摘 要: | A position sensor based on slit imaging is proposed and its measurement principle is described. An imaging slit is illuminated by a collimated laser beam with square-wave modulation and imaged on a detection double slit through a 4f system. A magnified image of the detection double slit is formed on a bi-cell detector. The position of the imaging slit is obtained by detecting light intensity on two parts of the hi-cell detector. In experiments, the feasibility of the sensor was verified. The repeatability was less than 40 nm.
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