Actuator for driving the reflector

Abstract

The present invention provides an actuator for driving a reflector, which includes: a moving frame, including a reflector configured to reflect or refract light to a lens and a first magnet; a first supporting frame, configured to provide a space for the moving frame to move; a first driving coil, configured to generate an electromagnetic force in the first magnet to rotationally move the moving frame in a first direction based on the first supporting frame; a first rotating guide, between the moving frame and the first supporting frame, and having an arc shape, so that the moving frame rotates in the first direction; and a first ball, inside the first rotating guide, wherein the center of curvature of the first rotating guide corresponds to the rotation center of the reflector.

Description

Technical Field

[0001] The present invention relates to an actuator for driving a reflector, and more particularly, to an actuator for driving a reflector that realizes optical image stabilization (OIS) and the like by improving a ball guide structure. Background Art

[0002] With the advancement of hardware technology for image processing and the increasing needs of users for image capture, etc., functions such as auto focus (AF) and optical image stabilization (OIS) have been implemented in camera modules installed on mobile terminals such as mobile phones or smart phones, as well as independent camera devices.

[0003] The AF (auto focus control) function is a function of linearly moving a carrier having a lens, etc. in the optical axis direction to adjust the focal distance from the subject so that a clear image is produced by an image sensor (CMOS, CCD, etc.) provided at the rear end of the lens.

[0004] In addition, the OIS function refers to a function of improving image clarity by adaptively moving a carrier (frame) on which a lens is mounted in a direction to compensate for the shake when the lens shake occurs due to hand shake.

[0005] As one of the representative methods for realizing the AF or OIS function, there is a method in which a magnet (coil) is installed in a moving body (carrier) and a coil (magnet) is installed in a fixed body (housing, another type of carrier, etc.) and then an electromagnetic force is generated between the coil and the magnet to move the moving body in the optical axis direction or in a direction perpendicular to the optical axis.

[0006] In addition, recently, a zoom lens having specifications such as being able to variably adjust a focal length or capture a distant image in order to meet higher user needs and provide user convenience in more diverse ways is mounted on a mobile terminal.

[0007] The zoom lens has a structure in which a plurality of lenses or lens groups are arranged side by side, or has a feature that the length of the lens itself based on the optical axis direction is long, and thus a large installation space should be provided in the mobile terminal.

[0008] Recently, in order to organically combine the physical characteristics of a zoom lens with the geometric characteristics of a mobile terminal, an actuator or a camera module having a physical structure of refracting light of a subject using a reflector provided on a front end of a lens has been disclosed.

[0009] An actuator using a reflector or the like does not correct and move the lens according to hand shake, but implements OIS for hand shake by moving a reflector that reflects light of a subject in the direction of the lens in one or two axes.

[0010] Generally, the actuator has a structure in which a guide rail is formed in each of a moving body (a physical object having a reflector) and a fixed body, a plurality of balls are arranged therebetween, and thus the moving body rotationally moves along the guide rail while being supported by the balls.

[0011] However, in related-art actuators, the center of curvature of the guide rail and the center of rotation of the reflector do not coincide with each other. Therefore, even if the same driving force is applied to the magnet, the amount of rotation of the moving body varies depending on the position of the moving body, and a separate compensation algorithm must be applied to compensate for the amount of rotation for each position. Summary of the Invention

[0012] Technical issues

[0013] The present invention relates to a design in which the center of curvature of the rotation guide and the center of rotation of the reflector coincide with each other, and the amount of rotation of the moving body is the same for the same driving force regardless of the position of the moving body.

[0014] Other purposes and beneficial effects of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention.In addition, the purposes and beneficial effects of the present invention can be achieved through the configurations described in the claims and the combination of the configurations.

[0015] Workaround

[0016] According to one aspect of the present invention, an actuator for driving a reflector is provided, which includes: a moving frame including a reflector configured to reflect or refract light to a lens and a first magnet; a first supporting frame configured to provide a space for the moving frame to move; a first driving coil configured to generate an electromagnetic force in the first magnet to rotationally move the moving frame based on the first supporting frame; a first rotating guide between the moving frame and the first supporting frame and having an arc shape so that the moving frame rotates in a first direction; and a first ball inside the first rotating guide, wherein the center of curvature of the first rotating guide corresponds to the center of rotation of the reflector.

[0017] Therein, the first supporting frame may include a second magnet.

[0018] In addition, the actuator for driving the reflector of the present invention may also include: a second support frame, configured to provide a space for the movement of the first support frame; a second driving coil, configured to generate an electromagnetic force in the second magnet to rotationally move the first support frame in a second direction based on the second support frame; a second rotating guide, between the first support frame and the second support frame, and having an arc shape, so that the first support frame rotates in the second direction; and a second ball, arranged inside each second rotating guide, wherein the center of curvature of the second rotating guide corresponds to the rotation center of the reflector.

