Patent ID: 7898577

Claim:
A light source device comprising: a first light-emitting section which generates illumination light to be applied to a subject, a second light-emitting section which generates illumination light with wavelength different from the illumination light generated from the first light-emitting section, and an integrated output value control section which independently controls integrated output values of the first light-emitting section and second light-emitting section in synchronism with image pickup timing at which the subject is photographed, wherein the integrated output value control section includes a comparator which compares a dimming signal generated based on an image pickup signal from an image pickup element which photographs the subject with a reference level, an integrated output value control circuit which controls the integrated output values of the first and second light-emitting sections based on the comparison result, and a light-emitting section selecting section which selects a light-emitting section supplied with an output signal of the integrated output value control circuit from the first and second light-emitting sections, wherein the integrated output values contain light emission intensities and light emission periods of the first and second light-emitting sections, the light emission periods of the first and second light-emitting sections are synchronized with an exposure period of the image pickup element and at least one of the light emission intensities and light emission periods of the first and second light-emitting sections are independently controlled within the exposure period, and wherein the integrated output value control section compares the light emission period with the exposure period of the image pickup element when it is detected in a comparison by a comparator that the reference level is larger than the dimming signal and controls at least one of the light emission intensities and light emission periods of the first and second light-emitting sections based on the comparison result obtained at this time.