Folded camera lens designs
Folded lens modules and assemblies characterized by low height and large entrance pupil (clear aperture), designed for folded cameras in consumer electronics and specifically in mobile phones. In some embodiments, a folded lens assembly comprises a plurality of lens elements that include, in order for an object side to an image side, a first lens element L 1 with a clear aperture CA(S 1 ) and a second lens element L 2 with a clear aperture CA(S 3 ), wherein CA(S 1 )/CA(S 3 )>1.2 and wherein the lens assembly has a ratio between an image sensor diagonal length SDL and a clear aperture of a last lens element surface CA(S 2N ), SDL/CA(S 2N )>1.5.
1. A folded lens assembly for a folded camera, consisting of: N=5 lens elements that include, in order for an object side to an image side, a first lens element L 1 with a first lens element surface clear aperture CA(S 1 ), a second lens element L 2 with a second lens element surface clear aperture CA(S 3 ), and a fifth lens element with negative refractive power, wherein CA(S 1 )/CA(S 3 )>1.2, and wherein the lens assembly has a ratio between an image sensor diagonal length SDL and a clear aperture of a last lens element surface CA(S 2N ), SDL/CA(S 2N )>1.5, wherein the first lens element has positive refractive power and the second lens element has negative refractive power, and wherein the N lens elements further include a third lens element with positive refractive power and a fourth lens element with negative refractive power.
2. A folded lens assembly for a folded camera, consisting of: N=5 lens elements that include, in order for an object side to an image side, a first lens element L 1 with a first lens element surface clear aperture CA(S 1 ), a second lens element L 2 with a second lens element surface clear aperture CA(S 3 ), and a fifth lens element with negative refractive power, wherein CA(S 1 )/CA(S 3 )>1.2, and wherein the lens assembly has a ratio between an image sensor diagonal length SDL and a clear aperture of a last lens element surface CA(S 2N ), SDL/CA(S 2N )>1.5, wherein the lens assembly has a total track length (TTL) and a back focal length (BFL) and wherein a ratio BFL/TTL>0.35, wherein the TTL is a distance from the first surface S 1 of the first lens element to an image sensor, and wherein the BFL is a distance from a last surface of a last lens element S 2N to the image sensor.
3. The folded lens assembly of claim 2 , wherein an optical window is positioned in a path defining the BFL and the TTL.