Lens driving device, camera device, and optical device

Abstract

The present embodiment relates to a lens driving device comprising: a housing; a lens holder disposed on the housing; a magnet disposed on the lens holder; a coil interacting with the magnet; a ball disposed between the housing and the lens holder; and a yoke disposed on the housing and having an attractive force interacting with the magnet, wherein the shortest distance between the yoke and the optical axis is shorter than the shortest distance between the magnet and the optical axis.

Description

Lens actuators, camera devices and optical instruments

[0001] The present embodiment relates to a lens driving device, a camera device, and an optical device.

[0002] Modern smartphones are equipped with cameras capable of taking high-resolution photos and videos.

[0003] In particular, recent smartphone cameras have been equipped with an autofocus function that automatically adjusts focus based on the distance from the subject. This autofocus function can be performed by moving the lens along the optical axis relative to the image sensor. Accordingly, the lens actuator may be equipped with a ball that guides the movement of the moving part where the lens is positioned. At this time, the attractive force between a magnet and a yoke can be utilized to hold the ball between the fixed part and the moving part.

[0004] However, in this case, the problem of the lens rolling may occur due to the moment generated by the ball.

[0005] (Patent Document 1) KR 10-2015-0118005 A

[0006] The present embodiment seeks to provide a lens driving device that minimizes the moment generated by a ball. In other words, the present invention seeks to provide a lens driving device that minimizes the rolling, or rotation, of the lens.

[0007] Furthermore, the present embodiment aims to provide a lens driving device that minimizes the amount of driving current used by preventing pre-load from being applied to a moving part.

[0008] Alternatively, a variant embodiment seeks to provide a lens actuator in which impact noise is minimized by applying a preload to the moving part.

[0009] A lens driving device according to the present embodiment includes a housing; a lens holder disposed on the housing; a magnet disposed on the lens holder; a coil interacting with the magnet; a ball disposed between the housing and the lens holder; and a yoke disposed on the housing and having an attractive force with the magnet, wherein a shortest distance between the yoke and the optical axis may be shorter than a shortest distance between the magnet and the optical axis.

[0010] The lens holder can press the ball toward the housing by the attractive force between the magnet and the yoke.

[0011] The magnet may include an outer surface facing the coil and an inner surface opposite the outer surface, and the shortest distance between the ball and the inner surface of the magnet may be shorter than the shortest distance between the ball and the outer surface of the magnet.

[0012] The shortest distance between the ball and the yoke may be shorter than the shortest distance between the ball and the magnet.

[0013] The magnet has an outer surface facing the coil, and the ball can overlap the yoke in a first direction that is perpendicular to the optical axis and parallel to the outer surface of the magnet.

[0014] The magnet may include a first portion that overlaps the ball in the first direction and a second portion that does not overlap the ball in the first direction.

[0015] The magnet has an outer surface facing the coil, and the ball can overlap the coil in a second direction that is perpendicular to the optical axis and perpendicular to the outer surface of the magnet.

[0016] The magnet may be placed between the yoke and the coil in a direction perpendicular to the optical axis.

[0017] The magnet and the coil move the lens holder in the optical axis direction, and the ball may include a plurality of balls that overlap in the optical axis direction.

[0018] The lens holder may include a first side wall, a first groove formed in an outer surface of the first side wall and in which the magnet is disposed, and a second groove formed in an inner surface of the first side wall and in which the ball is disposed.

[0019] The above yoke includes a first yoke and a second yoke that are spaced apart from each other, and each of the first yoke and the second yoke includes a first portion and a second portion that protrudes inwardly from the first portion, and in the optical axis direction, the length of the first portion may be longer than the length of the second portion.

[0020] The above yoke may be a square plate shape arranged parallel to the optical axis.

[0021] The above yoke includes a first part and a second part that are arranged long in the optical axis direction, and a third part that connects the lower part of the first part and the lower part of the second part, and the upper part of the first part and the upper part of the second part may not be connected to each other.

[0022] A camera device according to the present embodiment may include a printed circuit board; an image sensor disposed on the printed circuit board; the lens driving device disposed on the printed circuit board; and a lens coupled to the lens driving device.

[0023] An optical device according to the present embodiment may include a main body; the camera device disposed in the main body; and a display disposed in the main body and outputting at least one of an image and a video captured by the camera device.

[0024] This embodiment can minimize the moment generated by the ball. This can minimize the rolling or rotational phenomenon of the lens.

[0025] Furthermore, through this embodiment, the amount of driving current used can be minimized because no pre-load is applied to the moving part.

[0026] Alternatively, a preload may be applied to the moving part through a variation to minimize impact noise generation.

[0027] Fig. 1 is a perspective view of a lens driving device according to the present embodiment.

[0028] Figure 2 is a cross-sectional view taken along line AA of Figure 1.

[0029] Figure 3 is an enlarged view of area B of Figure 2.

[0030] Fig. 4 is a cross-sectional view of the lens driving device according to the present embodiment, cut perpendicular to the optical axis and viewed from above.

[0031] Fig. 5 is an exploded perspective view of a lens driving device according to the present embodiment.

[0032] Fig. 6 is a perspective view of a lens driving device according to the present embodiment with the cover member omitted.

[0033] Fig. 7 is a perspective view showing the housing and related configuration of the lens driving device according to the present embodiment.

[0034] Fig. 8 is a cross-sectional view showing a ball and a yoke arranged in a housing of a lens driving device according to the present embodiment.

[0035] Fig. 9 is an exploded perspective view of the housing and substrate of the lens driving device according to the present embodiment.

[0036] Fig. 10 is a perspective view showing a lens holder and related configuration of a lens driving device according to the present embodiment.

