Slim compact camera actuators utilizing short VCM elements

Abstract

A camera module, comprising: a lens unit, a camera actuator comprising: first and second moving frames, a static frame, at least one actuation module utilizing a coil and a magnet, and a movement decoupling arrangement. The camera actuator provides a first actuation of the first moving frame and the second moving frame together and relative to the static frame along a first actuation direction, and a second actuation of the first moving frame relative ot the second moving frame along a second actuation direction perpendicular to the first actuation direction. The decoupling arrangement allows a movement of the magnet and the second moving frame together and relative to the coil along the second actuation direction, prevents a movement of the magnet relative to the coil along the first actuation direction.

Description

[0001] SLIM COMPACT CAMERA ACTUATORS UTILIZING

[0002] SHORT VCM ELEMENTS

[0003] FIELD

[0004] The present disclosure relates in general to digital cameras, and in particular to actuators for digital cameras with optical image stabilization (OIS) and focusing.

[0005] BACKGROUND

[0006] Camera modules of modern mobile devices such as smartphones, tablet computers, headsets etc. are typically characterized by:

[0007] 1. A low thickness (or height), i.e. the camera module is “slim” to fit into a casing of the mobile devices.

[0008] 2. A small width and length, i.e. be “compact” to fit into a casing of the mobile devices together with additional elements of the mobile device.

[0009] 3. Relatively inexpensive components.

[0010] For improving a camera’ s image quality, modern camera modules usually include optical image stabilization (OIS) and focusing. OIS cancels (or counteracts) an undesired motion of an image at the image sensor plane during the image sensor’s exposure. Without cancellation of the OIS, the undesired motion would cause a blurring of the image. Such undesired motion is for example caused by an unintentional movement or shaking of a user’s hands holding a mobile device during capturing of an image, herein referred to as handshake. In most current smartphones, OIS is used to correct for handshake around two of the three rotation axes of the mobile device. Explicitly, OIS is used to correct for handshake around the two rotation axes which are perpendicular to a normal of an image sensor included in the camera, or in other words, perpendicular to the optical axis of a lens unit included in the camera. To achieve correction for handshakes, OIS operates to perform linear movements of the lens (relative to the image sensor or vice versa), or of the entire camera (relative to the mobile device) in two directions perpendicular to the optical axis of the lens unit. The movements are performed so that they counteract (or mitigate) the handshake, such that an image on the image sensor plane does not move with respect to the image sensor or is captured with minimal movement. That is, the movements are performed so that the image is stabilized. OIS may operate in several techniques including “lens-shift OIS” where the lens unit is moved relative to the image sensor (and relative to the smartphone including the camera), and “sensor-shift OIS” where the image sensor is moved relative to the lens (and relative to the smartphone including the camera).

[0011] Focusing operation brings a camera into focus, so that a crisp (or sharp) image is formed on an image sensor. This operation is also referred to as “autofocusing” or “AF” when performed automatically using one or more processors. The focusing operation may utilize “lens-shift focusing” where one or more lenses of the lens unit are linearly moved relative to the image sensor (and relative to the smartphone including the camera) along an axis parallel to the lens optical axis, or “sensor-shift focusing” where an image sensor is linearly moved relative to the lens unit (and relative to the smartphone including the camera) along an axis parallel to a normal of the image sensor. An actuation module (or “actuation assembly”) includes all the mechanical components that are required for performing these movements.

[0012] In some examples, e.g. such as shown in co-owned international patent applications PCT / IB2022 / 052194 and PCT / 2023 / 052461, which are incorporated herein by reference in its entirety, actuation in the first direction is transmitted by a “ball-bearing” mechanism as known in the art. For transmitting, one or more balls of the ball-bearings are enclosed in and move in a linear rail formed in an interspace (or void) between two grooves, each groove being included in different components (or parts) which move relatively to each other.

[0013] GENERAL DESCRIPTION

[0014] Typical OIS arrangements and the respective actuators utilize relative movement between a first and a second moving frame and a static frame along two axes. While a first actuator may shift the first moving frame with respect to the static frame, this movement may cause relative shift between elements of a second actuator operable for shifting the second moving frame along a second axis. To maintain operation of the second actuator, conventional camera modules utilize a magnet having excess length with respect to a coil, where the magnet and coil define the second actuator and operate to generate actuation force between them. Such excess length of the magnet (or coil) of the second actuator results in increased weight, cost and size of the camera module. Accordingly, there is need in the art for a compact, relatively inexpensive and low-crosstalk camera actuators. The present disclosure provides for decoupling movement of the magnet and / or coil of a second actuator from movement of the first moving frame, operable by a first actuator. Such decoupling eliminates, or at least significantly reduces the need for excess length of the magnet to maintain spatial overlap between the magnet and coil of the second actuator for different locations of the first moving frame. Eliminating the need for an excess magnet (or coil) length enables to reduce the cost, weight and / or size of the camera module, and may reduce magnetic crosstalk between elements of the camera module and other elements that may be used in a device incorporating such camera module. This configuration may be beneficial in various configurations including handheld camera, smartphones, tablets, smartwatches and various other electronic devices utilizing a camera module.