[0019] Furthermore, the first rotation guide may include a first guide rail provided on an inner surface of the first supporting frame parallel to the optical axis direction; and a second guide rail provided on an outer surface of the moving frame to correspond to the first guide rail.

[0020] Furthermore, the first rotation guide may include a guide rail provided on an outer surface of the moving frame parallel to the optical axis direction; and a holder provided on an inner surface of the first supporting frame to correspond to the guide rail.

[0021] Furthermore, the first rotation guide may include a guide rail provided on an inner surface of the first support frame parallel to the optical axis direction; and a holder provided on an outer surface of the moving frame to correspond to the guide rail.

[0022] Furthermore, the retainer may include a plurality of retainers arranged along an arc shape.

[0023] Furthermore, the second rotation guide may include a first guide rail provided on an outer surface of the first support frame perpendicular to the optical axis direction; and a second guide rail provided on an inner surface of the second support frame to correspond to the first guide rail.

[0024] Furthermore, the second rotation guide may include a guide rail provided on an outer surface of the first support frame perpendicular to the optical axis direction; and a holder provided on an inner surface of the second support frame to correspond to the guide rail.

[0025] Furthermore, the second rotation guide may include a guide rail provided on an inner surface of the second support frame perpendicular to the optical axis direction; and a holder provided on an outer surface of the first support frame to correspond to the guide rail.

[0026] Furthermore, the retainer may include a plurality of retainers arranged along an arc shape.

[0027] Furthermore, the first rotation guide and the second rotation guide are configured as a pair facing each other based on the center of curvature.

[0028] In addition, the actuator for driving the reflector of the present invention may also include: a third magnet, arranged in the first supporting frame; and a yoke, arranged in the moving frame to generate an attractive force in the third magnet, wherein the centers of the third magnet and the yoke correspond to the center of curvature of the first rotating guide.

[0029] Furthermore, the actuator for driving a reflector of the present invention may further include a yoke that generates an attractive force in the second magnet, wherein centers of the second magnet and the yoke correspond to a center of curvature of the second rotation guide.

[0030] In addition, the actuator for driving a reflector of the present invention may further include: a first Hall sensor and a second Hall sensor, which are arranged at the inner center of the first driving coil.

[0031] Furthermore, the second driving coil may include a first sub-driving coil configured to rotationally move the first supporting frame in a first rotational direction; and a second sub-driving coil configured to rotationally move the first supporting frame in a second rotational direction opposite to the first rotational direction.

[0032] In addition, the actuator for driving a reflector of the present invention may further include: a first Hall sensor and a second Hall sensor, each arranged at an inner edge of the first sub-driving coil and the second sub-driving coil, and each arranged at an edge farthest from the center of curvature of the second rotating guide. Summary of the Invention

[0034] According to the present invention, the center of curvature of the rotation guide coincides with the rotation center of the reflector. Therefore, for the same driving force, the rotation amount of the moving body can be the same regardless of the position of the moving body.

[0035] Furthermore, according to the present invention, the position of the ball bearings, which are positioned between the mobile body and the fixed body to guide the mobile body's rotational movement, is precisely determined, regardless of the OIS drive. This results in a more balanced physical support according to the mobile body's rotational movement, and thus, the phenomenon of the mobile body tilting can be fundamentally prevented.

[0036] Furthermore, according to the present invention, a plurality of balls are provided, but the spacing between the balls can be designed to optimize the rotational movement of the moving body, and thus due to the stable physical support, more stable physical support and the accuracy of OIS can be further improved.

[0037] In addition, according to the present invention, a relatively large ball can be provided in an actuator having the same size, thereby improving the performance of the ball. In addition, the adverse physical effects generated between the ball and the guide rail can be further suppressed to improve the driving performance and further increase the durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a perspective view of an overall assembly of an actuator for driving a reflector according to one embodiment of the present invention.

[0039] Figure 2 and Figure 3 FIG. 1 is an exploded perspective view of an entire actuator for driving a reflector according to an embodiment of the present invention.

[0040] Figure 4 and Figure 5 is an exploded perspective view of components coupled to a moving frame according to a first embodiment of the present invention.

[0041] Figure 6 is an exploded perspective view of components coupled to a moving frame according to a second embodiment of the present invention.

[0042] Figure 7 and Figure 8 is an exploded perspective view of components coupled to a first support frame according to a first embodiment of the present invention.

[0043] Figure 9 and Figure 10 is an exploded perspective view of components coupled to a first support frame according to a second embodiment of the present invention.

[0044] Figure 11 and Figure 12 is an exploded perspective view of components coupled to a second support frame according to a first embodiment of the present invention.

[0045] Figure 13 and Figure 14 is an exploded perspective view of components coupled to a second support frame according to a second embodiment of the present invention.

[0046] Figure 15 is a perspective view of an overall assembly of a circuit board according to one embodiment of the present invention.

[0047] Figure 16 A plan view of a circuit board according to one embodiment of the present invention is shown.

[0048] Figure 17 is a view for describing structural features of a first rotation guide of an actuator for driving a reflector according to one embodiment of the present invention.

