White balance adjusting device with plural thresholds for range control

摘要

A white balance adjustment device includes an image sensor for converting light of an object into an electrical signal, an amplification circuit for amplifying the electrical signal output from the image sensor, a control voltage limiting circuit for limiting a range of a control voltage to be output to the amplification circuit, and a detection circuit for detecting a quantity of ambient light with a hysteresis characteristic. The limited range of the control voltage is arranged to be variable on the basis of an output of the detection circuit.