Patent Publication Number: US-2023156310-A1

Title: Camera module with sensor shifting module

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims the benefit under 35 USC 119(a) of Korean Patent Application No. 10-2021-0156564 filed on Nov. 15, 2021, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. 
     BACKGROUND 
     1. Field 
     The following description relates to a method of implementing optical image stabilization by driving an image sensor. 
     2. Description of Related Art 
     With the development of communications technology, mobile devices, such as smartphones, have been widely distributed. Accordingly, the demand for the functions of a camera included in mobile devices has also increased. For example, a camera included in a mobile device may be designed to provide advanced imaging functions (e.g., an auto-focus function, an anti-shake function, and the like) implemented in a general DSLR camera despite the small size thereof. 
     The optical image stabilization function, that is, an optical image stabilization (OIS) function, may be to prevent image blur from occurring when a camera is shaken during the exposure time, and the OIS function may be desired when imaging in a low-light environment in which a camera is shaken and the exposure time is relatively long. The OIS may include digital IS (DIS), electronic IS (EIS), and optical IS (OIS). Among these functions, optical IS (OIS) may fundamentally prevent image deterioration caused by shaking by correcting an optical path by moving a lens or image sensor in a direction orthogonal to the optical axis. Since a mechanical actuator may be desired, it may be complicated to implement as a device, and although relatively expensive, excellent compensation performance may be obtained. 
     A lens barrel may include an optical system therein, such that a relatively large amount of force may be required to drive the lens barrel. On the other hand, an image sensor may be relatively light and advantageous to implement an excellent OIS function even with a small force. However, when an actuator for driving the image sensor includes a permanent magnet, the magnetic field of the permanent magnet may affect neighboring electronic components. Also, when a mobile device includes a plurality of cameras disposed adjacently to each other, a permanent magnet in each camera may negatively affect the operation of the neighboring cameras, making it functionally difficult to dispose the cameras adjacent to each other or other electronic components in the camera. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     In one general aspect, a sensor shifting module includes a fixed body; a movable body movably, disposed in the fixed body, comprising an image sensor having an imaging plane oriented in a first direction; a substrate, connecting the movable body to the fixed body, configured to deform based on a movement of the movable body with respect to the fixed body; and a driver, configured to move the movable body in a direction orthogonal to the first direction with respect to the fixed body, comprising a driving coil coupled to one of the fixed body and the movable body, and a driving yoke coupled to another of the fixed body and the movable body. The driving yoke is disposed to oppose the driving coil in the direction orthogonal to the first direction. When current is applied to the driving coil, the movable body is configured to move in the direction orthogonal to the first direction by electromagnetic interaction between the driving coil and the driving yoke. 
     The driving yoke may be a soft magnetic material. 
     When no current flows in the driving coil, a magnetic field due to the driving yoke may be zero. 
     The driving coil and the driving yoke may oppose each other in a second direction orthogonal to the first direction, and electromagnetic interaction between the driving coil and the driving yoke may be configured to move the movable body in the second direction. 
     The driving coil and the driving yoke may oppose each other in a second direction orthogonal to the first direction. The driving coil may include a first driving coil and a second driving coil disposed on both sides of the movable body in the second direction, respectively. The driving yoke may include a first driving yoke and a second driving yoke opposing the first driving coil and the second driving coil in the second direction, respectively. 
     The driver may further include a yoke disposed on one side of the driving coil, and the driving coil may be disposed between the driving yoke and the yoke. 
     The driving coil and the driving yoke may oppose each other in a diagonal direction of the image sensor. 
     The substrate may include electrical traces connected to the image sensor. 
     The substrate may include a movable portion fixedly coupled to the movable body, a fixed portion fixedly coupled to the fixed body, and a supporting portion interconnecting the movable portion and the fixed portion to each other. The supporting portion may include a plurality of bridges including the electrical traces embedded therein. 
     The supporting portion may include a guide, disposed between the movable portion and the fixed portion, connected to the movable portion and the fixed portion through the plurality of bridges. 
     The plurality of bridges may further include first bridges extending from the movable portion to the guide in a second direction orthogonal to the first direction, and second bridges extending from the guide to the fixed portion in a third direction orthogonal to the first direction. The second direction and the third direction may intersect each other. 
     The movable body may further include a sensor substrate coupled to the image sensor, the sensor substrate may be disposed on the movable portion, and the sensor substrate and the movable portion may be connected to each other through solder balls at corresponding contact points. 
     The movable body may further include a sensor holder comprising a plate disposed on an upper side of the sensor substrate and an extension portion extending from an edge of the plate, and the driving coil or the driving yoke may be mounted on the extension portion. 
     The driver may further include a position sensor disposed on one of the fixed body and the movable body, and a sensing magnet disposed on another of the fixed body and the movable body and opposing the position sensor in the first direction. 
