Patent ID: 11899176
Assignee: APPLE INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A lens system, comprising:
a plurality of optical elements arranged along an optical axis of the lens system, wherein the plurality of optical elements includes, in order along the optical axis from an object side to an image side of the lens system:
a front aperture stop;
a first refractive lens element L1;
a second refractive lens element L2;
a third refractive lens element L3;
a fourth refractive lens element L4; and
a fifth refractive lens element L5;

wherein F-number of the lens system is less than or equal to 2.4, and full field of view of the lens system is greater than or equal to 82 degrees;
wherein respective Abbe numbers for L1, L3 and L5 are higher than respective Abbe numbers for L2 and L4; and
wherein L5 satisfies the relationships:

|fsys/f5|<0.55

(R9+R10)/(R9−R10)>4

where fsys is effective focal length of the lens system, f5 is effective focal length of L5, and R9 and R10 are radius of curvature of an object side surface and an image side surface of L5, respectively.