[0049] Figure 18 A view for describing a driving method using a first rotation guide of an actuator for driving a reflector according to one embodiment of the present invention is shown.

[0050] Figure 19 is a view for describing structural features of a second rotation guide of an actuator for driving a reflector according to one embodiment of the present invention.

[0051] Figure 20 A view for describing a driving method using a second rotation guide of an actuator for driving a reflector according to one embodiment of the present invention is shown. DETAILED DESCRIPTION

[0052] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before the description begins, the terms or words used in this specification and claims should not be interpreted as limited to their common meanings or dictionary meanings, and based on the principle that the inventor can appropriately define the concept of the term in order to best describe his invention, these terms or words should be interpreted as meanings and concepts consistent with the technical concept of the present invention.

[0053] Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most exemplary embodiments of the present invention and do not represent all technical concepts of the present invention, and therefore, it should be understood that various equivalents and modifications of alternative embodiments and configurations may exist in this application.

[0054] Figure 1 is a perspective view of an overall assembly of an actuator for driving a reflector according to one embodiment of the present invention.

[0055] like Figure 1 As shown in , the actuator 100 for driving a reflector according to one embodiment of the present invention can of course be implemented as a single device and can be implemented in the form of a camera module including a lens assembly, a lens driving module that implements autofocus of the lens assembly, an image sensor, etc. Here, when the actuator 100 for driving a reflector is implemented in the form of a camera module, the lens assembly can be located below the actuator 100 for driving a reflector.

[0056] According to the present invention, object light is not directly introduced into the lens assembly, and is introduced into the lens assembly after the path of the light is changed (refracted, reflected, etc.) by the reflector 110 provided in the actuator 100 for driving the reflector of the present invention.

[0057] As described above, the actuator 100 for driving the reflector according to one embodiment of the present invention is configured so that light is introduced into the lens assembly after the path of the light is refracted by the reflector 110. Therefore, since the lens assembly itself does not need to be installed in the thickness direction of the mobile terminal, even when a lens having a long physical characteristic in the optical axis direction (such as a zoom lens) is installed on the mobile terminal, the thickness of the mobile terminal does not increase, and thus the size of the mobile terminal can be reduced.

[0058] like Figure 1 , the path of light from the outside is path Z1, and the path of light introduced from the outside by being refracted or reflected by the reflector 110 and introduced into the lens assembly is path Z. In the following description, the Z-axis direction, that is, the direction along which light is introduced into the lens assembly, is referred to as an optical axis or even an optical axis direction.

[0059] The reflector 110 may be one selected from a mirror and a prism, or a combination of a mirror and a prism, and may further be implemented as one of various members capable of changing light introduced from the outside to an optical axis direction.

[0060] The lens assembly may be a zoom lens, in which may include not only a single lens but also a plurality of lenses or lens groups, or may include optical components such as prisms or mirrors, and when the lens assembly is composed of a zoom lens or a zoom lens barrel, the lens assembly may have a shape extending in the optical axis direction.

[0061] An image sensor such as a CCD or CMOS that converts an optical signal into an electrical signal may be provided below the lens assembly based on the optical axis direction, and a filter for blocking or transmitting an optical signal of a specific frequency band may also be provided.

[0062] As will be described in detail below, when shaking occurs due to hand shaking, etc. based on a first direction (Y-axis direction, vertical direction) and a second direction (X-axis direction, horizontal direction) perpendicular to the optical axis, the actuator 100 for driving the reflector of the present invention can achieve optical image stabilization (OIS) in the first direction and the second direction by rotationally moving the reflector 110 in the direction of compensating for the movement.

[0063] Figure 2 and Figure 3 FIG. 1 is an exploded perspective view of an entire actuator for driving a reflector according to an embodiment of the present invention.

[0064] like Figure 2 and Figure 3As shown in , the actuator 100 for driving a reflector according to an embodiment of the present invention may include a reflector 110 , a moving frame 120 , a first supporting frame 130 , a second supporting frame 140 , a circuit board 150 , and a housing 165 .

[0065] Here, the reflector 110 is installed in the moving frame 120, and the first supporting frame 130 is accommodated in the second supporting frame 140. In addition, the moving frame 120 in which the reflector 110 is installed is seated on the first supporting frame 130 and accommodated in the second supporting frame 140.

[0066] In addition, the circuit board 150 is coupled to the outer surface of the second support frame 140 , and the housing 165 fixes the moving frame 120 , the second support frame 140 , and the circuit board 150 and serves as a shield case.

[0067] As will be described in detail below, the actuator 100 for driving a reflector according to an embodiment of the present invention includes a first rotation guide and a second rotation guide having balls 160 therein.

