公开(公告)号：US20200319437A1

公开(公告)日：2020-10-08

申请号：US16838481

申请日：2020-04-02

Applicant: SHOWA OPTRONICS CO., LTD.

Inventor： Noboru Koizumi ,  Takao Tanabe ,  Masaya Ishii

IPC: G02B15/177 ,  G02B9/64 ,  G02B27/00 ,  G02B13/14

Abstract: A short-wavelength infrared imaging lens includes first and second lens groups arranged in order from an object side. The first lens group has a negative refractive power as a whole. The second lens group has a positive refractive power as a whole and includes at least one positive lens that satisfies following conditional expressions (1) and (2): V2p>40  (1) N2p>1.7  (2) Here, N2p is a refractive index N [1.53] of the positive lens at a wavelength of 1.53 μm, and the Abbe number V2p is an Abbe number of the positive lens in a short-wavelength infrared range and is defined as (N [1.53]−1)/(N [0.9]−N [2.325]) when refractive indexes of the at least one positive lens at wavelengths of 0.9 μm, 1.53 μm, and 2.325 μm are represented by N [0.9], N [1.53], and N [2.325], respectively.