Camera actuator

Abstract

A camera actuator is disclosed. The camera actuator includes an OIS carrier, a base, a first driver, a second driver, at least one first sensor for sensing a distance from a first magnet, and at least one second sensor for sensing a magnetic field change in the boundaries of the magnetic poles of the first magnet.

Description

Camera actuator

[0001] The present invention relates to a camera actuator, and more specifically, to a camera actuator configured to enhance OIS driving characteristics even within a limited space.

[0002] A conventional camera actuator discloses a structure in which an AF carrier and an OIS carrier are accommodated in an internal receiving space of a housing (fixed body) and stacked together in the direction of the optical axis, and includes a middle guide that supports the OIS carrier while receiving physical support from a ball interposed as needed, and a sensing sensor that detects the movement of the AF carrier or the OIS carrier.

[0003] Meanwhile, current mobile devices (smartphones) are seeking developments to increase lens size and achieve device miniaturization or slimming.

[0004] Accordingly, the camera actuator needed to optimize the placement of components within a limited space while maximizing the driving force of the actuator to implement AF (Auto Focus) or OIS (Optical Image Stabilizer) functions.

[0005] In other words, a problem arises in that the driving force must be maximized by optimizing the amount of coil windings and the size of the magnet constituting the drive unit within a limited space.

[0006] Meanwhile, in the case of camera actuators that include a middle guide, the axial weight often varies depending on the shape and placement of the middle guide.

[0007] Accordingly, to implement the OIS function, there was inevitably a difference between the driving force required for movement in the X-axis direction (first direction) and the driving force required for movement in the Y-axis direction (second direction); therefore, development efforts are being made to seek miniaturization or slimming of the device by reducing the coil size in the direction requiring less driving force and increasing the coil size in the direction requiring more driving force.

[0008] However, since detection sensors are placed in the X-axis direction (first direction) and Y-axis direction (second direction) of the OIS carrier, respectively, there was a limit to increasing or decreasing the amount of coil winding due to the physical size of the detection sensors.

[0009] Meanwhile, in the case of a camera actuator that does not include a middle guide, since there is no middle guide to induce linear movement in a direction perpendicular to the optical axis while controlling the rotation of the OIS carrier, it was necessary to accurately detect and correct the first direction movement, second direction movement, or rotational movement of the OIS carrier.

[0010] To this end, a structure has been disclosed in which the coil is separated into two on one side of the first or second direction of the OIS carrier and a driving driver is provided to control each of them to increase driving precision.

[0011] However, just like a camera actuator including a middle guide, since sensing sensors are arranged in the X-axis direction (first direction) and the Y-axis direction (second direction) respectively, there was a similar limitation in optimizing the size of the drive unit by increasing or decreasing the winding amount of the coil in one direction depending on the physical size of the sensing sensors.

[0012] Furthermore, camera actuators that do not include a middle guide could experience a problem where driving precision is reduced if errors occur in the assembly arrangement of the drive unit due to assembly tolerances of the camera actuator, leading to incorrect reception of sensing values ​​from the detection sensor.

[0013] For example, referring to FIG. 1(a), a conventional camera actuator is configured with a first magnet (M1) on the side of the OIS carrier (10) in the first direction (X-axis direction) to generate driving force for the OIS carrier (10), and a first drive unit is configured by placing at least one first coil (C1) facing the first magnet (M1). Additionally, a first sensor (H1) is configured to sense the distance (d1) between the first magnet (M1) and the first coil (C1) to detect movement of the OIS carrier (10).

[0014] Additionally, a second magnet (M2) is configured on the second direction (Y-axis direction) side of the OIS carrier (10), and at least one second coil (C2) is arranged facing the second magnet (M2) to form a second driving unit, and a second sensor (H2) is configured to sense the distance (d2) between the second magnet (M2) and the second coil (C2).

[0015] At this time, although the description was exaggerated for ease of explanation, there may be cases where the second magnet (M2) is assembled with an inclination that is not aligned with the Y-axis plane of the actual OIS carrier (10) due to assembly tolerances. In reality, such assembly tolerances inevitably occur during the assembly process.

[0016] Figure 1(b) shows the case where the OIS carrier (10) moves by an interval of r1 in the first direction (X-axis direction).

[0017] At this time, the first sensor (H1) can detect that the first magnet (M1) moves from the interval of d1 to the interval of d1' and moves in the first direction by r1, and can calculate an accurate sensing value for feedback control.

[0018] At this time, the second sensor (H2) must continue to sense the spacing between the second magnets (M2) as d2 because the actual OIS carrier (10) has not moved in the second direction (Y-axis direction).

[0019] However, as in the city, even though the OIS carrier (10) has moved by r1 only in the first direction, due to assembly tolerance, the second sensor (H2) detects an error that the second magnet (M2) has moved in the second direction. That is, the second sensor (H2) detects an error that the second magnet (M2) has moved from d2 to d2' by the difference value (e) in the second direction, thereby confirming that the OIS carrier (10) has moved in the second direction.

[0020] In this regard, the driving driver is forced to command feedback control of the OIS carrier (10) not only in the first direction but also in the second direction that did not actually occur, and this inevitably lowers the driving precision of the OIS.

[0021] The present invention aims to solve the aforementioned problems by providing a camera actuator that enhances OIS driving characteristics by maximizing driving force even within a limited space, thereby enabling miniaturization and slimness while satisfying user needs.

[0022] In addition, the purpose is to provide a camera actuator that can increase the driving precision of OIS by accurately sensing posture defects such as rotation and tilt of the OIS carrier, which moves finely while generating maximum driving force within a limited space.

[0023] In addition, the purpose is to provide a camera actuator that can increase OIS driving precision despite the occurrence of assembly errors in the camera actuator by equipping a sensor to sense only one of the directions perpendicular to the optical axis.

