Large-aperture continuous zooming folding long-focus camera and mobile device

Abstract

A folding digital camera and a mobile device, the camera including a lens including a plurality of N lens elements marked as Li, where 1 < = i < = N, where a first lens element L1 faces an object side and a last lens element LN faces an image side, and an optical path folding element (OPFE), where i is greater than or equal to 1 and less than or equal to N, where i is greater than or equal to 1 and less than or equal to N. Wherein at least one of the N lens elements is located on an object side of the OPFE and has an associated first optical axis, and the other at least one of the N lens elements is located on an image side of the OPFE and has an associated second optical axis, and wherein the lens has an effective focal length (EFL) and an f number (f / #), an image sensor has a sensor diagonal (SD), in which the EFL can vary continuously between a minimum EFLMIN and a maximum EFLMAX by independent movement of the lens element and the OPFE along the second optical lens axis, and in which EFLMAX / EFLMINgt; and 1.5. At least one defect of the prior art can be overcome.

Description

[0001] This application is a divisional application of the application with application number 202280008147.8, application date August 3, 2022, and invention title "Large Aperture Continuous Zoom Folding Telephoto Camera".

[0002] Cross - Reference to Related Applications

[0003] This application claims the priority of U.S. Provisional Patent Application No. 63 / 247,336, filed on September 23, 2021, the entire content of which is incorporated herein by reference. Technical Field

[0004] The subject matter of the present disclosure is generally related to the field of digital cameras. Background Art

[0005] Definitions

[0006] In this application and throughout the description and figures, the following symbols and abbreviations are used for optical and other characteristics, which are terms known in the art:

[0007] Total Track Length (TTL): When the system is focused on an infinite object distance, the maximum distance measured along an axis parallel to the optical axis of a lens from a point on the front surface S1 of a first lens element L1 to an image sensor.

[0008] Effective Focal Length (EFL): In a lens (the combination of lens elements L1 to L N ), the distance between the principal rear point P' and the rear focal point F' of the lens.

[0009] f-number (f / #): The ratio of the EFL to the diameter of the entrance pupil.

[0010] Background

[0011] Multi-aperture cameras (or "multi-cameras", with "dual-cameras" having two cameras being an example) are included in almost all current portable electronic mobile devices ("mobile devices", such as smartphones, tablets, etc.). Multi-cameras typically include a wide field of view (or "angle") FOV W camera ("wide" camera or "W" camera), and at least one additional camera, such as having a narrower (narrower than FOV W narrow) field of view (having FOV Tof a telephoto or “tele” camera). Generally, the spatial resolution of the telephoto camera is constant and can be, for example, 3 times or 5 times or 10 times higher than the resolution of the W camera. This is referred to as the telephoto camera having a “zoom factor” (ZF) of 3, 5, or 10, respectively. The ZF is determined by the EFL (EFL T ) of the telephoto camera.

[0012] For example, consider a dual camera having a W camera and a telephoto camera with a ZF of 5. When zooming into a scene, the image data of the W camera can be used, which is digitally zoomed to a ZF of 5. For ZF≥5, the image data of the telephoto camera can be used, which is digitally zoomed to a ZF>5. In some scenes, a high ZF is required to capture high-resolution images. In other scenes, due to the FOV T may be too narrow for a high ZF, and a high ZF is not desirable except that the image data of only the (digitally zoomed) wide camera is available. For example, the minimum ZF, ZF MIN and the maximum ZF, ZF MAX between which a continuous zoom factor can be provided are described in co-owned international patent applications PCT / IB2021 / 061078 and PCT / IB2022 / 052515.

[0013] Figure 1A FIG. shows a known folded telephoto camera 100, including an optical path folding element (OPFE) 102 having a width W OPFE , a lens 104 having N lens elements (not visible in this illustration) included in a lens barrel 110 at a distance ΔLO from the OPFE 102, and an image sensor 106. The OPFE 102 folds the optical path (OP) from a first OP 112 to a second OP 108 that forms the optical axis of the lens 104. The lens 104 is located on the image side of the OPFE 102. The theoretical lower limits of a length (“minimum module length” or “MML”) and a height (“minimum module height” or “MMH”) of a camera module including the camera 100 are shown. The MML and MMH are defined by the minimum dimensions of the elements included in the camera 100. The TTL is obtained from TTL = MML - W OPFE –ΔLO, so the TTL is geometrically limited by TTL < MML - W OPFE .

[0014] Figure 1BIllustrates a known dual camera 150, which includes a folding telephoto camera 100 and a (vertical or "upright") W camera 130. The W camera 130 includes a lens 132 having N lens elements (not visible in this figure) and an image sensor 138. The lens 132 is included in a lens barrel 134. The W camera 130 has an OP136.

