LCD protective film surface interference detection device

Abstract

The invention discloses an LCD protective film surface interference detection device, which comprises a detection platform, a plurality of low-angle light sources and a detection support, the detection platform is used for placing an LCD protective film to be detected, the low-angle light sources are arranged at adjacent positions of the detection platform, and the low-angle light sources are located above the LCD protective film. A camera and a rotary driving mechanism are arranged on the detection support, a lens of the camera is arranged above the LCD protective film, the rotary driving mechanism comprises a vertically arranged driving shaft, a polariscope support is fixed to the lower end of the driving shaft, the polariscope support is perpendicular to the driving shaft, a polariscope is fixed to the polariscope support, and the low-angle light source is used for obliquely irradiating the LCD protective film. The rotation driving mechanism is used for driving the polariscope support to rotate by a preset angle in the horizontal direction until the polariscope is aligned with the lens of the camera. The device is helpful for detecting stains on the membrane and internal stains, and has the characteristics of simple structure, easiness in control, low application cost and the like.

Description

Technical Field

[0001] The invention relates to a detection device for LCD products, in particular to a detection device for surface interference of an LCD protective film. Background Art

[0002] In the production process of LCD, in order to prevent the polarizer from being scratched and stained, a protective film needs to be covered on the polarizer of the LCD substrate for surface protection, thereby reducing defective LCD products. However, in actual applications, the image feature information obtained by the camera for stains on the protective film and stains inside the LCD is similar, and it is difficult to distinguish the two through visual algorithms, which can easily lead to missed detection or false detection. In addition, the method of adding a depth camera can distinguish between dirt on the LCD surface protective film and stains inside the LCD, but such cameras are expensive and have low detection efficiency, making them difficult to be widely used in actual production. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide an LCD protective film surface interference detection device which is helpful for detecting stains on and inside the film and has a simple structure, is easy to control and has a low application cost, in view of the deficiencies of the prior art.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0005] A device for detecting interference on the surface of an LCD protective film comprises a detection platform, a plurality of low-angle light sources and a detection bracket, wherein the detection platform is used for placing an LCD protective film to be detected, the low-angle light source is arranged adjacent to the detection platform, and the low-angle light source is located obliquely above the LCD protective film, the detection bracket is provided with a camera and a rotation drive mechanism, the lens of the camera is arranged above the LCD protective film, the rotation drive mechanism comprises a vertically arranged driving shaft, a polarizer bracket is fixed at the lower end of the driving shaft, and the polarizer bracket is arranged perpendicular to the driving shaft, a polarizer is fixed on the polarizer bracket, the low-angle light source is used for obliquely irradiating the LCD protective film, and the rotation drive mechanism is used for driving the polarizer bracket to rotate in a horizontal direction by a preset angle until the polarizer is aligned with the lens of the camera.

[0006] Preferably, four low-angle light sources are included, and the four low-angle light sources together form a square light source assembly.

[0007] Preferably, the low-angle light source includes an elongated support and an elongated lamp head, and two adjacent low-angle light sources are fixedly connected by an L-shaped block, the two ends of the elongated support are respectively fixedly connected to the L-shaped block, and the two ends of the elongated lamp head are respectively rotatably connected to the L-shaped block.

[0008] Preferably, a light blocking plate is fixed to the top end of the long strip lamp holder, and a bending portion is formed at one end of the light blocking plate extending toward the inner side of the square light source assembly, and the bending portion is bent obliquely downward.

[0009] Preferably, the polarizer bracket is in the shape of a plate, an end of the polarizer bracket away from the driving shaft is formed with an opening, and the polarizer covers the opening.

[0010] Preferably, a fixing ring and a fixing circle are formed at the upper and lower ends of the opening, respectively, and the polarizer is clamped between the fixing ring and the fixing circle.

[0011] Preferably, an in-place sensing switch is fixed on the detection bracket, and a trigger plate is fixed to the upper end of the driving shaft, and the trigger plate is aligned with the sensing area of ​​the in-place sensing switch. When the driving shaft is rotated until the polarizer is aligned with the lens of the camera, the trigger plate enters the sensing area of ​​the in-place sensing switch to cause the in-place sensing switch to generate an electrical signal.

