Along with the development of parallel optical computing, more and more two-dimensional optical modulating and transforming devices with high response speed are needed. As the response times of most of the photorefractive crystals are very short, optically addressed photorefractive BSO spatial light modulators are the most important devices which have been successfully used in many two-dimensional optical information processing systems. However, the response time is still too large for optical computing applications. In order to achieve adequate contrast ratio, a majority of the operation process of the photorefractive spatial light modulators have to account for the accumulating of the photoinduced charges so as to build up a strong internal electric field. The experiment results show that, the photoinduced currents through the external circuits which provide the applied voltage behave with the characteristics of pulses. The properties of the current pulses vary with the wavelength of the write-light, the direction of the external field, the value of the applied voltage, the thickness of the BSO films and the properties of the external circuits. The analysis of the photoinduced current pulses is useful for optimizing the structure, the operation modes and the performance of the photorefractive spatial light modulators. Furthermore, the analysis can provide some useful information for choosing appropriate materials and devices for optical computing applications, and building up efficient all-optical architecture for the future parallel optical computers.

Date Published: 12 March 2008
PDF: 11 pages
Proc. SPIE 6624, International Symposium on Photoelectronic Detection and Imaging 2007: Optoelectronic System Design, Manufacturing, and Testing, 66241R (12 March 2008); doi: 10.1117/12.791185

Published in SPIE Proceedings Vol. 6624:
International Symposium on Photoelectronic Detection and Imaging 2007: Optoelectronic System Design, Manufacturing, and Testing
Liwei Zhou, Editor(s)