[0015] Figure 1C Schematically shows in cross-section a known mobile device 160 (such as a smartphone). The mobile device 160 has an external rear surface 162 and includes a folding telephoto camera 100. The aperture of the camera 100 is located on the rear surface 162. A front surface 164 of the mobile device 160 may include a screen (not visible). The mobile device 160 has a conventional region 166 of a thickness ("T") and a camera bump region 168 that is raised a height B above the conventional region. The bump region 168 has a bump length ("BL") and a bump thickness T + B. Typically and as shown here, the camera 100 is fully integrated in the bump region 168 such that MML and MMH define the lower limits of the dimensions of the bump region 168, i.e., BL and T + B. Vice versa, the given dimensions of the bump region 168 constitute the upper limits of MML and MMH and the parts included. In particular, an aperture diameter ("DA") or "entrance pupil" of the camera 100 satisfies DA < MMH. For industrial design reasons, a compact camera bump (i.e., a short BL and a small B) is desired. Compared to a vertical camera (such as 130), for a given bump thickness T + B, a folding camera (such as 100) can achieve a greater TTL, corresponding to a greater ZF, which is desirable. However, a large TTL is accompanied by a large BL, which is not desirable.

[0016] It would be beneficial to have a continuously variable zoom folding telephoto camera with an aperture diameter DA that can provide a large EFL at a low f / # and still only occupy a small portion of the camera bump of the mobile device. SUMMARY OF THE INVENTION

[0017] In various exemplary embodiments, there is provided a folding digital camera, including: a lens including a plurality of N lens elements labeled L i where 1 ≤ i ≤ N, where a first lens element L1 faces the object side, and a last lens element L NFacing an image side, at least one of the N lens elements is located on the object side of the OPFE and has an associated first optical axis, and at least one of the other N lens elements is located on the image side of the OPFE and has an associated second optical axis, where the lens has an EFL and an f / #; and an image sensor has a sensor diagonal (SD), where by independent movement of the lens element and the OPFE along the second optical lens axis, the EFL can be between a minimum EFL MIN and a maximum EFL MAX continuously vary, and where EFL MAX / EFL MIN > 1.5.

[0018] In some examples, the lens is divided into two lens groups numbered G1 and G2, and the continuous variation of the EFL is obtained by independent movement of G1 and G2 respectively. In some examples, G1 includes three lens element subgroups G1-1, G1-2, G1-3 and the OPFE, where G1-1 is located on the object side of the OPFE and where G1-2 and G1-3 are located on the image side of the OPFE. In some examples, G2 includes two lens element subgroups G2-1 and G2-2, where G2-1 is located on the image side of G1-2 and where G2-2 is located on the image side of G1-3. In such an embodiment, G1-1 may include one lens element and where G1-2, G1-3, G2-1 and G2-2 may each include two lens elements.

[0019] In some examples, the EFL can be continuously varied by independently changing the positions of G1 and G2 along the second optical axis and by moving G1 + G2 together along the second optical axis relative to the image sensor.

[0020] In some examples, G1 and G2 can be moved together relative to the image sensor as a single lens for focusing. In some examples, the image sensor is operably moved relative to G1 and G2 for optical image stabilization (OIS). The movement of the image sensor for optical image stabilization is performed in two directions, and where the two directions are perpendicular to a normal on the image sensor and perpendicular to each other.

[0021] In some examples, a camera as described above or below can be included in a camera module having a shoulder height SH, and DA > SH. In some examples, SH is in the range of 4 mm < SH < 10 mm. In some examples, 5 mm < SH < 8 mm.

[0022] In some examples, DA > 1.1xSH. In some examples, DA > 1.2xSH. In some examples, DA > 1.2xSH. In some examples, DA is in the range of 5mm < DA < 11mm, and f / # is in the range of 1.8 < f / # < 6.0. In some examples, DA is in the range of 7mm < DA < 10mm, and f / # is in the range of 2.0 < f / # < 5.0.

[0023] In some examples, a camera is included in a camera module, and the camera module has a camera module height MH in the range of 6mm < MH < 12mm. In some examples, 7mm < MH < 11mm. In some examples, where SH is in the range of 4mm < SH < 10mm, and MH is in the range of 6mm < SH < 12mm, a ratio SH / MH < 0.9, or < 0.8 or even < 0.7.

[0024] In some examples, an f / # at EFL MIN is f / # MIN , an f / # at EFL MAX is f / # MAX , and where a ratio f / # MAX / f / # MIN < EFL MAX / EFL MIN . In some examples, f / # MAX / f / # MIN < EFL MAX / 1.1x EFL MIN .

[0025] In some examples, the lens can be a cut lens, and all lens elements located on the image side of the OPEE are cut along an axis parallel to the second optical axis.

[0026] In some examples, the lens can be a cut lens, where all lens elements located on the object side of the OPEE are cut along an axis parallel to the first optical axis, and all lens elements located on the image side of the OPEE are cut along an axis parallel to the second optical axis.

[0027] In some examples with a cut lens, the lens is cut 30% with respect to the diameter of an axisymmetric lens. In some such examples, with respect to an axisymmetric lens having the same lens diameter measured along an axis perpendicular to the first optical axis and the second optical axis of the lens, the SH is reduced > 20% by the cut. In some such examples, a ratio SH / DA is reduced > 10%.

[0028] In some examples, G1-1 includes L1. In some examples, a focal length of L1 is f1, and f1 < 1.1x EFL MIN .

[0029] In some examples, L1 is made of glass.

[0030] In some examples, N = 9. In some examples, a focal power sequence of lenses L1-L9 is positive-negative-negative-positive-negative-positive-negative-negative-positive.

