Patent Description:
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.

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:.

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

<FIG> illustrates a known dual-camera <NUM> that comprises folded Tele camera <NUM> and a (vertical or upright) Wide camera <NUM> that includes a Wide lens <NUM> and a Wide image sensor <NUM>. Lens <NUM> is included in a lens barrel <NUM>. Wide camera <NUM> has an OP <NUM> which is substantially parallel with OP <NUM>.

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

<FIG> shows a known cut lens element <NUM> in a cross-sectional view. Lens element <NUM> may define an aperture of an optical lens system including lens element <NUM>. Lens element <NUM> is cut by <NUM>%, i.e. its optical width WL is <NUM>% 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>), 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 <NUM> 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 <NUM> incorporates a relatively small image sensor having a SD of about <NUM>-<NUM>, and has a relatively small HL of about <NUM>-<NUM>, resulting in a relatively large f/# of about <NUM>-<NUM> and in a relatively small ratio of HL/HM. HM is the height of a camera module including a double folded camera such as <NUM>, HM may be about <NUM>-<NUM>. HM is connected to the minimum module height ("MHM", see <FIG>) by HM = MHM+ height penalty ("penalty"), the penalty being about <NUM> - <NUM>.

A folded Tele camera comprising an optical path folding element, a lens including two lens groups (<NUM> lens and <NUM> lenses) and an image sensor is disclosed in <CIT> and a folded Tele camera comprising an optical path folding element, a lens with <NUM> elements including two lens groups (<NUM> lens and <NUM> lenses) and an image sensor is disclosed in <CIT>.

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.

In various exemplary embodiments, there are provided camera modules, comprising: a lens with N = <NUM> lens elements Li divided into a first lens group (G1) and a second lens group (G2) and having an effective focal length EFL, an aperture diameter DA, a f-number f/#, a total track length TTL and a back focal length BFL, wherein each lens element has a respective focal length fi and wherein a first lens element L<NUM> 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 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 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 <NUM><EFL<<NUM>, 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 > <NUM>. and wherein the camera module (<NUM>) has a minimum camera module length MLM and wherein EFL > <NUM>.

In some examples, HL/MHS > <NUM>. In some examples, HL/MHS > <NUM>. In some examples, HL/MHS > <NUM>.

In some examples, EFL > <NUM>·MLM. In some examples, EFL > <NUM>·MLM.

In some examples, SD/EFL > <NUM>. In some examples, SD/EFL > <NUM>. In some examples, SD/EFL > <NUM>.

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

In some examples, BFL/EFL > <NUM>. In some examples, BFL/TTL > <NUM>.

In some examples, <NUM> < EFL < <NUM>. In some examples, <NUM> < EFL < <NUM>.

In some examples, <NUM> < DA < <NUM> and <NUM> < f/# < <NUM>. In some examples, <NUM> <DA < <NUM> and <NUM> < f/# < <NUM>.

In some examples, G1, the O-OPFE and G2 are movable together along OP2 relative to I-OPFE and the image sensor for focusing.

In some examples, G1, 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, G1, 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, G1, 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, G1, 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, <NUM> < HS < <NUM> and <NUM> < HM < <NUM>. In some examples, <NUM> < HS < <NUM> and <NUM> < HM < <NUM>.

In some examples, HS/HM < <NUM>. In some examples, HS/HM < <NUM>.

In some examples, a ratio between an average lens thickness (ALT) of all lens elements L<NUM> -LN and TTL fulfills ALT/TTL < <NUM>. In some examples, a ratio of the thickness of L1 (T1) and ALT fulfills T1/ALT > <NUM>.

In some examples, a distance d<NUM>-<NUM> between L<NUM> and L<NUM> and ALT fulfills d<NUM>-<NUM>/ALT > <NUM>.

In some examples, L<NUM> is made of glass.

In some examples, ratio between f1 of L<NUM> and EFL fulfills f1/EFL < <NUM>.