     In another general aspect, a camera module includes a lens module comprising a lens and a sensor shifting module. The sensor shifting module includes a fixed body; a movable body, movably disposed in the fixed body, comprising an image sensor having an imaging plane oriented in a first direction; a substrate, connecting the movable body to the fixed body, configured to deform based on a movement of the movable body with respect to the fixed body; and a driver, configured to move the movable body in a direction orthogonal to the first direction with respect to the fixed body, comprising a driving coil coupled to one of the fixed body and the movable body, and a driving yoke coupled to another of the fixed body and the movable body. The driving yoke is disposed to oppose the driving coil in the direction orthogonal to the first direction, and a space between the driving yoke and the driving coil is an air gap. 
     The driving yoke may be a soft magnetic material. 
     The substrate may include electrical traces connected to the image sensor. 
     In another general aspect, a sensor shifting module includes: a fixed body; a movable body movably, disposed in the fixed body, comprising an image sensor having an imaging plane oriented in a first direction; a substrate, connecting the movable body to the fixed body, configured to deform based on a movement of the movable body with respect to the fixed body; and drivers configured to move the movable body in orthogonal directions to the first direction, each of the drivers including a driving coil coupled to one of the fixed body and the movable body, and a driving yoke coupled to another of the fixed body and the movable body. A first driver of the drivers and a second driver of the drivers are disposed to oppose each other, and a third driver of the drivers and a fourth driver of the drivers are disposed to oppose each other. 
     Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a diagram illustrating components included in a camera module according to an example embodiment of the present disclosure. 
         FIG.  2    is a diagram illustrating a sensor shifting module according to an example embodiment of the present disclosure. 
         FIG.  3    is a diagram illustrating a substrate on which an image sensor is mounted according to an example embodiment of the present disclosure, viewed from above. 
         FIG.  4    is a diagram illustrating an OIS driver according to an example embodiment of the present disclosure, viewed from above. 
         FIGS.  5 A to  5 D  are diagrams illustrating the movement of a movable body due to the OIS driver in  FIG.  4   . 
         FIG.  6    is a diagram illustrating the example in which unit driving units are disposed in a diagonal direction of a driving direction of an image sensor according to an example embodiment of the present disclosure. 
         FIGS.  7 A to  7 D  are diagrams illustrating the movement of a movable body due to the OIS driving unit in  FIG.  6   . 
         FIGS.  8 A to  8 D  are diagrams illustrating the deformation of a substrate according to the movement of a movable body. 
         FIGS.  9 A and  9 B  are diagrams illustrating a sensor holder having a form different from the example in  FIG.  2 A . 
     
    
    
     Throughout the drawings and the detailed description, the same reference numerals refer to the same or like elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience. 
     DETAILED DESCRIPTION 
     The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be apparent after an understanding of the disclosure of this application. For example, the sequences of operations described herein are merely examples, and are not limited to those set forth herein, but may be changed as will be apparent after an understanding of the disclosure of this application, with the exception of operations necessarily occurring in a certain order. Also, descriptions of features that are known after understanding of the disclosure of this application may be omitted for increased clarity and conciseness. 
     The features described herein may be embodied in different forms, and are not to be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many possible ways of implementing the methods, apparatuses, and/or systems described herein that will be apparent after an understanding of the disclosure of this application. 
     Throughout the specification, when an element, such as a layer, region, or substrate, is described as being “on,” “connected to,” or “coupled to” another element, it may be directly “on,” “connected to,” or “coupled to” the other element, or there may be one or more other elements intervening therebetween. In contrast, when an element is described as being “directly on,” “directly connected to,” or “directly coupled to” another element, there can be no other elements intervening therebetween. 
     As used herein, the term “and/or” includes any one and any combination of any two or more of the associated listed items. 
     Although terms such as “first,” “second,” and “third” may be used herein to describe various members, components, regions, layers, or sections, these members, components, regions, layers, or sections are not to be limited by these terms. Rather, these terms are only used to distinguish one member, component, region, layer, or section from another member, component, region, layer, or section. Thus, a first member, component, region, layer, or section referred to in examples described herein may also be referred to as a second member, component, region, layer, or section without departing from the teachings of the examples. 
     Spatially relative terms such as “above,” “upper,” “below,” and “lower” may be used herein for ease of description to describe one element&#39;s relationship to another element as shown in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, an element described as being “above” or “upper” relative to another element will then be “below” or “lower” relative to the other element. Thus, the term “above” encompasses both the above and below orientations depending on the spatial orientation of the device. The device may also be oriented in other ways (for example, rotated 90 degrees or at other orientations), and the spatially relative terms used herein are to be interpreted accordingly. 
     The terminology used herein is for describing various examples only, and is not to be used to limit the disclosure. The articles “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “includes,” and “has” specify the presence of stated features, numbers, operations, members, elements, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, members, elements, and/or combinations thereof. 
