US 12,287,462 B2
Lens system, imaging device, and imaging system
Hiroyuki Shobayashi, Osaka (JP); Yoshio Matsumura, Osaka (JP); Takuya Imaoka, Kanagawa (JP); and Tomoko Iiyama, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed on Mar. 28, 2022, as Appl. No. 17/705,745.
Application 17/705,745 is a continuation of application No. PCT/JP2020/023590, filed on Jun. 16, 2020.
Claims priority of application No. 2019-179904 (JP), filed on Sep. 30, 2019.
Prior Publication US 2022/0221694 A1, Jul. 14, 2022
Int. Cl. G02B 13/00 (2006.01); G02B 3/00 (2006.01); G02B 3/02 (2006.01); G02B 13/08 (2006.01)
CPC G02B 13/0045 (2013.01) [G02B 3/005 (2013.01); G02B 3/02 (2013.01); G02B 13/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A lens system comprising:
a plurality of lens elements arranged from an object side to an image plane side; and
a diaphragm arranged between the plurality of lens elements,
wherein the plurality of lens elements include a plurality of freeform lenses each having a freeform surface that is asymmetrical with respect to a first direction and a second direction which cross with each other,
at least one freeform lens is placed on the image plane side of the diaphragm, and
at least one freeform lens satisfying a conditional expression (1) given below is placed on the object side of the diaphragm;
0.3<T1/T2<0.76  (1)
where
T1: a lens thickness in the first direction at a maximum height of an axial ray that passes through the lens system along with an optical axis of the lens system, and
T2: a lens thickness in the second direction at the maximum height of the axial ray that passes through the lens system along with the optical axis of the lens system.