| 摘要 |
PROBLEM TO BE SOLVED: To improve SN ratio by adding a signal in which the positive part of a corrected signal obtained by adding a delay digital signal after the lapse of a minute time to a positive-negative reversed received digital signal is eliminated to the received signal to provide a corrected digital signal. SOLUTION: The analog signal 2s from a probe 2 is converted into a digital signal 5s and held as received digital signals 6s, 7s in memories 6, 7, and a delay digital signal 8s converted and outputted after the lapse of 1/1000 second from the digital signal 5s is held in a memory 8. In a superposing circuit 10, the delay digital signal 8s is added to a reverse digital signal 9s in which the positive and negative of the received digital signal 7s of the memory 7 are reversed to output a corrected signal 10s. In a superposing circuit 12, a negative corrected signal 11s in which the positive part of the correction signal 10s is eliminated is added to the received digital signal 6s of the memory 6 to output a corrected digital signal 12s. In a D/A converter 13, a corrected analog signal 13s in which the corrected digital signal 12s is converted is outputted to the display part 3 of an ultrasonic flaw detector. |