In some examples, a ratio between |f6| of L<NUM> and EFL fulfills |f6|/EFL > <NUM>.

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

In some examples, G1 has a thickness T-G1 and T-G1/TTL < <NUM>.

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

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

In some examples, G1 is cut by <NUM>% and HM is reduced by ><NUM>% 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 <NUM>% and has a cut lens diameter and HM is reduced by ><NUM>% 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, OP1 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 = <NUM> lens elements Li having a lens thickness TLens, 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 L<NUM> 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 <NUM><EFL<<NUM>, wherein a ratio between a lens thickness TLens and the TTL, TLens/TTL < <NUM>.

In some examples, TLen/TTL < <NUM>. In some examples, TLens/TTL < <NUM>.

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 -<NUM>.

According to the invention, HL><NUM>·MHS. In some examples, HL>MHS.

According to the invention, EFL > <NUM>·MLM. In some examples, EFL > <NUM>·MLM. In some examples, EFL > <NUM>M.

In some examples, TTL > <NUM>·MLM. In some examples, TTL > <NUM>·MLM. In some examples, TTL > <NUM>·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 OP1 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, L<NUM> is made of glass and has a refractive index n of n><NUM>.

In some examples, a sequence of the power of the lens elements L<NUM> - L<NUM> is plus-minus-plus-plus. In some examples, a sequence of the power of the lens elements L<NUM> - L<NUM> is plus-minus-plus-minus. In some examples, a sequence of the power of the lens elements L<NUM> - L<NUM> is plus-minus-minus-plus.

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.

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> shows schematically an embodiment of a "<NUM>-group" (or "<NUM>") double folded Tele camera module disclosed herein and numbered <NUM>. Camera module <NUM> comprises a lens <NUM> with a plurality of N lens elements (here and for example N=<NUM>) numbered L<NUM> - LN, with L<NUM> being oriented towards an object side. Camera module <NUM> further comprises an O-OPFE <NUM> for folding a first optical path OP1 <NUM> to a second optical path OP2 <NUM>, an I-OPFE <NUM> for folding OP2 to a third optical path OP3 <NUM> and an image sensor <NUM>. The camera elements may be included in a module housing <NUM>, as shown. In camera <NUM>, OP1 <NUM> is substantially parallel with the z-axis, and OP2 <NUM> is substantially parallel with the y-axis and OP3 <NUM> is substantially parallel with the z-axis. O-OPFE <NUM> and I-OPFE <NUM> form an angle of <NUM> degrees with both the y-axis and the z-axis. Image sensor <NUM> 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 <NUM> may not be a double folded Tele camera module, but a (single) folded Tele camera module. it may not have an OP3 and it may not include an I-OPFE such as I-OPFE <NUM>. In these other examples, OP1 may be oriented perpendicular to OP2 (as shown) and an image sensor such as image sensor <NUM> 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 <NUM> may be a double folded Tele camera module, but OP3 may be perpendicular to OP1 (not parallel, as shown). In these yet other examples, OP1 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 <NUM> may be oriented in a plane parallel to the shown y-z-coordinate system.

Lens <NUM> is divided into a first lens group ("G1") and a second lens group ("G2"),marked <NUM>-G1 and <NUM>-G2. G1 is located at an object side of O-OPFE <NUM> and G2 is located at an image side of O-OPFE <NUM> and at an object side of I-OPFE <NUM>.

Camera module <NUM> is divided into a first, "module" region including <NUM>-G1 and O-OPFE <NUM> that has a module region height HM and a minimum module region length MRLM (as shown), and a second, "shoulder" region including I-OPFE <NUM> and the image sensor <NUM> that has a shoulder region height Hs < HM and a shoulder region length LS. All heights are measured along OP1 <NUM>, all lengths are measured along OP2 <NUM>.

