JP2004226886A - Output checker of liquid crystal display driving system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of colors to be checked and to attain reduction of the checking time, easy decision, easy automation and reduction of a display region, in an output checker of a liquid crystal display driving system. <P>SOLUTION: The output checker of the liquid crystal display driving device 9 checking whether the output colors of the liquid crystal display driving device 9 driving luminosities of three primary colors R, G and B of an image with signals of respective N (N means an integer) bits are normal is provided with a liquid crystal display pattern generating circuit 6 outputting a liquid crystal display pattern for inspection of N×3 kinds wherein only one of the respective bits for the respective R, G and B are made ON and an LCD 11 displaying a check pattern by a driving signal of the liquid crystal display driving device 9 to be an object inputting the output of the liquid crystal display pattern generating circuit 6 and outputting the driving signal. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an output inspection device for a liquid crystal display driving device for inspecting whether or not an output color of a liquid crystal display driving device is normal.
[0002]
[Prior art]
Currently, after mounting circuit components on a liquid crystal display driving substrate, an inspection is performed to determine whether or not the output color is normal. For example, a color liquid crystal display driving device of a mobile phone is a COF (chip on flexible printed circuit) in which a surface mount component is mounted on a flexible printed circuit (flexible printed circuit). The color is a mixture of three primary colors of RGB, and there are 256 types of lightness of 8 bits each. Therefore, conventionally, 256 patterns were displayed for each of RGB, and the inspection was performed with the naked eye.
[0003]
[Problems to be solved by the invention]
However, discrimination of all combinations of lightness bits required skill and inspection took a long time. Further, since the inspection is an artificial inspection, there is a possibility that a defect is missed.
[0004]
[Means for Solving the Problems]
The output inspection device of the liquid crystal display driving device of the present invention has been made in view of the above point, and the output color of the liquid crystal display driving device which drives the brightness of the three primary colors RGB of the image by N (N is a positive integer) bit signals respectively. In the output inspection device of the liquid crystal display drive device for inspecting whether or not is normal,
A pattern generation circuit for outputting N × 3 kinds of liquid crystal display patterns for inspection in which only one of the bits is turned on for each of RGB, and a test object for inputting an output of the pattern generation circuit and outputting a drive signal A display unit for displaying an inspection pattern in response to a drive signal of a liquid crystal display drive device for the object.
[0005]
As a result, the number of signals to be inspected can be reduced, and the inspection time can be reduced, easy determination, easy automation, and reduction of the display area can be achieved.
[0006]
A storage unit for storing the N × 3 types of reference colors; a detection unit for detecting the N × 3 types of colors displayed on the display unit; and a color detected by the detection unit and the storage unit. Control means for comparing the stored reference color with the reference color and outputting a determination result.
[0007]
This automation makes it possible to prevent a defect from being overlooked artificially.
[0008]
Further, the detecting means takes an image of the test pattern displayed on the display unit in black and white binary, and the control means judges the test pattern in black and white binary. Thereby, an inexpensive device can be supplied.
[0009]
The detecting means includes an irradiating means for irradiating the inspection pattern displayed on the display section with white. As a result, the brightness level can be made uniform for RGB.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
[0011]
FIG. 1 is a block diagram showing a main part of the embodiment. The control circuit (1) controls each unit based on a program stored in the ROM (2). The RAM (3) stores information necessary for the operation of the control circuit (1), for example, a reference color. The display unit (4) displays an inspection operation and a message related to the inspection. The inspection operation is performed on the input unit (5).
[0012]
A liquid crystal display driving device (9) as an object to be inspected is connected to a first connection portion (8) and a second connection portion (10). Under the control of the control circuit (1), the liquid crystal display pattern generation circuit (6) outputs the test liquid crystal display pattern to the liquid crystal display driving device (9) via the first connection portion (8). The IC power supply (7) supplies power to the liquid crystal display driving device (9) via the first connection section (8).
[0013]
The liquid crystal display driving device (9) outputs the test liquid crystal display pattern based on the output of the liquid crystal display pattern generation circuit (6) to the LCD (11) via the second connection portion (10). The LCD (11) displays a test liquid crystal display pattern based on the output of the liquid crystal display driving device (9), the camera (12) takes an image of the pattern, and outputs the image information to the control circuit (1).
[0014]
The control circuit (1) analyzes the imaging information output from the camera (12) and identifies the color of each pixel of the LCD (11). Then, the result is compared with the reference color stored in the RAM (3), and the result is displayed on the display unit (4).
[0015]