[0015] Thus according to a first broad aspect, the present disclosure provides a camera module, comprising: a lens unit, a camera actuator comprising: first and second moving frames, a static frame, at least one actuation module utilizing a coil and a magnet, and a movement decoupling arrangement; wherein the camera actuator provides a first actuation of the first moving frame and the second moving frame together and relative to the static frame along a first actuation direction, and a second actuation of the first moving frame relative of the second moving frame along a second actuation direction perpendicular to the first actuation direction; and wherein the decoupling arrangement allows a movement of the magnet and the second moving frame together and relative to the coil along the second actuation direction and prevents a movement of the magnet relative to the coil along the first actuation direction.

[0016] According to a second broad aspect, the present disclosure provides a camera module, comprising: a lens unit having a lens optical axis and an effective focal length EFL in the range of 2.5mm to 50mm; a camera actuator comprising: a first moving frame, a second moving frame, a static frame, a coil fixedly attached to the static frame, a magnet having a magnet length, and a first set of ball-bearings and a second set of ball-bearings, wherein the camera actuator provides a first actuation of the first moving frame and the second moving frame together and relative to the static frame along a first actuation direction, wherein the first set of ball-bearings is positioned between the first moving frame and the second moving frame and enabling a second actuation along a second actuation direction perpendicular to the first actuation direction, wherein the second set of ball-bearings allows a movement of the magnet and the second moving frame together and relative to the coil along the second actuation direction, and wherein the second set of ball-bearings prevents a movement of the magnet relative to the coil along the first actuation direction.

[0017] According to some embodiments, the magnet and the coil have a substantially similar length along the first actuation direction. In this connection, the term ‘substantially’ relates to length variation of up to 20%. Further, the length of the magnet may be selected in accordance with the length of the coil to provide efficient operation of the camera actuator, while avoiding excess material of the magnet or the coil.

[0018] According to some embodiments, the camera actuator is operable to actuate the lens for optical image stabilization (OIS), wherein the first actuation direction represents a first OIS direction, wherein the second actuation represents a second OIS direction, and wherein both the first OIS direction and the second OIS direction are perpendicular to the lens optical axis.

[0019] According to some embodiments, the OIS is in an OIS movement range of less than 2.5mm in both the first OIS direction and the second OIS direction.

[0020] According to some embodiments, the OIS is in an OIS movement range of less than 1.5mm in both the first OIS direction and the second OIS direction.

[0021] According to some embodiments, the camera comprises an image sensor having an image sensor normal, wherein the camera actuator is operational to actuate the image sensor for optical image stabilization (OIS), wherein the first actuation direction represents a first OIS direction, wherein the second actuation direction represents a second OIS direction, and wherein both the first OIS direction and the second OIS direction are perpendicular to the image sensor normal.

[0022] According to some embodiments, the OIS has an OIS movement range of less than 2.5mm in both the first OIS direction and the second OIS direction.

[0023] According to some embodiments, the OIS has an OIS movement range of less than 1.5mm in both the first OIS direction and the second OIS direction. According to some embodiments, the camera module may comprise a camera module housing, and wherein at least a part of the camera module housing is the static frame.

[0024] According to some embodiments, the first moving frame and the second moving frame have a moving frame height HMFI and HMF2 respectively, wherein the static frame has a static frame height HSF, wherein HMFI and HMF2 are in the range of 0.25mm to 2mm and wherein HSF is in the range of 0.25mm to 2.5mm.

[0025] According to some embodiments, the first moving frame and the second moving frame have a moving frame width WMFI and WMF2 respectively, wherein the static frame has a static frame width WSF, wherein WMFI and WMF2 are in the range of 10mm to 40mm and wherein WSF is in the range of 10mm to 40mm.

[0026] According to some embodiments, the camera actuator is included in an OIS module that has an OIS module height HM in the range of 0.5mm to 5mm.

[0027] According to some embodiments, the camera actuator is included in an OIS module that has an OIS module width WM in the range of 10mm to 40mm.

[0028] According to some embodiments, the camera actuator comprises a Hall sensor.

[0029] According to some embodiments, the EFL of the lens unit is in the range of 2.5mm to 30mm.

[0030] According to some embodiments, the EFL of the lens unit is in the range of 2.5mm to 15mm.

[0031] According to some embodiments, the camera is a pop-out camera.

[0032] According to some embodiments, the camera is included in a mobile device. The mobile device may be a smartphone, a tablet, a smart watch or other handheld devices.

[0033] According to a third broad aspect, the present disclosure provides a camera module comprising: a lens unit defining an optical axis; a sensor array; a camera actuator comprising a first moving frame, a second moving frame, a static frame, a first actuation motor actuating movement of the first moving frame in a first actuation direction and a second actuation motor actuating movement of the second moving frame in a second actuation direction; wherein the second actuation motor comprises a magnet and a coil operable for generating actuation force; and wherein the magnet and coil are decoupled from movement of the first moving frame along the first actuation direction, and configured to actuate movement of the second moving frame along the second actuation direction. According to some embodiments, the magnet and the coil have substantially similar length along the first actuation direction.

