically to a liquid crystal panel and to make image quality clear by turning the light cast to the liquid crystal panel into nearly parallel rays of light. CONSTITUTION:A condenser lens 6 by which the light from a light source 7 is made the parallel rays of light is arranged between a reflection mirror 8 and an LCD panel 5. The lens 6 is in the range of the angle of visual field where the contrast ratio of the LCD panel 5 is not changed so much. After the light from the light source 7 is turned into the parallel rays of light by the lens 6 in such constitution, it is made incident on the shutter 5 and the light transmitted through the shutter is turned into red light by a red filter 9. The parallel rays of light are intercepted by a black mask 5 being a non- exposed part, thereby obtaining the nicely-varied image quality such as the light does not get into just under the black mask 5b even though a plane glass 10 is thick. Exposure concerning green and blue is executed in the same manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal exposure apparatus, and particularly to a liquid crystal exposure apparatus that exposes an LCD panel in close contact with the apparatus.

[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 the alignment film (inner side). 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 Since they are shifted by 90 degrees, the liquid crystal molecules exhibit a twisted structure in the long axis direction of the molecules, 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 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, the polarization direction of the linearly polarized light is rotated by 90 degrees due to the birefringence of the liquid crystal molecules and the above-described 90 degree twisted alignment structure. 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.

Next, a liquid crystal exposure apparatus 100 using the above-mentioned LCD shutter will be explained with reference to FIG. FIG. 7 is a diagram for explaining the liquid crystal exposure apparatus 100, which includes the halogen lamp 10 as a light source as described above.
1. Condenser lens 102, LCD shutter 103,
A color filter 104R that separates the light transmitted through the LCD shutter 103 into a single color of red, green, or blue.

104G, 104B, optical lens 10 as condensing means
5.

Such a liquid crystal exposure apparatus 100 operates as follows.

When the resolution setting key (not shown) is pressed down, the LC
The D shutter 104 is moved to a predetermined position by the shutter drive device, the optical lens 105 is moved to a predetermined focal position by the lens drive device, and the projection range of the LCD shutter 103 is formed by the controller correspondingly.

Next, when a print start key (not shown) is pressed down, the halogen lamp 101 is turned on, and the light from the halogen lamp 101 is converted into parallel light by the condenser lens 102, and then enters the LCD shutter 103. This LCD shutter 103 is controlled by a controller in accordance with a red (R) image signal. Further, a red filter 104R is inserted into the optical path. And the LCD
The light transmitted through the shutter 103 is filtered through a red filter 104R.
The red light is irradiated onto the exposure range 120a on the microcapsule paper 120 through the optical lens 105, and the red exposure is completed. After this, green exposure and blue exposure are performed to form a latent image on the microcapsule paper. An image is formed by pressure developing this onto color developing paper. When the LCD panel 103 is brought into close contact with photosensitive paper for exposure, scattered white light is used.

[Problem to be solved by the invention]

However, as described above, according to the prior art, the photosensitive paper 120 and the LCD panel 103 are used in close contact with each other, and scattered white light is used, so the black mask that separates each pixel of the liquid crystal in the LCD panel is not exposed. For,
There is a problem that the sharpness of the image quality decreases.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a liquid crystal exposure device that can improve image quality by vertically applying light to an LCD panel.

[Means to solve the problem]

The present invention has the above-mentioned objects, and includes a light source having a wavelength necessary for exposing a photosensitive recording medium, a light condensing means for reflecting and utilizing the light from the light source, and a plurality of light sources that can be controlled according to the image to be recorded. In a liquid crystal exposure apparatus equipped with a liquid crystal display panel including a liquid crystal cell, the light applied to the liquid crystal display panel is substantially parallel light.

[Effect]

Therefore, by attaching a reflective mirror/condenser lens to the light source to create parallel light, and then shining the parallel light onto the LCD panel, the image of the black mask will appear as it is on the photosensitive paper, but the image itself will be clear. .

Furthermore, the spectral characteristics of the light source are such that a light source with three wavelengths of R, G, and B that matches the characteristics of the photosensitive paper allows the use of inexpensive color filters with a wide wavelength band and enables highly efficient exposure.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal exposure apparatus of the present invention will be explained below based on illustrated embodiments.

First, referring to FIG. 1, a schematic configuration diagram of a liquid crystal exposure apparatus is shown. In the liquid crystal exposure device, an LCD panel 5 is placed on a photosensitive paper 1 in close contact with it.

On the other hand, a reflecting mirror 8 is arranged to irradiate light onto the photosensitive paper 1. Further, a condenser lens 6 is arranged between the reflection mirror 8 and the LCD panel 5 to convert the light from the light source 7 into parallel light. As shown in FIG. 5, the LCD panel 5 is shielded from light by a liquid crystal light modulation element (liquid crystal pixel) 5a and a black mask 5b placed around each liquid crystal pixel 5a to prevent leakage current.