The above configuration will be described in detail. The liquid crystal display driving device (9) of the present embodiment is used for color display of a mobile phone device. The color of the color is a mixture of three primary colors of RGB, and there are 256 types of lightness of 8 bits each. Therefore, the color designation signal for each pixel is 8 bits of R, 8 bits of G, and 8 bits of B, for a total of 24 bits. The liquid crystal display pattern generation circuit (6) of the present invention outputs 8 × 3 types of inspection liquid crystal display patterns in which only one of the bits is turned on for each of RGB.
[0016]
FIG. 2 shows a pixel unit pattern displayed on the LCD (11). Only the first bit of brightness as R is “1” (here, 1 is turned ON), and signals of G and B are all output as “0” to the pixel of R0. The G0 pixel outputs a signal in which only the first bit of brightness as G is "1" and the brightness of R and B is all "0". The B0 pixel outputs a signal in which only the first bit of brightness as B is "1" and the brightness of R and G is all "0". In addition, only the seventh bit of the brightness as G is "1" to the pixel of G6, and the signals of R and B are all "0". In this way, only 24 bits are displayed in a total of 24 pixels, with only one bit being "1" and the other bits being "0" signals.
[0017]
The camera (12) has a white LED light source and irradiates the LCD (11) to image 24 pixels in black and white binary. Since only one color of RGB is displayed on the 24 pixels to be inspected, a binary brightness determination may be used. According to an experiment by the inventor, when a halogen is used as a light source, since the halogen illumination has a wavelength close to red, the brightness level in the case of black and white binarization of B (blue) is R (red) or G (green). It becomes 1/3. Therefore, the present invention uses a white light source to achieve a uniform brightness level of RGB.
[0018]
The RAM (3) stores reference black and white binary brightness information. The control circuit (1) compares the brightness of the 24 pixels captured by the camera (12) with a reference value stored in the RAM (3). The display unit (4) displays whether or not the brightness of each pixel matches. Based on the result displayed on the display unit (4), the user can make a pass / fail judgment and assume a defective portion in the case of a defect.
[0019]
Conventionally, 256 colors have been displayed for each RGB as a pattern for inspection. The present invention focuses on the types of signals output by the liquid crystal display driving device (9), and displays 8 × 3 types of inspection patterns in which only one of each bit of brightness is turned on for each of RGB. . As a result, the number of colors to be inspected is reduced, so that the inspection time can be reduced, easy determination, easy automation, and reduction of the display area can be achieved. In the above-described example, the brightness is determined by imaging in black and white binary. However, even if the image is captured in color and the color is determined, this effect can be obtained. In addition, even if the judgment is made manually, there is an effect of shortening the inspection time and making the judgment easy.
[0020]
Further, since it is a single color without a mixed color of RGB, it is possible to determine the brightness of black and white binary, and it is possible to supply an inexpensive device.
[0021]
Although the liquid crystal display driving device in the above-described example is a COF, it is not limited to the material of the substrate, and may be another substrate.
[0022]
In the above-described pattern, one color is displayed on one pixel, but one color may be displayed on a plurality of pixels.
[0023]
【The invention's effect】
Conventionally, all brightness colors are displayed for each of RGB as a pattern for inspection. The present invention focuses on the types of signals output by the liquid crystal display driving device, and displays 8 × 3 types of inspection patterns in which only one of each bit of brightness is turned on for each of RGB. As a result, the number of colors to be inspected can be reduced, and the inspection time can be shortened, easy determination, easy automation, and reduced display area can be achieved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a main part of the present invention.
FIG. 2 is a diagram showing an inspection pattern displayed on an LCD.
[Explanation of symbols]
1 control circuit 6 liquid crystal display pattern generation circuit 9 liquid crystal display driving device 11 LCD
12 Camera

Claims (4)

In an output inspection device of a liquid crystal display driving device for inspecting whether or not an output color of a liquid crystal display driving device for driving the brightness of the three primary colors RGB of an image with N (N is a positive integer) bit signals, respectively,
A pattern generation circuit that outputs N × 3 kinds of inspection liquid crystal display patterns in which only one of the bits is turned on for each of RGB, and a test object that inputs an output of the pattern generation circuit and outputs a drive signal A display unit for displaying an inspection pattern in accordance with a drive signal of the liquid crystal display driving device for an object. Storage means for storing the N × 3 types of reference colors; detection means for detecting the N × 3 types of colors displayed on the display unit; and the colors detected by the detection means and stored in the storage means 2. An output inspection device for a liquid crystal display driving device according to claim 1, further comprising control means for outputting a judgment result by comparing the output with a reference color. 3. The liquid crystal display driving device according to claim 2, wherein the detection unit captures an image of the test pattern displayed on the display unit in black and white binary, and the control unit determines the test pattern in black and white binary. Output inspection device. 4. The output inspection device for a liquid crystal display driving device according to claim 3, wherein the detection unit includes an irradiation unit that irradiates the inspection pattern displayed on the display unit with white.

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