| 摘要 |
PURPOSE:To achieve a highly accurate adjustment of focus by bringing the second maximal value to its maximum through a control sequentially detecting three maximal values in the intensity of reflected ultrasonic waves with the relative displacement of an ultrasonic condenser lens for projecting ultrasonic waves in such a direction as to approach a sample. CONSTITUTION:A driver 12 is provided to detect the position of an acoustic lens 4 with respect to a sample 8 while intermittently displacing it in the direction Z and controlled by a driving signal of an arithmetic controller 13 through an interface control circuit 14 and a position controller 15. A high frequency generation 1 is controlled by a device 14 and emits ultrasonic waves once fed to a transducer 3 through a circulator 2. A memory device 13 is connected to the device 14. A reflected wave detection signal of a signal processing circuit 9 is fed to the device 13 following an AD conversion 17, while displayed on a CRT 11 synchronizing a scan controller 6. The lens 4 is driven to approach the sample 8 and the driver 12 is driven to such a position as to bring the second maximal value among three maximal values being detected sequentially with the circuit 9. |
