We have experimentally demonstrated a single-beam interferometer that effectively subtracts an exponentially weighted history of the input from the current value, thus functioning as a novelty filter. The single-beam interferometer uses signal depletion due to noise amplification (fanout) in a specially cut crystal of photorefractive BaTiO3. To demonstrate its real-time operation we used a Hughes liquid-crystal light valve to convert a video image into a phase- and/or amplitude-modulated input signal. Potential applications of this interferometer include image-clutter removal, motion detection and tracking, edge enhancement, and image time differentiation.
© 1988 Optical Society of America
Original Manuscript: May 6, 1988
Manuscript Accepted: June 27, 1988
Published: October 1, 1988
Joseph E. Ford, Yeshaiahu Fainman, and Sing H. Lee, "Time-integrating interferometry using photorefractive fanout," Opt. Lett. 13, 856-858 (1988)