[0034] According to a fourth aspect, the present disclosure provides an electronic device comprising at least one camera module, the at least one camera module comprising: a lens unit defining an optical axis; a sensor array; a camera actuator comprising a first moving frame, a second moving frame, a static frame, a first actuation motor actuating movement of the first moving frame in a first actuation direction and a second actuation motor actuating movement of the second moving frame in a second actuation direction; wherein the second actuation motor comprises a magnet and a coil operable for generating actuation force; and wherein the magnet and coil are decoupled from movement of the first moving frame along the first actuation direction, and configured to actuate movement of the second moving frame along the second actuation direction.

[0035] According to a fifth aspect, the present disclosure provides an electronic device comprising a camera module, the camera module comprising: a lens unit having a lens optical axis and an effective focal length EFL in the range of 2.5mm to 50mm; a camera actuator comprising: a first moving frame, a second moving frame, a static frame, a coil fixedly attached to the static frame, a magnet having a magnet length, and a first set of ball-bearings and a second set of ball-bearings, wherein the camera actuator provides a first actuation of the first moving frame and the second moving frame together and relative to the static frame along a first actuation direction, wherein the first set of ball-bearings is positioned between the first moving frame and the second moving frame and enabling a second actuation along a second actuation direction perpendicular to the first actuation direction, wherein the second set of ball-bearings allows a movement of the magnet and the second moving frame together and relative to the coil along the second actuation direction, and wherein the second set of ball-bearings prevents a movement of the magnet relative to the coil along the first actuation direction.

[0036] In some embodiments, the electronic devices described herein may be handheld devices, being a smartphone, tablet, smartwatch or any other handheld devices. Generally, aspects of the present disclosure may include features described herein with respect to other aspects and embodiments of the present disclosure.

[0037] BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Fig. 1 A shows schematically an actuation module moving a lens as known in the art in a top view;

[0039] Fig. IB shows schematically a camera that includes an actuation module as known in the art in a side view;

[0040] Fig. 1C shows the camera of Fig. IB in a zero position in a top view;

[0041] Fig. ID shows the camera of Fig. IB in a maximum position in a top view;

[0042] Fig. IE shows the camera of Fig. IB in a minimum position in a top view;

[0043] Fig. 2A shows schematically a camera that includes an actuation module as disclosed herein in a zero position in a top view;

[0044] Fig. 2B shows the camera of Fig. 2A in a maximum position in a top view;

[0045] Fig. 2C shows the camera of Fig. 2A in a minimum position in a top view;

[0046] Fig. 3 A shows parts of an embodiment of a camera module including a camera actuator as disclosed herein in a perspective view.

[0047] Fig. 3B shows a zoom-in area of the camera module of Fig. 3 A in a perspective view.

[0048] Fig. 3C shows another zoom-in area of the camera module of Fig. 3 A in a perspective view;

[0049] Fig. 3D shows the camera module of Fig. 3 A in a cross-sectional view;

[0050] Fig. 3E shows the camera module of Fig. 3 A in another cross-sectional view;

[0051] Fig. 4A shows the camera module of Fig. 3 A in a zero position in a top view;

[0052] Fig. 4B shows the camera module of Fig. 3 A in a maximum position in a top view;

[0053] Fig. 4C shows the camera module of Fig. 3 A in a minimum position in a top view.

[0054] DETAILED DESCRIPTION

[0055] Figs. 1A to ID exemplify a schematic configuration and operation scheme of optical image stabilization (OIS) as known in the art. Fig. 1 A shows in a top view a schematic of an actuation module for moving a lens 102 for OIS as known in the art; Fig. IB illustrates a cross section view of the camera 120; Figs. 1C to IE illustrate a top view of the camera 120 exemplifying movement of a second moving frame 134 along a corresponding first actuation axis 148 based on operation of the OIS. An image sensor (126 in Fig. IB) is generally oriented parallel to the x-y plane. The optical axis (124 in Fig. IB) of lens 102 is oriented perpendicular to the shown x-y plane. For OIS, lens 102 is moved perpendicular to its optical axis from an initial position characterized by an initial center position 104 of lens 102 (“Xi”) to a final center position 106 (“XF”). For performing this movement of lens 102, lens 102 is linearly moved in the x-direction as indicated by arrow 112, and, in addition, lens 102 is linearly moved in the y- direction as indicated by arrow 114. The two movements may be performed simultaneously or sequentially.

