Large-Field-Of-View Lens System For Capsule Endoscope And Capsule Endoscope Having Large-Field-Of-View Lens System

摘要

A lens system and a for a capsule endoscope includes a first lens having a concave aspheric surface having a radius R2 and a second lens having a convex aspheric surface having a radius R3 facing the first lens. A third lens has a convex aspheric surface having radius R6. The lens system satisfies the following conditions: (1) R2/Gap1 and ABS(R3/R2)1.28; (2) 1ABS(R6/R2)1.1 and R60; and (3) V2V1 and V2V3; wherein: i) Gap is a distance from a center of curvature of the concave aspheric surface of the first lens to a center of curvature of the convex aspheric surface of the second lens; (ii) ABS denotes absolute value; and (iii) V1 is an Abbe number of the first lens, V2 is an Abbe number of the second lens, and V3 is an Abbe number of the third lens.