A method for optically detecting liquid crystal modules

Abstract

The present invention relates to a liquid crystal module optical detection method, comprising a detection device, the detection method comprising the following steps: a first step, placing a liquid crystal module (3) on a test platform (2), and making the two have a common center; a second step, adjusting the angle of a rotating disk 4, making the irradiation angle of an excitation light source 5 pass through the center of the liquid crystal module 3, and making the light emitted by the excitation light source 5 and the liquid crystal module 3 present an angle of 30-60°, and starting a servo motor 1 to rotate; a third step, turning on a camera 7, using the camera 7 to continuously shoot, the shooting interval is 0.1 seconds per picture, and the shot images are sent to a control system, and the control system analyzes and processes the images. The device can conveniently detect the flatness of the surface of a liquid crystal module.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid crystal modules, and in particular to an optical detection method for liquid crystal modules. Background Art

[0002] With the development of technology, liquid crystal display (LCD) has become

[0003] Thin, light and low power consumption make it widely used in electronic products such as personal computers, mobile phones, televisions and monitors.

[0004] After the LCD is manufactured, it is necessary to test the flatness of its surface. Flatness detection is also called frontality detection and coplanarity detection. The flatness detection system is specially used to detect the horizontal straightness, coplanarity, gap, pin width and other indicators of the pins of various IC chips, electronic connectors and other electronic components. At present, a large number of electronic product manufacturers have begun to use machine vision inspection systems to replace the original manual inspection method. After simple settings, it can automatically identify and detect without human operation. However, the existing flatness detection device still has the disadvantage of being expensive when used, and the structure is complex, which is not conducive to large-scale production. Summary of the invention

[0005] In order to solve the above technical problems, an object of the present invention is to provide a liquid crystal module optical detection method.

[0006] The technical solution of the present invention is as follows:

[0007] A liquid crystal module optical detection method, comprising a detection device, the detection device comprising a servo motor (1), a test platform (2) driven to rotate by the servo motor (1), a liquid crystal module (3) to be detected being placed on the test platform (2), a linear excitation light source (5) for irradiating the liquid crystal module (3), and a reflection plate (8) located above the test platform (2), wherein the reflection plate (8) is provided with an array of triangular convex strips (9) of different colors, characterized in that the detection method comprises the following steps:

[0008] The first step is to place the liquid crystal module (3) on the test platform (2) so that the two have a common center;

[0009] The second step is to adjust the angle of the rotating disk (4) so ​​that the irradiation angle of the excitation light source (5) passes through the center of the liquid crystal module (3) and the light emitted by the excitation light source (5) and the liquid crystal module (3) are at an angle of 30-60 degrees, and start the servo motor (1) to rotate;

[0010] The third step is to turn on the camera (7) and use the camera (7) to continuously take pictures, with an interval of one picture per 0.1 second. The taken images are sent to the control system, and the control system analyzes and processes the images.

[0011] Furthermore,

[0012] Acquire an image, and intercept an image where the reflected light is located on a triangular convex strip;

[0013] Convert the image into grayscale mode, calculate the grayscale value of each pixel, compare the grayscale values ​​of any two adjacent pixels, if the grayscale value ratio of the two adjacent pixels is between 0.9 and 1, then the two adjacent pixels are the same type of pixels, these same type of pixels will form image points, after obtaining multiple image points, two areas are formed, one area is the image of the convex strip itself, and the other area is the image of the reflected light, and the number of pixels of the reflected light image is counted;

[0014] Outside the reflected light image, a minimum rectangle that can include the reflected light image is set, the number of all pixels in the rectangle is calculated, and the proportion of the number of pixels of the reflected light image to the number of all pixels in the rectangle is counted. If the proportion is less than 95%, it is considered that there is a protrusion in the reflected light image that exceeds the outside of the normal reflected light, and the protrusion is a point with defective flatness.

[0015] Furthermore,

[0016] In the second step, the light emitted by the excitation light source 5 is parallel to the tip of the triangular convex strip (9).

[0017] Furthermore,

[0018] The servo motor (1) is also connected to a reduction box, and the reduction box is connected to the test platform (2).

[0019] Furthermore,

[0020] The triangular convex strips (9) are arranged at intervals for painting at least two colors.

[0021] Furthermore,

[0022] The excitation light source (5) is a red laser light source.

