NOISE FILTERING IN THE INTERFERENCE PATTERN BY DYNAMIC HOLOGRAPHIC RECORDING IN PHOTOREFRACTIVE BI12TIO20 CRYSTALS

The possibilities of stabilization of the interference pattern by filt ration of a random-phase noise caused by vibrations, turbulence, and o ther local changes in the wave front in interferometric measurements a re investigated. Dynamic holographic recording in photorefractive Bi12 TiO20 crystals is used. The parameters of the holographic recording ar e presented for determination of the dynamic range for filtering. Nois e filtering takes place in real time and contributes to the enhancemen t of the contrast and the signal-to-noise ratio of the interference pa ttern. This results in a considerable increase in the sensitivity and the accuracy of the interferometric measurements. (C) 1996 Optical Soc iety of America