US 12,235,416 B2
Optical imaging system
Yang Li, Yuyao (CN); Lingbo He, Yuyao (CN); Fujian Dai, Yuyao (CN); and Liefeng Zhao, Yuyao (CN)
Assigned to Zhejiang Sunny Optical Co., Ltd, Zhejiang (CN)
Filed by Zhejiang Sunny Optical Co., Ltd, Zhejiang (CN)
Filed on Mar. 3, 2022, as Appl. No. 17/685,949.
Claims priority of application No. 202110249324.9 (CN), filed on Mar. 8, 2021.
Prior Publication US 2022/0283410 A1, Sep. 8, 2022
Int. Cl. G02B 13/00 (2006.01); G02B 9/64 (2006.01)
CPC G02B 13/0045 (2013.01) [G02B 9/64 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An optical imaging system, comprising, sequentially along an optical axis from an object side to an image side:
a stop;
a first lens, having a positive refractive power;
a second lens, having negative refractive power;
a third lens, having a positive refractive power or a negative refractive power;
a fourth lens, having a negative refractive power, an object-side surface of the fourth lens is a convex surface;
a fifth lens, having a negative refractive power;
a sixth lens, having a positive refractive power or a negative refractive power; and
a seventh lens, having a positive refractive power or a negative refractive power,
wherein, one of the first to seventh lenses is an aspheric lens made of glass;
an effective focal length f4 of the fourth lens, an effective focal length f2 of the second lens, and an effective focal length f3 of the third lens satisfy: 5.0<|f4/f2−f3/f2|<10.0; and
a radius of curvature R2 of an image-side surface of the first lens and a radius of curvature R1 of an object-side surface of the first lens satisfy:
2.5≤(R2+R1)/(R2−R1)<3.0.