[0068] Specifically, the first rotating guide is disposed between the mobile frame 120 and the first supporting frame 130 and has an arcuate shape, allowing the mobile frame 120 to rotate in a first direction (Y-axis direction, vertical direction). Furthermore, the second rotating guide is disposed between the first supporting frame 130 and the second supporting frame 140 and has an arcuate shape, allowing the first supporting frame 130 to rotate in a second direction (X-axis direction, horizontal direction). Here, at least one of the centers of curvature of the first and second rotating guides coincides with the rotation center of the reflector 110.

[0069] Thus, preferably, the curvature centers of the first and second rotation guides coincide with the rotation center of the reflector 110. However, the present invention is not limited thereto, and even when the centers partially move due to manufacturing tolerances, etc., it falls within the scope of the present invention.

[0070] Figure 4 and Figure 5 is an exploded perspective view of components coupled to a moving frame according to a first embodiment of the present invention, and Figure 6 is an exploded perspective view of components coupled to a moving frame according to a second embodiment of the present invention.

[0071] like Figure 4 and Figure 5 As shown in , the moving frame 120 may be provided with a reflector 110 , a first magnet 122 , and a first yoke 125 .

[0072] The movable frame 120 provides a mounting surface on which the reflector 110 is mounted. A first mounting groove 121 is formed on an outer surface perpendicular to the optical axis direction, and a second mounting groove 124 and a first guide rail 123a having an arc shape are formed on an outer surface parallel to the optical axis direction. Here, the first guide rail 123a can be provided as a pair of first guide rails 123a facing each other based on the center of curvature of the first rotating guide.

[0073] The first magnet 122 is installed in the first installation groove 121, and the first yoke 125 is installed in the second installation groove 124. In addition, a plurality of balls 160 are located in the first guide rail 123a. Here, the center of the first yoke 125 coincides with the center of curvature of the first rotation guide.

[0074] In addition, if Figure 6 As shown in , a plurality of first retainers 123b may be provided instead of the first guide rail 123a. Here, the first retainer 123b may be formed in plurality and may be provided along an arc shape, and the ball 160 is located inside each first retainer 123b.

[0075] Figure 7 and Figure 8 is an exploded perspective view of components coupled to a first support frame according to a first embodiment of the present invention, and Figure 9 and Figure 10 is an exploded perspective view of components coupled to a first support frame according to a second embodiment of the present invention.

[0076] like Figure 7 and Figure 8 As shown in , the first supporting frame 130 provides a moving space for the moving frame 120 and may include a second magnet 135 and a third magnet 136 .

[0077] The first supporting frame 130 may include a first plate 130 a parallel to the optical axis direction and a second plate 130 b perpendicular to the optical axis direction.

[0078] The first supporting frame 130 includes a third mounting groove 132 formed inside the first plate 130a (i.e., formed in the inner surface of the first supporting frame 130 parallel to the optical axis direction), and a second guide rail 133a having an arc shape corresponding to the first guide rail 123a of the moving frame 120. Here, the second guide rail 133a may be provided as a pair of second guide rails 133a facing each other based on the center of curvature of the first rotating guide.

[0079] When the moving frame 120 and the first supporting frame 130 are coupled to each other, the first guide rail 123a and the second guide rail 133a form a first rotation guide, or the first holder 123b and the second guide rail 133a form a first rotation guide.

[0080] In addition, the first support frame 130 includes a fourth mounting groove 134 and a third guide rail 137a having an arc shape, which are formed outside the second plate 130b, that is, formed on the outer surface of the first support frame 130 perpendicular to the optical axis direction. Here, the third guide rail 137a can be provided as a pair of third guide rails 137a facing each other based on the center of curvature of the second rotation guide.

[0081] The second magnet 135 is installed in the fourth installation groove 134, and the third magnet 136 is installed in the third installation groove 132. In addition, a plurality of balls 160 are located in the second guide rail 133a and the third guide rail 137a. Here, the center of the second magnet 135 coincides with the center of curvature of the second rotating guide.

[0082] In addition, if Figure 9 and Figure 10 As shown in , a plurality of second holders 133b may be provided instead of the second guide rail 133a. In this case, when the mobile frame 120 and the first supporting frame 130 are coupled to each other, the first guide rail 123a and the second holder 133b form a first rotation guide. In addition, a plurality of third holders 137b may be provided instead of the third guide rail 137a.

[0083] Here, each of the second retainer 133 b and the third retainer 137 b may be formed in plural and disposed along an arc shape, and the ball 160 is located inside each retainer.

[0084] Figure 11 and Figure 12 is an exploded perspective view of components coupled to the second support frame according to the first embodiment of the present invention, and Figure 13 and Figure 14 is an exploded perspective view of components coupled to a second support frame according to a second embodiment of the present invention.

[0085] like Figure 11 and Figure 12 As shown in FIG, the second support frame 140 is formed into a box shape, provides a movable space for the first support frame 130, and has openings formed in the Y-axis direction and the optical axis direction, where the Y-axis direction is the light travel path. In addition, the first mounting hole 141 is formed to correspond to the first magnet 122 of the moving frame 120, and the second mounting hole 142 is formed to correspond to the second magnet 135 of the first support frame 130. In addition, the fourth guide rail 147a is formed to correspond to the third guide rail 137a of the first support frame 130. Here, the fourth guide rail 147a can be formed as a pair of fourth guide rails 147a facing each other based on the center of curvature of the second rotating guide.