[0024] The problems of the present invention are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art to which the present invention pertains from the description below.

[0025] According to one aspect of the present invention, a camera actuator is provided.

[0026] A camera actuator may include: an OIS carrier that moves in a first direction or a second direction perpendicular to the optical axis direction; a base that accommodates the OIS carrier; a first driving unit comprising a first magnet provided on the first direction side of the OIS carrier and a first coil disposed facing the first magnet; a second driving unit comprising a second magnet provided on the second direction side of the OIS carrier and a second coil disposed facing the second magnet; at least one first sensor disposed facing the first magnet and sensing the distance between the first coil and the first magnet; and at least one second sensor disposed at the magnetic field boundary of the first magnet and sensing a change in the magnetic field due to a change in the magnetic field boundary position of the first magnet.

[0027] At this time, the first sensor can sense the amount of displacement of the OIS carrier in the first direction according to the change in the distance interval between the first magnets, and the second sensor can sense the amount of displacement of the OIS carrier in the second direction according to the change in the magnetic field caused by the change in the position of the magnetic pole boundary of the first magnet.

[0028] At this time, the first sensor may be positioned at the center side of the winding of the first coil, and the second sensor may be positioned at the boundary side of the winding of the first coil.

[0029] At this time, the first coil comprises a first-1 coil and a first-2 coil arranged adjacent to the first-1 coil in a second direction; and the first magnet may comprise a first-1 magnet facing the first-1 coil and a first-2 magnet facing the first-2 coil.

[0030] At this time, the first sensor may include a first-1 sensor disposed on the center side of the winding of the first-1 coil and a first-2 sensor disposed on the center side of the winding of the first-2 coil.

[0031] At this time, the second sensor is positioned at the boundary of the magnetic poles of the first-1 magnet or the first-2 magnet between the first-1 coil and the first-2 coil, and can sense changes in the magnetic field resulting from changes in the position of the magnetic pole boundary of the first-1 magnet or the first-2 magnet.

[0032] At this time, the second sensor is positioned at the boundary of the magnetic pole of the first-1 magnet on the winding boundary side of the first-1 coil, and can sense changes in the magnetic field due to changes in the position of the magnetic pole boundary of the first-1 magnet.

[0033] At this time, the second sensor is positioned at the boundary of the magnetic pole of the first-2 magnet on the winding boundary side of the first-2 coil, and can sense changes in the magnetic field due to changes in the position of the magnetic pole boundary of the first-2 magnet.

[0034] At this time, the camera actuator may include: an AF carrier that is accommodated in the base portion and moves in the direction of the optical axis including the OIS carrier; and an AF driving portion including an AF coil provided in the base and an AF magnet provided in the AF carrier facing the AF coil.

[0035] At this time, the camera actuator may further include a middle guide interposed between the AF carrier and the OIS carrier and supporting the movement of the OIS carrier.

[0036] At this time, the first sensor and the second sensor may be composed of Hall sensors.

[0037] According to the above configuration, the camera actuator according to the present invention has the effect of increasing the driving force by increasing the winding amount of the coil in the other direction in which a large driving force is required, by arranging the first sensor and the second sensor to sense only the magnet of the driving unit placed in one direction perpendicular to the optical axis direction in which a large driving force is not required.

[0038] In addition, it has the effect of increasing the driving precision of OIS by accurately sensing posture defects such as rotation and tilt of the OIS carrier, which moves finely while generating maximum driving force within a limited space.

[0039] In addition, by equipping the sensor to sense only the magnet in either the optical axis direction or the direction perpendicular to it, it has the effect of increasing the OIS driving precision despite the occurrence of assembly errors.

[0040] In addition, the first sensor is positioned to sense the movement distance of the first magnet, and the second sensor is positioned to sense the change in magnetic quantity of the first magnet, so that even if the first sensor and the second sensor are positioned in the same direction, the movement of the OIS carrier in the first direction and the second direction can be accurately sensed.

[0041] In addition, by reducing the coil size in the direction requiring less driving force and increasing the coil size in the direction requiring more driving force, it is possible to achieve miniaturization or slimming of the device, while simultaneously maximizing driving force even within a limited space to enhance OIS driving characteristics.

[0042] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

[0043] Figures 1(a) and 1(b) are schematic diagrams illustrating the OIS driving characteristics of a camera actuator according to the prior art.

[0044] FIG. 2 is a drawing showing a camera actuator according to one embodiment of the present invention.

[0045] FIG. 3 is a drawing showing an example of a structure including a middle guide in a camera actuator according to an embodiment of the present invention.

[0046] FIG. 4 is a drawing showing an example of a structure that does not include a middle guide in a camera actuator according to an embodiment of the present invention.

[0047] FIG. 5 is a schematic diagram showing an example of a first driving unit and a second driving unit applied to a camera actuator according to an embodiment of the present invention.

[0048] FIGS. 6 and FIGS. 7 are schematic diagrams showing various arrangement examples of a second sensor in a camera actuator according to one embodiment of the present invention.

[0049] FIG. 8 is a schematic diagram illustrating sensing according to the movement of an OIS carrier in a first direction in a camera actuator according to one embodiment of the present invention.

[0050] FIG. 9 is a schematic diagram illustrating sensing according to the movement of an OIS carrier in a second direction in a camera actuator according to an embodiment of the present invention.

[0051] FIG. 10 is a schematic diagram illustrating sensing according to the rotational movement of an OIS carrier in a camera actuator according to one embodiment of the present invention.

