Determination of surface profiles of transparent plates by means of laser interferometry with wavelength tuning

摘要: Abstract An interferogram obtained from a transparent plate contains information about the profiles of both surfaces plate. This can be extracted by processing fringe patterns measured at different wavelengths. The conventional Fourier analysis applied to solve such problems for set restricted number is quite sensitive error detuning wavelength shifting and suffers interference noise. study proposes method finding surface using series phase shifts caused changes. data treatment based on analytical approach describing spatial distributions irradiance in patterns. results show that proposed feasible. experimental setup used herein was Fizeau interferometer with tunable laser. A glass approximately 1 cm thick as test sample. According results, root mean square (RMS) errors determining did not exceed 2.3 nm.