JPH03102992A - Color video printer - Google Patents

Abstract

PURPOSE:To form a recorded image free from fogging and having high saturation by only one exposure by forming a light mixing layer consisting of a rugged transparent member on one main face of a transparent base. CONSTITUTION:Incident light 22 from one main face side of a color liquid crystal panel 20 is modulated at its brightness in accordance with the density component of a video signal and the modulated light is projected from the other main face, passed through a glass base 14 and made incident upon the light mixing layer 16. The layer 16 consists of many light mixing blocks 17 covering three picture element areas R, G, B of a color filter 10, red light 22R, green light 22G and blue right 22B made incident upon the same block 17 through the filter 10 are mixed to expose a photosensitive material. Thereby, the superposed exposure of black color corresponding to the frame of the color filters on the R, G, B light components can be prevented and the saturation of respective colors can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to video blinking, particularly to a color video printer for forming a hard copy of a visible image from a color video signal.

For example, many video printers that record visible images on photosensitive materials have complicated processes. A pending patent application filed by the present applicant, Japanese Patent Application No. 1-73929, describes a device that receives a video signal, drives a liquid crystal panel, exposes a visible image to a photosensitive material that is in close contact with the liquid crystal panel, and obtains a print. Are listed. This device is compact and suitable for consumer use.

However, this device displays images of each color component on a black-and-white liquid panel using video signals separated into three primary colors, and these images are exposed to the photosensitive material three times in total, making the exposure process complicated. Therefore, in order to simplify the exposure process, it is conceivable to display a color image on a color liquid crystal panel with color filters arranged on the surface of the liquid crystal panel, and then expose the photosensitive material to this image. However, in this case, the image becomes blurred when exposed with a diffuse backlight. To prevent this, when exposure is performed using white light, for example, the light that has passed through each component pixel of the liquid crystal panel exposes the photosensitive material at the same intervals, forming an array of dots. Additionally, a black frame around the pixels of the color LCD panel remains between these pixels. Therefore, in the developed photosensitive material, the portion that should be white is mixed with black in the RGB three-color dots, and when viewed with the naked eye, it appears gray, causing a problem of large force blur. There is also the problem of poor color saturation.

It is an object of the present invention to improve the problems of the prior art and to provide a color bidet printer that can produce recorded images with no fog and high chroma with a single exposure.

According to the present invention, a color video is provided which receives a video signal representing a color image, displays the color image on a color liquid crystal panel, and records the displayed color image on a color photosensitive recording medium as a visible image. In a printer, a color liquid panel consists of two transparent substrates having driving electrodes, a liquid crystal layer that is laminated between the two transparent substrates, and is driven according to a video signal to display a color image, and a transparent substrate. It has a color filter that is laminated on one main surface and allows light of each color component to pass through, and a light mixing layer that is adhered to one main surface of a transparent substrate. The device mixes light of each color component that has passed through a color filter, a liquid crystal layer, and a transparent substrate. by this. A recorded image with high color saturation can be obtained.

DESCRIPTION OF THE EMBODIMENTS One embodiment of a color video printer according to the present invention will now be described in detail with reference to the accompanying drawings.

Referring to FIG. 1, a schematic cross-sectional view of a color liquid crystal panel used in a printer according to the present invention is shown. In the color liquid crystal panel 20, glass substrates 14 and l5 are laminated on both sides of the laminated color filter IO and liquid crystal layer l2, respectively, and a light mixing layer l6 is laminated on the other main surface of the glass substrate 14. That is, a color filter IO and a light mixing layer 16 are laminated on a black and white liquid crystal panel. This color liquid crystal panel 20 is brought into close contact with the photosensitive material 18 to display a visible image based on a video signal, and the color image is recorded on the photosensitive material I8 by exposure and development.

Glass substrates l4 and l5 used in the color liquid crystal panel 20 are transparent substrates for supporting the liquid crystal layer 12, the color filter 10, and the light mixing layer I6, and are laminated to sandwich the color filter IO and the liquid crystal layer 12. . Note that other transparent members such as plastic may be used in place of the glass substrate l4.

The color filter layer IO includes a large number of three types of color filter elements of three primary colors RGH arranged two-dimensionally in a rectangular matrix array, for example. Color filter IO
is the R. of the white parallel light 22 that has passed through the glass substrate l5. G.
The B color components are passed through and incident on the liquid crystal layer I2 as red, green, and blue light 22, respectively.

In the liquid crystal layer l2, a large number of liquid crystal display elements are two-dimensionally arranged so as to correspond to the positions of the matrix array of elements of the color filter lO.

