ULTRASONIC CABLE TRANSMITTER*RECEIVER

摘要

PURPOSE:To obtain the good directional characteristics by removing the upper electrode from the opposing end face by the amount of the length nearly identical to the length from the end face where the upper electrode of the piezoelectric plate is applied to the end close to the lower electrode and then providing the parasitic parts symmetrically at the both ends. CONSTITUTION:Rectangular piezoelectric plate 11 is provided, along with upper electrode 13 which is installed in the depth direction of plate 11 and covering even one end face of plate 11 provided on the face where the ultrasonic wave is transmitted and received, plus lower electrode 15 installed on the other face of plate 11 and apart from electrode 13. And electrode 13 provided on face 12a of plate 11 is set to length l3 which is nearly identical to the sum of length l1 from end face 14b and length l2 of gap 16 formed between electrodes 13a and 15. In such way, the parasitic parts are secured symmetrically at the both ends to obtain the good directional characteristics.