COMPACT DOUBLE FOLDED TELE CAMERAS

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional patent applications No. 63/274,700 filed November 2, 2021 and 63/288,047 filed December 10, 2021, both of which are incorporated herein by reference in their entirety.

FIELD

The presently disclosed subject matter is generally related to the field of digital cameras and in particular to folded digital cameras for use in mobile electronic devices such as smartphones.

DEFINITIONS

In this application and for optical and other properties mentioned throughout the description and figures, the following symbols and abbreviations are used, all for terms known in the art:

Lens element: a single lens element.

Lens: assembly of a plurality of lens elements.

Total track length (TTL): the maximal distance, measured along an axis parallel with the optical axis of a lens, between a point of the front surface Si of a first lens element Li and an image sensor, when the system is focused to an infinity object distance.

Back focal length (BFL): the minimal distance, measured along an axis parallel with the optical axis of a lens, between a point of the rear surface S2N of the last lens element LN and an image sensor, when the system is focused to an infinity object distance.

Effective focal length (EFL): in a lens (assembly of lens elements Li to LN), the distance between a rear principal point P' and a rear focal point F' of the lens. f-number (f/#): the ratio of the EFL to an entrance pupil (or aperture) diameter of a lens. BACKGROUND

Multi-aperture cameras (or “multi-cameras”, of which a “dual-cameras” having two cameras is an example) are today’s standard for portable electronic mobile devices (“mobile devices”, e.g. smartphones, tablets, etc.). A multi-camera setup usually comprises a wide field- of-view (or “angle”) FOVw camera (“Wide” camera or “W” camera), and at least one additional camera, e.g. with a narrower (than FOVw) FOV (Telephoto or “Tele” camera with FOVT).

FIG. 1A exemplarily illustrates a known folded Tele camera 100 comprising an optical path folding element (OPFE) 102, a lens 104 including N=4 lens elements Li - L4, lens 104 being included in a lens barrel 110, and an image sensor 106. Lens 104 has an optical lens height HL, measured along OP 112. HL defines an aperture diameter (DA) of lens 104 along the z-direction in the YZ coordinate system shown. Lens 104 may be a cut lens, including one or more cut lens elements Li (see FIG. ID). OPFE 102 folds an optical path (OP) from a first OP 112 (in the z direction) to a second OP 108 parallel with an optical axis of lens 104 along the y axis in the coordinate system shown. Lens 104 is located at an image side of OPFE 102. Both the 1 I L and the BFL of camera 100 are oriented along a dimension parallel with OP 108 (in this case, the y-axis). A theoretical limit for a height of a camera module (“minimum module height” or “MHM”) including camera 100 is shown. MHM is defined by the largest dimension along OP 112 of a component included in camera 100. HL is limited by MHM, i.e. HL < MHM.

FIG. IB illustrates a known dual -camera 150 that comprises folded Tele camera 100 and a (vertical or upright) Wide camera 130 that includes a Wide lens 132 and a Wide image sensor 138. Lens 132 is included in a lens barrel 134. Wide camera 130 has an OP 136 which is substantially parallel with OP 112.

FIG. 1C shows an example of a known double folded camera numbered 160 in a cross- sectional view. Camera 160 includes a first object-sided OPFE (“O-OPFE”, for example a prism) 162, a lens 164 including a plurality of lens elements, a second image-sided OPFE (“I- OPFE”- for example a mirror) 166, and an image sensor 168. The optical path of camera 160 is folded twice, from a first OP 172, which is substantially parallel with the y-axis in the XYZ coordinate system shown, to a second OP 174, which is substantially parallel with the x-axis, to a third OP 176, which is substantially parallel with the y-axis. Image sensor 168 is oriented in a plane parallel with the x-z plane. O-OPFE 162 and I-OPFE 166 are oriented at an angle of 45 degrees with respect to OP 172 and OP 174.

FIG. ID shows a known cut lens element 180 in a cross-sectional view. Lens element 180 may define an aperture of an optical lens system including lens element 180. Lens element 180 is cut by 20%, i.e. its optical width WL is 20% larger than its optical height HL. This means that also the aperture of the optical lens system changes accordingly, so that the aperture is not axial symmetric. The cutting allows for a small HL, which is required for small MHM (see FIG. 1A), and still relatively large effective aperture diameters (DAs) that satisfy DA> HL. AS defined above, f/# = EFL/DA. As known, a low f/# is desired as it has 3 major advantages: good low light sensitivity, strong “natural” Bokeh effect, and high image resolution.

It is noted that herein, “aperture” refers to an entrance pupil of a lens (or “lens assembly”). If it is referred to an “aperture of a camera” or an “aperture of an optical lens system”, this always refers to the aperture of the lens included in the camera or in the optical lens system respectively. "Aperture” and "clear aperture” are used interchangeably. In general, in mobile electronic devices (or just “mobile devices”) such as smartphones a double folded camera such as 160 incorporates a relatively small image sensor having a SD of about 5-7mm, and has a relatively small HL of about 4mm-5mm, resulting in a relatively large f/# of about 3-6 and in a relatively small ratio of HL/HM. HM is the height of a camera module including a double folded camera such as 160, HM may be about 5mm- 15mm. HM is connected to the minimum module height (“MHM“, see FIG. 1 A) by HM = MHM + height penalty (“penalty”), the penalty being about 1mm - 2mm.

It would be beneficial to have a mobile device compatible double folded Tele camera that incorporates large image sensors and provides large DAs to achieve large HL/MHM ratios tat simultaneously allow for a low f/# and a slim camera design.

SUMMARY

In various exemplary embodiments, there are provided camera modules, comprising: a lens with N = 6 lens elements Li divided into a first lens group (Gl) and a second lens group (G2) and having an effective focal length EFL, an aperture diameter DA, a f-number 17#, a total track length 1 I L and a back focal length BFL, wherein each lens element has a respective focal length fi and wherein a first lens element Li faces an object side and a last lens element LN faces an image side; an object side-optical path folding element O-OPFE for folding a first optical path (OP1) to a second optical path (OP2); an image side-optical path folding element I-OPFE for folding OP2 to a third optical path (OP3), wherein OP1 and OP2 are perpendicular to each other and wherein OP 1 and OP3 are parallel with each other; and an image sensor having a sensor diagonal (SD), wherein the camera module is a folded digital camera module, wherein G1 is located at an object side of the O-OPFE and G2 is located at an image side of the O- OPFE, wherein the EFL is in the range of 8mm<EFL<50mm, wherein the camera module is divided into a first region having a minimum camera module region height MHM and including G1 and the O-OPFE, and into a second region having a minimum shoulder region height MHs

< MHM and including the I-OPFE and the image sensor, wherein all heights are measured along OP1, wherein an aperture height of the lens is HL and wherein HL/MHS > 0.9.

