Thin pop-out wide camera lens and pop-out camera actuator

Abstract

Passive pop-out cameras for incorporation in foldable mobile electronic devices such as smartphones, lens systems for such cameras, and in some examples passive and in some examples shape memory alloy based pop-out actuators for actuating lens systems and other components in such cameras.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 383,721, filed November 15, 2022; U.S. Provisional Patent Application No. 63 / 492,538, filed March 28, 2023; U.S. Provisional Patent Application No. 63 / 495,148, filed April 10, 2023; U.S. Provisional Patent Application No. 63 / 518,110, filed August 8, 2023; and U.S. Provisional Patent Application No. 63 / 507,108, filed June 9, 2023, all of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure relates generally to digital cameras, and more specifically to digital cameras having a pop-out (“PO”) mechanism and a lens.

[0004] definition

[0005] In this application, the following symbols and abbreviations are used for optical properties and other properties mentioned throughout the specification and drawings, all of which are terms known in the art:

[0006] Total track length (TTL): The maximum distance between a point on the front surface S1 of the first lens element L1 and the image sensor, measured along an axis parallel to the lens optical axis when the system is focused to infinity.

[0007] Back focal length (BFL): The minimum distance between the point on the back surface S2N of the last lens element LN, measured along an axis parallel to the lens optical axis, and the image sensor when the system is focused to infinity.

[0008] Effective focal length (EFL): In a lens (an assembly of lens elements L1 to LN), the distance between the rear principal point P' and the rear focal point F'.

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

[0010] Multi-aperture digital cameras (or multi-cameras) are standard in today’s mobile electronic devices (or simply “mobile devices”, such as smartphones, tablets, laptops, PDAs, head-mounted devices, etc.). Typically, multi-cameras comprise a wide camera acting as the main (or “primary”) camera of the mobile device, an Ultrawide (UW) camera, and (optionally) a Tele camera. The main (or wide) camera has a wide camera sensor and a wide camera field of view (FOV W ), the UW camera has a UW camera sensor and a UW camera field of view (FOV UW >FOV W ), and the Tele camera has a Tele camera sensor and a Tele camera field of view (FOV T <FOV W ). One major challenge is to support ever higher image quality (IQ) and still fit the wide camera design into thin mobile devices having, for example, a device height of less than 12.5 mm. To improve IQ, ever larger image sensors are incorporated in mobile devices. Such large image sensors can have an optical format of more than 1 / 2”, i.e. they have a sensor diagonal (“SD”) of more than 8 mm, e.g. 1 / 1.5” (SD = 10.7 mm) or even 1 / 1” (SD = 16 mm). P-O cameras allow incorporating large image sensors while still supporting the slim thickness of mobile devices comprising the PO camera. PO cameras are described, for example, in commonly owned international patent application PCT / IB2020 / 058697.

[0011] FIG. 1A The definitions of various camera entities such as TTL, EFL, and BFL are schematically illustrated. In most micro-lenses used in multi-cameras incorporated in mobile devices, the TTL is larger than the EFL, e.g. for wide lenses as shown in FIG. 1A .

[0012] FIG. 1B An exemplary camera with a lens with a field of view (FOV), an EFL, and an image sensor with a sensor width S is shown. For a fixed width / height ratio and (rectangular) image sensor, the (full) image sensor diagonal (SD) is proportional to the sensor width and height. A typical width / height ratio of an image sensor is 4:3. For example, a 1 / 1.2” sensor has a SD of 14.3 mm. The diagonal FOV relates to the EFL and the SD as follows:

[0013]

[0014] This indicates that a large EFL is required to implement a camera with a large image sensor but similar FOV. It is desirable to incorporate a large image sensor in a wide camera, but in order to maintain the same FOV W , a large EFL is required, resulting in a large TTL, which is undesirable for integration in slim mobile devices.

[0015] Figure 1C schematically illustrates a mobile device 100 including a known PO camera (“POC”) 110 in a first state (“retracted state”) when the camera is not in use (or inactive). In the retracted state, the POC 110 has a first TTL (“retracted TTL” or “c-TTL”) as labeled. The c-TTL is compatible with the height dimension of modern mobile devices, i.e. in the retracted state, the PO camera 110 does not exceed the height (or thickness) of the mobile device 100. The height of the mobile device 100 can include the raised area of the mobile device 100 (the “camera bump” or simply “bump”) in which the multi-camera is included. The c-TTL can be in the range of 5-15 mm.

[0016] Figure 1D schematically illustrates a mobile device 100 including a POC 110 in a second state (“popped out” or “PO state”). Typically, only in the PO state, the POC can work as a camera. In the PO state, the POC 110 has a second TTL (“TTL”) as labeled. TTL > c-TTL, such that the POC 110 exceeds the height of the mobile device 100. In other words, in the PO state, the POC 110 protrudes (or “pops out”) from the mobile device 100. Typically, the mobile device has a thickness (“T”) of about T = 5-20 mm. The TTL can be in the range of 6-25 mm. The POC can protrude from the mobile device 100 about 1-15 mm.

[0017] To switch the POC 110 from the PO state to the collapsed state, an active actuator is needed, e.g. a stepper motor, a shaped metal alloy (SMA) actuator, etc. “Active” here means that the actuation requires electric power. Typically, to switch the POC 110 from the collapsed state to the PO state, an active actuator is not needed, but a passive actuator, e.g. based on spring force, is sufficient. In this disclosure, the term “passive” indicates that the actuator and / or the actuation does not require electric power. Recently, “foldable mobile devices” such as “foldable phones” (“FPs”) have been introduced, such as the Samsung Galaxy Fold or the Samsung Galaxy Flip. The FP can be “folded”. When folded, the FP achieves a small size, which is convenient. When unfolded, the FP provides a large screen area for the main screen, which is also convenient. Typically, when folded, the main screen of the FP is inactive.