[0052] The present invention provides a camera actuator comprising, in its best form, an OIS carrier that moves in a first direction or a second direction perpendicular to the optical axis direction; a base that accommodates the OIS carrier; a first driving unit comprising a first magnet provided on the first direction side of the OIS carrier and a first coil disposed facing the first magnet; a second driving unit comprising a second magnet provided on the second direction side of the OIS carrier and a second coil disposed facing the second magnet; at least one first sensor disposed facing the first magnet and sensing the distance between the first coil and the first magnet; and at least one second sensor disposed at the magnetic field boundary of the first magnet and sensing a change in the magnetic field due to a change in the magnetic field boundary position of the first magnet.

[0053] Hereinafter, embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein. To clearly explain the present invention, parts unrelated to the description in the drawings have been omitted, and the same reference numerals have been used throughout the specification for identical or similar components.

[0054] The words and terms used in this specification and claims are not limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention in accordance with the principles by which the inventor defines terms and concepts to best describe his invention.

[0055] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings correspond to preferred embodiments of the present invention and do not represent all technical ideas of the present invention; thus, various equivalents and modifications that may replace such configurations may exist at the time of filing the present invention.

[0056] In this specification, terms such as “comprising” or “having” are intended to describe the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should not be understood as precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0057] The statement that a component is "in front," "rear," "upper," or "lower" of another component includes, unless there are special circumstances, not only being positioned "in front," "rear," "upper," or "lower" in direct contact with the other component, but also cases where another component is positioned in between. Furthermore, the statement that a component is "connected" to another component includes, unless there are special circumstances, not only being directly connected to each other, but also being indirectly connected to each other.

[0058] The terms "X-axis," "Y-axis," and "Z-axis" used in the description will be understood by referring to the coordinate system depicted in the drawing. Also, in the description, the X-axis direction is referred to as the first direction, the Y-axis direction as the second direction, and the Z-axis direction as the third direction, but this is merely an example based on a relative perspective. The first to third directions and the coordinate axes (X, Y, Z axes) are introduced only to describe the relative positions between the components and do not limit the absolute positions of each component.

[0059] In addition, the "optical axis direction" used in the following description refers to the direction in which light enters, which is identical to the "Z-axis direction," or the third direction, and will be understood by referring to the illustrated coordinate system.

[0060] Furthermore, in describing the present invention, specific descriptions of related known functions or configurations are omitted to avoid obscuring the gist of the invention.

[0061]

[0062] Hereinafter, a camera actuator according to one embodiment of the present invention will be described with reference to the drawings.

[0063] FIG. 2 is a drawing showing a camera actuator according to an embodiment of the present invention, FIG. 3 is a drawing showing an example of a structure including a middle guide in a camera actuator according to an embodiment of the present invention, and FIG. 4 is a drawing showing an example of a structure not including a middle guide in a camera actuator according to an embodiment of the present invention. FIG. 5 is a schematic drawing showing an example of a first driving unit and a second driving unit applied to a camera actuator according to an embodiment of the present invention, and FIG. 6 and FIG. 7 are schematic drawings showing various arrangement examples of a second sensor in a camera actuator according to an embodiment of the present invention. And, FIG. 8 is a schematic diagram for explaining sensing according to movement of an OIS carrier in a first direction in a camera actuator according to an embodiment of the present invention, FIG. 9 is a schematic diagram for explaining sensing according to movement of an OIS carrier in a second direction in a camera actuator according to an embodiment of the present invention, and FIG. 10 is a schematic diagram for explaining sensing according to rotational movement of an OIS carrier in a camera actuator according to an embodiment of the present invention.

[0064] As described above, a camera actuator (1) according to one embodiment of the present invention is supported and mounted on a substrate (not shown) of a mobile terminal (hereinafter referred to as an "electronic device"), such as a mobile phone or smartphone, as well as an independent camera device.

[0065] For example, in FIG. 2, a camera actuator (1) according to one embodiment of the present invention may include a housing (A) comprising a base (200) and a shield can (600), and a carrier (CA) and a lens module (R) for implementing AF and / or OIS functions.

[0066] In addition to the configuration for implementing AF (Auto Focus) and OIS (Optical Image Stabilizer) functions, the camera actuator (1) according to one embodiment of the present invention may also include a lens module (R) and an iris module (not shown) that controls the amount of light (light intensity) to the lens module.

[0067] Meanwhile, through FIGS. 3 and 4, the camera actuator (1) according to one embodiment of the present invention is illustrated as an embodiment in which AF and OIS functions are integrated together, but this is only one embodiment, and it is obvious that the camera actuator (1) of the present invention can be implemented as an actuator for only the OIS function depending on the embodiment. In addition, the camera actuator (1) of the present invention may be implemented in the form of a camera module including one or more lenses and image sensors such as CCD, CMOS, etc.

[0068] Referring again to FIGS. 2 to 4, a camera actuator (1) according to one embodiment of the present invention comprises a housing (A) largely composed of a base (200) and a shield can (600), and a carrier (CA) including an AF carrier (300) and an OIS carrier (100).

[0069] At this time, the carrier (CA) may include a middle guide (400) that supports stable linear movement of the OIS carrier (100) through an interposed ball (B) as in FIG. 3, or may have a structure that does not include a middle guide as in FIG. 4.

[0070] In one embodiment of the present invention, a camera actuator (1) is arranged such that an OIS carrier (100) that implements an OIS function while moving in a first direction or a second direction perpendicular to the optical axis direction is accommodated in an internal receiving space of a base (200).

[0071] The movement of the OIS carrier (100) in the first direction is performed by the driving force generated by a first driving unit composed of a first magnet (M1) and a first coil (C1), and the movement of the OIS carrier (100) in the second direction is performed by the driving force generated by a second driving unit composed of a second magnet (M2) and a second coil (C2).

[0072] And, the movement of the OIS carrier (100) in the first direction or the second direction can be sensed through the first sensor (H1) and the second sensor (H2) and feedback controlled.

