Ultrasonic diagnostic apparatus

Abstract

An ultrasonic diagnostic apparatus comprises an ultrasonic transducer for transmitting and receiving ultrasonic waves to and from a body to be examined and a control section for automatically determining the optimum image conditions on the basis of the echo signals obtained by the ultrasonic transducer. The control section comprises circuits for controlling the amplification factor of the echo signals, the amplification factors of the echo signals for the respective visual field depths and the adjustment of image contrast, on the basis of the echo signals obtained by the ultrasonic transducer. These control circuits comprises a histogram forming circuit for forming histogram information on the basis of the echo signals obtained by ultrasonic transducer, which represents a histogram in which the brightness values of the image to be displayed as gradations and the number of pixels of the respective corresponding brightness values as frequencies; a compared value detecting circuit for detecting a median value or a peak value of the formed histogram on the basis of the histogram information; and an amplification factor determining circuit for comparing the compared value with a predetermined reference value and for determining the amplification factor of the echo signals or the adjustment level of the image contrast so as to eliminate the difference between the compared value and the reference value. The ultrasonic diagnostic apparatus can automatically determine the optimum image conditions at all times, irrespective of the thickness of the layer of fat or the state of the tissue of the body to be examined.