The optical height and width of lens element L<NUM> may define the aperture (having a diameter DA) of camera <NUM>, so that the optical height and the optical width of lens element L<NUM> represent also the aperture height and aperture width respectively. The height of lens element L<NUM>, HL1, 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 <NUM>):.

The TTL of camera module <NUM> is divided into three parts, TTL1 - TTL3, as shown. The BFL of camera module <NUM> is divided into two parts, BFL1 and BFL2. A first part TTL1 is parallel with OP1 <NUM>, a second part TTL2 and a first part BFL1 are parallel with OP2 <NUM>, a third part TTL3 and a second part BFL2 are parallel with OP3 <NUM>. TTL and BFL are obtained by TTL=TTL1+TTL2+TTL3 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.

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

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

<FIG> shows schematically an embodiment of a "<NUM>-group" (or "<NUM>") double folded Tele camera module disclosed herein and numbered <NUM>. Camera module <NUM> comprises a lens <NUM> with a plurality of N lens elements (here and for example N=<NUM>) numbered L<NUM> - LN, with L<NUM> being oriented towards an object side. Camera module <NUM> further comprises an O-OPFE <NUM> for folding OP1 <NUM> to OP2 <NUM>, an I-OPFE <NUM> for folding OP2 to OP3 <NUM> and an image sensor <NUM>. The camera elements may be included in a module housing <NUM>. In camera <NUM>, OP1 <NUM> is substantially parallel with the z-axis, and OP2 <NUM> is substantially parallel with the y-axis and OP3 <NUM> is substantially parallel with the z-axis. O-OPFE <NUM> and I-OPFE <NUM> may or may not form an angle of <NUM> degrees with both the y-axis and the z-axis. Lens <NUM> in its entirety is located at an object side of O-OPFE <NUM>. Image sensor <NUM> is oriented in a plane perpendicular to the z-axis in the shown coordinate system.

The optical height and width of lens element L<NUM> may define the aperture of camera <NUM>. The height of lens element L<NUM>, HL1, 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 <NUM>):.

Camera module <NUM> is divided into a module region having a module region height HM and including lens <NUM> and O-OPFE <NUM>, and a shoulder region having a shoulder region height HS< HM and including I-OPFE <NUM> and image sensor <NUM>.

The TTL and the BFL of camera module <NUM> 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> shows schematically a cross section of a mobile device <NUM> (e.g. a smartphone) having an exterior front surface <NUM> and an exterior rear surface <NUM> including double folded Tele camera <NUM>. The aperture of camera <NUM> is located at rear surface <NUM>. Front surface <NUM> may e.g. include a screen (not visible). Mobile device <NUM> has a regular region <NUM> of thickness ("T") and a bump region <NUM>. The bump region has a bump length ("BL") and a bump thickness T+B. Module region <NUM> of camera <NUM> is included in bump region <NUM>. Shoulder region <NUM> is included in regular region <NUM>. Optionally, in some embodiments, parts of shoulder region <NUM> may also be included in bump region <NUM>.

Camera <NUM>, which may be only partially included in bump region <NUM>, 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..

<FIG> and <FIG> illustrate optical lens systems disclosed herein. All lens systems shown in <FIG> and <FIG> can be included in a double folded camera module such as <NUM> or <NUM> shown in <FIG>. In all optical lens systems disclosed in the following, the optical height and width of lens element L<NUM> defines the optical lens systems' aperture.

Table <NUM> summarizes values and ratios thereof of various features that are included in the lens systems <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> shown in <FIG> and <FIG> (HL<NUM>, WL<NUM>, DA, MHS, MHM, HS, HM, ΔLO, TTL1, BFL1, TTL2, BFL2, TTL3, TTL, BFL, EFL, EFL-G1, EFL-G2, SD, ALT, d5-<NUM>, f1, f6, T1, MLM, LM, MHM, MHS, T-G1, T-G2 are given in mm, HFOV given in degrees).