[0073] Meanwhile, the camera actuator (1) according to one embodiment of the present invention is configured to achieve miniaturization and slimness desired by the user, and to maximize the driving force even within a limited space, thereby enhancing OIS driving characteristics.

[0074] To this end, a camera actuator (1) according to one embodiment of the present invention can increase the driving force by increasing the winding amount of the coil in the other direction in which a large driving force is required, by arranging a first sensor (H1) and a second sensor (H2) in one direction to sense only the magnet of the driving unit arranged in one direction, which is perpendicular to the optical axis direction and a second direction in which a large driving force is not required.

[0075] Through this, the camera actuator (1) according to one embodiment of the present invention can achieve maximum driving force even within a limited space, thereby suppressing rotational movement of the OIS carrier (100) and increasing OIS driving precision.

[0076]

[0077] Referring again to FIGS. 2 to 5, the camera actuator (1) of the present invention is described as follows.

[0078] First, the housing (A) can be composed of a combination of a base (200) and a shield can (600).

[0079] The base (200) has a structure in which a carrier (CA) that moves in the direction of the optical axis (third direction) or in a direction perpendicular to the optical axis (first direction or second direction) is accommodated inside, and the lower part is supported on a substrate on which a camera actuator (1) is mounted.

[0080] The base (200) includes coils (C1, C2, AF / C) for AF or OIS driving and a flexible printed circuit board (FPCB) (not shown) electrically connected to apply power to the coils (C1, C2, AF / C). This FPCB is electrically connected to a substrate on which the camera actuator (1) is mounted.

[0081] In addition, although not shown, an image sensor (not shown), such as a CCD (Charged-coupled Device) or CMOS (Complementary Metal-oxide Semiconductor), may be provided at the bottom of the base (200) in the direction of the optical axis.

[0082] The FPCB includes a control circuit (drive driver) related to the driving of the camera actuator (1), and can supply a designated signal (e.g., power supply through the supply of a designated amount of current) to the coils (C1, C2, AF / C) for driving, and generates a control signal for driving. Since such an FPCB is already known, a specific description of the related known functions or configurations is omitted to avoid obscuring the gist of the present invention.

[0083] Meanwhile, the shield can (600) has a structure that covers the base (200) and is coupled to the upper part of the base (200).

[0084] Such shield cans (600) can serve to protect or secure related components, including a carrier (CA) accommodated in a base (200). For this purpose, the shield cans (600) may be made of a metal material or a material having a hardness greater than a specified size (e.g., metal or reinforced plastic).

[0085] In addition, the lens module (R) is housed within the housing (A) so as to be driven together with the carrier (CA), and movement can be performed together with the optical axis or in a direction perpendicular to the optical axis depending on the function implementation of the carrier (CA). The amount of light (light intensity) of this lens module (R) can be adjusted according to the driving of the iris module (not shown).

[0086] Meanwhile, the carrier (CA) may include an AF carrier (300) for implementing an AF function and an OIS carrier (100) for implementing an OIS function. In this case, according to an embodiment, as shown in FIG. 3, it may have a structure that further includes a middle guide (400) interposed between the AF carrier (300) and the OIS carrier (100) and supporting the movement of the OIS carrier (100).

[0087] The AF carrier (300) is accommodated in the internal receiving space of the base (200), and in the embodiment of FIG. 3, it includes an OIS carrier (100) and a middle guide (400), and in the embodiment of FIG. 4, it includes only the OIS carrier (100), so that it can move in the optical axis direction as a moving body with the base (200) as a relative fixed body.

[0088] Movement of the AF carrier (300) in the direction of the optical axis can be performed by a driving force generated by an AF driving unit comprising an AF coil (AF / C) provided in the base (200) and an AF magnet (AF / M) provided in the AF carrier (300) facing the AF coil (AF / C).

[0089] In the embodiments of FIGS. 3 and 4, the AF coil (AF / C) and AF magnet (AF / M) constituting the AF drive unit are shown as being composed of a single coil and magnet, but they are not limited thereto and can be composed of a plurality of coils and a plurality of corresponding magnets.

[0090] Meanwhile, the OIS carrier (100) is accommodated in the internal receiving space of the base (200), and in the embodiment of FIG. 3, it moves as a moving body in a first direction or a second direction perpendicular to the optical axis direction with the middle guide (400) and / or AF carrier (300) as a relative fixed body, and in the embodiment of FIG. 4, it can move as a moving body in a first direction or a second direction perpendicular to the optical axis direction with the AF carrier (300) as a relative fixed body.

[0091] Movement of the OIS carrier (100) in a direction perpendicular to the optical axis direction, i.e., in a first direction or a second direction, can be performed by a first driving unit including a first coil (C1) and a first magnet (M1), and a second driving unit including a second coil (C2) and a second magnet (M2).

[0092] For example, referring to FIGS. 3 and FIGS. 4, the first magnet (M1) of the first driving unit may be provided on the first directional side of the OIS carrier (100), and the first coil (C1) may be provided on the first directional side of the base (200) facing the first magnet (M1).

[0093] Additionally, the second magnet (M2) of the first driving unit may be provided on the second directional side of the OIS carrier (100), and the second coil (C2) may be provided on the second directional side of the base (200) facing the second magnet (M2).

[0094] According to this configuration, the OIS carrier (100) can be controlled to move in a first direction (X-axis direction) by a driving force generated by a first driving unit (see FIG. 8), and can be controlled to move in a second direction (Y-axis direction) by a driving force generated by a second driving unit (see FIG. 9).

