Noninvasive Vibration Measurement System And Method For Measuring Amplitude Of Vibration Of Tissue In An Object Being Investigated

Abstract

A system and method for measuring the acoustically induced vibrations within a living organism. The object is ensonified to set it into low frequency vibration. A continuous wave beam of ultrasonic energy is transmitted along one path and focused at the tissue to be investigated. A focused transducer receives the reflected beam along a second axis such that the intersection of the transmitted and received beams define a small, concentrated region positioned at the object under investigation. The received beam is phase modulated by the amplitude of vibration of the object producing sidebands whose amplitude can be ratioed to the amplitude of the high frequency peak to determine the absolute amplitude of the low frequency vibration.