| 摘要 |
PURPOSE:To provide an ultrasonic probe with which it is prevented that the reflected wave from a test specimen is overlaid with the reverberation due to the inner face reflection of an acoustic lens and that the reflected wave from the test specimen can not be distinguished. CONSTITUTION:The lens length L of an acoustic lens is set so as to make the period (2A/CL+2/CM) from the time the ultrasonic wave radiated from a piezoelectric element 3 is reflected by a test specimen to the time the ultrasonic wave is detected by the piezoelectric element 3 as a specimen echo be a middle of the time (2A/CL) of primary inner echo Ei of the acoustic lens 22 and the time (2X2A/CL) of the secondary inner echo, wherein the f stands for the focusing distance of the acoustic lens 22, D for the opened diameter, 6 for the open angle, CL for the acoustic velocity in the acoustic lens, and CM for the acoustic velocity in the transmission medium. Even if an ultrasonic probe 21 is moved closer to the test specimen, the echo Es of the test specimen is surely prevented from being overlapped the inner echo Ei, 2Ei. |
