Acoustic camera apparatus

Claim 1

An acoustic camera for imaging a target area comprising: A. receiver means for forming a plurality of adjacent receiver beams each for receiving acoustic returns from respective adjacent receiver strips of said target area, said receiver strips being relatively long in the target range direction and relatively narrow in a direction perpendicular thereto; B. transmitter means for insonifying said target area to be viewed and operable to provide a short time pulse of acoustic energy to insonify a strip relatively narrow in said range direction and at least equal to the width of said target area to be viewed; C. said transmitter means being arranged that said insonifying strip sweeps out said target area from a minimum range Rm to a maximum range of interest RM in a predetermined time period, the intersection of said insonifying strip with said receiver strips defining a plurality of elemental areas; D. said receiver means including a plurality of elongated receiver transducers and an acoustic focusing element positioned relative to said plurality of receiver transducers and having at least one spherical surface arranged to focus, from said minimum range Rm out to said maximum range RM, acoustic returns from respective ones of said elemental areas onto respective ones of said receiver transducers; E. said receiver transducers being operable to provide respective output signals in response to impingement of focused acoustic returns; and F. means for processing and displaying said output signals.