Imaging Performance Evaluation Method of Wide-View Underwater Acoustic Lens by Geometrical Skew Ray Analysis

In the image formation performance of an underwater acoustic lens, the use of geometrical skew ray analysis for usually use in optical lens design field was examined. We measured acoustic pressure fields through a single lens, from which the acoustic energy distribution was obtained by using encircled energy. On the other hand, the analyzed acoustic energy distribution was evaluated by geometrical skew ray analysis under the measurement condition including the apodization of the source and effect of water temperature. We compared the measured and analyzed convergence positions, which the diameter of 80% of total amount of acoustic energy is the minimum. Then the both convergence positions correspond. As a result, it was shown that the image performance evaluation of a wide-view acoustic lens by geometrical skew ray analysis is useful. (C) 2010 The Japan Society of Applied Physics