[0037] Fig. 11 is a bottom perspective view of the lens holder and related components of the lens driving device according to the present embodiment, viewed from a different direction than Fig. 10.

[0038] Fig. 12 (a) is a cross-sectional view showing an initial state in which no current is applied to the coil of the lens driving device according to the present embodiment, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke.

[0039] Fig. 13 (a) is a cross-sectional view showing an initial state in which no current is applied to the coil of the lens driving device according to the first modified example, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke.

[0040] Figure 14 (a) is a cross-sectional view showing an initial state in which no current is applied to the coil of the lens driving device according to the second modified example, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke.

[0041] Fig. 15 is a cross-sectional view showing the arrangement of a ball and a yoke in the housing of a lens driving device according to the second modified example.

[0042] Fig. 16 is an exploded perspective view of a camera device according to the present embodiment.

[0043] Fig. 17 is a perspective view of an optical device according to the present embodiment.

[0044] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0045] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0046] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which the present invention belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0047] Additionally, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0048] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0049] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components, and are not intended to limit the nature, order, or sequence of the components.

[0050] And, when a component is described as being 'connected', 'coupled', or 'connected' to another component, it may include not only cases where the component is 'connected', 'coupled', or 'connected' directly to the other component, but also cases where the component is 'connected', 'coupled', or 'connected' by another component between the component and the other component.

[0051] Additionally, when described as being formed or arranged "above" or "below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below," the meaning may include not only the upward direction but also the downward direction based on one component.

[0052] The 'optical axis direction (see OA in Fig. 4)' used below is defined as the optical axis direction of the lens and / or image sensor coupled to the lens driving device.

[0053] The 'vertical direction' used below may be a direction parallel to or the same direction as the optical axis direction. The vertical direction may correspond to the 'z-axis direction'. The 'horizontal direction' used below may be a direction perpendicular to the vertical direction. That is, the horizontal direction may be a direction perpendicular to the optical axis. Therefore, the horizontal direction may include the 'x-axis direction' and the 'y-axis direction'.

[0054] The 'auto focus (AF) function' used below is defined as a function that automatically focuses on a subject by adjusting the distance from the image sensor by moving the lens in the optical axis direction according to the distance of the subject so that a clear image of the subject can be obtained on the image sensor. In addition, 'closed-loop auto focus (CLAF) control' is defined as a function that detects the distance between the image sensor and the lens and provides feedback control of the position of the lens in real time to improve the accuracy of focus adjustment.

[0055] Hereinafter, either the “x-axis direction” or the “y-axis direction” may be referred to as the “first direction” and the other may be referred to as the “second direction.”

[0056]

[0057] Below, the configuration of the lens driving device according to the present embodiment is described with reference to the drawings.

[0058] Fig. 1 is a perspective view of a lens driving device according to the present embodiment. Fig. 2 is a cross-sectional view taken along line AA of Fig. 1. Fig. 3 is an enlarged view of area B of Fig. 2. Fig. 4 is a cross-sectional view taken from above of the lens driving device according to the present embodiment, cut perpendicular to the optical axis. Fig. 5 is an exploded perspective view of the lens driving device according to the present embodiment. Fig. 6 is a perspective view of the lens driving device according to the present embodiment with the cover member omitted. Fig. 7 is a perspective view showing a housing and related components of the lens driving device according to the present embodiment. Fig. 8 is a cross-sectional view showing a state in which a ball and a yoke are arranged in the housing of the lens driving device according to the present embodiment. Fig. 9 is an exploded perspective view of the housing and substrate of the lens driving device according to the present embodiment. Fig. 10 is a perspective view showing a lens holder and related components of the lens driving device according to the present embodiment. Fig. 11 is a bottom perspective view of the lens holder and related components of the lens driving device according to the present embodiment, viewed from a different direction than Fig. 10. Fig. 12 (a) is a cross-sectional view showing an initial state in which no current is applied to the coil of the lens driving device according to the present embodiment, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke.

[0059] The lens driving device (10) of the present embodiment may include an AF structure in which an AF moving part (200) and a fixed part (100) are brought into close contact with each other by the attractive force between a yoke (500) and a magnet (310) and a plurality of balls (400) are positioned therebetween. A lens holder (210) may be positioned inside the AF driving part (300). The lens holder (210) may be driven in the optical axis direction by a driving magnet (310) and a coil (320) facing it, and a focusing function may be performed.

[0060] The lens driving device (10) may include a fixed part (100). The fixed part (100) may be a part that is relatively fixed when the moving part (200) moves. The fixed part (100) may be a part that is fixed when the auto focus is driven. The fixed part (100) may correspond to the image sensor (60) side, and the moving part (200) may correspond to the lens side.

[0061] The lens actuator (10) may include a housing (110). The fixing member (100) may include the housing (110). The housing (110) may be a base. The housing (110) may accommodate a lens holder (210) therein. The housing (110) may be disposed on the outside of the lens holder (210). The housing (110) may be disposed below the lens holder (210). The housing (110) may be coupled to the cover member (120). The housing (110) may be disposed within the cover member (120). The housing (110) may be disposed below the cover member (120).

[0062] The housing (110) may include a step portion. The step portion may be formed at the lower end of the outer surface of the housing (110). The step portion may be formed by protruding the lower end of the outer surface of the housing (110). A side plate (122) of the cover member (120) may be placed at the step portion.