[0056] Fig. IB schematically shows a cross-sectional view of a camera 120 that includes a lens unit 122 having a lens optical axis 124, an image sensor 126 (e.g., a sensor array) and an actuation module 130 as known in the art. In this example, actuation module 130 is a lens-shift OIS module operational to perform lens-shift OIS as described in Fig. 1 A. The operation and configuration of a sensor-shift OIS utilizes similar requirements, while the actuation module operates to shift a location of the sensor 126 with respect to the lens 122. Actuation module 130 has an actuation module height HM and an actuation module width WM. Actuation module 130 includes a first moving frame 132 having a first moving frame height (“Hi”) and a first moving frame width (“Wi”), a second moving frame 134 having a second moving frame height (“H2”) and a second moving frame width (“W2”) and a static frame 136 having a static frame height (“H3”) and a third static frame width (“W3”). Here, HM = HI + H2 + H3 and WM = W3. First moving frame 132, second moving frame 134 and static frame 136 are all oriented parallel to the x-y plane and parallel to each other. In addition, actuation module 130 includes a first direction actuator (not shown) and a second direction actuator 140. Second direction actuator 140 includes a voice coil motor (“VCM”) including a coil 142, a Hall sensor 144 and a magnet 146. Coil 142 and Hall sensor 144 are fixedly coupled to static frame 136, magnet 146 is fixedly coupled to first moving frame 132.

[0057] The lens 122 typically does not move relative to the first moving frame 132 within the x-y plane, being perpendicular to the optical axis 124. Thus, any movement in the x-y plane, which is imposed on first moving frame 132, and in particular any movement in the x-y plane for performing OIS, causes the lens 122 to follow the movement of the first moving frame 132. Further, the lens may move with respect to the first moving frame 132 and the image sensor 126 along the z direction (parallel to the optical axis 124) for focusing. In some examples, the static frame 136 may be a module housing (or “chassis”) of a camera module (as exemplified in Figs. 3 A-H further below) including actuation module 130 or a part of the module housing or camera module. Generally, the static frame 136 does not move relative to the image sensor 126 and the image sensor 126 does not move relative to the mobile device that includes the camera 120. In other examples, as mentioned above, a sensor-shift OIS may be performed. That is, an image sensor such as image sensor 126 may move for OIS, and a lens such as lens 122 may not move relative to a mobile device including a respective camera. Generally, the image sensor 126 may be formed by a sensor array having a selected number and arrangement of light sensitive pixels.

[0058] In various applications, e.g., directed at mobile cameras or cameras implemented within a mobile electronic device (e.g., a smartphone, a tablet, a smartwatch, etc.), stage heights Hi, H2 and H3 may be in the range of 0.25mm to 2.5mm each. In other examples, Hi, H2 and H3 may be in the range of 0.3mm to 1mm each or in the range of 0.5mm to 1mm. Accordingly, the total height HM may be in the range 0.5mm to 10mm or 1mm to 5mm. Stage width Wi, W2 and W3 may be in the range of 5mm to 50mm each or in the range of 10mm to 30mm each. The stages may be square or rectangular, where stage width relates to both x-y axes of the stages.

[0059] Figs. 1C-E show schematically a top view of camera 120 when performing OIS in a first direction indicated by arrow 148. The second direction is indicated by arrow 149. Fig. 1C, Fig. ID and Fig. IE show the actuation module 130 in a “zero-position”, in a “max-position” and in a “min-position” respectively with respect to the first direction 148. Zero-position means that a movement is performed symmetrically around this position. Max-position and Min- position respectively mean that second moving frame 134 is in a maximum and minimum position with respect to static frame 136 along the first direction.

[0060] Actuation in the first direction 148 is performed by (1) the first direction actuator linearly moving the second moving frame 134 with respect to the static frame 136 in the first direction, while (2) not moving the first moving frame 132 relative to the second moving frame 134. In other words, the first moving frame 132 “rides” on (or is carried by) the second moving frame 134. This leads to a linear movement of the lens 122 in the first direction 148. For example, the first direction actuator may include a VCM to provide an actuation force and two or more ball bearings for transmission of the actuation force and allowing relative motion of the frames.

[0061] Actuation in the second direction 149 is performed by (1) the second direction actuator 140 linearly moving the first moving frame 132 with respect to the second moving frame 134 in the second direction while (2) not moving the second moving frame 134 relative to the static frame 136. This leads to a linear movement of lens 122 in the second direction 149.

[0062] As shown, magnet 146 has a magnet length (“LMI”) given by LMI = LMin + 2S, where “LMin” is a minimum magnet length which is required for actuation in the second direction, and “S” is an excess length that is required due to the relative movement of the static frame 136 and the first moving frame 132. In general, LMin may be in the range of 0.5mm to 15mm or in the range of 1mm to 10mm or in the range of 2.5mm - 10mm, and the excess length S may be in the range of 0.25mm to 5mm to each side of the magnet 146. At each position along the relative movement, the second direction actuator 140 need to be in a position where it is able to provide a sufficient actuation force in the second direction. Accordingly, the excess length S is given by a difference (or change) of a position of coil 142 from a zero position to a maxposition or a min-position respectively. In other words, the smaller the difference between the zero-position to the max-position or the min-position respectively, the smaller the excess length S that is needed. In other examples, instead of adding the excess length S to the magnet 146, the excess length may be added to the coil 142. However, typically a longer coil length is less desired in terms of weight, size, cost and power consumption.

