JPS63109069A - Liquid-crystal printer device - Google Patents

Abstract

PURPOSE:To provide a liquid-crystal shutter capable of securely reproducing intermediate tones, by controlling the opening and closing of each liquid-crystal shutter according to an image density signal corresponding to the shutter. CONSTITUTION:Groups of a plurality of liquid-crystal shutters 1 arranged in a lateral row in the axial direction of a photosensitive drum 14 are arranged in vertical rows in the rotating direction of the body 14. Filter rows 3 differing in the quantity of light transmitted therethrough are provided one for each of the lateral rows, and each of the liquid-crystal shutters is opened and closed under control according to an image density signal corresponding thereto, whereby the filters are operated on a selected combination basis to reproduce an intermediate tone. A latent image formed on the photosensitive body 14 by the opening and closing of the liquid-crystal shutters is subjected to developing, transferring and fixing processes, whereby a developed image is formed, and a developing agent left on the body 14 is cleaned up by a cleaner part. The potential of the latent image on the photosensitive body is varied through the filers differing in the quantity of light transmitted therethrough at the time of opening the shutter, thereby producing gradation properties.

Description

Detailed Description of the Invention A. Object of the Invention [Field of Industrial Application] The present invention relates to a liquid crystal printer device using an electrophotographic process using a liquid crystal head consisting of a liquid crystal shutter, a liquid crystal shutter drive circuit, and an optical fiber bundle. .

[Conventional technology]

photoreceptor section, developing section, fixing section, charging section, fist cleaner section, etc.
2. Description of the Related Art As a printer using an electrophotographic process, a liquid crystal printer using a liquid crystal head consisting of a liquid crystal shutter and its drive control means is known.

When using a nematic liquid crystal as a shutter, the shutter is opened and closed according to the image density electrical signal (digital signal).For example, to change the liquid crystal display (nematic liquid crystal) from the open state to the closed state, is 20
A voltage of ~24V needs to be applied; anything less than that will result in unstable operation.

In addition, since the Nyatta is either open or closed, allowing light to pass through it or not, the WI image potential V on the photoreceptor forms only two areas: a bright area and a dark area.
It has the disadvantage of not being able to reproduce halftones. FIG. 5 shows the relationship between the photoreceptor potential V and the zero image source degree, which indicates bright and dark areas depending on the opening and closing of the liquid crystal shutter, and shows that intermediate tones cannot be expressed.

Therefore, as a way to reproduce the midtones, the conventional Nyatta open time! Attempts have been made to adjust the iJ. In other words, by shortening the opening time, it is possible to improve the optical quality.

This is an attempt to create a midtone by reducing the .

[Problem that the invention seeks to solve]

However, when a nematic liquid crystal is used, the shutter transition from a closed state to an open state is unstable, and it takes time to reach a 100% open state.

Since there is not sufficient h-reliability for the digital signal to always rise in a constant manner, if it is desired to increase the number of gradations, it becomes difficult to reproduce halftones depending on the time of the applied voltage. Figure 6 explains the above relationship, and shows that when the 24 V signal is applied to the shutter, it closes, and when Ov it opens, and it takes time to go from closed to open, and the progress from the closed state to the open state is also stable. It means that it is not.

In view of the above drawbacks, an object of the present invention is to provide a liquid crystal shutter that can reliably reproduce halftones.

Summary: Structure of the Invention [Means for Solving Problems] The present invention provides a liquid crystal printer device using an electrophotographic printer, in which a plurality of liquid crystal shutter groups are arranged horizontally in a row in the axial direction of a photoreceptor at equal intervals. However, a plurality of rows are arranged vertically in the direction of rotation of the photoreceptor at the same interval, and filters with different amounts of transmitted light are provided in each horizontal row of the liquid crystal shutter group in close contact with the liquid crystal shutter group, and each individual liquid crystal shutter is This is a liquid crystal pre/representation device characterized in that the filters are configured to act in selective combinations by controlling opening and closing using image density signals.

[For production]

A plurality of liquid crystal shutter groups are arranged horizontally in a row in the axial direction of the photoconductor, and multiple rows are arranged vertically in the rotational direction of the photoconductor, and a filter row with a different amount of transmitted light is provided for each horizontal row. By controlling the opening and closing of the liquid crystal shutters using corresponding image density signals, the filters act in a selective combination to reproduce halftones.

〔Example〕

FIG. 1 is a schematic diagram illustrating the structure of a liquid crystal cell according to the present invention, and FIG. 2 shows an embodiment of a printer using the liquid crystal cell described above.