[0031] In some examples, L2 is the first lens element located on the image side of the OPFE, and a distance between the OPFE and L2 is labeled as d M-L , and d M-L does not change due to continuous change of EFL. In some examples, a ratio d M-L / TTL < 7.5%.

[0032] In some examples, the last lens L N is positive.

[0033] In some examples, L1 is the only lens element located on the object side of the OPFE, a distance between L1 and the OPFE is ΔLO, and a ratio ΔLO / TTL < 1%. In some examples, ΔLO / TTL < 0.5%.

[0034] In some examples, the OPFE can be a mirror.

[0035] In some examples, EFL MAX / EFL MIN > 1.75. In some examples, EFL MAX / EFL MIN > 1.9.

[0036] In some examples, 30mm < EFL MAX < 50mm and 10mm < EFL MIN < 30mm.

[0037] In some examples, SD can be in the range of 3mm < SD < 10mm.

[0038] In various exemplary embodiments, a mobile device is provided that includes a camera as described above or below. A mobile device has a device thickness T and a camera bump region, where the bump region has a raised thickness T + B, where a first region of the camera is included in the camera bump region, and where a second region of the camera is not included in the camera bump. The mobile device can be a smartphone. In some such mobile devices, N = 9, the first region of the camera includes L1 and the OPEE, and the second region of the camera includes lens elements L2 - L9 and the image sensor. In some examples, the mobile device may further include a second camera having a second camera lens with a second EFL (EFL2), where EFL2 < EFL MIN . BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Non - limiting examples of the embodiments disclosed herein are described below with reference to the drawings listed later in this section. The specification drawings and the specification are intended to illustrate and clarify the embodiments disclosed herein and should not be considered limiting in any way.

[0040] Figure 1A A known folded telephoto camera is depicted;

[0041] Figure 1B A known dual - camera is depicted;

[0042] Figure 1C A known mobile device is schematically shown having an external rear surface and including a folded telephoto camera;

[0043] Figure 2A An embodiment of the folded telephoto camera disclosed herein is schematically shown;

[0044] Figure 2B Schematically shown in cross - section is a mobile device with dimensions as Figure 1C described, the mobile device having an external rear surface and including a folded telephoto camera as Figure 2A ;

[0045] Figure 2C Shown is Figure 2A an embodiment of an autofocus (AF) mechanism of the folded camera of

[0046] Figure 2D Shown is for Figure 2A an embodiment of an OIS mechanism of the folded camera of

[0047] Figure 3AAn embodiment of an optical lens system disclosed herein is schematically shown in a first zoom state.

[0048] Figure 3B The embodiment disclosed herein is schematically shown in a second zoom state Figure 3A .

[0049] Figure 3C A lens travel required for continuous zoom Figure 3A to B of the optical lens system is shown;

[0050] Figure 3D Another embodiment of an optical lens system disclosed herein is schematically shown in a first zoom state.

[0051] Figure 3E The embodiment disclosed herein is schematically shown in a second zoom state Figure 3D ;

[0052] Figure 4A The orthographic projections IP orth,1 , IP orth,2 of two impact points IP1 and IP2 on a plane P are shown;

[0053] Figure 4B The orthographic projections IP orth,3 , IP orth,4 of two impact points IP3 and IP4 on the plane P are shown;

[0054] Figure 5A The definition of clear height (CH) is provided;

[0055] Figure 5B The definition of clear aperture (CA) is provided;

[0056] Figure 6 The definitions of H L and H opt are provided;

[0057] Figure 7 A lens barrel including a plurality of cutting lens elements and a lens housing is shown. DETAILED DESCRIPTION

[0058] In the following detailed description, numerous specific details are given to provide a thorough understanding. However, those skilled in the art will understand that the present invention can be practiced without these specific details. In other instances, well-known methods will not be described in detail so as not to obscure the present invention.

[0059] Figure 2AAn embodiment of a folded continuous zoom telephoto camera disclosed herein and numbered 200 is schematically shown. The camera 200 includes a lens 202 having N lens elements. In the lens 202, for example, N = 4. The lens elements in the lens 202 are numbered L1 - L4, where L1 is oriented towards an object side. Each lens element L i (where "i" is an integer between 1 and N). L1 is axisymmetric along a first optical (lens) axis 212, and L2 - L4 are axisymmetric along a second optical (lens) axis 208. The lens 202 further includes an OPFE 204 that folds OP 212 to OP 208. The camera 200 further includes an image sensor 206. The camera elements may be included in a housing 214.

[0060] The lens 202 is divided into two or more lens groups G1 (here including L1, OPFE 204, and L2) and G2 (here including L3 and L4), where the lens elements included in G1 are located on an object side (L1) of the OPFE 204 and an image side (L2) of the OPFE 204. G2 is located on an image side of the OPFE 204.

[0061] To estimate the theoretical limits of the minimum size of a camera module of an optical lens system including, for example Figures 2A - 2D and 3A - 3E, we introduce the following parameters and interdependencies:

[0062] MML and "Module Length" ("ML")

[0063] - The minimum module length ("MML") is the theoretical lower limit of the length of a camera module including all parts of the camera 200.

