Actuator for camera

Abstract

An actuator for a camera according to an embodiment of the present invention comprises: a first frame moving in a planar direction perpendicular to an optical axis; first and second magnets installed on the first frame so as to form a right angle with each other; a second frame supporting the movement of the first frame; a first yoke comprising a first part and a second part spaced apart from the first part along the longitudinal direction of the first magnet and disposed at a position closer to the second magnet than the first part, the first yoke being disposed so as to face the first magnet; and a second yoke comprising a third part and a fourth part spaced apart from the third part along the longitudinal direction of the second magnet and disposed at a position closer to the second magnet than the third part, the second yoke being disposed so as to face the second magnet. At least one of the second part and the fourth part is characterized by being smaller in size than the other parts.

Description

Actuator for camera

[0001] The present invention relates to an actuator for a camera, and more specifically, to an actuator for a camera that can further improve the driving precision of OIS by more effectively correcting the rotational component of the carrier.

[0002] As hardware technology for image processing advances and user demand for video recording increases, features such as autofocus (AF) and optical image stabilization (OIS) are being implemented not only in standalone camera devices but also in camera modules mounted on mobile terminals such as mobile phones and smartphones.

[0003] The autofocus function refers to a feature that enables a sharp image to be generated on an image sensor (CMOS, CCD, etc.) located behind the lens by linearly moving a carrier equipped with a lens or similar device along the optical axis to adjust the focal distance to the subject.

[0004] Image stabilization refers to a function that improves image clarity by adaptively moving the carrier equipped with the lens (or image sensor) in a direction that compensates for shake caused by hand tremor in the event of shaking of the lens or image sensor.

[0005] One of the representative methods for implementing autofocus or OIS functions is to install a magnet (coil) on a moving body (carrier) and a coil (magnet) on a stationary body (housing, base, or other types of carrier, etc.), and then move the moving body in the direction of the optical axis or in a direction perpendicular to the optical axis by generating a driving force between the coil and the magnet.

[0006] OIS corrects shaking by moving a moving body equipped with a lens or image sensor in the first direction or / and a second direction, which are two axes on a plane perpendicular to the optical axis, relative to a relative fixed body.

[0007] In the case of conventional actuators, a structure is mainly applied in which an intermediate moving body (middle guide) is applied between a moving body and a stationary body for independent movement in the first and second directions, and balls are placed between the moving body and the intermediate moving body, and between the intermediate moving body and the stationary body, respectively.

[0008] In the case of such conventional actuators, the structure consists of a stacked moving body, an intermediate moving body, and a stationary body, and since balls are placed between them, the height increases with respect to the optical axis direction.

[0009] Since camera actuators are installed in an upright position on the main board of a mobile terminal such as a smartphone, an increase in the height of the actuator implies an increase in the thickness of the mobile terminal; therefore, conventional actuators have the problem of failing to meet the trend of slimming down mobile terminals and having low space utilization.

[0010] To resolve these problems, a structure is disclosed that moves a moving body in a plane perpendicular to the optical axis with respect to a relative fixed body without an intermediate moving body. An actuator with this structure has the advantage of being able to reduce the height of the actuator because it only requires placing balls between the moving body and the relative fixed body, without stacking two types of balls that guide movement in each direction vertically.

[0011] However, in the case of such actuators, since there is no structure to guide the linear movement of the moving body, the moving body may rotate when various causes, such as external forces, are applied. Since OIS is implemented by linearly moving the moving body, on which the lens is mounted, in a combined direction of the first and second directions, the driving precision of the OIS may be degraded when the moving body rotates in this manner.

[0012] The present invention was devised to solve the aforementioned problems against the background described above, and aims to provide a camera actuator capable of improving the precision of linear control for hand shake correction by effectively suppressing the rotation of a moving body caused by external forces, etc., and inducing the rotated moving body to quickly return to its original position.

[0013] Other objects and advantages of the present invention may be understood from the description below and will become more clearly known from the embodiments of the present invention. Furthermore, the objects and advantages of the present invention may be realized by the configurations set forth in the claims and combinations thereof.