[0063] The housing (110) may include a lower plate (111). The lower plate (111) may be arranged perpendicular to the optical axis. The housing (110) may include a side wall (112). The side wall (112) may be formed on an outer edge of the lower plate (111). The side wall (112) may be arranged parallel to the optical axis. The side wall (112) may include a plurality of side walls. The side wall (112) may include four side walls. The side wall (112) may include a first side wall and a second side wall arranged opposite to each other, and a third side wall and a fourth side wall arranged opposite to each other.

[0064] The housing (110) may include a support (113). The support (113) may be formed to protrude upward from the lower plate (111). The support (113) may be disposed within the side wall (112). The support (113) may be disposed parallel to the optical axis. A yoke (500) may be disposed on the support (113). A ball (400) may be disposed on the support (113). The support (113) may be inserted into a lens holder (210). The support (113) may be disposed in a hole penetrating the lens holder (210) in the optical axis direction.

[0065] The housing (110) may include a groove (113-1). The groove (113-1) may be a ball rail. A ball (400) may be arranged in the groove (113-1). The groove (113-1) may be arranged in the optical axis direction. The groove (113-1) may extend in the optical axis direction. The ball (400) may come into contact with the groove (113-1). The ball (400) may move along the groove (113-1).

[0066] The lens actuator (10) may include a cover member (120). The fixing member (100) may include the cover member (120). The cover member (120) may be a cover. The cover member (120) may be a cover can. The cover member (120) may be placed in the housing (110). The cover member (120) may be placed on the housing (110). The cover member (120) may be fixed to the housing (110). The cover member (120) may be coupled to the housing (110). The cover member (120) may be adhesively bonded to the housing (110). The cover member (120) may accommodate at least a portion of the housing (110) therein. The cover member (120) may be a shield can. The cover member (120) may be formed of metal.

[0067] The cover member (120) may include a top plate (121). The top plate (121) may include a hole through which light passes. The top plate (121) may include a hole formed at a position corresponding to a lens. The cover member (120) may include a side plate (122). The side plate (122) may extend from the top plate (121). The side plate (122) may extend downward from an outer edge of the top plate (121). The side plate (122) may be formed in a shape bent from the top plate (121).

[0068] The side plate (122) of the cover member (120) may include a plurality of side plates. The side plate (122) may include a first side plate and a second side plate arranged opposite each other, and a third side plate and a fourth side plate arranged opposite each other.

[0069] The lens actuator (10) may include a substrate (130). The fixing member (100) may include the substrate (130). The substrate (130) may be disposed in the housing (110). The substrate (130) may be disposed on the housing (110). The substrate (130) may be fixed to the housing (110). The substrate (130) may be coupled to the housing (110). The substrate (130) may be adhered to the housing (110). The substrate (130) may be disposed on the side plate (122) of the cover member (120). The substrate (130) may be fixed to the side plate (122) of the cover member (120). The substrate (130) can be coupled to the side plate (122) of the cover member (120). The substrate (130) can be adhered to the side plate (122) of the cover member (120). The substrate (130) can be a flexible printed circuit board (FPCB). The substrate (130) can supply power to the coil (320). The substrate (130) can supply power to the sensor (330). The substrate (130) can be arranged parallel to the optical axis.

[0070] The substrate (130) may include a terminal. The terminal may be arranged on the outer surface of the substrate (130). The terminal may be formed on the bottom of the substrate (130). The terminal may include a plurality of terminals. The terminal may be coupled to a terminal of the printed circuit board (50). The terminal may include a terminal electrically connected to the sensor (330). The terminal may include a terminal electrically connected to the coil (320).

[0071] The lens driving device (10) may include a moving part (200). The moving part (200) may be a part that moves with respect to the fixed part (100). The moving part (200) may be moved by the driving part (300). The moving part (200) may be arranged to be movable with respect to the fixed part (100). The moving part (200) may move with respect to the fixed part (100) when autofocus is driven.

[0072] The lens actuator (10) may include a lens holder (210). The moving unit (200) may include the lens holder (210). The lens holder (210) may be a carrier. The lens holder (210) may be placed in the housing (110). The lens holder (210) may be placed on the housing (110). The lens holder (210) may be placed within the housing (110). The lens holder (210) may be movably placed in the housing (110). The lens holder (210) may move with respect to the housing (110). The lens holder (210) may move in the optical axis direction. The lens holder (210) may be coupled with the lens. The lens holder (210) may move integrally with the lens.

[0073] The lens holder (210) may include side walls. The lens holder (210) may include a plurality of side walls. The lens holder (210) may include four side walls. The lens holder (210) may include first to fourth side walls.

[0074] The lens holder (210) may include a first side wall (211). A magnet (310) may be arranged on the first side wall (211). The magnet (310) may be arranged on the outer surface of the first side wall (211). A ball (400) may be arranged on the first side wall (211). A ball (400) may be arranged on the inner surface of the first side wall (211).

[0075] The lens holder (210) may include a groove (211-1). The groove (211-1) may be a magnet receiving groove. The groove (211-1) may be formed by being recessed into the outer surface of the first side wall (211) of the lens holder (210). A magnet (310) may be placed in the groove (211-1). At least a portion of the magnet (310) may be received in the groove (211-1).

[0076] The lens holder (210) may include a groove (211-2). The groove (211-2) may be a ball receiving groove. The groove (211-2) may be formed by being recessed into the inner surface of the first side wall (211) of the lens holder (210). A ball (400) may be placed in the groove (211-2). At least a portion of the ball (400) may be received in the groove (211-2).

[0077] Hereinafter, one of ‘Home (211-1)’ and ‘Home (211-2)’ may be referred to as ‘Home 1’ and the other as ‘Home 2’.

