JPH0444493A - Detector for defect of color liquid crystal panel - Google Patents

Abstract

PURPOSE:To automate the inspection and to reduce an inspection time by dividing a display screen of a color liquid crystal panel into plural picture element groups, calculating a difference of a luminance level between a picture element included in each picture element group and each picture element corresponding to a standard picture element group and displaying only the picture element whose absolute value of the difference is a prescribed value or over. CONSTITUTION:A display screen of a color liquid crystal panel 100 is divided into plural picture element groups 120. At first the data of a 1st picture element group 120 is written in a memory section 10 from a CCD camera 60 via a generating input output section 70 and the data and data relating to a standard picture element group 120A without a defect with same pattern are fed to an arithmetic section 20, a difference of a luminance level between each picture element of the picture element group 120 written in the memory section 10 and each picture element corresponding to a standard picture element group 120A is calculated by the arithmetic section 20 and the data being the absolute value of the difference of the luminance levels is written in the memory section 10. In this case, the data of the picture element group 120 and the data of the absolute value are replaced. A picture element 111 with a defect is displayed on a monitor section 40. The similar processing is implemented to all the picture element groups 120 and the check over the entire display screen is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a detection device for detecting defects in picture elements of a color liquid crystal panel.

<Conventional technology> Conventional detection of pixel defects in color liquid crystal panels is as follows:
This method takes advantage of the fact that defective picture elements have an extremely lower or higher brightness level than normal picture elements.

That is, this is done by turning on a color liquid crystal panel and visually observing the display surface of the panel to find a portion where the brightness level is different from the surrounding area.

<Problems to be Solved by the Invention> However, the conventional detection of pixel defects by visual inspection by an operator has the following problems.

■Unable to detect subtle defects.

■It is difficult to shorten inspection time.

■Inspection standards vary depending on the operator.

■As it requires excessive attention and concentration from the operator,
There is a lot of physical and mental fatigue.

■Therefore, defects may be overlooked.

The present invention was devised in view of the above circumstances, and an object of the present invention is to provide a defect detection device for a color liquid crystal panel that can automatically detect defects in picture elements of a color liquid crystal panel.

Means for Solving the Problems> A defect detection device for a color liquid crystal panel according to the present invention divides the display surface of a color liquid crystal panel into a plurality of picture element groups, and detects defects in picture elements included in the picture element groups. A defect detection device for a color liquid crystal panel that inspects the presence or absence of defects in all picture elements of a color liquid crystal panel by inspecting the presence or absence of defects, the device comprising: a lighting section for lighting the color liquid crystal panel; A memory section in which data of a standard pixel group in which defect-free pixels are arranged is stored in advance, and a luminance level of each pixel included in the pixel group and each corresponding pixel of the standard pixel group. and a monitor section that displays only picture elements for which the absolute value is equal to or greater than a predetermined value.

Effect> First, the data of the first picture element group is written to the memory section. This data and data regarding the standard picture element group are sent to a calculation section, and the difference in luminance level between both data is calculated in the calculation section.

Next, data of the absolute value of the difference in brightness levels is written into the memory section. Here, only defective picture elements are displayed on the monitor section.

Once the data related to the first picture element group has been rewritten in the memory section, the second picture element group is inspected.
Rewrite the data in the same way.

Completion of inspection of all picture element groups means that inspection of the entire display surface of the color liquid crystal panel has been completed, so the next color liquid crystal panel is inspected.

<Example> Hereinafter, an example according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a defect detection device for a color liquid crystal panel according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a standard picture element group, and FIG. 3 is a picture of a defective color liquid crystal panel. FIG. 4 is an explanatory diagram showing a defective picture element displayed on the monitor section, and FIG. 5 is a flowchart showing the operation of the defect detection apparatus for this color liquid crystal panel.

In the color liquid crystal panel 100 to be inspected by the color liquid crystal panel defect detection apparatus according to the present embodiment, the RlG, B picture elements 110R, ll0G, and 110B are arranged in a delta arrangement, that is, each of them is located at each vertex of an equilateral triangle. It is arranged like this.

Note that the picture element group 120 is the display surface of the color liquid crystal panel 100, that is, all the picture elements 110 are divided into a plurality of parts, and as shown in FIG. Picture elements 110R, 1110G, and 110B are included. Moreover, the picture element 110R11 included in the picture element group 120
It is assumed that the positions of 10G and 110B are set to be the same in all picture element groups 120. In addition, defective picture elements are indicated by the drawing number 111.

In addition, the standard picture element group 12OA is, as shown in FIG.
This is an ideal picture element group in which all the picture elements 110R, 110G, and 110B have no defects, and the picture elements 110R, 110G, and 110B are arranged in the same pattern as the picture element group 120. The standard picture element group 120A is stored in advance in the memory unit 10 as data.

This defect detection device for color liquid crystal panels focuses on the fact that the brightness levels of defective picture elements 110R, 1110G, and 110B are extremely different compared to those without defects, and calculates the difference in brightness levels to detect defective picture elements 110R1110G and 110B. The picture element 111 is specified.

The color liquid crystal panel defect detection device according to the present embodiment divides the display surface of the color liquid crystal panel 100 into a plurality of picture element groups 120, and divides the display surface of the color liquid crystal panel 100 into a plurality of picture element groups 120, and
All picture elements 110R, 110G of the color liquid crystal panel 100 are inspected for defects in IOG, 110B,
This is a device that inspects the presence or absence of defects in 110B.

