Compact folded tele cameras
Folded digital cameras, comprising a lens with N≥3 lens elements L i and having an EFL, an aperture diameter DA, a f-number f/#, a TTL, and a BFL, wherein each lens element has a respective focal length f i and wherein a first lens element L 1 faces an object side and a last lens element L N faces an image side; an image sensor having a sensor diagonal (SD); and an optical path folding element (OPFE) for providing a folded optical path between an object and the image sensor, wherein the lens is located at an object side of the OPFE, wherein the EFL is in the range of 8 mm<EFL<50 mm, and wherein a ratio between the BFL and the TTL fulfills BFL/TTL>0.75.
1 . A camera, comprising:
a lens having an optical axis (OA), N=3 lens elements L i wherein i=1, 2, 3, an effective focal length (EFL), a total track length (TTL) and a back focal length (BFL), wherein a first lens element L 1 faces an object side and a last lens element L 3 faces an image side;
an image sensor;
an optical path folding element (OPFE) for providing a folded optical path between an object and the image sensor by folding light from a first optical path (OP 1 ) that is parallel to the OA to a second optical path (OP 2 ) that is perpendicular to the image sensor; and
an optical element located between the OPFE and the image sensor,
wherein the OPFE has a reflective surface,
wherein the lens is located at an object side of the OPFE,
wherein the camera is a folded digital camera,
wherein the EFL is in the range of 8 mm<EFL<35 mm,
wherein BFL/TTL>0.5, and
wherein the camera is incorporated in a mobile device.
2 . The camera of claim 1 , wherein BFL/TTL>0.7.
3 . The camera of claim 1 , wherein the camera has a first module region with a module region height (MH) measured along OP 1 and a second shoulder region with a shoulder region height (SH) measured along OP 1 , and wherein MH>SH.
4 . The camera of claim 3 , wherein 6 mm<MH<11 mm.
5 . The camera of claim 3 , wherein the camera has an aperture diameter (DA) defining an f number of the camera, and wherein DA>SH−3 mm.
6 . The camera of claim 3 , wherein the mobile device has a device thickness (T) and a camera bump region protruding from the mobile device by a bump height (B), both T and B measured along OP 1 , and wherein the first module region is incorporated in the camera bump region.
7 . The camera of claim 6 , wherein at least part of the second shoulder region is not incorporated in the camera bump region.
8 . The camera of claim 1 , wherein the BFL has a first BFL section (BFL 1 ) parallel to OP 1 and a second BFL section (BFL 2 ) parallel to OP 2 , wherein BFL=BFL 1 +BFL 2 , and wherein BFL 2 /TTL>0.4.
9 . The camera of claim 1 , wherein a ratio of the EFL and a lens thickness (LT) measured along OP 1 fulfills EFL/LT>3.
10 . The camera of claim 1 , wherein an Abbe number of L 1 is larger than an Abbe number of both L 2 and L 3 .
11 . The camera of claim 1 , wherein the OPFE is oriented at an angle β>45 degrees with respect to the lens OA such that OP 1 and OP 2 form an angle of less than 90 degrees.
12 . The camera of claim 11 , wherein β≤60 degrees.
13 . The camera of claim 1 , wherein the camera has an f number (f/#), and wherein f/#<4.5.
14 . The camera of claim 1 , wherein L 1 has a positive lens power and wherein the second lens element L 2 has a negative lens power.
15 . The camera of claim 1 , wherein a lens element is a cut lens element, and wherein a cut lens element is cut along an axis parallel to OP 1 .
16 . The camera of claim 1 , wherein a lens element is movable relative to the OPFE and to the image sensor for focusing.
17 . The camera of claim 1 , wherein a lens element is movable relative to the OPFE and to the image sensor for optical image stabilization.
18 . The camera of claim 1 , wherein L 1 is made of glass.
19 . The camera of claim 1 , wherein 10 mm<EFL<25 mm.
20 . The camera of claim 1 , wherein the mobile device is a smartphone.