Compact mobile folded cameras with optical image stabilization

Abstract

Disclosed is a folded camera including a lens, an optical path folding element (OPFE) that folds first and second optical axes, an image sensor, and an OIS actuator. The actuator rotates the lens and OPFE in combination by a first angle and rotates the image sensor by a second angle, the angles having a predetermined relation selected for the design for first axis OIS. Also disclosed is a lens actuator including a lens carrier translatable along a lens optical axis, a housing, a coil fixed to the housing, a magnet on the lens carrier interacting with the coil to translate the lens carrier, and a ferromagnetic preload yoke fixed to the housing and laterally disposed so no yoke is below the lens carrier along a height axis, the yoke magnetically interacting with the magnet to bias the lens carrier toward a guide.

Description

[0001] COMPACT MOBILE FOLDED CAMERAS WITH OPTICAL IMAGE STABILIZATION FIELD

[0002] The presently disclosed subject matter is generally related to the field of digital cameras, and more particularly to compact digital cameras for portable electronic devices.

[0003] BACKGROUND

[0004] Multi-aperture cameras (also referred to as multi -cameras, including dual-cameras) are commonly used in portable electronic devices such as smartphones and tablets. A multi -camera system typically includes a wide field-of-view camera having an approximately 20 mm to 35 mm, or 35 mm-equivalent focal length, and at least one additional camera, for example a telephoto camera having a narrower field of view and a longer 35 mm-equivalent focal length, and / or an ultra-wide camera having a wider field of view and an approximately 9 mm to 18 mm 35 mm-equivalent focal length.

[0005] Folded cameras are also used in mobile devices. In a folded camera, an optical path folding element (OPFE), such as a prism or mirror, may be used to fold a first optical path to a second optical path between a lens and an image sensor.

[0006] Optical image stabilization (OIS) is widely implemented in mobile devices. In OIS, one or more camera components are moved relative to each other to reduce image blur associated with undesired motion of the device. For compact implementations, it is desirable to provide OIS approaches that limit increases in camera height associated with the OIS mechanism. Such approaches may be referred to as slim OIS.

[0007] There remains a need for slim OIS approaches suitable for folded camera architectures, including ALOP folded cameras, and for compact camera actuator configurations that reduce complexity and component count while meeting mechanical and optical performance requirements.

[0008] GENERAL DESCRIPTION

[0009] Folded camera modules can provide increased effective focal length (EFL) within the limited thickness available in portable electronic devices. In this disclosure, EFL of a lens or lens assembly refers to a distance between a rear principal point P' and a rear focal point F'. In such modules, an optical path folding element (OPFE), such as a prism or mirror, folds a firstoptical path to a second optical path between the lens and an image sensor. While folded architectures are attractive for compact implementations, they can make optical image stabilization difficult to implement without increasing module thickness or complicating the mechanical structure. Accordingly, there remains a need for stabilization approaches that are compatible with folded optical layouts and that support compact packaging.

[0010] In one aspect, the present disclosure relates to optical image stabilization in a folded camera by coordinated angular adjustment of multiple camera elements. During stabilization, the lens and the optical path folding element are rotated in a coordinated manner about a selected pivot, while the image sensor is rotated about another pivot. The angular relationship between the rotation of the lens side and the rotation of the sensor side is selected based on the optical configuration and need not be limited to a strictly identical rotation. In some examples, the angular relationship is selected so that the stabilized image remains within an acceptable focus tolerance at the sensor plane, for example within a depth of focus of the optical system.

[0011] The disclosed stabilization approach can be applied to folded layouts in which the folded optical paths are perpendicular, as well as to layouts in which the folded optical paths define an angle other than a right angle. The geometry of the pivot locations and the respective rotation axes can be selected to match the optical design. In some examples, the pivot for rotating the lens and the folding element may be located at or near an intersection of the folded optical paths, and the pivot for rotating the image sensor may be located at or near a center position of the image sensor. These and other geometrical configurations can be used to achieve stable imaging while maintaining a compact module.

[0012] The present disclosure also contemplates stabilization in more than one direction. In addition to stabilization by angular adjustment within a plane associated with the folded optical paths, stabilization in a second direction can be provided. The second direction may be perpendicular to the plane defined by the folded optical paths. In some examples, stabilization in the second direction may be achieved by linear motion of one or more optical elements, and in other examples it may be achieved by rotation about a second rotation axis. Variations combining such approaches can also be used.

[0013] In another aspect, the present disclosure relates to actuator configurations for folded camera modules, including actuator structures that support focusing while reducing component count and stack height. In compact camera actuators, a lens carrier is typically guided relative to a housing and is translated along a lens optical axis. A preload may be used to bias the lens carrier toward a guiding surface or guiding mechanism, for example to maintain engagement with guide elements during motion and shock. Conventional preload implementations may addparts and increase thickness. The present disclosure provides actuator concepts in which a ferromagnetic yoke is positioned laterally relative to the lens carrier and is arranged to interact magnetically with a magnet used for actuation, thereby generating a preload force without requiring a separate preload magnet. In preferred implementations, the yoke is arranged such that no yoke portion is positioned below the lens carrier along a height axis perpendicular to the lens optical axis, which can support reduced module thickness.

[0014] In some implementations, the yoke and the coil may be supported by a printed circuit board, including a flex printed circuit board, and the actuator may include one or more voice coil motors. In configurations with multiple motors, multiple yokes may be provided, for example on opposite lateral sides of the lens carrier, to balance lateral force components while providing the desired preload toward the guiding mechanism. These and other arrangements described herein can reduce weight and complexity, support compact packaging, and provide stable mechanical behavior suitable for folded camera modules used in portable electronic devices.

[0015] According to a first broad aspect, the present disclosure provides a folded camera, comprising: a lens; an optical path folding element (OPFE) configured to fold a first optical path OP 1 to a second optical path OP2; an image sensor; and an optical image stabilization (OIS) actuator, wherein the OIS actuator provides for optical image stabilization about a first stabilization axis and is configured to rotate the lens and the OPFE in combination about a selected pivot by a first angle and rotate the image sensor about a second pivot by a second angle, and wherein the first and second angles have a predetermined relation between them.

[0016] According to some embodiments, the first and second angles are equal up to an angular variation of 10% of the first angle.

[0017] According to some embodiments, the lens is located at an object side of the OPFE. According to some embodiments, the lens is located at an image side of the OPFE.

[0018] According to some embodiments, a pivot point for rotating the lens and the OPFE in combination is located at an intersection of the first optical path and the second optical path.

[0019] According to some embodiments, the image sensor has a center position, and a pivot point for rotating the image sensor is located at the center position of the image sensor.

[0020] According to some embodiments, the OPFE is a prism.

[0021] According to some embodiments, the OIS actuator is further configured to provide OIS in a second direction perpendicular to a plane defined by OP1 and OP2.According to some embodiments, the OIS actuator is further operational to linearly move the lens along an axis perpendicular to both OP1 and OP2 by a selected amount to provide OIS in the second direction.

[0022] According to some embodiments, the OIS actuator is further operational to rotate the lens and the OPFE by a selected angle y about a second rotation axis parallel to OP2 to provide OIS in the second direction.

[0023] According to some embodiments, the OIS actuator further comprises a second actuator operable for rotation about the second rotation axis, the second rotation axis being parallel to OP2, and the OIS actuator is operational to rotate the lens, the OPFE, and the image sensor together by another angle y about the second rotation axis.

[0024] According to some embodiments, OP1 and OP2 are perpendicular to each other. According to some embodiments, an angle between OP1 and OP2 is smaller than 90 degrees.

[0025] According to some embodiments, the first angle is in a range of 0 to 5 degrees. According to some embodiments, the first angle is in a range of 0.25 to 2.5 degrees. According to some embodiments, the first angle is in a range of 0.25 to 1.5 degrees.

[0026] According to some embodiments, the image sensor has a full diagonal SD, and SD is in a range of 5 mm to 20 mm. According to some embodiments, SD is at most 12.5 mm.

