US 11,754,812 B2
Imaging lens
Hitoshi Hirano, Tokyo (JP)
Assigned to TOKYO VISIONARY OPTICS CO., LTD., Tokyo (JP)
Filed by TOKYO VISIONARY OPTICS CO., LTD., Tokyo (JP)
Filed on Mar. 26, 2021, as Appl. No. 17/213,382.
Application 17/213,382 is a continuation of application No. 16/722,032, filed on Dec. 20, 2019, granted, now 11,016,272.
Claims priority of application No. 2018-248774 (JP), filed on Dec. 29, 2018.
Prior Publication US 2021/0223518 A1, Jul. 22, 2021
Int. Cl. G02B 9/64 (2006.01); G02B 13/00 (2006.01)
CPC G02B 13/0045 (2013.01) [G02B 9/64 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An imaging lens comprising:
a first lens having positive refractive power;
a second lens;
a third lens;
a fourth lens;
a fifth lens;
a sixth lens;
a seventh lens;
an eighth lens; and
a ninth lens, arranged in this order from an object side to an image plane side,
wherein said imaging lens has a total of nine lenses,
said eighth lens has at least one aspheric surface,
said ninth lens is formed in a shape so that a surface thereof on the image plane side has an aspherical shape, and
said ninth lens is formed in the shape so that the surface thereof on the image plane side has a paraxial curvature radius R9r so that the following conditional
expression is satisfied:
0.2<R9r/f<0.6,
where f is a focal length of a whole lens system.