Optical Logarithmic Transformation of Speckle Images with Bacteriorhodopsin Films

摘要

The application of logarithmic transformations to speckle images is sometimes desirable in coverting the speckle noise distribution into an additive, constant-variance noise distribution. The optical transmission properties of some bacteriorhodopsin films are well suited to implement such a transformation optically in a parallel fashion. I present experimental results of the optical conversion of a speckle image into a transformed image with signal-independent noise statistics, using the real-time photochromic properties of bacteriorhodopsin. The original and transformed noise statistics are confirmed by histogram analysis.