We present a joint Fourier-transform correlator working at a 10-kHz repetition rate. It is based on a photorefractive Sn2P2S6 crystal operated in the pulsed direct band-to-band photoexcitation regime at a wavelength of 532 nm and a pulse length of 50 ns. The intersection of two plane waves with a total pulse fluence of 100μJ/cm2 results in a buildup of thin dynamic holograms to a typical diffraction efficiency of 10-4 in a time of ~1μs and decay again in less than 10μs . The correlator was tested by a fast image sequence generated by the pulsed readout of a holographic memory system. Successful correlation at a rate of 10 kHz has already been achieved for a pulse energy of only 200 nJ in the template images.
© 2001 Optical Society of America
(100.1160) Image processing : Analog optical image processing
(100.4550) Image processing : Correlators
(160.5320) Materials : Photorefractive materials
(190.5330) Nonlinear optics : Photorefractive optics
(200.4560) Optics in computing : Optical data processing
R. Ryf, G. Montemezzani, P. Günter, A. A. Grabar, I. M. Stoika, and Yu. M. Vysochanskii, "High-frame-rate joint Fourier-transform correlator based on Sn2P2S6 crystal," Opt. Lett. 26, 1666-1668 (2001)