Actuator for camera

Abstract

An actuator for a camera, according to an embodiment of the present invention, may comprise: a first frame that moves in a plane direction perpendicular to the optical axis; first and second magnets provided on the first frame so as to form a right angle; a second frame that supports movement of the first frame; and first and second yokes formed of magnetic material, provided on the second frame so as to face the first and second magnets, respectively. In this case, at least one of the first and second yokes comprises: a first part disposed to face a first divided region, which is one of two divided regions located at an outer side among k (k is a natural number of 3 or more) divided regions obtained by virtually dividing a target magnet, which is a magnet facing the yoke; and a second part disposed to face a second divided area, which is the other of the two divided areas.

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 one embodiment of the present invention for achieving the above objective may include: a first frame that moves in a planar 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; and first and second yokes made of a magnetic material installed on the second frame to face each of the first and second magnets.

[0015] In this case, one or more of the first and second yoke of the present invention may include: a first part positioned to face a first divided area, which is one of two divided areas located on the outer side of a divided area in which a target magnet, which is a magnet facing itself, is virtually divided into k (k is a natural number greater than or equal to 3) divided areas; and a second part positioned to face a second divided area, which is the other of the two divided areas.

[0016] Specifically, the first part of the present invention may be positioned to face the area including the middle part of the first divided area, and the second part may be positioned to face the area including the middle part of the second divided area.

[0017] Preferably, the divided area of ​​the present invention may be an area divided into three equal sizes.

[0018] In addition, one or more of the first and second parts of the present invention may have a shape that extends in the longitudinal direction of the target magnet, and may be arranged so that the outer end thereof corresponds to the end of the target magnet.

[0019] Furthermore, it is preferable that the first and second parts of the present invention have a shape extended in the longitudinal direction of the target magnet, and are configured to have mutually equal lengths.

[0020] Preferably, the spacing between the first and second parts of the present invention may be greater than the length of the first or second part, and one or more of the first and second parts of the present invention may include a shape in which the outer width is greater than the inner width.

[0021] In addition, the gap between the first part and the target magnet may be the same as the gap between the second part and the target magnet.

[0022] 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.

[0023] 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.

[0024] According to one embodiment of the present invention, by applying a structural arrangement that allows for positional alignment and optimized torque between the yoke and the magnet, 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.

[0025] 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.

[0026] 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.

[0027] FIGS. 1 and 2 are drawings illustrating the overall configuration of a camera actuator according to a preferred embodiment of the present invention.

[0028] FIG. 3 is a drawing illustrating a configuration for driving the movement of the first frame,

[0029] FIG. 4 is a cross-sectional view illustrating the internal structure of a camera actuator according to an embodiment of the present invention.

[0030] FIG. 5 is a diagram illustrating the interrelationship between a coil, a magnet, and a position sensor (Hall sensor).

[0031] FIG. 6 is a drawing illustrating a yoke according to an embodiment of the present invention,

[0032] FIG. 7 is a bottom view illustrating the positional relationship between the magnet and the yoke,

[0033] FIG. 8 is a drawing illustrating a first yoke according to an embodiment of the present invention,

[0034] FIG. 9 is a drawing illustrating an embodiment of a second coil and a second Hall sensor according to the present invention.

[0035] FIGS. 10 to 12 are drawings illustrating a yoke according to another embodiment of the present invention.

[0036] 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.

[0037] 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.

[0038] 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, FIG. 3 is a drawing explaining the configuration for driving the movement of a first frame (200), FIG. 4 is a cross-sectional view illustrating the internal structure of an actuator (1000) according to an embodiment of the present invention, and FIG. 5 is a drawing explaining the interrelationship between a coil, a magnet, and a position sensor (Hall sensor).

[0039] 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 5, etc., and detailed information regarding the yoke of the present invention, which performs the function of suppressing rotation and restoring the position of the first frame (200) that is the moving body of OIS, will be described later.

[0040] 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.

[0041] 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.

[0042] 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).

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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 a case (600) that functions as a shield can may be combined according to an embodiment.

[0047] 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.

[0048] 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).

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] When power of an appropriate size and direction is supplied to the second coil section (C2) through the control of the second drive 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) in the second direction (X-axis direction) relative to the fixed body. Through this movement control, X-axis direction OIS is implemented.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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).