[0064] - MML = max(Z Lens , Z OPFE ) - Z Sensor , max(Z Lens , Z OPFE ) is the maximum value of the length occupied by the lens 202 along the z - axis (Z Lens ) or the OPFE 204 (Z OPFE ), and Z Sensor is the minimum value of the length occupied by the image sensor 206 along the z - axis. In some examples and as Figure 3A - B shows, Z Lens > Z OPFE , so MML = Z Lens – Z Sensor .

[0065] - To achieve an actual estimate of a length (“ML”) of a camera module, a length such as 3.5 mm can be added to MML, i.e., ML = MML + 3.5 mm (see Table 4). The additional length takes into account a lens travel that may be required for AF, OIS, and image sensor packaging, housing, etc. To calculate ML, when considering all possible EFLs used, the highest value of MML is given by the MML value at EFL MAX is given.

[0066] R1

[0067] - A first region (“R1”) of MML is associated with a first minimum module height MMH1. MMH1 is the theoretical lower limit of the height of a camera module that includes all parts of camera 200 located in R1.

[0068] - R1 = max(WL, W OPFE ), where WL is the width of G1 measured along the z-axis, and W OPFE is the width of OPFE 204 measured along the z-axis. In some examples and as Figure 3A - shown in E, WL > W OPFE , so R1 is independently determined by G1 and R1 = WL.

[0069] - Given a specific MML, see Figure 2A , it is beneficial to minimize R1 because it constitutes a lower limit for the bump length (BL).

[0070] R2

[0071] - A second region (“R2”) of MML is associated with a second minimum module height MMH2, and MMH2 < MMH1.

[0072] - R2 = MML - R1.

[0073] - For a given MML and to minimize BL, it is beneficial to maximize R2 (minimize R1).

[0074] MMH1 and "Module Height" ("MH")

[0075] - MMH1 = H OPFE + ΔLO + TG1, where H OPFE is the height of OPFE 204 (OPFE 204 is oriented at 45 degrees with respect to both the y-axis and the z-axis, so H OPFE = W OPFE ), and ΔLO is the distance between the center of G1 and OPFE 204.

[0076] - In some examples and as Figure 3A - shown in -B, the lens elements in lens 202 have a lower y-value than OPFE 204, so MMH1 is determined by the highest y-value of G1 (Y G1 ) and the lowest y-value of lens 202 (Y Lens ): MMH1 = Y G1 – Y Lens . In some examples using a cutting lens and as Figure 3D - shown in -E, Y Lens is lifted, so Y Lens > Y OPFE , and as Figure 2B shown, MMH1 is not limited by the lens but only by H OPFE .

[0077] - To achieve an actual estimate of the height of a camera module, we calculate MH by adding an additional height of 1.5 mm to MMH1, i.e., MH = MMH1 + 1.5 mm (see Table 4). The additional length takes into account the AF and the lens travel that may be required for the housing, lens cover, etc.

[0078] MMH2 and "Shoulder Height" ("SH")

[0079] - A second minimum module height (“MMH2”) is the theoretical lower limit of the height of a camera module that includes all elements of camera 200 in R2.

[0080] - MMH2 = min(HS, H Lens ), where HS is the height of image sensor 206 and H Lens is the height of the highest lens element of lens 202 located in R2, both measured along the y-axis.

[0081] - In certain examples and as Figure 2A shown, MMH2 can be determined by image sensor 206, i.e., MMH2 = HS. In other embodiments and as Figure 3A - shown in -E, MMH2 can be determined by the lowest Y-value of a mirror 304 on one side and the height of lens elements L2-L9 on the other side.

[0082] - To achieve an actual estimate of the true camera shoulder height, the shoulder height SH is calculated by adding an additional height, such as 1.5 mm, to MMH2, i.e., SH = MMH2 + 1.5 mm (see Table 4). The additional height takes into account the electrical and mechanical contact with sensor 206 and the housing.

[0083] The first advantage of the folded camera 200 over a known folded camera such as the camera 100 is that the aperture diameter DA of the camera 200 is not necessarily limited by SH. Typically, in a folded camera, all lens elements are located on an image side of the OPFE, so SH physically limits DA, and SH>DA. Being able to have DA>SH and allowing relatively low f / # even at high ZF is not the case with the camera 200.

[0084] Furthermore, given an OPFE of a particular size such as OPFE 204 (e.g., limited by T and / or B), camera 200 can provide greater DA, allowing for relatively low f / # even at high ZF. This is based on the fact that L1 is located on an object side of OPFE 204 (or more generally, includes one or N lens elements located on an object side of the OPFE in G1). The refractive power of L1 reduces the diameter of a cone of light entering folded camera 200 before the cone of light hits OPFE 204, allowing a greater amount of light to enter the camera for a particular size of an OPFE than known folded cameras that do not have any lenses located on an object side of an OPFE.

[0085] The TTL of camera head 200 is not oriented in one dimension, but in two dimensions. The first part ("TTL1") is parallel to OP 212, and the second part TTL2 ("TTL2") is parallel to OP 208. TTL is derived from TTL = TTL1 + TTL2. Therefore, TTL is not affected by TTL. <MML-W OPFE geometric limitations, so for a given MML, a TTL can be significantly greater than the TTL of camera 100.