[0095] Meanwhile, referring to FIGS. 3 and 4, the first coil (C1) and the second coil (C2) may be configured as at least one according to the embodiment. In other words, the first coil (C1) and the second coil (C2) are not limited to the number shown in the illustrated embodiment, and may be configured as a plurality of coils according to the embodiment. Furthermore, the first magnet (M1) and the second magnet (M2) facing them may also be configured as at least one according to the embodiment, or as a plurality if necessary.

[0096] The driving for implementing the functions of the AF carrier (300), middle guide (400), and OIS carrier (100) involves interposing a ball (B) between a moving body and a stationary body (a configuration fixed relative to the moving body) to continuously maintain an appropriate separation distance between the moving body and the stationary body, and to enable accurate movement through the rotational movement of the ball and point contact with the ball with minimized frictional force.

[0097] Since the functional implementation of the AF carrier (300) and OIS carrier (100) by a driving unit composed of magnets (M1, M2, AF / M) facing the coils (C1, C2, AF / C) can be achieved using known techniques, a detailed description of the related configuration is omitted to avoid obscuring the gist of the invention.

[0098] However, the camera actuator (1) according to one embodiment of the present invention has a structure that can detect the position of the carrier (CA) and the like according to the implementation of the AF function of the AF carrier (300) and the OIS function of the OIS carrier (100), and transmit a corresponding signal to the driving driver of the FPCB so that power of a corresponding size and direction is applied to the coil (C1, C2, AF / C).

[0099] To this end, detection sensors (AF / H, H1, H2) that detect the position, direction, etc. of the carrier (CA) may be further included.

[0100] These sensing sensors (AF / H, H1, H2) may be Hall sensors that utilize the Hall effect to detect changes in the magnitude and direction of the magnetic field of a magnet (AF / M, M1, M2) present within the sensing area and output an electrical signal accordingly.

[0101] The position and direction of the AF carrier (300) can be sensed through the AF sensor (AF / H), and the position and direction of the OIS carrier (100) can be sensed through the first sensor (H1) and the second sensor (H2).

[0102] Referring to FIGS. 3 and 4, the AF sensor (AF / H) can be positioned on the center side of the winding of the AF coil (AF / C), and detects the position of the AF magnet (AF / M) facing the AF coil (AF / C) in the direction of the optical axis, and power of a corresponding size and direction is applied to the AF coil (AF / C). Of course, the AF sensor (AF / H) can be configured in multiple units corresponding to the number of AF coils (AF / C), and can also have a structure arranged in the direction of the optical axis as needed.

[0103] And, the first sensor (H1) can be positioned on the center side of the winding of the first coil (C1), and detects the position of the first magnet (M1) facing the first coil (C1) in the first direction, and power of a corresponding size and direction is applied to the first coil (C1).

[0104] Meanwhile, the second sensor (H2) is positioned in the same direction as the first sensor (H1), specifically, it may be positioned on the outer edge of the first coil (C1) to sense changes in the magnetic field resulting from changes in the magnetic field boundary position of the first magnet (M1) facing the first coil (C1). The second sensor (H2) detects the position of the first magnet (M1) in the second direction, etc., and causes power of a corresponding magnitude and direction to be applied to the second coil (C2).

[0105] A camera actuator (1) according to one embodiment of the present invention aims to maximize the driving force within a limited space to enable miniaturization and slimming of the device, thereby enhancing OIS driving characteristics, and to increase the driving precision of OIS through accurate sensing of posture defects such as rotation and tilt of the OIS carrier that moves finely.

[0106] To this end, a camera actuator (1) according to one embodiment of the present invention has a first sensor (H1) and a second sensor (H2) positioned on the first direction side to detect movement in a first direction or a second direction perpendicular to the optical axis of the OIS carrier (100), and is positioned to detect a change in the first magnet (M1) in the same way.

[0107] Accordingly, the second coil (C2) positioned in the second direction perpendicular to the optical axis direction can secure additional physical space equal to the size of the sensor, and accordingly, the amount of winding of the second coil (C2) can be increased to increase the driving force.

[0108] In addition, the first sensor (H1) is positioned to sense the movement distance of the first magnet (M1), and the second sensor (H2) is positioned to sense the change in magnetic quantity at the magnetic boundary position of the first magnet (M1). This allows the movement of the OIS carrier (100) to be accurately sensed even if the first sensor (H1) and the second sensor (H2) are positioned in the same direction, thereby increasing the driving precision of the OIS along with the increased driving force.

[0109] Meanwhile, although it has been described that in one embodiment, the first sensor (H1) and the second sensor (H2) are positioned on the first direction side, it is obvious that the first sensor (H1) and the second sensor (H2) may also be positioned on the second direction side depending on the embodiment of the camera actuator (1).

[0110] At this time, the first sensor (H1) and the second sensor (H2) can be configured in the form of Hall sensors.

[0111]

[0112] Referring again to FIGS. 5 to 10, the arrangement of the driving part and the sensing sensor of a camera actuator (1) according to one embodiment of the present invention and the OIS driving characteristics through it are as follows.

[0113] As described, the camera actuator (1) of the present invention may include an OIS carrier (100).

[0114] The OIS carrier (100) can move in a first direction or a second direction perpendicular to the optical axis direction (see FIG. 8 and FIG. 9). Additionally, depending on the structural features of the embodiment, the OIS carrier (100) may move in a poor posture such as rotation or tilt (see FIG. 10).

[0115] Accordingly, the camera actuator (1) of the present invention is configured to maximize driving force within a limited space while achieving miniaturization and slimness, and to accurately sense posture defects such as rotation and tilt of the OIS carrier that moves finely, thereby increasing the driving precision of the OIS.

[0116] To this end, referring to FIG. 5, a camera actuator (1) according to one embodiment of the present invention is provided with a first driving unit comprising a first magnet (M1) provided on a first directional side of an OIS carrier (100) and a first coil (C1) disposed facing the first magnet (M1).

