PROBLEM TO BE SOLVED: To provide a power source circuit in which increase in the scale of a power source circuit for an ultrasonic wave image display device is suppressed, allowing transmission of ultrasonic wave that requires a large current.SOLUTION: A power source circuit 1 of a transmission circuit that transmits a drive pulse to a vibrator which generates ultrasonic wave includes: a variable voltage power source 2 a first power source line which connects an output terminal of the variable voltage power source 2 to a power source terminal of a transmission circuit 102 through an energy accumulation circuit containing capacitors 4, 8 and constant current circuits 3, 7 a second power source line which directly connects the output terminal of the variable voltage power source 2 to the power source terminal of the transmission circuit 102 and a control part 11 which, based on a transmission condition of ultrasonic wave, performs switching control between a first mode for supplying power to the transmission circuit 102 by using the first power source line and a second mode for supplying power to the transmission circuit 102 by using the second power source line.