[0012] In the LCD protective film surface interference detection device disclosed in the present invention, the detection platform can clamp and fix the LCD protective film by setting a fixture, and at the same time, the low-angle light source is set at an angle above the LCD protective film. The low-angle light source provides fill light for the product by obliquely irradiating the LCD protective film. During specific detection, the low-angle light source is first lit, and then the rotation drive mechanism drives the polarizer bracket to rotate a preset angle in the horizontal direction until the polarizer is aligned with the camera lens. Under the action of the polarizer, the image feature information below the polarizer in the LCD product is suppressed, so that the camera can accurately capture the scratches or dirty positions on the protective film, which helps to distinguish between stains on the film and internal stains. At the same time, the present invention has a simple structure and is easy to realize fill light control and rotation motion control. In addition, the present invention does not need to use an expensive depth camera, so the application cost is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a structural diagram of the LCD protective film surface interference detection device of the present invention; Figure 2 This is an exploded view of a square light source assembly; Figure 3 To test the structure of the bracket, camera, rotation drive mechanism and polarizer bracket Figure 1 ; Figure 4 To test the structure of the bracket, camera, rotation drive mechanism and polarizer bracket Figure 2 . DETAILED DESCRIPTION

[0014] The present invention is described in more detail below with reference to the accompanying drawings and embodiments.

[0015] The present invention discloses a device for detecting interference on the surface of an LCD protective film. Figures 1 to 4 As shown, it includes a detection platform 1, multiple low-angle light sources 2 and a detection bracket 3, the detection platform 1 is used to place the LCD protective film 100 to be detected, the low-angle light source 2 is arranged adjacent to the detection platform 1, and the low-angle light source 2 is located obliquely above the LCD protective film 100, the detection bracket 3 is provided with a camera 4 and a rotation drive mechanism 5, the lens of the camera 4 is arranged above the LCD protective film 100, the rotation drive mechanism 5 includes a vertically arranged driving shaft 50, a polarizer bracket 6 is fixed to the lower end of the driving shaft 50, and the polarizer bracket 6 is arranged perpendicular to the driving shaft 50, a polarizer 7 is fixed to the polarizer bracket 6, the low-angle light source 2 is used to obliquely irradiate the LCD protective film 100, and the rotation drive mechanism 5 is used to drive the polarizer bracket 6 to rotate a preset angle in the horizontal direction until the polarizer 7 is aligned with the lens of the camera 4.

[0016] In the above structure, the detection platform 1 can clamp and fix the LCD protective film 100 by setting a fixture, and at the same time, the low-angle light source 2 is set obliquely above the LCD protective film 100. The low-angle light source 2 obliquely illuminates the LCD protective film 100 to fill in the light for the product. During the specific detection, the low-angle light source 2 is first lit, and then the rotation drive mechanism 5 drives the polarizer bracket 6 to rotate a preset angle in the horizontal direction until the polarizer 7 is aligned with the lens of the camera 4. Under the action of the polarizer 7, the image feature information below the polarizer in the LCD product is suppressed, so that the camera 4 can accurately capture the scratches or dirty positions on the protective film, which is helpful to distinguish between stains on the film and internal stains. At the same time, the present invention has a simple structure and is easy to realize fill light control and rotation motion control. In addition, the present invention does not need to use an expensive depth camera, so the application cost is lower.

[0017] To achieve uniform light distribution, see Figure 2 This embodiment includes four low-angle light sources 2, and the four low-angle light sources 2 together form a square light source assembly.

[0018] As a preferred embodiment, the low-angle light source 2 includes a long strip support 20 and a long strip lamp holder 21. Two adjacent low-angle light sources 2 are fixedly connected by an L-shaped block 22. The two ends of the long strip support 20 are respectively fixedly connected to the L-shaped block 22, and the two ends of the long strip lamp holder 21 are respectively rotatably connected to the L-shaped block 22. The L-shaped block 22 connects and fixes the two low-angle light sources 2 that are perpendicular to each other. Figure 2 An L-shaped block 22 is respectively provided at the four corners of the square light source assembly. With the action of the four L-shaped blocks 22, the four low-angle light sources 2 can be enclosed and fixed.

[0019] In this embodiment, a light shielding plate 23 is fixed to the top of the long strip lamp head 21, and a bending portion 24 is formed at one end of the light shielding plate 23 extending to the inner side of the square light source assembly, and the bending portion 24 is bent obliquely downward. The function of the light shielding plate 23 is to block glare, and at the same time, the bending portion 24 is extended obliquely downward to further reduce the light diffused outward, thereby improving the shooting effect of the camera 4.

[0020] See also Figure 3 and Figure 4 In the present embodiment, the polarizer bracket 6 is in the shape of a plate, an end of the polarizer bracket 6 away from the driving shaft 50 is formed with an opening 60 , and the polarizer 7 covers the opening 60 .

[0021] In order to reliably fix the polarizer 7 to the opening 60, in this embodiment, a fixing ring 61 and a fixing circle 62 are respectively formed at the upper and lower ends of the opening 60, and the polarizer 7 is clamped between the fixing ring 61 and the fixing circle 62. In practical applications, the fixing ring 61 and the fixing circle 62 can be assembled by means of snap connection or screw connection.