[0027] According to some embodiments, an f-number (f / #) of the camera is in a range of 1.5 < f / # < 3 (i.e. between 1.5 and 3). According to some embodiments, f / # is in a range of 2 < f / # < 2.75 (i.e. between 2 and 2.75). In this connection The f-number (f / #) of a lens or lens system is defined as the ratio of the effective focal length (EFL) to the entrance pupil diameter (DA), namely f / # = EFL / DA, where EFL is the effective focal length and DA is the entrance pupil diameter (also referred to as the aperture diameter in many contexts).

[0028] According to some embodiments, the predetermined relation is selected such that an image formed on the image sensor remains within a depth of focus of the lens.

[0029] According to some embodiments, a mobile device comprises the folded camera as described herein. According to some embodiments, the mobile device is a smartphone.

[0030] According to a second broad aspect, the present disclosure provides a lens actuator for a folded camera module, comprising: a lens carrier configured to carry at least one lens and to be translatable along a lens optical axis; a housing; a magnet coupled to the lens carrier; a coil coupled to the housing and arranged to interact with the magnet to generate an actuation force for translating the lens carrier along the lens optical axis; and a ferromagnetic preload yoke fixed relative to the housing, wherein the preload yoke is arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface orguiding mechanism of the actuator, wherein the folded camera module is operational to capture light received from a scene along a first direction, and wherein the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis parallel to the first direction.

[0031] According to some embodiments, the coil and the magnet form a voice coil motor (VCM) configured to translate the lens carrier along the lens optical axis, and the magnet is a VCM magnet of the voice coil motor.

[0032] According to some embodiments, the lens actuator is free of a dedicated preload magnet distinct from the magnet coupled to the lens carrier.

[0033] According to some embodiments, translation of the lens carrier translates the lens along the lens optical axis.

[0034] According to some embodiments, the preload yoke is disposed on a first lateral side of the lens carrier, and no preload yoke is disposed on a second lateral side of the lens carrier opposite the first lateral side.

[0035] According to some embodiments, the lens actuator comprises a first voice coil motor (VCM) and a second voice coil motor (VCM), each VCM comprising a respective coil and a respective magnet, and the lens actuator comprises a first preload yoke and a second preload yoke.

[0036] According to some embodiments, the first preload yoke is disposed on a first lateral side of the lens carrier and the second preload yoke is disposed on a second lateral side of the lens carrier opposite the first lateral side.

[0037] According to some embodiments, the first preload yoke is arranged to magnetically interact with a magnet of the first VCM to generate a first preload force, and the second preload yoke is arranged to magnetically interact with a magnet of the second VCM to generate a second preload force.

[0038] According to some embodiments, the height axis is perpendicular to the lens optical axis. According to some embodiments, the lens carrier is translatable along the lens optical axis along a focusing stroke of 0.5 mm to 5 mm.

[0039] According to some embodiments, a height of the lens actuator measured along a height axis perpendicular to the lens optical axis is in the range of 4 mm to 13 mm. According to some embodiments, the height is in the range of 4 mm to 11 mm. According to some embodiments, the height is in the range of 4 mm to 9 mm.

[0040] According to some embodiments, at least one lens comprises a lens arrangement having an effective focal length EFL in a range of 10 mm < EFL < 40 mm.According to some embodiments, the lens actuator is included in a folded camera module, wherein the folded camera module comprises an optical path folding element (OPFE) for folding a first optical path (OP1) to a second optical path (OP2), and OP2 is parallel to the lens optical axis.

[0041] According to a third broad aspect, the present disclosure provides a lens actuator for use in a folded camera module, comprising: a lens arrangement comprising N lens elements and having a lens optical axis, the lens arrangement being mounted on a lens carrier; a printed circuit board (PCB); at least one voice coil motor (VCM) comprising at least one coil and at least one magnet; and at least one ferromagnetic preload yoke, wherein the lens actuator is operational to actuate the lens carrier along the lens optical axis for focusing utilizing actuation force from the at least one VCM, wherein the PCB carries the at least one coil and the at least one preload yoke, and wherein the at least one magnet and the at least one preload yoke are operational to provide a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator.

[0042] According to a fourth broad aspect, the present disclosure provides a folded camera, comprising: a lens; an optical path folding element (OPFE) configured to fold a first optical path OP1 to a second optical path OP2; an image sensor; and an optical image stabilization (OIS) actuator, wherein the OIS actuator is configured, for optical image stabilization about a first stabilization axis, to rotate the lens and the OPFE in combination about a selected pivot by a first angle, and to rotate the image sensor about a second pivot by a second angle, and wherein the first and second angles have a predetermined relation between them.

[0043] According to a fifth broad aspect, the present disclosure provides a folded camera, comprising: a lens; an optical path folding element (OPFE) configured to fold a first optical path OP1 to a second optical path OP2; an image sensor; and an optical image stabilization (OIS) actuator, wherein the OIS actuator is configured, for optical image stabilization about a first stabilization axis, to rotate the lens and the OPFE in combination about a selected pivot by a first angle, and to rotate the image sensor about a second pivot by a second angle, wherein the first and second angles have a predetermined relation between them, and wherein the predetermined relation is selected such that an image formed on the image sensor remains within a depth of focus of the lens.

[0044] According to a sixth broad aspect, the present disclosure provides a folded camera module, comprising: an optical path folding element (OPFE) configured to fold a first optical path (OP1) to a second optical path (OP2); and a lens actuator, comprising: a lens carrier configured to carry at least one lens and to be translatable along a lens optical axis; a housing;a magnet coupled to the lens carrier; a coil coupled to the housing and arranged to interact with the magnet to generate an actuation force for translating the lens carrier along the lens optical axis; and a ferromagnetic preload yoke fixed relative to the housing, wherein the preload yoke is arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator, and wherein the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis perpendicular to the lens optical axis, wherein OP2 is parallel to the lens optical axis.

[0045] According to some embodiments, the lens actuator is free of a dedicated preload magnet distinct from the magnet coupled to the lens carrier.

[0046] According to a seventh broad aspect, the present disclosure provides an electronic device, comprising: a folded camera comprising a lens, an optical path folding element (OPFE) configured to fold a first optical path OP1 to a second optical path OP2, an image sensor, and an optical image stabilization (OIS) actuator, wherein the OIS actuator is configured, for optical image stabilization about a first stabilization axis, to rotate the lens and the OPFE in combination about a selected pivot by a first angle, and to rotate the image sensor about a second pivot by a second angle, and wherein the first and second angles have a predetermined relation between them.

[0047] According to an eighth broad aspect, the present disclosure provides an electronic device, comprising: a folded camera module comprising an optical path folding element (OPFE) configured to fold a first optical path (OP1) to a second optical path (OP2); and a lens actuator comprising: a lens carrier configured to carry at least one lens and to be translatable along a lens optical axis; a housing; a magnet coupled to the lens carrier; a coil coupled to the housing and arranged to interact with the magnet to generate an actuation force for translating the lens carrier along the lens optical axis; and a ferromagnetic preload yoke fixed relative to the housing, wherein the preload yoke is arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator, and wherein the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis perpendicular to the lens optical axis.

[0048] According to a ninth broad aspect, the present disclosure provides an electronic device, comprising: a folded camera module; and a lens actuator for use in the folded camera module, the lens actuator comprising: a lens arrangement comprising N lens elements and having a lens optical axis, a lens height measured along a height axis perpendicular to the lens optical axis,and the lens arrangement being mounted on a lens carrier; a printed circuit board (PCB); at least one voice coil motor (VCM) comprising at least one coil and at least one magnet; and at least one ferromagnetic preload yoke, wherein the lens actuator is operational to actuate the lens carrier along the lens optical axis for focusing utilizing actuation force from the at least one VCM, wherein the PCB carries the at least one coil and the at least one preload yoke, and wherein the at least one magnet and the at least one preload yoke are operational to provide a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator.

[0049] BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Non-limiting examples of embodiments disclosed herein are described below with reference to the accompanying figures. The figures and corresponding descriptions are provided to illustrate and clarify example embodiments and are not intended to be limiting.

[0051] Figs. 1A to ID illustrate folded camera configurations as known in the art, wherein Fig.