In some examples, HL/MHS > 1. In some examples, HL/MHS > 1.05. In some examples, HL/MHS > 1.1.

In some examples, EFL > 1.1 MLM. In some examples, EFL > 1.2-MLM. In some examples, EFL > 1.3 MLM.

In some examples, 5mm < SD < 15mm.

In some examples, SD/EFL > 0.3. In some examples, SD/EFL > 0.35. In some examples, SD/EFL > 0.4.

In some examples, a ratio between an optical width of the lens WL and an optical height of the lens HL fulfills WL/HL > 1.1. In some examples, WL/HL > 1.2.

In some examples, EFL/TTL < 1.2.

In some examples, BFL/EFL > 0.25. In some examples, BFL/TTL > 0.3.

In some examples, 15mm < EFL < 40mm. In some examples, 20mm < EFL < 30mm.

In some examples, 5mm < DA < 15mm and 2 < f/# < 6.5. In some examples, 6mm <DA

< 10mm and 2.5 < f/# < 4.5.

In some examples, Gl, the O-OPFE and G2 are movable together along OP2 relative to I-OPFE and the image sensor for focusing.

In some examples, Gl, the O-OPFE, G2 and the I-OPFE are movable together along OP2 relative to the image sensor for optical image stabilization (OIS) around a first OIS axis.

In some examples, Gl, the O-OPFE, and G2 are movable together along OP2 relative to the image sensor for OIS around a first OIS axis.

In some examples, Gl, the O-OPFE, G2 and the I-OPFE are movable together along an axis perpendicular to both OP1 and OP2 relative to the image sensor for OIS around a second OIS axis.

In some examples, Gl, the O-OPFE, and G2 are movable together along OP2 relative to the image sensor for OIS around a second OIS axis.

In some examples, the first region of the camera module has a module region height HM,the second region of the camera module has a shoulder region height Hs, and HM> HS. In some examples, 4mm < Hs < 10mm and 6mm < H\i < 13mm. In some examples, 6mm < Hs < 8mm and 7mm < H\i < 11mm.

In some examples, HS/HM < 0.9. In some examples, HS/HM < 0.8.

In some examples, a ratio between an average lens thickness (ALT) of all lens elements Li -LN and TTL fulfills ALT/TTL < 0.05. In some examples, a ratio of the thickness of LI (Tl) and ALT fulfills Tl/ALT > 2.

In some examples, a distance d5-6 between L5 and L6 and ALT fulfills d5-6/ALT > 1.2.

In some examples, LI is made of glass.

In some examples, ratio between fl of LI and EFL fulfills fl/EFL < 0.75.

In some examples, a ratio between |f6| of L6 and EFL fulfills |f6|/EFL > 0.75.

In some examples, the last lens element LN is negative.

In some examples, G1 has a thickness T-Gl and T-G1/TTL < 0.1.

In some examples, G2 has a thickness T-G2 and T-G2/TTL < 0.1.

In some examples, G1 is a cut lens cut along an axis parallel with OP1.

In some examples, G1 is cut by 20% and MH is reduced by >10% by the cutting relative to an axial symmetric lens having a same lens diameter as the cut lens’ diameter measured along an axis perpendicular to both OP1 and OP2.

In some examples, the O-OPFE and/or the I-OPFE is a mirror.

In some examples, G2 is a cut lens cut along an axis parallel with OP2.

In some examples, G2 is cut by 20% and has a cut lens diameter and MH is reduced by >10% by the cutting relative to an axial symmetric lens having a same lens diameter as the cut lens diameter measured along an axis perpendicular to both OP1 and OP2.

In some examples, the camera module does not include an I-OPFE.

In some examples, OP 1 and OP3 are perpendicular to each other.

In various exemplary embodiments, there are provided mobile devices including a camera module as above, wherein the mobile device has a device thickness T and a camera bump region, wherein the bump region has an elevated height T+B, wherein a first region of the camera module is incorporated into the camera bump region and wherein a second region of the camera module is not incorporated into the camera bump region.

In some examples, the first region of the camera includes the camera module lens, and the second region of the camera includes the camera module image sensor.

In various exemplary embodiments, there are provided lenses with N = 4 lens elements Li having a lens thickness T ens, an EFL, an aperture diameter DA, a f/#, a TTL and a BFL, wherein each lens element has a respective focal length fi and wherein a first lens element Li faces an object side and a last lens element LN faces an image side; an O-OPFE for folding a first optical path (OP1) to a second optical path (OP2); an I-OPFE for folding OP2 to a third optical path (OP3), wherein OP1 and OP2 are perpendicular to each other and wherein OP1 and OP3 are parallel with each other; and an image sensor having a sensor diagonal SD, wherein the camera module is a folded digital camera module, wherein the lens is located at an object side of the O- OPFE, wherein the EFL is in the range of 8mm<EFL<50mm, wherein a ratio between a lens thickness Tiens and the HL, Tiens/TEL < 0.4.

In some examples, T ens/TTL < 0.3. In some examples, T ens/TTL < 0.25.

In some examples, a camera module is divided into a first region having a minimum camera module region height MHM and including the lens and the O-OPFE and into a second region having a minimum shoulder region height MHs < MHM and including the I-OPFE and the image sensor, the camera module having a minimum camera module length MLM, wherein all heights are measured along OP1, wherein a length is measured along OP2, wherein an aperture height of the lens is HL and wherein HL>MHS -1.5mm.

In some examples, HL>MHS -1mm.

In some examples, HL>0.8 MHS. In some examples, HL>0.9 MHS. In some examples, HL>MHS.

