Patent ID: 9477081
Filing Date: 2016-10-25
CPC Classification: G02B

Claim Text:
1. An imaging lens, consisting of a first lens group, a stop, and a second lens group having a positive refractive power, in order from the object side, wherein: the first lens group is composed of a first front lens group having a negative refractive power and a first rear lens group having a positive refractive power, in order from the object side; the first front lens group at least includes four negative lenses and at least two of the negative lenses included in the first front lens group satisfy a conditional expression (1) given below; and the first rear lens group is composed of a cemented lens formed of a negative lens and a positive lens and satisfies a conditional expression (4) given below: where, νd1n: Abbe number of the lens concerned with respect to the d-line, T12: thickness of the first rear lens group on the optical axis, and f: focal length of the entire system.