[0052] 1A exemplifies a dual-camera arrangement, Fig. IB exemplifies a folded camera arrangement, Fig. 1C exemplifies a lens translating actuator, and Fig. ID exemplifies a preload arrangement for a lens actuator;

[0053] Figs. 2A and 2B illustrate an all-lens-on-prism folded camera implementing optical image stabilization (OIS) according to some embodiments, wherein Fig. 2A shows a center OIS position and Fig. 2B shows a non-center OIS position;

[0054] Figs. 3A and 3B illustrate another folded camera implementing OIS according to some embodiments, wherein Fig. 3A shows a center OIS position and Fig. 3B shows a non-center OIS position;

[0055] Figs. 4A and 4B illustrate a folded camera in which a lens is located at an image side of an optical path folding element and implementing OIS according to some embodiments, wherein Fig. 4A shows a center OIS position and Fig. 4B shows a non-center OIS position;

[0056] Fig. 5 schematically illustrates a mobile device including a folded camera operational to perform OIS according to some embodiments;

[0057] Figs.6A to 6D illustrate lens actuator configurations implementing preload arrangements according to some embodiments, including configurations with one preload yoke and with two preload yokes;

[0058] Figs. 7A to 7D illustrate an example lens actuator assembly according to some embodiments, wherein Figs. 7A and 7B show exploded views and Figs. 7C and 7D showassembled views; and

[0059] Fig. 8 schematically illustrates an electronic device including a folded camera module configured to perform optical image stabilization, and optionally including a lens actuator preload arrangement as described herein.

[0060] DETAILED DESCRIPTION

[0061] In the following, numerous specific details are set forth to provide a thorough understanding of the disclosed subject matter. However, persons skilled in the art will understand that the disclosed subject matter may be practiced without these specific details. In other instances, well known methods and features are not described in detail so as not to obscure the disclosed subject matter.

[0062] Fig. 1A illustrates a known dual camera system 150 including a folded telephoto camera 100 and a wide camera 130 (which may also be referred to as an upright camera). Folded telephoto camera 100 includes an optical path folding element (OPFE) 102, a lens included in a lens barrel 110, and an image sensor 106. The OPFE 102 folds an optical path to form a second optical path OP2 108 directed toward image sensor 106. Wide camera 130 includes a lens 132 having a plurality of lens elements (not visible in this representation) and an image sensor 138. Image sensor 138 may have a full sensor diagonal SD. Lens 132 is included in, and fixedly coupled to, a lens barrel 134. Wide camera 130 has an optical axis 136.

[0063] Some folded telephoto cameras, including folded zoom telephoto cameras, include a focus actuator configured to move components of the folded telephoto camera relative to each other to bring the camera into focus. In some examples, the lens barrel 110 is translatable substantially parallel to OP2 108 relative to the image sensor 106 (and relative to a mobile device including folded telephoto camera 100) to provide focusing or autofocusing. This type of focusing is referred to herein as lens focusing. For lens focusing, the folded telephoto camera 100 may include a lens actuator. In some examples, the lens actuator includes a guiding mechanism such as ball rails or ball bearings, and a motor such as a voice coil motor (VCM).

[0064] Recently, all lens on prism (ALOP) folded cameras were introduced. Examples of ALOP folded cameras are disclosed in co-owned international patent application PCT / IB2022 / 055745, which is incorporated herein by reference in its entirety. Fig. IB shows an example ALOP folded camera 170. ALOP folded camera 170 includes a lens assembly 172 having a plurality of N lens elements LI to L4 (in this example N = 4), an optical path folding element 174, and an image sensor 176. OPFE 174 may be implemented as a prism or as amirror. Light from an object enters ALOP folded camera 170 along a first optical path OP1 and is folded by OPFE 174 to a second optical path OP2. In the illustrated example, OP1 and OP2 are perpendicular to each other, however certain angles other than a right angle may be used. For example, an angle between OP1 and OP2 may be in a range between 75 degrees to 90 degrees providing an acute angle folded camera, or in a range between 90 degrees and 105 degrees providing an obtuse angle folded camera. For example, the angle between OP1 and OP2 may be 75 degrees or 80 degrees or 85 degrees. In some other examples, the angle between OP1 and OP2 may be 95 degrees or 100 degrees or 105 degrees.

[0065] Figs. 1C and ID illustrate a known lens actuator 180 configuration that may be used for lens focusing in folded camera modules. Fig. 1C shows lens actuator 180 in a side view. Lens actuator 180 includes a lens carrier 182 that carries a lens barrel, for example lens barrel 110, and that moves relative to a static surface 184. For actuation along the z axis, as indicated by arrow 189. The lens actuator 180 includes a motor (for example a VCM as described with respect to Fig. ID), a guiding mechanism 186 (e.g. ball rails or ball bearings), and a preload mechanism that provides a preload force 188 between lens carrier 182 and static surface 184.

[0066] The preload force 188 biases the lens carrier 182 toward the static surface 184 and helps maintaining engagement between the moving mass and the guiding structure. In known actuators, such preload is used to help achieve a relatively constant and reproducible position of the lens carrier 182 along the y-axis during focusing and during shock or vibration. A focusing movement (also referred to as a focusing stroke) may be, for example, in the range of 0.5 mm to 5 mm, or 0.5 mm to 2.5 mm. In the illustrated orientation, a height of the lens carried by lens carrier 182 may be measured along the y-axis.

[0067] Fig. ID shows the lens actuator 180 in a cross-sectional view. In this example, the lens actuator 180 includes a VCM having a first magnet 192-1 and a second magnet 192-2, and a first coil 194-1 and a second coil 194-2. Lens actuator 180 further includes a preload mechanism comprising a preload magnet 196 and a preload yoke 198. A preload force is generated by magnetic interaction between preload magnet 196 and preload yoke 198. Fig. ID also indicates a minimum (theoretical or optical) height of a folded telephoto camera including lens actuator 180, where the minimum height is defined by the stack of components included in lens actuator 180. As illustrated, the preload mechanism adds components along the height direction and therefore increases the minimum height of the folded camera module. This increased height can be undesirable in compact implementations, and motivates actuator configurations that provide the desired preload while reducing component count, weight, and height.In addition, in folded camera architectures, implementing optical image stabilization can present further mechanical constraints. In particular, providing stabilization while maintaining a compact module may be challenging, and motivates stabilization approaches that are compatible with folded optical paths and that can be implemented with limited impact on module height.

[0068] Reference is made to Figs. 2A and 2B, which exemplify a folded camera implementing optical image stabilization (OIS) according to some embodiments of the present disclosure.

[0069] Fig. 2A shows the folded camera in a representative (e.g., center or zero) OIS position, and Fig. 2B shows camera elements in a tilted position, for example in response to a detected change in camera orientation or location.

[0070] Fig. 2A exemplarily shows an all-lens-on-prism (ALOP) folded camera 200 in a cross section view. ALOP folded camera 200 is configured to perform OIS as described herein. Except for the addition of OIS capability, ALOP folded camera 200 may be similar in structure to known ALOP folded camera 170 described with reference to Fig. IB ALOP folded camera 200 includes a lens 172, an optical path folding element (OPFE) 174, and an image sensor 176 (collectively corresponding to lens 172, OPFE 174, and image sensor 176 of Fig. IB). Lens 172 may comprise a lens assembly including one or more lenses. In some examples, lens 172 comprises a plurality of lens elements, for example lens elements LI to L4. In the illustrated example, the lens assembly 172 and the OPFE 174 are included in a common block 202. Block 202 may include, for example, lens assembly 172 and OPFE 174 supported by one or more mechanical structures so that the lens assembly and the OPFE can be moved in combination for OIS. Block 202 may be implemented in actuality connecting the lens assembly 172 and OPFE 174 together forming a lens-and-OPFE assembly. Folded camera 200 is shown in a center (or zero) OIS position. In the illustrated orientation, when ALOP folded camera 200 is in the center OIS position, the second optical path OP2 is substantially parallel to a z axis, and a center of an object 208 to be captured may coincide with the first optical path OP1. In the illustrated example, OP1 and OP2 are perpendicular to each other.

