JPH02140721A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To display the picture of high definition without a display defect by forming a number in each picture element electrode with a trimmed pattern in an active matrix display device provided with nonlinear elements. CONSTITUTION:Transparent picture element electrodes 2 consisting of ITO (indium oxide) are arranged in a matrix in respective rectangular areas surrounded with source bus lines 5 and gate lines 4 provided with equal intervals vertically and horizontally in a grating shape on a glass substrate, and an identification number 20 peculiar to each picture element electrode is formed in this electrode with the trimmed pattern of the photolithography method. In this case, since the identification number 20 is formed with the trimed pattern passing through transparent picture element electrodes 2, leak does not occur at the time of driving of liquid crystal because of non-conductive patterns and a display defect does not occur even when patterns are deformed and brought into contact with gate and source bus lines 4 and 5 at the time of formation.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a so-called active matrix liquid crystal display device in which a nonlinear element for switching is added to each of a plurality of picture elements constituting a display screen.

<Prior Art> Conventionally, as this type of active matrix liquid crystal display device, there is one shown in FIG. 3, for example. In this active matrix type liquid crystal display device 31, a display screen is constituted by a plurality of picture element electrodes 32 arranged in a matrix. A thin film transistor 3, which is a nonlinear element for switching, is arranged for each picture element electrode 32, and a gate pass line 4 and a source pass line 5 for driving the thin film transistor 3 are alternately arranged between each picture element electrode 32. It is arranged so that it intersects with the

As shown in FIG. 4, the thin film transistor 3 includes a gate electrode 7 formed on a glass substrate 6 and connected to the gate pass line 4, and a gate insulating film 8.
9 to form a semiconductor '0', and further this semiconductor lθ
Above is the first source electrode connected to the source pass line 5!
I and T52 source electrodes 12 are formed, and a first drain electrode 3 connected to the picture element electrode 32 and a second drain electrode 14 are formed. The active matrix type liquid crystal display device 31 in which a thin film transistor 3 having such a structure is provided for each pixel is manufactured through an extremely complicated manufacturing process. Pixel defects are likely to occur due to deterioration. Therefore, we thoroughly inspect and analyze the defective parts of the product,
It is necessary to ensure thorough quality control. Therefore, it is essential to locate defective pixel electrodes discovered during inspection. Therefore, when forming the gate pass line 4 or the source pass line 5 on the glass substrate 6 in the manufacturing process, each pixel electrode 3
2, the serial number 33 for position identification is made of the same metal material as the pass line.
2" (Utility Application No. 7425, 1983).

<Problem to be solved by the invention> However, the number 33 made of such a metal material is
When pass lines 4 or 5 are formed simultaneously using the photolithography method, if the pattern is distorted or foreign matter is generated, number 33 will come into contact with gate pass line 4 or source pass line 5, causing display defects due to leakage when driving the liquid crystal. There is a risk. Furthermore, since the numbers are formed in the picture element electrodes 32 using opaque metal, there is a drawback that the aperture ratio decreases and the display quality deteriorates.

Therefore, an object of the present invention is to provide high-quality display without the risk of display defects by forming numbers for position identification on each picture element electrode without reducing the aperture ratio. The object of the present invention is to provide a liquid crystal display device that can be used.

<Means for Solving the Problems> In order to achieve the above object, the first liquid crystal display device of the present invention is an active matrix type liquid crystal display device equipped with a nonlinear element, in which each pixel electrode is provided with a punched pattern. It is characterized by the formation of numbers. Further, the second liquid crystal display device of the present invention is an active matrix type device equipped with a nonlinear element, and a number is formed in each picture element electrode in a pattern using a transparent electrode film. Features.

<Function> The first aspect of the present invention. In the second liquid crystal display device, each transparent picture element electrode has a punched pattern that penetrates the picture element electrode, or a pattern left behind by a transparent electrode film under the picture element electrode, instead of the conventional pattern left by a metal material. Since numbers are formed on each panel, the numbers do not come into contact with the pass lines and cause leakage during driving, and the aperture ratio of the picture element electrodes is improved, allowing high-quality display without display defects. In addition, the above-mentioned punching pattern or leaving pattern provides a suitable contrast between the number and the surrounding substrate, and the above-mentioned number, which is unique to the picture element electrode, can be visually confirmed, so the position of the defective part found during product inspection can be determined by this number. clarified and appropriate repairs.

Measures such as repairs can be taken.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 is a plan view showing an example of a first liquid crystal display device of the present invention. This active matrix type liquid crystal display device 1 is made of ITo (indium oxide) in each rectangular area surrounded by source pass lines 5 and gate lines 4, which are provided in a lattice shape at equal intervals in the vertical and horizontal directions on a glass substrate. In addition to arranging transparent picture element electrodes 2 in a matrix,
At the upper left corner of each picture element electrode 2, there is a nonlinear element consisting of a drain electrode connected to this picture element electrode 2, a source electrode S connected to the source pass line 5, a gate electrode G connected to the gate pass line 4, and a semiconductor IO. Thin film transistors 3 are arranged respectively.

