Holographic velocimetry with object conjugate reconstruction (OCR): simultaneous velocity mapping in fluid and solid mechanics

Abstract

This paper reports a significant step forward in holographic velocimetry, which provides simultaneous displacement measurements in fluid and solid mechanics. Known as object conjugate reconstruction (OCR), this new approach unifies the disciplines of holographic velocimetry and holographic interferometry and provides a single measurement technique for the study of surface–flow interactions throughout a volume. Using complex–correlation processing, it enables sub–wavelength displacement resolution for all three components of a velocity field and a dynamic range exceeding 100:1. Prior to OCR, and the use of complex-correlation processing, measurement of surface-flow interactions required multiple techniques applied in a hybrid fashion, which had precluded widespread use.