Patent ID: 7218454

Claim:
An endoscope objective lens comprising, successively from the object side: a first lens directing its concave surface to the image side; a second lens made of a positive meniscus lens directing its convex surface to the image side; a third lens made of a planoconvex lens directing its convex surface to the object side; and a stop placed between the first lens and the second lens; wherein the following Conditional Expressional expressions (1) to (4) are satisfied: 2.00 <|f 1 /f|< 3.00 (1) 0.50 <|f 2 /f 3 |<0.70 (2) 2.00 <|f 1 /d 1-2 |<5.00 (3) 0.40 <|R 2R /R 2F |<0.60 (4) and wherein f: Focal length of the whole system, f 1 : Focal length of the first lens, f 2 : Focal length of the second lens, f 3 : Focal length of the third lens, d 1-2 : Air gap between the first lens and the second lens, R 2F : Radius of curvature of the object-side surface of the second lens, R 2R : Radius of curvature of the image-side surface of the second lens.