[0014] An actuator for a camera according to an embodiment of the present invention for achieving the above objective may include: a first frame that moves in a plane direction perpendicular to the optical axis; first and second magnets installed on the first frame to form a right angle; a second frame that supports the movement of the first frame; a first yoke that is positioned to face the first magnet, comprising a first part and a second part that is spaced apart from the first part along the length direction of the first magnet and positioned closer to the second magnet than the first part; and a second yoke that is positioned to face the second magnet, comprising a third part and a fourth part that is spaced apart from the third part along the length direction of the second magnet and positioned closer to the second magnet than the third part.

[0015] In this case, one or more of the second and fourth parts of the present invention may be configured to be smaller in size than other parts other than themselves, and according to an embodiment, the second and fourth parts of the present invention may be configured to be smaller in size than the first and third parts.

[0016] In addition, the second and fourth parts of the present invention may be configured to have the same size as each other, and in this case, it is preferable that the first and third parts of the present invention be configured to have the same size as each other.

[0017] According to an embodiment, the second part of the present invention may be smaller in size than the first, third, and fourth parts, and in this case, the first, third, and fourth parts may have the same size as each other.

[0018] According to an embodiment, the fourth part of the present invention may be smaller in size than the first, second, and third parts, and in this case, the first, second, and third parts may have the same size as each other.

[0019] Preferably, an actuator for a camera according to one embodiment of the present invention may further include first and second coils that are arranged to face the first magnet at different positions and drive independently; and third and fourth coils that are arranged to face the second magnet and drive in conjunction.

[0020] In this case, one of the third and fourth coils of the present invention has a width facing the second magnet that is smaller than the other, and it is preferable that the coil among the third and fourth coils with a smaller width facing the second magnet be positioned at a location corresponding to the fourth part.

[0021] According to one embodiment of the present invention, since OIS is implemented without the addition of a middle guide or other equivalent additional configuration, the structure and shape of the entire actuator can be configured in a more space-intensive form, which can be further optimized for slimming down mobile terminals.

[0022] According to one embodiment of the present invention, by applying a structural arrangement that allows for positional alignment between the yoke and the magnet and the application of optimized torque, the rotation of the moving body can be effectively suppressed, and the restoration of the moving body to its correct position can be induced more effectively.

[0023] According to one embodiment of the present invention, the coil section for correcting rotational components is composed of a plurality of coils that drive independently, and the coil section for increasing driving force is composed of a plurality of coils that drive in conjunction, thereby increasing the precision and efficiency of both the basic driving and the driving for rotational correction of the OIS.

[0024] According to one embodiment of the present invention, by differentiating the size of a yoke placed in an adjacent area and a yoke placed in a different area, the influence of the magnetic field can be minimized, thereby enabling more precise implementation of rotation suppression, etc.

[0025] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to facilitate a more effective understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in these drawings.

[0026] FIGS. 1 and 2 are drawings illustrating the overall configuration of a camera actuator according to a preferred embodiment of the present invention.

[0027] FIG. 3 is a drawing illustrating a configuration for driving the movement of the first frame,

[0028] FIG. 4 is a cross-sectional view illustrating the internal structure of a camera actuator according to an embodiment of the present invention.

[0029] FIG. 5 is a diagram illustrating the interrelationship between a coil, a magnet, and a position sensor (Hall sensor).

[0030] FIG. 6 is a drawing illustrating an embodiment of a second coil and a second Hall sensor according to the present invention.

[0031] FIG. 7 is a drawing illustrating a yoke according to an embodiment of the present invention,

[0032] FIG. 8 is a bottom view illustrating the positional relationship between the magnet and the yoke,

[0033] FIGS. 9 to 11 are drawings illustrating a yoke according to another embodiment of the present invention.

[0034] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, and should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0035] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0036] FIGS. 1 and 2 are drawings illustrating the overall configuration of a camera actuator (hereinafter referred to as 'actuator') (1000) according to the present invention; FIGS. 3 is a drawing illustrating the configuration for driving the movement of a first frame (200); FIGS. 4 is a cross-sectional view illustrating the internal structure of an actuator (1000) according to an embodiment of the present invention; FIGS. 5 is a drawing illustrating the mutual relationship between a coil, a magnet, and a position sensor (Hall sensor); and FIGS. 6 is a drawing illustrating an embodiment of a second coil and a second Hall sensor according to the present invention.

[0037] First, the overall configuration of the present invention and the operational relationship in which AF and OIS are performed will be explained with reference to FIGS. 1 to 6, etc., and detailed information regarding the yoke of the present invention, which performs the rotation suppression and position restoration functions of the first frame (200) that is the moving body of OIS, will be described later.