[0086] Figure 2B The cross-sectional view schematically shows a Figure 1C A mobile device of the described dimensions, the mobile device having an external rear surface 200 and including a folded telephoto camera 200 as disclosed herein. The camera bump area is marked as 228. A front surface 224 of the mobile device 220 may, for example, include a screen (not visible). R1 ​​of the camera 200 is integrated into 224 of height T+B, while R2 of the camera 200 is integrated into the conventional device area 226 of height T. The mobile device 220 in which the camera 200 is only partially integrated into the bump area may have a smaller BL compared to the mobile device 160 in which the camera 100 is fully integrated into the bump area, or, for example, integrate additional cameras into 228, which may be beneficial for industrial design reasons. In general, for slim mobile devices, it is beneficial to minimize MMH1 and MMH2.

[0087] Figure 2CIllustrates how autofocus (AF) is performed in the camera 200 in one example Figure 2D Schematically illustrates how optical image stabilization (OIS) is performed in the camera 200 in one example. The lens 202 including the OPFE 204 is shown in the same direction as in Figure 2A to B. For illustrative purposes Figure 2C and Figure 2D only the elements of the camera 200 that move for AF or OIS respectively are shown. As shown by arrow 232, the lens 202 including the OPFE 204 moves as a unit along an axis parallel to the z-axis for AF with respect to the image sensor (not shown). The moving lens 202 includes the OPFE 204 as a unit, meaning that the distances between the N lens elements (here L1 - L4) and the distance between the lens 202 and the OPFE 204 do not change. Only the distance to the image sensor (not shown) changes. Since the lens (including the OPFE) moves with respect to the image sensor, it can be said to be "lens autofocus (AF)".

[0088] The image sensor 206 is shown in the same direction as Figure 2A -B. As shown by arrow 234, the image sensor 206 moves along a first sensor OIS axis ("OIS1") parallel to the x-axis with respect to the lens 202 (not shown here) including the OPFE 204 (not shown here) to perform OIS along a first axis. As shown by arrow 236, the image sensor 206 moves along a second sensor OIS axis ("OIS2") parallel to the y-axis with respect to the lens 202 (not shown here) including the OPFE 204 (not shown here) to perform OIS along a second axis. Since the image sensor moves with respect to other camera elements, it can be said to be "sensor OIS".

[0089] Figures 3A - 3E Illustrates the optical lens system disclosed herein. As Figure 2A -B shows, all the lens systems shown can be included in a folding camera and a mobile device. It should be noted that all the embodiments disclosed herein are beneficial for use in smartphones.

[0090] Figure 3A Schematically shows an embodiment of an optical lens system disclosed herein, the optical lens system having an EFL MINIn the first, minimum zoom state with a focal length of 20 mm, the number is 300. The lens system 300 includes a lens 302, an optical element 309, and an image sensor 306. The lens 302 includes an OPFE 304 (exemplarily a mirror here). The system 300 is shown with ray tracing. The optical element 309 is optional and can be, for example, an infrared (IR) filter and / or a glass dust cover for the image sensor. In other embodiments, the OPFE 304 can be a prism.

[0091] The lens 302 includes a mirror 304 and N lens elements L i . In this example of the lens 302, N = 9. L1 is the lens element closest to the object side, and L N is the lens element closest to the image side, i.e., the side where the image sensor is located. This order applies to all lenses and lens elements disclosed herein. L1 is axisymmetric about a first optical (lens) axis 312, and L2 - L9 are axisymmetric about a second optical (lens) axis 308. Each lens element L i includes a corresponding front surface S 2i-1 (the label "2i - 1" is the number of the front surface) and a corresponding rear surface S 2i (the label "2i" is 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, the lens surfaces are labeled as "S k ", where k ranges from 1 to 2N.

[0092] In all optical lens systems disclosed herein, the aperture diameter DA of the camera is determined by L1.

[0093] As used herein, the term "front surface" of each lens element refers to the surface of a lens element located near the entrance of the camera (the object side of the camera), and the term "rear surface" refers to the surface of a lens element located near the image sensor (the image side of the camera).

[0094] Figure 3B An optical lens system 300 in the second, maximum zoom state with an EFL MAX = 40 mm is shown. As described in Table 3 and Figure 3C , to change the ZF, G2 moves relative to G1 and the image sensor 306, and additionally G1 + G2 moves together as a lens relative to the image sensor 306 (for focusing to infinity). To focus to a finite distance, G1 and G2 move together as a lens relative to the image sensor 306.

[0095] The mirror 304 is oriented at a 45-degree angle with respect to the y-axis and the z-axis. Light passes through G1-1, is reflected by the mirror 304, and successively passes through G1-2, G2-1, G1-3, G2-2, and forms an image on the image sensor 306. Figure 3A -B and Figure 3D -E show five fields, each field having 3 light rays.

[0096] MMH1 and MMH2 are defined by L2-L9. In particular, MMH2 is defined by the largest lens element L6. The values are given in Table 4. The detailed optical data and surface data are given in Tables 1-3 for Figure 3A -B and the examples of the lens elements in 3D-E. The values provided for these examples are purely illustrative, and according to other examples, other values can be used.

