OPTICAL DEVICE FOR ENDOSCOPE, ILLUMINATING DEVICE FOR ENDOSCOPE, PHOTOGRAPHING DEVICE FOR ENDOSCOPE, AND ENDOSCOPE

摘要

PROBLEM TO BE SOLVED: To provide stable light distribution characteristics by using a lens molded by the use of two preforms. SOLUTION: An illuminating optical system 33 for an endoscope comprises an illumination lens 34 and a fiber bundle 30. The illumination lens 34 is configured such that an incident surface facing an emitting end face 30a of the fiber bundle 30 is a convex aspherical surface r2. Light passing through an entire surface of the aspherical surface r2 is utilized as illuminating light. A shape unstable portion is caused in an outer circumference portion 53 on the aspherical surface r2 because of a problem on molding. Then, a light shielding ring 55 is provided between the illumination lens 34 and the emitting end face 30a. The light shielding ring 55 covers the outer circumference portion 53 and intercepts light incident on the outer circumference portion 53. COPYRIGHT: (C)2010,JPO&INPIT