Endoscope light source device, endoscope apparatus, operating method of endoscope light source device, and light amount adjusting method

An endoscope light source device comprising:

• a light source device including first to fifth light sources configured to emit first to fifth light having wavelengths different from one another, and generating illumination light to be emitted to an object;
• and
• a light source controller configured to adjust light amounts of the respective first to fifth light based on a light amount ratio setting value to be used for setting a first light amount ratio relating to color balance, and a second light amount ratio and a third light amount ratio relating to color representation,
• the first light and the second light being narrow band light in a blue region,
• the third light being in a green region,
• the fourth light and the fifth light being narrow band light in a red region,
• the first light amount ratio being a ratio of a sum of the light amounts of the first light and the second light, the light amount of the third light, and a sum of the light amounts of the fourth light and the fifth light,
• the second light amount ratio being a light amount ratio of the first light and the second light,
• the third light amount ratio being a light amount ratio of the fourth light and the fifth light,
• the light source controller
• adjusting the light amount ratio of the first light and the second light to achieve the second light amount ratio based on the light amount ratio setting value so as to adjust the color representation from a yellow region to a red region in an image of the object, and
• adjusting the light amount ratio of the fourth light and the fifth light to achieve the third light amount ratio based on the light amount ratio setting value so as to adjust the color representation in the red region in the image.

A light amount adjusting method for adjusting light amounts of a first light source and a second light source configured to emit first light and second light of narrow band light in a blue region, a third light source configured to emit third light of the narrow band light in a green region, a fourth light source and a fifth light source configured to emit fourth light and fifth light of the narrow band light in a red region, the method being performed by a light source controller and comprising:

• adjusting a ratio of a sum of the light amounts of the first light and the second light, the light amount of the third light, and a sum of the light amounts of the fourth light and the fifth light to achieve a first light amount ratio based on a light amount ratio setting value so as to adjust color balance;
• adjusting a light amount ratio of the first light and the second light to achieve a second light amount ratio based on the light amount ratio setting value so as to adjust color representation from a yellow region to a red region in an image of an object;
• and
• adjusting a light amount ratio of the fourth light and the fifth light to achieve a third tight amount ratio based on the light amount ratio setting value so as to adjust the color representation in the red region in the image.