[0038] The actuator (1000) of the present invention illustrated in FIG. 1 and the drawings attached below is an embodiment in which AF and OIS are implemented together, but it is obvious that the actuator (1000) of the present invention can be implemented as an actuator for OIS only depending on the embodiment.

[0039] In addition, the actuator (1000) of the present invention can be implemented as a standalone device, and can also be implemented in the form of a camera module including an image sensor (not shown), etc.

[0040] As illustrated in FIG. 1, etc., the actuator (1000) of the present invention may be configured to include a first frame (200), a second frame (100), and a housing (300).

[0041] The Z-axis direction shown in Fig. 1, etc. is the optical axis direction in which light enters the lens or lens assembly (L), and corresponds to the direction in which the second frame (second carrier) (100) moves back and forth when AF is driven, and the X-axis and Y-axis perpendicular to the optical axis correspond to the direction in which the first frame (first carrier) (200) moves when OIS is driven.

[0042] In the following description of the embodiments of the present invention, one of the two directions perpendicular to the optical axis is referred to as the first direction (Y-axis direction) and the other as the second direction (X-axis direction); however, this is merely an example based on a relative perspective, and it is obvious that either the X-axis direction or the Y-axis direction may be the first direction and the other direction may be the second direction.

[0043] It is self-evident that the axis depicted in the drawing, the term referring to the axis, and terms such as upper, lower, front, rear, vertical, horizontal, etc., described with respect to the axis, are intended merely to provide a relative standard for describing the embodiments of the present invention and are not intended to specify any direction or position based on an absolute standard; furthermore, it is obvious that they may vary relatively depending on the position of the object to be examined, the position or direction of view, etc.

[0044] The housing (300) of the present invention corresponds to a basic frame structure that accommodates internal components of an actuator (1000) according to the present invention, and may be combined with a case (600) that functions as a shield can depending on the embodiment.

[0045] The first frame (200) corresponds to an OIS carrier or OIS frame that moves on a plane perpendicular to the optical axis (XY plane based on the drawing) with the second frame (100) or housing (300) as a relative fixed body. When a lens or image sensor is mounted on this first frame (200), the lens (L), etc. moves due to the movement of the first frame (200), thereby implementing an OIS that eliminates external disturbances such as hand shake.

[0046] The first ball (B1) can be placed between the first frame (200) and the second frame (100). If AF is not integrally implemented, the first ball (B1) can be placed between the first frame (200) and, for example, the housing (300), which corresponds to a relative fixed body of the first frame (200).

[0047] In this manner, when the first ball (B1) is provided, an appropriate gap is maintained between the first frame (200) and the second frame (100), and the first frame (200) can move more flexibly due to the minimized frictional force caused by the moving and rolling of the first ball (B1), thereby further improving noise reduction, driving force minimization, and driving precision.

[0048] One or more of the second frame (100) and the first frame (200) may include a pocket portion that accommodates the first ball (B1) and prevents the first ball (B1) from escaping to the outside.

[0049] A first magnet (M1) facing the first coil section (C1) and a second magnet (M2) facing the second coil section (C2) may be installed in the first frame (200). For directional control, it is preferable that the first and second magnets (M1, M2) be arranged to be perpendicular to each other.

[0050] When power of an appropriate size and direction is supplied to the first coil part (C1) through the control of the first drive drive (D1), a magnetic force (electromagnetic force) is generated between the first magnet (M1) installed on the first frame (200) and the first coil part (C1), and using this generated magnetic force as a driving force, the first frame (200) moves in the first direction (Y-axis direction) relative to the second frame (100) or the housing (300). Through this movement control, external disturbances such as hand tremors in the Y-axis direction are corrected.

[0051] When power of an appropriate size and direction is supplied to the second coil section (C2) through the control of the second drive (D2), a magnetic force (electromagnetic force) is generated between the second magnet (M2) installed on the first frame (200) and the second coil section (C2), and using this generated magnetic force as a driving force, the first frame (200) moves the second frame (100) or the housing (300) relative to the fixed body in the second direction (X-axis direction). Through this movement control, X-axis direction OIS is implemented.