[0018] POCs including SMA actuators are described, e.g. in co-owned international patent application PCT / IB2022 / 056646. Typically, SMA actuators use SMA wires. SMA wires are beneficial for use in mobile devices because they are inexpensive, lightweight, compact and can be used for low-power, low-noise, compact actuators. Typically, SMA wires are operable under load for e.g. twenty-five thousand (25,000) cycles, which is not beneficial because operation beyond one hundred thousand (100,000) cycles can be mandatory when used in mobile devices.

[0019] It is beneficial to have a wide camera lens design that supports a PO wide camera that includes a large image sensor, e.g. 1 / 1.33” or larger, i.e. with SD ≥ 12 mm.

[0020] It is beneficial to have a fully passive POC, i.e. a relatively slim camera, that is included in a mobile device, that still provides a large zoom effect or uses a large image sensor, and that does not require an active actuation when switching from the PO state to the collapsed state, and vice versa. Such a fully passive POC is disclosed here.

[0021] It is beneficial to have an SMA actuator that is operable for a relatively large number of cycles (e.g. up to 100,000 cycles) and that is used in a mobile device. Such an SMA actuator camera is disclosed here. SUMMARY

[0022] In various examples, a lens system for a compact digital camera is provided, the lens system comprising: an image sensor with a sensor diagonal SD; and a lens with a field of view FOV and with N = 9 lens elements L1-L9 arranged along a lens optical axis OA from L1 on the object side towards the image side, each lens element Li having a corresponding focal length f with a magnitude of |f i |, where 1 ≤ i ≤ N, the lens elements being divided into two lens groups G1 and G2 separated by a large gap BG, the lens having a total track length TTL < 20 mm in the PO state and a contracted total track length c-TTL in the contracted state, where the lens system is configured to switch from the PO state to the contracted state by contracting BG to a contracted large gap c-BG, and vice versa, where BG > 0.2x TTL, where SD ≥ 12 mm, and where the ratio c-TTL / SD ≤ 0.65.

[0023] In various examples, a lens system for a compact digital camera is provided, the lens system having a PO state and a contracted state, and comprising: an image sensor having a sensor diagonal SD; and a lens having N lens elements L1-L N , the lens elements being arranged along the lens optical axis OA starting from L1 from the object side towards the image side, each lens element L i having a corresponding clear aperture diameter DA Li , where 1 ≤ i ≤ N, and having a field of view FOV and an f-number (f / #), a lens thickness T Lens , a back focal length BFL, an effective focal length EFL, and a total track length TTL < 20 mm in the PO state, where the lens system is configured to switch from the PO state to the contracted state by contracting BFL to a contracted back focal length c-BFL, and vice versa, where BFL > 0.2x TTL, where SD ≥ 15 mm, and where the ratio c-TTL / SD < 0.7.

[0024] In various examples, a foldable mobile device including a passive pop-up camera (POC) is provided, the passive POC comprising: a pop-up lens; an image sensor; and a passive pop-up (PO) actuator, where the foldable mobile device is deployable by a deployment movement and foldable by a folding movement, both movements being performed by a user, where the POC has a PO state and a contracted state, in the PO state the POC is operable and has a total track length TTL, and in the contracted state the POC has a contracted c-TTL < TTL, where the passive PO actuator is operable to switch the passive POC from the PO state to the contracted state using the folding movement, and where the passive PO actuator is operable to switch the passive POC from the contracted state to the PO state using the deployment movement.

[0025] ​​In various examples, a foldable mobile device including a passive fold-out pop camera (POC) is provided, the passive fold-out POC including: a lens; a mirror; an image sensor; a passive pop actuator; and a camera housing, wherein the foldable mobile device is expandable by an expansion movement and foldable by a folding movement, both movements performed by a user, wherein the lens is located on an object side of the mirror, wherein the camera housing has a module region having a module height H M , and a shoulder region having a shoulder height H S <H M , wherein the passive fold-out POC has a PO state in which the passive fold-out POC is active and has a module height H M , and a collapsed state in which the passive fold-out POC has a collapsed module height c-H M <H M , wherein the passive PO actuator is operable to switch the passive fold-out POC from the PO state to the collapsed state using the folding movement, and wherein the passive PO actuator is operable to switch the passive fold-out POC from the collapsed state to the PO state using the expansion movement.

[0026] In various examples, a shape memory alloy (SMA) actuator included in a camera is provided, the SMA actuator including: a plurality of P≥2 SMA wires; and a moving element operable to actuate a component included in the camera, wherein the camera is included in a mobile electronic device, wherein each SMA wire of the plurality of P SMA wires is operable over M cycles, wherein the plurality of P SMA wires are guided by the moving element, wherein a force to actuate the component included in the camera is provided by one SMA wire of the plurality of P SMA wires, and wherein the P SMA wires are used sequentially such that the SMA actuator is operable over an expanded number of PXM cycles. BRIEF DESCRIPTION OF DRAWINGS

[0027] Non-limiting examples of examples disclosed herein are described below with reference to the accompanying drawings appended hereto, listed after this paragraph. Identical structures, elements or parts that appear in more than one figure are generally labeled with like numerals in all figures in which they appear. If identical elements are shown in only one of multiple figures but are numbered, it is assumed that they have the same numbering in all figures in which they appear. The drawings and descriptions are intended to illustrate and clarify examples disclosed herein, and should not be considered to be limiting in any way. In the drawings:

[0028] FIG. 1ADefinitions of various entities such as TTL and EFL are shown schematically;

[0029] FIG. 1B Definitions of FOV, EFL and S for thin lens approximation or equivalence are shown;

[0030] FIG. 1C schematically illustrates a mobile device including a known PO camera (“POC”) in a first state (“collapsed state”);

[0031] FIG. 1D schematically illustrates the mobile device of FIG. 1C in a second (popped out) state;

[0032] FIG. 2A schematically illustrates a PO optical lens system disclosed herein in a PO state focused to infinity;

[0033] FIG. 2B schematically illustrates the PO system of FIG. 2A in a collapsed state;

[0034] FIG. 2C illustrates an example of a 1G PO optical lens system including a PO lens disclosed herein in a PO state;

[0035] FIG. 2D illustrates the PO system of FIG. 2C in a collapsed state;

[0036] FIG. 3 An example of a 2G PO optical lens system disclosed herein is shown.

