Patent ID: 8035900

Claim:
An objective lens for an endoscope, comprising a lens group A and a lens group B that are movable in a direction of an optical axis, wherein first focal adjustment for observing a point between a most-distant point and an intermediate point is performed by moving the lens group A from a lens arrangement for observing the most-distant point; second focal adjustment for observing a point between the intermediate point to a nearest point is performed by moving the lens group B from a lens arrangement for observing the intermediate point; and the objective lens satisfies conditional expressions (1) and (2): 1.2 <f M /f F (1) 0.9 <|f N /f M |<1.1 (2) wherein f M represents a focal length of the objective lens in observing the intermediate point, f F represents a focal length of the objective lens in observing the most-distant point, and f N represents a focal length of the objective lens in observing the nearest point.