The liquid crystal layer l2 is an image visualization device that displays a color image according to the arrangement of the color filters IO when driven according to a video signal. The liquid crystal layer 12 has transparent electrodes (not shown) on both main surfaces thereof. The transparent electrode includes a common electrode and a plurality of drive electrodes connected to switching elements such as transistors (not shown), and has a structure in which the liquid crystal is sandwiched between them. For example, when a signal voltage is applied to the gate electrode of a transistor, the connection between the source and train electrodes of the transistor changes from a cutoff state to a conduction state, and a drive voltage is applied to the drive electrode, which changes the alignment of liquid crystal molecules (not shown) in the liquid crystal layer 12. By changing the transmittance of the light 22, the transmittance of the light 22 is changed. Therefore, the light 22 that enters from one main surface II1 of the color liquid crystal panel 20 is luminance-modulated according to the density component of the video signal, is emitted from the other main surface, passes through the glass substrate l4,
The light is incident on the light mixing layer l6.

The light mixing layer 16 has one main surface a that is generally flat and has fine irregularities, and the other main surface b that is smooth and convex, and is made up of a plurality of light mixing blocks I7. The light mixing layer l6 includes at least R, G. It is a relief-like layer in which a large number of light mixing blocks 17 covering an area of three pixels (one unit) consisting of B are arranged.

The optical mixing layer 16 will be explained in more detail. The R. G. Irregularities smaller than the width of B are formed, and the incident light 22 is scattered by the recesses and recesses. On the other hand, the vicinity of the main surface b of the light mixing block l7 has a convex lens function due to its shape.

In other words, the light mixing block 17 can be considered to be a combination of a light diffusing section and a plano-convex lens.

Therefore, for example, among the white parallel light 22 incident on the liquid crystal panel 20, the light 22 along the optical axis 22R is filtered through the color filter l.
Passing through the R part of O, only the red light 22R enters the light mixing layer l6
is incident on . The incident red light 22R is diffused near the main surface a and converged near the main surface b. As a result, the red light 22R is diffused to about the size of the light mixing block 17, and the photosensitive material below it is exposed to about the size of the light mixing block 17. White light 2 passing through optical axes 22G and 22B
2 is also filtered by color filter IO respectively, and green light 22
The light becomes G and blue light 22B and enters the light mixing layer l6. The green light 22G i5 and the blue light 22B incident on the light mixing layer 16 are irradiated to the same area as the red light 22R by the light mixing block 17, so that the three primary color components RGB are mixed and exposed to the photosensitive material as white light 22. Ru.

Due to these things, R. G. B passing light 22R.
22G. The photosensitive material 18 can be exposed to white light mixed with 22B. Therefore R,G. Since the black color of the color filter frame can be prevented from being exposed to the B component light, the saturation of each color can be improved. Also R. G. Since the three B color areas are mixed within one pixel, the resolution of the recorded image does not decrease. The thickness of the light mixing block l7 is determined by the degree of unevenness of the main surface a of the light mixing block l7, and the degree of unevenness of the main surface b of the light mixing block l7.
It may be set in relation to the radius of curvature of the light mixing block 17 and the refractive index of the light mixing block 17.

Note that the refractive index of the space formed by the glass substrate l4 does not have to be equal to the refractive index of the optical mixing layer l6. This means that if the refractive index is equal, the incident light 2 is near the main surface a of the light mixing block l7.
This is because the transmitted light 22 travels almost straight without scattering and converges in the vicinity of the main surface b, so that the transmitted light 22 is irradiated onto the photosensitive material 18 unevenly, and the light is hardly mixed.

The photosensitive material 18 may be, for example, an instant photographic material, a normal color photographic paper, or a heat-developable silver salt photosensitive material, but it is preferable to use a negative type photosensitive material. In the figure, for the sake of explanation, the photosensitive material 18 and the optical mixing layer 16 are separated, but in reality they are in close contact with each other.

FIG. 2 is a schematic block diagram of one embodiment of a video printer according to the present invention. The video printer of this embodiment is a color image recording device that receives a color video signal at an input terminal 24 and records the color image represented by the signal as a hard copy on a photosensitive material 18. This device basically consists of a light source 26
, a liquid crystal panel 20, a developing roller 28, an operation display section 30, and a control circuit 40.

The light source 26 is preferably a white parallel light 22 because diffused light lowers the resolution of the recorded image. The light source 26 is a white light 2
The 6 light sources 26, which are light sources for emitting light 2 and are driven by the light source drive circuit 44, emit light 2 from a halogen lamp, for example.
2 may be reflected by the paraboloid of revolution 32. The parallel light 22 from the light source 26 perpendicularly illuminates the main surface of the color filter IO of the liquid crystal panel 20. The amount of light from the light source 26 is the same as the photosensitive material l8.
related to the amount of exposure.

The video signal input terminal 24 is connected to a video signal circuit 34. The video signal input to the input terminal 24 may be in the form of a TV signal or an electronic still camera signal, for example. The video signal circuit 34 is a signal processing circuit that converts a video signal in such a signal format into digital data of three primary color components RGB. Its output 36 is a frame memory 38
is input. Note that the video signal input to the input terminal 24 may be in the form of a three primary color signal RGH, or may be such a type of digital data. In the latter case, the video signal circuit 34 is unnecessary.