In some examples, EFL > 1.1 MLM. In some examples, EFL > 1.2-MLM. In some examples, EFL > 1.3 MLM.

In some examples, TIL > 1.2 MLM. In some examples, TTL > 1.3 -MLM. In some examples, TTL > 1.4-MLM.

In some examples, the lens and the O-OPFE are movable together along OP2 relative to I-OPFE and the image sensor for focusing.

In some examples, the lens is movable along OP1 relative to the O-OPFE, the I-OPFE and the image sensor for focusing.

In some examples, the lens, the O-OPFE and the I-OPFE are movable together along OP2 relative to the image sensor for OIS around a first OIS axis.

In some examples, lens is movable along OP2 relative to the O-OPFE, the I-OPFE and the image sensor for OIS around a first OIS axis.

In some examples, the lens, the O-OPFE and the I-OPFE are movable together along an axis perpendicular to both OP 1 and OP2 relative to the image sensor for OIS around a second OIS axis. In some examples, the lens is movable along an axis perpendicular to both OP1 and OP2 relative to the O-OPFE, the I-OPFE and the image sensor for OIS around a second OIS axis.

In some examples, LI is made of glass and has a refractive index n of n>1.7.

In some examples, fl < EFL/2.

In some examples, a sequence of the power of the lens elements Li - L4 is plus-minus- plus-plus. In some examples, a sequence of the power of the lens elements Li - L4 is plus- minus-plus-minus. In some examples, a sequence of the power of the lens elements Li - L4 is plus-minus-minus-plus.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting examples of embodiments (or “examples”) disclosed herein are described below with reference to figures attached hereto that are listed following this paragraph. The drawings and descriptions are meant to illuminate and clarify embodiments disclosed herein, and should not be considered limiting in any way.

FIG. 1A illustrates a known folded Tele camera;

FIG. IB illustrates a known dual -camera;

FIG. 1C shows schematically a known double folded Tele camera;

FIG. ID shows a known cut lens element in a cross-sectional view;

FIG. 2A shows schematically an embodiment of a double folded Tele camera module disclosed herein;

FIG. 2B shows schematically a mobile device having an exterior surface and including a double folded Tele camera as in FIG. 2A in a cross-sectional view;

FIG. 2C shows schematically an embodiment of a 1G double folded Tele camera module disclosed herein;

FIG. 2D shows schematically a mobile device including a double folded Tele camera as in FIG. 2C in a cross-sectional view;

FIG. 3A shows an embodiment of an optical lens system disclosed herein in a cross- sectional view;

FIG. 3B shows another embodiment of an optical lens system disclosed herein in a cross-sectional view;

FIG. 3C shows yet another embodiment of an optical lens system disclosed herein in a cross-sectional view;

FIG. 3D shows the embodiment of an optical lens system from FIG. 3C in a perspective view;

FIG. 3E shows the embodiment of an optical lens system from FIG. 3C in atop view;

FIG. 4 shows another embodiment of an optical lens system disclosed herein in a cross- sectional view;

FIG. 5 shows yet another embodiment of an optical lens system disclosed herein in a cross-sectional view;

FIG. 6 shows yet another embodiment of an optical lens system disclosed herein in a cross-sectional view;

FIG. 7A shows yet another embodiment of an optical lens system disclosed herein in a cross-sectional view;

FIG. 7B shows a prism of the optical lens system of FIG. 7A in a side view;

FIG. 7C shows a prism of the optical lens system of FIG. 7A in a perspective view;

FIG. 8A shows schematically a method for focusing (or “autofocusing” or “AF”) in an optical lens systems disclosed herein;

FIG. 8B shows schematically a method for performing optical image stabilization (OIS) in a first OIS direction for optical lens systems disclosed herein;

FIG. 8C shows schematically a method disclosed herein for performing OIS in a second OIS direction for optical lens systems disclosed herein.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding. However, it will be understood by those skilled in the art that the presently disclosed subject matter may be practiced without these specific details. In other instances, well-known methods and features have not been described in detail so as not to obscure the presently disclosed subject matter.

FIG. 2A shows schematically an embodiment of a “2 -group” (or “2G”) double folded Tele camera module disclosed herein and numbered 200. Camera module 200 comprises a lens 202 with a plurality of N lens elements (here and for example N=5) numbered Li - LN, with Li being oriented towards an object side. Camera module 200 further comprises an O-OPFE 204 for folding a first optical path OP1 212 to a second optical path OP2 214, an I-OPFE 206 for folding OP2 to a third optical path OP3 216 and an image sensor 208. The camera elements may be included in a module housing 220, as shown. In camera 200, OP1 212 is substantially parallel with the z-axis, and OP2 214 is substantially parallel with the y-axis and OP3 216 is substantially parallel with the z-axis. O-OPFE 204 and I-OPFE 206 form an angle of 45 degrees with both the y-axis and the z-axis. Image sensor 208 is oriented in a plane perpendicular to the z-axis in the shown coordinate system.

In other examples, a camera module such as camera module 200 may not be a double folded Tele camera module, but a (single) folded Tele camera module. I.e. it may not have an OP3 and it may not include an I-OPFE such as I-OPFE 206. In these other examples, OP1 may be oriented perpendicular to OP2 (as shown) and an image sensor such as image sensor 208 may be oriented in a plane perpendicular to the y-axis in the shown coordinate system.

In yet other examples, a camera module such as camera module 200 may be a double folded Tele camera module, but OP3 may be perpendicular to OP1 (not parallel, as shown). In these yet other examples, OP 1 may be parallel to the z-axis, OP2 may be parallel to the y-axis (as shown) and OP3 may be perpendicular to the shown y-z-coordinate system. An image sensor such as image sensor 208 may be oriented in a plane parallel to the shown y-z-coordinate system.

Lens 202 is divided into a first lens group (“Gl”) and a second lens group (“G2”), marked 202-G1 and 202-G2. Gl is located at an object side of O-OPFE 204 and G2 is located at an image side of O-OPFE 204 and at an object side of I-OPFE 206.

Camera module 200 is divided into a first, “module” region including 202-G1 and O- OPFE 204 that has a module region height HM and a minimum module region length RLM (as shown), and a second, “shoulder” region including I-OPFE 206 the image sensor 208 that has a shoulder region height Hs < HM and a shoulder region length Ls. All heights are measured along OP1 212, all lengths are measured along OP2 214.

