Self-focusing of acoustical beam in solid by time-reversal processing

We present a study on the selfadaptive focusing of acoustical beam in the solid by time-reversal (TR) method.The theoretical analyses and experiments show that TR can compensate the path difference of sound pulse insolid,and generate the selffocusing of longitudinal and shear wavs at the same time.The experimental values of thefocusing processing gain are agree with the theoretical values.