[0086] When the first support frame 130 and the second support frame 140 are coupled, the third guide rail 137a and the fourth guide rail 147a form a second rotation guide, or the third holder 137b and the fourth guide rail 147a form a second rotation guide.

[0087] In addition, if Figure 13 and Figure 14 As shown in , a plurality of fourth holders 147b may be provided instead of the fourth guide rail 147a. In this case, when the first support frame 130 and the second support frame 140 are coupled, the third guide rail 137a and the fourth holder 147b form a second rotation guide.

[0088] Here, the fourth retainer 147 b may be formed in plurality and disposed along an arc shape, and the ball 160 is located inside each fourth retainer 147 b .

[0089] Figure 15 is a perspective view of an overall assembly of a circuit board according to one embodiment of the present invention, and Figure 16 A plan view of a circuit board according to one embodiment of the present invention is shown.

[0090] like Figure 15 and Figure 16 As shown in , the circuit board 150 may include a first driving coil 151 , a second driving coil 154 , and a first hall sensor 152 , a second hall sensor 153 , a third hall sensor 155 , and a fourth hall sensor 156 .

[0091] The circuit board 150 may include a first circuit board 150a and a second circuit board 150b bent perpendicular to the first circuit board 150a. Here, the second drive coil 154 and the third and fourth Hall sensors 155 and 156 are provided in the first circuit board 150a, and the first drive coil 151 and the first and second Hall sensors 152 and 153 are provided in the second circuit board 150b.

[0092] The circuit board 150 is coupled to the second support frame 140 such that the first driving coil 151 is mounted in the first mounting hole 141 of the second support frame 140 , and the second driving coil 154 is mounted in the second mounting hole 142 of the second support frame 140 .

[0093] Therefore, the first driving coil 151 and the first magnet 122 of the moving frame 120 face each other, and the second driving coil 154 and the second magnet 135 of the first supporting frame 130 face each other.

[0094] The first driving coil 151 generates electromagnetic force in the first magnet 122 provided in the moving frame 120 to rotationally move the moving frame 120 in a first direction (Y-axis direction, vertical direction) based on the first supporting frame 130 .

[0095] The first magnet 122 receives a driving force due to an electromagnetic force from the first driving coil 151 , and the moving frame 120 in which the first magnet 122 is mounted is rotationally moved based on the first supporting frame 130 by the driving force.

[0096] In this regard, the first support frame 130 providing a moving space of the moving frame 120 corresponds to a fixed body from a relative viewpoint based on the moving frame 120 .

[0097] Thus, when the moving frame 120 in which the reflector 110 is mounted rotates based on the first support frame 130 (YZ plane), the reflector 110 physically and rotationally moves together with the moving frame 120, and the position where the light of the object is introduced into the image sensor (not shown) moves by the rotational movement of the reflector 110. Thus, OIS for the first direction is achieved.

[0098] Preferably, the first magnet 122 is installed at the center of the moving frame 120 so that the rotational movement of the moving frame 120 is stably supported and the driving accuracy is improved, and the center of the first magnet 122 is consistent with the rotation center of the reflector 110 in the first direction. However, the present invention is not limited thereto, and even when the center is partially moved due to manufacturing tolerances, etc., it falls within the scope of the present invention.

[0099] The balls 160 are located in the first rotation guide between the moving frame 120 and the first supporting frame 130 , and the moving frame 120 rotationally moves in a state of being in contact with the balls 160 .

[0100] The first yoke 125 provided in the moving frame 120 is made of a magnetic material such as metal, and performs a function of generating an attractive force in the third magnet 136 provided in the first supporting frame 130 .

[0101] By the attraction force generated as described above, the first support frame 130 in which the third magnet 136 is mounted is pulled in the direction in which the first yoke 125 is provided, that is, in the direction of the first support frame 130. Therefore, the moving frame 120 and the ball bearings 160 are pressed against each other, and the ball bearings 160 and the first support frame 130 are pressed against each other.

[0102] In addition, when power is stopped to the first drive coil 151, the first magnetic yoke 125 can also perform the function of returning the moving frame 120 to the original reference position. In order to improve the efficiency of the functional control for the rotational movement of the moving frame 120 and the return to the reference position, the center of the first magnetic yoke 125 is preferably consistent with the center of the third magnet 136, and the shape of the first magnetic yoke 125 is the same as the shape of the third magnet 136.

[0103] The first and second hall sensors 152 and 153 detect the position of the first magnet 122 (specifically, the position of the reflector 110 installed in the moving frame 120 in which the first magnet 122 is provided) using the Hall effect.

[0104] The first Hall sensor 152 and the second Hall sensor 153 can be implemented in the form of a single chip together with a driving driver, where the driving driver uses the output values ​​of the first Hall sensor 152 and the second Hall sensor 153 for feedback control to control the amplitude and direction of the power applied to the first driving coil 151.