     Due to manufacturing techniques and/or tolerances, variations of the shapes shown in the drawings may occur. Thus, the examples described herein are not limited to the specific shapes shown in the drawings, but include changes in shape that occur during manufacturing. 
     The features of the examples described herein may be combined in various ways as will be apparent after an understanding of the disclosure of this application. Further, although the examples described herein have a variety of configurations, other configurations are possible as will be apparent after an understanding of the disclosure of this application. 
     In the example embodiments, the X-direction, the Y-direction, and the Z-direction may refer to a direction parallel to the X axis, a direction parallel to the Y axis, and a direction parallel to the Z axis, respectively, in the drawings. Also, unless otherwise indicated, the X-direction may include both the +X-axis direction and the −X-axis direction, which may also apply to the Y-direction and the Z-direction. 
     In the example embodiments, two directions (or axes) are parallel to or orthogonal to each other may also include the examples in which the two directions (or axes) are substantially parallel to or substantially side by side to each other. For example, the configuration in which the first axis and the second axis are orthogonal to each other may indicate that the first axis and the second axis may form an angle of 90 degrees or approximate to 90 degrees. 
     “An example embodiment” do not necessarily indicate the same example embodiments. The particular features, structures, or characteristics may be combined in any suitable manner consistent with the example embodiments. 
     In the example embodiments, “configured to” may indicate that a component may include a structure necessary to implement a function. 
     An example embodiment of the present disclosure may enable a camera to provide effective optical image stabilization with low power, or to eliminate or reduce an effect of a magnetic field of an actuator for driving an image sensor on electronic components disposed outside a camera. 
       FIG.  1    is a diagram illustrating components included in a camera module  1  according to an example embodiment. 
     In an example embodiment, the camera module  1  may include a lens module  20 , including at least one lens  21 , a lens barrel  22 , accommodating at least one lens  21 , and an image sensor  11 . Light L may pass through the lens module  20  and reach an imaging plane of the image sensor  11 . The camera module  1  may include an AF driver  23 , which may move the lens module  20  in an optical axis direction to adjust a focal length. The AF driver  23  may include, for example, a coil and a magnet opposing each other. The coil may be fixedly coupled to the lens module  20 , the magnet may be coupled to a fixed body such as a housing, and electromagnetic interaction between the coil and the magnet may allow the lens module  20  to move in the optical axis direction. 
     In an example embodiment, the camera module  1  may provide an optical image stabilization (hereinafter, “OIS”) function. The camera module  1  may provide an OIS function by driving the image sensor  11 . For example, the camera module  1  may include an OIS driver  12  configured to move the image sensor  11  in a direction orthogonal to the optical axis, or to allow the image sensor  11  to rotate about an axis parallel to the optical axis or to rotate about an axis orthogonal to the optical axis. 
     In an example embodiment, the camera module  1  may include a sensor shifting module  10 . The sensor shifting module  10  may include components necessary to implement the OIS function by driving the image sensor  11 . For example, the sensor shifting module  10  may include an image sensor  11  and an OIS driver  12  for driving the image sensor  11 . As another example, the sensor shifting module  10  may refer to only the OIS driver  12 , excluding the image sensor  11 . 
     In an example embodiment, the camera module  1  may further include an optical element in addition to the lens module  20  and the image sensor  11 . In an example embodiment, the camera module  1  may include two or more lens modules. For example, the first optical element  30  and/or the second optical element  40  may be a lens module distinct from the lens module  20 . 
     In an example embodiment, the camera module  1  may include an optical path-changing element disposed in front of the lens module  20 . For example, the first optical element  30  may be implemented as a prism or a mirror. In another example embodiment, the optical path changing element may be disposed between the image sensor  11  and the lens module  20 . For example, the second optical element  40  may be implemented as a prism or a mirror. 
     Hereinafter, the sensor shifting module  100  or the OIS driver  120  described with reference to  FIGS.  2  to  8    may be applied to the camera module  1  in  FIG.  1   . 
       FIG.  2    illustrates a sensor shifting module  100  according to an example embodiment. The sensor shifting module  100  may include an OIS driver  120  that drives the image sensor  111 . In an example embodiment, the OIS driver  120  may include a movable body  110  and a fixed body  130 , including the image sensor  111 . The movable body  110  may be movably disposed in the fixed body  130 . The movable body  110  may be configured to move together with the image sensor  111 . For example, the movable body  110  may include a sensor substrate  112  on which the image sensor  111  is mounted and a sensor holder  113  coupled to the sensor substrate  112 . 
     Referring to  FIG.  2   , the sensor holder  113  may include a plate  113   a  connected to the lower portion of the sensor substrate  112 , and an extension portion  113   b  extending upwardly (in the +Z-direction) from the edge of the plate  113   a . The extension portion  113   b  may oppose the driving coil  122 , and the driving yoke  121  may be seated on the extension portion  113   b . In another example embodiment, the driving yoke  121  may be mounted on the fixed body  130 , and the driving coil  122  may be mounted on the sensor holder  113 . In this case, the driving coil  122  and/or the yoke  123  may be seated on the extension portion  113   b.    