- "Type" specifies whether the optical lens system is a <NUM> or a <NUM> optical lens system. - N specifies the number of lens elements. - DA is the aperture diameter. For the cut lenses <NUM>, <NUM>and <NUM>, 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. - d<NUM>-<NUM> is the distance between L<NUM> and L<NUM>. - T<NUM>, T-G1 and T-G2 are the center thicknesses of L<NUM>, G1 and G2 respectively. For <NUM> optical lens systems, T-G1 = TLens, TLens being the thickness of a lens. - In other examples, HL1 may be in the range HL1 = <NUM> - <NUM>. - All other parameters not specifically defined here have their ordinary meaning as known in the art.

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

O-OPFE <NUM> and I-OPFE <NUM> are both oriented at an angle of <NUM> 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 <NUM> that may include optical system <NUM> are shown.

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

L<NUM> 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. <NUM>-G1 has an optical (lens) axis <NUM> and <NUM>-G2 has an optical axis <NUM>. Lens elements L<NUM> - L<NUM> included in <NUM>-G1 are axial-symmetric along OP1 <NUM>. Lens elements L<NUM> - L<NUM> included in <NUM>-G2 are axial-symmetric along OP2 <NUM>. Each lens element Li comprises a respective front surface S2i-<NUM> (the index "2i-<NUM>" being the number of the front surface) and a respective rear surface S2i (the index "2i" being the number of the rear surface), where "i" is an integer between <NUM> 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 <NUM> 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 <NUM>-<NUM> for the example of the lens elements in <FIG>. 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 <NUM>. The coefficients for the surfaces are defined in Table <NUM>. The surface types are:.

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/<NUM>. The reference wavelength is <NUM>. Units are in mm except for refraction index ("Index") and Abbe #.

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

In some examples, O-OPFE <NUM> is a mirror and O-OPFE <NUM>'s dimensions are <NUM>. <NUM> (x, y, in a top view on O-OPFE), and it is tilted by 45deg. Afterward it is Y-decentered by <NUM> toward L2, so that the center of the O-OPFE is not located at the center of the lens.

In some examples, I-OPFE <NUM> is a mirror and I-OPFE <NUM>'s dimensions are <NUM>. <NUM> (x, y, in a top view on I-OPFE), and it is tilted by 45deg. Afterward it is Y-decentered by <NUM> toward optical element <NUM>.

<FIG> shows another <NUM> optical lens system disclosed herein and numbered <NUM>. Lens system <NUM> is identical to optical lens system <NUM>, except that the second lens group <NUM>-G2 is a cut lens obtained by cutting lens group <NUM>-G2 as known in the art. The cutting is performed only at a bottom side <NUM> of <NUM>-G2, while a top side <NUM> of <NUM>-G2 is not cut. As shown in <FIG>, the cutting allows smaller MHM and MHs (see Table <NUM>). Both MHM and MHS are reduced by the cutting by about <NUM>%.

<FIG> shows yet another <NUM> optical lens system disclosed herein and numbered <NUM>. Lens system <NUM> comprises a lens <NUM>, an O-OPFE <NUM>, an I-OPFE <NUM>, an optical element <NUM> and an image sensor <NUM>. Lens <NUM> is divided in two lens groups, <NUM>-G1 that includes L<NUM> - L<NUM> ("G1"), and <NUM>-G2 that includes L<NUM> - L<NUM> ("G2").

O-OPFE <NUM> and I-OPFE <NUM> are both oriented at an angle of <NUM> degrees with respect to the y-axis and the z-axis.

The reduction in MHM (with respect to optical lens systems <NUM> and <NUM>) is caused by the fact that because the extreme fields entering optical system <NUM> along a y-direction are reduced, so that the width of O-OPFE <NUM> can be reduced.

Cutting a first lens group such as <NUM>-G1 by X% will reduce MHM and MHs by about <NUM>·X% - X%. For example, cutting a first lens group <NUM>% will reduce MHM and MHs by about <NUM>% - <NUM>%.