[0071] Fig. 2B shows ALOP folded camera 200 in a cross-section view in a non center OIS position. For OIS about a first stabilization axis, the OIS operation includes coordinated angular motion of (i) block 202 and (ii) image sensor 176. In the illustrated example, block 202, which includes lens assembly 172 and OPFE 174, is rotated in combination by a first angle a about a rotation axis perpendicular to the y z coordinate system shown, the rotation axis passing through a pivot point 204. Simultaneously, image sensor 176 is rotated by a second angle(which in this example equals a) about a rotation axis perpendicular to the y z coordinate system shown, the rotation axis passing through a pivot point 206. Angle a may be in a range of 0 to 5 degrees, for example in a range of 0.25 to 2.5 degrees, and further for example in a range of 0.25 to 1.5 degrees. In the non center OIS position, a center of object 208 may no longer coincide with OP1, but rather may coincide with a direction 209 that is not parallel to OP1.

[0072] In general and as illustrated, pivot point 204 may be located at or near an intersection of OP1 and OP2, and pivot point 206 may be located at or near a center of image sensor 176. In other implementations, one or both of pivot point 204 and pivot point 206 may be located at other positions selected based on the optical and mechanical design.

[0073] The configuration of Figs. 2A and 2B is an example of a folded camera comprising a lens, an OPFE configured to fold a first optical path OP1 to a second optical path OP2, an image sensor, and an OIS actuator. In this example, the OIS actuator provides stabilization about a first stabilization axis by rotating the lens assembly and the OPFE in combination about a selected pivot (e.g., pivot point 204) by a first angle, and rotating the image sensor about another pivot (e.g., pivot point 206) by a second angle. The first and second angles may have a predetermined relation between them, which may include being equal, or being equal within a permitted angular variation selected so that the image formed on the image sensor remains within an acceptable focus tolerance, for example within a depth of focus of the lens assembly.

[0074] In some embodiments, the predetermined relation between the first angle (rotation of the lens and the OPFE in combination) and the second angle (rotation of the image sensor) is selected based on the optical design and packaging geometry of the folded camera. In some examples, the relation corresponds to equality within a permitted tolerance, for example where the second angle equals the first angle within a variation selected to maintain imaging performance. In other examples, the relation is a non-unity mapping, for example where the second angle equals k times the first angle, with k being greater than or less than unity, or where the second angle is defined by a function 02= f (0i) determined for the specific optical design (for example based on ray tracing, calibration, and / or a stored look-up table). The mapping may be selected such that, during OIS operation, the image formed on the image sensor remains within an acceptable focus tolerance, for example within a depth of focus of the lens or lens assembly, while compensating for camera motion over a range of stabilization angles.

[0075] For OIS about a second stabilization axis, methods known in the art may be used. Such methods are for example disclosed in co-owned international patent applicationPCT / IB2023 / 060577, describing folded-camera OIS in which motion data is obtained (data indicative of rotational movement of the module), and optical elements are spatially adjusted to compensate an optical path shift caused by the motion. Building on that approach, in some embodiments of the present disclosure the folded camera performs OIS about a second stabilization axis (in addition to OIS about the first stabilization axis described above) by applying an additional controlled motion of optical elements and / or the image sensor in response to detected camera motion.

[0076] In some embodiments, OIS about the second stabilization axis is implemented by linear translation of at least a portion of the optical system. For example, utilizing OIS in one direction by linearly moving a lens group along an axis parallel to the second optical axis (i.e., along the folded path direction). In the present disclosure, a similar concept may be applied such that, in response to detected motion, the OIS actuator linearly shifts a lens or lens assembly by a selected amount along a selected axis (for example, along an axis perpendicular to both OP1 and OP2, and / or along another axis selected by the optical / mechanical layout) to compensate for image motion in the second direction.

[0077] In some embodiments, OIS about the second stabilization axis is implemented by rotation about an axis parallel to the folded optical path. This configuration providing OIS in another direction by rotating together a lens group and an OPFE about an axis parallel to the second optical axis. Consistent with claims in the present application, the folded camera may implement second-axis OIS by rotating a lens and the OPFE in combination about a second rotation axis parallel to OP2 by a selected angle y, thereby compensating for motion components corresponding to the second direction.

[0078] In some embodiments, second-axis OIS includes coordinated motion of multiple components, optionally including the image sensor. For example, the folded camera may rotate the lens and the OPFE in combination about the second rotation axis while also rotating the image sensor (either about the same axis or about another axis selected by the mechanical design), with the relative magnitudes and timing of the movements selected to reduce residual image motion and / or to keep the image within an acceptable focus tolerance. More generally, the second-axis OIS may be implemented using one or more of: (i) lens / lens-assembly translation, (ii) rotation of the lens and OPFE in combination, and (iii) coordinated rotation of the lens, OPFE, and image sensor, with control parameters selected based on the optical design and calibrated for the specific module.

[0079] Accordingly, in some embodiments, optical image stabilization in a second direction, perpendicular to the plane defined by OP1 and OP2, is provided in addition to stabilizationabout the first stabilization axis. In this second direction, OIS may be achieved by translating the lens or lens assembly by a selected amount along an axis perpendicular to both OP1 and OP2, thereby shifting an image formed on the image sensor to compensate for camera motion. Additionally or alternatively, OIS in the second direction may be achieved by rotating the lens and the OPFE in combination about a second rotation axis that is parallel to OP2 by a selected angle y. In some embodiments, both approaches are combined, for example by applying a linear translation component together with a rotational component, with the respective magnitudes selected based on the optical design and calibration of the folded camera.

[0080] Reference is made to Figs. 3A and 3B, which exemplify another folded camera configuration implementing optical image stabilization (OIS) according to some embodiments of the present disclosure utilizing a selected fold angle P other than a right angle. Fig.3A shows the folded camera in a representative (e.g., center or zero) OIS position, and Fig. 3B shows camera elements in a tilted position, for example in response to a detected change in camera orientation or location. The configuration of Figs.3A and 3B illustrates that the disclosed OIS approach can be applied not only to folded layouts in which the folded optical paths are perpendicular, but also to layouts in which the folded optical paths form a non-right angle.

[0081] Fig.3A exemplarily shows an ALOP folded camera 300 in a cross-sectional view. ALOP folded camera 300 is configured to perform OIS as described herein. ALOP folded camera 300 includes a lens!72 and an optical path folding element (OPFE) 174, and an image sensor 176. Lens 172 may comprise a lens assembly including one or more lenses. In some examples, lens 172 comprises a plurality of lens elements, for example lens elements LI to L4. Light from an object 208 enters ALOP folded camera 300 along a first optical path OP1, and OPFE 174 folds OP 1 to a second optical path OP2. ALOP folded camera 300 is shown in a center (or zero) OIS position.

[0082] In contrast to the configuration of ALOP folded camera 200 shown in Fig. 2A, when ALOP folded camera 300 is in the center OIS position, OP2 forms a finite angle P with the z axis. In some examples, P is in a range of 1 to 10 degrees, for example 2 degrees or 3 degrees. In the illustrated configuration, OP1 and OP2 form an angle of less than 90 degrees with respect to each other. In the center OIS position, the center of object 208 to be captured may coincide with OP1, as shown.

[0083] Fig. 3B shows ALOP folded camera 300 in a cross-sectional view in a non center OIS position. For OIS about a first stabilization axis, the OIS operation includes coordinated angular motion of (i) a block 202 including the lens assembly and the OPFE, and (ii) image sensor 176.

[0084] In the illustrated example, block 202, which includes lens 172 and OPFE 174, is rotated incombination by a first angle a about a rotation axis perpendicular to the y z coordinate system shown, the rotation axis passing through a pivot point 204. Simultaneously, image sensor 176 is rotated by a second angle (which in this example equals a) about a rotation axis perpendicular to the y z coordinate system shown, the rotation axis passing through a pivot point 206. In the non center OIS position, the center of object 208 may no longer coincide with OP1, but rather may coincide with a direction 209 that is not parallel to OP1.

[0085] In general and as illustrated, pivot point 204 may be located at or near an intersection of OP1 and OP2, and pivot point 206 may be located at or near a center of image sensor 176. In other implementations, one or both of pivot point 206 and pivot point 204 may be located at other positions selected based on the optical and mechanical design.