[0058] 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).

[0059] 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).

[0060] 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).

[0061] 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).

[0062] 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.

[0063] 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.

[0064] 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).

[0065] 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.

[0066] 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.

[0067] 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).

[0068] 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).

[0069] 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 (C2A) and the fourth coil (C2B).

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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).

[0074] 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.

[0075] 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).

[0076] 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.

[0077] 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).

[0078] In this way, when the second ball (B2) is provided in one or more of 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).

[0079] 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.

[0080] 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.

[0081] 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.

[0082]

[0083] FIG. 6 is a drawing illustrating a yoke (700A, 700B) according to an embodiment of the present invention, FIG. 7 is a bottom view illustrating the positional relationship between a magnet (M1, M2) and a yoke (700A, 700B), FIG. 8 is a drawing illustrating a first yoke (700A) according to an embodiment of the present invention, and FIG. 9 is a drawing illustrating an embodiment of a second coil (C2) and a second Hall sensor (H2) according to the present invention.

[0084] Hereinafter, with reference to the attached drawings, etc., the specific functions and structures of the yoke (700A, 700B) according to one embodiment of the present invention will be described in detail.

[0085] 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).

[0086] 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 that generates an attractive force with the first magnet (M1). The second yoke (700B), made of a magnetic material, is installed on the second frame (100) to face the second magnet (M2) and generates an attractive force with the second magnet (M2).

[0087] 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).

[0088] 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).

[0089] As illustrated in FIG. 6, etc., 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).

[0090] The first part (710A) and the second part (720A) are magnetic materials installed on the second frame (100) so as to be spaced apart from the first magnet (M1) in the downward direction of the first magnet (M1) (G1, see FIG. 6), and thus can have the function of shielding a portion of the magnetic field of the first magnet (M1).

[0091] Therefore, the magnetic field of the first magnet (M1) recognized by the right first Hall sensor (H1A) (based on FIG. 7) and the left first Hall sensor (H1B) of the first Hall sensor (H1) is affected by the shielding area of ​​the first part (710A) and the second part (720A), respectively.

[0092] Therefore, when physical or structural characteristics such as the size, width, position, and orientation of the first part (710A) and the second part (700B) are different from each other, the shielding area or influence by each of the first and second parts (710A, 720A) will differ from each other, and as a result, the form or characteristics of the magnetic field detected by the right first Hall sensor (H1A) and the left first Hall sensor (H1B) will differ from each other.

[0093] In this way, when the magnetic field characteristics detected by multiple first Hall sensors (H1A, H1B) are different, the precision of the drive control is reduced because the different magnetic field characteristics must be continuously reflected in the drive control. Above all, since these different magnetic field characteristics change randomly and dynamically depending on the position of the first magnet (M1), the precision of rotation detection and rotation correction based on rotation detection may be significantly reduced.

[0094] In addition, if the magnetic field characteristics detected by multiple first Hall sensors (H1A, H1B) are different from each other, the driving precision of the OIS itself may be reduced because the different magnetic field characteristics or environments must be reflected when controlling the magnitude and direction of the current supplied to the first coil (C1A) and the second coil (C1B) for the first direction OIS, that is, for the generation of driving force between the first magnet (M1) and the first coil part (C1).

[0095] To resolve these problems, it is preferable that the first part (710A) and the second part (720A) of the first yoke (700A) be spaced apart along the length direction of the first magnet (M1) and have the same physical characteristics (size, width, length, etc.) (D1=D2, H1=H2, see FIG. 8).

[0096] In this regard, it is preferable that the first part (710A) and the second part (720A) of the first yoke (700A) be arranged symmetrically with respect to the middle portion in the longitudinal direction of the first magnet (M1) (C1=C2, see FIG. 8).

[0097] In addition, if the specifications such as length, width, material, and thickness of the first and second parts (710A, 720A) included in the first yoke (700A) correspond to each other, it is desirable that the gap (G1) between the first part (710A) of the first yoke (700A) and the first magnet (M1) corresponds to the gap (G2) between the second part (720A) of the first yoke (700A) and the first magnet (M1).

[0098] The second yoke (700B) may also be configured to include a first part (710B) and a second part (720B) that are spaced apart along the longitudinal direction of the second magnet (M2) and have the same size (width). Of course, the configuration described above regarding the arrangement, position, structure, etc. of the first yoke (700A) may also be applied to the second yoke (700B).

