JPH0643436A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide a liq. crystal display device ensuring prescribed display characteristics independently of ambient temp. CONSTITUTION:A transparent conductor pattern 3 for temp. regulation as well as a segmented electrode 2 for display is formed on the surface of a glass sheet 1, electric current is supplied from an AC signal source 12 to the pattern 3 and the resulting liq. crystal display device is kept at a constant temp. with Joule heat generated by supplying the electric current.

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, and more particularly to a liquid crystal display which is not easily affected by ambient temperature.

[0002]

2. Description of the Related Art A generally well-known liquid crystal display device stores a liquid crystal in an empty chamber composed of two glass plates and a sealing material for separating the two glass plates by a predetermined distance. A common electrode is formed on one of the two glass plates in the room, a segment electrode is formed on the inner surface of the other glass plate, and a voltage is applied between the segment electrode and the common electrode selected according to the display content. Thus, the characteristic of the liquid crystal in the selected segment portion is changed to change the color with the other portion, and the display operation is performed. Further, the electrodes may be arranged in a grid pattern with respect to each other.

[0003]

The liquid crystal display is often used by itself or with the incorporated electronic equipment body by being moved or carried. For this reason, the operating temperature varies depending on the location, and when it is used particularly in a severe cold, the display responsiveness is deteriorated and dew condensation occurs, which is easily affected by the temperature. In particular, since liquid crystals have intermediate characteristics between liquid and solid, the display characteristics change drastically with temperature,
Moreover, there is a problem that the operating temperature range is strongly limited.

The present invention has been made in view of the above problems, and an object thereof is to provide a liquid crystal display device which can obtain a predetermined display characteristic without being affected by ambient temperature.

[0005]

The liquid crystal display of the present invention is a liquid crystal display in which liquid crystal is housed in a vacant chamber formed by two glass plates and a sealing material. A transparent conductor pattern that generates heat when energized is formed. In this liquid crystal display, for example, even if the ambient temperature is low, the Joule heat generated by energizing the transparent conductor pattern can raise the temperature of the liquid crystal to an appropriate temperature, so that a constant display characteristic is always obtained. be able to.

[0006]

The present invention will be described in more detail with reference to the following examples. FIG. 1 is a plan view showing an arrangement example of a transparent conductor pattern on a glass plate on one side of a liquid crystal display showing an embodiment of the present invention. FIG. 2 is a cross-sectional view of the liquid crystal display device of the same embodiment. In this embodiment liquid crystal display 10, a transparent segment electrode 2 for display and a transparent conductor pattern 3 for temperature adjustment are formed on the inner surface of the upper glass plate 1. Here, the segment electrode 2 for display and the conductor pattern 3 for temperature adjustment are arranged so as not to overlap and not intersect. In FIG. 1, reference numeral 4 is a sealing material.

In the liquid crystal display of this embodiment, as shown in FIG. 2, the liquid crystal 5 is housed in an empty space formed by two glass plates 1 and 5 and a sealing material 4. Further, a segment electrode 2 and a transparent conductor pattern 3 coated with polyimide 7 are formed on the back surface of the glass plate 1, and a common electrode 6 coated with polyimide 8 is provided on the upper surface, that is, the inner surface of the glass plate 5. There is. Further, polarizing plates 9 and 11 are arranged outside the glass plates 1 and 5, respectively. However, the liquid crystal display having the above-mentioned configuration except the transparent conductor pattern 3 is well known.

The liquid crystal display device 10 of this embodiment is characterized in that a transparent conductor pattern 3 is provided together with the display segment 2. An AC signal source 1 is attached to the transparent conductor pattern 3.
As shown in FIG. 2, when electricity is applied, Joule heat is generated, and this heat can keep the temperature of the liquid crystal display 10 constant. In particular, even when the liquid crystal display is used in a low temperature environment, the liquid crystal display can be maintained at a predetermined temperature, so that the use effect is great, the response speed at a low temperature is prevented from decreasing, and the operating temperature range can be expanded. Further, if the temperature of the liquid crystal display is kept constant at the MAX value of the operating temperature in use, the characteristics can be kept constant within the entire operating environment temperature range.

FIG. 3 is a plan view showing another embodiment of the present invention. In this embodiment, the common electrode 6 is also used as the transparent conductor pattern 3 for energizing for temperature adjustment. In this liquid crystal display, the applied voltage for energization is applied so as to overlap the common voltage waveform. However, the applied voltage is set to a frequency that does not affect the liquid crystal display function. FIG. 4 is a plan view showing still another embodiment of the present invention. In this liquid crystal display, a temperature sensor 13 is provided near the transparent conductor pattern 3 for energizing for temperature adjustment. The temperature sensor 13 detects the temperature of the liquid crystal display and automatically adjusts the temperature to the target temperature.
By controlling the current flowing through the transparent conductor pattern 3 with the controller, the temperature of the liquid crystal display, and thus the display characteristics, can be maintained more accurately.

In the above embodiments, the case where the transparent conductor pattern for energization is provided on the inner surface of the glass plates 1 and 5, that is, inside the liquid crystal gap, has been described. You may form in. In this case, the power supply for energization may be alternating current or direct current.
Further, in the above embodiment, the case where the display portion is a Japanese character type segment is given as an example, but it goes without saying that the present invention can be applied to other display types such as a dot type.

[0011]

According to the present invention, on one surface of the glass plate,
Since the transparent conductor pattern that generates heat when energized is formed, even if the ambient temperature becomes extremely low, the generated heat keeps the liquid crystal display at a constant temperature by energizing this transparent conductor pattern. Therefore, constant display characteristics can be obtained without being affected by the ambient temperature.

[Brief description of drawings]

FIG. 1 is a plan view showing a display segment pattern of a liquid crystal display according to an embodiment of the present invention and a transparent conductor pattern for conducting electricity.

FIG. 2 is a cross-sectional view of an example liquid crystal display.

FIG. 3 is a plan view showing a common electrode and a conductive transparent conductor pattern of a liquid crystal display according to another embodiment of the present invention.

FIG. 4 is a plan view showing the arrangement of a transparent conductor pattern for energization and a temperature sensor of a liquid crystal display according to still another embodiment of the present invention.

[Explanation of symbols]

 1 glass plate 2 display segment electrode 3 transparent conductor pattern 12 for temperature adjustment AC signal source

Claims (1)

[Claims] 1. A liquid crystal display in which liquid crystal is housed in a vacant chamber formed by two glass plates and a sealing material, and a transparent conductor pattern for generating heat when energized is formed on one surface of the glass plate. A liquid crystal display characterized in that