[0117] And, a second driving unit is provided, comprising a second magnet (M2) provided on the second directional side of the OIS carrier (100) and a second coil (C2) positioned facing the second magnet (M2).

[0118] And, at least one first sensor (H1) is positioned facing the first magnet (M1) and senses the distance interval (a1, a2, a1', a2') between the first coil (C1) and the first magnet (N1).

[0119] And, at least one second sensor (H2) is placed at the magnetic boundary (O1, O2, O1', O2', O1"-1, O1"-2; see FIG. 6 and FIG. 7) of the first magnet (M1), and senses the change in the magnetic field due to the change in the position of the magnetic boundary of the first magnet.

[0120] It is desirable that these first sensor (H1) and second sensor (H2) be positioned in a location that can increase sensing efficiency while minimizing the physical space occupied. Accordingly, the first sensor (H1) can preferably be positioned at the center axis of the winding of the first coil (C1). And, the second sensor (H2) can preferably be positioned at the boundary side of the winding of the first coil (C1).

[0121] Meanwhile, it goes without saying that the first drive unit and the second drive unit can be composed of multiple coils and magnets as needed.

[0122] For example, according to an embodiment, as shown in FIG. 5, the first coil (C1) may include a first-1 coil (C1-1) and a first-2 coil (C1-2) arranged adjacent to the first-1 coil (C1-1) in a second direction.

[0123] At this time, the first magnet (M1) facing the first coil (C1) may include a first-1 magnet (M1-1) facing the first-1 coil (C1-1) and a first-2 magnet (M1-2) facing the first-2 coil (C1-2).

[0124] Accordingly, the first sensor (H1) may include a first-1 sensor (H1-1) positioned at the center of the winding of the first-1 coil (C1-1) and a first-2 sensor (H1-2) positioned at the center of the winding of the first-2 coil (C1-2).

[0125] The first-1 sensor (H1-1) and the first-2 sensor (H1-2) can each sense the distance interval (a1, a2, a1', a2') between the first-1 magnet (M1-1) and the first-2 magnet (M1-2) placed in the same direction and moved in the first direction according to the movement of the OIS carrier (100) (see FIG. 8).

[0126] At this time, the 1-1 magnet (M1-1) and the 1-2 magnet (M1-2) can be arranged with different polarities.

[0127] Additionally, the second coil (C2) may include a second-1 coil (C2-1) and a second-2 coil (C2-2) arranged adjacent to the second-1 coil (C2-1) in a first direction.

[0128] At this time, the second magnet (M2) facing the second coil (C2) may include a second-1 magnet (M2-1) facing the second-1 coil (C2-1) and a second-2 magnet (M1-2) facing the second-2 coil (C2-2).

[0129] Meanwhile, the second sensor (H2) is positioned between the first-1 coil (C1-1) and the first-2 coil (C1-2) described above and can sense changes in the magnetic field due to changes in the position of the magnetic pole boundary (O1, O2) of the first-1 magnet (M1-1) or the first-2 magnet (M1-2).

[0130] In this way, the first sensor (H1) can sense the amount of movement variation of the OIS carrier (100) in the first direction according to the change in the distance interval between the first magnets (M1).

[0131] And, the second sensor (H2) can sense the amount of movement variation of the OIS carrier (100) in the second direction according to the change in the magnetic field caused by the change in the position of the stimulation boundary of the first magnet (M1).

[0132] Referring to FIG. 6, as described above, the second sensor (H2) is positioned at the boundary of the magnetic pole of the first magnet (M1; M1-1, M1-2) constituting the first driving unit on the first direction side, and senses the change in the magnetic field due to the change in the position of the magnetic pole boundary of the first magnet (M1; M1-1, M1-2).

[0133] Accordingly, the second sensor (H2) is positioned at the magnetic boundary (O1, O2) of the first-1 magnet (M1-1) or the first-2 magnet (M1-2) between the first-1 coil (C1-1) and the first-2 coil (C1-2), as in FIG. 6 (a), and can sense changes in the magnetic field due to changes in the magnetic boundary position of the first-1 magnet (M1-1) or the first-2 magnet (M1-2).

[0134] In addition, as shown in Fig. 6(b), the second sensor (H2) may be positioned at the magnetic pole boundary (O2') of the first-second magnet (M1-2) on the winding boundary side of the first-second coil (C1-2) to sense changes in the magnetic field due to changes in the magnetic pole boundary position of the first-second magnet (M1-2).

[0135] In addition, as shown in Fig. 6 (c), the second sensor (H2) may be positioned at the magnetic pole boundary (O1') of the first-1 magnet (M1-1) on the winding boundary side of the first-1 coil (C1-1) to sense changes in the magnetic field due to changes in the magnetic pole boundary position of the first-1 magnet (M1-1).

[0136] Referring to FIG. 7, the first driving unit may be composed of a single first coil (C1) and a single first magnet (M1).

[0137] At this time, the first sensor (H1) can be positioned facing the first magnet (M1) on the winding center side of the first coil (C1).

[0138] In addition, as shown in FIG. 7 (a), the second sensor (H2) may be placed at the boundary (O1"-1) of one side of the magnetic pole of the first magnet (M1) on one side of the winding boundary of the first coil (C1) to sense changes in the magnetic field due to changes in the position of the one side magnetic pole boundary of the first magnet (M1).

[0139] In addition, as shown in Fig. 7 (b), the second sensor (H2) may be placed at the boundary (O1"-2) of the other magnetic pole of the first magnet (M1) on the other side of the winding boundary of the first coil (C1) to sense changes in the magnetic field due to changes in the position of the other magnetic pole boundary of the first magnet (M1).

