| 摘要 |
PURPOSE:To always from an ultrasonic image with optimal density by executing feedback control to an amplification degree of an amplifier for amplifying a receiving signal. CONSTITUTION:A receiving signal outputted from an amplifier 10 is sent to an area setting circuit 22 through an A/D converter 20, a receiving signal in a prescribed area is extracted therein, and a histogram is prepared by a histogram circuit 24. A smoothing circuit 26 executes smoothing to the histogram, and a peak retrieval is executed by a peak retrieving circuit 28. A gain value deciding circuit 30 derives a difference amount between the histogram which becomes a reference and the actual histogram, and based on its difference amount, an amplification degree of the amplifier 10 is determined. |