[0063] The use of excess length of magnet 146 or coil 142 results in several drawbacks in the design of the camera module 120 and / or the respective electronic device. Both the magnet 146 and the coil 142 are formed of a relatively dense material, increasing the weight of the resulting product. The use of a large magnet may cause crosstalk into other actuators, for example into a VCM of the first direction actuator or into a focusing actuator, which is undesired. Crosstalk means here, that a position of magnet 146 affects a magnetic measurement performed in another actuator. In conclusion, a shorter magnet / coil length is beneficial in terms of weight, size, cost and magnetic crosstalk prevention.

[0064] Typically, one of the OIS actuators needs a magnet with excess length, while a second actuator, e.g., operating along a second direction 149 may typically use magnet and coil having similar length. This is a result of relative movement of the first frame 132, second frame 134 and statis frame 136 causing relative movement of the magnet 146 with respect to the coil 142. Accordingly, the present disclosure provides a camera module configuration, enabling the use of a smaller magnet (or coil) for operation of at least one OIS actuator. More specifically, the technique and camera module of the present disclosure separate movement of a magnet associated with at least one of the VCM modules, allowing movement of the magnet with respect to the respective moving frame (e.g., first moving frame 132). This eliminates relative movement of the magnet with respect to the coil associated with the VCM, enabling reduction of the magnet size and weight, and thus enabling reduction in weight and costs of the camera module.

[0065] In this connection, Figs. 2A-C schematically illustrate a top view of a camera module 200 including a camera actuator 210 according to some embodiments of the present disclosure. Camera module 200 includes all components and performs all movements of camera 120, except that it includes a modified camera actuator numbered 210.

[0066] Camera actuator 210 comprises a VCM having a coil 212, a Hall sensor 214 and a magnet 216. Coil 212 and Hall sensor 214 are fixedly coupled to the static frame 136. The magnet 216 is fixedly coupled to a stage (not specifically shown here). The stage decouples the magnet 216 from the second moving frame 134 and prevents a movement of the magnet 216 relative to coil 212 and Hall sensor 214 along the first actuation direction (indicated by arrow 148). The stage decouples the movement of the magnet 216 from the second moving frame 134 along the first actuation direction 148, while maintaining a combined movement of the magnet 216 and the first moving frame 132 together relative to coil 212 and Hall sensor 214 along the second actuation direction (indicated by arrow 149). The actuator 210 is configured to actuate movement along the second actuation direction 149, while a second actuator (not specifically shown) is configured to actuate movement along the first actuation direction 148.

[0067] Decoupling movement of the magnet 216 and the second moving frame 134 along the first actuation direction 148 eliminates the need for excess length of the magnet 216. Accordingly, the magnet 216 has a magnet length LM2 = LMin, where “LMin“ is a minimum magnet length that is required for actuating the movement in the second direction together with coil 212. The magnet length LMin may be in the range of 0.5mm to 15mm or in the range of 1mm to 10mm, or in the range of 2.5mm to 10mm, and may be selected in accordance with dimensions of the coil 212. Compared to the magnet 146 exemplified in Figs. 1A to IE, no excess length (2S) is required, as the magnet 216 does not move relative to the static frame 136 and to the first moving frame 132. That is, a magnet length LM2 of magnet 216 is shorter than the magnet length LMI of magnet 146. Still, camera actuator 210 provides a similar actuation force in the second actuation direction 149 as camera actuator 140. A shorter magnet length is beneficial in terms of weight, size, cost and magnetic crosstalk prevention, which may be of high importance in design of handheld devices including a camera module, such as a smartphone, a tablet, a smartwatch, etc.

[0068] Figs. 2A to 2C exemplify movement of the first moving frame 132, generally in response to a second actuator that is not directly illustrated. As a result of decoupling movement of the first moving frame 132 and the magnet 216, the magnet 216 remains in line with the coil 212, enabling the actuator 210 to actuate movement along the second actuation direction 149 regardless of location and / or movement of the first moving frame 132.

[0069] It should be noted that in some conventional camera modules, the coil 142 may be formed with excess length with respect to the magnet 146. When comparing such configurations to the camera module 200 according to the present disclosure, an advantage of camera actuator 210 may be to prevent the need of an excess length added to a coil such as coil 212. A shorter coil length is also beneficial in terms of weight, size, cost and power consumption.

[0070] Reference is further made to Figs. 3 A to 3E illustrating diagrammatic view of camera module 200 according to some embodiments of the present disclosure in different viewpoints. Fig. 3 A shows parts of an embodiment of the camera module 200 including a camera actuator 210 as disclosed herein in a perspective view. Camera module 200 includes a lens 122 having a lens optical axis 124, an image sensor (not shown) and a camera module housing (or “camera module chassis”) 306. Fig. 3B shows a zoom-in (or “magnified”) area of camera module 200 as indicated by circle 308. Fig. 3C shows another zoom-in area of camera module 200. Fig. 3D shows parts of camera module 200 in a cross-sectional view. Fig. 3E shows parts of camera module 300 in another cross-sectional view.

