| 摘要 |
PURPOSE:To obtain a signal equivalent to a transmitted signal obtained by a transmitting constitution by a reflecting constitution using only a single probe system by using a material such as glass or metal having large acoustic impedance. CONSTITUTION:In the upper surface l1 and lower surface l2 of a certain biological sample 100 having a thickness (d), a sample board 110 consisting of a material such as glass or metal having large acoustic impedance is backed on the lower surface l2. A part of ultrasonic beams 120 incident from the upper part of the sample is reflected by the border face l1 and a large part of the beams is transmitted into the sample 100. The waves transmitted through the sample 100 are reflected by the border face l2, transmitted again upwards through the sample 100, projected from the sample 100 into water 130 through the border face l1 and then detected by the probe system 140 as reflected sound waves. Reflection on the border face l2 is almost complete reflection, the reflected signal is extremely high and the reflected wave on the border face l1 is remarkably low, so that the reflected signal is determined by the reflected sound wave from the border face l2 and the reflected signal receives disturbance similar to twice transmission through the sample. |
