Abstract

A multi directional holographic grating was performed to validate self-referenced digital holographic interferometry. The manufacturing of diffraction grating is particular because the reference beam interferes by reflection with four object beams that have specific orientations (kite configuration) to not generate diffraction orders that overlap in 2D Fourier plane. Two optical setups are provided for analyzing the variations in refractive index of a compressible flow (small supersonic jet at different injection pressures). The sequential selection of four diffraction orders allows to reconstruct the field of gradient phase along specific directions. The integration of the derivative fields yields obtaining the absolute phase field. The results, compared with those obtained by digital holography using a separated reference, validate self-referenced digital holography method.

© 2015 Optical Society of America