PROBLEM TO BE SOLVED: To enhance the transmission efficiency or reception efficiency of a capacitance transducer.SOLUTION: A capacitance transducer includes one or more elements 2. The element 2 includes a plurality of cell groups 14 having cells 1, each including one electrode, out of a pair of electrodes 4, 5, connected electrically with a common signal extraction electrode 15, and the other electrode provided across a gap 3. In each cell group, the wiring length from each cell to the signal extraction electrode 15 is equal. The capacitance of each cell group, wiring resistance between two adjacent cell groups, the number of cell groups, and the center frequency of the element satisfy a predetermined relation so as to enhance the transmission efficiency or reception efficiency.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】静電容量型トランスデューサの送信効率或いは受信感度を向上する。【解決手段】静電容量型トランスデューサは、素子2を1つ以上備える。素子は、共通の信号取り出し電極15に電気的に接続される、一対の電極4、5のうちの一方の電極と、一方の電極と間隙3を隔てて設けられた他方の電極と、を備えるセル1を有するセル群14を、複数備える。各セル群内では、各セルから信号取り出し電極15までの配線長が等しい。各セル群の静電容量、隣り合う2つのセル群間の配線抵抗、素子内のセル群の数、素子の中心周波数は、送信効率或いは受信感度を向上させるように所定の関係を満たす。【選択図】図1