[0078] The lens holder (210) may include an upper stopper (212). The upper stopper (212) may be formed on an upper surface of the lens holder (210). The upper stopper (212) may be formed on an upper surface of the first side wall (211). The upper stopper (212) may form an upper end of the lens holder (210). The upper stopper (212) may come into contact with the upper plate (121) of the cover member (120) when the lens holder (210) moves upward. That is, the upward movement of the lens holder (210) may be restricted by the upper stopper (212). The upper stopper (212) may include a protrusion.

[0079] The lens holder (210) may include a lower stopper (213). The lower stopper (213) may be formed on a lower surface of the lens holder (210). The lower stopper (213) may be formed on a lower surface of the first side wall (211). The lower stopper (213) may form a lower end of the lens holder (210). The lower stopper (213) may come into contact with the housing (110) when the lens holder (210) moves downward. That is, the downward movement of the lens holder (210) may be restricted by the lower stopper (213). The lower stopper (213) may include a protrusion.

[0080] The lens driving device (10) may include a driving unit (300). The driving unit (300) may move the moving unit (200) relative to the fixed unit (100). When power is applied to the driving unit (300), the moving unit (200) may move. The driving unit (300) may include a magnet (310) and a coil (320). The driving unit (300) may move the moving unit (200) through electromagnetic interaction. The magnet (310) and the coil (320) may move the lens holder (210) relative to the housing (110). The magnet (310) and the coil (320) may move the lens holder (210) in the optical axis direction.

[0081] The lens driving device (10) may include a magnet (310). The driving unit (300) may include a magnet (310). The magnet (310) may be placed on the lens holder (210). The magnet (310) may be placed on the lens holder (210). The magnet (310) may be fixed to the lens holder (210). The magnet (310) may be coupled to the lens holder (210). The magnet (310) may be bonded to the lens holder (210) with an adhesive.

[0082] The magnet (310) can be positioned corresponding to the coil (320). The magnet (310) can overlap the coil (320) in a direction perpendicular to the optical axis. The magnet (310) can overlap the coil (320) in the x-axis direction. The magnet (310) can be positioned to face the coil (320). The magnet (310) can face the coil (320). The magnet (310) can interact with the coil (320). The magnet (310) can electromagnetically interact with the coil (320). The magnet (310) can move when current is applied to the coil (320). The magnet (310) can move integrally with the lens holder (210).

[0083] The magnet (310) may be a four-pole magnet. The magnet (310) may include a first magnet portion including a north pole and a south pole, a second magnet portion disposed on the first magnet portion and including a south pole and a north pole, and a neutral portion disposed between the first magnet portion and the second magnet portion. The magnet (310) may be disposed in the optical axis direction.

[0084] Alternatively, the magnet (310) may be a two-pole magnet. For example, the upper region of the magnet (310) may be the N pole and the lower region may be the S pole.

[0085] The magnet (310) may be positioned so that it interacts with the yoke (500). The ball (400) may be pressed between the lens holder (210) and the housing (110) by the force exerted by the magnet (310) toward the yoke (500). Through this, the ball (400) may be maintained in close contact with the lens holder (210) and the housing (110).

[0086] In a direction perpendicular to the optical axis, the magnet (310) may be placed between the yoke (500) and the coil (320). In a direction perpendicular to the optical axis, at least a portion of the magnet (310) may be placed between the yoke (500) and the coil (320). In a direction perpendicular to the optical axis, the magnet (310) may overlap the yoke (500) and the coil (320).

[0087] The lens driving device (10) may include a coil (320). The driving unit (300) may include the coil (320). The coil (320) may be disposed on the substrate (130). The coil (320) may be fixed to the substrate (130). The coil (320) may be coupled to the substrate (130). The coil (320) may be soldered to the substrate (130). The coil (320) may be disposed on the housing (110). The coil (320) may be fixed to the housing (110). The coil (320) may be disposed on the side plate (122) of the cover member (120). The coil (320) can be placed on the side plate (122) of the cover member (120).

[0088] The coil (320) can interact with the magnet (310). The coil (320) can be positioned to face the magnet (310). The coil (320) can face the magnet (310). The coil (320) can be positioned at a position corresponding to the magnet (310). The coil (320) can overlap the magnet (310) in a direction perpendicular to the optical axis. The coil (320) can overlap the magnet (310) in the x-axis direction. The coil (320) can move the magnet (310). The coil (320) can move the lens holder (210). The coil (320) can move the lens.

[0089] When current is applied to the coil (320), the magnet (310) can move. When a forward current is applied to the coil (320), the magnet (310) can move upward. When a reverse current is applied to the coil (320), the magnet (310) can move downward. However, conversely, when a reverse current is applied to the coil (320), the magnet (310) can move upward, and when a forward current is applied to the coil (320), the magnet (310) can move downward.

[0090] The lens driving device (10) may include a sensor (330). The driving unit (300) may include the sensor (330). The sensor (330) may be disposed on the substrate (130). The sensor (330) may be disposed on the substrate (130). The sensor (330) may be coupled to the substrate (130). The sensor (330) may be soldered to the substrate (130).

[0091] The sensor (330) can detect the magnet (310). The sensor (330) can detect the magnetic force of the magnet (310). The sensor (330) may be a Hall sensor. The sensor (330) can detect the position or movement of the magnet (310). Through this, the sensor (330) can detect the position or movement of the lens holder (210). The sensor (330) can detect the lens holder (210). The position of the magnet (310) detected by the sensor (330) can be used for autofocus feedback control.

[0092] The lens actuator (10) may include a guide unit. The guide unit may guide the movement of the moving unit (200) relative to the fixed unit (100). The guide unit may guide the movement of the moving unit (200) in the optical axis direction.

