| 摘要 |
PROBLEM TO BE SOLVED: To make a measured picture high in picture quality by measuring a correlated value between adjacent delaying means from a delaying means connected to an oscillation element on one tip side of the outermost side in an oscillation element to a delaying means connected with an oscillation element on the other tip side, thereby correcting the delay amount of the delaying means. SOLUTION: At the time of reading a wave receiving digital signal written in each delaying means, a delay control means decides a delaying means to read first based on a correlated value between a third oscillator 43 near the center of a transmitted/received wave with a second oscillator 42 being the nearest to the center of the transmitted/received wave, namely the reference, and the second oscillator 42 being reference. Next, the delay control means calculates a reading address difference equivalent to a time difference based on a delay time control means and the correlated value to the reading address of a delay line. Then, data required for the focus of a received wave is read out by reading data on each reading address, namely a received wave digital signal, from each delaying means. |