     A signal of the image sensor  111  may be transmitted to another electronic component (e.g., an image signal processor (ISP)) through the sensor substrate  112  and the connector  150 . 
     The fixed body  130  may include a base  131  and components fixedly coupled to the base  131 . For example, the fixed body  130  may include a driving coil  122  and a yoke  123 , to be described later. 
     The movable body  110  may move, through the OIS driver  120 , in a direction orthogonal to the direction in which the imaging plane  111   a  of the image sensor  111  is directed. In an example embodiment, the OIS driver  120  may compensate for the shaking of the camera module  1  or the electronic device on which the image sensor  111  is mounted in a direction orthogonal to the optical axis O. The OIS driver  120  may allow the image sensor  111  to move in a first direction and a second direction orthogonal to the optical axis O. The first direction and the second direction may intersect each other. For example, the OIS driver  120  may allow the movable body  110  to move in the X-direction and/or the Y-direction orthogonal to the Z-axis, thereby compensating for the shaking in the X-direction and/or the Y-direction. 
     In the example embodiments, the direction in which the imaging plane  111   a  of the image sensor  111  is directed may be referred to as an optical axis O direction. That is, the second movable body  110  may move in a direction orthogonal to the optical axis O with respect to the first movable body  130 . In the drawings, the optical axis O may be parallel to the Z axis; accordingly, the Z-direction may refer to a direction parallel to the optical axis O. Also, the X-direction or the Y-direction may refer to a direction orthogonal to the optical axis O. For example, in the example embodiment, the configuration in which the second movable body  110  moves in the X-direction may indicate that the second movable body  110  may move in a direction orthogonal to the optical axis O. For another example, the configuration in which the driving yoke  121  and the driving coil  122  oppose each other in the X-direction may indicate that the driving yoke  121  and the driving coil  122  oppose each other in a direction orthogonal to the optical axis O. Also, the X-direction or the Y-direction may be an example of two directions orthogonal to the optical axis and intersecting each other, and in the example embodiment, the X-direction and the Y-direction may be configured as two directions orthogonal to the optical axis O and intersecting each other. 
     In an example embodiment, the sensor shifting module  100  may include a substrate  140  mechanically connecting the movable body  110  to the fixed body  130 . The substrate  140  may couple the movable body  110  to the fixed body  130  such that the movable body  110  may move in a direction orthogonal to the optical axis with respect to the fixed body  130 . A portion of the substrate  140  may be deformed according to the movement of the movable body  110  with respect to the fixed body  130 . That is, a portion of the substrate  140  may be flexible. When the substrate  140  is deformed, a restoring force may be created in the substrate  140 , and this restoring force may allow the movable body  110  to return to the original position. The movable body  110  in the equilibrium state may move relative to the fixed body  130  as current is applied to the driving coil  122 , and when no current flows in the driving coil  122 , the movable body  110  may move back to the original position by the substrate  140 . 
       FIG.  3    is a diagram illustrating a substrate  140  on which an image sensor  111  is mounted according to an example embodiment, viewed from above. Referring to  FIGS.  2  and  3   , the substrate  140  may include a movable portion  141  on which the sensor substrate  112  is seated, and a fixed portion  142  fixed to the fixed body  130 . The sensor substrate  112  and the movable portion  141  may be electrically connected to each other at corresponding contact points P 1  and P 2  through solder balls. 
     While the movable body  110  (or the image sensor  111 ) moves relative to the fixed body  130 , the movable portion  141  may move relative to the fixed portion  142 . The substrate  140  may include a supporting portion  143  connecting the movable portion  141  to the fixed portion  142 . At least a portion of the supporting portion  143  may be deformed according to a relative movement between the movable portion  141  and the fixed body  130 . For example, the supporting portion  143  may be configured as a flexible substrate. The flexible substrate may be provided in a form in which a conductive pattern (or an electric trace  145 ) is formed in a film formed of a polyimide material. 
     In an example embodiment, the substrate  140  may include a plurality of bridge elements  144  connecting the movable portion  141  to the fixed portion  142 . The plurality of bridge elements  144  may be included in at least a portion of the supporting portion  143 . The plurality of bridge elements  144  may be formed of a flexible material, such that the plurality of bridge elements  144  may be deformed when the movable portion  141  moves relative to the fixed portion  142 . When the movable body  110  moves relative to the fixed body  130 , the movable portion  141  may move relative to the fixed portion  142 , and the bridge elements  144  may be deformed. The restoring force created by the deformation of the bridge elements  144  may allow the movable body  110  or the movable portion  141  to return to the original position. Each of the plurality of bridge elements  144  may include at least one electrical wiring  145 . That is, the plurality of bridge elements  144  may electrically and mechanically connect the movable portion  141  (or the movable body  110 ) to the fixed portion  142  (or the fixed body  130 ). That is, the bridge elements  144  may support the image sensor  111  and may function as a path for transmitting a signal of the image sensor  111 . 
