| Summary: | 碩士 === 中華大學 === 機械與航太工程研究所 === 90 === In the paper an automatic adjustment and test system is developed to perform the adjustment and test of an optical scan module so that the manufacturing process of the scanner can be automated and the quality of the product will be in good reliability and consistency.
A test chart was scanned by the optical scan module to locate the position of the X and Y axes of the CCD camera and to adjust the focal length and magnification of the optical lens. The test chart consists of two triangle blocks and five sets of line patterns In the experiment the test chart was scanned so that the horizontal scan line passes through the central position of the triangle blocks. The position of the left triangle block and the scanning width of the two triangle blocks can then be determined and used to adjust the positions of the X and Y axes of the CCD and the Y balance of the CCD. Also the five set of line patterns on the test chart were scanned with R, G, B channels of CCD. The vertical and horizontal MTF (modulation transfer function) were then computed. Based on the computed MTF, the focal length of the lens was adjusted. In addition, the magnification of the optical lens was adjusted using the magnification difference obtained by computing the distance between the first and the fifth line pattern.
The automatic adjustment and test system was applied to production lines. The statistic figures shows that the capability of precision (Cp) and the capability of process (Cpk) are superior to manual operation.
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