[0093] The lens actuator (10) may include a ball (400). The guide portion may include the ball (400). The ball (400) may be formed of ceramic. The ball (400) may be a ceramic ball. The ball (400) may be formed in a spherical shape. The ball (400) may include a curved surface.

[0094] The ball (400) can be placed in the housing (110). The ball (400) can be placed on the housing (110). The ball (400) can be in contact with the housing (110). The ball (400) can be placed in the groove (113-1) of the housing (110). The ball (400) can be placed on the groove (113-1) of the housing (110). The ball (400) can be in contact with the groove (113-1) of the housing (110).

[0095] The ball (400) can be placed in the lens holder (210). The ball (400) can be placed on the lens holder (210). The ball (400) can be in contact with the lens holder (210). The ball (400) can be placed in the groove (211-2) of the lens holder (210). The ball (400) can be placed on the groove (211-2) of the lens holder (210). The ball (400) can be in contact with the groove (211-2) of the lens holder (210).

[0096] The ball (400) can be placed between the housing (110) and the lens holder (210). The ball (400) can be placed between the groove (113-1) of the housing (110) and the groove (211-2) of the lens holder (210). The ball (400) can be placed between the housing (110) and the lens holder (210) in a first direction perpendicular to the optical axis direction. The ball (400) can be placed between the lens holder (210) and the housing (110) in a direction in which the magnet (310) faces the yoke (500).

[0097] The ball (400) can move in the direction of the optical axis. The ball (400) can move together with the lens holder (210) when the lens holder (210) moves. The ball (400) can limit the movement of the lens holder (210) to the direction of the optical axis. The lens holder (210) can be limited by the ball (400) from moving in any direction other than the direction of the optical axis. The ball (400) can guide the movement of the lens holder (210) in the direction of the optical axis. The ball (400) can rotate in place when the lens holder (210) moves.

[0098] The magnet (310) may include an outer surface facing the coil (320) and an inner surface opposite the outer surface. The shortest distance between the ball (400) and the inner surface of the magnet (310) may be shorter than the shortest distance between the ball (400) and the outer surface of the magnet (310). That is, the ball (400) may be arranged closer to the inner surface than to the outer surface of the magnet (310).

[0099] The shortest distance between the ball (400) and the yoke (500) may be shorter than the shortest distance between the ball (400) and the magnet (310). That is, the ball (400) may be arranged closer to the yoke (500) than to the magnet (310). In this embodiment, the ball (400) may be arranged on the inner side compared to the comparative example. At this time, in the comparative example, the ball (400) may be arranged on the outer surface of the lens holder (210). In this embodiment, since the ball (400) is arranged further inward compared to the comparative example, even if a moment occurs in the lens holder (210) with respect to the ball (400), the influence thereof may be reduced compared to the comparative example.

[0100] The ball (400) may include a plurality of balls. The ball (400) may include a plurality of balls that overlap in the optical axis direction. The ball (400) may include a first ball (401) and a fourth ball (404) that overlap each other in the optical axis direction. The ball (400) may include a second ball (402) and a third ball (403) that are arranged between the first ball (401) and the fourth ball (404) and have a smaller diameter than the first ball (401) and the fourth ball (404). However, the second ball (402) and the third ball (403) only maintain the distance between the first ball (401) and the fourth ball (404) and do not guide the movement of the lens holder (210), so they can be understood as separate components from the ball (400). Alternatively, the second ball (402) and the third ball (403) may also assist in the movement of the lens holder (210). The second ball (402) and the third ball (403) may be spaced apart from the housing (110). The second ball (402) and the third ball (403) may be spaced apart from the lens holder (210).

[0101] The second ball (402) and the third ball (403) can maintain a gap between the first ball (401) and the fourth ball (404). The diameters of the second ball (402) and the third ball (403) may be smaller than the diameters of the first ball (401) and the fourth ball (404). The first ball (401) and the fourth ball (404) may be main balls, and the second ball (402) and the third ball (403) may be support balls. The support balls may be used to secure space for the main ball. However, the support balls may also participate in the rolling of the moving part (200).

[0102] The lens actuator (10) may include a ball pressurizing member. The ball pressurizing member may pressurize the ball so that the ball remains in contact with the surface. The ball pressurizing member may include a magnet and a yoke that exert an attractive force on each other.

[0103] The lens actuator (10) may include a yoke (500). The ball pressurizing member may include the yoke (500). The yoke (500) may be disposed in the housing (110). The yoke (500) may be disposed on the housing (110). The yoke (500) may be fixed to the housing (110). The yoke (500) may be coupled to the housing (110). The yoke (500) may be adhesively bonded to the housing (110). The yoke (500) may be disposed in a groove formed in the support (113) of the housing (110).

[0104] The yoke (500) can exert an attractive force on the magnet (310). A force can be applied to the magnet (310) to move it toward the yoke (500). The lens holder (210) can press the ball (400) toward the housing (110) by the attractive force between the magnet (310) and the yoke (500).

[0105] The shortest distance between the yoke (500) and the optical axis may be shorter than the shortest distance between the magnet (310) and the optical axis. That is, the yoke (500) may be positioned closer to the optical axis than the magnet (310). The yoke (500) may be positioned inward of the magnet (310). Through this, a force may be applied to the magnet (310) to move inward, i.e., in the direction of the optical axis.

[0106] The magnet (310) may include an outer surface facing the coil (320). The ball (400) may overlap the yoke (500) in a first direction that is perpendicular to the optical axis and parallel to the outer surface of the magnet (310). The ball (400) may overlap the coil (320) in a second direction that is perpendicular to the optical axis and perpendicular to the outer surface of the magnet (310). The first direction and the second direction may be perpendicular.