     In an example embodiment, the substrate  140  may include a guide  146  disposed between the movable portion  141  and the fixed portion  142 . For example, the guide  146  may be provided in the form of a picture frame surrounding the movable portion  141 . The fixed portion  142 , the guide  146 , and the movable portion  141  may be connected to each other via the bridge elements  144 . For example, the substrate  140  may include a first bridge  147  extending from the movable portion  141  to the guide  146  and a second bridge  148  extending from the guide  146  to the fixed portion  142 . The first bridge  147  and the second bridge  148  may extend in a direction orthogonal to the optical axis. The first bridge  147  and the second bridge  148  may extend in a direction intersecting each other. For example, the first bridge  147  may extend in the Y-direction, and the second bridge  148  may extend in the Z-direction. 
     Each of the first bridge  147  and the second bridge  148  may include one or more bridge elements  144 .  3 , the first bridge  147  may include four bridge elements  144  extending in the X-direction, and the second bridge  148  may include four bridge elements  144  extending in the Y-direction. The substrate  140  in  FIG.  3    may be an example, and the form of the supporting portion  143  connecting the movable portion  141  to the fixed portion  142  may be varied. For example, the supporting portion  143  may include a plurality of bridge elements  144  extending directly from the movable portion  141  to the fixed portion  142 . As another example, the first bridge  147  or the second bridge  148  may include five bridge elements  144 . The number of bridge elements  144  included in the first bridge  147  or the second bridge  148  may correspond to the number of terminals of the image sensor  111 . 
     The substrate  140  may include an electrical wiring  145  for transmitting a signal of the image sensor  111 . A plurality of bridge elements  144  in the supporting portion  143  may include the electrical wiring  145  embedded therein. The image sensor  111  may be mounted on the sensor substrate  112 , and the sensor substrate  112  may be electrically connected to the fixed portion  142  of the substrate  140 . An electric wiring  145  may extend from each of the contact points P 2  formed in the movable portion  141 . The electrical wiring  145  may extend to fixed portion  142  through bridge element  144 . The electric wiring  145  extending to the fixed portion may be electrically connected to another substrate or electronic component. 
     Meanwhile,  FIG.  3    illustrates the electrical wiring  145  formed on the substrate  140 , and only the electrical wiring  145  extending from some contact points is illustrated for ease of description. 
     Referring to  FIG.  2   , in an example embodiment, the OIS driver  120  may include a position sensor  127 , which may measure how much the movable body  110  moves in a direction orthogonal to the optical axis O. The position sensor  127  may be implemented as a Hall sensor or a magnetoresistance sensor. 
     The OIS driver  120  may include a sensing magnet  124  moving together with the movable body  110  and opposing the position sensor  127 . The position sensor  127  may be disposed to oppose the sensing magnet  124 . For example, the position sensor  127  may be disposed on the base  131 , and the sensing magnet  124  may be disposed on the substrate to oppose the position sensor  127  in the optical axis direction (in the Z-direction). As another example, the position sensor  127  may be disposed on the substrate, and the sensing magnet  124  may be disposed on the base  131 . Two or more of each of the position sensor  127  and the sensing magnet  124  may be provided in pairs. 
     Referring to  FIG.  2   , in an example embodiment, the OIS driver  120  may include a driving coil  122  coupled to one of a movable body  110  and a fixed body  130 , and a driving yoke  121  coupled to the other of the movable body  110  and the fixed body  130 . For example, referring to  FIG.  2   , in an example embodiment, the driving coil  122  and the driving yoke  121  may be coupled to the base  131  and the sensor holder  113 , respectively. The driving yoke  121  and the driving coil  122  may oppose each other in a direction orthogonal to the optical axis O. Electromagnetic interaction between the driving yoke  121 , and the driving coil  122  may allow the movable body  110  to move in a direction orthogonal to the optical axis O with respect to the fixed body  130 . 
     In an example embodiment, the OIS driver  120  may further include a yoke  123  disposed on one side of the coil. The yoke  123  may allow the magnetic field created in the coil to be concentrated only in a direction toward the driving yoke  121 . Since the yoke  123  is disposed on one side of the driving coil  122 , the magnetic field generated by the driving coil  122  may be prevented from affecting the other electronic components or the effect of the magnetic field on the other electronic components may be reduced. 
