Dynamic Fizeau interferometer based on the lateral displacements of the point sources

- A novel dynamic Fizeau interferometer based on the lateral displacements of the point sources.
- The interferometer is immune to retrace error and poor contrast.
- The technology can be extended to large aperture Fizeau interferometers.
- The dynamic interferometry can be applied to interferometers such as Twyman-Green and Mach-Zender interferometers.

A novel dynamic Fizeau interferometer (DFI) is proposed based on simultaneous phase shifting with different incident angles through the lateral displacements of the point sources. Four point sources with identical intensity are generated using a phase grating and the corresponding interferograms with equal phase step are introduced by properly adjusting each point source to the optical axis of the interferometer. The interferograms are separated and clearly imaged at the CCD target in a single shot by putting a lens array in the imaging system, thereby realizing dynamic interferometry. The experimental results show the feasibility and high precision of the DFI.