Illumination lens and endoscope

摘要

An illumination lens to be disposed in a front end of a light guide of an endoscope includes an entrance face and an exit face. The entrance face has positive power. The exit face has positive power. The following Expression (1) is satisfied while the following Expression (2) is satisfied.
1.2<1/r1×φ<1.8,  (1)0.24<1/r2×φ<0.96,  (2)
where φ [mm] is a diameter of the lens, r1 [mm] is a curvature radius of the entrance face, and r2 [mm] is a curvature radius of the exit face.

主权项

1. An illumination lens to be disposed in a front end of a light guide of an endoscope, comprising:
an entrance face that has positive refractive power; and an exit face that has positive refractive power, wherein the following Expression (1) is satisfied while the following Expression (2) is satisfied
1.2<1/r1×φ<1.8,  (1)0.24<1/r2×φ<0.96,  (2) where φ [mm] is a diameter of the lens, r1 [mm] is an absolute value of a curvature radius of the entrance face, and r2 [mm] is an absolute value of a curvature radius of the exit face, wherein the entrance face includes a light diffusing face, and wherein the illumination lens consists of one positive lens.