Next, the condenser lens 6 will be explained.

According to the condenser lens 6, the contrast ratio of the LCD panel 5 is made to fall within the viewing angle range (00 to -θ0) where it does not change much (m-n). Referring to FIG. 3, the contrast ratio is plotted on the vertical axis and the viewing angle is plotted on the horizontal axis, and is expressed as a curve. Assuming that the angle within the viewing angle range in which the contrast ratio does not change much, that is, the foot contrast ratio, is between m and n, the corresponding viewing angle range (-θ0 to +00) can be found. Then, a condenser lens 6 that provides such a viewing angle range (-60 to 10 θ0) is selected. This condenser lens 6 allows the light reflected by the reflection mirror 8 that reflects the light from the light source 7 to be reflected within a viewing angle range (-θ0 to +00).
It is considered to be light that is close to parallel light within the range.

In FIG. 4, parallel light P passes through a flat glass 10 within a viewing angle range (60 to -θ0) and is incident on a black mask 5b arranged around a liquid crystal pixel 5a. The light incident on the black mask 5b in the flat glass 10 is tilted only in the viewing angle range (00 to -00), parallel light is blocked by the black mask 5b which is the non-exposed part, and the thickness of the flat glass 10 is However, the light is blocked by the black mask 2. That is, even if the flat glass 10 is thick, light does not penetrate directly below the black mask.

Here, the light source 7 has a color spectrum as shown in FIG. That is, it has a sharp light amount for RGB.

Next, the operation of the liquid crystal exposure apparatus will be explained.

First, when a print start key (not shown) is pressed down, the light from the halogen lamp 7 is converted into parallel light by the condenser lens 6, and then enters the LCD shutter 5. This LCD shutter 5 is controlled by a controller (not shown) in accordance with a red (R) image signal. The light transmitted through the LCD shutter 5 is turned into red light by a red filter 9. The parallel light is blocked by the black mask 5b, which is a non-exposed part, and even if the flat glass 10 is thick, a sharp image quality is obtained in which the light does not penetrate directly below the black mask 5b, and the red exposure is completed. Next, green exposure is performed using the green filter 5G in accordance with the green (G) image signal. Similarly, blue exposure is performed using the blue filter 5B according to the blue (B) image signal. As a result, the microcapsule paper 20 stops being conveyed and is in a stopped state.

Next, the microcapsule paper 20 is moved to the pressure roller 30a by the driving force of the feed roller 23 and the take-up roller 27.
, 30b. On the other hand, the developer paper 35 is fed one by one by a half-moon roller 41, and is conveyed to pressure rollers 30a and 30b by a paper feed roller 42 and a paper feed guide 43. Then, the exposed surface of the microcapsule paper 20 and the developer-coated surface of the color developer paper 35 are pressed against each other by pressure rollers 30a and 30b in a state where they are superimposed so as to be in contact with each other, and the image is transferred to the color developer paper 35. The color developing paper 35 is further conveyed by a conveyor belt 52 while being accelerated in color development by a heater 51 of a heat fixing device 50, and is output as an image.

〔Effect of the invention〕

According to the present invention, sharper image quality can be obtained by using parallel light in close exposure between an LCD panel and photosensitive paper, and by using an RGB three-wavelength spectrum light source as a light source, an inexpensive wavelength band can be obtained. A wide range of color filters can be used, and exposure can be performed with high efficiency.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a liquid crystal exposure device of the present invention, FIG. 2 is a partially enlarged view of the liquid crystal exposure device of the present invention, and FIG. 3 is a graph showing the relationship between contrast ratio and viewing angle. Fourth
The figure is a cross-sectional view showing the optical path between the LCD panel and photosensitive paper.
The figure is an enlarged view of the LCD panel, Figure 6 is a graph showing the wavelength and light amount of the light source, Figure 7 is a schematic configuration diagram of a conventional liquid crystal exposure device, and Figure 8 is a plane view of conventional photosensitive paper. FIG. 3 is a cross-sectional view showing the relationship with glass. 1... Photosensitive paper, 2... Black mask, 3... Liquid crystal, 4... Flat glass, 5... LCD panel, 6...
・Condenser lens, 7...Light source, 8...Reflection mirror Applicant's agent Yasushi Ishikawa Figure 4 Figure 4 Chairman's funeral diagram Figure 8

Claims (1)

[Claims] A liquid crystal display panel consisting of a light source with a wavelength necessary for exposing a photosensitive recording medium, a condensing means for reflecting and utilizing the light from the light source, and a plurality of liquid crystal cells that can be controlled according to the image to be recorded. What is claimed is: 1. A liquid crystal exposure device comprising: a liquid crystal exposure device in which light applied to a liquid crystal display panel is substantially parallel light;