Optical mixing errors in a fiber-optic coupled heterodyne interferometer
نویسندگان
چکیده
A lightweight and electrically passive interferometer is demanded by a number of applications for precision metrology such as machine tool metrology and on-machine feedback [1]. To satisfy these requirements, a fiber-optic coupled heterodyne displacement measuring Michelson interferometer (FIDMI) shown in Fig.1 has been developed in the Center of Precision Metrology (CPM) at the University of North Carolina at Charlotte (UNCC). In FIDMI shown in Fig.2, the two orthogonal linearly polarized light components with slightly different frequencies are coupled into the interferometer with a polarization-maintaining (PM) fiber [2] to separate the application environment from the laser head. The primary limitation of accuracy encountered with a fiber-coupled heterodyne interferometer is the polarization mixing of the input beam components.
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