Shift-invariant real-time edge-enhanced VanderLugt correlator using video-rate compatible photorefractive polymer.
We demonstrated a real-time shift-invariant VanderLugt correlator (VLC). The VLC was implemented with a 37 microm thick bis-triarylamine side-chain polymer matrix photorefractive (PR) polymer composite operating at 532 nm wavelength. Correlation selectivity was enhanced by real-time edge enhancement. The advantage of the VLC is that its architecture allows overcoming the PR material response speed. A correlator of this type enables a fast shift-invariant search of a large optical image database. A high degree of shift invariance in our correlator was possible because of the material thickness. The angular bandwidth of this material was measured experimentally in a degenerate four-wave mixing setup, and it was found to be in a very good agreement with the theory.
Heifetz
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A
Department of Electrical and Computer Engineering, Northwestern University, Evanston, Illinois 60208, USA. heifetz@ece.northwestern.edu
Pati
G S
GS
Shen
J T
JT
Lee
J-K
JK
Shahriar
M S
MS
Phan
C
C
Yamamoto
M
M