[0105] In addition, the present invention includes two first Hall sensors 152 and second Hall sensors 153 to compensate for crosstalk, and when the first Hall sensors 152 and second Hall sensors 153 are disposed at the inner edge of the first drive coil 151, the amount of crosstalk compensation increases as the position of the first magnet 122 changes. To address this issue, the first Hall sensor 152 and second Hall sensor 153 are preferably disposed at the inner center of the first drive coil 151.

[0106] When the first rotation guide includes the first retainer 123b or the second retainer 133b, the moving frame 120 rotationally moves with the rotational movement of the first guide rail 123a or the second guide rail 133a by the balls 160 constrained by the first retainer 123b or the second retainer 133b.

[0107] Specifically, the balls 160 can perform rolling or rotational movement while being accommodated in the first holder 123b or the second holder 133b, and the distance between the balls 160 is kept constant. Therefore, the problems of the related art devices such as support instability, tilting of the moving body, and deterioration of driving accuracy caused by the free movement of the balls can be basically solved.

[0108] Furthermore, in the case of the present invention, since the rolling balls 160 can be spaced apart from each other by an appropriate distance, additional space can be ensured and rolling balls having a relatively large size can be applied.

[0109] Furthermore, it is preferred that the inner surface of the first retainer 123 b or the second retainer 133 b is narrowed inwardly, thereby more effectively achieving point contact with the ball 160 and physical support by the ball 160 .

[0110] The second driving coil 154 generates electromagnetic force in the second magnet 135 provided in the first support frame 130 to rotationally move the first support frame 130 in a second direction (X-axis direction, horizontal direction) based on the second support frame 140 .

[0111] The second magnet 135 receives a driving force by an electromagnetic force from the second driving coil 154 , and the first support frame 130 in which the second magnet 135 is mounted is rotationally moved based on the second support frame 140 by the driving force.

[0112] In this regard, the second support frame 140 providing a movement space of the first support frame 130 corresponds to a fixed body from a relative viewpoint based on the first support frame 130 .

[0113] Thus, when the first support frame 130 in which the moving frame 120 is mounted rotates (XZ plane) based on the second support frame 140, the reflector 110 physically and rotationally moves together with the first support frame 130, and the position where the light of the object is introduced into the image sensor (not shown) is moved by the rotational movement of the reflector 110. Therefore, OIS for the second direction is achieved.

[0114] Preferably, the second magnet 135 is mounted at the center of the first support frame 130 to stably support the rotational movement of the first support frame 130 and improve the driving accuracy, and the center of the second magnet 135 is consistent with the rotation center of the reflector 110 in the second direction. However, the present invention is not limited thereto, and even when the center is partially moved due to manufacturing tolerances, etc., this falls within the scope of the present invention.

[0115] The balls 160 are located in the second rotation guide between the first support frame 130 and the second support frame 140 , and the first support frame 130 rotationally moves in a state of being in contact with the balls 160 .

[0116] Although not shown in the drawings, a second yoke may be provided under the circuit board 150. Here, the second yoke is provided at a position corresponding to the second magnet 135.

[0117] Such a second yoke is made of a magnetic material such as metal, and performs a function of generating an attractive force in the second magnet 135 provided in the first support frame 130 .

[0118] By the attraction force generated as described above, the first support frame 130 in which the second magnet 135 is mounted is pulled in the direction in which the second yoke is provided, that is, in the direction of the second support frame 140. Therefore, the first support frame 130 and the ball bearings 160 are pressed against each other, and the ball bearings 160 and the second support frame 140 are pressed against each other.

[0119] Furthermore, when power is stopped to the first drive coil 151, the second magnetic yoke can also return the first support frame 130 to its original reference position. To improve the efficiency of the functional control for the rotational movement and return to the reference position of the first support frame 130, the center of the second magnetic yoke is preferably aligned with the center of the second magnet 135, and the shape of the second magnetic yoke is the same as that of the second magnet 135.

[0120] The third and fourth hall sensors 155 and 156 detect the position of the second magnet 135 (specifically, the position of the reflector 110 installed in the first support frame 130 in which the second magnet 135 is provided) using the Hall effect.

[0121] The third Hall sensor 155 and the fourth Hall sensor 156 can be implemented in the form of a single chip together with a drive driver, where the drive driver uses the output values ​​of the third Hall sensor 155 and the fourth Hall sensor 156 for feedback control to control the amplitude and direction of the power applied to the second drive coil 154.

[0122] The second drive coil 154 includes a first sub-drive coil 154a and a second sub-drive coil 154b, wherein the first sub-drive coil 154a rotationally moves the first support frame 130 in a first rotation direction (for example, clockwise), and the second sub-drive coil 154b rotationally moves the first support frame 130 in a second rotation direction (for example, counterclockwise) opposite to the first rotation direction.

