SEMINAR: Physics Seminar

Abstract:

Recent trends of interferometric wavefront sensing tend to focus on high precision, anti-vibration, compact, along with much more involved of electric and computer technology. The optical principles employed will not only limit the interference but also include diffraction, scattering, polarization, etc. To achieve extra high accuracy, phase-shifting point diffraction interferometry (PS-PDI) is believed to be a good candidate as it employs a nearly perfect point diffraction spherical wavefront as the reference and takes advantage of the high precision of phase-shifting algorithms as well. Cyclic radial shearing interferometry (C-RSI) successively demonstrate the anti-vibration characteristic and can diagnose transient wavefront with only one single shot by employing a three-mirror common-path configuration and a synchronizing system. Cross-grating lateral shearing interferometer (CG-LSI) is a very compact interferometer that adopts a cross-grating of mm to produce lateral shearing of the diffraction wave of the test wavefront. In this talk, the principles of the above mentioned interferometric wavefront sensing methods would be given in detail and some selected examples based on the research works in our group will be given to illustrate the trends mentioned above.