     In the example embodiments, the driving coil  122  and the driving yoke  121  may be coupled to the fixed body  130  and the movable body  110 , respectively, but an example embodiment thereof is not limited thereto. In another example embodiment, the driving coil  122  and the driving yoke  121  may be coupled to the movable body  110  and the fixed body  130 , respectively. For example, the driving coil  122  and the driving yoke  121  may be coupled to the sensor holder  113  and the base  131 , respectively. 
     An air gap may be formed between the driving coil  122  and the driving yoke  121 . Alternatively, the space between the driving coil  122  and the driving coil  122  may be an air gap. That is, no other member (e.g., a magnet) may be present between the driving coil  122  and the driving yoke  121 . The driving coil  122  and the driving yoke  121  may directly oppose each other with an air gap therebetween. 
       FIG.  2    illustrates the components of the OIS driver  120 , and the example embodiment thereof is not limited to the structure in  FIG.  2   . 
     In an example embodiment, the OIS driver  120  may not include a permanent magnet. In an example embodiment, when no current flows in the driving coil  122 , the magnetic field caused by the driving yoke  121  may be zero or may have a relatively small level. Accordingly, the magnetic field caused by the first OIS driver  120  may be prevented from affecting the other electronic components (e.g., the other electronic components in the camera module  1 , or the electronic components in the other camera module  1 ) or the effect of the magnetic field on the other electronic components may be reduced. 
     In an example embodiment, the driving yoke  121  may be a soft magnetic material. A soft magnetic material has a small coercive force and may be magnetized when exposed to a magnetic field, but when the magnetic field disappears, the soft magnetic material may lose magnetism or may have a relatively low level of magnetism. 
     When current is applied to the driving coil  122 , the driving yoke  121  may be magnetized, such that reluctance force may arise between the driving coil  122  and the driving yoke  121 . An attractive force may be created in a direction in which the driving yoke  121  and the driving coil  122  oppose each other, which may allow the movable body  110  to move in the corresponding direction with respect to the fixed body  130 . For example, referring to  FIG.  4   , when a current is applied to the first driving coil  122 , an attractive force may be created between the first driving coil  122  and the first driving yoke  121 , such that the movable body  110  may move in the −X-direction. Conversely, when a current is applied to the second driving coil  122 , an attractive force may be created between the second driving coil  122  and the second driving yoke  121 , such that the movable body  110  may move in the +X-direction. 
       FIG.  4    is a diagram illustrating an OIS driver according to an example embodiment, viewed from above. 
     The OIS driver  120  may include a plurality of unit drivers  120   a ,  120   b ,  120   c , and  120   d . The unit drivers  120   a ,  120   b ,  120   c , and  120   d  may include a driving yoke  121  and a driving coil  122  opposing each other. The unit drivers  120   a ,  120   b ,  120   c , and  120   d  may further include a yoke  123  disposed on one side of the driving coil  122 . For example, the first unit driver  120   a  may include a first driving yoke  121   a , a first driving coil  122   a , and a first yoke  123   a.    
     Since only attractive force may be created between the driving coil  122  and the driving yoke  121 , at least two unit drivers may be required to move back and forth the movable body  110  in one direction. 
     Referring to  FIG.  4   , the OIS driver  120  may include a first unit driver  120   a  disposed in the −X-direction of the movable body  110 , and a second unit driver  120   b  disposed in the +X-direction of the movable body  110  to correct the shaking in the X-direction. The first unit driver  120   a  may include a first driving yoke  121   a  coupled to the movable body  110  and a first driving coil  122   a  coupled to the base  131 . The first unit driver  120   a  may further include a first yoke  123   a  disposed on one side of the first driving coil  122   a . The second unit driver  120   b  may include a second driving yoke  121   b  coupled to the movable body  110  and a second driving coil  122   b  coupled to the base  131 . The second unit driver  120   b  may further include a second yoke  123   b  disposed on one side of the second driving coil  122   b.    
     Referring to  FIG.  4   , the OIS driver  120  may include a third unit driver  120   c  disposed in the +Y-direction of the movable body  110 , and a second unit driver  120   b  disposed in the +X-direction of the movable body  110  to correct the shaking in the Y-direction. The third unit driver  120   c  may include a third driving yoke  121   c  coupled to the movable body  110  and a third driving coil  122   c  coupled to the base  131 . The third unit driver  120   c  may further include a third yoke  123   c  disposed on one side of the third driving coil  122   c . The fourth unit driver  120   d  may include a fourth driving yoke  121   d  coupled to the movable body  110  and a fourth driving coil  122   d  coupled to the base  131 . The fourth unit driver  120   d  may further include a fourth yoke  123   d  disposed on one side of the fourth driving coil  122   d.    
       FIGS.  5 A to  5 D  are diagrams illustrating the movement of a movable body due to the OIS driver in  FIG.  4   . 