[0052] According to the embodiment, position sensors (H1, H2) that detect the position, direction of movement, size of movement, etc. of the first frame (200) may be further included. When the position sensors detect the position, etc. of the first frame (200) and transmit a corresponding signal to the drive drive (control unit), the drive drive controls the supply of power of a size and direction corresponding to the signal to the coil unit.

[0053] The above position sensor can be implemented as a Hall sensor that uses the Hall effect to detect changes in the magnitude and / or direction of the magnetic field of a magnet present within the detection area and outputs an electrical signal accordingly.

[0054] The first Hall sensor (first position sensor) (H1) of the present invention is configured to detect the magnitude of a magnetic field that changes according to the position of the first magnet (M1) and to output a corresponding signal.

[0055] When the first Hall sensor (H1) detects the position of the first magnet (M1) installed on the first frame (200) and outputs a corresponding signal to the first drive drive (D1), the first drive drive (D1) controls the supply of power of a corresponding size and direction to the first coil part (C1).

[0056] The first Hall sensor (H1) may include a plurality of Hall sensors (H1A, H1B) positioned to face the first magnet (M1) at different locations so as to effectively detect the rotational component of the first frame (200).

[0057] As an example of this, FIG. 5 shows a left Hall sensor (H1A) facing the left part (M1A) of the first magnet (M1) (based on FIG. 5) and a right Hall sensor (H1B) facing the right part (M1B) of the first magnet (M1).

[0058] Correspondingly, the first drive drive (D1) may also include a plurality of drive drives (D1A, D1B), and the first coil part (C1) may also include a plurality of coils (C1A, C1B) that are independently controlled by each of the first drive drives (D1A, D1B).

[0059] For the relative distinction of the coils, the coils included in the first coil section (C1) are referred to as the first coil (C1A) and the second coil (C1B).

[0060] When a rotational component of the first frame (200) is detected through detection by multiple first Hall sensors (H1A, H1B), each of the first drive drives (D1A, D1B) controls the magnitude of the current supplied to the first coil (C1A) and the second coil (C1B) so that the rotational component of the first frame (200) can be corrected.

[0061] If the magnitude of the magnetic field detected by multiple first Hall sensors (H1A, H1B) is the same, this means that the first magnet (M1), i.e., the first frame (200), moves linearly or maintains its position.

[0062] In contrast, if the magnitude of the magnetic field detected by multiple first Hall sensors (H1A, H1B) is different from each other, this means that there is an attitude deformation due to a rotational component in the first frame (200).

[0063] In order to more effectively correct the rotational component of the first frame (200), it is preferable that the first coil (C1A), which is one of the first coil parts (C1), is controlled by the first Hall sensor (H1A) and the first drive (D1A), and the second coil (C1B), which is the other of the first coil parts (C1), is controlled by the first Hall sensor (H1B) and the first drive (D1B). That is, it is preferable that the first coil (C1A) and the second coil (C1B) be configured to be driven or controlled independently.

[0064] The second Hall sensor (second position sensor) (H2) of the present invention is configured to detect the magnitude of a magnetic field that changes according to the position of the second magnet (M2) and output a corresponding signal.

[0065] In order to increase the precision of detecting the rotational component of the first frame (200) or to supplement or complement the detection of the rotational component of the first frame (200), the second Hall sensor (H2) may also be implemented as a plurality of Hall sensors, similar to the first Hall sensor (H1). According to the embodiment, as illustrated in the drawing, the detection of the rotational component of the first frame (200) may be configured to be implemented in either the first Hall sensor (H1) or the second Hall sensor (H2).

[0066] When the second Hall sensor (H2) detects the position of the second magnet (M2) installed on the first frame (200) and outputs a corresponding signal to the second drive drive (D2), the second drive drive (D2) can control power of a size and direction corresponding to this to be cyclically supplied to the second coil part (C2).

[0067] As illustrated in the drawing, it is preferable for the second coil section (C2) to include multiple coils to increase driving efficiency and driving force. For relative distinction of the coils, the coils included in the second coil section (C2) are referred to as the third coil (C2B) and the fourth coil (C2A).

[0068] It is preferable that the first coil (C1A) and the second coil (C1B) of the first coil section (C1) are arranged to face the first magnet (M1) at different locations and drive independently, and the third coil (C2B) and the fourth coil (C2A) of the second coil section (C2) are arranged to face the second magnet (M2) at different locations and drive in conjunction.