Except for the lens apertures (DA/<NUM>, see Table <NUM>), lens elements L<NUM> - L<NUM> included in optical lens system <NUM> have surface types and surface coefficients like lens elements L<NUM> - L<NUM> included in optical lens system <NUM>, but in optical lens system <NUM> lens <NUM> is cut by <NUM>%. <NUM>-G1 and <NUM>-G2 are cut along the z-axis and along the y-axis respectively. <NUM>-G1 is cut at both sides <NUM> and <NUM>. <NUM>-G2 is also cut at both sides <NUM> and <NUM>. Surface types of optical lens system <NUM> are defined in Table <NUM>. The surface types are given for the non-cut lens, aperture radii (DA/<NUM>) of the lens elements included in the cut lens <NUM> are given by:.

A cut lens includes one or more lens elements Li which are cut, i.e. which have WLi > HLi (see example <FIG>). Cutting a lens by X% may reduce a MHM and/or a MHS of a camera module such as <NUM> or <NUM> that includes any of the optical lens systems disclosed herein by about <NUM>·X% - X%. For example, a D-cut ratio may be <NUM>% - <NUM>%, meaning that WLi may be larger than HLi by <NUM>% - <NUM>%, i.e. WLi = HLi - <NUM>·HLi. In some examples, a first lens group located at an object side of an O-OPFE such as <NUM>-G1 and a second lens group located at an image side of an O-OPFE such as <NUM>-G2 may be cut differently, i.e. the first lens group may have a D-cut ratio that is different than the D-cut ratio of the second lens group.

<FIG> shows <NUM> optical lens system <NUM> in a perspective view. The cut lens sides <NUM> and <NUM> of <NUM>-G1 are visible as well as the un-cut sides <NUM> and <NUM>. Also the cut lens sides <NUM> and <NUM> of <NUM>-G2 are visible as well as the uncut sides <NUM> and <NUM> of <NUM>-G2.

<FIG> shows element L<NUM> included in <NUM>-G1 of <NUM> optical lens system <NUM> in a top view. L<NUM> is cut by <NUM>%, i.e. its optical width WL1 is <NUM>% larger than its optical height HL1. As L<NUM> defines the aperture of lens <NUM>, 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 <NUM> may be larger than a height "HL", as shown in <FIG>. HL1 is not measured along the z-axis, as e.g. for an optical height of lens elements included in <NUM>-G2 or the lens elements of lens <NUM>, see <FIG>, but along the y-axis. Therefore, HL1 is not limited by MHM, i.e. a lens such as lens <NUM> can support embodiments satisfying HL1 > MHS, i.e. an aperture height (measured along the z-axis) which is larger than the module shoulder, opposite to known folded camera <NUM>. 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 <NUM> shown in <FIG>. 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> for optical lens system <NUM> are valid also for all other optical lens systems disclosed herein.

<FIG> shows another <NUM> optical lens system numbered <NUM>. Lens system <NUM> comprises a lens <NUM>, an O-OPFE <NUM> (e.g. a prism or a mirror), an I-OPFE <NUM> (e.g. a prism or a mirror), an optical element <NUM> and an image sensor <NUM>. O-OPFE <NUM> and I-OPFE <NUM> are both oriented at an angle of <NUM> degrees with respect to the y-axis and the z-axis. Lens <NUM> is divided into G1 (including L<NUM> and L<NUM>) and G2 (including L<NUM> - L<NUM>). In some examples, <NUM>-G1 and/or <NUM>-G2 may be cut lenses as see examples above. Detailed optical data and surface data for optical lens system <NUM> are given in Tables <NUM>-<NUM>. O-OPFE <NUM> may be a mirror with dimensions <NUM>. <NUM> (measured within the O-OPFE plane). I-OPFE <NUM> may be a mirror with dimensions <NUM>. <NUM> (measured within the I-OPFE plane). Thicknesses relative to the OPFEs are with respect to the optical axis. In some examples, lens <NUM> may be cut as see <FIG>, so that O-OPFE <NUM> and I-OPFE <NUM> determine MHM and MHS, as shown for MHM-cut and MHS-cut. For such an example, MHM-cut= <NUM> and MHS-cut = <NUM> (as shown).