The optical height and width of lens element Li may define the aperture (having a diameter DA) of camera 200, so that the optical height and the optical width of lens element Li represent also the aperture height and aperture width respectively. The height of lens element Li, HLI, is measured along the y-axis, as shown. This fact and the further design considerations disclosed herein allow the realization of optical systems that provide low f/# and large EFL (i.e. a high zoom factor), given their compact size or dimensions. This is expressed in the two following advantageous values and ratios (see Table 1):

1. An optical height, HL, which is larger than 90% of the minimum shoulder height HMs, HL > 0.9'HMs, or even HL > HMs; 2. An EFL which is larger by 10% (or 20%, or even 30%) than the minimum module length, EFL > 1.1 -MLM.

The H L of camera module 200 is divided into three parts, TTL1 - 1TL3, as shown. The BFL of camera module 200 is divided into two parts, BFL1 and BFL2. A first part TTL1 is parallel with OP1 212, a second part TTL2 and a first part BFL1 are parallel with OP2 214, a third part 1 1L3 and a second part BFL2 are parallel with OP3 216. 1 IL and BFL are obtained by 1 1L=1 1L1+TTL2+1 1L3 and BFL=BFL1+BFL2 respectively.

For estimating theoretical limits for minimum dimensions of a camera module that includes optical lens systems disclosed herein, we introduce the following parameters and interdependencies. “Theoretical limits” means that only the optically operative regions of components included in the optical lens systems disclosed herein are considered.

Minimum module region length MRLM.

MRLM is the theoretical module region length limit of module region 222 having height HM. MRLM is defined by the physical size of the components included in the module region 222.

For 200, MRLM = HGI, i.e. the height of G1 (measured along the y-axis) represents the lower limit for MRLM.

Shoulder region length Ls

The length of shoulder region 224 having height Hs.

Derived from MLs. For achieving a realistic estimation for a camera shoulder length (“Ls”), one may add for example a length of 3 ,5mm to MLs. i.e. Ls = MLs +3 ,5mm. The additional length accounts for a movement stroke that may be required for AF and/or OIS as well as for image sensor packaging, housing, etc. Note that the value of 3.5 mm is exemplary and by no means limiting, and that the addition may vary between 1.5 mm and 10 mm.

In general, from an industrial design point of view it may be beneficial to maximize Ls (minimize MLM).

Minimum module height (“MHM”) and module height HM

MHM is the theoretical module height limit of module region 222 having height HM MHM = HOPFE + ALO + TGI, HOPFE being the height of O-OPFE 204 in a direction parallel with OP1 112 (O-OPFE 204 is oriented at 45 degree with respect to both the y-axis and the z-axis, so that HOPFE= WOPFE) WOPFE being a width of the O-OPFE in a direction parallel with OP2 108, ALO being the distance between the center of G1 and O-OPFE 204 and TGI being the height (or thickness) of G1.

For achieving a realistic estimation for a camera module height, we calculate HM by adding an additional height penalty of 1.5mm to MHM, i.e. HM = MHM + 1.5mm. The penalty accounts for movements that may be required for optical image stabilization (OIS), autofocus (AF) as well as housing, lens cover etc. Note that the value of 1.5 mm is exemplary and by no means limiting, and that the addition may vary between 0.5 mm and 3 mm.

Minimum module length (“MLM”)

MLM is the theoretical module length limit of a module housing 220 having height HM. MLM = MRLM + MLs.

- For achieving a realistic estimation for a camera module length (“LM”), one may add for example a length of 3.5mm to MLM, i.e. LM = MLM +3.5mm.

Minimum shoulder height (“MHs”) and shoulder height Hs

MHs is the theoretical shoulder height limit of shoulder region 224 having height Hs.

For achieving a realistic estimation for shoulder height Hs, we calculate Hs by adding an additional height of 1 ,5mm to MHs, i.e. Hs = MHs + 1.5mm.

In comparison to a known folded camera like camera 100, in camera module 200 image sensor 208 is not oriented parallel to the z-axis, but parallel to the y-axis (in the coordinate system shown). Given a specific Hs, this allows the use of larger image sensors, e.g. image sensors with sensor diagonals (SDs) in the range of about 6mm- 16mm, as the size of the image sensor size is not limited by Hs. Larger image sensors are beneficial in terms of the camera’s image quality, e.g. measured in terms of signal-to-noise ratio (“SNR”).

FIG. 2B shows schematically a cross section of a mobile device 230 (e.g. a smartphone) having an exterior front surface 232 and an exterior rear surface 234 including 2G double folded Tele camera 200. The aperture of camera 200 is located at rear surface 234. Front surface 232 may e.g. include a screen (not visible). Mobile device 230 has a first “regular” region 236 of thickness (“T”) and a second “bump” region 238 that is elevated (protrudes outwardly) by a height B over regular region 236. The bump region has a bump length (“BL”) and a bump thickness T+B. Module region 222 of camera 200 is included in bump region 238. Shoulder region 224 is included in regular region 236. Optionally, in some embodiments, parts of shoulder region 224 may also be included in bump region 238.

For industrial design reasons, a small camera bump region (i.e. a short BL) is desired. A known folded camera such as 100 may be entirely included in bump region 238. In comparison, camera 200, which may be only partially included in bump region 238, allows for a smaller camera bump region (i.e. a shorter BL).

FIG. 2C shows schematically an embodiment of a “1-group” (or “1G”) double folded Tele camera module disclosed herein and numbered 250. Camera module 250 comprises a lens 252 with a plurality of N lens elements (here and for example N=3) numbered Li - LN, with Li being oriented towards an object side. Camera module 250 further comprises an O-OPFE 254 for folding OP1 262 to OP2 264, an I-OPFE 256 for folding OP2 to OP3 266 and an image sensor 258. The camera elements may be included in a module housing 270. In camera 250, OP1 262 is substantially parallel with the z-axis, and OP2 264 is substantially parallel with the y-axis and OP3 266 is substantially parallel with the z-axis. O-OPFE 254 and I-OPFE 256 may or may not form an angle of 45 degrees with both the y-axis and the z-axis. Lens 252 in its entirety is located at an object side of O-OPFE 254. Image sensor 258 is oriented in a plane perpendicular to the z-axis in the shown coordinate system.