     Referring to  FIG.  5 A , a current may be applied to the first driving coil  122   a  such that the first driving coil  122   a  may pull the first driving yoke  121   a  in the direction of the arrow, and accordingly, the movable body  110  may move in the X-direction. Referring to  FIG.  5 B , a current may be applied to the second driving coil  122   b  such that the second driving coil  122   b  may pull the second driving yoke  121   b  in the direction of the arrow, and accordingly, the movable body  110  may move in the +X-direction. Referring to  FIG.  5 C , a current may be applied to the third driving coil  122   c  such that the third driving coil  122   c  may pull the third driving yoke  121   c  in the direction of the arrow, and accordingly, the movable body may move in the +Y-direction. Referring to  FIG.  5 D , a current may be applied to the fourth driving coil  122   d  such that the fourth driving coil  122   d  may pull the fourth driving yoke  121   d  in the direction of the arrow, and accordingly, the movable body  110  may move in the −Y-direction. 
     2.4. Diagonal Arrangement 
       FIG.  6    is a diagram illustrating the example in which unit driving units  120   a ,  120   b ,  120   c , and  120   d  are disposed in a diagonal direction of a driving direction of an image sensor  111  according to an example embodiment. 
     In an example embodiment, the movable body  110  may move in orthogonal directions to the optical axis. For example, the movable body  110  may move in the X and Y directions. The OIS driver  120  may allow the movable body  110  to move in a first direction OIS-X parallel to the horizontal side  111   c  of the image sensor  111  and a second direction OIS-Y parallel to the vertical side  111   d  of the image sensor  111 . 
     Referring to  FIG.  6   , the unit drivers  120   a ,  120   b ,  120   c , and  120   d  may be disposed in a direction perpendicular to the optical axis O and intersecting two movement directions, OIS-X and OIS-Y, perpendicular to each other. For example, the first unit driver  120   a  and the second unit driver  120   b  may be disposed on both sides of the image sensor  111  in the first diagonal direction D 1 . The third unit driver  120   c  and the fourth unit driver  120   d  may be disposed on both sides of the image sensor  111  in the second diagonal direction D 2 . 
     In an example embodiment, when the OIS driver  120  is configured to move the movable body  110  in the first direction OIS-X and the second direction OIS-Y, the driving coil  122  and the driving yoke  121  may oppose each other in a direction between the first direction OIS-X and the second direction OIS-Y. For example, when the OIS driver  120  is configured to move the movable body  110  in the X-direction and the Y-direction, the driving coil  122  and the driving yoke  121  may oppose each other in directions D 1  and D 2 , forming an angle of 45 degrees with the X-axis or the Y-axis. 
       FIGS.  7 A to  7 D  are diagrams illustrating the movement of a movable body due to the OIS driving unit in  FIG.  6   . 
     Referring to  FIG.  7 A , a current may be applied to the first driving coil  122   a  and the fourth driving coil  122   d  such that the first driving coil  122   a  and the fourth driving coil  122   d  may pull the first driving yoke  121   a  and the second driving yoke  121   b  in the direction of the arrow, respectively, and accordingly, the movable body  110  may move in the −X-direction. Referring to  FIG.  7 B , a current may be applied to the second driving coil  122   b  and the third driving coil  122   c  such that the second driving coil  122   b  and the third driving coil  122   c  may pull the second driving yoke  121   b  and the third driving yoke  121   c  in the direction of the arrow, respectively, and accordingly, the movable body  110  may move in the +X-direction. Referring to  FIG.  7 C , a current may be applied to the first driving coil  122   a  and the third driving coil  122   c  such that the first driving coil  122   a  and the third driving coil  122   c  may pull the first driving yoke  121   a  and the third driving yoke  121   c  in the direction of the arrow, respectively, and accordingly, the movable body  110  may move in the +Y-direction. Referring to  FIG.  7 D , a current may be applied to the second driving coil  122   b  and the fourth driving coil  122   d  such that the second driving coil  122   b  and the fourth driving coil  122   d  may pull the second driving yoke  121   b  and the fourth driving yoke  121   d  in the direction of the arrow, respectively, and accordingly, the movable body  110  may move in the −Y-direction. 
       FIGS.  8 A to  8 D  are diagrams illustrating the deformation of a substrate  140  according to the movement of a movable body  110 . 
     Referring to  FIG.  8 A , when the movable body  110  moves in the −X-direction, the movable portion  141  of the substrate  140  may also move in the −X-direction, and accordingly, the first bridge  147  connecting the guide  146  to the fixed portion  142  may be deformed. Since the bridge elements  144  included in the first bridge  147  have elasticity, the deformed first bridge  147  may provide a restoring force for allowing the movable portion  141  to return in the direction (the +X-direction) opposite to the moving direction. Accordingly, when no current is applied to the OIS driver  120 , the movable portion  141  may move in the −X-direction. 