[0037] FIG. 4 Another example of a 2G PO optical lens system disclosed herein is shown.

[0038] FIG. 5 An example of a 1G PO optical lens system disclosed herein is shown.

[0039] FIG. 6 Yet another example of a 2G PO optical lens system disclosed herein is shown.

[0040] FIG. 7 Another example of a 1G PO optical lens system disclosed herein is shown.

[0041] FIG. 8A A foldable phone including a passive PO camera as disclosed herein in a partially deployed state is shown in cross-sectional side view.

[0042] FIG. 8B A foldable phone of FIG. 8A in a folded state is shown in cross-sectional side view.

[0043] FIG. 8C An enlarged section of a foldable phone of FIG. 8A in a folded state is shown in cross-sectional side view.

[0044] FIG. 9A Another foldable phone including a passive PO camera as disclosed herein in a partially extended state is shown in cross-sectional side view.

[0045] FIG. 9B A foldable phone of FIG. 9A in a folded state is shown in cross-sectional side view.

[0046] FIG. 9C An enlarged section of a foldable phone of FIG. 9A in a folded state is shown in cross-sectional side view.

[0047] FIG. 10A Another foldable phone including a passive PO camera as disclosed herein in a partially extended state is shown in cross-sectional side view.

[0048] FIG. 10B A foldable phone of FIG. 10A in a folded state is shown in cross-sectional side view.

[0049] FIG. 11A Another foldable phone including a passive PO camera as disclosed herein in a partially extended state is shown in cross-sectional side view.

[0050] FIG. 11B A foldable phone of FIG. 11A in a folded state is shown in cross-sectional side view.

[0051] FIG. 12 A shape memory alloy actuator as disclosed herein is shown in perspective view. DETAILED DESCRIPTION

[0052] FIG. 2A shows a known art example of a “2-group” (or “2G”) pop-out (“PO”) optical lens system 200 including a PO lens 202 and an image sensor 204. The PO optical lens system 200 is shown in a PO or extended state (and focused to infinity). The PO lens 202 is split into two lens groups separated by a large gap (BG), a first object-side lens group (“Gl”) and a second sensor-side lens group (“G2”). The thickness of Gl is denoted by T G1indication. The lens 202 includes a plurality of N lens elements Li (where "i" is an integer between 1 and N, and where N can be, for example, between 5 and 10). Li is the lens element closest to the object side, while 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. Each lens element Li includes a respective front surface S2i-1 (index "2i-1" is the number of the front surface) and a respective back surface S2i (index "2i" is the number of the back surface). This numbering convention is used throughout the specification. Alternatively, as done throughout this specification, the lens surfaces are labeled as "Sk", k running from 1 to 2N. The front and back surfaces can in some cases be aspherical. This is not a limitation, however.

[0053] As used herein, the term "front surface" of each lens element refers to the surface of the lens element closer to the entrance of the camera (the camera object side), while the term "back surface" refers to the surface of the lens element closer to the image sensor (the camera image side).

[0054] Each lens group includes one or more lens elements Li. G1 can include greater than or equal to 5 elements and G2 can include 1-2 elements. G2 can function as a field lens as known in the art.

[0055] Figure 2B shows the 2G PO optical lens system 200 in a collapsed state. The large gap BG is collapsed into a collapsed BG (labeled "c-BG"), i.e., the distance between G1 and G2 is reduced, resulting in a collapsed TTL ("c-TTL"). The c-BG can be in the range of 0.1 mm - 5 mm. Only the BG is changed. Other distances in the PO optical lens system 200 (e.g., the BFL or the distances between the lens elements included in G1 and G2, respectively) are not changed.

[0056] Figure 2C shows another example of a 1G PO optical lens system 250 including a PO lens 252 having a lens thickness T Lens of 0.5 mm and an image sensor 254 in a PO state as disclosed herein. The PO lens 252 has a lens optical axis as shown. The 1G PO optical lens system 250 is shown in a PO or extended state (and focused to infinity). The lens 252 includes a plurality of N lens elements. The BFL is shown.

[0057] Figure 2D shows the 1G PO optical lens system 250 in a collapsed state. The BFL is collapsed into a collapsed BFL (labeled "c-BFL"), i.e., the distance between the lens 252 and the image sensor 254 is reduced, resulting in a collapsed TTL ("c-TTL"). The lower limit of the c-TTL is set by the thickness ("T Lens") is given, i.e. c-TTL > T Lens . In fact, c-TTL = T Lens + c-BFL, where c-BFL = 0.2 mm - 1.5 mm or more. This means that c-TTL = T Lens + 0.2 mm to T Lens + 1.5 mm or more.

[0058] 2G PO optical lens system 200 is operable to be used in a PO camera. The resulting POC is operable as a camera only in the PO state. In the collapsed state, the POC is not operable as a camera, i.e. it is inactive.

[0059] 1G PO optical lens system 250 is a “1 group” (or “1G”) PO optical lens system, i.e. the lens 252 moves as one unit, which means that the distance between the lens elements included in the lens 252 does not change when switching from the PO state to the collapsed state, while only the BFL changes. The 2G PO optical lens system 200 and the 1G PO optical lens system 250 can (or are operable to be) included in a POC. To perform optical image stabilization (OIS), the POC can use several methods known in the art. Such methods can be “lens shift OIS”, in which the lens moves relative to the image sensor and the camera host mobile device for OIS, or “sensor shift OIS”, in which the image sensor moves relative to the lens and the camera host mobile device for OIS.

