Measurement error analysis on interference testing

When an optical element is tested, the structure parameters and the surface errors of the interference system will influence the test result deeply. It is necessary to design the reasonable optical system to obtain the surface shape accurately. In this paper, the influences of the collimated lens, the imaging lens and the reference surface on the interferometric testing are analyzed, the relationship between the measurement error and system structures are built, and the optimum design is introduced to improve the test precision.