| 摘要 |
PURPOSE:To obtain a two-way directivity by arranging two delay circuit groups for ultrasonic wave detecting elements arranged in a 1-D or 2-D array to decrease the delay time in the order of arrangement in one group while increasing it in the other. CONSTITUTION:Wave fronts 47 and 48 reflected from different objects by ultrasonic beams emitted in different two directions within a determined cycle are detected with ultrasonic wave detecting elements 40a-40d arranged in a 1-D array. The outputs of the elements 40a-40d are inputted into delay circuits 43a-43d composing the first delay circuit group and delay circuits 44a-44d composing the second delay circuit group separately. The delay time of the circuits 43a-43d and 44a-44d is set to decrease from the circuit 43a to the circuit 43d gradually while increasing from the circuit 44a to the circuit 44d so that the wave fronts 47 and 48 can be detected simultaneously. The circuits 43a-43d and the circuits 44a-44d are added up by groups and connected to output terminals 45 and 46 separately. |