[0086] The configuration of Figs. 3A and 3B is an example of a folded camera comprising a lens, an OPFE configured to fold a first optical path OP1 to a second optical path OP2, an image sensor, and an OIS actuator. In this example, the OIS actuator provides stabilization about a first stabilization axis by rotating the lens and the OPFE in combination about a selected pivot (e.g., pivot point 204) by a first angle, and rotating the image sensor about another pivot (e.g., pivot point 206) by a second angle. The first and second angles may have a predetermined relation between them, as described herein, including a relation selected so that an image formed on the image sensor remains within an acceptable focus tolerance, for example within a depth of focus of the lens assembly. It should also be noted that change in location of object 208 between Fig. 3A and 3B (as well as between Fig. 2A and 2B) is an illustration and is generally associated with relative angular direction to the object caused by a shift in orientation of the folded camera 300 (200) to which the OIS response.

[0087] Reference is further made to Figs.4A and 4B, exemplifying an additional folded camera configuration implementing optical image stabilization (OIS) according to some embodiments of the present disclosure, in which a lens or lens assembly is located at an image side of an optical path folding element (OPFE). Fig.4A shows the folded camera in a representative (e.g., center or zero) OIS position, and Fig. 4B shows camera elements in a tilted position, for example in response to a detected change in camera orientation or location.

[0088] Fig. 4A exemplarily shows a folded camera 400 in a cross section view. Folded camera 400 is configured to perform OIS as described herein. Folded camera 400 includes an OPFE 174 and an image sensor 176. Folded camera 400 further includes a lens 172 located at an image side of OPFE 174, such that the lens 172 receives light along OP2 after folding by OPFE 174. Lens 172 may be formed of a lens assembly including one or more lenses. In some examples, lens 172 including a plurality of lens elements, for example lens elements LI to L4(not shown in this view). Folded camera 400 is shown in a center (or zero) OIS position. In the illustrated orientation, when folded camera 400 is in the center OIS position, OP2 is substantially parallel to a z axis, and a center of an object 208 to be captured may coincide with OP1, as shown. In the illustrated example, OP1 and OP2 are perpendicular to each other.

[0089] Fig. 4B shows folded camera 400 in a cross-sectional view in a non center OIS position. For OIS about a first stabilization axis, the OIS operation includes coordinated angular motion of (i) a block 202 including the lens assembly and the OPFE, and (ii) image sensor 176. In the illustrated example, block 202, which includes lens 172 and OPFE 174, is rotated in combination by a first angle a about a rotation axis perpendicular to the y z coordinate system shown, the rotation axis passing through a pivot point 204. Simultaneously, image sensor 176 is rotated by a second angle (which in this example equals a) about a rotation axis perpendicular to the y z coordinate system shown, the rotation axis passing through a pivot point 206. In the non center OIS position, the center of object 208 may no longer coincide with OP1, but rather may coincide with a direction 209 that is not parallel to OP1.

[0090] In general and as illustrated, pivot point 204 may be located at or near an intersection of OP1 and OP2, and pivot point 206 may be located at or near a center of image sensor 176. In other implementations, one or both of pivot point 204 and pivot point 206 may be located at other positions selected based on the optical and mechanical design.

[0091] The configuration of Figs. 4A and 4B is an example of a folded camera comprising where the lens assembly 172 is located downstream of the OPFE 174 and utilizing an OIS actuator. In this example, the OIS actuator provides stabilization about a first stabilization axis by rotating the lens and the OPFE in combination about a selected pivot (e.g., pivot point 204) by a first angle, and rotating the image sensor about another pivot (e.g., pivot point 206) by a second angle. The first and second angles may have a predetermined relation between them, as described herein, including a relation selected so that an image formed on the image sensor remains within an acceptable focus tolerance, for example within a depth of focus of the lens assembly.

[0092] As indicated above, the OIS actuator may provide OIS along a second axis perpendicular to the plane defined by OP1 OP2. Such second axis OIS may utilize any selected OIS technique including angular and / or linear OIS shifts.

[0093] In some embodiments, the folded camera described herein includes, or is associated with, a controller configured to operate an OIS actuator based on detected motion during image acquisition. The controller may receive motion information from one or more motion sensors, such as one or more accelerometers and / or gyroscopes, and may determine a change in cameraorientation or location during an exposure or during a sequence of exposures. Based on the determined motion, the controller may generate OIS control data and drive the OIS actuator to perform the coordinated movements described herein, including rotation of a lens and an optical path folding element (OPFE) in combination about a selected pivot and rotation of an image sensor about another pivot according to a predetermined relation between respective rotation angles.

[0094] The controller may be implemented in different ways. In some embodiments, the controller is implemented using one or more processors of a corresponding electronic device, for example an application processor. In other embodiments, the controller is implemented as a dedicated camera controller, for example a microcontroller associated with the camera module. Generally, the controller may include one or more processors and a memory, and may be configured to execute pre stored computer readable instructions for generating the OIS control data and driving the OIS actuator. The memory may further store calibration data used to determine or select the predetermined relation between the first and second rotation angles, for example calibration data selected so that, during OIS operation, an image formed on the image sensor remains within an acceptable focus tolerance, for example within a depth of focus of a lens or lens assembly.

[0095] Reference is now made to Fig. 5, schematically illustrating an example of an electronic device 500 implementing OIS according to some embodiments of the present disclosure.

[0096] Fig. 5 shows schematically an embodiment of a mobile device 500, for example a smartphone, configured to perform OIS as described herein. Mobile device 500 includes a folded camera 510 (for example an ALOP camera, e.g., camera 200, 300 or 400 illustrated above) having a folded camera field of view (FOV) and including an image sensor 176. Folded camera 510 further includes a lens 174 and an OIS actuator 516 configured to actuate OIS movements as described herein.

[0097] Mobile device 500 further includes an application processor (AP) 530. In the illustrated example, AP 530 includes an OIS controller 532, an image sensor controller 534, and an image signal processor (ISP) 536. Mobile device 500 further includes a memory 540 and a screen 570. Memory 540 may be used, for example, to store calibration data of folded camera 510, and / or to store calibration data used for controlling OIS actuator 516, including calibration data for selecting the predetermined relation between rotation of optical elements and rotation of image sensor 512.

[0098] Mobile device 500 may further include an inertial measurement unit (IMU) 550 configured to measure motion of mobile device 500, including displacement and / or rotation,which may be corrected by OIS. IMU 550 may include, for example, one or more accelerometers and / or gyroscopes. In some examples, mobile device 500 includes a microcontroller unit (MCU) 560 configured to calculate OIS control data. In operation, motion data from IMU 550 may be processed by OIS controller 532 and / or MCU 560 to determine a change in camera orientation or location during image acquisition, and to generate control signals for driving OIS actuator 516.

[0099] OIS actuator 516 may include one or more motors and guiding elements. In some examples, OIS actuator 516 includes a voice coil motor (VCM) and one or more guiding elements such as two or more ball bearings configured to translate an actuation force provided by the VCM into one or more controlled OIS movements. The controlled OIS movements may include coordinated rotation of the lens 514 and an associated OPFE (not shown in Fig. 5, for example OPFE 174) in combination about a selected pivot, together with rotation of image sensor 512 about another pivot, according to the predetermined relation between respective rotation angles, as described herein.

[0100] Optionally, mobile device 500 may further include a second camera 520 including a second image sensor 522 and a second lens 524, e.g., as illustrated in Fig. 1A above. Calibration data stored in memory 540 may further include, for example, calibration data between folded camera 510 and second camera 520.

[0101] Accordingly, the present disclosure provides a folded camera and a corresponding optical image stabilization (OIS) mechanism in which, along at least one stabilization axis, OIS is performed by coordinated angular motion of (i) an image sensor and (ii) an optical path folding element (OPFE), optionally together with a lens or lens assembly. The relative angular relationship between the sensor rotation and the OPFE side rotation is selected based on the optical design of the folded camera and is not limited to a strictly identical rotation. In some embodiments, the relationship may be approximately unity, for example equal within a permitted variation, while in other embodiments the relationship may deviate from unity and may be defined by a selected function or mapping between the respective rotation angles, for example a mapping selected such that an image formed on the image sensor remains within an acceptable focus tolerance, such as within a depth of focus of the lens or lens assembly.

[0102] In another aspect, the present disclosure provides a lens actuator for a folded camera module in which a ferromagnetic preload yoke is arranged to magnetically interact with one or more magnets that are already part of a voice coil motor (VCM) focusing mechanism. In this way, the same actuation magnet(s) can be used both to generate a focusing force (via interaction with a coil) and to generate a preload force (via interaction with the yoke) that biases a movinglens carrier toward a guiding surface or guiding mechanism, while still allowing translation of the lens carrier for optical focusing. This approach can reduce component count, weight, and height, for example by avoiding a dedicated preload magnet and by avoiding placement of a yoke below the lens carrier along the height direction.