[0123] Here, in order to increase the output values ​​of the third Hall sensor 155 and the fourth Hall sensor 156, preferably, the third Hall sensor 155 and the fourth Hall sensor 156 are respectively arranged at the inner edges of the first sub-drive coil 154a and the second sub-drive coil 154b, and each is arranged at the edge farthest from the center of curvature of the second rotating guide.

[0124] When the second rotation guide includes the third retainer 137b or the fourth retainer 147b, the first support frame 130 rotationally moves with rotational movement of the third guide rail 137a or the second guide rail 147a by the balls 160 constrained by the third retainer 137b or the fourth retainer 147b.

[0125] Specifically, the balls 160 can perform rolling or rotational movement while being accommodated in the third holder 137b or the fourth holder 147b, and the distance between the balls 160 is kept constant. Therefore, the problems of the related art devices such as support instability, tilting of the moving body, and deterioration of driving accuracy caused by the free movement of the balls can be basically solved.

[0126] Furthermore, in the case of the present invention, since the rolling balls 160 can be spaced apart from each other by an appropriate distance, additional space can be ensured and rolling balls having a relatively large size can be applied.

[0127] Furthermore, it is preferred that the inner surface of the third retainer 137 b or the fourth retainer 147 b is narrowed inwardly, thereby more effectively achieving point contact with the ball 160 and physical support of the ball 160 .

[0128] Figure 17 is a view for describing structural features of a first rotation guide of an actuator for driving a reflector according to one embodiment of the present invention.

[0129] refer to Figure 17 In the actuator 100 for driving a reflector according to one embodiment of the present invention, the curvature center CC1 of the first rotation guide (eg, the first guide rail 123 a ) coincides with the rotation center Cr1 of the reflector 110 in the first direction.

[0130] In addition, when the center of curvature CC1 of the first rotating guide and the rotation center Cr1 of the reflector 110 in the first direction are inconsistent with each other, even when the same driving force is applied to the first magnet 122, the rotation amount of the moving frame 120 is different depending on the position of the moving frame 120, and there is a problem that a separate compensation algorithm should be applied to compensate for the different rotation amounts for each position.

[0131] However, in the actuator 100 for driving a reflector according to an embodiment of the present invention, the center of curvature CC1 of the first rotating guide coincides with the rotation center Cr1 of the reflector 110. Therefore, regardless of the position of the moving frame 120 for the same driving force, since the rotation amount of the moving frame 120 is the same, a separate compensation algorithm is not required.

[0132] Figure 18 A view for describing a driving method using a first rotation guide of an actuator for driving a reflector according to one embodiment of the present invention is shown.

[0133] First, if Figure 18As shown in (a) of FIG. 1 , when the first driving coil 151 generates an electromagnetic force in the first magnet 122 so that the moving frame 120 rotationally moves in a first rotation direction (eg, counterclockwise), the reflector 110 also rotationally moves together.

[0134] Next, if Figure 18 As shown in FIG. 5( b ), when the power supply to the first driving coil 151 is stopped, the moving frame 120 is returned to the initial reference position by the attraction between the first yoke 125 and the third magnet 136 .

[0135] Figure 19 is a view for describing structural features of a second rotation guide of an actuator for driving a reflector according to one embodiment of the present invention.

[0136] refer to Figure 19 In the actuator 100 for driving a reflector according to one embodiment of the present invention, the curvature center CC2 of the second rotation guide (eg, the third guide rail 137 a ) coincides with the rotation center Cr2 of the reflector 110 in the second direction.

[0137] In addition, when the center of curvature CC2 of the second rotating guide and the center of rotation Cr2 of the reflector 110 in the second direction are inconsistent with each other, even when the same driving force is applied to the second magnet 135, the rotation amount of the first supporting frame 130 is different depending on the position of the first supporting frame 130, and there is a problem that a separate compensation algorithm should be applied to compensate for the different rotation amounts for each position.

[0138] However, in the actuator 100 for driving a reflector according to an embodiment of the present invention, the center of curvature CC2 of the second rotation guide coincides with the center of rotation Cr2 in the second direction of the reflector 110. Therefore, regardless of the position of the first support frame 130 for the same driving force, since the rotation amount of the first support frame 130 is the same, a separate compensation algorithm is not required.

[0139] Figure 20 A view for describing a driving method using a second rotation guide of an actuator for driving a reflector according to one embodiment of the present invention is shown.

[0140] First, if Figure 20 As shown in (a), when the second driving coil 154 generates an electromagnetic force in the second magnet 135 so that the first support frame 130 rotationally moves in a first rotation direction (eg, counterclockwise), the moving frame 120 and the reflector 110 also rotationally move together.

[0141] Next, if Figure 20As shown in FIG. 5( b ), when the power supply to the second driving coil 154 is stopped, the first supporting frame 130 is returned to the initial reference position by the attraction between the second yoke and the second magnet 135 .