[0107] The magnet (310) may include a first portion that overlaps the ball (400) in a first direction and a second portion that does not overlap the ball (400) in the first direction. When viewed from above, the magnet (310) may include a first portion that overlaps the ball (400) in the first direction and a second portion that does not overlap the ball (400) in the first direction. However, as a variation, all portions of the magnet (310) may overlap the ball (400) when viewed from above. Or, as another variation, not all portions of the magnet (310) may overlap the ball (400) when viewed from above.

[0108] The yoke (500) may include a plurality of yokes. The yoke (500) may include two yokes. The yoke (500) may include two yokes of corresponding shapes. The yoke (500) may include two yokes of the same shape. The two yokes may be arranged symmetrically with respect to an imaginary plane including the optical axis.

[0109] The yoke (500) may include a first yoke (501) and a second yoke (502) that are spaced apart from each other. The first yoke (501) may include a first portion (500-1) and a second portion (500-2) that protrudes inwardly from the first portion (500-1). The second portion (500-2) of the first yoke (501) may protrude in a direction from the first portion (500-1) toward the second yoke (502). The second yoke (502) may include a first portion (500-1) and a second portion (500-2) that protrudes inwardly from the first portion (500-1). The second portion (500-2) of the second yoke (502) may protrude in a direction from the first portion (500-1) toward the first yoke (501). In the optical axis direction, the length of the first part (500-1) may be longer than the length of the second part (500-2).

[0110] In this embodiment, the process sequence for assembling the lens actuator (10) may be roughly as follows. First, the housing (110), the substrate (130), and the yoke (500) may be assembled to form a housing assembly. Then, the lens holder (210) and the magnet (310) may be assembled to form a lens holder assembly. Afterwards, the housing assembly and the lens holder assembly may be assembled, and the cover member may be assembled.

[0111] In the present embodiment, the return force acting on the magnet (310) can be minimized through the structure of the T-shaped rotation of the yoke (500). At this time, the return force may be a force that causes the magnet (310) to return to its original position. In the present embodiment, the force that causes the magnet (310) to return to its initial position may not be applied or may be close to 0. Through this, the amount of current consumed to drive the moving part (200) in the present embodiment can be minimized. That is, in the present embodiment, the current consumption generated during AF driving can be reduced compared to the first modified example.

[0112]

[0113] Below, the configuration of the lens driving device according to the first modified example is described with reference to the drawings.

[0114] Fig. 13 (a) is a cross-sectional view showing an initial state in which no current is applied to the coil of the lens driving device according to the first modified example, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke.

[0115] In the first variant, the yoke (500a) may be in the shape of a square plate, as illustrated in (b) of Fig. 13. The yoke (500a) may be arranged parallel to the optical axis. In the first variant, a return force may be generated between the magnet (310) and the yoke (500a). A continuous force may be applied to the magnet (310) in a direction such that the center of the magnet (310) and the center of the yoke (500a) coincide.

[0116]

[0117] Below, the configuration of the lens driving device according to the second modified example is described with reference to the drawings.

[0118] Fig. 14 (a) is a cross-sectional view showing the initial state in which no current is applied to the coil of the lens driving device according to the second modified example, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke. Fig. 15 is a cross-sectional view showing the arrangement of the ball and the yoke in the housing of the lens driving device according to the second modified example.

[0119] In the second modified example, the yoke (500b) may include a first part (500b-1) and a second part (500b-2) that are arranged long in the optical axis direction, and a third part (500b-3) that connects the lower end of the first part (500b-1) and the lower end of the second part (500b-2). The upper end of the first part (500b-1) and the upper end of the second part (500b-2) may not be connected to each other.

[0120] In the second variation, the third part (500b-3) can overlap the magnet (310) in a direction perpendicular to the optical axis when the moving part (200) is placed at the bottom.

[0121] In the second modified example, a pre-load may be applied to the magnet (310) by the attractive force between the magnet (310) and the yoke (500b), particularly by the attractive force between the magnet (310) and the third part (500b-3) of the yoke (500b). At this time, the pre-load may be a force that moves the magnet (310) from an initial position where no current is applied to the coil (320) to a specific position. In the second modified example, the magnet (310) may be moved by the attractive force with the third part (500b-3) of the yoke (500b) from an initial position where no current is applied to the coil (320) so that the lens holder (210) comes into contact with the lower plate (111) of the housing (110). That is, in the second modified example, the lens holder (210) can be maintained in contact with the lower plate (111) of the housing (110) at the initial position where no current is applied to the coil (320). Therefore, even when an external force is generated in the initial state, noise generated by the lens holder (210) hitting the housing (110) or the cover member (120) can be prevented. That is, the second modified example can be an improved structure in terms of preventing impact noise compared to the first modified example.

[0122]

[0123] Below, the auto focus operation of the lens driving device according to the present embodiment is described with reference to the drawings.

[0124] Fig. 12 (a) is a cross-sectional view showing an initial state in which no current is applied to the coil of the lens driving device according to the present embodiment, and (b) is a perspective view showing the arrangement structure of the driving unit and the yoke.

[0125] When current is applied to the coil (320), an electromagnetic field is formed around the coil (320), and the coil (320) and the magnet (310) can electromagnetically interact. At this time, since the coil (320) is fixed to the substrate (130) and the housing (110), the magnet (310) can move. The magnet (310) can move together with the lens holder (210) and the lens. At this time, the ball (400) guides the movement of the lens holder (210) with respect to the housing (110) in the optical axis direction, so that the lens holder (210) and the lens can move in the optical axis direction (see OA of FIG. 4). Through this, the lens can move in the optical axis direction with respect to the image sensor (60).