[0097] The surface type is defined in Table 1. The coefficients of the surface are defined in Table 2. The surface types are:

[0098] a) Plano: flat, no curvature

[0099] b) Q type 1 (QT1) surface sag formula:

[0100]

[0101] where {z,r} are standard cylindrical polar coordinates, c is the paraxial curvature of the surface, k is the conic parameter, r norm is generally half of the clear aperture of the surface, and A n is the polynomial coefficient shown in the lens data sheet. The Z-axis is positive towards the image. The value of CA is given in terms of a clear aperture radius, i.e., CA / 2. CA varies with the change of EFL, and the value of an effective aperture diameter is given in Table 4. These values are also used to calculate an F / # in Table 3. The reference wavelength is 555.0 nm. The unit is millimeter, except for the refractive index (“Index”) and the Abbe number (Abbe#). Each lens element L i has a respective focal length f i . The FOV is given in the form of half of the FOV (HFOV). The definitions of the surface type, Z-axis, CA value, reference wavelength, unit, focal length, and HFOV apply to all further presented tables. The width of the mirror is 9.4 mm x 7.1 mm and is tilted at 45 degrees. The semi-diameter of the mirror is defined by the circle around it. The thickness relative to the mirror is relative to the optical axis. Table 3 gives the values at EFL MIN and EFLMAX between, and the movement between the lens elements required for continuous switching between HFOV and f / #

[0102] continuously switch.

[0103]

[0104]

[0105] Table 1

[0106]

[0107] Table 2

[0108]

[0109]

[0110] Table 3

[0111] Figure 3C shows the movement of each element of the lens 302 relative to the image sensor 306, which movements are required for continuous switching between different EFLs (i.e., ZF), thus maintaining focus at infinity. Based on the movements, two lens groups G1 and G2 can be defined. G1 includes L1, mirror 304, L2, L3, L6, and L7. G2 includes L4, L5, L8, and L9.

[0112] The continuous change of the EFL is obtained by the independent relative movement of G1 and G2 and by moving G1 + G2 together relative to the image sensor, both movements being along the optical axis 308. All elements respectively included in G1 and G2 are fixedly coupled to each other, which means that they can move relative to other elements included in the optical system 300, such as relative to the image sensor 306, but they do not move relative to each other. Specifically, G1-1 does not move relative to mirror 304, G1-2, and G1-3. G2-1 does not move relative to G2-2. As shown, the maximum movement stroke of G2 relative to the sensor 306 is 8.7 mm, and the maximum movement stroke of G1 relative to the sensor 306 is 4.0 mm.

[0113] As Figure 3A -B shows, G1 includes three lens groups G1-1 (including L1), G1-2 (including L2 and L3), and G1-3 (including L6 and L7). G2 includes lens groups G2-1 (including L4 and L5) and G2-2 (including L8 and L9). Starting from the object side of the camera 300, the numbers of G1-1, G1-2, etc. are completed according to the positions of the lens element groups along the optical paths 312 and 308.

[0114] AsFigure 3A As shown in FIGS. -B and 3D-E, d M-L is a distance measured between the mirror 304 and L2. d M-L does not change with the continuous change of the EFL, that is, when the ZF is changed, there is no relative movement between the mirror 304 and L2.

[0115] Figure 3D Another embodiment of an optical lens system disclosed herein is schematically shown, and the optical lens system is numbered 350 in the first and minimum zoom state with an EFL MIN = 20 mm. The lens system 350 includes a lens 302-C, and the lens 302-C includes a mirror 304, an optical element 309 (optional), and an image sensor 306. The lens 350 is obtained by cutting the lens element of the optical lens system 300:

[0116] -L1 is cut to 8 mm (D / 2 = 4 mm), that is, WL1 = 8 mm.

[0117] -L2-L9 is cut to 4.6 mm (D / 2 = 2.3 mm).

[0118] The cutting of L1 is performed in a direction parallel to the y-axis, reducing WL1 measured along the z-axis. For the optical lens system 300, this results in a smaller R1 and a smaller MML. The cutting of L2-L9 is performed in a direction parallel to the z-axis, reducing the width of the lens element measured along the y-axis. For the optical lens system 300, this results in a smaller MMH1 and a smaller MMH2.

[0119] Referring to Figure 7 the coordinate system shown, the cutting is performed such that a lens width WL measured in a y direction (“WL Y ”) is less than a WL measured in an x direction (“WL X ”), that is, WL Y < WL X (see Figure 7 ).

[0120] Relative to the diameter of the largest lens element in 302 (L6), 302-C is cut by approximately 30%. During cutting, MMH1 and MMH2 are not defined by L2-L9, but by the mirror 304. Relative to the uncut lens 302, for the cut lens 302-C, SH is reduced by 18% and the ratio SH / DA is reduced by 12% (see Table 4).

[0121] Figure 3E Shows the second and maximum zoom state and with an EFL MAXAn optical lens system 350 with a focal length of 40 mm.

[0122] Table 4 summarizes the numerical values and their ratios of various features included in Figures 3A - 3E the lens systems 300 and 350 shown, where the values of d M-L , ΔLO, SD, TTL, MML, DA, H L6 , MMH, R1, R2, SH, MH are given in millimeters. The values in the "Ratio 350 / 300" column are calculated by dividing a corresponding value obtained in the optical lens system 350 by a value obtained in the optical lens system 300. The values in the "Range" column represent the preferred ranges that can be included in other examples.