[0140] As described above, a camera actuator (1) according to one embodiment of the present invention can increase the winding amount of the second coil (C2) of the second driving unit, which requires a large driving force, by positioning a first sensor (H1) and a second sensor (H2) in the first direction so as to sense only the first magnet (M1) of the first driving unit, which is positioned in the first direction among the first direction and the second direction perpendicular to the optical axis direction, where a large driving force is not required or there is no need to increase the driving force. This allows the driving force of the second driving unit to be increased.

[0141] In addition, the first sensor (H1) is positioned to sense the movement distance of the first magnet (M1), and the second sensor (H2) is positioned to sense the change in magnetic quantity on the magnetic boundary of the same first magnet (M1), so that even if the first sensor (H1) and the second sensor (H2) are positioned in the same direction, the movement of the OIS carrier (100) in the first direction and the second direction can be accurately sensed.

[0142] Through this, the camera actuator (1) according to one embodiment of the present invention can achieve maximum driving force even within a limited space, suppress rotational movement of the OIS carrier (100), and increase OIS driving precision.

[0143]

[0144] FIG. 8 is a schematic diagram illustrating sensing according to the movement of an OIS carrier in a first direction in a camera actuator according to an embodiment of the present invention. FIG. 8 describes the arrangement of a first sensor (H1; H1-1, H1-2) and a second sensor (H2) as an example, as in FIG. 5 and FIG. 6 (a).

[0145] The first-1 sensor (H1-1) senses the distance between itself and the first-1 magnet (M1-1) facing it. At this time, when the OIS carrier (100) moves linearly by r1 in the first direction, the first-1 sensor (H1-1) senses that the distance between itself and the first-1 magnet (M1-1) has changed from a1 to a1'.

[0146] Then, the first-2 sensor (H1-2) senses the distance between itself and the facing first-2 magnet (M1-2). At this time, when the OIS carrier (100) moves linearly by r1 in the first direction, the first-2 sensor (H1-2) senses that the distance between itself and the first-2 magnet (M1-2) has changed from a2 to a2'.

[0147] At this time, the value sensed by the first-1 sensor (H1-1) and the distance interval value sensed by the first-2 sensor (H1-2) are the same, and accordingly, it can be seen that the OIS carrier (100) has moved by r1 in the first direction.

[0148] Meanwhile, simultaneously with the sensing of the first sensor (H1), the second sensor (H2) senses a change in the magnetic field due to a change in the position of the magnetic pole boundary (O1, O2) of the first magnet (M1) facing the first magnet (M1), specifically the first-1 magnet (M1-1) or the first-2 magnet (M1-2).

[0149] In FIG. 8, it can be seen that there is no change in the magnetic field on the first magnet (M1) magnetic field boundary sensed by the second sensor (H2), and accordingly, the OIS carrier (100) is in a state of being linearly moved by r1 in the first direction without being rotated.

[0150]

[0151] FIG. 9 is a schematic diagram illustrating sensing according to the movement of an OIS carrier in a second direction in a camera actuator according to an embodiment of the present invention. FIG. 9 explains the arrangement of a first sensor (H1; H1-1, H1-2) and a second sensor (H2) as an example, as in FIG. 5 and FIG. 6 (a).

[0152] The second sensor (H2) senses a change in the magnetic field due to a change in the position of the magnetic pole boundary (O1, O2) of the first magnet (M1) facing the first magnet (M1), specifically the first-1 magnet (M1-1) or the first-2 magnet (M1-2).

[0153] At this time, when the OIS carrier (100) has moved linearly by r2 in the second direction, the second sensor (H2) senses the change in the magnetic field caused by the change in the position of the magnetic field boundary of the first magnet (M1) and senses that the OIS carrier (100) has moved by r2 in the second direction.

[0154] At this time, the first-1 sensor (H1-1) senses the distance between itself and the first-1 magnet (M1-1) facing it, and the first-2 sensor (H1-2) senses the distance between itself and the first-2 magnet (M1-2) facing it.

[0155] At this time, it can be confirmed that there is no change in the sensing value sensed by the first-1 sensor (H1-1) and the first-2 sensor (H1-2) compared to FIG. 5, and accordingly, it can be seen that the OIS carrier (100) is in a state of being linearly moved by r2 in the second direction without being rotated.

[0156]

[0157] FIG. 10 is a schematic diagram illustrating sensing according to the rotational movement of an OIS carrier in a camera actuator according to an embodiment of the present invention. FIG. 10 describes the arrangement of a first sensor (H1; H1-1, H1-2) and a second sensor (H2) as an example, as in FIG. 5 and FIG. 6 (a).

[0158] Depending on the function implementation, the OIS carrier (100) may generate posture defects such as rotation and tilt. For example, although illustrated excessively for illustrative purposes, as shown in FIG. 10, the OIS carrier (100) may rotate.

[0159] At this time, the first-1 sensor (H1-1) senses the distance between itself and the facing first-1 magnet (M1-1), and as the OIS carrier (100) rotates, the first-1 sensor (H1-1) senses that the OIS carrier (100) has changed from a1 to a1' in the first direction.

[0160] And, the first-2 sensor (H1-2) senses the distance between itself and the facing first-2 magnet (M1-2), and as the OIS carrier (100) rotates, the first-2 sensor (H1-2) senses that the OIS carrier (100) has changed from a2 to a2' in the first direction.

[0161] At this time, since the distance interval from a1 to a1' sensed by the first-1 sensor (H1-1) and the distance interval from a2 to a2' sensed by the first-2 sensor (H1-2) are different sensed values, the camera actuator (1) recognizes that the OIS carrier (100) has not been able to move linearly in the first direction and generates a correction control signal to control it.

[0162] At the same time, the second sensor (H2) senses a change in the magnetic field due to a change in the position of the first-1 magnet (M1-1) or the first-2 magnet (M1-2) among the first magnets (M1) facing each other.