[0126] In more detail, when a forward current is applied to the coil (320), the magnet (310) can move upward in the optical axis direction due to the interaction between the coil (320) and the magnet (310). Through this, the lens can move away from the image sensor (60). In the initial position where no current is applied to the coil (320), an upper stroke space (see a of (a) of FIG. 12) can be formed between the upper stopper (212) of the lens holder (210) and the upper plate (121) of the cover member (120). When a forward current is applied to the coil (320), the lens holder (210) can move within the upper stroke space.

[0127] In addition, when a reverse current is applied to the coil (320), the magnet (310) can move downward in the optical axis direction due to the interaction between the coil (320) and the magnet (310). Through this, the lens can come closer to the image sensor (60). In the initial position where no current is applied to the coil (320), a lower stroke space (see b of (a) of FIG. 12) can be formed between the lower stopper (213) of the lens holder (210) and the lower plate (111) of the housing (110). When a reverse current is applied to the coil (320), the lens holder (210) can move within the lower stroke space.

[0128] In this way, by applying a forward or reverse current to the coil (320), the image of the subject formed on the image sensor (60) can be clearly adjusted. That is, auto focus operation can be performed.

[0129] Furthermore, the sensor (330) can detect the magnetic field of the magnet (310) in real time to detect the positions of the magnet (310), the lens holder (210), and the lens. Feedback control can be performed to move the lens to a more accurate position through the position of the lens detected by the sensor (330). In the present embodiment, more precise autofocus operation can be performed through autofocus feedback control.

[0130] In the present embodiment and the first modified example, the pre-load that guides the initial position of the magnet (310) between the yoke (500, 500a) and the magnet (310) may not work or may be weak. Therefore, the auto focus operation may be operated in the same manner as in the present embodiment in the first modified example. The auto focus operation of the lens driving device according to the first modified example may be analogously applied to the description of the auto focus operation of the lens driving device according to the present embodiment.

[0131] However, in the second modified example, a pre-load may act between the yoke (500b) and the magnet (310) to guide the initial position of the magnet (310). Accordingly, the lens holder (210) may be in contact with the lower plate (111) of the housing (110) at the initial position where no current is applied to the coil (320). In this case, only an upper stroke space (see a of (a) of FIG. 14) may be formed between the upper stopper (212) of the lens holder (210) and the upper plate (121) of the cover member (120) at the initial position where no current is applied to the coil (320), and a lower stroke space may not be formed.

[0132] In the second variation, when a positive current is applied to the coil (320), the magnet (310) can move upward in the optical axis direction due to the interaction between the coil (320) and the magnet (310). Through this, the lens can move away from the image sensor (60). When a positive current is applied to the coil (320), the lens holder (210) can move within the upper stroke space (see a of (a) of FIG. 14).

[0133]

[0134] Below, the configuration of the camera device according to the present embodiment is described with reference to the drawings.

[0135] Fig. 16 is an exploded perspective view of a camera device according to the present embodiment.

[0136] The camera device (10A) may include a lens driving device (10). The lens driving device (10) may be a voice coil motor (VCM). The lens driving device (10) may be a lens driving motor. The lens driving device (10) may be a lens driving actuator. The lens driving device (10) may include an AF module. As a variation, the lens driving device (10) may include an OIS module. The lens driving device (10) may be a device that drives a lens. As illustrated in the drawing, the lens driving device (10) may include a lens. However, the lens may be understood as a separate component from the lens driving device (10) as a component of the camera device (10A).

[0137] The camera device (10A) may include a lens module (20). The lens module (20) may be disposed on an image sensor (60). The lens module (20) may be coupled to a lens driving device (10). The lens module (20) may be coupled to a lens holder (210) of the lens driving device (10). The lens module (20) may be moved integrally with the lens holder (210). The lens module (20) may be disposed to be movable with respect to the image sensor (60). The lens module (20) may be moved in the optical axis direction with respect to the image sensor (60).

[0138] The lens module (20) may include a lens. The lens may include a plurality of lenses. The lens module (20) may include a barrel. The plurality of lenses may be arranged within the barrel. The plurality of lenses may be coupled to the inner surface of the barrel. The plurality of lenses may be arranged in a stacked manner within the barrel.

[0139] The camera device (10A) may include a filter (30). The filter (30) may block light of a specific frequency band from passing through the lens module (20) from being incident on the image sensor (60). The filter (30) may be arranged parallel to the xy plane. The filter (30) may be arranged between the lens module (20) and the image sensor (60). The filter (30) may be arranged on the sensor base (40). Alternatively, the filter (30) may be arranged on the housing (110) of the lens driving device (10). The filter (30) may include an infrared filter. The infrared filter may block light in the infrared region from being incident on the image sensor (60).

[0140] The camera device (10A) may include a sensor base (40). The sensor base (40) may be disposed between the lens actuator (10) and the printed circuit board (50). The sensor base (40) may include a protrusion (41) on the inside of which a filter (30) is disposed. An opening may be formed in the portion of the sensor base (40) where the filter (30) is disposed so that light passing through the filter (30) may be incident on the image sensor (60). The adhesive member may couple or adhere the housing (110) of the lens actuator (10) to the sensor base (40). The adhesive member may additionally serve to prevent foreign substances from entering the interior of the lens actuator (10). The adhesive member may include at least one of an epoxy, a thermosetting adhesive, and an ultraviolet-curable adhesive.