[0123] - DA is the aperture diameter. For all lens systems, an effective aperture diameter is given.

[0124] - H L6 is the height of the largest lens element on the image side of the mirror 304.

[0125] - F / # MIN and F / # MAX represent the F / # at EFL MIN and EFL MAX respectively.

[0126]

[0127] Table 4

[0128] As described below, a net height value CH(S k ) can be defined for each surface S where 1 ≤ k ≤ 2N, and a net aperture value CA(S k ) can be defined for each surface S where 1 ≤ k ≤ 2N. CA(S k ) and CH(S k ) define the optical characteristics of each surface S of each lens element. The CH term is defined with reference to k as described below, and the CA term is defined with reference to k as described below. k Figure 5A In addition, a height ("H Figure 5B ", for 1 ≤ i ≤ N) is defined for each lens element L

[0129] . For each lens element L i , H Li corresponds to the lens element L measured along the axis perpendicular to the optical axis of the lens element i , and H Li is measured along the axis perpendicular to the optical axis of the lens element L iThe maximum height. For a given lens element, the height is greater than or equal to the net height value CH and the net aperture value CA of the front and rear surfaces of this given lens element. Generally, for an axially symmetric lens element, such as Figure 6 shown, H Li is the diameter of the lens element L i . Generally, for an axially symmetric lens element, H Li = max{CA(S 2i-1 ), CA(S 2i )} + mechanical part dimension. Generally, in lens design, the mechanical part dimension is defined as not contributing to the optical characteristics of the lens. Due to this, one defines two heights of the lens: an optical height H opt (corresponding to the CA value) of an optically effective range 602 and a geometric (or mechanical) height H L of the entire lens range 604 covering an optically effective range and an optically ineffective range. The mechanical parts and their attributes are defined as follows. The contribution of the mechanical part dimension to H Li is generally 200 - 1000 μm.

[0130] As Figure 4A , 4B and 5A, 5B show, each ray passing through a surface S k (for 1 ≤ k ≤ 2N) strikes this surface at the impact point IP. The ray enters the camera 200 from the surface S1 and passes through the surfaces S2 to S 2N . Some rays can strike any surface S k but cannot / will not reach the image sensor 206. For a given surface S k , only the rays that can form an image on the image sensor 206 are considered. CH(S k ) is defined as the distance between the two closest parallel lines (see the lines 500 and 502 located on a plane P orthogonal to the optical axis of the lens element in Figure 5A ). In the representations of Figure 4A and 4B , the plane P is parallel to the plane X - Y and orthogonal to the optical axis 402, such that all the impact points IP have their orthogonal projections IP orth on the plane P located between the two parallel lines. CH(S k ) can be defined for each surface S k (front and rear surfaces, 1 ≤ k ≤ 2N).

[0131] CH(S k) is defined independently of the object being imaged currently, because it refers to the light rays that "can" form the image on the image sensor. Thus, even if the object being imaged currently is located in a black background that does not produce light, the definition does not refer to this black background, because it refers to any light rays (e.g., light rays emitted by a luminous background, as opposed to a black background) that "can" reach the image sensor to form an image.

[0132] For example, Figure 4A illustrates the orthogonal projections IP of two impact points IP1 and IP2 on a plane P orthogonal to the optical axis 402 orth,1 、IP orth,2 . For instance, in Figure 4A 's representation, the surface S k is convex.

[0133] Figure 4B illustrates the said orthogonal projections IP of two impact points IP3 and IP4 on the plane P orth,3 、IP orth,4 . For instance, in Figure 4B 's representation, the surface S k is concave.

[0134] In Figure 5A , for a surface S k , the orthogonal projections IP of all impact points IP on the plane P orth are located between the parallel lines 500 and 502. CH(S k ) is thus the distance between the lines 500 and 502.

[0135] As Figure 5B is known and shown, for each given surface S k (for 1 ≤ k ≤ 2N), a net aperture CA(S k ) is defined as the diameter of a circle, where the circle is the smallest possible circle in a plane P orthogonal to the optical axis 402 and encloses all the orthogonal projections IP orth of all impact points on the plane P. As described above with respect to CH(S k ), the definition of CA(S k ) also does not depend on the object being imaged currently.

[0136] As Figure 5B is shown, the circumscribed orthogonal projection IP orth of all impact points IP on the plane P is a circle 510. The diameter of the circle 510 defines CA(S k ).

[0137] Figure 7Shows a lens barrel 700 including a plurality of cutting lens elements and a lens housing 704. The first cutting lens element L1 702 is visible. L1 has a width along the x-axis (“WL X ”), the width being greater than the width along the z-axis (“WL Z ”), i.e., WL X >WL Z . The x-axis, y-axis, and z-axis are oriented the same as Figure 3A -B and 3D-E.

[0138] It should be understood that, for clarity, the specific features of the invention described in different embodiments may also be provided in combination in a single embodiment. Conversely, for brevity, the various features of the invention described in a single embodiment may also be provided separately, or in any suitable sub-combination.

