Patent ID: 9201218
Filing Date: 2015-12-01
Classification: G02B

Abstract:
1. An imaging lens with a fixed focal length and consisting of five lenses, namely: a first lens having a positive refractive power; a second lens having a negative refractive power; a third lens having a negative refractive power; a fourth lens having a negative refractive power; a fifth lens having a negative refractive power and an inflection point on the surface thereof toward the image side, provided in this order from the object side; all of the first lens through the fifth lens being single lenses; and the imaging lens satisfying the following conditional formulae: wherein Nd2 is the refractive index of the second lens with respect to the d line, f234 is the combined focal length of the second lens, the third lens, and the fourth lens, f is the fixed focal length of the entire system, and νd4 is the Abbe's number of the fourth lens with respect to the d line.