[0060] All the PO optical lens systems disclosed herein can be used in the POC examples described in the commonly owned PCT patent application PCT / IB2020 / 058697.

[0061] All the PO optical lens systems disclosed below are shown in the PO state, in which the POC including the optical lens system is operable.

[0062] In the collapsed state, all the 2G PO optical lens system examples have a c-BG of 0.2 mm - 4.0 mm. A small c-BG is beneficial to achieve a slim camera module that can be integrated in a slim mobile device such as a smartphone. The c-TTL can be in the range of 9.94 mm to 13.9 mm. In the collapsed state, all the 1G PO optical lens system examples have a c-BFL of 0.2 mm - 3.0 mm. A small c-BFL is beneficial to achieve a slim camera module. The c-TTL can be in the range of 9.26 mm to 13.22 mm. For the sake of clarity, all the lens systems disclosed here can be beneficially included in a mobile device such as a smartphone.

[0063] FIG. 3An example of a 2G PO lens system disclosed herein and numbered 300 is shown. The lens system 300 includes a PO lens 302 split into two lens groups G1 and G2 and having a lens optical axis 308, an image sensor 304, and optional optical elements 306. The optical elements 306 can be, for example, an infrared (IR) filter, and / or a glass image sensor dust cover. The image sensor 304 can have an SD of 21.5 mm. G1 includes 7 lens elements (L1-L7), and G2 includes 2 lens elements (L8-L9). Light rays pass through the lens 302 and form an image on the image sensor 304. FIG. 3 Six fields are shown, each with 4 rays.

[0064] Detailed optical data and surface data for the PO lens 302 are given in Tables 1-2. Table 1 provides surface types, and Table 2 provides aspheric coefficients. The surface types are:

[0065] a) Plano: flat surface, no curvature.

[0066] b) Q Type 1 (QT1) surface sag formula:

[0067]

[0068] c) Even Asphere (ASP) surface sag formula:

[0069]

[0070] where {z, r} are standard cylindrical polar coordinates, c is the paraxial curvature of the surface, k is the conic parameter, r norm is half the clear aperture (CA) of the surface, A n is the aspheric coefficients shown in the lens data table. The z-axis is positive towards the image side. The value of CA is given in clear aperture radius (i.e., D / 2). The reference wavelength is 555.0 nm. Units are mm, except for the refractive index (“index”) and Abbe number (Abbe #). Each lens element Li has a respective focal length fi given in Table 1. FOV is given in half FOV (HFOV).

[0071] Table 1

[0072]

[0073] Table 2

[0074]

[0075]

[0076] Continuation of Table 2

[0077]

[0078]

[0079] The power sequence of the lens elements from LI to L9 is as follows: + - + - + - + - + - (positive-negative-positive-negative-negative-positive-negative-positive-negative), i.e., the PO lens 302 includes four positive lens elements and five negative lens elements. L8 and L9 each have a maximum SAG of 3.8 mm and 3.5 mm, respectively, as indicated by “Max_SAG L8 ” and “Max_SAG L9 ”, respectively.

[0080] LI is made of glass;

[0081] EFL G1 and EFL G2 have opposite signs but similar magnitudes, i.e., |EFL G1 | and |EFL G2 | differ from each other by less than 3%;

[0082] G1 is thicker than G2, G1 being about 4.5 times thicker than G2;

[0083] f9 and EFL G2 have the same sign and similar magnitudes, i.e., f9 and EFL G2 differ from each other by less than 4%;

[0084] f6 is the strongest lens element of the lens 306. f6 is stronger than the lens 306, f6 being more than 1.5 times the lens 306;

[0085] L4 and L5 are close to each other. AGT L4-L5 is less than 2% of TTL;

[0086] The ratio of cTTL to SD is between 0.46-0.64;

[0087] The ratio of BG to TTL is 0.33;

[0088] The ratio of BG to cTTL is between 0.35-0.49;

[0089] The ratio of cTTL to TTL is between 0.68-0.94;

[0090] The ratio of cTTL to EFL is between 0.86-1.19;

[0091] The maximum SAG (Max_SAG L8 ) of L8 is 5.25 times the thickness of L8; and

[0092] Max_SAG of L9 (Max_SAG L9 ) is 4.04 times the thickness of L9.

[0093] FIG. 4 Another example of a 2G PO optical lens system disclosed herein and numbered 400 is shown. The lens system 400 includes a PO lens 402 split into two lens groups G1 and G2 and having a lens optical axis 408, an image sensor 404, and optional optical elements 406. The image sensor 404 can have an SD of 21.5 mm. G1 includes 8 lens elements (L1-L8) and G2 includes 1 lens element (L9). The detailed optical data and surface data of the PO lens 402 are given in Tables 3-4. Table 3 provides the surface types and Table 4 provides the aspheric coefficients.

[0094] L1 and L6 are made of glass;

[0095] EFL G1 and EFL G2 have opposite signs but similar magnitudes, i.e., |EFL G1 | and |EFL G2 | differ from each other by less than 25%;

[0096] The center thickness of G1 is greater than the center thickness of G2, the center thickness of G1 being about 7 times the center thickness of G2;

[0097] f9 and EFL G2 have the same sign and similar magnitudes, i.e., f9 and EFL G2 differ from each other by less than 2%;

[0098] f6 is the strongest lens element of the lens 406. f6 is stronger than the lens 406, f6 being about 1.5 times the lens 406;

[0099] L5 and L6 are close to each other;

[0100] The ratio of cTTL to SD is between 0.49-0.65;

[0101] The ratio of BG to TTL is 0.27;

[0102] The ratio of BG to cTTL is between 0.27-0.36;

[0103] The ratio of cTTL to TTL is between 0.75-0.98;

[0104] The ratio of cTTL to EFL is between 0.92-1.21; and

[0105] The lens power sequence from L1 to L9 is positive-positive-positive-negative-negative-positive-positive-positive-negative, i.e., the PO lens 402 includes six positive lens elements and three negative lens elements.

