主权项 |
1. An endoscope light source unit, comprising:
a first light source section emitting a first illumination light composed of white light; a second light source section emitting a second illumination light composed of a narrow-band light in a wavelength band narrower than that of the first illumination light, orthogonally to a direction in which the first illumination light travels; a light combining member positioned at an intersection of the first and second illumination lights in such a manner that it is tilted at an angle of 30° to 60° to the direction in which the first illumination light travels, which member has a reflection section located in its center for reflecting at least the second illumination light, and a transmission section surrounding the reflection section for transmitting the first illumination light, the light combining member transmitting the first illumination light through the transmission section and, at the same time, reflecting the second illumination light by means of the reflection section to form a combined light of the first and second illumination lights so that a beam of the second illumination light may be located in a central part of a beam of the first illumination light, wherein the reflection section of the light combining member is approximately elliptical in shape and has a length of at least one of a major or minor axis which is 10 to 50% against a length of at least one of a major or minor axis of an approximately elliptical shape formed on the light combining member by the first illumination light transmitted through the transmission section; a shaping lens for modifying the beam of the second illumination light emitted from the second light source section so that the beam may be substantially equal to the reflection section of the light combining member in shape and size; and a condenser lens for converging the combined light formed by the light combining member so that a beam of the combined light may have a size substantially identical to a size of an entrance face of a light guide in an endoscope, and the beam of the second illumination light in the combined light may be incident on a center of the entrance face of the light guide. |