JPH04269711A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To detect the liquid crystal charged in the liquid crystal display element as accurately and fast as possible while the liquid crystal display element is driven. CONSTITUTION:Glass substrates 2 and 7 which have at least transparent electrodes 4 and 10 and orienting films 6 and 12 provided on one-surface sides are arranged with the orienting films 6 and 12 opposite each other and the liquid crystal is charged in the gap between the orienting films 6 and 12 to constitute the liquid crystal element. A recessed part 15 is formed in one glass substrate on the surface on the side where the transparent electrode is provided and a temperature detector 16 is provided in the recessed part 15.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display element.

0002

[Prior Art] Liquid crystal display elements conventionally used in watches, televisions, computer displays, etc. basically have the following characteristics:
It has a structure in which two glass substrates each having at least a transparent electrode and an alignment film provided on one side are arranged so that the alignment films face each other, and liquid crystal is sealed in the gap between the alignment films. Various types of liquid crystals have been used as this liquid crystal, but recently ferroelectric liquid crystals having high-speed response have been mainly used.

As the requirements for liquid crystal display elements become more diverse and sophisticated, various liquid crystal compositions have been developed. Some of these liquid crystal compositions have a suitable driving temperature range that is higher than the environmental temperature, and in order to use the liquid crystal to its full potential, it is necessary to adjust the liquid crystal in the liquid crystal display element. , it is desirable to maintain it at all times within its operating optimum temperature range. For example, if the temperature of the liquid crystal in the liquid crystal display element is higher than the suitable driving temperature range, crosstalk will occur in the display, and if it is lower than the suitable driving temperature range, the response will be slow.

Until now, no particular consideration has been given to maintaining the liquid crystal display element within the optimum temperature range for driving the liquid crystal, or even when maintaining the liquid crystal display element within the desired temperature range, temperature detection has been carried out on the outer surface of the liquid crystal display element. A device was attached to detect and control the temperature of the liquid crystal display element. However, in order to maximize the performance of a liquid crystal display element, it is desirable to control the temperature of the liquid crystal in the liquid crystal display element so as to maintain it as strictly as possible within its suitable driving temperature range. First, it is necessary to detect the temperature of the liquid crystal in the liquid crystal display element as quickly and accurately as possible.

[0005] Conventionally, when a temperature sensor is attached to the outer surface of a liquid crystal display element, it is affected by the environmental temperature, and there is a delay in detecting the liquid crystal temperature because it is measured through a glass substrate. Therefore, it was not possible to accurately detect the temperature of the liquid crystal, and there was no guarantee that the temperature of the liquid crystal in the liquid crystal display element was maintained within the optimum temperature range.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal display element that can detect the temperature of liquid crystal sealed in the liquid crystal display element as accurately and quickly as possible while the liquid crystal display element is being driven.

[0007]

[Means for Solving the Problems] The present invention provides two glass substrates each having at least a transparent electrode and an alignment film on one side, arranged so that the alignment films face each other, and a gap between the alignment films. A liquid crystal display element in which a liquid crystal is sealed in a glass substrate, a recess is formed on the surface of one of the glass substrates on the side where the transparent electrode is provided, and a temperature sensor is provided in the recess. This is a liquid crystal display element characterized by the following.

Preferred embodiments of the present invention are as follows. (1) The above-mentioned temperature sensor is a thermistor, a critesistor,
The above-mentioned liquid crystal display element is characterized in that it is a thermocouple, a platinum resistor, a nickel resistor, or a copper resistor.

(2) The liquid crystal display element is a liquid crystal matrix type display element, and the substrate in which the recessed portion is formed is further provided with a black mask and/or a color filter, and the recessed portion is provided with a black mask and/or a color filter. The above-mentioned liquid crystal display element is provided at a position corresponding to a non-light-transmitting part.

(3) The above-mentioned liquid crystal display element is characterized in that the above-mentioned liquid crystal display element is a liquid crystal segment type display element, and the above-mentioned recess is provided at a location corresponding to a portion where no segment is provided. .

The present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is an enlarged and schematic cross-sectional view of a part of an embodiment of a liquid crystal display element of the present invention. In FIG. 1, a liquid crystal display element 1 includes a smooth layer 3 on a glass substrate 2,
A transparent electrode 4, an insulating film 5, and an alignment film 6 are provided in this order, while a black mask 8, a smooth layer 9, a transparent electrode 10, an insulating film 11, and an alignment film 12 are provided in this order on a glass substrate 7. The gap between the alignment film 6 and the alignment film 12 is filled with liquid crystal 13.

