US 11,726,304 B2
Folded optical systems
Takeyoshi Saiga, Tokyo (JP)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on May 24, 2021, as Appl. No. 17/329,009.
Claims priority of provisional application 63/030,224, filed on May 26, 2020.
Prior Publication US 2021/0382269 A1, Dec. 9, 2021
Int. Cl. G02B 13/10 (2006.01); G02B 13/00 (2006.01); G03B 17/17 (2021.01)
CPC G02B 13/007 (2013.01) [G02B 13/003 (2013.01); G03B 17/17 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An optical system, comprising:
in order from an object side of the optical system to an image side of the optical system:
a first lens group comprising a power prism that includes a first surface, a second surface, and a third surface on an optical axis of the optical system, wherein the first surface is a transmissive aspherical surface that provides positive refractive power for the prism, wherein the second surface is a reflective surface that folds the optical axis of the optical system, and wherein the third surface is a transmissive surface; and
a second lens group comprising two or more refractive lenses; and
wherein the optical system satisfies the conditional expressions:
0.6<B/A<2.3,
where A is power of the optical system, and B is power of the first lens group, and
−0.2<CD<0.1,
where C is power of the second lens group, and D is length of the second lens group.