The frame memory 38 is a storage circuit that stores one frame of such RGB component data. The reading and writing of the frame memory 38 is controlled by a control circuit 40, and its read data output is connected to a liquid crystal panel drive circuit 42. The drive circuit 42 drives the individual pixel cells of the liquid crystal panel 20 in a field-sequential manner according to the three primary color component data read out from the frame memory 38. The control circuit 40 is a functional unit that unifies and controls the operation of the entire device. ．． An operation display section 30 is connected to the control circuit 40, which allows the operator to input instructions manually and to display the status of the apparatus to the operator.

Next, the operation will be explained.

For example, the output of a video signal source such as an electronic still camera is connected to the video signal input terminal 24. When the operation display section 30 is operated to instruct the reading of a video signal, the control circuit 40 controls the video signal circuit 34 and the frame memory 38 through the control lines 48i3 and 50, respectively (BL and L, input to the input terminal 24). The video signal circuit 34 converts this into digital data in a predetermined format, for example, RGB color component signals.The converted color component signals are stored in the frame memory 38.

When the operation display unit 30 is operated to input an image recording instruction, the control circuit 40 responds to this and first displays the liquid crystal panel 2.
0 and visualize the color image.

In synchronization with driving the liquid crystal panel 20, the control circuit 40 controls the light source drive circuit 44 to cause the light source 26 to emit light for a predetermined period of time. A color image is thereby recorded as a latent image on the photosensitive material 18.

What is important here is that since the color filter lO and the light mixing layer l6 are laminated on the liquid crystal panel, by bringing them into close contact with the photosensitive material l8 and exposing them to white parallel light 22, at least one unit of the liquid crystal panel 20 can be The passing light 22 is mixed uniformly in each light mixing layer l6 in the area of the pixel, so that, for example, white areas of the visible image are recorded as white instead of gray, making it possible to obtain a sharp and highly saturated image. It is.

After recording the latent image, the control circuit 40 controls the developing roller drive circuit 46 to drive the developing roller 28. As a result, the recorded photosensitive material l8 is transferred to the developing roller 28.
The image is developed or fixed and discharged.

FIG. 3 shows another embodiment of the liquid crystal panel 20. Color filter IO, liquid crystal layer I2 and glass substrate 14. Is is laminated, and a spreading plate 5 is placed on the glass substrate l4.
2 are stacked. The diffuser plate 52 is a glass substrate 14.
Light 22 transmitted through color filter lO and liquid crystal layer l2
It has a lenticular shape with fine irregularities laminated on the main surface C on the incident side, and the main surface d through which the light 22 passes is smooth and transparent. The diffuser plate 52 is not divided like the light mixing block 17 in FIG. 1, and is a cloudy glass-like layer that appears to be substantially plate-like. The main surface C of the diffusion plate 52 is attached to the glass substrate l4, and diffuses the white parallel light 22 from the light source 26 in the vicinity of the main surface C in the same manner as described above. As shown in the figure, the beams 22 of mutually different optical axes are diffused. As a result, the light 22 incident on the diffusion plate 52 is mixed. However, since there is no part corresponding to a convex lens like the light mixing block l7 in the panel of FIG. 1, the light 22 is refracted near the main surface d and further diverged to the outside of the pixel area. As a result, the resolution of the recorded image decreases a little, but the saturation is as good as above,
For example, white parts are exposed to white light.

Further, in this embodiment, the color filter 10 is a liquid crystal layer l.
Although the filter IO and the glass substrate 15 are laminated between each other, the positions of the filter IO and the glass substrate 15 may be reversed.

As described above, the color video printer according to the present invention uses a color liquid crystal panel to mix the three colors of RGB light of a visible image pixel by pixel and exposes the photosensitive material, so that each color component light is distributed in a predetermined area of the photosensitive material. can be mixed and overlapping irradiation. Therefore, the white part becomes white, and a visible image with good color saturation can be obtained. Further, the color video printer according to the present invention has a simple structure and can record a color visible image on a photosensitive material by one exposure.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of a color liquid crystal panel used in a color video printer according to the present invention, FIG. 2 is a block diagram showing a schematic configuration of a color video printer according to the present invention, and FIG. 3 is a cross-sectional view of an embodiment of a color liquid crystal panel used in a color video printer according to the present invention. FIG. 3 is a cross-sectional view of another embodiment of a color liquid crystal panel used in a color video printer. Description of main parts Color filter Liquid crystal layer Glass substrate Light mixing layer Light mixing block No. 1 Figure 22 Photosensitive material Liquid crystal panel Light diffusion plate

Claims (1)

[Scope of Claims] A color video printer that receives a video signal representing a color image, displays the color image on a color liquid crystal panel, and records the displayed color image on a color photosensitive recording medium as a visible image. The color liquid crystal panel includes: two transparent substrates having drive electrodes; a liquid crystal layer laminated between the two transparent substrates and driven according to the video signal to display the color image; and the transparent substrate. a color filter that is laminated on one main surface of the transparent substrate to allow light of each color component to pass; and a light mixing layer that is adhered to one main surface of the transparent substrate, and one main surface of the light mixing layer is uneven. 1. A color video printer, comprising a transparent member, and mixing light of each color component that has passed through the color filter, the liquid crystal layer, and the transparent substrate.