US 11,927,828 B2
Optical imaging system including seven lenses of +−−−+−+or +−−++−+refractive powers
Kyu Min Chae, 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 Jan. 27, 2022, as Appl. No. 17/585,995.
Application 17/585,995 is a continuation of application No. 16/365,934, filed on Mar. 27, 2019, granted, now 11,269,160.
Claims priority of application No. 10-2018-0081061 (KR), filed on Jul. 12, 2018.
Prior Publication US 2022/0146788 A1, May 12, 2022
Int. Cl. G02B 13/00 (2006.01); G02B 9/64 (2006.01)
CPC G02B 9/64 (2013.01) [G02B 13/0045 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An optical imaging system comprising:
a first lens having a positive refractive power and a convex object-side surface in an optical axis region thereof;
a second lens having a negative refractive power, a convex object-side surface in an optical axis region thereof and a concave image-side surface in an optical axis region thereof;
a third lens having a refractive power;
a fourth lens having a negative refractive power;
a fifth lens having a convex image-side surface in an optical axis region thereof;
a sixth lens having a negative refractive power and a concave image-side surface in an optical axis region thereof; and
a seventh lens having a convex object-side surface in an optical axis region thereof,
wherein the first to seventh lenses are sequentially disposed in ascending numerical order from an object side of the optical imaging system toward an imaging plane of the optical imaging system,
the optical imaging system has a total number of seven lenses having a refractive power,
a distance from the image-side surface of the sixth lens to the object-side surface of the seventh lens along an optical axis of the optical imaging system is greater than a distance from the image-side surface of the fifth lens to an object-side surface of the sixth lens along the optical axis,
a radius of curvature of an object-side surface of the fifth lens at the optical axis is greater than a radius of curvature of an image-side surface of the third lens at the optical axis,
a radius of curvature of the object-side surface of the second lens at the optical axis is greater than a radius of curvature of the object-side surface of the sixth lens at the optical axis,
a sum of an Abbe number of the second lens and an Abbe number of the third lens is within a range of 60 to 100, and
a distance from an image-side surface of the fourth lens to the object-side surface of the fifth lens along the optical axis is equal to or greater than a distance from an image-side surface of the first lens to the object-side surface of the second lens along the optical axis.