US 11,719,910 B2
Telescopic optical imaging system
Jin Hwa Jung, Suwon-si (KR); and Yong Joo Jo, Suwon-si (KR)
Assigned to Samsung Electro-Mechanics Co., Ltd., Suwon-si (KR)
Filed by Samsung Electro-Mechanics Co., Ltd., Suwon-si (KR)
Filed on Dec. 30, 2020, as Appl. No. 17/137,502.
Application 17/137,502 is a continuation of application No. 16/129,888, filed on Sep. 13, 2018, granted, now 10,908,389.
Claims priority of application No. 10-2017-0148960 (KR), filed on Nov. 9, 2017; and application No. 10-2018-0007785 (KR), filed on Jan. 22, 2018.
Prior Publication US 2021/0116680 A1, Apr. 22, 2021
Int. Cl. G02B 9/62 (2006.01); G02B 27/00 (2006.01); G02B 7/02 (2021.01); G02B 13/00 (2006.01)
CPC G02B 9/62 (2013.01) [G02B 7/021 (2013.01); G02B 13/0045 (2013.01); G02B 27/0037 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An optical imaging system comprising:
a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens sequentially arranged on an optical axis from an object side to an image side,
wherein an image-side surface of the first lens and an image-side surface of the sixth lens are concave,
wherein a radius of curvature of an object-side surface of the fourth lens is greater than a radius of curvature of an image-side surface of the first lens, and
0.7<TL/f<1.0 and |Nd2−Nd3|<0.2 in which TL is a distance from an object-side surface of the first lens to an imaging plane, f is an overall focal length of the optical imaging system, Nd2 is a refractive index of the second lens, and Nd3 is a refractive index of the third lens.