[0163] With the OIS carrier (100) in a rotated state, the second sensor (H2) senses a change in the magnetic field of the magnetic field boundary of the first magnet (M1) and senses that the position of the magnetic field boundary of the first magnet (M1) has changed, and the camera actuator (1) generates a correction control signal for the movement of the OIS carrier (100) in the second direction to control it.

[0164] Through this, the camera actuator (1) according to one embodiment of the present invention can stably perform the function by correcting and controlling the movement of the OIS carrier (100) through the sensing values ​​of the first sensor (H1) and the second sensor (H2) even if the OIS carrier (100) has a posture defect such as rotation or tilt.

[0165]

[0166] As described above, a camera actuator (1) according to one embodiment of the present invention may have a first sensor (H1) and a second sensor (H2) positioned to sense only the magnet of a driving unit located in one of the first and second directions, which are perpendicular to the optical axis direction, where a significant increase in driving force is not required. By doing so, the amount of winding of the coil in the other direction where an increase in driving force is required can be increased to increase the driving force.

[0167] Accordingly, it is possible to achieve miniaturization and slimming of the camera actuator (1) while generating maximum driving force within a limited space.

[0168] In addition, by providing sensing sensors (H1, H2) to sense only the magnet in one direction, either the optical axis direction or the direction perpendicular to it, the OIS driving precision can be improved even if an assembly error between parts occurs on one side.

[0169] For example, the first sensor (H1) is positioned to sense the movement distance of the first magnet (M1), and the second sensor (H2) is positioned to sense the change in magnetic quantity according to the change in the magnetic boundary position of the first magnet (M1), so that even if the first sensor (H1) and the second sensor (H2) are positioned in the same direction, the movement of the OIS carrier (100) in the first direction and the second direction can be accurately sensed.

[0170] In addition, by arranging the first sensor (H1) and the second sensor (H2) in the same direction to detect only the change of the first magnet (M1), the driving precision of the OIS can be improved through accurate sensing of posture defects such as rotation and tilt of the OIS carrier that moves slightly despite the occurrence of assembly tolerance of the second magnet (M2).

[0171] In addition, the camera actuator (1) of the present invention can achieve miniaturization or slimming of the device by reducing the coil size in the direction where less driving force is required and increasing the coil size in the direction where more driving force is required, while also maximizing the driving force within a limited space to improve OIS driving characteristics.

[0172] Although embodiments of the present invention have been described, the spirit of the present invention is not limited by the embodiments presented in this specification. Those skilled in the art who understand the spirit of the present invention may easily propose other embodiments within the scope of the same spirit by adding, changing, deleting, or adding components, and such are also to be considered to fall within the scope of the spirit of the present invention.

Claims

1. An OIS carrier moving in a first direction or a second direction perpendicular to the optical axis direction; A base accommodating the above OIS carrier; A first driving unit comprising a first magnet provided on a first directional side of the OIS carrier and a first coil disposed facing the first magnet; A second driving unit comprising a second magnet provided on the second directional side of the OIS carrier and a second coil disposed facing the second magnet; At least one first sensor disposed facing the first magnet and sensing the distance between the first coil and the first magnet; and, A camera actuator comprising: at least one second sensor disposed at the boundary of the magnetic field of the first magnet and sensing a change in the magnetic field according to a change in the position of the magnetic field boundary of the first magnet.

2. In Paragraph 1, The first sensor senses the amount of movement variation of the OIS carrier in the first direction according to the variation in the distance interval between the first magnets, and The second sensor is a camera actuator that senses the amount of movement variation of the OIS carrier in the second direction according to the change in the magnetic field caused by the change in the position of the magnetic field boundary of the first magnet.

3. In Paragraph 1, The first sensor is positioned at the center of the winding of the first coil, and The second sensor is a camera actuator positioned at the winding boundary of the first coil.

4. In Paragraph 1, The first coil comprises a first-1 coil and a first-2 coil arranged adjacent to the first-1 coil in a second direction, and A camera actuator comprising the first magnet, which includes a first magnet facing the first-1 coil and a first-2 magnet facing the first-2 coil.

5. In Paragraph 4, The first sensor above is, A first-1 sensor disposed on the center side of the winding of the first-1 coil, and A camera actuator comprising a first-2 sensor positioned at the center of the winding of the first-2 coil.

6. In Paragraph 5, The second sensor mentioned above is, A camera actuator disposed at the boundary of the magnetic poles of the first-1 magnet or the first-2 magnet between the first-1 coil and the first-2 coil, and sensing a change in the magnetic field due to a change in the position of the magnetic pole boundary of the first-1 magnet or the first-2 magnet.

7. In Paragraph 5, The second sensor mentioned above is, A camera actuator positioned at the boundary of the magnetic pole of the first-1 magnet on the winding boundary side of the first-1 coil, and sensing a change in the magnetic field due to a change in the position of the magnetic pole boundary of the first-1 magnet.

8. In Paragraph 5, The second sensor mentioned above is, A camera actuator positioned at the boundary of the magnetic pole of the first-2 magnet on the winding boundary side of the first-2 coil, and sensing a change in the magnetic field due to a change in the position of the magnetic pole boundary of the first-2 magnet.

9. In Paragraph 1, An AF carrier that is accommodated in the base and moves in the optical axis direction, including the OIS carrier; and, A camera actuator comprising: an AF driving unit including an AF coil provided on the base and an AF magnet provided on the AF carrier facing the AF coil.

10. In Paragraph 9, A camera actuator further comprising a middle guide interposed between the AF carrier and the OIS carrier and supporting the movement of the OIS carrier.

11. In Paragraph 1, The first sensor and the second sensor are, A camera actuator composed of a Hall sensor.

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