Acoustic force generator for detection, imaging and information transmission using the beat signal of multiple intersecting sonic beams

摘要

A force is produced within an object by two intersecting ultrasonic beams. The frequency of this force is equal to the beat frequency of the two intersecting beams when their frequencies are made different, or the force may vary as a function of a baseband audio signal f(t) that is used to modulate one of the two beams. The sonic waves produced at the intersection of the two beams can be used to detect the presence of objects or to image objects based on their mechanical properties, or to regenerate desired audio signals at the intersection.