摘要:
A transmitting, focusing, ultrasonic wave transducer (20) is excited by high-frequency pulses sent from a high-frequency pulse generator (1); the leakage elastic surface waves are excited in a sample (6) by the focusing ultrasonic wave beams of the transducer (20); the waves emitted again are received by a receiving focusing ultrasonic wave transducer (24); the received signals are sent to a mixer (23) where a difference in phase is detected relative to reference signals produced from a high-frequency oscillator (18) in the high-frequency pulse generator (1); and the detected output is supplied as a display signal to a display (9 or 14). The transducers (20, 24) and the sample (6) are relatively moved by a moving device (7 or 10) two-dimensionally on a plane parallel to the surface of the sample or at right angles to the surface of the sample. In synchronism with this movement, the surface of the display (9 or 14) is swept to obtain an ultrasonic microscopic image or a V(z) curve on the display surface.
摘要:
The ultrasonic sound velocity measuring apparatus or ultrasonic microscope of the present invention which rely on the V(z) characteristics are characterized by the following:
the sample (11) to be measured or examined is moved relative to a focusing acoustic probe (8) from its focal point to a defocus point closer to the probe (8); the intensity of a first reception signal in the peripheral portion (8a) of the transducer (8a, 8b) of the acoustic probe (8) as obtained therefrom in response to said relative movement of the sample (11), the phase difference between the first reception signal and either the signal for driving the acoustic probe (8) or the corresponding reference signal, the intensity of a second reception signal in the central portion (8a) of the transducer (8a, 8b) of the acoustic probe (8) as obtained therefrom in response to said relative movement of the sample (11), and the phase difference between the second reception signal and either the signal for driving the acoustic probe (8) or the corresponding reference signal are subjected to more than one sampling at time intervals corresponding to positions in the defocus direction; 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 obtaied by the sampling step are obtained 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 (8) so as to calculate the velocity of the leaky elastic surface wave component.
摘要:
@ A transmitting, focusing, ultrasonic wave transducer (20) is excited by high-frequency pulses sent from a high-frequency pulse generator (1); the leakage elastic surface waves are excited in a sample (6) by the focusing ultrasonic wave beams of the transducer (20); the waves emitted again are received by a receiving focusing ultrasonic wave transducer (24); the received signals are sent to a mixer (23) where a difference in phase is detected relative to reference signals produced from a high-frequency oscillator (18) in the high-frequency pulse generator (1); and the detected output is supplied as a display signal to a display (9 or 14). The transducers (20, 24) and the sample (6) are relatively moved by a moving device (7 or 10) two-dimensionally on a plane parallel to the surface of the sample or at right angles to the surface of the sample. In synchronism with this movement, the surface of the display (9 or 14) is swept to obtain an ultrasonic microscopic image or a V(z) curve on the display surface.
摘要:
An ultrasonic transmitter-receiver (16) for radiating a focused ultrasonic beam (39) and a sample (23) are moved relative to each other in the axial direction of the ultrasonic beam. A reflected wave from the sample (23) is received and a curve V(Z) of variations in the level of the reflected wave with respect to the relative movement is obtained. A reference level of interference of a directly reflected wave and a leaky elastic wave is substracted from V(Z) to perform waveform processing. The waveform processing output is subjected to a waveform analysis, and from the analysis results, the velocity and/or the attenuation of the leaky elastic wave are calculated.
摘要:
The ultrasonic sound velocity measuring apparatus or ultrasonic microscope of the present invention which rely on the V(z) characteristics are characterized by the following: the sample (11) to be measured or examined is moved relative to a focusing acoustic probe (8) from its focal point to a defocus point closer to the probe (8); the intensity of a first reception signal in the peripheral portion (8a) of the transducer (8a, 8b) of the acoustic probe (8) as obtained therefrom in response to said relative movement of the sample (11), the phase difference between the first reception signal and either the signal for driving the acoustic probe (8) or the corresponding reference signal, the intensity of a second reception signal in the central portion (8a) of the transducer (8a, 8b) of the acoustic probe (8) as obtained therefrom in response to said relative movement of the sample (11), and the phase difference between the second reception signal and either the signal for driving the acoustic probe (8) or the corresponding reference signal are subjected to more than one sampling at time intervals corresponding to positions in the defocus direction; 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 obtaied by the sampling step are obtained 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 (8) so as to calculate the velocity of the leaky elastic surface wave component.
摘要:
An ultrasonic transmitter-receiver (16) for radiating a focused ultrasonic beam (39) and a sample (23) are moved relative to each other in the axial direction of the ultrasonic beam. A reflected wave from the sample (23) is received and a curve V(Z) of variations in the level of the reflected wave with respect to the relative movement is obtained. A reference level of interference of a directly reflected wave and a leaky elastic wave is substracted from V(Z) to perform waveform processing. The waveform processing output is subjected to a waveform analysis, and from the analysis results, the velocity and/or the attenuation of the leaky elastic wave are calculated.