Photorefractive novelty filters for transient phase evaluation

In our report we compare different ways of realizing an optical novelty filter with photorefractive barium titanate crystals. We present experiments on the basis of beam fanning, two-wave mixing and self-pumped phase conjugate geometries. The application of photorefractive novelty filters not only for phase visualization but also for the measurement of transient phase changes in a laser beam is demonstrated. The phase calculation from an interferogram is supplied or replaced by the novelty filter's phase transfer function. The use of such techniques instead of conventional interferometry for transient phase evaluation results in a simplified measuring procedure.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.