In other examples, a camera module such as camera module 250 may not be a double folded Tele camera module, but a (single) folded Tele camera module. I.e. it may not have an OP3 and it may not include an I-OPFE such as I-OPFE 256. In these other examples, OP1 may be oriented perpendicular to OP2 (as shown) and an image sensor such as image sensor 208 may be oriented in a plane perpendicular to the y-axis in the shown coordinate system.

In yet other examples, a camera module such as camera module 250 may be a double folded Tele camera module, but OP3 may be perpendicular to OP1 (not parallel, as shown). In these yet other examples, OP 1 may be parallel to the z-axis, OP2 may be parallel to the y-axis (as shown) and OP3 may be perpendicular to the shown y-z-coordinate system. An image sensor such as image sensor 258 may be oriented in a plane parallel to the shown y-z-coordinate system.

The optical height and width of lens element Li may define the aperture of camera 250. The height of lens element Li, HLI, is measured along the y-axis, as shown. This fact and the further design considerations disclosed herein allow the realization of optical systems that provide low f/#, large EFL (i.e. a high zoom factor) and large TTL, given their compact size or dimensions. In addition, a lens thickness accounts for only a relatively small portion of the TTL. This is expressed in the four following advantageous values and ratios (see Table 1):

1. An optical height, HL, which is larger than 80% of the minimum shoulder height HMs, HL > 0.8-HMs.

2. An EFL which is larger by 10% (or 20%, or even 30%) than the minimum module length, EFL > 1.1 MLM. 3. A TTL which is larger by 20% (or 30%, or even 40%) than the minimum module length, TIL > 1.2-MLM.

4. A small ratio of lens thickness T ens and total track length, TLens/TTL < 0.4 (or < 0.35, or even < 0.3).

Camera module 250 is divided into a module region having a module region height HM and including lens 252 and O-OPFE 254, and a shoulder region having a shoulder region height Hs < HM and including I-OPFE 256 and image sensor 258.

The TIL and the BFL of camera module 250 are divided into three parts, TTL1 - TTL3 and BFL1 - BFL3 respectively, as shown. TTL and BFL are obtained by TTL=TTL1+TTL2+TTL3 and BFL=BFL1+BFL2+BFL3.

FIG. 2D shows schematically a cross section of a mobile device 280 (e.g. a smartphone) having an exterior front surface 282 and an exterior rear surface 284 including double folded Tele camera 250. The aperture of camera 250 is located at rear surface 284. Front surface 282 may e.g. include a screen (not visible). Mobile device 280 has a regular region 286 of thickness (“T”) and a bump region 288. The bump region has a bump length (“BL”) and a bump thickness T+B. Module region 272 of camera 250 is included in bump region 288. Shoulder region 274 is included in regular region 286. Optionally, in some embodiments, parts of shoulder region 274 may also be included in bump region 288.

Camera 250, which may be only partially included in bump region 288, allows for a relatively small camera bump region (i.e. a short BL).

To clarify, all camera modules and optical lens systems disclosed herein are beneficially for use in mobile devices such as smartphones, tablets etc.

FIGS. 3A-3D and FIGS. 4-7A illustrate optical lens systems disclosed herein. All lens systems shown in FIGS. 3A-3D and FIGS. 4-7A can be included in a double folded camera module such as 200 or 250 shown in FIGS. 2A-D. In all optical lens systems disclosed in the following, the optical height and width of lens element Li defines the optical lens systems’ aperture.

Table 1 summarizes values and ratios thereof of various features that are included in the lens systems 300, 320, 350, 400, 500, 600 and 700 shown in FIGS. 3A-3E and FIGS. 4-7A (HL1, WL1, DA, MHs, MHM, HS, HM, ALO, TTL1, BFL1, TTL2, BFL2, TTL3, TTL, BFL, EFL, EFL-G1, EFL-G2, SD, ALT, d5-6, fl, f6, Tl, MLM, LM, MHM, MHS, T-Gl, T-G2 are given in mm, HFOV given in degrees).

- “Type” specifies whether the optical lens system is a 1G or a 2G optical lens system.

- N specifies the number of lens elements. - DA is the aperture diameter. For the cut lenses 352, 402and 702, an effective aperture diameter is given. “Effective aperture diameter” means here a diameter of a circular (or axial symmetric) aperture, wherein the circular aperture has a same aperture area as the cut lens (which has a non axial-symmetric aperture). - EFL-G1 and EFL-G2 are the effective focal lengths of lens groups G1 and G2 respectively.

- The average lens thickness (“ALT”) measures the average thickness of all lens elements.

- The average gap thickness (“AGT”) measures the average thickness of all gaps between lens elements which are located on an object side of the mirror.

- ds-6 is the distance between Ls and Le. - Ti, T-Gl and T-G2 are the center thicknesses of Li, G1 and G2 respectively. For 1G optical lens systems, T-Gl = Teens, Teens being the thickness of a lens.

- In other examples, Hei may be in the range Hei = 4mm - 15mm.

- All other parameters not specifically defined here have their ordinary meaning as known in the art.

Table 1 FIG. 3A shows an embodiment of an optical lens system disclosed herein and numbered 300. Lens system 300 comprises a lens 302, an O-OPFE 304 (e.g. a prism or a mirror), an I- OPFE 306 (e.g. a prism or a mirror), an optical element 307 and an image sensor 308. System 300 is shown with ray tracing. As for all following optical lens systems, optical element 307 is optional and may be for example an infra-red (IR) filter, and/or a glass image sensor dust cover.

O-OPFE 304 and I-OPFE 306 are both oriented at an angle of 45 degrees with respect to the y-axis and the z-axis. As for all following optical lens systems, MHM and MHs of a camera module such as module 200 that may include optical system 300 are shown.

Lens 302 includes a plurality of N lens elements Li (wherein “i” is an integer between 1 and N). Here and for example, N=6. Lens 302 is divided in two lens groups, 302-G1 that includes Li - L2, and 302-G2 that includes L - Le. As for all following optical lens systems, the lens elements within each lens group do not move with respect to each other.

