| 摘要 |
PURPOSE:To eliminate an influence of a right-over disturbing sound wave by obtaining from a secondary pressure slanting type converter a reference signal needed to determine the sound receiving azimuth of a pressure-slanting type converter. CONSTITUTION:Polymer piezoelectric material 1 is wound in a cylindrical shape and around the cylinder, coupled diaphragms 4a-4d are fitted in four directions at right angles while the center of piezoelectric material 1 between diaphragms is fixed by fixing members 6a-6d, and 7. On arrival of an external sound wave at the converter mentioned above, a difference in sound pressure is made between both surfaces of a diaphragm, which causes the diaphragm to vibrate. This vibration propagates piezoelectric material 1 and is converted into an electric signal, which is les out by way of electrodes 2a-2d, and 3a-3d. Then, a sum of signals of opposing diaphragms and their difference are extracted to measure a desired azimuth from both signals. In this way, an influence of a right-over disturbing sound wave can be eliminated. |