<FIG> shows an example of a lens with <NUM> elements which is not covered by the scope of the claims and which shows a "<NUM>-group" (or "<NUM>") optical lens system numbered <NUM> comprising a lens <NUM> with N=<NUM> lens elements, an O-OPFE <NUM>, an I-OPFE <NUM>, an optical element <NUM> and an image sensor <NUM>. Lens <NUM> is not divided in two lens groups, but all <NUM> lens elements are located at an object side of O-OPFE <NUM>.

Detailed optical data and surface data for optical lens system <NUM> are given in Tables <NUM>-<NUM>. Both O-OPFE <NUM> and I-OPFE <NUM> may be mirrors. Dimensions of O-OPFE <NUM> and I-OPFE <NUM> are <NUM>. <NUM> (measured within the OPFE planes). Thicknesses relative to the mirror are with respect to the optical axis. O-OPFE <NUM> and I-OPFE <NUM> are tilted by <NUM> degrees with respect to OP1 and OP2.

In some examples of <NUM> optical lens systems such as <NUM>, <NUM> and <NUM>, 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 <NUM>·X% - X%. For example, cutting a lens by <NUM>% will reduce MHM.

<FIG> shows an example of a lens with <NUM> elements which is not covered by the scope of the claims and which shows another <NUM> optical lens system numbered <NUM> comprising a lens <NUM> with N=<NUM> lens elements, an O-OPFE <NUM>, an I-OPFE <NUM>, an optical element <NUM> and an image sensor <NUM>. All <NUM> lens elements of lens <NUM> are located at an object side of O-OPFE <NUM>. Detailed optical data and surface data for optical lens system <NUM> are given in Tables <NUM>-<NUM>. Both O-OPFE <NUM> and I-OPFE <NUM> may be mirrors. Dimensions of O-OPFE <NUM> are <NUM>. <NUM> (measured within the O-OPFE plane). Dimensions of I-OPFE <NUM> are <NUM>. <NUM> (measured within the I-OPFE plane). Thicknesses relative to the OPFEs are.

with respect to the optical axis. O-OPFE <NUM> is tilted by α=<NUM> degrees with respect to the y-axis. I-OPFE <NUM> is tilted by β=<NUM> degrees with respect to the y-axis.

<FIG> shows an example of a lens with <NUM> elements which is not covered by the scope of the claims and which shows yet another <NUM> optical lens system numbered <NUM> comprising a lens <NUM> with N=<NUM> lens elements, an O-OPFE <NUM>, an I-OPFE <NUM>, an optical element <NUM> and an image sensor <NUM>. All <NUM> lens elements are located at an object side of O-OPFE <NUM>.

Detailed optical data and surface data for optical lens system <NUM> are given in Tables <NUM>-<NUM>. O-OPFE <NUM> may be a mirror and I-OPFE <NUM> may be a prism. Dimensions of O-OPFE <NUM> are <NUM>. <NUM> (measured within the O-OPFE plane). Dimensions of I-OPFE <NUM> are <NUM>. <NUM> (measured within the I-OPFE plane). O-OPFE <NUM> and I-OPFE <NUM> are tilted by <NUM> degrees with respect to the y-axis. O-OPFE <NUM> is a mirror, I-OPFE <NUM> is a prism.

Prism <NUM> includes an object-sided bottom stray light prevention mechanism <NUM>, an object-sided top stray light prevention mechanism <NUM>, an image-sided bottom stray light prevention mechanism <NUM> and an image-sided top stray light prevention mechanism <NUM>.

