Temporal Fourier-Transform Phase Retrieval in Photorefractive Optical Transient Detection

A photorefractive optical transient detection (OTD) system is a kind of adaptive interferometer for detection of temporal changes of a signal while suppressing static background. Therefore, OTD allows measurement of intensity and phase with improved contrast. Most systems are based on two-wave mixing in photorefractive materials. A photorefractive transient detection microscope, an OTD system for imaging (also known as TDI and novelty filter), was demonstrated by Cudney et al. [1], and varieties of systems have been developed for both imaging [2] and single-spot detection [3]. However, previous works rely on conventional intensity measurements, where partial information about input signal phase changes are obtained by calibration. Recently, we managed to implement an off-axis interferometric technique to recover and analyze the complex-field on a TDI system [4].