[0106] Table 3

[0107]

[0108] Table 4

[0109]

[0110] Table 4 (continued)

[0111]

[0112]

[0113] FIG. 5 An example of a 1G PO optical lens system disclosed herein and numbered 500 is shown. The lens system 500 includes a PO lens 502 having a lens optical axis 508, an image sensor 504, and optional optical elements 506. The image sensor 504 can have an SD of 21.5 mm. The PO lens 502 includes 8 lens elements (L1-L8). Light rays pass through the lens 502 and form an image on the image sensor 504. The detailed optical data and surface data for the PO lens 502 are given in Tables 5-6. Table 5 provides the surface types and Table 6 provides the aspheric coefficients.

[0114] Table 5

[0115]

[0116] Table 6

[0117]

[0118]

[0119] Table 6 (continued)

[0120]

[0121]

[0122] FIG. 6Another example of a 2G PO optical lens system disclosed herein and numbered 600 is shown. The lens system 600 includes a PO lens 602 split into two lens groups G1 and G2 and having a lens optical axis 608, an image sensor 604, and optional optical elements 606. The image sensor 604 can have an SD of 21.5 mm. G1 includes 8 lens elements (L1-L8) and G2 includes 1 lens element (L9). The detailed optical data and surface data for the PO lens 602 are given in Tables 7-8. Table 7 provides the surface types and Table 8 provides the aspherical coefficients.

[0123] Table 7

[0124]

[0125] Table 8 Continuation of Table 8

[0126]

[0127]

[0128] Continuation of Table 8

[0129]

[0130] FIG. 7 An example of a 1G PO optical lens system disclosed herein and numbered 700 is shown. The lens system 700 includes a PO lens 702 having a lens optical axis 708, an image sensor 704, and optional optical elements 706. The image sensor 704 can have an SD of 21.5 mm. The PO lens 702 includes 6 lens elements (L1-L6). Light rays pass through the lens 702 and form an image on the image sensor 704. The detailed optical data and surface data for the PO lens 702 are given in Tables 9-10. Table 9 provides the surface types and Table 10 provides the aspherical coefficients.

[0131] In terms of the lens shape of L6, not the entire BFL can be shrunk, but only the BG from L6 to the nearest point of the image sensor 706 and the optical elements 706 is expanded, respectively.

[0132] Table 9

[0133]

[0134] Table 10

[0135]

[0136]

[0137] Table 10 continued

[0138]

[0139] Table 11 shows values and ranges for the optical lens systems 300, 400, 500, 600, and 700 disclosed herein.

[0140] - SD, TTL, c-TTL, BG, c-BG, BFL, c-BFL, EFL, EFL G1 , EFL G2 , T G1 , T G2 , T Lens ,

[0141] f5, f6, f9, AGT L4-L5 , Max_SAG in mm; half field of view (“HFOV”) in degrees, and f-number (“f / #”) in units of nothing.

[0142]

[0143] - Image sensor 304, image sensor 404, image sensor 504, and image sensor 604 can have an SD of 21.5 mm (“4 / 3” sensor or “1 / 0.8” sensor).

[0144] AGT L4-L5 represents the average thickness of the air gap between L4 and L5. Here, “average thickness” means the average of the distance between L4 and L5 considering all y values from 0 (i.e., from the optical axis, e.g., optical axis 308) to D / 2 (i.e., the highest lens clearance).

[0145] c-BG MIN and c-BG MAX represent the minimum and maximum values of the contracted BG, respectively. c-BG can have any value between c-BG MIN and c-BG MAX .

[0146] c-BFL MIN and c-BFL MAX represent the minimum and maximum values of the contracted BFL, respectively. c-BFL can have any value between c-BFL MIN and c-BFL MAX .

[0147] c-TTL MIN and c-TTL MAX represent the minimum and maximum values of the contracted TTL, respectively. c-TTL can have any value between c-TTL MIN and c-TTL​MAX Any value between.

[0148] T Lens T G1 and T G2 These represent the center thickness of the lens, or the center thicknesses of G1 and G2, respectively. The center thickness is measured at the optical axis of the lens.

[0149] f5, f6, and f9 refer to the focal lengths of L5, L6, and L9, respectively.

[0150] Table 11

[0151]

[0152]

[0153] FIG. 8A to FIG. 8B A foldable phone (“FP”) 800 including the internal passive POC 802 disclosed herein is illustrated exemplarily. “Internal” here means that the FOV 808 of the camera 802 is located on the same side of the FP 800 as its “main screen.” The main screen is the largest screen included in the FP 800 (i.e., having the largest screen area). The FP 800 includes a hinge axis 810 that connects a first wing 812 to a second wing 818, and the hinge axis 810 is operable to allow the FP 800 to be unfolded and folded. The hinge axis 810 is oriented perpendicular to the xy-plane. The first wing 812 includes a first outer (or world-facing) side 814 and a first inner (or user-facing) side 816. The second wing 818 includes a second outer side 820 and a second inner side 822. Typically, the main screen of the FP 800 extends over the first inner side 816 and the second inner side 822. When the FP 800 is unfolded, the main screen can be used as a whole, and the internal passive POC 802 is operable (or "active") as a user-facing (or "selfie") camera. In some examples, the first outer side 814 and / or the second outer side 820 also include a screen. When the FP 800 is folded, the aperture of the internal passive POC 802 is covered by the second wing 818. The internal passive POC 802 includes a passive POC actuator ( FIG. 8C It has a lens optical axis (“OA”) and a lens thickness T. L The PO lens 804 and the image sensor 806. The internal passive POC 802 is included in and surrounded by the camera module housing (or simply "camera housing") 809.