Such a defect detection device for a color liquid crystal panel includes a lighting unit 30 that lights up the color liquid crystal panel 100, and a lighting unit 30 that lights up the color liquid crystal panel 100, and
Picture element 110R1110 with the same pattern as 20 and without defects
A memory unit 10 in which data of a standard picture element group 12OA in which pixels G, 110B are arranged is stored in advance, and each picture element 110R, 1110G, 110B included in the picture element group 120 and each picture corresponding to the standard picture element group 120A. Base 110R1110G
, 110B, and writes the absolute value of the difference in brightness level into the memory unit 10;
A monitor section 40 that displays only the following information is provided.

The color liquid crystal panel 100 to be inspected is placed on an X-Y table 50 and is inspected while being lit by the lighting section 30 located below the X-Y table 50. That is, by moving the color liquid crystal panel 100 in the X-Y direction by the X-Y table 50, the entire display surface is inspected as a group of picture elements 120.

Above the XY table 50, there is a CC which divides the display surface into picture element groups 120, a, and sends them to the memory section 10.
A D camera 60 is provided.

Next, the operation of this color liquid crystal panel defect detection device will be explained with reference to FIG.

First, data of the first pixel group 120 is written from the CCD camera 10 to the memory section 10 via the image input/output section 70 (S□), and this data and data regarding the standard pixel group 120A are calculated. is sent to the calculation unit 20, and the calculation unit 2
0, the difference in brightness level between both data is calculated (S
2). That is, each picture element 110R1IIOG, 110B of the picture element group 120 written in the memory section IO number, and each picture element 110R1110G, 110B of the standard picture element group 120A.
The difference in brightness level between the two is calculated.

Next, data of the absolute value of the difference in brightness levels is written into the memory unit 10 (S,). In this case, picture element group 12
0 data and absolute value data are replaced. Therefore, among the data stored in the memory unit 10, the data regarding the picture element group 120 is for each picture element 110R11.
It is only the absolute value of the difference in luminance level between each picture element of the standard picture element group 120^ in 10G and 110B.

Here, the defective picture element 111 is displayed on the monitor section 40. That is, in the picture element group 120 shown in FIG. 3, since 110G is the defective picture element 111, only that picture element 111 (IIOG) is displayed on the monitor unit 40, and the operator Call for attention.

When the rewriting of the data regarding the first picture element group 120 in the memory unit 10 is completed (S4), the second picture element group 120, that is, the adjacent picture element group 120 is inspected, and the data is similarly written. Perform rewriting.

At this time, the XY table 50 is driven by the mechanism control unit 80 so that the second picture element group 120 is located directly below the CCD camera 60.

Completion of the inspection of all the picture element groups 120 means that the inspection of the entire display surface of the color liquid crystal panel 100 has been completed, so the next color liquid crystal panel 100 is inspected (S
,).

<Effects of the Invention> The defect detection device for a color liquid crystal panel according to the present invention divides the display surface of a color liquid crystal panel into a plurality of picture element groups, and inspects the presence or absence of defects in the picture elements included in the picture element groups. A defect detection device for a color liquid crystal panel that inspects the presence or absence of defects in all picture elements of a color liquid crystal panel by detecting defects in all picture elements of a color liquid crystal panel, the device comprising: a lighting section for lighting the color liquid crystal panel; and a defect-free picture having the same pattern as the picture element group. A memory section in which data of a standard pixel group in which elements are arranged is stored in advance, and a difference in brightness level between each pixel included in the pixel group and each corresponding pixel in the standard pixel group is calculated. At the same time, it is equipped with an arithmetic unit that writes the absolute value of the difference in brightness level into the memory unit, and a monitor unit that displays only pixels for which the absolute value is greater than or equal to a predetermined value, so that subtle defects can be detected. This reduces the time required for inspection. Furthermore, since there are no differences in inspection standards depending on the operator, unlike in the past, defective picture elements will not be overlooked.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a defect detection device for a color liquid crystal panel according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a standard picture element group, and FIG. 3 is a picture of a defective color liquid crystal panel. FIG. 4 is an explanatory diagram showing a defective picture element displayed on the monitor section, and FIG. 5 is a flowchart showing the operation of the defect detection apparatus for this color liquid crystal panel. DESCRIPTION OF SYMBOLS 10... Memory part, 20... Arithmetic part, 3o... Lighting part, 40... Monitor part, 100... Color liquid crystal panel, 110R1110G, 110B... Picture element,
111...Picture element with defect, 120...Picture element group,
120^...Standard picture element group. Patent applicant Sharp Corporation Figure 1 Figure 5

Claims (1)

[Claims] (1) Divide the display surface of the color liquid crystal panel into multiple picture element groups, and inspect the presence or absence of defects in all picture elements of the color liquid crystal panel by inspecting the presence or absence of defects in the picture elements included in the picture element groups. A defect detection device for a color liquid crystal panel, comprising: a lighting unit for lighting the color liquid crystal panel; and a memory in which data of a standard picture element group in which defect-free picture elements are arranged in the same pattern as the picture element group is stored in advance. calculate the difference in brightness level between each picture element included in the picture element group and each corresponding picture element in the standard picture element group, and write the absolute value of the difference in brightness level to the memory part. 1. A defect detection device for a color liquid crystal panel, comprising: an arithmetic unit; and a monitor unit that displays only picture elements whose absolute values are greater than or equal to a predetermined value.