Each of the transparent electrodes 4 and the transparent electrodes 10 is composed of a plurality of pieces, and the transparent electrodes 4 and the transparent electrodes 10 are orthogonal to form a plurality of display pixels in a matrix type. The black mask 8 is provided with a window 8a for transmitting light. A recess 15 is provided on the surface of the substrate 7 corresponding to the frame 8b, which is a part of the black mask 8 that does not transmit light. A temperature sensor 16 is fixed in the recess 15, and a lead wire of the temperature sensor 16 is provided. (not shown) is taken out to the outside of the liquid crystal display element 1.

The temperature detector 16 may be a temperature detector whose electrical resistance value or electromotive force changes depending on temperature, such as a thermistor, critegister, thermocouple, platinum resistor, nickel resistor, or copper resistor. It is preferable that For example, the temperature is detected by passing a current through the temperature detector 16 whose electrical resistance value changes and measuring the current value. A minute current is passed through the temperature detector 16, amplified and compared with a verification line, converted into a temperature value, and can be displayed digitally. In addition, the current value passing through the temperature detector 16 is compared with the current value corresponding to a predetermined temperature obtained from the verification line, and a heater provided outside the liquid crystal display element is turned on to compensate for the difference. -Perform the OFF operation. That is,
When the temperature obtained from the temperature detector 16 is lower than a predetermined temperature, heating is performed by the heater, and when the temperature obtained from the temperature detector 16 is higher than the predetermined temperature, heating by the heater is stopped, Leave to cool. In this way, the temperature of the liquid crystal display element can be maintained within a predetermined temperature range. These operations can be performed automatically using a computer. Even in the case of a temperature detector whose electromotive force changes with temperature changes, the temperature of the liquid crystal display element can be maintained within a predetermined temperature range in the same manner as described above. As a temperature control means, means such as proportional control, PID control, and fuzzy control can be used.

Alternatively, instead of providing the heater, the temperature value obtained from the temperature detector 16 is compared with a temperature in a predetermined range, and the output of the liquid crystal driver for driving the liquid crystal display element is determined based on the temperature difference between the two. Through control, the temperature of the liquid crystal can also be maintained within a predetermined range.

Recess 15 for accommodating temperature sensor 16
may be provided anywhere on the surface of the substrate 7 on which the transparent electrode 10 is provided. However, it is preferable to provide it at a location where it does not interfere with the display function of the liquid crystal display element 1. For example, in a liquid crystal display element provided with a black mask, as shown in FIG. 1, a recess 15 is provided at a location on the surface of the substrate 7 corresponding to the frame 8b, which is a portion of the black mask 8 that does not transmit light. It is preferable. In a liquid crystal display element in which a color filter is provided instead of a black mask or together with a black mask, the surface of the substrate corresponding to the non-light-transmitting portion of the black mask and/or color filter is similar to the embodiment shown in FIG. It is preferable to provide a recess at the location.

When the liquid crystal display element is a liquid crystal segment type display element, it is preferable to provide segments on the surface of the substrate corresponding to portions where no segments are provided.

[0017] In the present invention, any number of temperature detectors, including one or two or more, may be provided.

The liquid crystal display element of the present invention is a liquid crystal matrix type display element in which a plurality of transparent electrodes 4 and a plurality of transparent electrodes 11 are formed, and the transparent electrodes 4 and transparent electrodes 11 are orthogonal to each other to form a display pixel. There may be. The liquid crystal display element of the present invention may be either black and white or color, and by providing RGB color filters as filters in adjacent display dots, it can be used as a full-color matrix type display element such as a liquid crystal color television panel. It can be done.

In the display element of the present invention, the liquid crystal may be of any type, but ferroelectric liquid crystal is particularly preferable, and the liquid crystal is preferably a ferroelectric liquid crystal. Regarding the element drive method etc.
Those known per se can be used.

[0020]

Effects of the Invention In the matrix type display element of the present invention, the temperature sensor is provided in the recess formed in the surface of the substrate on the side where the transparent electrode is provided (the liquid crystal layer side). This display element has a remarkable effect of being able to accurately detect temperature and quickly follow the temperature change of the liquid crystal.

[Brief explanation of the drawing]

FIG. 1 is a schematic, enlarged cross-sectional view of a part of an embodiment of a liquid crystal display element of the present invention.

[Explanation of symbols]

1 Liquid crystal display element 2 Glass substrate 3 Smooth layer 4 Transparent electrode 5 Insulating layer 6 Alignment film 7 Glass substrate 8 Black Mask 9 Smooth layer 10 Transparent electrode, 11 Insulating layer 12 Alignment film 13. LCD, 15 Recess 16 Temperature detector

Claims (1)

[Claims] Claim 1: A liquid crystal produced by disposing two glass substrates each having at least a transparent electrode and an alignment film on one side so that the alignment films face each other, and filling the gap between the alignment films with liquid crystal. A display element, wherein a recess is formed on the surface of at least one of the glass substrates on the side where the transparent electrode is provided,
A liquid crystal display element characterized in that a temperature detector is provided within the recess.