JPS62153835A - Liquid crystal element - Google Patents

Abstract

PURPOSE:To heat a liquid crystal efficiently and uniformly to adjust temperature accurately and to suppress the increase of the thickness by forming a heating electrode on the inside face of a substrate. CONSTITUTION:A pair of heating electrodes 23 and 23 which are arranged on the outside of common electrodes 22 and 22 and have certain electric resis tance are formed on the inside face of a common electrode substrate 12 in parallel with common electrodes 22 and 22. A metallic film consisting of chro mium or the like is stuck to transparent conductive materials consisting of indium oxide or the like to constitute heating electrodes 23 and 23 similarly to common electrodes 22 and 22. When power is supplied to heating electrodes 23 and 23, a liquid crystal 15 is heated and is kept at 40+ or -2-5 deg.C proper tempera ture by the balance between this heating and cooling due to a temperature reducing device. Thus, the molecule arrangement of the liquid crystal 15 is changed quickly to secure a good responsiveness.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a liquid crystal element used in an optical writing head of an optical writing printer.

[Technical background of the invention and its problems]

Optical writing printers control light from a light source with a liquid crystal element in an optical writing head, and perform optical writing by irradiating the light beam that passes through the liquid crystal element as a light spot on the surface of a photosensitive drum. The electrostatic latent image on the surface of the photosensitive drum is developed with toner, the developed toner image is transferred to recording paper, and the transferred image is further fixed to form a printed image.

The liquid crystal element used in the optical writing head of such an optical writing printer is required to have quick response, so there is a small operating temperature margin, so it is necessary to adjust the temperature of the liquid crystal layer to keep it at an appropriate temperature at all times. Is required. Therefore, in the past, as shown in FIGS. 5 and 6, a temperature adjustment heater 2 is attached to the outer surface of the signal electrode substrate 1 in the liquid crystal element with an adhesive 3, and the heating by the heater 2 and the temperature decrease (not shown) are performed. The liquid crystal is kept at a constant temperature in balance with the cooling provided by the device. In addition, 4 is a support plate, 5 is a resistance heating element attached to the inner surface of this support plate 4, 6 is a common electrode substrate in the liquid crystal element, and 7 is this common electrode substrate 6
This is a polarizing plate attached to the outer surface of the camera via an adhesive 8.

However, in such conventional means, since the temperature adjustment heater 2 is arranged on the outer surface of the signal electrode substrate 1,
Heat conduction to the liquid crystal interposed between the signal electrode substrate 1 and the common electrode substrate 6 is poor, making it difficult to efficiently and uniformly heat the liquid crystal and adjust the temperature accurately, and the temperature adjustment heater 2 increases the thickness of the liquid crystal element, and furthermore, the temperature adjustment heater 2 must be constructed separately from the liquid crystal element and attached to the outer surface of the signal electrode substrate 1 each time, which reduces manufacturing efficiency. However, there was a problem in that the performance decreased and the cost increased.

[Purpose of the invention]

This invention was made with attention to these points, and its purpose is to efficiently and uniformly heat the liquid crystal to achieve accurate temperature control, while also suppressing the increase in thickness. It is an object of the present invention to provide a liquid crystal element that can be constructed thinly and can be manufactured efficiently and at low cost.

[Summary of the invention]

In other words, this invention provides a transparent pair of 2! A first electrode is formed on the inner surface of one of the substrates, a second electrode is formed on the inner surface of the other substrate, and a gap between the opposing first and second electrodes is formed. In this device, a heating electrode is formed on the inner surface of the other substrate.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

In the figure, reference numerals 11 and 12 denote a pair of substrates each made of a transparent glass plate. They are bonded to each other via a pair of inner sealing materials 13b, 13b. Both ends of the inner sealing materials 13b, 13b are integrally connected to both sides of the outer sealing material 13a,
The area between the substrates 11 and 12 and surrounded by the outer sealing material 13a and the inner sealing materials 13b and 13b becomes an air sealed space 14.14. Inner seal material 13b
, 13b communicates with the wide parts at both ends of the outer sealing material 13a, and the liquid crystal 15 is filled in the narrow part and the wide part between the substrates 11 and 12. This liquid crystal 15
is injected from a liquid crystal injection hole 16 provided in the outer sealing material 13a, and after injection, the liquid crystal injection hole 16 is sealed with a sealing material 17.

On the inner surface of one of the substrates 11 (hereinafter referred to as the signal electrode substrate), in the narrow part between the inner sealing materials 13b, 13b,
A large number of signal electrodes 18 are formed in parallel over the entire length, and leads 19 are alternately connected to one side and the other side of the signal electrode substrate 11 from these signal electrodes 18.
... are derived in parallel, and further these leads 19...
A terminal 20 is formed at the tip of the terminal. These signal electrodes 18..., leads 19..., terminals 20... are integrally formed on the inner surface of the signal electrode substrate 11 from a transparent conductive material such as indium oxide, and among these electrodes, A metal film 24 made of chromium or the like is bonded to a portion of the signal electrode 18 other than a portion corresponding to the shutter portion S and on the lead 19.

