Abstract

Resonant holographic interferometry (RHI) provides a method for obtaining species-specific interferograms by recording two simultaneous holograms at two different wavelengths; one tuned near a chemical absorption feature and the other tuned off this feature (typically <0.1-nm separation between lasers).^1-3 Because phase contributions to the interferogram from background species, thermal and pressure gradients, and optical aberrations are subtracted out in the holographic reconstruction process, the resulting interference fringes correspond uniquely to the density of the species under interrogation. The interferogram permits two-dimensional chemical detection that is useful for combustion and plasma diagnostics, medical imaging, and flow visualization. In this work, we evaluate the photorefractive semiconductor ZnTe co-doped with vanadium and manganese (ZnTe:V:Mm) for real-time holographic interferometry at the MR wavelengths of laser diodes. Semiconductor materials can have photorefractive response times of picoseconds so they offer tire potential for ultrahigh-speed data acquisition.⁴

© 1996 Optical Society of America