| 摘要 |
PURPOSE:To accurately measure a sound velocity in a fine area on the surface of a sample by propagating a reflected wave in the vicinity of the center of the concave surface of a lens which transmits and receives an ultrasonic wave signal on the surface of the sample and transmitting/receiving ultrasonic waves which reach the lens individually. CONSTITUTION:This probe is provided with a transmission/reception part 14b which transmits/ receives the ultrasonic wave in the vicinity of the center of the concave surface 11a and a 2nd transmission/reception part 14a which transmits an ultrasonic wave to the sample 15 and also receives the ultrasonic wave propagated in the surface part of the sample 15 and reaching the edge part of the concave surface 11a. Consequently, the ultrasonic wave 16 which is sent by the reception part 14b is reflected by the surface of the sample 15 and received as an echo by the transmission/reception part 14b again. Further, the ultrasonic wave 17 which is transmitted by the transmission/reception part 14a is made incident partially on the sample 15 at the Rayleigh critical angle and propagated as a surface wave on the surface and the wave is projected at the Rayleigh critical angle similarly and received as the echo 19 by the transmission/reception part 14a again. The other part of the ultrasonic wave 17 is reflected by the surface of the sample 15 and propagated as an echo 18 toward the ultrasonic probe, but no transmission/reception parts 14a and 14b is present on its reception part and the wave is not received. |