[0099] 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 (C2A) and the fourth coil (C2B) of the second coil section (C2) are arranged to face the second magnet (M2) at different locations and drive in conjunction.

[0100] 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), wherein 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.

[0101] 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.

[0102] 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).

[0103] 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 (C2A) facing the second magnet (M2) and the size of the fourth coil (C2B) facing the second magnet (M2) differently from each other, as exemplified in FIG. 9.

[0104] 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.

[0105] In this case, the second Hall sensor (H2) facing the second magnet (M2) is preferably positioned in the inner space of the third coil (C2A) as shown in FIG. 9, but is positioned in a location biased in the direction in which the fourth coil (C2B) is positioned.

[0106] 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.

[0107]

[0108] FIGS. 10 to 12 are drawings illustrating a yoke according to another embodiment of the present invention. Hereinafter, specific details of a yoke (700A, 700B) according to another embodiment of the present invention will be described with reference to FIGS. 10 to 12.

[0109] At least one of the first yoke (700A) and the second yoke (700B) may include a first part positioned to face one of two divided regions located on the outer side of a divided region in which the magnet facing it (hereinafter referred to as the 'target magnet') is virtually divided into k parts (hereinafter referred to as the "first divided region"), and a second part positioned to face the other of the two divided regions (hereinafter referred to as the "second divided region"). Here, k, which represents the number of regions in which the facing magnet is virtually divided, is a natural number greater than or equal to 3.

[0110] The first yoke (700A) of the present invention includes a first part (710A) and a second part (720A) arranged to face two division areas located on the outer side among the division areas in which the target magnet (M1), which is a magnet facing itself (the first yoke (700A)), is virtually divided into k division areas.

[0111] Based on the embodiment illustrated in the drawing, the first part (710A) of the first yoke (700A) is positioned to face the first divided area, which is one of the two divided areas located on the outside, and the second part (720A) of the first yoke (700A) is positioned to face the second divided area, which is the other of the two divided areas located on the outside.

[0112] An example is shown in which the first magnet (M1) is divided into three parts. Based on this embodiment, the first part (710A) of the first yoke (700A) is positioned to face the first divided area (Section 1), which is one of the outer divided areas (Section 1, Section 2) among the three divided areas (Section 1, Section 2, Section 3) of the first magnet (M1).

[0113] The second part (720A) of the first yoke (700A) is positioned to face the second section (Section 2), which is the other of the outer section among the three section sections of the first magnet (M1).

[0114] In a corresponding view, the second yoke (700B) is also divided into a first part (710B) and a second part (720B), and the first part (710B) of the second yoke (700B) is positioned to face one of the outer divided areas of the three divided areas of the second magnet (M2) (first divided area, Section 1), and the second part (720B) of the second yoke (700B) is positioned to face another divided area (second divided area, Section 2) of the outer divided areas of the three divided areas of the second magnet (M2).

[0115] In this way, when the first yoke (700A) is divided into a first part (710A) and a second part (720A), and each part (710A, 710B) is positioned to face each of the outer regions of the first magnet (M1) which is divided into three or more parts, the attractive force (first magnet vs. first yoke) can be induced to be concentrated in the outer region based on the center part of the first magnet (M1), thereby more effectively suppressing the rotation of the first frame (200) equipped with the first magnet (M1) and more effectively inducing the restoration of the first frame (200) to its correct position.

[0116] It is preferable that the first part (710A) of the first yoke (700A) be positioned to face the area containing the middle part (CR1) of the first divided area (Section 1), and the second part (720A) of the second yoke (700B) be positioned to face the area containing the middle part (CR2) of the second divided area (Section 2).

[0117] In the case of the embodiment of the present invention, the position where the torque is applied, the magnitude of the torque at each position, as well as the position alignment with the first magnet (M1) and the weight balance of the first magnet (M1) can be reflected, thereby enabling more stable implementation of rotation suppression and position restoration of the first frame (200).

[0118] In this regard, as illustrated in the drawing, it is preferable that the virtual division areas (Sections 1 to 3) in the first magnet (M1) be divided into areas of equal size (W1=W2=W3).