<FIG> shows prism <NUM> in a side view. <FIG> shows prism <NUM> in a perspective view. Object-sided bottom stray light prevention mechanism <NUM> and object-sided top stray light prevention mechanism <NUM> are stray light prevention masks. This means that no light is entering prism <NUM> where stray mask <NUM> and stray mask <NUM> are located, but light enters only in optically active are <NUM>. Image-sided bottom stray light prevention mechanism <NUM> and image-sided top stray light prevention mechanism <NUM> are geometrical stray light prevention mechanisms that are referred to in the following as "stray light prevention shelves".

Prism <NUM> 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 <NUM> and top stray light prevention shelve <NUM> 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 <NUM> and top stray light prevention mask <NUM> have a height ("HBM" and "HTM" for a height of the "bottom mask" and "top mask" respectively. Values and ranges are given in Table <NUM> in mm.

The stray light prevention mechanisms are beneficial because they prevent stray light from reaching an image sensor such as image sensor <NUM>. 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:.

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.

<FIG> shows schematically a method for focusing (or "autofocusing" or "AF") in an optical lens systems disclosed herein.

Lens <NUM> and O-OPFE <NUM> are moved together linearly along the y-axis relative to I-OPFE <NUM> and image sensor <NUM>, which do not move. Box <NUM> indicates the components moving for performing AF, arrow <NUM> 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 <FIG>.

In addition, a <NUM> optical lens system can perform focusing and OIS like a regular (or "vertical" or "non-folded") camera such as Wide camera <NUM>. Specifically, a <NUM> optical lens system can be focused by moving only a lens such as lens <NUM> along an axis parallel to the z-axis with respect to all other camera components, i.e. lens <NUM> is moved along the z-axis with respect to O-OPFE <NUM>, I-OPFE <NUM> and image sensor <NUM>. For performing OIS along a first OIS axis, only lens <NUM> 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 <NUM> can be moved along an axis perpendicular to both the y-axis and the z-axis with respect to all other camera components.

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

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

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

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

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

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

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

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.

Claim 1:
A camera module (<NUM>), comprising:
a lens (<NUM>) with N = <NUM> lens elements Li divided into a first lens group (G1) (<NUM>-G1) and a second lens group (G2) (<NUM>-G2) and having an effective focal length EFL, an aperture diameter DA, a f-number f/#, a total track length TTL and a back focal length BFL, wherein each lens element has a respective focal length fi and wherein a first lens element L<NUM> faces an object side and a last lens element LN faces an image side;
an object side optical path folding element O-OPFE (<NUM>) for folding a first optical path (OP1) (<NUM>) to a second optical path (OP2) (<NUM>);
an image side optical path folding element I-OPFE (<NUM>) for folding OP2 (<NUM>) to a third optical path (OP3) (<NUM>), wherein OP1 (<NUM>) and OP2 (<NUM>) are perpendicular to each other and wherein OP1 (<NUM>) and OP3 (<NUM>) are parallel with each other; and
an image sensor (<NUM>) having a sensor diagonal (SD),
wherein the camera module (<NUM>) is a folded digital camera module, wherein G1 (<NUM>-G1) is located at an object side of the O-OPFE (<NUM>) and G2 (<NUM>-G2) is located at an image side of the O-OPFE (<NUM>), wherein the EFL is in the range of <NUM><EFL<<NUM>,
wherein the camera module (<NUM>) is divided into a first region having a minimum camera module region height MHM and including G1 (<NUM>-G1) and the O-OPFE (<NUM>), and into a second region having a minimum shoulder region height MHs < MHM and including the I-OPFE (<NUM>) and the image sensor (<NUM>), wherein all heights are measured along OP1, wherein an aperture height of the lens (<NUM>) is HL, wherein HL/MHS > <NUM>, wherein the camera module (<NUM>) has a minimum camera module length MLM and wherein EFL > <NUM>M.