Patent ID: 11971521
Assignee: ZHEJIANG SUNNY OPTICAL CO., LTD
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. An optical imaging system, comprising, sequentially from an object side to an image side along an optical axis, a first lens, a second lens, a third lens and a fourth lens,
wherein,
the first lens has negative refractive power, a convex object-side surface, and a concave image-side surface;
the second lens has refractive power;
the third lens has refractive power; and
the fourth lens has positive refractive power, a convex object-side surface, and a concave image-side surface,
wherein 1.5<TTL/ImgH<2.5, where TTL is a distance along the optical axis from the object-side surface of the first lens to an imaging plane of the optical imaging system, and ImgH is half of a diagonal length of an effective pixel area on the imaging plane of the optical imaging system.