[0154] FIG. 8AThe FP 800 is shown in a partially deployed state, in which the passive POC 802 is in a PO state. In the PO state, the inner passive POC 802 has a TTL and is active as a camera, i.e., the PO lens 804 is operable to image a sharp (or clear) image of a scene onto the image sensor 806. In the PO state, the height (“H C ”) of the camera housing 809 is defined by the TTL and a mechanical “penalty” (“p”), H C = TTL + p, where p can be in the range of 0.5mm - 5mm. The low H C is beneficial for use in slim mobile devices such as smartphones. Here and hereafter, H C , TTL, and p are measured along the z-axis.

[0155] FIG. 8B The FP 800 is shown in a folded state. In the folded state, the inner passive POC 802 is in a collapsed state. In the collapsed state, the passive POC has a c-TTL < TTL and is not active as a camera. The deployment movement between the folded state FIG. 8B ) and the deployed state FIG. 8A ) is indicated by arrow 824. The folding movement between the partially deployed state FIG. 8A ) and the folded state FIG. 8B ) is indicated by arrow 826. The deployment movement and the folding movement are typically performed manually by a user. The height (“H”) of each of the first wing 812 and the second wing 818 is shown. The first wing 812 has a regular region with a height (“H”) and a bump region with a raised height H + B, where “B” is the bump height. The bump region extrudes from the first inner side 816. The inner passive POC 802 is integrated in the bump region, and the inner passive POC 802 receives light from a scene facing the first inner side 816. In the collapsed state, the camera housing 809 has a collapsed height (“c-HC”) < HC, which is defined by c-H C = c-TTL + p. The c-H C ≤ H, so that there is no camera bump in the collapsed state. In other examples, there can be a reduced camera bump in the collapsed state. “Reduced” here means that the camera bump has a lower B compared to the PO state. Here and hereafter, H, B, c-H C , and c-TTL are measured along the z-axis.

[0156] FIG. 8CAn enlarged section 830 is shown with FP 800 in the folded state and the internal passive POC 802 in the collapsed state. Section 830 shows a passive PO actuator 832 as disclosed herein. Passive PO actuator 832 includes a spring 834. At the upper end, spring 834 is fixedly attached to first outer side 814, or more generally, to a component included in first wing 812 that does not move relative to first wing 812. At the lower end, spring 834 is fixedly attached to the PO lens barrel that includes PO lens 804. In the collapsed state, spring 834 stores kinetic energy and is operable to provide a spring force as shown by arrow 836, i.e., spring 834 is loaded. When the user unfolds FP 800, spring 834 relaxes and the spring force actuates (or “pops out”) the internal passive POC 802, i.e., the internal passive POC 802 switches to the PO state. When the user folds FP 800, spring 834 is compressed and loaded, thereby the internal passive POC 802 is switched to the collapsed state. We note that when FP 800 is folded by the user, the passive POC 802 is simultaneously switched from the PO state to the collapsed state. When FP 800 is unfolded by the user, the passive POC 802 is simultaneously switched from the collapsed state to the PO state. No active actuation is required as is expected for mobile devices such as FPs.

[0157] In some examples, a mechanical spring can be used, as shown here. In other examples, a magnetic spring can be used. The magnetic spring can include a magnet and a magnetic yoke, or alternatively, two magnets. Such magnetic springs are described, for example, in commonly owned International Patent Application Nos. PCT / IB2022 / 052194 and PCT / IB2023 / 054411.

[0158] FIG. 9A to FIG. 9B An FP 900 is exemplarily shown that includes an external passive POC 902 as disclosed herein. Here, “external” means that the FOV 908 of passive POC 902 is on the opposite side of the main screen of FP 900. FP 900 includes all the components as described in FIG. 8A to FIG. 8B FIG. 9C , PO lens 904, and image sensor 906. External passive POC 902 is included in a camera housing 909.

[0159] FIG. 9A ​The FP 900 is shown in a partially unfolded state and the external passive POC 902 is in a PO state. The bulge region is extruded from the first outer side 814. The external passive POC 902 is integrated in the bulge region and receives light from the scene facing the first outer side 814.

[0160] FIG. 9B The FP 900 is shown in a folded state with the external passive POC in a collapsed state.

[0161] FIG. 9C An enlarged section 930 of the FP 900 in a folded state and the external passive POC 902 in a collapsed state is shown. The section 930 shows the passive POC actuator 932 as disclosed herein and including a magnetic spring 940. The magnetic spring 940 includes a first magnet 942 fixedly attached to a P0 lens barrel including the P0 lens 804 and a second magnet 944 fixedly attached to the second wing 818. The first magnet 942 and the second magnet 944 are selected and oriented such that they attract each other. In the collapsed state, the first magnet 942 and the second magnet 944 are in close proximity to each other, thereby storing magnetic energy, and the magnetic spring 940 is operable to provide a magnetic spring force as indicated by the arrow 946. The magnetic spring force causes the external passive POC 902 to collapse. When the user unfolds the FP 900, the magnetic spring 940 relaxes and does not provide the magnetic spring force. Another spring included in the external passive POC 902 can provide a spring force to pop out the external passive POC 902, i.e., the external passive POC 902 switches to the PO state. The first magnet 942 and the second magnet 944 are relatively far apart from each other. When the user folds the FP 900, the first magnet 942 and the second magnet 944 are again in close proximity to each other, and the external passive POC 902 switches to the collapsed state. We note that when the FP 900 is folded by the user, the external passive POC 902 is simultaneously switched from the PO state to the collapsed state. When the FP 900 is unfolded by the user, the external passive POC 902 is simultaneously switched from the collapsed state to the PO state. No active actuation is required as expected for mobile devices such as FPs.

[0162] FIG. 10A to FIG. 10B An FP 1000 is exemplarily shown including an external passive POC 1002 as disclosed herein. The FP 1000 includes all the components as described in the FIG. 8A to FIG. 8B

[0163] FIG. 10A ​The FP 1000 is shown in a partially unfolded state and the passive POC 1002 is in a PO state.