[0071] As shown, the camera module 200 includes an actuator module 210 that has a first moving frame 132, a second moving frame 134, a static frame formed by camera module housing 306 and a magnet stage 318. The first moving frame 132, the second moving frame 134 and the magnet stage 318 are all oriented in a plane parallel to the x-y plane and parallel to each other, and perpendicular to the optical axis 124. The first moving frame 132, the second moving frame 134, the magnet stage 318 and the camera module housing 306 are all configured to move relative to each other in response to operation of the actuator module 210 for actuating components of camera module 200. The actuator module 210 also includes a first direction actuator (not shown) and a second direction actuator 320. Each of the actuators include a VCM for generating actuation force in response to input signals. In this example, actuator module 320 includes a coil 212, and a magnet 216. Optionally, the second direction actuator 320 may include a Hall sensor (not shown) which may not move with respect to the coil 212. Magnet 216 is fixedly coupled to a magnet stage 318. The magnet stage 318 is placed on a static stage 319 (exemplified in Fig. 3D) which is fixedly coupled to the camera module housing 306, and is configured to enable relative movement between the magnet stage 318 and the static stage 319 along the second actuation direction 149. The coil 212 is fixedly coupled to the static stage 319

[0072] The actuator module 210 may also include a set of ball-bearings, e.g., three ball bearing arrangement, a first ball-bearing 315, a second ball-bearing 316 and a second ball-bearing 317 positioned and configured to enable relative movement of the first 132 and second 134 moving frames. The set of three ball-bearings transmits an actuation of second direction actuator 320 along the second direction. Generally, the term ‘ball bearings’ used herein refers to a ball bearing arrangement, which may include a set of rails, and one or more balls positioned within the rails allowing movement of a first rail with respect to a second rail. In some further examples the ball bearings may be replaced by various other configurations allowing relative movement between the first and second moving frames 132 and 134 and the static frame or the camera module housing 306. For example, ball bearings 315, 316 and 317 may be replaced by sliding portions configured with selected grooves utilizing rollers and / or low-friction material, an arrangement of pin and rail, or any other suitable arrangement allowing relative motion of the moving frames along the selected first and second actuation directions.

[0073] The magnet stage 318 and static stage 319 enable a movement of the magnet 216 and the first moving frame 132 together relative to the coil 212 along a second actuation direction (indicated by arrow 149). Generally, the magnet 216 does not move along the first actuation direction 148 and moves along the second actuation direction 149 together with the magnet stage 318. The magnet stage 318 is configured to push the first moving frame 132 transmitting actuation force and moving the first moving frame 132 along the second actuation direction 149. Further, the magnet stage 318 prevents a movement of the magnet 216 relative to the coil 212 along the first actuation direction 148 thus eliminating, or at least significantly reducing misalignment between the magnet 216 and the coil 212 when actuator 210 operates in the first actuation direction 148. The actuator module 210, and specifically the second actuator 320 includes a set of two ball-bearings, a first ball-bearing 340 and a second ball-bearing 350 positioned between the magnet stage 318 and fixed stage 319 and enabling relative movement along the second actuation direction 149. The two ball-bearings may have identical dimensions and components, and they may be located at different sides of the magnet 216 with respect to the first actuation direction as shown in Figs. 3B to 3E. First ball-bearing 340 and second ballbearing 350 may include respectively a linear rail 342 and a linear rail 352 formed by a groove 344 and a groove 354 formed in static stage 319 and a groove 346 and a groove 356 formed in magnet stage 318. Each of the first ball-bearing 340 and the second ball-bearing 350 includes two or more balls, not specifically shown, which can move within the linear rails 342 and 352 respectively. Linear rail 342 and linear rail 352 are parallel to the second actuation direction. The two or more balls moving within linear rail 342 and linear rail 352 enable movement of magnet stage 318 along the second actuation direction. Movement of magnet stage 318 along the first actuation direction is prevented. In other examples, other means may be used for enabling movement of magnet stage 318 along the second actuation direction 149 and preventing movement of magnet stage 318 along the first actuation direction 148. In some examples, a plurality of springs may be used. In other examples, two rails sliding along each other may be used. In yet other examples, a pin sliding in a rail may be used. In yet other examples, a pin sliding in a hole may be used. Further, the magnet and static stages 318 and 319 may be configured with sliding surfaces utilizing a low-friction material allowing sliding motions. In other examples the magnet stage 318 and static stage 319 may be configured with respective grooves utilizing rollers and / or low-friction material. A pin and suitable rail may also be used to allow relative motion between the magnet stage 318 and statis stage 319, the pin and rail may utilize straight pin configuration, circular pin configuration and / or T-shaped pin, and use a corresponding rail structure providing sliding motion in one direction, while restricting motion in the perpendicular direction.

