On the linear array CCD used for measuring the long distance diffraction alignment

The measurement errors caused by the variation of incident optical intensity in measuring large-scale forms and position were analyzed when the laser diode fiber and phase plate alignment technique as well as the linear array of CCD detectors were used. Besides, the principles and characteristics of using a linear array CCD as sensor to measure the diffraction pattern of one-dimensional asymmetric phase plate were also analyzed. Based on these analyses, a method for maintaining the output peak-voltage constant of CCD signal was put forward by controlling the exposure time of CCD automatically according to the operating principle and characteristics of the linear array CCD.