[0141] The camera device (10A) may include a printed circuit board (PCB) (50). The printed circuit board (50) may be a substrate or a circuit board. A lens driving device (10) may be disposed on the printed circuit board (50). A sensor base (40) may be disposed between the printed circuit board (50) and the lens driving device (10). The printed circuit board (50) may be electrically connected to the lens driving device (10). An image sensor (60) may be disposed on the printed circuit board (50). Various circuits, components, control units, etc. may be provided on the printed circuit board (50) to convert an image formed on the image sensor (60) into an electrical signal and transmit it to an external device.

[0142] The camera device (10A) may include an image sensor (60). The image sensor (60) may be configured to form an image by incident light passing through a lens and a filter (30). The image sensor (60) may be mounted on a printed circuit board (50). The image sensor (60) may be electrically connected to the printed circuit board (50). For example, the image sensor (60) may be coupled to the printed circuit board (50) using surface mounting technology (SMT). As another example, the image sensor (60) may be coupled to the printed circuit board (50) using flip chip technology. The image sensor (60) may be arranged such that its optical axis is aligned with that of the lens. That is, the optical axis of the image sensor (60) and the optical axis of the lens may be aligned. The image sensor (60) can convert light irradiated onto the effective image area of ​​the image sensor (60) into an electrical signal. The image sensor (60) can be any one of a CCD (charge coupled device), a MOS (metal oxide semi-conductor), a CPD, and a CID.

[0143] The camera device (10A) may include a motion sensor (70). The motion sensor (70) may be mounted on a printed circuit board (50). The motion sensor (70) may be electrically connected to a control unit (80) through a circuit pattern provided on the printed circuit board (50). The motion sensor (70) may output rotational angular velocity information due to the movement of the camera device (10A). The motion sensor (70) may include a two-axis or three-axis gyro sensor or an angular velocity sensor.

[0144] The camera device (10A) may include a control unit (80). The control unit (80) may be disposed on a printed circuit board (50). The control unit (80) may be electrically connected to a coil (320) of a lens driving device (10). The control unit (80) may individually control the direction, intensity, amplitude, etc. of the current supplied to the coil (320). The control unit (80) may control the lens driving device (10) to perform an autofocus function and / or a shake correction function. Furthermore, the control unit (80) may perform autofocus feedback control and / or shake correction feedback control for the lens driving device (10).

[0145] The camera device (10A) may include a connector (90). The connector (90) may be electrically connected to a printed circuit board (50). The connector (90) may include a port for electrically connecting to an external device.

[0146]

[0147] Below, the configuration of the optical device according to the present embodiment is described with reference to the drawings.

[0148] Fig. 17 is a perspective view of an optical device according to the present embodiment.

[0149] The optical device (1) may include one or more of a mobile phone, a cell phone, a portable terminal, a mobile terminal, a smart phone, a smart pad, a portable smart device, a digital camera, a laptop computer, a digital broadcasting terminal, a PDA (Personal Digital Assistant), a PMP (Portable Multimedia Player), and a navigation device. The optical device (1) may include any device for taking images or photographs.

[0150] An optical device (1) may include a main body (2). The optical device (1) may include a camera device (10A). The camera device (10A) may be disposed on the main body (2). The camera device (10A) may photograph a subject. The optical device (1) may include a display. The display may be disposed on the main body (2). The display may output one or more of a video or image captured by the camera device (10A). The display may be disposed on a first surface of the main body (2). The camera device (10A) may be disposed on one or more of the first surface of the main body (2) and a second surface opposite the first surface. The camera device (10A) may have a triple camera disposed in a vertical direction. Alternatively, the camera device (10A) may have a triple camera disposed in a horizontal direction.

[0151]

[0152] Although the embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical concept or essential features thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

Claims

1. Housing; A lens holder disposed on the housing; A magnet placed on the above lens holder; A coil interacting with the above magnet; a ball disposed between the housing and the lens holder; and A yoke disposed in the above housing and having a magnet and a force acting thereon, A lens driving device in which the shortest distance between the yoke and the optical axis is shorter than the shortest distance between the magnet and the optical axis.

2. In paragraph 1, A lens actuator that presses the ball toward the housing by the force of attraction between the magnet and the yoke.

3. In paragraph 1, The magnet includes an outer surface facing the coil and an inner surface opposite the outer surface, A lens actuator in which the shortest distance between the inner surface of the ball and the magnet is shorter than the shortest distance between the outer surface of the ball and the magnet.

4. In paragraph 1, A lens actuator in which the shortest distance between the ball and the yoke is shorter than the shortest distance between the ball and the magnet.

5. In paragraph 1, The magnet includes an outer surface facing the coil, A lens driving device in which the ball overlaps the yoke in a first direction that is perpendicular to the optical axis and parallel to the outer surface of the magnet.

6. In paragraph 5, A lens driving device in which the magnet includes a first portion that overlaps the ball in the first direction and a second portion that does not overlap the ball in the first direction.

7. In paragraph 1, The magnet includes an outer surface facing the coil, A lens driving device in which the ball overlaps the coil in a second direction that is perpendicular to the optical axis and perpendicular to the outer surface of the magnet.

8. In paragraph 1, A lens driving device in which the magnet is positioned between the yoke and the coil in a direction perpendicular to the optical axis.

9. In paragraph 1, The above magnet and the above coil move the lens holder in the optical axis direction, The above ball is a lens driving device including a plurality of balls overlapping in the optical axis direction.

10. In paragraph 1, The above lens holder includes a first side wall, A lens actuator including a first groove formed in a recessed shape on the outer surface of the first side wall and in which the magnet is placed, and a second groove formed in a recessed shape on the inner surface of the first side wall and in which the ball is placed.

Images