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Recently, the High Power Laser Component Technology and Engineering Department of the Shanghai Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, has made new progress in the research on multi-surface profile measurement of optical components . The relevant results were published in Optics and Lasers in Engineering under the title “ Surface profile measurement of transparent parallel plates by multi-scale analysis phase-shifting interferometry (MAPSI) ” .

In the multi-surface shape measurement of optical components, the traditional Fourier phase shift interferometry ( FTPSI , ZygoCorp. ) mainly reconstructs the optical surface profile accurately by using Fourier transform . This measurement method also has many limitations, such as high requirements for laser indicators , long-term acquisition of a large number of interference patterns, which makes the measurement results greatly affected by environmental vibration , and requires users to input precise cavity length .

To address these issues, the researchers proposed Multi-scale Analysis Phase-shifting Interferometry ( MAPSI ), which showed excellent performance. The core of this technology is to achieve accurate frequency analysis and high-precision wavefront reconstruction during wavelength tuning and phase shifting through carefully designed phase shifting steps and sampling numbers, effectively avoiding the common problems of insufficient sampling and spectrum shift in traditional multi-surface interferometry testing. Experimental results show that compared with FTPSI , MAPSI only requires fewer image sampling (about 1/6~1/4 of FTPSI ) to achieve high measurement repeatability of wavefront reconstruction. Its PV measurement repeatability and RMS measurement repeatability are better than 0.055λ and 0.012λ respectively . MAPSI not only significantly reduces the requirements for the laser tuning range and reduces the number of interferograms collected, but also its measurement results are independent of the accuracy of the cavity length input by the user, greatly improving the convenience of measurement. This work is of great significance in the multi-surface measurement of optical components.