JPH05173165A - Manufacture of liquid crystal display device - Google Patents

Abstract

PURPOSE:To make the display density uniform and improve the display quality by decreasing the conductivity of a 1st electrode pattern including a display electrode toward the input terminal of a 2nd electrode pattern by utilizing laser light. CONSTITUTION:Terminal electrodes 6a-6d are exposed at the extension part 13 of a 1st substrate which extends toward a 2nd substrate 2 and terminal electrodes 9a-9d are exposed at the extension part 14 of the 2nd substrate 2 which extends to the 1st substrate 1. When the terminal electrodes 6a-6a are irradiated with, for example, YAG laser light in the order while the spot diameter 15 is decreased stepwise, the terminal electrodes 6a-6d which are irradiated change in composition of ITO films constituting the electrodes and increase in resistance. The composition change is smaller and smaller and the variation in resistance value is smaller and smaller as the irradiation area is made smaller and smaller. Therefore, respective display electrodes 5a-5d can be applied with uniform driving signal voltages.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid crystal display device in which liquid crystal is filled between two substrates having display electrodes on opposite surfaces.

[0002]

2. Description of the Related Art Liquid crystal display devices are used in a wide range of applications because of their features of low power consumption, small size and light weight.
Recently, in addition to the conventionally used TN (twisted nematic) type, the twist angle of liquid crystal molecules is 180 °.
With the development of the birefringence mode liquid crystal display device as described above,
Large-capacity, high-visibility displays for personal computers and word processors are becoming possible, and their applications are expanding. Generally, a liquid crystal display device has a structure in which a liquid crystal is sandwiched between two glass substrates having transparent display electrodes formed in a strip shape on the surface.

Such a liquid crystal display device has a structure in which a plurality of strip-shaped display electrodes which are orthogonal to each other are formed on two glass substrates. Then, the tip of the display electrode for inputting a drive signal to the display electrode is exposed to the end of the glass substrate via the wiring electrode to form a terminal electrode. A common driver and a segment driver for inputting a drive signal to this are connected to the respective glass substrates for display.

[0004]

By the way, when a display operation is performed in this type of liquid crystal display device, the display dots far from the common driver and the segment driver are driven by the resistance value of the electrodes as compared with the display dots in the vicinity. Since a signal voltage drop occurs, the display density becomes low, and there is a problem that uniform display cannot be performed in the entire display device. In order to eliminate such a display density difference, a method has been proposed in which the width of the wiring electrode pattern is corrected in advance when the electrode pattern is formed and the resistance value of the display electrode is changed. However, when the resistance value is changed depending on the width of the wiring electrode pattern, the pattern width may become too narrow, which may cause a problem such as disconnection. It was difficult to make the display density uniform by making the voltage uniform. The present invention has been made in view of such conventional circumstances.

[0005]

SUMMARY OF THE INVENTION The present invention is a liquid crystal display device in which liquid crystal is sandwiched in a gap between first and second substrates having first and second electrode patterns formed on opposite surfaces thereof. Of the manufacturing method of the first electrode pattern, and includes a step of irradiating the first electrode pattern with a laser beam to reduce the conductivity of the first electrode pattern as it approaches the input terminal of the second electrode pattern.

[0006]

According to the present invention, the first electrode pattern is treated with laser light so that the conductivity of the first electrode pattern decreases as it approaches the input terminal of the second electrode pattern to which the drive signal is applied. Thereby, the display voltage can be made uniform by keeping the supply voltage to each display electrode in the first electrode pattern constant.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the present invention,
FIG. 2 is a sectional view corresponding to the AA ′ axis in FIG. Figure 1
2 will be described in accordance with the manufacturing process, the first electrode pattern 3 and the second electrode pattern made of, for example, an ITO film are formed on one main surface of the first substrate 1 and the second substrate 2 made of glass, respectively. 4 is formed. Here, the first electrode pattern 3 is composed of a plurality of display electrodes 5a, 5b, ... 5d, terminal electrodes 6a, 6b, ... 6d and wiring electrodes 7a, 7b ,. It has segment electrodes. Further, the second electrode pattern 4 also has the display electrode 8 similarly to the first electrode pattern 3.
8d, terminal electrodes 9a, 9b, ... 9d and wiring electrodes 10a, 10b, ... 10 connecting these electrodes.
It has a plurality of common electrodes each constituted by d. Next, the first and second substrates 1 and 2 are combined with each other, for example, with a sealant 11 so that their main surface sides face each other, and a liquid crystal 12 is held in this gap. Here, the terminal electrodes 6a, 6b, ... 6d are provided on the extension 13 of the first substrate 1 with respect to the second substrate 2, and the terminal electrodes are provided on the extension 14 of the second substrate 2 with respect to the first substrate 1. 9a, 9b, ... 9d are exposed. Then, the terminal electrodes 6a, 6b, ..., 6d are irradiated in this order so as to reduce the spot diameter 15 of the YAG laser light stepwise, for example.
In 6a, 6b, ... 6d, the composition of the ITO film forming the electrodes changes, and the resistance value increases. At this time, the smaller the irradiation area, the smaller the change in composition and the smaller the change in resistance value.

FIG. 3 is a sectional view showing a state after the terminal electrodes 6a, 6b, ... 6d have been treated with laser light. As can be seen from the figure, the terminal electrodes 6a, 6b, ... Close to the terminal electrodes 9a, 9b ,.
The irradiation area 20 of the laser light is increased by about 6d. As a result, in this embodiment, the closer the display electrodes 5a, 5b, ... Can be given.

In this embodiment, the irradiation portion of the laser beam is not limited to the terminal electrodes 6a, 6b, ... 6d, but may be the wiring electrodes 7a, 7b ,. Further, although the case where the first electrode pattern 3 is the segment electrode and the second electrode pattern 4 is the common electrode has been described so far, conversely, the first electrode pattern 3 is the common electrode and the second electrode pattern 3 is the common electrode.
It goes without saying that the present invention can be applied to the case where the electrode pattern 4 of 4 is a segment electrode.

[0011]

According to the present invention, the conductivity of the first electrode pattern including the display electrode is reduced by utilizing the laser beam as the input terminal of the second electrode pattern is approached. A uniform drive signal voltage can be applied, the display density becomes uniform, and the display quality is improved.
Further, it is not necessary to correct the electrode pattern width when designing the electrode pattern, and stable electrode design can be performed even in a high-definition display device.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view corresponding to the AA ′ axis in FIG.

FIG. 3 is a cross-sectional view showing a state after processing with laser light in the example shown in FIG.

[Explanation of symbols]

 1 ... First substrate 2 ... Second substrate 3 ... First electrode pattern 4 ... Second electrode pattern 12 ... Liquid crystal

Claims (1)

[Claims] 1. A method of manufacturing a liquid crystal display device, wherein liquid crystal is sandwiched between gaps of first and second substrates having first and second electrode patterns formed on mutually opposing surfaces, respectively.
A liquid crystal display device comprising: a step of irradiating the first electrode pattern with laser light to reduce the conductivity of the first electrode pattern as the input electrode of the second electrode pattern is approached. Production method.