[0069] According to the embodiment of the present invention, the first direction (Y-axis direction) OIS of the first frame (200) is implemented by the first coil part (C1) and the first magnet (M1), and the second direction (X-axis direction) OIS of the first frame (200) is implemented by the second coil part (C2) and the second magnet (M2). In addition, rotation correction of the first frame (200) can be implemented through independent control of the first coil (C1A) and the second coil (C1B) of the first coil part (C1), and the driving force of the second direction OIS can be increased through multiple coils.

[0070] For example, when a clockwise rotation component of the first frame (200) is detected, the magnitude of the current applied to the second coil (C1B) can be controlled to be relatively larger than the magnitude of the current applied to the first coil (C1A) so that the rotation component of the first frame (200) is corrected.

[0071] Depending on the embodiment, the clockwise rotation component of the first frame (200) may be corrected by controlling such that an attractive force is generated between the first coil (C1A) and the first magnet (M1), and a repulsive force is generated between the second coil (C1B) and the second magnet (M2).

[0072] When multiple coils included in the second coil section (C2) are controlled to be interconnected, that is, so that the driving force has the same directionality, it may be desirable to configure the size of the third coil (C2B) facing the second magnet (M2) and the size of the fourth coil (C2A) facing the second magnet (M2) differently from each other, as exemplified in FIG. 6.

[0073] Since a specific area at both ends of the magnet corresponds to a variable region where the magnitude of the magnetic field changes significantly, it is difficult to implement drive control linearly. Therefore, by configuring individual coils such that the size or width facing the magnet is differentiated, the variable region of the magnet facing the individual coil can be excluded as much as possible, thereby improving both driving force enhancement and linear control characteristics.

[0074] In this case, the second Hall sensor (H2) facing the second magnet (M2) is preferably positioned in the inner space of the third coil (C2B) as shown in FIG. 9, but is positioned in a location biased in the direction in which the fourth coil (C2A) is positioned.

[0075] In the case of the actual configuration of the present invention, even if the first frame (200) rotates due to external factors, the second Hall sensor (H2) can be positioned to face the area of ​​the second magnet (M2) where the change in position or orientation is relatively smallest. Therefore, the magnetic field of the second magnet (M2) can be detected in an environment where the influence of the rotation of the first frame (200) is minimized, thereby improving the driving precision of rotation detection and rotation correction.

[0076] The second frame (100) corresponds to a moving body that implements AF by moving the housing (300) in the direction of the optical axis (Z-axis direction) as a relative fixed body.

[0077] In order to guide the movement of the second frame (100) in the direction of the optical axis, one or more of the second frame (100) and the housing (300) may be provided with a rail (R) having a shape extended in the direction of the optical axis and on which the second ball (B2) is placed.

[0078] A third magnet (M3) is installed in the second frame (100) and faces an AF coil (C3) installed in the housing (300). When power of an appropriate size and direction is supplied to the AF coil (C3) through detection by the AF Hall sensor (H3) and control by the AF drive (D3), an electromagnetic force (magnetic force) is generated between the AF coil (C3) and the third magnet (M3), and the second frame (100) moves in the direction of the optical axis using this electromagnetic force as a driving force.

[0079] When the second frame (100) moves in the direction of the optical axis, the first frame (200), on which the lens, etc. is mounted, also moves in the direction of the optical axis together with the second frame (100).

[0080] When the second frame (100) moves back and forth in the direction of the optical axis in this way, the distance between the lens and an image sensor (not shown), such as a CCD (Charged-coupled Device) or CMOS (Complementary Metal-oxide Semiconductor), which is provided at the rear end (relative to the direction of the optical axis) of the actuator (1000), is adjusted, thereby implementing an autofocus function or a zoom function.

[0081] The actuator (1000) of the present invention may include a third magnet (M3) and a yoke plate (500) that generates a force, provided in a housing (300).

[0082] As the second frame (100) mediated by the second ball (B2) is pulled in the direction of the housing (300) (in the Y-axis direction according to the drawing) by the attractive force between the yoke plate (500) and the third magnet (M3), point contact between the second ball (B2) and the second frame (100) and between the second ball (B2) and the housing (300) is continuously maintained.

[0083] To effectively implement linear guiding, it is preferable that the second ball (B2) be provided in a form in which a portion thereof is received in a rail (R) formed in one or more of the second frame (100) and the housing (300).

