Temporal integration using the photorefractive square-law converter

A modified real-time holographic technique for obtaining high fidelity integration of coherent or incoherent signals is described. The technique maintains the sensitivity, resolution, and incoherent addressability of a photorefractive incoherent to coherent optical converter and resolves the conflict between uniformity and dynamic range. The response of the resulting optical integrator is characterized in terms of the transfer function, dynamic range, and temporal tunability.