Dynamic fiber specklegram sensing

Angular and Speckle Multiplexing of Photorefractive Holograms by use of Fiber Speckle Patterns

The scheme of using fiber speckle patterns can be applied to the multiplexing of photorefractive holograms. Fiber speckle referencing enhances the angular selectivity of the holograms. Speckle multiplexing is also possible by use of a mode scrambler. Also studied is the feasibility of a hybrid scheme involving simultaneous shift and speckle multiplexing.

Volume hologram scheme using optical fiber for spatial multiplexing

Speckle patterns from optical fibers are used for reference beams in writing and reading volume holograms. The photorefractive volume hologram with the scheme shows good spatial selectivity for spatial (shift) multiplexing. Experimental results are presented and compared with numerical analysis.

Temperature-compensated fiber specklegram strain sensing with an adaptive joint transform correlator

A temperature-compensated fiber specklegram strain sensor with an adaptive joint transform correlator (JTC) is presented. By exploiting the dual-channel correlation of the fiber specklegram JTC, we can measure the temperature-compensated strain. Experimental results have shown that the strain sensitivity can be as high as 0.1 µstrain/1°C.