半导体光子学与技术, 2006, 12 (1): 61, 网络出版: 2011-08-18
Scanning Measurement Method of Dispersion Mini-spot by Quadrant Photodetector
Scanning Measurement Method of Dispersion Mini-spot by Quadrant Photodetector
摘要
Abstract
Quadrant photodetector is a new type position detector, which has already been applied to many fields such as measurement, target tracking, control, laser collimation, guidance, etc. System performance is related to laser spot area received by the quadrant photodetector. The optimum linear output signal of system is gotten only when the size of laser dispersion spot is well-proportioned to the detector photosensitive area. A method to measure the mini-spot received by detector and to adjust it in real time is presented, which is based on the quadrant geometrical and optical structure, making use of tilting mirror scanning, the sequence output signal of detector is gotten, then measurement model is built with rate of signal change as characteristic variable, the radius of the laser dispersion spot and adjustable value of dispersion are calculated. The experiment result shows that the maximum error is 0.58μm in measurement range of 0.5 mm±0.1 mm.
DANG Li-ping, LIU Jun-hua, TANG Shu-gang. Scanning Measurement Method of Dispersion Mini-spot by Quadrant Photodetector[J]. 半导体光子学与技术, 2006, 12(1): 61. DANG Li-ping, LIU Jun-hua, TANG Shu-gang. Scanning Measurement Method of Dispersion Mini-spot by Quadrant Photodetector[J]. Semiconductor Photonics and Technology, 2006, 12(1): 61.