JPH0478820A - Formation of optical shutter for information output device - Google Patents

Abstract

PURPOSE:To attain fine interelectrode spacings by forming at least one electrode on a pair of light transparent substrates to prescribed patterns by excimer laser processing. CONSTITUTION:This information output device is constituted by providing the liquid crystal electrooptical device which includes the liquid crystal exhibiting a ferroelectric property in a liquid crystal cell provided with a 1st substrate consisting of one piece of electrode consisting of a light transparent conductive material and leads on a light transparent substrate (for example, a 1st substrate having an SiO2 film of 1,000Angstrom thickness) on soda lime glass of 1.1mm thickness and a 2nd substrate consisting of plural pieces of electrodes consisting of a light transparent conductive material and leads on a light transparent substrate, includes the liquid crystal having an ester bond in the main skeleton and has means for arraying the liquid crystal compsn. in a specified direction between the photosensitive drum and the light source. ITO is directly worked at least once by using the excimer laser at the time of working the shapes of the electrodes on the 1st substrate and 2nd substrate of this liquid crystal cell.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to a printer that outputs information from a computer, word processor, etc., an output portion of a facsimile,
The purpose of the present invention is to propose a method for improving a device used in the printing part of a copy machine.

[Conventional technology]

Conventional information output devices have a line-shaped resistance heating section.

Alternatively, there is a thermal head type that transfers dots and outputs two characters or figures by bringing the printing head arranged in a matrix into contact with thermal paper and causing it to change its quality due to heat.Also, there is a thermal head type that outputs two characters or figures by contacting the thermal paper with a print head arranged in a matrix shape, and a heat source is placed closely on a part of the container filled with ink. A type of ink that instantly boils a portion of the ink inside the container and sprays the ink onto the paper that is being transferred from a nozzle attached to the container has been realized.

Furthermore, as a method using a photosensitive drum, a system has been realized in which the output light of a semiconductor laser is point-irradiated onto the drum by rotating a Coriolis mirror, and characters and figures are output by continuous operation.

A method using a line-shaped liquid crystal cell of the guest-host type has become a reality, and the light from the rear illumination of a fluorescent lamp is used as line tod information to irradiate a line onto a photosensitive drum, and the continuous operation of the light irradiates the photosensitive drum to output characters and figures.

In recent years, a method has also been proposed in which a ferroelectric liquid crystal cell is used instead of this guest-host type liquid crystal cell.

[The problem that the invention attempts to solve]

The thermal head and inkjet method described in the conventional technology section have a printing speed of 6000 yen per second due to the limit of response speed.
It has the disadvantage that it can only be raised to the level of letters. In addition, in an information output device using a semiconductor laser, two light sources are used to irradiate a 400 mm long photosensitive drum using a Coriolis mirror, so the overall size of the device must be increased to ensure the optical path length. This made it unsuitable for miniaturization.

An information output device using a guest-host liquid crystal cell is compact, but the response speed of the liquid crystal is slow at several tens of m5ec, and a new method using a ferroelectric liquid crystal cell has been proposed.

However, in a liquid crystal device using such a ferroelectric liquid crystal, it is naturally required that the drive characteristics be uniform throughout the device. To this end, technology has been developed with the aim of forming a defect-free and uniform liquid crystal phase, ie, a monodomain, over the entire liquid crystal device.

However, liquid crystal materials, especially ferroelectric liquid crystals with a smectic layer structure, are subject to various problems such as minute scratches on the alignment film, irregularities in the electrodes for driving the liquid crystal, spacers used to maintain a constant distance between the substrates of the liquid crystal device, etc. Depending on the cause, defects occur in the layer structure and uniform monodomains cannot be obtained.For this reason, conventionally, monodomains were grown over the entire cell by one-dimensional crystal growth (temperature gradient) from the edge of the liquid crystal device. There was an attempt to make him do it.

However, this method was not applicable when the length of the liquid crystal device became long. That is, the size of the monodomain realized by this method is at most several tens of millimeters square, and it has been impossible to make it long and use it industrially.

