Imaging of ultrasonic-surface motion by optical multiplexing

摘要

The invention relates to method and apparatus for optically detecting transient motion from a scattering surface. A broad laser beam is directed on to an area of the scattering surface of an object to be imaged to thereby scatter the laser beam and produce a plurality of modulated signals. A demodulator simultaneously demodulates the modulated signals to provide a plurality of demodulated signals to an array or matrix of detectors. The detector array simultaneously converts the demodulated light signals into electrical signals representative of the transient motion. The optical detection technique according to the invention is particularly useful for detecting small deformations produced by ultrasound, in a timely manner by parallel processing information provided by a matrix of detectors.