Polarization-standing-wave interferometer for displacement measurement

An optical standing-wave interferometer using a polarization technique for displacement measurement is proposed. An ultra-thin scattering plate is inserted into the optical standing-wave field, which is built by the interference of the forward- and backward-propagating light beams. By means of detecting the phase variations of the scattered light from the scattering plate with the polarization phase quadrature technique, the displacement can be determined precisely. The experimental results demonstrate that this polarization-standing-wave interferometer can measure displacement on a scale of tens of millimeters with nanometer-scale resolution. The periodic nonlinear error caused by the multi-beam interference is also detailed.