[0139] Unless otherwise stated, the use of the expression “and / or” between the first two members of an option list indicates that one or more selections of the options of the list are appropriate and may be chosen.

[0140] It should be understood that where a claim or specification refers to “a” or “an” element, such reference should not be construed as meaning only one of that element.

[0141] All patents and patent applications mentioned in this specification are hereby incorporated by reference in their entirety into the specification, as if each individual patent or patent application was specifically and individually indicated to be incorporated by reference herein. In addition, the citation or identification of any reference in this application should not be construed as an admission that such reference is available as prior art against the present invention.

Claims

1. A camera, characterized in that: The camera includes: A lens including a plurality of effective optical surfaces and an optical path folding element OPFE, each effective optical surface providing a refractive power; An image sensor; Wherein the plurality of effective optical surfaces are divided into two lens groups labeled G1 and G2; The plurality of effective optical surfaces within one lens group do not move relative to each other; A single effective optical surface is located on the object side of the OPFE and has an associated first optical axis; The other effective optical surfaces are located on the image side of the OPFE and have an associated second optical axis; The lens has an effective focal length EFL, EFL < 50 mm; wherein, by independent movement of the G1 and G2 along the second optical lens axis, the EFL can be continuously varied between a minimum EFL MIN and a maximum EFL MAX ; and where EFL MAX / EFL MIN is equal to or greater than 1.

5.

2. The camera according to claim 1, characterized in that: EFL MAX / EFL MIN is equal to or less than 2.

3. The camera according to claim 1, characterized in that: The camera has an aperture diameter DA and is included in a camera module, the camera module having a shoulder region with a shoulder height SH, where the SH is measured in a direction along the first optical axis and is equal to 1.5 mm plus the height of the higher of the following: the height of the image sensor or the height of the highest of the plurality of effective optical surfaces located on the image side of the OPFE, and where DA > SH.

4. The camera according to claim 1, characterized in that: The image sensor is operable to move relative to G1 and G2 to achieve optical image stabilization OIS and focusing.

5. The camera according to claim 1, characterized in that: G1 includes three lens sub - groups G1 - 1, G1 - 2, G1 - 3 and the OPFE, where G1 - 1 is located on the object side of the OPFE, and where G1 - 2 and G1 - 3 are located on the image side of the OPFE.

6. The camera according to claim 1, characterized in that: G2 includes a plurality of lens sub - groups G2 - 1 and G2 - 2, where G2 - 1 is located on the image side of G1 - 2 and on the object side of G1 - 3, and where G2 - 2 is located on the image side of G1 - 3.

7. The camera according to claim 4, characterized in that: The movement of the image sensor for the OIS is carried out in two directions, and the two directions are perpendicular to a normal on the image sensor and perpendicular to each other.

8. The camera according to claim 1, characterized in that: The camera has an f-number f / # at EFL MIN and an f-number f / # at EFL MIN and a ratio of f / # MAX / f / # MAX where <EFL MAX / EFL MIN MAX MIN .​​ 9. The camera according to claim 1, characterized in that: The camera has an f-number f / # at the EFL MIN and an f-number f / # at the EFL MIN where f / # MAX <3 and f / # MAX <5. MIN MAX ​​ 10. The camera according to claim 1, characterized in that: The lens is a cut lens.

11. The camera according to claim 1, characterized in that: The distance between the OPFE and a first effective optical surface located on the image side of the OPFE is denoted as d M-L , where d M-L does not change with the continuous change of the EFL.

12. The camera according to claim 1, characterized in that: The OPFE is a prism.

13. The camera according to claim 1, characterized in that: The OPFE is a mirror.

14. The camera according to claim 1, characterized in that: 10mm < EFL MIN < 30mm。 15. The camera according to claim 1, characterized in that: The image sensor has a sensor diagonal SD, and 3 mm < SD < 10 mm.

16. The camera according to claim 3, characterized in that: 5 mm < DA < 11 mm, where 1.8 < f / # < 6.

0.

17. The camera according to any one of claims 1 to 16, characterized in that: The camera is included in a smart phone.

18. The camera according to claim 1, characterized in that: The camera is included in a camera module, the camera module having a shoulder height SH and a camera module height MH of the shoulder region, where the SH is measured in a direction along the first optical axis and is equal to 1.5 mm plus the height of the higher of the following: the height of the image sensor or the height of the highest of the plurality of effective optical surfaces located on the image side of the OPFE, where the SH is in the range of 4 mm < SH < 10 mm, the MH is in the range of 6 mm < MH < 12 mm, and a ratio SH / MH < 0.

9.

19. A mobile device, characterized in that: The mobile device includes the camera as claimed in claim 18, wherein the mobile device has a device thickness T and a camera bump region, wherein the camera bump region has a raised thickness T + B, wherein multiple portions of the shoulder region are not incorporated into the camera bump region, and another region of the camera is incorporated into the camera bump region.

20. The mobile device according to claim 19, characterized in that: The mobile device further includes a second camera, the second camera having a second effective focal length EFL2, and wherein EFL2 < EFL MIN .

21. The mobile device according to claim 19, characterized in that: The mobile device is a smart phone.

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