[0074] Additionally, as illustrated in Fig. 3B, the magnet 216 may be configured as having north 216N and south 216S poles thereof facing the coil 212. This enables the VCM to generate an actuation force by transmitting a selected electrical current through the coil 212. Accordingly, the magnet 216 may be formed of an arrangement of magnetic elements, a U- shaped magnet, etc., to provide the desire magnetic field formation. Reference is further made to Figs. 4A-C illustrating schematically a top view of the camera module 200 when performing actuation in the first actuation direction. Fig. 4A, Fig. 4B and Fig. 4C show the second actuator module 320 in a “zero-position” (Fig. 4A), in a “maxposition” (Fig. 4B) and in a “min-position” (Fig. 4C) respectively. Zero-position means that actuation is performed symmetrically around this position. Max-position and Min-position respectively mean that the second moving frame 134 is in a maximum and minimum position with respect to the camera module housing 306 along the first actuation direction, y-axis in this example. As shown, the magnet stage 318 including magnet 216 does not move with respect to the coil 212 and the first moving frame 132.

[0075] Magnet 216 has a magnet length LM2 = LMin, selected in accordance with length of the coil 212. Compared to magnet 146, no excess length (2S) is required, as magnet 216 does not move relative to camera module housing 306 and first moving frame 132. LMin may be in the range of 0.5mm to 15mm, or in the range of 1mm to 10mm, or in the range of 2.5mm to 10mm. That is, the length LM2 of magnet 216 is shorter than the length LMI of magnet 146 used in the conventional actuation modules. Still, second direction actuator 320 provides a similar actuation force in the second actuation direction as the conventional camera actuator 140. As indicated above, A shorter magnet length is beneficial for use in a camera included in a mobile device such as a smartphone in terms of weight, size, cost and magnetic crosstalk prevention.

[0076] Accordingly, as indicated above, the present disclosure provides a camera module using an OIS arrangement for optical image stabilization. The OIS arrangement utilizes a first and second actuators providing actuation along a first and a second actuation directions, shifting position of the lens 122 with respect to the sensor 126 or vice versa. At least one of the actuators (e.g. second actuator) provides decoupling between movement of the moving frame associated with the other actuator (e.g., first actuator), and at least one of magnet and / or coil of the (second) actuator. Such decoupling eliminates, or at least significantly reduced relative movement of the magnet with respect to the coil of the actuator, eliminating the need for excess length of the magnet and / or coil. This in turn enables providing the camera module with reduced weight, cost size, and allows for reducing magnetic crosstalk between elements. All embodiments disclosed herein are beneficial for use in a camera included in a mobile device such as a smartphone, tablet, smartwatch, etc. The camera module may include a lens having a lens optical axis, an effective focal length (“EFL”), typically in the range between 2.5mm to 50mm, and preferably in the range of 5mm to 25mm or 5mm to 15mm. The camera module may also include an image sensor having an image sensor diagonal ("SD”) in the range of 5mm to 30mm, and preferably in the range of 7.5mm to 25mm or 10mm to 20mm. In some examples, such a camera may be a sub-camera which, together with other sub-cameras forms a multicamera (such as a dual-camera) of a mobile device, as known in the art.

[0077] In some embodiments, the actuators disclosed herein may be beneficial for use in a “pop-out camera”, such as e.g. disclosed in the international patent application PCT / IB2020 / 058697, which is incorporated herein by reference in its entirety.

[0078] It is to be noted that the various features described in the various embodiments can be combined according to all possible technical combinations.

[0079] It is to be understood that the disclosure is not limited in its application to the details set forth in the description contained herein or illustrated in the drawings. The disclosure is capable of other embodiments and of being practiced and carried out in various ways. Hence, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception upon which this disclosure is based can readily be utilized as a basis for designing other structures, methods, and systems for carrying out the several purposes of the presently disclosed subject matter.

[0080] Those skilled in the art will readily appreciate that various modifications and changes can be applied to the embodiments of the disclosure as hereinbefore described without departing from its scope, defined in and by the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A camera module, comprising: a lens unit having a lens optical axis and an effective focal length EFL in the range of 2.5mm to 50mm; a camera actuator comprising: a first moving frame, a second moving frame, a static frame, a coil fixedly attached to the static frame, a magnet having a magnet length, and a first set of ball-bearings and a second set of ball-bearings, wherein the camera actuator provides a first actuation of the first moving frame and the second moving frame together and relative to the static frame along a first actuation direction, wherein the first set of ball-bearings is positioned between the first moving frame and the second moving frame and enabling a second actuation along a second actuation direction perpendicular to the first actuation direction, wherein the second set of ball-bearings allows a movement of the magnet and the second moving frame together and relative to the coil along the second actuation direction, and wherein the second set of ball-bearings prevents a movement of the magnet relative to the coil along the first actuation direction.

2. The camera module of claim 1, wherein the magnet and the coil have a substantially similar length along the first actuation direction.

