Detection device of appearance of mobile phone lens

Abstract

A detection device of an appearance of a mobile phone lens is used to accurately detect and distinguish unrepairable defects caused by material flakes and repairable punctuate defects caused by others such as dust, smudginess and the like in a transparent window area of a mobile phone lens. The detection device comprises a line-scan camera, a highlight strip light source, a strip high-transmittance astigmatic lens, a frosted astigmatic lens, and a strip convex lens, wherein the line-scan camera is disposed at the top side of the mobile phone lens, and the light source is disposed at the bottom side so as to allow the backlight and the line-scan camera to be on the same axis. Although the camera and the light source are on the same axis, the camera is guaranteed to aim at the edge of the light instead of the center of the light. Therefore, it is guaranteed that not only the gray scale contrast between a defect and the edge is sufficient, but also the light intensity of a week defect is sufficient to be identified by the line-scan camera.

Description

technical field [0001] The invention relates to an appearance detection device, in particular to a detection device for effectively distinguishing point-like defects of the material itself from other defects such as dust, foreign matter and dirt in the appearance detection of the transparent window area of ​​the lens of a mobile phone. Background technique [0002] The mobile phone lens refers to the panel in front of the mobile phone display, mainly including a transparent window area and a printing area. The appearance inspection of mobile phone lenses is a very important part of the mobile phone production process. At present, all mobile phone lens factories in China use manual inspection. It is not only inefficient, but also has large human error, high missed detection rate, and cannot be quantified. However, due to the large variety of defects and the large differences in products, it is difficult to use a visual system for appearance inspection, and it cannot effecti...

AI Technical Summary

Problems solved by technology

However, since all kinds of defects appear in the form of higher gray value than the surrounding gray value, and based on the shape, only points, blocks, straight lines, curves and other defects can be distinguished, and material point defects cannot be distinguished from Other point defects of dust, dirt, etc.

[0004] In addition, the line-scan light source cannot be used as a background light source, because when the line-scan light source is directly irradiated, the line-scan camera will get an uneven image with alternating light and dark due to unevenness

However, if an ordinary backlight is used, due to the large illuminated area, when the light reaches the upper and lower surfaces of the transparent material, due to diffuse reflection, the gray value of the defect itself will be very close to the surrounding gray value and the defect cannot be highlighted, causing the defect to be invisible. Identify and miss

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