Provided is an ultrasonic diagnosis system in which an ultrasonic diagnosis device is configured from a front-end (FE) device and a back-end (BE) device. The BE device is provided with two sensor pairs. Each sensor pair is configured from a light sensor and an object detection sensor. A control unit sets a backlight level adaptively on the basis of a light detection value when no object is detected. When an object is detected by either of the object sensors, the light detection value from the light detection sensor adjacent to said object is discarded.
