COMMENT: ACOUSTICAL HOLOGRAPHY
Acoustical Holography has developed into a subject in its own right and separate conferences on this subject ar now held. The fourth such meeting will take place in Santa Barbara on April 10-12, 1972. ( This meeting will be immediately followed by a SPIE seminar-in-depth on non-destructive testing that will be held in conjunction with this Fourth International Symposium on Acoustical Holography.) In this column the proceedings of the first three meetings are reviewed to provide a background to the fourth symposium.