Patent attributes
Each of an excitation element for exciting surface acoustic waves in two directions and a receiving element for receiving surface acoustic waves from two directions is constructed by forming a comb-like electrode on the front surface of a piezoelectric body in the form of a thin film and a plate electrode on the rear surface thereof. The comb-like electrode on the front surface has one line of bus electrode, and a plurality of electrode fingers which are extended from the bus electrode and bent in V-shape in the middle. The voltage in the excitation element and in the receiving element is controlled by providing a terminal resistance for preventing reflection of an applied AC voltage at the terminal end, between the terminal end portion of the comb-like electrode and the plate electrode, or adjusting the resistance value of the bus electrode and/or the plate electrode, or adjusting the capacitance value between the electrode finger and the plate electrode.
