Patent ID: 9651477
Date: 2017-05-16
CPC Classifications: G01H,G01N,G01P

Claim:
1. A heterodyne speckle imaging sensor system, comprising: a laser source emitting a linearly polarized laser; a first beam splitter to divide the linearly polarized laser from the laser source into a probe beam along a probe path and a reference beam along a reference path; a bi-convex probe lens in the probe path to provide focus adjustment for the probe beam; a first mirror in the probe path to reflect the probe beam as a redirected probe beam; a scattering source having a diffuse surface to scatter the redirected probe beam as a scattered radiation; bi-convex collecting lens to collect a portion of the scattered radiation as a collected radiation; a second mirror for redirecting the collected radiation as a propagated beam; plano-convex defocusing lens to defocus a field of the propagated beam; a third mirror to redirect the resulting defocused propagated beam; a polarizing filter to absorb horizontally polarized components of said propagating beam as a probe electric field towards an image plane; an arrangement of acousto-optic modulators to effect frequency offset of the electromagnetic field associated with the reference beam to result in a frequency offset reference beam; a reference mirror to redirect said frequency offset reference beam; a plano-convex reference lens to focus said redirected frequency offset reference beam as a focused reference beam; a reference spatial filter to spatial filter said focused reference beam to result in a diverging beam; a plano-convex collimating lens to collimate said diverging beam as a collimated reference beam; another polarizing filter to absorb horizontally polarized components of said collimated reference beam as a reference electric field towards said image plane; a second beam splitter to additively combine the probe and reference electric fields towards said image plane; and a focal plane array disposed along said image plane, wherein said probe and reference electric fields as additively combined are sensed by said focal plane array for detection of changes in the random scattered radiation.