[0084] In this way, when the second ball (B2) is positioned between the second frame (100) and the housing (300), the second frame (100) can move more flexibly linearly with minimized frictional force caused by the moving, rolling, etc. of the second ball (B2).

[0085] It is preferable that the circuit board (400), on which coils (C1, C2, C3) and Hall sensors (H1, H2, H3) are mounted, be provided in a housing (300) located at the outermost side of the actuator (1000) for interfacing with an external device.

[0086] The first drive (D1A, D1B) may be implemented as independent electronic components or devices, but it may also be implemented in the form of a single electronic component (chip) integrated with the first Hall sensor (H1A, H1B) through an SOC (System On Chip). In this regard, the drawing shows the first Hall sensor (H1A) and the first drive (D1A), and the first Hall sensor (H1B) and the first drive (D1B) in the same configuration. The second drive (D2) and / or the AF drive (D3) are also like this.

[0087] The drive unit may be provided in the same number as the individual Hall sensors and implemented as a single chip with the individual Hall sensors, but depending on the embodiment, it may not be provided in the same number as the individual Hall sensors through channel adjustment for electrical connection with the Hall sensors, and may be implemented as a single chip with some of the individual Hall sensors.

[0088]

[0089] FIG. 7 is a drawing illustrating a yoke (700A, 700B) according to one embodiment of the present invention, FIG. 8 is a bottom view illustrating the positional relationship between a magnet (M1, M2) and a yoke (700A, 700B), and FIG. 9 to 11 are drawings illustrating a yoke according to another embodiment of the present invention.

[0090] Hereinafter, with reference to the attached drawings, etc., the specific functions and structures of the yoke (700A, 700B) according to embodiments of the present invention will be described in detail.

[0091] The yoke of the present invention is configured to be installed on the second frame (100), which is a relative fixed body of the first frame (200), and generates an attractive force with the magnets (M1, M2) installed on the first frame (200).

[0092] Specifically, the yoke may include a first yoke (700A) and a second yoke (700B). The first yoke (700A) is installed on the second frame (100) to face the first magnet (M1) and is made of a magnetic body or magnetic material, etc., that generates an attractive force with the first magnet (M1). The second yoke (700B), made of a magnetic material, etc., is installed on the second frame (100) to face the second magnet (M2) and generates an attractive force with the second magnet (M2).

[0093] As previously described, a first ball (B1) is positioned between the first frame (200), which is the moving body of the OIS, and the second frame (100), which is the relative fixed body of the first frame (200), and an attractive force is applied between the first frame (200) and the second frame (100) by the yoke (700A, 700B) and the magnet (M1, M2).

[0094] Therefore, the first frame (200) is in close contact with the second frame (100) in the direction of the second frame (100) (Z-axis direction based on the drawing) while the first ball (B1) is mediated between the first frame (200) and the second frame (100), so physical contact is maintained between the first frame (200) and the first ball (B1), as well as between the first ball (B1) and the second frame (100).

[0095] As illustrated in FIG. 7, the first yoke (700A) may specifically include a first part (710A) and a second part (720A) spaced apart along the longitudinal direction (X-axis direction based on the drawing) of the first magnet (M1).

[0096] In this regard, the second yoke (700B) may include a third part (720B) and a fourth part (710B) spaced apart along the longitudinal direction (Y-axis direction based on the drawing) of the second magnet (M2).

[0097] In this way, when the yoke (700A, 700B) is composed of multiple separated parts, the position where the torque is applied and the magnitude of the torque at each position can be reflected, thereby enabling more effective suppression of rotation and restoration of the correct position of the first frame (200).

[0098] The first part (710A) and the second part (720A) of the first yoke (700A) both face the first magnet (M1) and are installed on the relative fixed body (second frame (100), etc.) of the first frame (200) in a manner spaced apart from each other along the longitudinal direction of the first magnet (M1) as shown in the drawing.

[0099] For relative distinction, the part positioned closer to the second magnet (M2) among the separated multiple parts of the first yoke (700A) is referred to as the second part (720A).

[0100] The third part (720B) and the fourth part (710B) of the second yoke (700B) both face the second magnet (M2) and are installed on the relative fixed body (second frame (100), etc.) of the first frame (200) in a form spaced apart from each other along the longitudinal direction of the second magnet (M1) as shown in the drawing.

