| 摘要 |
PURPOSE:To obtain uniform flux distribution in the visual field of the endoscope by composing a coupling optical system of at least one convex lens and one concave lens and arranging this system between the transmission-side and photodetection-side light guides of the optical lighting system for the endoscope. CONSTITUTION:The optical coupling system arranged between the transmission- side light guide 1 and photodetection-side light guide 2 of the optical lighting system for the endoscope consists of at least one convex lens 4 and at least one concave lens 5, thus constituting a nearly afocal system. The afocal system converts only angular magnification and does not vary the angle between incident light and emitted light, so there is no unevenness of light incident on the projection end surface of the photodetection-side light guide 2 corresponding to the angle even if there is unevenness of the intensity distribution of light on the projection end surface of the transmission-side light guide 1, and consequently the projection light of the photodetection-side light guide 2 has no unevenness.
|
