Light source regulation method for LCD glass substrate defect detection

[0014] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0015] Examples.

[0016] A light source adjustment method for defect detection of LCD glass substrates, the design process is as follows:

[0017] (1) The light source model of the LCD glass substrate defect detection system

[0018] The light source model for TFT-LCD liquid crystal screen glass substrate defect detection is shown in the figure.

[0019] Attached figure 1 , 2 Shown in is the light source lighting model for traditional LCD glass substrate defect detection. When installing the light source in the imaging system, we can only estimate the approximate position of the light source during routine operation, but cannot accurately calibrate it. When using a strip light source, the effective area with high brightness and uniform brightness in the illuminated area is similar to a long and narrow strip rectangle. If it is not adjusted, the illuminated areas of the initial reflected light source and the transmitted light source are generally prone to cross or dislocation. As attached image 3 Shown. This will cause uneven distribution of the brightness of the image collected by the camera, affect the imaging quality, and reduce the detection accuracy and accuracy of the system.

[0020] In summary, the main problem of light source adjustment for TFT-LCD liquid crystal glass substrate defect detection is to determine the reference plane where the illumination area is located and the reference line perpendicular to the direction of movement, so that the reflected light area of ​​the reflected light source and the transmitted light area of ​​the transmitted light source Overlap at the reference line and parallel to the reference line, perpendicular to the direction of movement of the moving platform.

[0021] (2) Design of light source adjustment method for liquid crystal screen glass substrate defect detection system

[0022] To adjust the illumination area, first determine the reference plane where the illumination area is and the reference line with the illumination position.

[0023] Attached Figure 4 Choose a piece of transparent flat glass, the width of the glass should be greater than the width of the test object, and the thickness of the glass should be less than 2mm to reduce errors. The plane G where the flat glass is located can be regarded as the reference plane T for the motion platform detection. Paste A4 printing paper S on both ends of the glass plane 1 , S 2 , Draw a straight line on the white paper parallel to the glass placement direction l 1 , L 2. When the glass is mounted on the moving platform, when its placement direction is perpendicular to the moving direction, the straight line L where the two line segments are located can be used as the reference line.

[0024] After placing the reference plate glass, start to adjust the reflected light source to l 1 , L 2 As a reference, adjust the position of the reflected light source until l 1 , L 2 Respectively in the light A on the paper S 1 , S 2 The center of the upper illuminated area. Afterwards, the position of the transmitted light source can be adjusted in the same way. After the adjustment is completed, it can be considered that the reflected light area and the transmitted light area overlap the reference line, and are parallel to the reference line and perpendicular to the direction of movement of the moving platform. At this time, the light source has been adjusted to the best Location, the camera can obtain high-quality and stable images.

[0025] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Anyone familiar with the technical field within the technical scope disclosed by the present invention, according to the technical solution of the present invention Equivalent replacements or changes to its inventive concept should all fall within the protection scope of the present invention.