Optic Grating Sensor Based High Precision Straight-line Displacement Measurement and Its Error Analysis

摘要

To accomplish precision straight-line and angular displacement measurement, the principle and realizing methods on the basis of optical grating are analyzed in detail. A new quadruple frequency circuit and its relative analogous circuit are designed, including scaling circuit of optical grating sensor and display module. For realizing displacement measurement in nanometer-size, corresponding software system of type-51 single chip microcomputer as a control core has designed accordingly. Output display and optic grating signal processing in real-time are achieved. Finally, the error source of system is discussed and error analysis is carried out in this paper. The experimental results show that system can realize high precision measurement and can be used in fine measuring instrument for high precision displacement measurement.