[0023] By means of the above scheme, the present invention has at least the following advantages:

[0024] The device can conveniently detect the flatness of the surface of the liquid crystal module. When there are large defects on the surface of the liquid crystal module, the result can be conveniently known by observing the triangular convex strips. When the defects on the surface of the liquid crystal module are not large, the image can be processed by the control system to know the relevant results.

[0025] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show a certain embodiment of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 It is a schematic diagram of the structure of the detection of the present invention;

[0028] Figure 2 It is a schematic diagram of the present invention detecting normal and abnormal;

[0029] In the figure:

[0030] 1-servo motor; 2-test platform; 3-liquid crystal module; 301-defect; 4-rotating disk; 5-excitation light source; 6-guide rail; 7-camera; 8-reflection plate; 9-triangular convex strip. DETAILED DESCRIPTION

[0031] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0032] See also Figure 1, the optical detection method of liquid crystal module described in a preferred embodiment of the present invention, the hardware used in the detection method is as follows, a servo motor 1 installed on the ground, the servo motor 1 adopts a high-precision motor, a reduction box is generally connected to the driving end of the servo motor 1, and a test platform 2 is connected to the driving end of the reduction box, the test platform 2 is a flat square plate, the center of which is connected to the driving end of the reduction box, because the square plate is used to place the liquid crystal module for testing, a layer of flexible material is also pasted on the surface of the square plate, the flexible material can be a rubber pad with a thickness of 2-3mm, or a hard sponge with a thickness of 3-5mm, during the specific test, the liquid crystal module is placed on the square plate, the flexible material mainly plays two roles, one is a buffering effect, to protect the liquid crystal module, the second is to increase the friction between the square plate and the liquid crystal module, during the test, the liquid crystal module moves on the square plate. A rotating disk 4 is also provided, and the rotating disk 4 is installed diagonally above the test platform 2. The rotating disk 4 can be connected to the driving end of a motor, and the rotation of the rotating disk can be realized by the motor. An excitation light source 5 is installed on the rotating disk 4. The excitation light source 5 is a linear light source, and the excitation light source 5 is fixed on the rotating disk 4. Since the rotating disk 4 is vertically arranged, the excitation light source 5 is vertically connected to the rotating disk 4. Therefore, by adjusting the rotation angle of the rotating disk 4, the position and angle of the excitation light source 4 irradiated on the liquid crystal module 3 can be changed.

[0033] The reflective plate 8 is also included and is located above the test platform 2 . The reflective plate 8 is located directly above the test platform 2 and is arranged parallel to the test platform 2 .

[0034] A plurality of triangular convex strips 9 are arranged in a linear array on the lower surface of the reflector 8 , and different colors are arranged every other triangular convex strip 9 .

[0035] It also includes a guide rail 6, on which a camera 7 is slidably arranged, with the camera port of the camera 7 facing the reflector 8, and the camera 7 is a high-speed camera.

[0036] The present invention also includes a control system, which is connected to the servo motor 1, the motor driving the rotating disk 4, and the camera 7. The control system is not only used to control the two motors, but also can receive the image taken by the camera 7 and analyze and process the image to detect the position of the servo motor 1.

[0037] The above is the hardware device of the present invention. The specific testing method and principle of the present invention are as follows.

[0038] The first step is to place the liquid crystal module 3. It is necessary to ensure that when the liquid crystal module 3 is on the test platform 2, the centers of the two coincide. Since the liquid crystal module 3 is generally square and the test platform 2 is square, it is only necessary to ensure that the distances from the two relatively arranged sides of the liquid crystal module 3 to the edges of the test platform 2 are equal to ensure that the two have a common center.

[0039] While ensuring that the two have a common center, it can also be ensured that during the rotation process, the liquid crystal module 3 always has a common center with the test platform.

[0040] The second step is to adjust the angle of the rotating disk 4 so that the irradiation angle of the excitation light source 5 passes through the center of the liquid crystal module 3 and the light emitted by the excitation light source 5 is at an angle of 30-60° to the liquid crystal module 3. The servo motor 1 is started to rotate.

[0041] The excitation light source 5 emits a line light source, specifically a red laser line light source. Since the liquid crystal module 3 is planar and has a reflective effect, the device is used to detect defects on the surface of the liquid crystal module 3 and its surface flatness. After the excitation light source 5 is irradiated on the liquid crystal module 3, it will be reflected on the reflective plate 8. After reflection, the light will be reflected on the reflective plate 8. If the surface of the liquid crystal module 3 is flat, the position of the triangular ridge 9 on the reflective plate 8 will change from the normal reflection situation. Since the reflected light passes through different triangular ridges 9, it can be determined by human eye whether there is a defect on the surface of the liquid crystal module 3. If the position of the defect is relatively small, the reflected light is always on the same triangular ridge 9, then the camera 7 will be enabled and analyzed using the control system.