[0119] In addition, the first part (710A) of the first yoke (700A) and the second part (720A) of the first yoke (700A) are preferably configured to have a shape that extends in the longitudinal direction of the target magnet (first magnet (M1)) and have mutually equal lengths (D1=D2, see FIG. 10 and FIG. 11).

[0120] It is preferable that the first part (710A) of the first yoke (700A) and the second part (720A) of the first yoke (700A) be arranged symmetrically, and that the divided area of ​​the first magnet (M1) be divided into three or more areas so that the attractive force exerted by the first yoke (700A) acts relatively strongly on the outer side of the first magnet (M1).

[0121] In order for an appropriate amount of attractive force to be generated between the first and second parts (710A, 720A) of the first yoke (700A) and the first magnet (M1), it may be preferable to have three virtual division areas in the first magnet (M1).

[0122] As exemplified in FIG. 11 (a), the first part (710A) of the first yoke (700A) is positioned to face the first magnet (M1) with the first divided area (Section 1) as the center, and if positioned to be spaced apart from the second part (720A) of the first yoke (700A), it may also be positioned to face a part of the middle divided area (Section 3) of the first magnet (M1).

[0123] However, as illustrated in FIG. 11 (b), so that the force exerted by the first yoke (700A) can be concentrated more on the outer side of the first magnet (M1), it is preferable that the distance (GD) between the first part (710A) of the first yoke (700A) and the second part (720A) of the second yoke (700B) be greater than the length (D1) of the first part (710A) of the first yoke (700A) or the length (D2) of the second part (720A) of the first yoke (700A).

[0124] In order to reduce space, lighten weight, and eliminate redundant functions, it is preferable that the first part (710A) or the second part (720A) of the first yoke (700A) be positioned so that its outer end does not extend beyond the outer end of the first magnet (M1), as illustrated in FIG. 11.

[0125] It is preferable that at least one of the first part (710A) of the first yoke (700A) and the second part (720A) of the first yoke (700A) be configured to include a shape in which the outer width is larger than the inner width, as illustrated in FIG. 12 (a) and (b).

[0126] In the case of such an embodiment of the present invention, the attractive force acting on the inner and outer sides of the first yoke (700A) can be differentiated, thereby more effectively suppressing the rotation of the first frame (200) equipped with the first magnet (M1) and more quickly restoring the rotated first frame (200) to its original position.

[0127] Of course, the configuration, structure, arrangement, etc. of the first part (710A) and the second part (720A) of the first yoke (700A) described above can also be applied to the first part (710B) and the second part (720B) of the second yoke (700B).

[0128]

[0129] 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.

[0130] 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.

[0131] 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 applications 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 supporting the movement of the first frame; and It includes first and second yokes made of magnetic material installed on the second frame to face each of the first and second magnets, and One or more of the above first and second yoke are, A first part positioned to face a first divided area, which is one of two divided areas located on the outer side among the divided areas in which the target magnet, which is the magnet it faces, is virtually divided into k (k is a natural number greater than or equal to 3); and An actuator for a camera characterized by including a second part positioned to face a second divided area, which is the other of the two divided areas mentioned above.

2. In paragraph 1, the above-mentioned first part is, It is positioned to face the area that includes the middle part of the first divided area, and An actuator for a camera characterized in that the second part is positioned to face the area containing the middle part of the second divided area.

3. In paragraph 1, the above-mentioned divided area is, An actuator for a camera characterized by having areas divided into three equal sizes.

4. In paragraph 1, one or more of the first and second parts are, An actuator for a camera characterized by having a shape extended in the longitudinal direction of the above-mentioned target magnet, wherein the outer end thereof is positioned to correspond to the end of the above-mentioned target magnet.

5. In paragraph 1, the above first and second parts are, An actuator for a camera characterized by having a shape extended in the longitudinal direction of the above-mentioned target magnet, while having mutually identical lengths.

6. In Paragraph 5, An actuator for a camera characterized in that the distance between the first and second parts is greater than the length of the first or second part.

7. In paragraph 1, one or more of the first and second parts are, An actuator for a camera characterized by including a shape in which the outer width is larger than the inner width.

8. In Paragraph 1, An actuator for a camera characterized in that the gap between the first part and the target magnet is the same as the gap between the second part and the target magnet.

9. 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.

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