Furthermore, even if a usable monodomain were to be realized, the property of the ferroelectric liquid crystal material is that the liquid crystal material will not be aligned parallel to the substrate, but will be aligned with a certain inclination. The layered structure can bend or break. For this reason, there is a problem in that zigzag defects occur during the main display, resulting in non-uniformity in display performance and drive characteristics.

The liquid crystal material is exposed to an external electric field.

When changing the possible states, there is a phenomenon in which the zigzag defect becomes the boundary and the process becomes reversed. For this purpose, in the entire device.

There was also the problem of not being able to obtain uniform drive characteristics.
Adjust the electrode part of the liquid crystal cell to match the resolution of the optical shutter,
It was necessary to form a fine pattern, but when using the conventional photolithography method, it is not possible to narrow the distance between adjacent electrodes, and the overall dimensions of the device are determined, so as a result, However, it has been pointed out that the electrode area becomes smaller and the density of the portion of the shutter that occupies a unit area becomes smaller, which is a drawback, and an alternative means has been desired.

[Means to solve the problem]

A first substrate having a 1000mm thick SiO7 film on a 1.1mm thick soda lime glass (for example)
1) A first substrate consisting of one electrode and lead made of a light-transmitting conductive material on the top, and a plurality of electrodes and leads made of a light-transmitting conductive material on the light-transmitting substrate. A ferroelectric liquid crystal composition containing a liquid crystal exhibiting ferroelectricity and having an ester bond in its main skeleton is filled inside a liquid crystal cell in which a second substrate is provided in a parallel position. This information output device is characterized in that a liquid crystal electro-optical device having means for arranging the images in a certain direction is provided between a photosensitive drum and a light source. When processing the shapes of the electrodes on the first and second substrates of this liquid crystal cell, IT◯ is directly processed at least once using an excimer laser. This made it possible to achieve fine electrode spacing that was not possible with conventional photolithography.

In addition, by including a liquid crystal composition containing an ester bond in the main skeleton in the liquid crystal composition, a multi-domain state is created, and alignment defects in the liquid crystal are alleviated by the boundaries of the domains, so that the entire liquid crystal cell , zigzag defects, etc. do not occur.

Furthermore, since the inside of this microdomain is in a good monodomain state, there is no difference in the display or drive of the liquid crystal in each microdomain, and the device as a whole can achieve uniform display or drive characteristics. It is something that can be done.

Examples are shown below.

〔Example〕

FIG. 1 shows a schematic cross-sectional view of a cell of a liquid crystal device used in this example. Further, FIG. 2 shows a configuration diagram of the information output device. Since both figures are schematic diagrams, their dimensions are arbitrary.

In this example, soda lime glass (9) was used as the first substrate.
5i film formed by sputtering on the glass substrate (1.1 mm thick) to block the precipitation of alkali ions in the glass substrate.
Six samples containing 1000 02 membranes were used. A translucent conductive film (2) (IT○; indium tin oxide) was formed on the first substrate (1) by sputtering at 1100%
I set up a person. Thereafter, using an excimer laser processing system having the configuration shown in FIG. 3, individual electrodes, external electrodes, and leads were formed.

In this example, as the second substrate (6), a 6 substrate having 1000 5in2 films on sortalime glass (1.1 mm thick) was used. 1,100 light-transmitting conductive films (5) were provided on the second substrate (6). Then, using the same excimer laser processing method, 4800 printed electrodes,
External lead electrodes and leads were formed. The pitch of these printed electrodes was 62.5 mm and 7 oV. Further, the separation width between the electrodes was set to 10 microns.

The laser optical system shown in Fig. 3 used here includes an excimer laser oscillator (30), a computer (31), a laser optical system (32), and a TV camera/monitor system (35).
34), is composed of an x-y-theta table controller (36), and the optical system (32) processes the light from the laser body into a long flat shape and processes it into a linear pattern. .

In addition, 5,000 nickel plating (7) and 500 gold plating (8) were applied to the leads and extraction electrodes.