[0142] The present invention has been described so far with reference to a limited number of embodiments and drawings. However, the present invention is not limited thereto, and it goes without saying that a person skilled in the art can make various modifications and variations within the technical concept of the present invention and the equivalent scope of the appended claims.

[0143] In the above description of the present invention, modifiers such as first and second are merely instrumental conceptual terms used to distinguish components relative to each other, and thus the modifiers should not be construed as terms used to indicate a specific order, priority, etc.

[0144] In order to emphasize or highlight the technical content according to the present invention, the drawings used to describe the present invention and its embodiments may be shown in a slightly exaggerated form. However, it is obvious that, considering the above description and the items shown in the drawings, various types of modifications can be applied to those skilled in the art.

[0145] Industrial Applicability

[0146] The actuator for driving a reflector according to the present invention may be applied to a separate camera device as well as a camera module mounted on a mobile terminal such as a portable phone, a smart phone, etc.

Claims

1. An actuator for driving a reflector, comprising: a moving frame including a reflector configured to reflect or refract light toward the lens and a first magnet; a first supporting frame configured to provide a space for movement of the mobile frame; a first driving coil configured to generate an electromagnetic force in the first magnet to rotationally move the moving frame based on the first supporting frame; a first rotation guide between the moving frame and the first supporting frame and having an arc shape so that the moving frame rotates in a first direction; and first balls arranged inside each of the first rotation guides, The curvature center of the first rotating guide corresponds to the rotation center of the reflector. The first support frame includes a second magnet, The actuator for driving the reflector further comprises: a second support frame configured to provide a space for movement of the first support frame; a second driving coil configured to generate an electromagnetic force in the second magnet to rotationally move the first support frame in a second direction based on the second support frame; a second rotation guide between the first supporting frame and the second supporting frame and having an arc shape so that the first supporting frame rotates in the second direction; and second balls arranged inside each of the second rotation guides, The curvature center of the second rotation guide corresponds to the rotation center of the reflector.

2. The actuator for driving a reflector according to claim 1, wherein: The first rotation guide comprises: a first guide rail provided on an inner surface of the first supporting frame parallel to the optical axis; and The second guide rail is arranged on the outer surface of the moving frame to correspond to the first guide rail.

3. The actuator for driving a reflector according to claim 1, wherein: The first rotation guide comprises: a guide rail, provided on an outer surface of the movable frame parallel to the optical axis; and A retainer is provided on an inner surface of the first supporting frame to correspond to the guide rail.

4. The actuator for driving a reflector according to claim 1, wherein: The first rotation guide comprises: a guide rail provided on an inner surface of the first supporting frame parallel to the optical axis direction; and A retainer is provided on an outer surface of the moving frame to correspond to the guide rail.

5. The actuator for driving a reflector according to claim 3 or 4, wherein: The retainer includes a plurality of retainers arranged along the arc shape.

6. The actuator for driving a reflector according to claim 1, wherein: The second rotation guide comprises: a first guide rail provided on an outer surface of the first supporting frame perpendicular to the optical axis; and The second guide rail is provided on the inner surface of the second supporting frame to correspond to the first guide rail.

7. The actuator for driving a reflector according to claim 1, wherein: The second rotation guide comprises: a guide rail provided on an outer surface of the first supporting frame perpendicular to the optical axis; and A retainer is provided on an inner surface of the second supporting frame to correspond to the guide rail.

8. The actuator for driving a reflector according to claim 1, wherein: The second rotation guide comprises: a guide rail provided on an inner surface of the second supporting frame perpendicular to the optical axis; and A retainer is provided on an outer surface of the first supporting frame to correspond to the guide rail.

9. The actuator for driving a reflector according to claim 7 or 8, wherein: The retainer includes a plurality of retainers arranged along the arc shape.

10. The actuator for driving a reflector according to claim 1, wherein: The first rotation guide and the second rotation guide are configured as a pair facing each other based on the center of curvature.

11. The actuator for driving a reflector according to claim 1 , further comprising: a third magnet disposed in the first supporting frame; as well as a magnetic yoke provided in the moving frame to generate an attractive force in the third magnet, The centers of the third magnet and the magnetic yoke correspond to the center of curvature of the first rotating guide.

12. The actuator for driving a reflector according to claim 1, further comprising: a magnetic yoke that generates an attractive force in the second magnet, The centers of the second magnet and the yoke correspond to the center of curvature of the second rotating guide.

13. The actuator for driving a reflector according to claim 1, further comprising: The first Hall sensor and the second Hall sensor are arranged at the inner center of the first driving coil.

14. The actuator for driving a reflector according to claim 1, wherein: The second driving coil includes: a first sub-driving coil configured to rotationally move the first support frame in a first rotational direction; and The second sub driving coil is configured to rotationally move the first support frame in a second rotation direction opposite to the first rotation direction.

15. The actuator for driving a reflector according to claim 14, further comprising: The first and second Hall sensors are each arranged at an inner edge of the first and second sub-driving coils, and each is arranged at an edge farthest from a center of curvature of the second rotating guide.

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