Light source device, endoscope system, and control method

A light source device for generating illumination light to be emitted toward an observation object, the light source device comprising:

• a first light source configured to emit light having a peak wavelength in a first wavelength region as part of the illumination light;
• a second light source configured to emit light having a peak wavelength in a second wavelength region as part of the illumination light;
• and
• a processor comprising hardware, wherein the processor is configured to:
• acquire spectrum setting information from a memory;
• and
• control, based on the spectrum setting information, an emitted light amount of the first light source and an emitted light amount of the second light source so that the emitted light amount of the first light source becomes larger than the emitted light amount of the second light source,
• wherein:
• the observation object includes a region of interest, a merkmal, and a peripheral portion;
• the merkmal represents a component being present in an area outside of the region of interest, the area being correlated to an area in which the region of interest is present;
• the peripheral portion represents outside of the region of interest, and excludes the merkmal;
• the spectrum setting information is set based on a merkmal observed ratio that is preset;
• the merkmal observed ratio is a ratio between a spectral reflectance in the merkmal and a spectral reflectance in the peripheral portion in each of a plurality of wavelength regions divided from a visible light wavelength region;
• and
• a degree of disassociation of the merkmal observed ratio in the first wavelength region from 1 is greater than a degree of disassociation of the merkmal observed ratio in the second wavelength region from 1, and
• wherein, when a ratio between a spectral reflectance in the region of interest included in the observation object and the spectral reflectance in the peripheral portion in each of the plurality of wavelength regions is regarded as a region-of-interest observed ratio that is preset, in the first wavelength region, the degree of disassociation of the merkmal observed ratio from 1 is greater than a degree of disassociation of the region-of-interest observed ratio from 1.