An orthogonal phase-shifting interferometry and its application to the measurement of optical plate

An optical interferometry named orthogonal phase-shifting interferometry (OPSI) was proposed. Compared with other interferometers, OPSI works well at air turbulence and complex environment. Phase recovery method was calculated by Jones matrix for measurement of optical elements surface shape and roughness. In order to control piezo-electric transducer (PZT) shifter, the property between voltage and phase of PZT shifter was calculated. Based on this interferometry, the roughness of an unknown transparent optical plate was measured. The results show that the error of peak to valley (PV) value is 0.0087λ (λ = 1064 nm) and the error of root mean square (RMS) value is 0.0006λ compared with WYKO(a commercial interferometer of Veeco),and this demonstrates the high stability and precision of the orthogonal phase-shifting interferometry.