3. The camera module of claim 1 or 2, wherein the camera actuator is operable to actuate the lens for optical image stabilization (OIS), wherein the first actuation direction represents a first OIS direction, wherein the second actuation represents a second OIS direction, and wherein both the first OIS direction and the second OIS direction are perpendicular to the lens optical axis.

4. The camera module of claim 3, wherein the OIS is in an OIS movement range of less than 2.5mm in both the first OIS direction and the second OIS direction.

5. The camera module of claim 3, wherein the OIS is in an OIS movement range of less than 1.5mm in both the first OIS direction and the second OIS direction.

6. The camera module of claim 1, wherein the camera comprises an image sensor having an image sensor normal, wherein the camera actuator is operational to actuate the image sensor for optical image stabilization (OIS), wherein the first actuation direction represents a first OIS direction, wherein the second actuation direction represents a second OIS direction, and wherein both the first OIS direction and the second OIS direction are perpendicular to the image sensor normal.

7. The camera module of claim 6, wherein the OIS is in an OIS movement range of less than 2.5mm in both the first OIS direction and the second OIS direction.

8. The camera module of claim 6, wherein the OIS is in an OIS movement range of less than 1.5mm in both the first OIS direction and the second OIS direction.

9. The camera module of any one of claims 1 to 8, comprising a camera module housing, and wherein at least a part of the camera module housing is the static frame.

10. The camera module of any one of claims 1 to 9, wherein the first moving frame and the second moving frame have a moving frame height HMFI and HMF2 respectively, wherein the static frame has a static frame height HSF, wherein HMFI and HMF2 are in the range of 0.25mm to 2mm and wherein HSF is in the range of 0.25mm to 2.5mm.

11. The camera module of any one of claims 1 to 9, wherein each of the first moving frame and the second moving frame have a moving frame width WMFI and WMF2 respectively, wherein the static frame has a static frame width WSF, wherein WMFI and WMF2 are in the range of 10mm to 40mm and wherein WSF is in the range of 10mm to 40mm.

12. The camera module of any one of claims 1 to 11, wherein the camera actuator is included in an OIS module that has an OIS module height HM in the range of 0.5mm to 5mm.

13. The camera module of any one of claims 1 to 11, wherein the camera actuator is included in an OIS module that has an OIS module width WM in the range of 10mm to 40mm.

14. The camera module of any one of claims 1 to 13, wherein the camera actuator comprises a Hall sensor.

15. The camera module of any one of claims 1 to 14, wherein the EFL is in the range of 2.5mm to 30mm.

16. The camera module of any one of claims 1 to 14, wherein the EFL is in the range of 2.5mm to 15mm.

17. The camera module of any one of claims 1 to 16, wherein the camera is a pop-out camera.

18. The camera module of any one of claims 1 to 17, wherein the camera is included in a mobile device.

19. The camera module of claim 18, wherein the mobile device is a smartphone.

20. The camera module of claim 18, wherein the mobile device is a tablet.

21. A camera module comprising: a lens unit defining an optical axis; a sensor array; a camera actuator comprising a first moving frame, a second moving frame, a static frame, a first actuation motor actuating movement of the first moving frame in a first actuation direction and a second actuation motor actuating movement of the second moving frame in a second actuation direction; wherein the second actuation motor comprises a magnet and a coil operable for generating actuation force; and wherein the magnet and coil are decoupled from movement of the first moving frame along the first actuation direction, and configured to actuate movement of the second moving frame along the second actuation direction.

22. The camera module of claim 21, wherein the magnet and the coil have substantially similar length along the first actuation direction.

23. An electronic device comprising at least one camera module, the at least one camera module comprising: a lens unit defining an optical axis; a sensor array; a camera actuator comprising a first moving frame, a second moving frame, a static frame, a first actuation motor actuating movement of the first moving frame in a first actuation direction and a second actuation motor actuating movement of the second moving frame in a second actuation direction; wherein the second actuation motor comprises a magnet and a coil operable for generating actuation force; and wherein the magnet and coil are decoupled from movement of the first moving frame along the first actuation direction, and configured to actuate movement of the second moving frame along the second actuation direction.

24. The electronic device of claim 23, being a handheld device.

25. The electronic device of claim 23 or 24, being a smartphone or a tablet.

26. An electronic device comprising a camera module, the camera module comprising: a lens unit having a lens optical axis and an effective focal length EFL in the range of 2.5mm to 50mm; a camera actuator comprising: a first moving frame, a second moving frame, a static frame, a coil fixedly attached to the static frame, a magnet having a magnet length, and a first set of ball-bearings and a second set of ball-bearings, wherein the camera actuator provides a first actuation of the first moving frame and the second moving frame together and relative to the static frame along a first actuation direction, wherein the first set of ball-bearings is positioned between the first moving frame and the second moving frame and enabling a second actuation along a second actuation direction perpendicular to the first actuation direction, wherein the second set of ball-bearings allows a movement of the magnet and the second moving frame together and relative to the coil along the second actuation direction, and wherein the second set of ball-bearings prevents a movement of the magnet relative to the coil along the first actuation direction.

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