     Referring to  FIG.  8 B , when the movable body  110  moves in the +X-direction, the movable portion  141  of the substrate  140  may also move in the +X-direction, and accordingly, the first bridge  147  connecting the guide  146  to the fixed portion  142  may be deformed. Since the bridge elements  144  included in the first bridge  147  have elasticity, the deformed first bridge  147  may provide a restoring force to allow the movable portion  141  to return in the direction (the −X-direction) opposite to the moving direction. 
     Referring to  FIG.  8 C , when the movable body  110  moves in the +Y-direction, the movable portion  141  of the substrate  140  may also move in the +Y-direction, and accordingly, the second bridge  148  connecting the guide  146  to the fixed portion  142  may be deformed. Since the bridge elements  144  included in the second bridge  148  have elasticity, the deformed second bridge  148  may provide a restoring force to allow the movable portion  141  to return in the direction (the −Y-direction) opposite to the moving direction. 
     Referring to  FIG.  8 D , when the movable body  110  moves in the −Y-direction, the movable portion  141  of the substrate  140  may also move in the −Y-direction, and accordingly, the second bridge  148  connecting the guide  146  to the fixed portion  142  may be deformed. Since the bridge elements  144  included in the second bridge  148  have elasticity, the deformed second bridge  148  may provide a restoring force to allow the movable portion  141  to return in the direction (the +Y-direction) opposite to the moving direction. 
       FIGS.  9 A and  9 B  are diagrams illustrating a sensor holder  213  having a form different from the example in  FIG.  2 A . 
     Referring to  FIG.  9 A , the sensor holder  213  may be disposed on the sensor substrate  112 . In an example embodiment, the sensor holder  213  may include a plate  213   a  disposed on the sensor substrate  112  and an extension portion  213   b  extending downwardly (in the −Z-direction) from the edge of the plate  213   a . The extension portion  213   b  may oppose the driving coil (e.g., the driving coil  122  in  FIG.  2   ) of the OIS driver  120 , and the driving yoke (e.g., the driving yoke  121  in  FIG.  2   ) of the OIS driver  120  may be seated on the extension portion  213   b . In another example embodiment, the driving yoke may be mounted on the fixed body  130  and the driving coil may be mounted on the sensor holder  213 . In this case, the driving coil and/or yoke (e.g., the yoke  123  in  FIG.  2   ) may be seated on the extension portion  213   b . As compared to the sensor holder  213  in  FIG.  2   , the sensor holder  213  in  FIG.  9    may be more advantageous in avoiding interference with the solder ball connecting the sensor substrate  112  to the substrate  140 . Also, when the sensor holder  213  is disposed on the upper side of the sensor substrate  112 , a thickness of the sensor holder  213  may be relatively freely increased, which may improve the mechanical rigidity of the sensor holder  213 . 
     Referring to  FIG.  9 A , the image sensor  111  may be electrically connected to the sensor substrate  112  through a conductive via. 
     Referring to  FIG.  9 B , the sensor holder  313  may be disposed on the sensor substrate  112 . In an example embodiment, the sensor holder  313  may include a plate  313   a  disposed on the sensor substrate  112  and an extension portion  313   b  extending downwardly (in the −Z-direction) from the edge of the plate  313   a . The extension portion  313   b  may oppose the driving coil (e.g., the driving coil  122  in  FIG.  2   ) of the OIS driver  120 , and the driving yoke (e.g., the driving yoke  121  in  FIG.  2   ) of the OIS driver  120  may be seated on the extension portion  313   b . In another example embodiment, the driving yoke may be mounted on the fixed body  130 , and the driving coil may be mounted on the sensor holder  313 . In this case, the driving coil and/or yoke (e.g., the yoke  123  in  FIG.  2   ) may be seated on the portion  313   b . As compared to the sensor holder  313  in  FIG.  2   , the sensor holder  313  in  FIG.  9    may be more advantageous in avoiding interference with the solder ball connecting the sensor substrate  112  and the substrate  140 . Also, when the sensor holder  313  is disposed on the upper side of the sensor substrate  112 , a thickness of the sensor holder  313  may be relatively freely increased, which may improve the mechanical rigidity of the sensor holder  313 . 
     Referring to  FIG.  9 B , the image sensor  111  may be directly mounted on the sensor substrate  112 . Accordingly, the sensor holder  313  may include a through portion  313   c  in a portion corresponding to the image sensor  111 . The image sensor  111  may be seated on the sensor substrate  112 , and a terminal of the image sensor  111  and a terminal of the sensor substrate  112  may be connected to each other through wire bonding. 
     According to the aforementioned example embodiments, the camera may provide effective optical image stabilization with low power. Also, according to an example embodiment, the effect of the magnetic field of the actuator driving the image sensor on the electronic component disposed outside the camera may be eliminated or reduced. 
     While this disclosure includes specific examples, it will be apparent after an understanding of the disclosure of this application that various changes in form and details may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only, and not for purposes of limitation. Descriptions of features or aspects in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the disclosure is defined not by the detailed description, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.