[0022] In order to detect the alignment of the polarizer 7 and the lens of the camera 4, in the present embodiment, an in-place sensing switch 52 is fixed on the detection bracket 3, and a trigger plate 53 is fixed to the upper end of the driving shaft 50. The trigger plate 53 is aligned with the sensing area of ​​the in-place sensing switch 52. When the driving shaft 50 is rotated until the polarizer 7 is aligned with the lens of the camera 4, the trigger plate 53 enters the sensing area of ​​the in-place sensing switch 52 to cause the in-place sensing switch 52 to generate an electrical signal.

[0023] In the above structure, by providing the in-position sensing switch 52 and the triggering plate 53, the rotation of the driving shaft 50 can be detected, thereby ensuring that the polarizer 7 is accurately aligned with the lens of the camera 4. Specifically, the in-position sensing switch 52 can be an infrared tube sensor, and the triggering plate 53 can be a semicircular shielding plate.

[0024] Before detection, this embodiment first controls the stepper motor to rotate the polarizer assembly to the bottom of the lens, adjusts the polarizer grating direction to make it orthogonal to the polarizer grating direction on the LCD, turns on the low-angle light source and rotates the polarizer device during detection, and the light from the low-angle light source irradiates the surface of the object's LCD protective film and is reflected by the polarizer and then imaged by the camera, and the light irradiated at a low angle to the bottom of the LCD polarizer passes through the LCD polarizer and the polarizer and enters the camera for imaging. Due to the orthogonal characteristics of the LCD polarizer and the polarizer grating direction, the light from the bottom of the LCD polarizer that enters the camera is suppressed, and the imaged data is handed over to the image analysis system to obtain interference information on the LCD protective film.

[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the technical scope of the present invention should be included in the scope of protection of the present invention.

Claims

1. A device for detecting surface interference of an LCD protective film, characterized in that: The invention comprises a detection platform (1), a plurality of low-angle light sources (2) and a detection bracket (3); the detection platform (1) is used to place an LCD protective film (100) to be detected; the low-angle light sources (2) are arranged adjacent to the detection platform (1), and the low-angle light sources (2) are located obliquely above the LCD protective film (100); the detection bracket (3) is provided with a camera (4) and a rotation drive mechanism (5); the lens of the camera (4) is arranged above the LCD protective film (100); the rotation drive mechanism (5) is arranged on the detection platform (1); The structure (5) comprises a vertically arranged driving shaft (50), a polarizing mirror bracket (6) being fixed to the lower end of the driving shaft (50), and the polarizing mirror bracket (6) being arranged perpendicularly to the driving shaft (50), a polarizing mirror (7) being fixed to the polarizing mirror bracket (6), the low-angle light source (2) being used for obliquely irradiating the LCD protective film (100), and the rotating driving mechanism (5) being used for driving the polarizing mirror bracket (6) to rotate at a preset angle in a horizontal direction until the polarizing mirror (7) is aligned with the lens of the camera (4).

2. The LCD protective film surface interference detection device according to claim 1, characterized in that: It comprises four low-angle light sources (2), which are combined to form a square light source component.

3. The LCD protective film surface interference detection device according to claim 2, characterized in that: The low-angle light source (2) comprises a long strip support (20) and a long strip lamp holder (21), and two adjacent low-angle light sources (2) are fixedly connected via an L-shaped block (22), the two ends of the long strip support (20) are respectively fixedly connected to the L-shaped block (22), and the two ends of the long strip lamp holder (21) are respectively rotatably connected to the L-shaped block (22).

4. The LCD protective film surface interference detection device according to claim 3, characterized in that: A light blocking plate (23) is fixed to the top end of the long strip lamp holder (21); one end of the light blocking plate (23) extending toward the inside of the square light source assembly is formed with a bending portion (24); the bending portion (24) is bent obliquely downward.

5. The LCD protective film surface interference detection device according to claim 1, characterized in that: The polarizer bracket (6) is in the shape of a flat plate, and an opening (60) is formed at one end of the polarizer bracket (6) away from the driving shaft (50), and the polarizer (7) covers the opening (60).

6. The LCD protective film surface interference detection device according to claim 5, characterized in that: A fixing ring (61) and a fixing circle (62) are respectively formed at the upper and lower ends of the opening portion (60), and the polarizer (7) is clamped between the fixing ring (61) and the fixing circle (62).

7. The LCD protective film surface interference detection device according to claim 1, characterized in that: An in-position sensing switch (52) is fixed on the detection bracket (3), and a trigger sheet (53) is fixed on the upper end of the driving shaft (50). The trigger sheet (53) is aligned with a sensing area of ​​the in-position sensing switch (52). When the driving shaft (50) is rotated until the polarizing filter (7) is aligned with the lens of the camera (4), the trigger sheet (53) enters the sensing area of ​​the in-position sensing switch (52), so that the in-position sensing switch (52) generates an electrical signal.

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