[0164] FIG. 10B The FP 1000 is shown in a folded state and the passive POC is in a collapsed state. The bulge region is extruded from the first outer side 814. The external passive POC 1002 is integrated in the bump region and receives light from the scene facing the first outer side 814. The PO actuator 1010 includes a plurality of O gears (here, O = 3), namely a first gear 1012, a second gear 1014, and a third gear 1016. The PO actuator 1010 is located at or near the hinge shaft 810. For example, the PO actuator 1010 can be located at a distance of up to 25 mm from the hinge shaft 810. In fact, the external passive POC 1002 is also located relatively close to the hinge shaft 810. For example, the POC 1002 can be located at a distance of up to 50 mm from the hinge shaft 810. The PO actuator 1010 uses movements such as an unfolding movement indicated by arrow 824 or a folding movement indicated by arrow 826 to switch the external passive POC 1002 from the PO state to the collapsed state, as indicated by arrow 1018, and vice versa. That is, the PO actuator 1010 converts the rotational unfolding or folding movement of the first wing 812 and the second wing 818 around the hinge shaft 810 to a linear movement along the z-axis of the PO lens barrel including the PO lens 804 and relative to the image sensor 806. We note that when the FP 1000 is folded by the user, the external passive POC 1002 is simultaneously switched from the PO state to the collapsed state. When the FP 1000 is unfolded by the user, the external passive POC 1002 is simultaneously switched from the collapsed state to the PO state. No active actuation is required as expected for mobile devices such as FPs.

[0165] FIG. 11A to FIG. 11B An exemplary FP 1100 including the external passive POC 1102 disclosed herein is shown. FIG. 11A The FP 1100 is shown in a partially unfolded state and the external passive POC 1102 is in a PO state. The FP 1100 includes as FIG. 8A to FIG. 8BAll components described in the middle except for a different passive POC. The external passive POC 1102 receives light from a scene facing the first external side 814. In the PO state, the external passive POC 1102 is operable as a folded camera as known in the art. The external passive POC 1102 includes a passive PO actuator (not shown), a lens 1104, a mirror 1108, an image sensor 1106, and is included in a camera housing 1109. The external passive POC 1102 is operable to receive light along a first optical path (“OP1”) parallel to the z-axis. The OA of the lens 1104 is parallel to OP1. In the PO state, the mirror 1108 is oriented at an angle of about 45 degrees with respect to the z-axis, such that the reflected light propagates towards the image sensor 1106 along a second optical path (“OP2”) parallel to the z-axis. The lens 1104 is located on the object side of the mirror 1108, which provides a relatively low f / # for a given camera height, which is beneficial for use in mobile devices such as FP. Such cameras are described, for example, in commonly owned International Patent Application No. PCT / IB2022 / 055745. In the PO state, the camera housing 1109 has a first elevated (“module”) region including the PO lens 1104 and the mirror 1108, and a second (“shoulder”) region including the image sensor 1106. The module region has a minimum module height (“MH L ”) defined by the height of the mirror 1108 and an air gap of about 0.1 mm - 2.5 mm between the PO lens 1104 and the mirror 1108. M The height (“H M ”) of the module region of the camera housing 1009 measured along the z-axis is defined by MH M and a mechanical “penalty” (“p”), H M = MH M + p, where p can be in the range of 0.5 mm - 5 mm. The shoulder region has a minimum shoulder height (“MH S ”) < MH M and is defined by the height of the image sensor 1106 measured along the z-axis. The height (“H S ”) of the shoulder region of the camera housing 1009 measured along the z-axis is defined by MH S and a mechanical “penalty” (“p”), H S = MH S + p, where p can be in the range of 0.5 mm - 5 mm. Low H M and low H S are beneficial for use in slim mobile devices such as smartphones. When H S < H MAt this time, the shoulder region can be integrated into a regular region with height H. Only the module region is integrated into the hump region. In other words, the external passive POC 1102 is only partially integrated in the hump region, which is beneficial for achieving a relatively small hump region. Here and in the following, the height, air gap, MH M , H M , MH S , H S , and p.

[0166] FIG. 11B The FP 1100 is shown in the folded state and the external passive POC 1102 is in the collapsed state. To switch from the PO state to the collapsed state, the PO lens 1104 moves linearly beyond the second wing 818. The mirror 1108 moves about 45 degrees in rotation about an axis perpendicular to OP1 and OP2, so that it forms an angle of about 0 degrees with the y-axis, in addition, it moves linearly towards the second wing 818. "About" means here a variation of e.g. ±10 degrees or ±5 degrees. The respective movements are performed so that MH M collapses into c-MH M < MH M , and H M collapses into c-H M < H M , c-H M is given by c-H M = c-MH M + p. c-H M ≤ H, so that no camera hump is needed in the collapsed state. MH S does not change. To provide actuation of the respective movements of the PO lens 1104 and the mirror 1108, the external passive POC 1102 can comprise a passive PO actuator, e.g. a passive PO actuator 932 FIG. 9C ) comprising a magnetic spring, or it can comprise a passive PO actuator, e.g. a passive PO actuator 1010 FIG. 10A to FIG. 10B ) comprising a plurality of gears.

