The results immediately suggest several potential applications. One is the detection of underwater mines, some of which can be rigged to detonate on receiving a sonar signal. An acoustic-daylight system might be able to locate these devices without triggering them. Imaging with ambient noise could provide vision for autonomous underwater vehicles, enabling them to steer around obstacles without help from a human operator on a surface ship and to monitor the structural integrity of oil rigs and other large maritime platforms. Conceivably, we can take acoustic-daylight imaging further, for it is still a nascent concept.
Prelirninary analysis indicates that the barrels can be seen even when they are on the seafloor.
In the months ahead, we plan to replace the spherical reflector with a phased array containing as many as 1,000 hydrophones. At the same time, we shall be developing dedicated algorithms to provide image enhancement and automatic image recognition. Calif. Buckingham is professor of ocean acoustics there and holds a visiting professorship at the University of Southampton in England. He received his Ph.D. in physics from the University of Reading and has written and edited numerous articles and books on acoustics. An itinerant yachtsman, Potter sailed across the Pacific Ocean last fall to direct the Acoustic Research Laboratory of the National University of Singapore.