Modeling and suppressing the wavefront degeneration in a CGH interferometric null test

The computer-generated hologram (CGH) enables the ultra-high accuracy of surface measurement but causes the wavefront degeneration in the optical system. In this article, we give a high-accuracy analytical simulation of the wavefront degeneration in null test by the elliptical Gaussian model. We propose an analytical expression of instrumental transfer function (ITF) for the CGH null test without knowing the phase distribution of CGH, which gives an efficient instruction to suppress the wavefront degeneration. The ITF of the interferometric null test for a O3m aspheric mirror can be optimized from 0 to 0.65 at 0.4 Nyquist frequency. (c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

In this article, an analytical simulation of wavefront degeneration in computer-generated hologram (CGH) null test is presented using the elliptical Gaussian model. An analytical expression of instrumental transfer function (ITF) is proposed to suppress the wavefront degeneration without knowing the phase distribution of CGH.