For example, l indicates a 90x90μm liquid crystal shutter, and 10
They are arranged vertically (in the rotational direction of the photoconductor 14) and horizontally (in the axial direction of the photoconductor) at intervals of ILm. 2 is a cell in which the liquid crystal shutter is incorporated; 3 is four filters that have different amounts of transmitted light and are closely spaced in the horizontal direction in which the shutters are lined up; 4 is a wiring circuit; 5 is a socket; 6 is a liquid crystal shutter. A drive circuit, 7 a drive power source, 8 a box containing the optical fiber bundle 11 and the above-mentioned liquid crystal cell, 9 a liquid crystal cell fixing member, 10 a printer body frame material, 12 a member for fixing the fiber bundle, and 13 a cell. A fox lens, 15 is a light source, and 16 is a reflecting plate. Transparent electrodes sandwiching the liquid crystal, polarizing glass, etc. are omitted from the figure.

The latent image formed on the photoconductor 14 by opening and closing the liquid crystal shutter undergoes a development, transfer, and fixing process (not shown in the figure) to form a visible image, and the developer left on the photoconductor 14 is removed by a cleaner section. Cleaned.

The present invention provides gradation by changing the Wr image potential of the photoreceptor through filters with different amounts of transmitted light when the shutter is open, and in the embodiments shown in FIGS. In other words, four types of filters A to D having different amounts of transmitted light are used for four liquid crystal shutters A to D. When light is incident on the shutters of each row A and BΦCφD, filter a is a transparent filter, and when the shutter is open, the photoreceptor potential is ■. ~
The range of V1 is 1-image density Do (white) (see the relationship diagram between image density and photoreceptor potential V in the fourth drawing), and the photoreceptor potential is v1 to v2 (b ), V2
˜V3 (C), V3˜Va (d), and the image density is −D2·D3. Further, the image density D4 is solid black, and when both shutters are closed, the photoreceptor potential is ~4.

Therefore, for example, the operating state of the Nyatta when obtaining each image density is as follows.

Image density D4 (peta black): Shear 2ta A-B-C-
D all closed image density Ds: All B1 IC closed, D open image density D2
:A*B closed, C open, D can be open or closed.

Image density: A closed, B open, CD may be open or closed.

Image density DO: A open, B and CD may be open or closed.

Each liquid crystal shutter 1 is controlled by an image electric signal so that the above relationship is established.

In the above example, the distance between the shutter centers is 1100
Since it is 1L, it is necessary to synchronize the photoconductor rotation speed and the shutter opening/closing.For example, the photoconductor rotation speed is 50+s.
At /+ec, the shutters in the adjacent row are driven. Therefore, there is a difference of 3 m5ec in the opening/closing time between rows A and D.

In this example, the resolution is equivalent to 10 pa+, but by changing the size of the shutter, the resolution can be increased to 4 to 3 (
Up to l pel phase 8 is possible. Other conditions such as photoreceptor rotation speed (process speed) and filter width (
For example, aebsc*d groan aed*b*c, d@c*b*
a, d*b*c*a-7) may be changed, and furthermore, by changing the number of filters, the number of gradations can be arbitrarily set to three or more gradations. Furthermore, the present invention can be applied to ferroelectric liquid crystals other than nematic liquid crystals.

C. Effects of the Invention With the above configuration, the liquid crystal shutter can obtain three or more gradations, and is therefore extremely useful as a liquid crystal printer device that reliably reproduces halftones.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of the liquid crystal cell of the present invention, FIG. 2 is a schematic diagram of a printer using the liquid crystal cell, FIG. 3 is an enlarged side view showing the arrangement of the liquid crystal shutter rows and filter rows, and FIG. FIG. 5 is a diagram showing the relationship between image density and photoreceptor potential, and FIG. 6 is an explanatory diagram of the conventional halftone reproduction method of a liquid crystal shutter. DESCRIPTION OF SYMBOLS 1...Liquid crystal shutter, 2...Cell in which the liquid crystal shutter is incorporated, 3...A filter attached to the shutter, 4...Wiring circuit, 5...Socket, 6...Shutter drive Circuit, 7... Drive power supply, 8... Printer head box, 10... Printer body frame material, 11...
- Optical fiber bundle, 12...Fiber bundle fixing member, 13
... Selfox lens, 14 ... Photoreceptor, 15
...Light source, 16...Reflector.

Claims (1)

[Claims] (1) In a liquid crystal printer device using an electrophotographic printer, a plurality of liquid crystal shutter groups are arranged horizontally in a row in the direction of the axis of the photoreceptor at equal intervals, and multiple rows of liquid crystal shutters are arranged vertically in the direction of rotation of the photoreceptor at the same intervals. , a filter with a different amount of transmitted light is provided in each horizontal row of the liquid crystal shutter group in close contact with the liquid crystal shutter group, and the opening and closing of each individual liquid crystal shutter is controlled by the image density signal corresponding to the filter, so that the filters can be selectively combined. What is claimed is: 1. A liquid crystal printer device characterized in that it is configured to act as a liquid crystal printer.