Folded camera lens designs
Digital cameras, optical lens modules for such digital cameras and methods for assembling lens elements in such lens modules. In various embodiments, the digital cameras comprise an optical lens module including N≥3 lens elements L i , each lens element comprising a respective front surface S 2i−1 and a respective rear surface S 2i . In various embodiments the first lens element toward the object side, L 1 and its respective front surfaces S 1 have optical and/or mechanical properties, such as a clear aperture, a clear height and a mechanical height that are larger than respective properties of following lens elements and surfaces. This is done to achieve a camera with large aperture stop, given a lens and/or camera height.
1. An optical lens module, comprising N lens elements L 1 to L N , wherein N=4 or 5, wherein each lens element L i has a height H Li for 1≤i≤N, and wherein H L1 =H LN >H L2 , wherein each lens element comprises a respective front surface S 2i−1 and a respective rear surface S 2i , the lens element surfaces marked S k where 1≤k≤2 N , wherein each lens element surface has a clear aperture value CA(S k ), wherein the optical lens module is included in a digital camera together with an image sensor that has a sensor diagonal SD, and wherein a ratio CA(S 2N )/SD between the clear aperture value of a rear surface of last lens element CA(S 2N ) and SD is smaller than 0.8.
2. The optical lens module of claim 1 , wherein H L1 >H Li for 3≤i≤N−1.
3. The optical lens module of claim 1 , wherein the clear aperture value CA(S 1 ) of surface S 1 is greater than a clear aperture value of each of surfaces S 2 to S 2N .
4. The optical lens module of claim 1 , further comprising a lens barrel having a barrel height H and wherein H LN ≥H.