[0103] Reference is now made to Figs. 6A to 6D, exemplifying lens actuator configurations implementing the preload concept described above.

[0104] Fig. 6A exemplarily shows a lens actuator 600 (180) in a cross-sectional view. Lens actuator 600 is similar to known lens actuator 180, except of the preload mechanism thereof. Lens actuator 600 includes a first preload yoke 602-1 and a second preload yoke 602-2 fixedly coupled to static elements of the lens actuator, and positioned to apply, in combination with one or more magnets 192-1 and 192-2 a preload force biasing the lens carrier with respect to the static elements. In the illustrated example, preload yoke 602-1 is fixedly coupled to a first coil 194-1, and preload yoke 602-2 is fixedly coupled to a second coil 194-2. Coils 194-1 and 194-2 are fixed relative to a housing (not shown) and are static with respect to a mobile device including the folded camera. The first magnet 192-1 and the second magnet 192-2 are coupled to a lens carrier 182 and move with the lens carrier relative to coils 194-1 and 194-2 during focusing, while applying magnetic preload force onto the preload yokes 602-1 and 602-2.

[0105] In lens actuator 600, the preload force is composed of two preload force components. A first preload force component is generated by magnetic interaction between magnet 192-1 and preload yoke 602-1, and is schematically indicated by arrow 604-1. A second preload force component is generated by magnetic interaction between magnet 192-2 and preload yoke 602-2, and is schematically indicated by arrow 604-2.

[0106] Generally, the static elements may be integrated into selected printed boards that may be rigid or flexible. In some examples, coil 194-1 and preload yoke 602-1 are integrated into a first printed circuit board (PCB), and coil 194-2 and preload yoke 602-2 are integrated into a second PCB. The PCB may be a flex PCB (FPCB). Generally, the PCB may carry the at least one coil and the at least one preload yoke, or two coils and two yokes in accordance with the respective embodiment. The use of a symmetric configuration may provide for stable preload force, capable of withstanding hits or vibrations.

[0107] In such implementations, the preload yokes are disposed laterally with respect to the lens carrier 182, such that no preload yoke is positioned below the lens carrier along the height direction h (for example along the y axis discussed above with respect to Figs. 1C and ID).

[0108] The preload yokes may be offset relative to a center of the magnet height to provide a preload component toward a static actuator part, for example toward a guiding mechanism such as ballrails, thereby keeping the moving mass in contact with the guiding mechanism. In the illustrated symmetric configuration, lateral components along the x direction tend to be reduced or balanced by using yokes on opposite lateral sides. Compared to lens actuator 180, lens actuator 600 can reduce camera height h, as schematically indicated, to allow implementation within thin form factor electronic devices.

[0109] Fig. 6B exemplarily shows another lens actuator 620 in a cross-sectional view. Lens actuator 620 is similar to lens actuator 600, but uses a single sided preload arrangement. In lens actuator 620, a preload force is generated primarily as a single preload force component by magnetic interaction between magnet 192-1 and a preload yoke 602, as schematically indicated by arrow 604. As in other examples described herein, preload yoke 602 is fixed relative to the housing and is disposed laterally with respect to the lens carrier, thereby avoiding placement of a yoke below the lens carrier along the height direction. This configuration further reduces weight and elements with respect to the symmetric configuration of Fig. 6A.

[0110] Fig.6C exemplifies another lens actuator 650 configuration in a cross section view. Lens actuator 650 is similar to known lens actuator 180, other than its preload mechanism as disclosed herein. Lens actuator 650 includes a first preload yoke 602-1 fixedly coupled to a first coil 194-1, and a second preload yoke 602-2 fixedly coupled to a second coil 194-2. A first preload force component is generated by magnetic interaction between magnet 192-1 and preload yoke 602-1, as schematically indicated by arrow 604-1, and a second preload force component is generated by magnetic interaction between magnet 192-2 and preload yoke 602-2, as schematically indicated by arrow 604-2. The illustrated arrangement provides preload while allowing translation of lens carrier 182 for focusing. This configuration may utilize an increased width of the lens actuator structure, while maintaining height of the lens actuator.

[0111] Additionally, Fig. 6D exemplifies another lens actuator 670 configuration in a cross-sectional view. Lens actuator 670 is similar to lens actuator 650, but uses a single sided preload arrangement. In lens actuator 670, a preload force is generated primarily as a single preload force component by magnetic interaction between magnet 192-1 and a preload yoke 672, as schematically indicated by arrow 604. As schematically illustrated in Figs. 6C and 6D, positioning preload yokes 602-1, 602-2, or 602 laterally relative to lens carrier 182 can avoid increasing a height of a folded telephoto camera module along the height direction, which can be beneficial for integration into a slim mobile device.

[0112] The preload mechanisms illustrated in Figs. 6A to 6D may provide one or more of the following advantages. First, placing the preload yoke laterally relative to the lens carrier and avoiding placement below the lens carrier can reduce a folded camera module height that isconstrained by device thickness, and / or can enable a larger clear aperture for a given module height. Second, generating preload using a ferromagnetic yoke interacting with an actuation magnet can eliminate a dedicated preload magnet (for example preload magnet 196 in Fig. ID), reducing component count and cost. Third, where the actuator already includes an FPCB for electrical routing, integrating the yoke with the PCB environment can provide a low cost manufacturing approach. Fourth, combining the yoke placement with the VCM coil support structure can simplify assembly while still providing a preload force that biases the moving lens carrier toward the guiding mechanism.

[0113] Further reference is made to Figs. 7A to 7D, showing an example lens actuator assembly according to some embodiments of the present disclosure. Figs. 7A and 7B show exploded perspective views of the moving and static parts, and Figs.7C and 7D show perspective views in which the moving and static parts are assembled together.

[0114] Fig. 7A shows a lens actuator 700 in an exploded perspective view, and Fig. 7B shows lens actuator 700 in another exploded perspective view. Lens actuator 700 includes a lens carrier 710 and a camera housing 720 (housing of lens actuator). Lens carrier 710 may be fixedly coupled to a lens or lens assembly (not shown) and is movable with respect to camera housing 720, which may be fixed relative to an image sensor, not shown, of a camera including lens actuator 700. A position of a lens in lens carrier 710 is schematically indicated at 712.

[0115] Lens carrier 710 includes a first magnet 192-1 positioned at a first lateral side and a second magnet 192-2 positioned at a second lateral side opposite the first lateral side. Lens carrier 710 may further include a sensing magnet 716, a stray light mask 718 configured to reduce an amount of stray light entering the lens, and one or more rails (not shown) for guiding translation of the lens carrier relative to camera housing 720.

[0116] Camera housing 720 includes a first preload yoke 602-1 fixedly coupled to a first flex PCB 724-1, and a second preload yoke 602-2 fixedly coupled to a second flex PCB 724-2 on a second lateral side opposite the first lateral side. In other examples, camera housing 720 includes only one preload yoke, which may be located at the first lateral side or at the second lateral side. Camera housing 720 further includes a first coil 194-1 positioned at the first lateral side and a second coil 194-2 positioned at the second lateral side opposite the first lateral side. Coils 194-1 and 194-2 are arranged to interact with magnets 192-1 and 192-2 to generate an actuation force for translating lens carrier 710 along a lens optical axis for focusing.

[0117] Camera housing 720 further includes a first rail 728-1 and a second rail 728-2. Rails 728-1 and 728-2 engage with corresponding rails of lens carrier 710 (not shown). Two or more balls (not shown) may be confined within the engaged rails, acting as ball bearings and allowingrelative translation of lens carrier 710 with respect to camera housing 720 while providing guidance and repeatability of motion. The preload yokes 602-1 and 602-2 cooperate magnetically with magnets 192-1 and 192-2 to generate one or more preload force components that bias lens carrier 710 toward a guiding surface or guiding mechanism, for example toward rails 728-1 and 728-2, while maintaining compact height by positioning the preload yokes laterally rather than below the lens carrier along a height axis.