[0101] For relative distinction, among the multiple parts included in the second yoke (700B), the part positioned closer to the first magnet (M1) is referred to as the fourth part (710B).

[0102] According to this relative distinction, among the first part (710A) of the first yoke (700A), the second part (720A) of the first yoke (700A), the third part (720B) of the second yoke (700B), and the fourth part (710B) of the second yoke (700B), the second and fourth parts (720A, 710B) correspond to parts (hereinafter referred to as "close parts") that are placed in an area where the first magnet (M1) and the second magnet (M2) are close to each other (hereinafter referred to as "close area").

[0103] The above proximity region is a region where the magnetic field from the first magnet (M1) and the magnetic field from the second magnet (M2) can coexist.

[0104] Therefore, the second part (720A) of the first yoke (700A) that generates an attractive force in relation to the first magnet (M1) is positioned in the aforementioned proximity area or is positioned relatively closer to the aforementioned proximity area than the first part (710A), so it can be affected by the second magnet (M2).

[0105] Additionally, the fourth part (710B) of the second yoke (700B), which generates an attractive force in relation to the second magnet (M2), is positioned in the aforementioned proximity area or is positioned relatively closer to the aforementioned proximity area than the third part (720B), so it may be affected by the first magnet (M1).

[0106] Parts placed in the proximity area in this way may be affected by or receive the magnetic field of a magnet other than the intended magnet.

[0107] To rephrase based on the magnets, the first magnet (M1) can be influenced by the fourth part (710B) which generates an attractive force in relation to the second magnet (M2), and the second magnet (M2) can be influenced by the second part (720A) which generates an attractive force in relation to the first magnet (M1).

[0108] In this way, if the first magnet (M1) or / and the second magnet (M2) are affected by a yoke provided in an unintended direction, the driving precision of the OIS may be reduced and may have an adverse effect on functions such as rotation suppression and position restoration.

[0109] In order to effectively resolve this problem, the present invention is configured such that, for example, based on the embodiment illustrated in the drawings, at least one of the second part (720A) of the first yoke (700A) and the fourth part (710B) of the second yoke (700B) placed in the proximity area is smaller in size (length, width, etc.) than other parts. When a part having such a relatively small size is placed in the proximity area, the effect on other adjacent magnets can be reduced.

[0110] Specifically, as illustrated in FIG. 9, the physical specifications (size, length, width, height, etc.) of the second part (720A) and the fourth part (710B) may be configured to be smaller than the physical specifications of the first part (710A) and the third part (720B) (e.g., D2, D4 < D1, D3).

[0111] In this case, for the sake of positional alignment with the magnets (M1, M2) and driving efficiency, it is desirable to configure the second part (720A) and the fourth part (710B) to have the same physical specifications (D2=D4). Correspondingly, it is desirable that the physical specifications (length, height, width, etc.) of the first part (710A) and the third part (720B) be the same (D2=D4). <D1=D3).

[0112] According to an embodiment, as illustrated in FIG. 10, the size of the second part (720A) corresponding to the first yoke (700A) may be configured to be smaller than the size of the first part (710A), the third part (720B), and the fourth part (710B) (D2 <D1, D3, D4).

[0113] In this case, for positional alignment with the magnets (M1, M2) and driving efficiency, it is preferable that the sizes of the first part (710A), the third part (720B), and the fourth part (710B) be the same (D2 <D1=D3=D4).

[0114] According to an embodiment, as illustrated in FIG. 11, the fourth part (710B) included in the second yoke (700B) may be configured to be smaller in size than the first part (710A), the second part (720A), and the third part (720B) (D4 <D1, D2, D3).

[0115] In this case as well, it is preferable that the first to third parts (710A, 710B, 720B) be configured to have the same size as each other (D4 <D1=D2=D3).

[0116] The gap (G1, see FIG. 7) between the first part (710A) and the first magnet (M1) and the gap (G2) between the second part (720A) and the first magnet (M1) may be designed to be identical in that they reduce variable parameters, but depending on the embodiment, they may be configured to have different sizes.

[0117] Although the drawing shows a first yoke (700A) composed of a first part (710A) and a second part (720A), it is obvious that the first yoke may be composed of more parts than those exemplified in the drawing, within the scope of application of this technical concept of making the size of parts located in adjacent areas smaller than the size of other parts.