Each of the above-mentioned members is the same as the conventional liquid crystal display device described in FIG. 3, except for the picture element electrode 2, and the same members are given the same numbers and the description thereof will be omitted. Further, the structure of the thin film transistor 3 is also exactly the same as that described in FIG.

An identification number 20 unique to the picture element electrode 2 is stamped into the picture element electrode 2 with a pattern of "15.16, 301, 3" in FIG.
It is formed with a serial number such as 02".

The function of the identification number 20 of each picture element electrode 2 in the liquid crystal display device having the above structure is as follows.

The identification number 20 is not formed of a pattern made of the same metal material as the pass line as in the past, but is formed of a punched pattern that penetrates the transparent picture element electrode 2. Therefore, the pattern may be distorted during formation, and this may cause the gate or Even if it comes into contact with the source path line 4.5, since there is no conductivity, no leakage will occur during driving of the liquid crystal, and no display defects will occur. Furthermore, since it is a punched pattern, light is not blocked, and the aperture ratio of the picture element electrode 2 is improved, allowing high-quality display. Furthermore, the cutout pattern provides a suitable contrast between the identification number 20 and the surrounding substrate (2), making it easy to visually confirm the identification number 20, making it easier to locate defects found during product inspection and to Measures such as repairs and remediation can be taken immediately. In other words, the identification numbers 20 formed in the punched pattern on each picture element electrode 2 make it possible to provide a liquid crystal display device with high display quality and no display defects.

FIG. 2 shows an example of a second liquid crystal display device of the present invention. This liquid crystal display device 21 has a first
It has the same configuration as the first liquid crystal display device described in the figures, and the same members are given the same numbers and their explanations will be omitted. In the picture element electrode 22 of this liquid crystal display device, a unique identification number 30 is added to the picture element electrode using ITO or SNO prior to formation of the picture element electrode.
Using a transparent electrode material such as w, the remaining pattern is made by photolithography, and the "l 5, 16, 301,
It is formed with serial numbers such as 302''.

The function of the identification number 30 of each picture element electrode 22 is essentially no different from that in FIG. 1. That is, since the identification number 30 is formed not by a pattern made of a metal material as in the past, but by a pattern left by a transparent electrode under the picture element electrode 22, even if the pattern is distorted during formation, it will not be formed on the picture element electrode. There is no contact with the gate and source path lines 4.5, and therefore no leakage occurs during liquid crystal driving and no display defects occur. Furthermore, since the pattern is transparent, light is not blocked, and the aperture ratio of the picture element electrode 22 is improved, allowing high-quality display. Further, as in the case of FIG. 1, the identification number 30 can be easily visually confirmed with appropriate contrast, and defective parts can be repaired appropriately. In other words, the identification number 30 makes it possible to provide a liquid crystal display device with high display quality and no display defects.

In the above embodiments, a case has been described in which the nonlinear element that drives the active matrix is a thin film transistor, but the present invention can also be applied to a case where the nonlinear element that drives the active matrix is a diode or the like. Furthermore, it goes without saying that the present invention is not limited to the illustrated embodiment.

<Effects of the Invention> As is clear from the above description, the liquid crystal display device of the present invention is an active matrix type device equipped with a nonlinear element, and a liquid crystal display device using a punched pattern or a transparent electrode film in each picture element electrode. Since each remaining pattern has a unique identification number, there is no display defect caused by leakage due to contact with the pass line, which is the case with conventional patterns made of metal materials. The aperture ratio of the elemental electrode is improved, allowing for high-quality display, and also providing a suitable contrast with the substrate, allowing for easy identification of the identification number and immediate and appropriate repair of defective areas.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 respectively show the first embodiment of the present invention. FIG. 3 is a plan view showing an example of a second liquid crystal display device, FIG. 3 is a plan view showing a conventional liquid crystal display device, and FIG. 4 is a cross-sectional view taken along the line ■■ in FIG. 3. 1.21...Liquid crystal display device, 2.22...Picture element electrode, 3...Thin film transistor, 4...Gate pass line, 5...Source pass line, 20.30...Identification number ( (cutting pattern, leaving pattern).

Claims (2)

[Claims] (1) An active matrix liquid crystal display device equipped with a nonlinear element, characterized in that numbers are formed in each picture element electrode in a punched pattern. (2) An active matrix liquid crystal display device equipped with a nonlinear element, characterized in that numbers are formed in each picture element electrode in a pattern using a transparent electrode film.