Li is the lens element closest to the object side and LN is the lens element closest to the image side, i.e. the side where the image sensor is located. This order holds for all lenses and lens elements disclosed herein. 302-G1 has an optical (lens) axis 312 and 302-G2 has an optical axis 314. Lens elements Li - L2 included in 302-G1 are axial-symmetric along OP1 312. Lens elements La - Le included in 302-G2 are axial-symmetric along OP2 314. Each lens element Li comprises a respective front surface S2M (the index “2i-l” being the number of the front surface) and a respective rear surface Sai (the index “2i” being the number of the rear surface), where “i” is an integer between 1 and N. This numbering convention is used throughout the description. Alternatively, as done throughout this description, lens surfaces are marked as “Sk”, with k running from 1 to 2N. The front surface and the rear surface can be in some cases aspherical. This is however not limiting.

As used herein the term "front surface" of each lens element refers to the surface of a lens element located closer to the entrance of the camera (camera object side) and the term "rear surface" refers to the surface of a lens element located closer to the image sensor (camera image side). Detailed optical data and surface data are given in Tables 2-3 for the example of the lens elements in FIG. 3A. The values provided for these examples are purely illustrative and according to other examples, other values can be used.

Surface types are defined in Table 2. The coefficients for the surfaces are defined in Table 3. The surface types are: a) Plano: flat surfaces, no curvature b) Q type 1 (QT1) surface sag formula: where {z, r} are the standard cylindrical polar coordinates, c is the paraxial curvature of the surface, k is the conic parameter, rnorm is generally one half of the surface’s clear aperture, and An are the polynomial coefficients shown in lens data tables. The Z axis is positive towards the image. Values for aperture radius are given as a clear aperture (or simply “aperture”) radius, i.e. DA/2. The reference wavelength is 555.0 nm. Units are in mm except for refraction index (“Index”) and Abbe #.

Table 2

Each lens element Li has a respective focal length ft, given in Table 2. The FOV is given as 5 half FOV (HFOV). The definitions for surface types, Z axis, DA values, reference wavelength, units, focal length and HFOV are valid for Tables 1-13.

In some examples, O-OPFE 304 is a mirror and O-OPFE 304’s dimensions are 3.1x3.63mm (x, y, in a top view on O-OPFE), and it is tilted by 45deg. Afterward it is Y- decentered by 0.845 mm toward L2, so that the center of the O-OPFE is not located at the 10 center of the lens . In some examples, I-OPFE 306 is a mirror and I-OPFE 306 s dimensions are 3.9x3.6mm (x, y, in a top view on I-OPFE), and it is tilted by 45deg. Afterward it is Y- decentered by 0.451 mm toward optical element 307.

Table 3

FIG. 3B shows another 2G optical lens system disclosed herein and numbered 320. Lens system 320 is identical to optical lens system 300, except that the second lens group 322-G2 is a cut lens obtained by cutting lens group 302-G2 as known in the art. The cutting is performed only at a bottom side 315 of 322-G2, while a top side 317 of 322-G2 is not cut. As shown in FIG. 3B, the cutting allows smaller HMM and MHs (see Table 1). Both HMM and MHs are reduced by the cutting by about 10%.

FIG. 3C shows yet another 2G optical lens system disclosed herein and numbered 350. Lens system 350 comprises a lens 352, an O-OPFE 354, an I-OPFE 356, an optical element 357 and an image sensor 358. Lens 352 is divided in two lens groups, 352-G1 that includes Li - L2 (“GI”), and 352-G2 that includes L - Le (“G2”).

O-OPFE 354 and I-OPFE 356 are both oriented at an angle of 45 degrees with respect to the y-axis and the z-axis.

The reduction in MHM (with respect to optical lens systems 300 and 320) is caused by the fact that because the extreme fields entering optical system 350 along a y-direction are reduced, so that the width of O-OPFE 354 can be reduced. Cutting a first lens group such as 302-G1 by X% will reduce MHM and MHs by about

0.5-X% - X%. For example, cutting a first lens group 20% will reduce MHM and MHs by about 10% - 20%.

Except for the lens apertures (DA/2, see Table 1), lens elements Li - Le included in optical lens system 350 have surface types and surface coefficients like lens elements Li - Le included in optical lens system 300, but in optical lens system 350 lens 352 is cut by 20%. 352-G1 and 352-G2 are cut along the z-axis and along the y-axis respectively. 352-G1 is cut at both sides 362 and 364. 352-G2 is also cut at both sides 366 and 368. Surface types of optical lens system 350 are defined in Table 4. The surface types are given for the non-cut lens, aperture radii (DA/2) of the lens elements included in the cut lens 352 are given by: 1. In non-cut direction (Lu) see values in Table 4.

2. In cut direction (Lwi): 80% of the value see Table 4 of the largest lens element of 352-G1 (Li) for lens elements included in 352-G1 and 352-G2 (Le) respectively.

Table 4

A cut lens includes one or more lens elements Li which are cut, i.e. which have Wu > Hu (see example FIG. 3E). Cutting a lens by X% may reduce a MHM and/or a MHs of a camera module 5 such as 200 or 250 that includes any of the optical lens systems disclosed herein by about 0.5-X% - X%. For example, a D-cut ratio may be 0% - 50%, meaning that Wu may be larger than HL; by 0% - 50%, i.e. Wu = HL; - 1.5-HLL In some examples, a first lens group located at an object side of an O-OPFE such as 352-G1 and a second lens group located at an image side of an O-OPFE such as 352-G2 may be cut differently, i.e. the first lens group may have a D- 10 cut ratio that is different than the D-cut ratio of the second lens group.

FIG. 3D shows 2G optical lens system 350 in a perspective view. The cut lens sides 362 and 364 of 352-G1 are visible as well as the un-cut sides 363 and 365. Also the cut lens sides 366 and 368 of 352-G2 are visible as well as the uncut sides 367 and 369 of 352-G2. FIG. 3E shows element Li included in 352-G1 of 2G optical lens system 350 in a top view. Li is cut by 20%, i.e. its optical width WLI is 20% larger than its optical height HLI. AS LI defines the aperture of lens 352, this means that also the aperture diameter DA changed accordingly, so that the aperture is not axial symmetric. For cut lenses, DA is an effective aperture diameter as defined above.

