JPH04248533A - Image recorder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus.

0002

2. Description of the Related Art Conventionally, various image recording apparatuses have been proposed in which light from a light source passes through a liquid crystal panel (hereinafter referred to as LCD) and the transmitted light is exposed and recorded on a photosensitive medium.

[0003] LCDs include those of a simple matrix type represented by a super twisted nematic type (STN type) and an active matrix type represented by a thin film transistor type (TFT type). Although a detailed explanation of these will be omitted, the following points are major differences.

[0004] STN type LCDs have a slow response speed, but are superior in cost because of their simple structure.

On the other hand, TFT type LCDs have a fast response speed, but because each pixel requires a transistor, they are large in size and have a complicated structure, which results in poor yields and makes it extremely difficult to reduce costs.

[0006] Since response speed is not a particular problem for LCDs in image recording devices, S
The TN method is often used. However, when comparing the contrast ratio of the two, the TFT method is about 100:1, while the STN method is about 10:1, which is a very low value, and this difference in contrast ratio is the difference in the output image. affect the contrast. In other words, in an image recording apparatus using an STN type LCD, the contrast of the output image becomes low.

[0007]

[Problems to be Solved by the Invention] The present invention has been made to solve the above-mentioned problems.
An object of the present invention is to provide an image recording device that realizes high-contrast image output even when using an N-type LCD.

[0008]

SUMMARY OF THE INVENTION In order to achieve this object, the image recording apparatus of the present invention includes a light source and an LCD group formed by stacking a plurality of LCDs.

[0009]

[Operation] In the image recording apparatus of the present invention having the above structure, light from a light source is passed through the LCD group, and the transmitted light is exposed and recorded on a photosensitive medium.

0010

Embodiments Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

This liquid crystal printer 1 uses a photosensitive recording medium consisting of microcapsule paper 7 and developer paper 8, which will be described later, which are photosensitive and pressure sensitive papers.

Microcapsules are coated on the surface of the support of the microcapsule paper 7 used in this example, and the microcapsules contain a dye precursor that reacts with a color developer. There is. A color developer is coated on the surface of the support of the color developer paper 8 and develops color by reacting with a dye precursor, but the details are described in U.S. Pat. No. 4,399,209, etc., and are omitted here. do.

A halogen lamp 3 is used as an exposure light source, and a reflector 2 is placed above it. Further, a condenser lens 4 is arranged below the halogen lamp 3, and an infrared cut filter 5 is further arranged below it. Below the infrared cut filter 5, a filter unit 22 consisting of color filters 22R, 22G, and 22B and an LCD group 6 are arranged.

As shown in FIG. 1, the LCD group 6 includes two STNs.
The system consists of LCDs 6a and 6b, and each LCD
6a and 6b are attached so that the positions of their corresponding pixels coincide with each other. At this time, each LCD6a, 6
It is necessary to pay attention to the orientation of the polarizing plates b, and the opposing polarizing plates 60a and 60b must be oriented in the same direction. Further, these two polarizing plates may be replaced with one polarizing plate.

The light-shielding cartridge 18 contains unexposed microcapsule paper 7 wound around the cartridge shaft 15. A feed roller 19 is disposed on the right side of the cartridge 18, and the feed roller 19 transports the microcapsule paper 7 in the direction of the LCD group 6, and exposes the microcapsule paper 7 while stationary below the LCD group 6. An image is formed. Further, the microcapsule paper 7 passes between a pair of pressure rollers 11a and 11b, and is wound around a winding shaft 16.

A half-moon roller 9 is disposed above the developing paper 8, and a paper feed roller 10 and a paper feed guide 17 are disposed on the left side. Further, a heat fixing device 12 is provided below the color developer paper 8, and a heater 13 is provided inside the heat fixing device 12, and a conveyor belt 14 is provided below.

Next, the operation of the liquid crystal printer 1 will be explained.

First, when a print start key (not shown) is pressed, the same image is displayed on each of the LCDs 6a and 6b in response to image signals input to the LCD group 6 from the outside. Next, the halogen lamp 3, which is the light source, is turned on,
The light from the halogen lamp 3 is efficiently condensed by the reflector 2 and the condensing lens 4, made into a substantially parallel beam, and irradiated onto the LCD group 6 via the infrared cut filter 5 and the red filter 22R.

The stationary microcapsule paper 7 is exposed to light selected by the LCD group 6, which is controlled in accordance with the red signal of the image to be recorded. When the red exposure is completed, the red filter 22R is replaced with the green filter 22G,
The red signal of the LCD group 6 is switched to a green signal and exposed in the same manner. The same applies to blue, and the halogen lamp 3 is turned off after three exposures are completed. In this way, a color latent image is formed on the microcapsule paper 7. Next, the microcapsule paper 7 is sent toward the pressure rollers 11a and 11b by the driving force of the take-up roller 16 and the feed roller 19.

On the other hand, the developing paper 8 is fed one by one by a half-moon roller 9, passes through a paper feed guide 17, and is sent by a paper feed roller 10 to pressure rollers 11a, b. The exposed surface of the microcapsule paper 7 and the developer-coated surface of the color developer paper 8 are pressed by pressure rollers 11a and 11b in a state where they face each other, and the image is transferred to the color developer paper 8. Further, color development of the color developing paper 8 is promoted by a heat fixing device 12 having a heater 13 while being further conveyed by a conveyor belt 14, and outputted as an image.

In the above image recording process, the LCD 6a
and LCD6b have exactly the same cells that block light when it passes through, so for example, if the contrast ratio of both LCDs is set to 1,
If the ratio is 0:1, a contrast ratio of 100:1 can be obtained when two sheets are stacked. In other words, it is possible to obtain a contrast ratio comparable to that of the TFT method.

As is clear from the above detailed description, according to the liquid crystal printer of this embodiment, a high-contrast image can be obtained even when using a low-cost, low-contrast LCD such as an STN system. .

It should be noted that the present invention is not limited to the embodiments described in detail above, and modifications can be made without departing from the spirit thereof.

[0024]

[Effects of the Invention] As is clear from the above detailed description, according to the image recording device of the present invention, a high contrast image can be obtained even when using a low cost, low contrast LCD such as an STN type LCD. Can be done.

[Brief explanation of the drawing]

FIG. 1 is an enlarged perspective view of an LCD group.

FIG. 2 is an overall configuration diagram of a liquid crystal printer.

[Explanation of symbols]

1. LCD printer 3. Halogen lamp 6 LCD group 7 Microcapsule paper

Claims (1)

[Claims] [Claim 1] A light source and an LCD group configured by stacking a plurality of LCDs, wherein light from the light source is transmitted to the LCD.
An image recording apparatus characterized in that the transmitted light is exposed and recorded on a photosensitive medium.