[0118] Fig. 7C shows lens actuator 700 in a perspective view with moving and static parts assembled, and Fig. 7D shows lens actuator 700 in another perspective view. In Fig. 7C, an OPFE holder 730 is visible. OPFE holder 730 may fixedly hold an OPFE (for example a prism), where the OPFE is configured to fold a first optical path from a scene toward a second optical path directed toward an image sensor of a folded camera module including lens actuator 700.

[0119] Lens actuator 700 may be configured to provide a relatively low camera height. A height H of lens actuator 700 measured along a height axis (for example corresponding to the y axis described above) may be in a range of 4 mm to 13 mm, for example 4 mm to 11 mm, and further for example 4 mm to 9 mm. A length L of lens actuator 700 may be, for example, in a range of 5 mm to 50 mm, for example 5 mm to 30 mm, and further for example 10 mm to 25 mm. A folded camera module including lens actuator 700 may have a camera height in a range of, for example, 5 mm to 15 mm, 5 mm to 12.5 mm, or 5 mm to 10 mm, depending on the optical design and packaging constraints.

[0120] Accordingly, in some aspects, the present disclosure provides a folded camera module including a lens actuator in which a lens carrier is configured to carry at least one lens and to be translatable along a lens optical axis over a focusing stroke for focusing. The lens actuator includes a housing, at least one coil fixed relative to the housing, and at least one magnet coupled to the lens carrier and arranged to interact with the coil to generate an actuation force for translating the lens carrier along the lens optical axis. The lens actuator further includes at least one ferromagnetic preload yoke fixed relative to the housing and arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface or guiding mechanism, for example toward rails, ball rails, or other guide elements that constrain translation.

[0121] Further, Fig. 8 schematically illustrates an example electronic device 800, typically a handheld device such as a smartphone, including one or more camera modules. In the illustrated example, electronic device 800 includes at least one folded camera module 810.

[0122] Folded camera module 810 includes an optical path folding element (OPFE) 174, a lens assembly 172, and an image sensor 176. The OPFE 174 is configured to fold a first optical pathto a second optical path toward the image sensor, enabling a folded optical layout suitable for compact device form factors.

[0123] In some embodiments, folded camera module 810 is configured to perform optical image stabilization (OIS) as described herein. For example, folded camera module 810 may include an OIS actuator configured to provide stabilization about a first stabilization axis by rotating the lens assembly 172 and OPFE 174 in combination about a selected pivot by a first angle, and rotating the image sensor about another pivot by a second angle, wherein the first and second angles have a predetermined relation between them. The predetermined relation may be selected based on the optical design of folded camera module 810, and may be selected such that an image formed on the image sensor remains within an acceptable focus tolerance, for example within a depth of focus of the lens assembly. In some examples, the predetermined relation corresponds to the first and second angles being equal within a permitted angular variation relative to the first angle.

[0124] In some embodiments, folded camera module 810 further includes a lens actuator configured to translate at least one lens of lens assembly 172 along a lens optical axis for focusing. The lens actuator may include a lens carrier configured to carry the at least one lens and to be translatable along the lens optical axis, a housing, a coil coupled to the housing, and a magnet coupled to the lens carrier and arranged to interact with the coil to generate an actuation force for translating the lens carrier along the lens optical axis. The translation may be guided by one or more guiding surfaces or guiding mechanisms, such as rails, ball rails, or other guide elements.

[0125] In further embodiments, folded camera module 810 includes a preload mechanism configured to bias the lens carrier toward a guiding surface or guiding mechanism. In some examples, the preload mechanism includes a ferromagnetic preload yoke fixed relative to the housing and arranged to magnetically interact with the magnet coupled to the lens carrier to generate a preload force. In preferred implementations, the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis perpendicular to the lens optical axis. In this manner, the preload force may be generated using one or more magnets associated with a voice coil motor (VCM) of the lens actuator, thereby omitting the need for a dedicated preload magnet distinct from the magnet coupled to the lens carrier. This can reduce component count, cost, and height, while maintaining desired bias of the lens carrier toward the guiding mechanism.

[0126] Electronic device 800 may include one or more processors and a memory configured to control operation of folded camera module 810, including control of OIS and control offocusing. In some embodiments, the electronic device includes motion sensors, such as an inertial measurement unit, configured to detect motion of electronic device 800 during image acquisition, and the one or more processors are configured to generate control signals for driving the OIS actuator in response to the detected motion.

[0127] In preferred implementations, the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis perpendicular to the lens optical axis. This lateral placement can reduce the minimum height of the actuator and / or can enable a larger clear aperture for a given actuator height. In some embodiments, the preload force is generated without a dedicated preload magnet distinct from the magnet coupled to the lens carrier, thereby reducing component count and simplifying assembly. In some embodiments, the lens actuator includes multiple voice coil motors and multiple preload yokes, for example with yokes disposed on opposite lateral sides to balance lateral force components while providing the desired bias toward the guiding mechanism. Overall, the disclosed actuator concepts can reduce size, weight, and cost while maintaining stable engagement of the moving lens carrier with the guiding mechanism during focusing and during external disturbances.

[0128] It is appreciated that certain features of the presently disclosed subject matter, which are, for clarity, described in the context of separate examples, may also be provided in combination in a single example. Conversely, various features of the presently disclosed subject matter, which are, for brevity, described in the context of a single example, may also be provided separately or in any suitable sub-combination.

[0129] Unless otherwise stated, the use of the expression “and / or” between the last two members of a list of options indicates that a selection of one or more of the listed options is appropriate and may be made.

[0130] It should be understood that where the claims or specification refer to “a” or “an” element, such reference is not to be construed as there being only one of that element.

[0131] All patents and patent applications mentioned in this specification are incorporated herein by reference in their entirety, to the same extent as if each individual patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present disclosure.

[0132] While this disclosure has been described in terms of certain examples and generally associated methods, alterations and variations will be apparent to those skilled in the art. The present disclosure is not limited by the specific examples described herein, but only by thescope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A folded camera, comprising:a lens;an optical path folding element (OPFE), configured to fold a first optical path OP1 to a second optical path OP2;an image sensor; andan optical image stabilization (OIS) actuator,wherein, the optical image stabilization actuator provides for optical image stabilization about a first stabilization axis, and is configured to rotate the lens and the OPFE in combination about a selected pivot by a first angle and rotate the image sensor about a second pivot by a second angle, and wherein the first and second angles have a predetermined relation between them.

2. The folded camera of claim 1, wherein the first and second angles are equal up to an angular variation of 10% of the first angle.

3. The folded camera of claim 1 or 2, wherein the lens is located at an object side of the OPFE.

4. The folded camera of claim 1 or 2, wherein the lens is located at an image side of the OPFE.

5. The folded camera of any one of claims 1 to 4, wherein a pivot point for rotating the lens and the OPFE in combination is located at an intersection of the first optical path and the second optical path.

6. The folded camera of any one of claims 1 to 5, wherein the image sensor has a center position, and wherein a pivot point for rotating the image sensor is located at the center position of the image sensor.

7. The folded camera of any one of claims 1 to 6, wherein the OPFE is a prism.

8. The folded camera of any one of claims 1 to 7, wherein the OIS actuator is further configured to provide OIS in a second direction perpendicular to a plane defined by OP1 and OP2.

9. The folded camera of claim 8, wherein the OIS actuator is further operational to linearly move the lens along an axis perpendicular to both OP 1 and OP2 by a selected amount to provide OIS in the second direction.

10. The folded camera of claim 8, wherein the OIS actuator is further operational to rotate the lens and the OPFE by a selected angle y about a second rotation axis parallel to OP2 to provide OIS in the second direction.

11. The folded camera of claim 8, wherein the OIS actuator further comprises a second actuator operable for rotation about the second rotation axis, the second rotation axis being parallel to OP2, and wherein the OIS actuator is operational to rotate the lens, the OPFE and the image sensor together by another angle y about the second rotation axis.

12. The folded camera of any one of claims 1 to 11, wherein OP1 and OP2 are perpendicular to each other.

13. The folded camera of any one of claims 1 to 11, wherein an angle between OP1 and OP2 is smaller than 90 degrees.

14. The folded camera of any one of claims 1 to 13, wherein the first angle is in a range of 0 to 5 degrees.

15. The folded camera of any one of claims 1 to 13, wherein the first angle is in a range of 0.25 to 2.5 degrees.

16. The folded camera of any one of claims 1 to 13, wherein the first angle is in a range of 0.25 to 1.5 degrees.

17. The folded camera of any one of claims 1 to 16, wherein the image sensor has a full diagonal SD, and wherein SD is in a range of 5 mm to 20 mm.