[0042] The third step is to turn on the camera 7 and use the camera 7 to continuously shoot, with an interval of one shot per 0.1 second. The shot images are sent to the control system, and the control system analyzes and processes the images. The specific analysis process is as follows.

[0043] Do the following processing on any image:

[0044] Acquire an image, and intercept an image where the reflected light is located on a triangular convex strip;

[0045] Convert the image into grayscale mode, calculate the grayscale value of each pixel, and compare the grayscale values ​​of any two adjacent pixels. If the grayscale value ratio of two adjacent pixels is between 0.9 and 1, then the two adjacent pixels are the same type of pixels. These pixels of the same type will form image points. After obtaining multiple image points, two areas are formed, one of which is the image of the convex strip itself, and the other is the image of the reflected light. Count the number of pixels in the reflected light image.

[0046] Outside the reflected light image, a minimum rectangle that can include the reflected light image is set, the number of all pixels in the rectangle is calculated, and the proportion of the number of pixels of the reflected light image to the number of all pixels in the rectangle is counted. If the proportion is less than 95%, it is considered that there is a protrusion in the reflected light image that exceeds the outside of the normal reflected light, and the protrusion is a point with defective flatness.

[0047] This device has the following advantages:

[0048] The device can conveniently detect the flatness of the surface of the liquid crystal module. When there are large defects on the surface of the liquid crystal module, the result can be conveniently known by observing the triangular convex strips. When the defects on the surface of the liquid crystal module are not large, the image can be processed by the control system to know the relevant results.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for optically inspecting a liquid crystal module, comprising a detection device, the detection device comprising a servo motor (1), a test platform (2) driven to rotate by the servo motor (1), a liquid crystal module (3) to be inspected being placed on the test platform (2), a linear excitation light source (5) for irradiating the liquid crystal module (3), and a reflector (8) located above the test platform (2), wherein the reflector (8) is provided with an array of triangular convex strips (9) of different colors, characterized in that: The detection method includes the following steps: The first step is to place the liquid crystal module (3) on the test platform (2) so that the two have a common center; The second step is to adjust the angle of the rotating disk (4) so ​​that the irradiation angle of the excitation light source (5) passes through the center of the liquid crystal module (3) and the light emitted by the excitation light source (5) and the liquid crystal module (3) are at an angle of 30-60 degrees, and start the servo motor (1) to rotate; The third step is to turn on the camera (7) and use the camera (7) to continuously take pictures, with an interval of one picture per 0.1 second. The taken pictures are sent to the control system, and the control system analyzes and processes the pictures; The third step is specifically as follows: Acquire an image, and intercept an image where the reflected light is located on a triangular convex strip; Convert the image into grayscale mode, calculate the grayscale value of each pixel, compare the grayscale values ​​of any two adjacent pixels, if the grayscale value ratio of the two adjacent pixels is between 0.9 and 1, then the two adjacent pixels are the same type of pixels, these same type of pixels will form image points, after obtaining multiple image points, two areas are formed, one area is the image of the convex strip itself, and the other area is the image of the reflected light, and the number of pixels of the reflected light image is counted; Outside the reflected light image, a minimum rectangle that can include the reflected light image is set, the number of all pixels in the rectangle is calculated, and the proportion of the number of pixels of the reflected light image to the number of pixels in the rectangle is counted. If the proportion is less than 95%, it is considered that there is a protrusion in the reflected light image that exceeds the outside of the normal reflected light, and the protrusion is a point with defective flatness; In the second step, the light emitted by the excitation light source (5) is parallel to the tip of the triangular convex strip (9).

2. The method for optically inspecting a liquid crystal module according to claim 1, characterized in that: The servo motor (1) is also connected to a reduction box, and the reduction box is connected to the test platform (2).

3. The method for optically inspecting a liquid crystal module according to claim 1, characterized in that: The triangular convex strips (9) are arranged at intervals for painting at least two colors.

4. The method for optically inspecting a liquid crystal module according to claim 1, wherein: The excitation light source (5) is a red laser light source.

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