An apparatus for determining a ultrasonic speed by means of a v (z) - measurement as well as an ultrasonic microscope with the use of this device

摘要

The ultrasonic sound velocity measuring apparatus or ultrasonic microscope moves the sample to be measured or examined relative to a focusing acoustic probe from its focal point to a defocus point closer to the probe; subjects the intensity of a first reception signal in the peripheral portion of the transducer of the acoustic probe as obtained therefrom in response to said relative movement of the sample, the phase difference between the first reception signal and either the signal for driving the acoustic probe or the corresponding reference signal, the intensity of a second reception signal in the central portion of the transducer of the acoustic probe as obtained therefrom in response to said relative movement of the sample, and the phase difference between the second reception signal, and either the signal for driving the acoustic probe or the corresponding reference signal to more than one sampling at time intervals corresponding to positions in the defocus direction; and obtains data on the intensity and phase difference of the plurality of the first reception signals as obtained by the sampling step as well as data on the intensity and phase difference of the plurality of the second reception signals as obtained by the sampling step as data for vector functions, with respect to the position in the defocus direction, of the wave of interference between the leaky elastic surface wave component and the reflected wave component near the central axis of the acoustic probe so as to calculate the velocity of the leaky elastic surface wave component.