Aspherical fiber coupling lens

Abstract

An aspherical fiber coupling lens applied to a photoelectric coupling module is disclosed. The spherical fiber coupling lens is a bi-convex lens with positive refraction power and having a first optical surface and a second optical surface, both are aspherical surfaces while optical features of the lens satisfy the following conditions: 0.5 < d 2 f < 1.5 ; 1.0 < R 1 - R 2 R 1 + R 2 < 2.0 ; 1.2 < ( 1 R 1 - 1 R 2 ) · f < 2.2 wherein f is the effective focal length of the lens, d2 is thickness of the lens on optical axis, Nd is refraction index of the lens, R1, R2 respectively are curvature radiuses of the first optical surface and the second optical surface of the lens. Thereby the lens has features of small focus, compact volume and high coupling efficiency so that applications of the photoelectric coupling module are improved.

Dependencies are inferred from the claim text.