Because of the D cut, a width of the aperture (“WL”) of lens 352 may be larger than a height “HL”, as shown in FIG. 3E. HLI is not measured along the z-axis, as e.g. for an optical height of lens elements included in 352-G2 or the lens elements of lens 104, see FIG. 1A, but along the y-axis. Therefore, HLI is not limited by MHM, i.e. a lens such as lens 352 can support embodiments satisfying HLI > MHs, i.e. an aperture height (measured along the z-axis) which is larger than the module shoulder, opposite to known folded camera 100. This is beneficial in terms of the image quality of a camera that includes the optical systems disclosed herein, as it can overcome the geometrical limitation (i.e. HL < MHs) posed on lenses included in a module shoulder, as e.g. shown for the known folded camera 100 shown in FIG. 1A. The large aperture height allows for a larger effective DA, leading to a lower f/#, which is beneficial as it allows for more light entering the camera in a given time interval. The definitions and explanations given in FIG. 3E for optical lens system 350 are valid also for all other optical lens systems disclosed herein.

FIG. 4 shows another 2G optical lens system numbered 400. Lens system 400 comprises a lens 402, an O-OPFE 404 (e.g. a prism or a mirror), an I-OPFE 406 (e.g. a prism or a mirror), an optical element 407 and an image sensor 408. O-OPFE 404 and I-OPFE 406 are both oriented at an angle of 45 degrees with respect to the y-axis and the z-axis. Lens 402 is divided into G1 (including Li and L2) and G2 (including L - Le). In some examples, 402-G1 and/or 402-G2 may be cut lenses as see examples above. Detailed optical data and surface data for optical lens system 400 are given in Tables 5-6. O-OPFE 404 may be a mirror with dimensions 7.4mmx7.82mm (measured within the O-OPFE plane). I-OPFE 406 may be a mirror with dimensions 8.4mmx7.86mm (measured within the I-OPFE plane). Thicknesses relative to the OPFEs are with respect to the optical axis. In some examples, lens 402 may be cut as see FIG. 3B, so that O-OPFE 404 and I-OPFE 406 determine MHM and MHs, as shown for MHM-CUI and MHs-cut. For such an example, MHM-CU1= 8.85mm and MHs-cut = 6.35mm (as shown).

Table 5

Table 6

Table 6 (Cont.) FIG. 5 shows a “1 -group” (or “1G”) optical lens system numbered 500 comprising a lens 502 with N=4 lens elements, an O-OPFE 504, an I-OPFE 506, an optical element 507 and an image sensor 508. Lens 502 is not divided in two lens groups, but all 4 lens elements are located at an object side of O-OPFE 504.

Detailed optical data and surface data for optical lens system 500 are given in Tables 7-8. Both O-OPFE 504 and I-OPFE 506 may be mirrors. Dimensions of O-OPFE 504 and I-

OPFE 506 are 5.0mmx5.2mm (measured within the OPFE planes). Thicknesses relative to the mirror are with respect to the optical axis. O-OPFE 504 and I-OPFE 506 are tilted by 45 degrees with respect to OP1 and OP2.

In some examples of 1G optical lens systems such as 500, 600 and 700, a lens may be a cut lens as see examples above. By cutting along the z-axis, a lower MHM and MHs may be achieved by reducing an O-OPFE’s and a I-OPFE’s size. By cutting a lens by X% will reduce MHM and MHs by about 0.5-X% - X%. For example, cutting a lens by 20% will reduce MHM and MHs by about 10% - 20%.

5

Table 7

15

Table 8

Table 8 (Cont.)

FIG. 6 shows another 1G optical lens system numbered 600 comprising a lens 602 with N=4 lens elements, an O-OPFE 604, an I-OPFE 606, an optical element 607 and an image sensor 608. All 4 lens elements of lens 602 are located at an object side of O-OPFE 604. Detailed optical data and surface data for optical lens system 600 are given in Tables 9-10. Both O-OPFE 6504 and I-OPFE 606 may be mirrors. Dimensions of O-OPFE 604 are 8.0mmx6.1mm (measured within the O-OPFE plane). Dimensions of I-OPFE 606 are 9.6mmx7.9mm (measured within the I-OPFE plane). Thicknesses relative to the OPFEs are with respect to the optical axis. O-OPFE 604 is tilted by a=43 degrees with respect to the y- axis. I-OPFE 606 is tilted by p=47 degrees with respect to the y-axis.

able 9

Table 10

5

Table 10 (Cont.)

FIG. 7A shows yet another 1G optical lens system numbered 700 comprising a lens 702 with N=4 lens elements, an O-OPFE 704, an I-OPFE 706, an optical element 707 and an image sensor 708. All 4 lens elements are located at an object side of O-OPFE 704.

Detailed optical data and surface data for optical lens system 700 are given in Tables 11-12. O-OPFE 704 may be a mirror and I-OPFE 706 may be a prism. Dimensions of O-OPFE 704 are 6.2mmx4.64mm (measured within the O-OPFE plane). Dimensions of I-OPFE 706 are 6.7mmx9.16mm (measured within the I-OPFE plane). O-OPFE 704 and I-OPFE 706 are tilted by 45 degrees with respect to the y-axis. O-OPFE 704 is a mirror, I-OPFE 706 is a prism.

Prism 706 includes an object-sided bottom stray light prevention mechanism 732, an object-sided top stray light prevention mechanism 734, an image-sided bottom stray light prevention mechanism 722 and an image-sided top stray light prevention mechanism 724.

able 11

Table 12

Table 12 (cont.)

FIG. 7B shows prism 706 in a side view. FIG. 7C shows prism 706 in a perspective view.. Object-sided bottom stray light prevention mechanism 732 and object-sided top stray light prevention mechanism 734 are stray light prevention masks. This means that no light is entering prism 706 where stray mask 732 and stray mask 734 are located, but light enters only in optically active are 736. Image-sided bottom stray light prevention mechanism 722 and imagesided top stray light prevention mechanism 724 are geometrical stray light prevention mechanisms that are referred to in the following as “stray light prevention shelves”.