18. The folded camera of claim 17, wherein SD is at most 12.5 mm.

19. The folded camera of any one of claims 1 to 18, wherein an f-number (f / #) of the camera is in a range of 1.5 < f / # < 3.

20. The folded camera of claim 19, wherein f / # is in a range of 2 < f / # < 2.75.

21. The folded camera of any one of claims 1 to 20, wherein the predetermined relation is selected such that an image formed on the image sensor remains within a depth of focus of the lens.

22. A mobile device comprising the folded camera of any one of claims 1 to 21.

23. The mobile device of claim 22, wherein the mobile device is a smartphone.

24. A lens actuator for a folded camera module, comprising:a lens carrier configured to carry at least one lens and to be translatable along a lens optical axis;a housing;a magnet coupled to the lens carrier;a coil coupled to the housing and arranged to interact with the magnet to generate an actuation force for translating the lens carrier along the lens optical axis; anda ferromagnetic preload yoke fixed relative to the housing,wherein the preload yoke is arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the actuator,wherein the folded camera module is operational to capture light received from a scene along a first direction,and wherein the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis parallel to the first direction.

25. The lens actuator of claim 24, wherein the coil and the magnet form a voice coil motor (VCM) configured to translate the lens carrier along the lens optical axis, and wherein the magnet is a VCM magnet of the voice coil motor.

26. The lens actuator of claim 24 or 25, wherein the lens actuator is free of a dedicated preload magnet distinct from the magnet coupled to the lens carrier.

27. The lens actuator of any one of claims 24 to 26, wherein translation of the lens carrier translates the lens along the lens optical axis.

28. The lens actuator of any one of claims 24 to 27, wherein the preload yoke is disposed on a first lateral side of the lens carrier, and wherein no preload yoke is disposed on a second lateral side of the lens carrier opposite the first lateral side.

29. The lens actuator of any one of claims 24 to 28, wherein the lens actuator comprises a first voice coil motor (VCM) and a second voice coil motor (VCM), each VCM comprising a respective coil and a respective magnet, and wherein the lens actuator comprises a first preload yoke and a second preload yoke.

30. The lens actuator of claim 29, wherein the first preload yoke is disposed on a first lateral side of the lens carrier and the second preload yoke is disposed on a second lateral side of the lens carrier opposite the first lateral side.

31. The lens actuator of claim 29 or 30, wherein the first preload yoke is arranged to magnetically interact with a magnet of the first VCM to generate a first preload force, and wherein the second preload yoke is arranged to magnetically interact with a magnet of the second VCM to generate a second preload force.

32. The lens actuator of any one of claims 24 to 31 , wherein the height axis is perpendicular to the lens optical axis.

33. The lens actuator of any one of claims 24 to 32, wherein the lens carrier is translatable along the lens optical axis along a focusing stroke of 0.5mm - 5mm.

34. The lens actuator of any one of claims 24 to 33, wherein a height of the lens actuator measured along a height axis perpendicular to the lens optical axis is in the range of 4 mm to 13 mm.

35. The lens actuator of claim 34, wherein the height of the lens actuator is in the range of 4mm to 11mm.

36. The lens actuator of claim 34, wherein the height of the lens actuator is in the range of 4mm to 9mm.

37. The lens actuator of any one of claims 24 to 36, wherein at least one lens comprises a lens arrangement having an effective focal length EFL in a range of 10 mm < EFL < 40 mm.

38. The lens actuator of any one of claims 24 to 37, included in a folded camera module, wherein the folded camera module comprises an optical path folding element (OPFE) for folding a first optical path (OP1) to a second optical path (OP2), and wherein OP2 is parallel to the lens optical axis.

39. A lens actuator for use in a folded camera module, comprising:a lens arrangement comprising N lens elements and having a lens optical axis, the lens arrangement being mounted on a lens carrier;a printed circuit board (PCB);at least one voice coil motor (VCM) comprising at least one coil and at least one magnet;and at least one ferromagnetic preload yoke,wherein the lens actuator is operational to actuate the lens carrier along the lens optical axis for focusing utilizing actuation force from the at least one VCM, wherein the PCB carries the at least one coil and the at least one preload yoke, and wherein the at least one magnet and the at least one preload yoke are operational to provide a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator.

40. A folded camera, comprising:a lens;an optical path folding element (OPFE) configured to fold a first optical path OP1 to a second optical path OP2;an image sensor; andan optical image stabilization (OIS) actuator,wherein the OIS actuator is configured, for optical image stabilization about a first stabilization axis, to rotate the lens and the OPFE in combination about a selected pivot by a first angle, and to rotate the image sensor about a second pivot by a second angle, and wherein the first and second angles have a predetermined relation between them.

41. A folded camera, comprising:a lens;an optical path folding element (OPFE) configured to fold a first optical path OP1 to a second optical path OP2;an image sensor; andan optical image stabilization (OIS) actuator,wherein the OIS actuator is configured, for optical image stabilization about a first stabilization axis, to rotate the lens and the OPFE in combination about a selected pivot by a first angle, and to rotate the image sensor about a second pivot by a second angle, wherein the first and second angles have a predetermined relation between them, and wherein the predetermined relation is selected such that an image formed on the image sensor remains within a depth of focus of the lens.

42. A folded camera module, comprising:an optical path folding element (OPFE) configured to fold a first optical path (OP1) to a second optical path (OP2); anda lens actuator, comprising:a lens carrier configured to carry at least one lens and to be translatable along a lens optical axis;a housing;a magnet coupled to the lens carrier;a coil coupled to the housing and arranged to interact with the magnet to generate an actuation force for translating the lens carrier along the lens optical axis; anda ferromagnetic preload yoke fixed relative to the housing,wherein the preload yoke is arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator,and wherein the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis perpendicular to the lens optical axis,wherein OP2 is parallel to the lens optical axis.

43. The folded camera module of claim 42, wherein the lens actuator is free of a dedicated preload magnet distinct from the magnet coupled to the lens carrier.

44. An electronic device, comprising:a folded camera comprising a lens, an optical path folding element (OPFE) configured to fold a first optical path OP1 to a second optical path OP2, an image sensor, and an optical image stabilization (OIS) actuator,wherein the OIS actuator is configured, for optical image stabilization about a first stabilization axis, to rotate the lens and the OPFE in combination about a selected pivot by a first angle, and to rotate the image sensor about a second pivot by a second angle, and wherein the first and second angles have a predetermined relation between them.

45. An electronic device, comprising:a folded camera module comprising an optical path folding element (OPFE) configured to fold a first optical path (OP1) to a second optical path (OP2); anda lens actuator comprising:a lens carrier configured to carry at least one lens and to be translatable along a lens optical axis;a housing;a magnet coupled to the lens carrier;a coil coupled to the housing and arranged to interact with the magnet to generate an actuation force for translating the lens carrier along the lens optical axis; anda ferromagnetic preload yoke fixed relative to the housing,wherein the preload yoke is arranged to magnetically interact with the magnet to generate a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator,and wherein the preload yoke is disposed laterally with respect to the lens carrier such that no preload yoke is disposed below the lens carrier along a height axis perpendicular to the lens optical axis.

46. An electronic device, comprising:a folded camera module; anda lens actuator for use in the folded camera module, the lens actuator comprising:a lens arrangement comprising N lens elements and having a lens optical axis, a lens height measured along a height axis perpendicular to the lens optical axis, and the lens arrangement being mounted on a lens carrier;a printed circuit board (PCB);at least one voice coil motor (VCM) comprising at least one coil and at least one magnet; and at least one ferromagnetic preload yoke,wherein the lens actuator is operational to actuate the lens carrier along the lens optical axis for focusing utilizing actuation force from the at least one VCM,wherein the PCB carries the at least one coil and the at least one preload yoke, and wherein the at least one magnet and the at least one preload yoke are operational to provide a preload force that biases the lens carrier toward a guiding surface or guiding mechanism of the lens actuator.

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