US 12,253,658 B2
Imaging lens and imaging apparatus
Takashi Saotome, Kyoto (JP); Daisuke Kanai, Kyoto (JP); Takaharu Fujii, Kyoto (JP); Satoru Kihara, Kyoto (JP); and Kousuke Sugiki, Kyoto (JP)
Assigned to KYOCERA CORPORATION, Kyoto (JP)
Filed by KYOCERA CORPORATION, Kyoto (JP)
Filed on Dec. 23, 2021, as Appl. No. 17/561,628.
Application 17/561,628 is a continuation of application No. PCT/JP2020/025089, filed on Jun. 25, 2020.
Claims priority of application No. 2019-119161 (JP), filed on Jun. 26, 2019.
Prior Publication US 2022/0121017 A1, Apr. 21, 2022
Int. Cl. G02B 13/04 (2006.01); G02B 5/20 (2006.01); G02B 9/10 (2006.01); G02B 9/62 (2006.01); G02B 13/00 (2006.01)
CPC G02B 13/04 (2013.01) [G02B 9/10 (2013.01); G02B 9/62 (2013.01); G02B 13/0045 (2013.01); G02B 5/208 (2013.01); G02B 13/006 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An imaging lens comprising, in order from an object side:
a front group having negative power;
an aperture stop; and
a rear group having positive power,
wherein in the front group, a first lens surface closest to the object side has a convex shape toward the object side,
wherein in the rear group, a second lens surface closest to the object side has a convex shape toward the object side, a third lens surface closest to an image side has a convex shape toward the image side, and the third lens surface has a coating that filters infrared wavelength,
wherein a curvature radius of the second lens surface is represented by Rr, a curvature radius of the third lens surface is represented by Re, a distance from the second lens surface to the third lens surface on an optical axis is represented by Da, and the following condition (1) is satisfied:

OG Complex Work Unit Math
wherein the front group includes, in the order from the object side,
a concave meniscus-shaped first lens having the first lens surface, and
a concave meniscus-shaped second lens, wherein the concave meniscus-shaped second lens is arranged with a convex surface facing the image side,
wherein the rear group includes, in the order from the object side,
a third lens having the second lens surface,
a fourth lens, and
a cemented lens, and
wherein the third lens, the fourth lens, and the cemented lens all have positive power.