Prism 706 has a prism height (”Hp”) and an optical (or optically active) prism height (”Hp-o”) measured along the z-axis, a prism length (”Lp”) measured along the y-axis and a prism width (”Wp”) measured along the x-axis. Bottom stray light prevention shelve 722 and top stray light prevention shelve 724 have a length (”LBS” and ”LTS” for a length of the “bottom shelve” and “top shelve” respectively) and a height (”HBS” and ”HTS” respectively). Bottom stray light prevention mask 732 and top stray light prevention mask 734 have a height (”HBM” and "HTM" for a height of the “bottom mask” and “top mask” respectively. Values and ranges are given in Table 13 in mm.

The stray light prevention mechanisms are beneficial because they prevent stray light from reaching an image sensor such as image sensor 708. Stray light is undesired light emitted or reflected from an object in a scene which enters a camera’s aperture and reaches an image sensor at a light path that is different from a planned (or desired) light path. A planned light path is described as follows:

1. Light is emitted or reflected by an object in a scene. 2. Light enters the camera’s aperture and passes once all surfaces of a lens (for 1G optical lens systems) or a G1 of a lens (for 2G optical lens systems).

3. For examples where O-OPFE is a mirror, light is reflected once. For examples where O-OPFE is a prism, light passes once an object-sided surface of an O-OPFE, is reflected once as shown for the optical lens systems disclosed herein, and then passes once an image-sided surface of an O-OPFE.

4. For 2G optical lens systems, light passes once all surfaces of a G2 of a lens.

5. For examples where I-OPFE is a mirror, light is reflected once. For examples where I- OPFE is a prism, light passes once an object-sided surface of an I-OPFE, is reflected once as shown for the optical lens systems disclosed herein, and then passes once an image-sided surface of an I-OPFE.

6. Light impinges on an image sensor.

Light that reaches an image sensor on any light path other than the planned light path described above is considered undesired and referred to as stray light.

Table 13

FIG. 8A shows schematically a method for focusing (or “autofocusing” or “AF”) in an optical lens systems disclosed herein.

Focusing of 1G optical system

Lens 802 and O-OPFE 804 are moved together linearly along the y-axis relative to I- OPFE 806 and image sensor 808, which do not move. Box 812 indicates the components moving for performing AF, arrow 814 indicates the direction of movement for performing AF. An actuator as known in the art, e.g. a voice coil motor (VCM) or a stepper motor, may be used for actuating this movement as well as all other movements described in FIGS. 8A-C.

In addition, a 1G optical lens system can perform focusing and OIS like a regular (or “vertical” or “non-folded”) camera such as Wide camera 130. Specifically, a 1G optical lens system can be focused by moving only a lens such as lens 802 along an axis parallel to the z- axis with respect to all other camera components, i.e. lens 802 is moved along the z-axis with respect to O-OPFE 804, 1-OPFE 806 and image sensor 808. For performing OIS along a first OIS axis, only lens 802 can be moved along an axis parallel to the y-axis with respect to all other camera components. For performing OIS along a second OIS axis, lens 802 can be moved along an axis perpendicular to both the y-axis and the z-axis with respect to all other camera components.

Focusing of 2G optical system

A first lens group such as e.g. lens group 302-G1, an O-OPFE such as O-OPFE 304 and a second lens group such as lens group 302-G2 are moved together along the y-direction. An I-OPFE such as I-OPFE 306 and an image sensor such as image sensor 308 do not move.

FIG. 8B shows schematically a method for performing optical image stabilization (OIS) in a first OIS direction for optical lens systems disclosed herein.

OIS in a first direction in 1G optical lens systems

Lens 802, O-OPFE 804 and I-OPFE 806 are moved together linearly along the y-axis relative to image sensor 808, which does not move. Box 816 indicates the components moving for performing OIS in a first OIS direction, arrow 818 indicates the direction of movement for performing OIS in a first OIS direction.

OIS in a first direction in 2G optical lens systems

A first lens group such as 302-G1, an O-OPFE such as O-OPFE 304, a second lens group such as 302-G2 and an I-OPFE such as I-OPFE 306 are moved together along the y- direction. An image sensor such as image sensor 308 does not move. In other 2G optical lens systems, only a first lens group such as 302-G1, an O-OPFE such as O-OPFE 304 and a second lens group such as 302-G2 are moved relative to an I-OPFE such as I-OPFE 306 and relative to an image sensor such as image sensor 308.

FIG. 8C shows schematically a method disclosed herein for performing OIS in a second OIS direction for optical lens systems disclosed herein.

OIS in a second direction in 1G optical lens systems

Lens 802, O-OPFE 804 and I-OPFE 806 are moved together linearly perpendicular to the y-z coordinate system shown relative to image sensor 808, which does not move. Box 816 indicates the components moving for performing OIS in a second OIS direction, arrows 822 indicate the direction of movement for performing OIS in a second OIS direction. Arrows 822 point in directions which are perpendicular to the y-z coordinate system shown.

OIS in a second direction in 2G optical lens systems

A first lens group such as 302-G1, an O-OPFE such as O-OPFE 304, a second lens group such as 302-G2 and an I-OPFE such as I-OPFE 306 are moved linearly perpendicular to the y- z coordinate system shown relative to an image sensor such as image sensor 308, which does not move. In other 2G optical lens systems, only a first lens group such as 302-G1, an O-OPFE such as O-OPFE 304 and a second lens group such as 302-G2 are moved relative to an I-OPFE such as I-OPFE 306 and relative to an image sensor such as image sensor 308.

It is appreciated that certain features of the presently disclosed subject matter, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the presently disclosed subject matter, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

Unless otherwise stated, the use of the expression “and/or” between the last two members of a list of options for selection indicates that a selection of one or more of the listed options is appropriate and may be made.

It should be understood that where the claims or specification refer to "a" or "an" element, such reference is not to be construed as there being only one of that element.

Furthermore, for the sake of clarity the term "substantially" is used herein to imply the possibility of variations in values within an acceptable range. According to one example, the term "substantially" used herein should be interpreted to imply possible variation of up to 5% over or under any specified value. According to another example, the term "substantially" used herein should be interpreted to imply possible variation of up to 2.5% over or under any specified value. According to a further example, the term "substantially" used herein should be interpreted to imply possible variation of up to 1% over or under any specified value.

All patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present disclosure.