PHASE-CONJUGATE HOLOGRAPHIC SYSTEM FOR HIGH-RESOLUTION PARTICLE-IMAGEVELOCIMETRY

A novel holographic particle-image velocimeter system has been develop ed for the study of three-dimensional (3-D) fluid velocity fields. The recording system produces 3-D particle images with a resolution, a si gnal-to-noise ratio, an accuracy, and derived velocity fields that are comparable to high-quality two-dimensional photographic particle-imag e velocimetry (PIV). The high image resolution is accomplished through the use of low f-number optics, a fringe-stabilized processing chemis try, and a phase conjugate play-back geometry that compensates for abe rrations in the imaging system. In addition, the system employs a refe rence multiplexed, off-axis geometry for the determination of velocity directions with the cross-correlation technique, and a stereo camera geometry for the determination of the three velocity components. The c ombination of the imaging and reconstruction subsystems makes the anal ysis of volumetric PIV domains feasible.