[0118] For example, if the first yoke (700A) is composed of three parts spaced apart along the length of the first magnet (M1), the first yoke (700A) may include individual parts whose size gradually increases from the position closest to the second magnet (M2) to the position furthest away.

[0119] Additionally, the first yoke (700A) may include a part (adjacent part) positioned closest to the second magnet (M2), which is the smallest part, and two parts having the same size but larger than the adjacent part, which are also the same size. Of course, the details regarding the first yoke (700A) described above may also apply to the second yoke (700B).

[0120] As previously explained with reference to FIG. 6, it may be desirable to configure the size of the third coil (C2B) facing the second magnet (M2) and the size of the fourth coil (C2A) facing the second magnet (M2) differently. FIG. 6 illustrates an embodiment in which the width of the fourth coil (C2A) facing the second magnet (M2) is smaller than the width of the third coil (C2B) facing the second magnet (M2).

[0121] As previously explained, the fourth part (710B) of the second yoke (700B) that generates an attractive force in relation to the second magnet (M2) is a part placed in the proximity area, so it may be smaller in size than other parts, either alone or together with the second part (720A) of the first yoke (700A).

[0122] Therefore, the attractive force between the fourth part (710B) of the second yoke (700B) and the second magnet (M2) may be smaller than the attractive force between the third part (720B) of the second yoke (700B) and the second magnet (M2).

[0123] Therefore, as illustrated in FIG. 6, it is preferable that the fourth coil (C2A), which has a smaller width and faces the second magnet (M2) among the coils of the second coil section (C2), be placed at a position corresponding to the fourth part (710B).

[0124] In the case of an embodiment of the present invention, a coil generating a relatively small driving force can be placed in an area where a relatively small attractive force acts, and a coil generating a relatively large driving force can be placed in an area where a relatively large attractive force acts, thereby organically incorporating the relationship between the magnitude of the force (attractive force) into the OIS drive, so that the OIS drive efficiency can also be improved.

[0125]

[0126] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0127] In the description of the present invention described above, modifiers such as "first," "second," etc., are merely instrumental conceptual terms used to relatively distinguish components from one another, and should be interpreted as not being used to indicate a specific order, priority, etc.

[0128] Although the drawings and other accompanying materials for the description of the present invention and the illustration of embodiments thereof may be depicted in a somewhat exaggerated form to emphasize or highlight the technical content according to the present invention, it should be interpreted as obvious to a person skilled in the art that various modified application examples are possible by considering the aforementioned descriptions and the details illustrated in the drawings.

Claims

1. A first frame moving in a plane direction perpendicular to the optical axis; First and second magnets installed on the first frame to form a right angle; A second frame that supports the movement of the first frame; A first yoke comprising a first part and a second part positioned at a location spaced apart from the first part along the longitudinal direction of the first magnet and closer to the second magnet than the first part, and positioned to face the first magnet; and It includes a third part and a fourth part positioned at a location spaced apart from the third part along the longitudinal direction of the second magnet and closer to the second magnet than the third part, and includes a second yoke positioned to face the second magnet. An actuator for a camera characterized in that one or more of the second and fourth parts are smaller in size than other parts other than themselves.

2. In paragraph 1, the above-mentioned second and fourth parts are, An actuator for a camera characterized by being smaller in size than the first and third parts above.

3. In paragraph 2, the above-mentioned second and fourth parts are, An actuator for a camera characterized by having the same size.

4. In paragraph 2, the above first and third parts are, An actuator for a camera characterized by having the same size.

5. In paragraph 1, the second part is, Smaller in size than the first, third, and fourth parts mentioned above, An actuator for a camera characterized in that the first, third, and fourth parts have the same size as each other.

6. In paragraph 1, the above-mentioned fourth part is, Smaller in size than the first, second, and third parts mentioned above, An actuator for a camera characterized in that the first, second, and third parts have the same size as each other.

7. In Paragraph 1, First and second coils arranged to face the first magnet at different positions and driven independently; and An actuator for a camera characterized by further including third and fourth coils that are positioned to face the second magnet and drive in conjunction.

8. In Paragraph 1, One of the third and fourth coils has a width facing the second magnet smaller than the other, and An actuator for a camera characterized in that among the third and fourth coils, the coil with a smaller width facing the second magnet is positioned at a location corresponding to the fourth part.

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