Share Email Print

Optical Engineering

All-optical nonlinear holographic correlation using bacteriorhodopsin films
Author(s): Ralph Thoma; Michael Dratz; Norbert A. Hampp
Format Member Price Non-Member Price
PDF $20.00 $25.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Films made of the halobacterial photochrome bacteriorhodopsin (BR) can be used in a number of holographic real-time applications. Their application as active material in a dual-axis joint-Fourier-transform (DAJFT) real-time correlator was shown recently. The BR films have a strong nonlinear intensity dependence on the light-induced absorption and refractive-index changes. Therefore the holographic diffraction efficiency also shows a nonlinear dependence on the writing intensity. We investigate the effect of this nonlinearity on the result of the correlation process in a bacteriorhodopsin-based DAJFT correlator. Numerical models supporting the experimental observations are presented. It was found that the BR film combines the holographic function for most objects with that of a spatial bandpass filter, whose center frequency is tuned by the writing intensity. This results in smaller peak widths and a suppression of the sidelobes. BR films allow the application of this nonlinear behavior in real time to the all-optical correlation process.

Paper Details

Date Published: 1 May 1995
PDF: 7 pages
Opt. Eng. 34(5) doi: 10.1117/12.201654
Published in: Optical Engineering Volume 34, Issue 5
Show Author Affiliations
Ralph Thoma, AGFA-Gevaert AG. (Germany)
Michael Dratz, Univ. of Munich (Germany)
Norbert A. Hampp, Univ. Muenchen (Germany)

© SPIE. Terms of Use
Back to Top