Patent ID: 7369250
Filing Date: 2008-05-06
Classification: G01H,G01N

Abstract:
1. A method to generate and detect ultrasonic surface displacements at a remote target comprising: generating an ultrasonic wave at a first location on an upper surface of the remote target with a generation laser beam directed at the first location, wherein the generation laser beam forms a generation field on the remote target; reflecting the ultrasonic wave from an interior surface of the remote target, wherein the reflected ultrasonic wave produces ultrasonic displacements at a second location on the upper surface of the remote target; generating a detection laser beam; directing the detection laser beam at the upper surface of the remote target wherein the detection laser beam forms a detection field on the target and wherein the detection field overlaps the generation field and the second location; scattering the detection laser beam with the ultrasonic displacements at the second location on the upper surface of the remote target to produce phase-modulated light; collecting the phase-modulated light; processing the phase-modulated light to: obtain data representative of the ultrasonic surface displacements at the surface; and inspection information representative of the interior of the remote target, and visually presenting at least a portion of the data.