[0167] FIG. 12An SMA actuator 1200 as disclosed herein is shown. The SMA actuator 1200 is operable for (or “within”) a relatively large number of cycles (see examples below) and for a camera of a mobile device such as a smartphone. The SMA actuator 1200 includes a moving element 1202 that is operable to move relative to a mobile device that includes the moving element 1202, for example to switch the POC from the PO state and the contracted state (and vice versa) for focusing a lens or for movement of a lens or image sensor for optical image stabilization (OIS). The moving element 1202 includes a plurality of P number of guides 1210 (here, P = 4), namely a first guide 1212, a second guide 1214, a third guide 1216, and a fourth guide 1218. The SMA actuator 1200 includes a plurality of P number of SMA wires 1220 (here, P = 4), namely a first SMA wire 1222, a second SMA wire 1224, a third SMA wire 1226, and a fourth SMA wire 1228. Each of the P number of SMA wires 1220 is located in and guided by one of the P number of guides 1210. A preload force is applied between the P number of SMA wires 1220 and the P number of guides 1210 such that the P number of SMA wires 1220 do not disengage (or “derail”) from the moving element 1202. The SMA actuator 1200 further includes a first plurality of P number of crimps 1230 and a second plurality of P number of crimps 1232. That is, in total, the SMA actuator 1200 includes 2P number of crimps. Each crimp included in the first plurality of P number of crimps 1230 and the second plurality of P number of crimps 1232 is fixedly attached to one end of each SMA wire included in the P number of SMA wires 1220, as shown. The crimps provide mechanical and electrical connections. In other examples, the plurality of P number of guides and the P number of SMA wires can include P = 2 to 25, respectively.

[0168] The movement of the moving element 1202 can be a rotational movement along a rotational axis 1204 that is parallel to the z-axis. The rotational axis 1204 can be located at the center of the moving element 1202. In other examples, the movement of the moving element 1202 can be a linear movement in the x-y plane, as indicated by arrow 1206. To actuate such linear or rotational movement, the SMA actuator 1200 is operable to drive current through one of the P SMA wires 1220. That is, only one of the P SMA wires 1220 is operated during actuation. In other words, the SMA actuator 1200 operates the P SMA wires 1220 sequentially. For example, only the first SMA wire 1222 is operated during a first time period, only the second SMA wire 1224 is operated during a second time period, only the third SMA wire 1226 is operated during a third time period, and only the fourth SMA wire 1228 is operated during a fourth time period. This is beneficial for scaling (or extending) the number of cycles the SMA actuator 1200 is operable for. For example, a single SMA wire can be operable for M cycles under load, but the specification for the SMA actuator can require operation for PxM cycles. By operating the P SMA wires sequentially as detailed above, the PxM cycle specification can be met. For example, a single SMA wire such as the first SMA wire 1222 can be operable for M = twenty-five thousand (25,000) cycles under load, but the specification for the SMA actuator 1200 can require operation for 4xM = one hundred thousand (100,000) cycles. By operating the four SMA wires 1220 sequentially as detailed above, the one hundred thousand (100,000) cycle specification can be met. In this example, the relatively large number of cycles is one hundred thousand (100,000) cycles. In other examples, the relatively large number of cycles can be in the range of five thousand (5,000) cycles to five hundred thousand (500,000) cycles.

[0169] While the disclosure has been described in terms of certain examples and generally associated methods, alterations and permutations of the examples and methods will be apparent to those skilled in the art. The disclosure should not be construed as limited to the particular examples described, but rather should be understood to cover all modifications, equivalents, and alternatives falling within the scope of the appended claims.

[0170] It will be appreciated that certain features of the presently disclosed subject matter, which have been described in the context of separate examples, can also be provided in combination in a single example. Conversely, various features of the presently disclosed subject matter, which have been described in the context of a single example, can also be provided separately or in any appropriate

[0171] The use of the expression "and / or" between the last two members of a list of options for selection indicates that selection of one or more of the listed options is appropriate and can be made unless otherwise indicated.

[0172] It should be understood that where a claim or specification refers to “a” or “an” element, such reference is not to be construed as there being only one of such element.

[0173] All patents and patent applications mentioned in this specification are herein incorporated by reference in their entirety for the disclosure specifically identified as incorporated by reference. In the event of a conflict between the disclosure of this specification and the disclosure of a patent or patent application incorporated by reference, the disclosure of the latter shall control. 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 to the present disclosure.

Claims

1. A lens system for a compact digital camera, the lens system having an ejected state and a retracted state, and comprising: an image sensor having a sensor diagonal SD; and lens having N lens elements L1-L N , the lens elements L1-L N arranged along a lens optical axis OA starting with L1 from the object side towards the image side, each lens element L i having a respective clear aperture diameter DA Li , with 1≤i≤N, and having a field of view FOV in an uncollapsed state and having an f-number (f / #), a lens thickness T Lens , a back focal length BFL, an effective focal length EFL and a total track length TTL < 15 mm, wherein the lens system is configured to switch from an uncollapsed state to a collapsed state by collapsing the BFL into a collapsed back focal length c-BFL, and vice versa, wherein BFL > 0.2 x TTL, wherein SD≥12 mm, wherein the ratio c-TTL / SD < 0.8, and wherein f / #≤1.

6.

2. The lens system of claim 1, wherein N = 6.

3. The lens system of claim 1, wherein FOV > 70 degrees.

4. The lens system of claim 1, wherein FOV > 75 degrees.

5. The lens system of claim 1, wherein c-TTL / SD < 0.

75.

6. The lens system of claim 1, wherein c-TTL / SD < 0.

7.

7. The lens system of claim 1, wherein c-TTL / TTL < 0.

8.

8. The lens system of claim 1, wherein BFL > 0.3 x TTL.

9. The lens system of claim 1, wherein BFL > 0.35 x TTL.

10. The lens system of claim 1, wherein f / # < 1.

5.

11. The lens system of claim 1, wherein f / # < 1.

4.

12. The lens system of claim 1, wherein SD > 13 mm.

13. The lens system of claim 1, wherein SD is in the range of 13 mm to 15 mm.

14. The lens system of claim 13, wherein the EFL is in the range of 8 mm to 9.5 mm.

15. The lens system of claim 14, wherein the TTL is in the range of 13 mm to 14 mm.

16. The lens system of claim 2, wherein the sequence of lens powers from LI to L6 is negative-positive-negative-positive-negative-positive.

17. The lens system of any of claims 1-16, wherein the lens system is included in an ejected camera, and wherein the ejected camera is included in a mobile device.

18. The lens system of claim 17, wherein the mobile device is a smartphone.

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