A polyimide film was printed on the first substrate by an offset method, and baked in a far infrared oven at 350°C for 10 minutes.
An alignment film (3) for 0 people was obtained. Thereafter, rubbing was performed using a rubbing device in which a Chargenon cloth (manufactured by Fuikasei Co., Ltd.) was wound around a roll to make fine scratches in a certain direction on the alignment film (3).

A mixture of 5% by weight of cylindrical SiO□ fibers having a diameter of 2.2 μoV in a one-component epoxy resin was printed (4) on the first substrate using a screen method.

After that, after bonding the first substrate and the second substrate together, a liquid crystal exhibiting diferroelectricity (5ELT-5) was added using a vacuum injection method.
00) αω was injected. A liquid crystal cell was created by sealing the injection port with an ultraviolet curing resin.

After that, a gold bump of 100 microns square and 20 microns in height was installed on the output terminal of the driver IC (9), which is a multiplexer that shifts 8-bit data from the controller, and an external electrode (8) on the second substrate. A liquid crystal device was fabricated by electrically contacting the IC surface and the second substrate, and connecting and fixing the IC surface and the second substrate with epoxy resin 01).

This liquid crystal device was installed between a light source in which LEDs were arranged on a line and a photosensitive drum to constitute an information output device.

The liquid crystal cell of the present invention has an LED light source (21) as (22).
) and the photoreceptor drum (23), and two deflection plates (not shown) are provided to function as a shutter that transmits or blocks light depending on an input signal.

In the case of this example, 4800 lights are turned on for one line.

I was able to perform good ○N and ○FF control of the light for those 4800 lights, although I had to turn them off. This may be due to the orientation of the liquid crystal in the liquid crystal cell or the multi-domain state, and the light could be uniformly turned on and off at the end of the screen.

In addition, since there are small alignment defects on the entire surface of the liquid crystal cell, there are no large alignment defects, and the light can be turned on or off.
There were no parts that looked different from other parts.

In addition, since a ferroelectric liquid crystal material is used as the liquid crystal material, the response speed is 2 to 10 times more than that of conventional liquid crystals, and the output speed of standard A4 size documents is more than twice that of conventional devices. I was able to do it.

Since excimer laser processing was used to form electrodes on the substrate of the liquid crystal cell, the electrode spacing could be made very narrow, and the liquid crystal cell could be formed using a completely dry process.

〔effect〕

According to the present invention, by performing multi-domain alignment on a liquid crystal cell in an information output device, it was possible to obtain a uniform alignment state over the entire liquid crystal cell.

Uniform display characteristics and a high contrast ratio were achieved without the occurrence of defects such as zigzag defects that have a large optical effect.

Particularly in liquid crystal devices used in information output devices, high contrast is required, and the present invention has made it possible to improve the characteristics.

In addition, since direct shaping of ITO using an excimer laser was used for the electrode parts, the separation width between the electrodes could be reduced from 25 microns to 10 microns compared to conventional photolithography.
This makes it possible to increase the pixel area ratio by 1.87 times.

Additionally, by mounting the driver IC on the second board, it has become possible to reduce the weight by 70% and the external size by 60% compared to conventional equipment that uses FPC and packaged ICs.

[Brief explanation of drawings]

FIG. 1 shows a cross-sectional view of the liquid crystal device used in the present invention. FIG. 2 shows a sectional view of the information output device used in the present invention. FIG. 3 shows a schematic diagram of the excimer laser processing apparatus used in the present invention.

Claims (1)

[Scope of Claims] 1. A liquid crystal cell comprising a pair of transparent substrates and a liquid crystal composition material exhibiting ferroelectricity filled between the pair of substrates, the pair constituting the liquid crystal cell. A method for producing an optical shutter for an information output device, characterized in that at least one electrode on a transparent substrate is formed into a predetermined pattern by excimer laser processing. 2. A method for producing an optical shutter for an information output device according to claim 1, wherein the liquid crystal composition material includes a liquid crystal composition having an ester bond in its main skeleton.