Patent ID: 7894046

Claim:
A method for tomographic imaging for estimating flow velocity of a fluid flow sample, comprising: providing a source of at least partially coherent optical radiation through an interferometer; splitting said source in said interferometer into a first optical path for a reference arm and a second optical path for emission onto said fluid flow sample; phase modulating said radiation in said interferometer at a modulation frequency; continuously scanning a fluid flow sample with said source of at least partially coherent optical radiation through said interferometer, said fluid flow sample having a fluid flow therein and a structure in which said fluid flow is defined; detecting backscattered radiation received by said interferometer from said sample to detect interference fringes within said interferometer; demodulating the detected backscattered radiation into inphase and quadrature components corresponding to said interference fringes; processing said inphase and quadrature signals corresponding to said interference fringes established by said backscattered radiation in said interferometer to generate a tomographic structural image; processing said inphase and quadrature signals corresponding to said interference fringes established by said backscattered radiation in said interferometer using an autocorrelation based method to obtain the mean backscattered frequency; processing said backscattered frequencies to generate image showing velocity information; and processing said velocity image and said tomographic structural image to generate a combined image and displaying said combined image.