On the inner surface of the other substrate 12 (hereinafter referred to as the common electrode substrate), a pair of band-shaped common electrodes 22, 22 are provided opposite to each signal electrode 18 of the signal electrode substrate 11.
The common electrodes 22 and 22 are formed of a transparent conductive material such as indium oxide at minute intervals in parallel with each other along the longitudinal direction of the common electrodes 22 and 22, and a metal film 25 of chromium or the like is adhered on top of these common electrodes 22 and 22, except for the portion corresponding to the shutter portion C. has been done. A shutter section S for controlling transmission of light is formed by the opposing portion of the signal electrodes 18 and the common electrodes 22 and 22. Further, on the inner surface of the common electrode substrate 12, a pair of heating electrodes 23.23 are formed in parallel with the common electrode 22.22, and are arranged outside the common electrode 22.22 and have a certain electric resistance. These heating electrodes 23.23, for example, like the common electrode 22.22, are constructed by adhering a metal film such as chromium onto a transparent conductive material such as indium oxide.

Note that the metal film 24 is connected to the signal electrode 18 and the lead 19.
The metal film 25 is provided to reduce the electrical resistance of the common electrode 22 and to regulate the light transmission area of the shutter section S. 25a shown in FIG. 3 is the metal film 2
This is the vacant light transmitting portion No. 5 (the portion where the common electrode 22 is exposed). Furthermore, 26.26 shown in FIG. 1 is a sealing material 13b.
.

A liquid crystal alignment film is provided on the inner surfaces of the signal electrode substrate 11 and the common electrode substrate 12 within the narrow width portion 13b.

However, in such a liquid crystal element, the heating electrode 23
．． At the same time, the signal electrodes 18... and the common electrodes 22.degree. 22 are energized through the drive circuit, and a driving voltage is applied between the signal electrodes 18.. and the common electrodes 22.degree. Then, the molecular arrangement structure of the liquid crystal in the area where the drive voltage is applied changes, and this change opens or closes the shutter section S, thereby controlling the transmission of light through the shutter section S.

In addition, when electricity is applied to the heating electrodes 23.23, these heating electrodes 23.23 generate heat, and this heat generation heats the liquid crystal 15. In balance with cooling by a temperature lowering device (not shown), for example, 4o ± 2 to 5 The temperature is maintained at an appropriate temperature of .degree. C., so that the molecular arrangement of the liquid crystal 15 changes quickly and good responsiveness can be ensured. In addition, unlike the conventional method in which a heater for adjusting H degree is attached separately on the outer surface of the liquid crystal element, the heating electrodes 23.23 are arranged on the inner surface of the common electrode substrate 12 near the area where the liquid crystal 15 is arranged. The liquid crystal 15 can be heated efficiently and accurately and uniformly, and its temperature can be adjusted accurately, and the overall thickness of the liquid crystal element can be reduced. However, the heating electrodes 23.23 can be patterned at the same time as the process of forming the common electrodes 22.22 on the inner surface of the common electrode substrate 12, which greatly reduces production efficiency and cost. It will be advantageous.

As for the constituent material of the heating electrodes 23 and 23, it is most preferable to have the same structure as the electrodes as in the above embodiment in terms of production efficiency and cost, but it is also possible to use other resistors. be. In this case, examples include metal film materials having electrical resistance, such as metal oxide films and carbon. Further, when the heating electrode is made of a transparent conductive material such as indium oxide, a metal film, etc., methods of forming the electrode include vapor deposition, sputtering, printing, electrolytic plating, and electroless plating.

FIG. 4 shows another embodiment of the invention, in which the common electrode 22.
22 and the terminals of the heating electrode 23 are arranged close to one side of the common electrode substrate 12.

It goes without saying that the liquid crystal element according to the present invention can be used not only by being incorporated into the optical writing head of an optical writing printer, but also by being incorporated into various other devices and used for other purposes. stomach.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to efficiently and uniformly heat the liquid crystal to achieve accurate temperature adjustment, and it is also possible to suppress the increase in thickness, make it thinner, and achieve efficient and inexpensive manufacturing. This has the effect of being able to achieve the following.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the invention, FIG. 2 is a plan sectional view, FIG. 3 is a plan view showing an inverted common electrode substrate, and FIG. 4 is another embodiment of the invention. FIG. 5 is a plan view showing the common substrate in the example inverted, FIG. 5 is a perspective view showing the prior art, and FIG. 6 is a sectional view. 11.12...Substrate, 15...Liquid crystal, 18...Signal electrode, 22...Common electrode, 23...Heating electrode, S
...Shutter section.

Claims (2)

[Claims] (1) A pair of transparent substrates are placed facing each other with a liquid crystal in between, a first electrode is formed on the inner surface of one of the substrates, a second electrode is formed on the inner surface of the other substrate, and these first and second electrodes are formed on the inner surface of the other substrate. 1. A liquid crystal device comprising a shutter section for controlling transmission of light between opposing second electrodes, characterized in that a heat generating electrode is formed on the inner surface of the other substrate. (2) The liquid crystal device according to claim 1, wherein the heating electrode is made of the same material as the common electrode.