Camera actuator

Abstract

A camera actuator according to an embodiment of the present invention comprises: a housing; a first lens assembly disposed on the housing; a second lens assembly and a third lens assembly moving in a first direction parallel to an optical axis in the housing; a driving module for moving the second lens assembly and the third lens assembly in the first direction; and a control unit for controlling the driving module. The control unit moves at least one of the second lens assembly or the third lens assembly by repeating a first section for setting a first gain in the driving module and a second section for setting a second gain in the driving module at least once. In a moving section in which at least one of the second lens assembly or the third lens assembly is moved in the first direction, the first section is relatively adjacent to an initial position of the moving section, and the second section is relatively adjacent to an arrival position of the moving section.

Description

Camera actuator

[0001] The present invention relates to a camera actuator.

[0002] A camera is a device that captures a subject in photos or videos, and it is mounted on portable devices, drones, vehicles, etc.

[0003] A camera device or camera module may have an Image Stabilization (IS) function that corrects or prevents shaking caused by user movement to improve image quality, an Auto Focusing (AF) function that automatically adjusts the distance between the image sensor and the lens to align the focal length of the lens, and a zooming function that increases or decreases the magnification of a distant subject through a zoom lens to take a picture.

[0004] Generally, in the case of autofocus (AF), the lens assembly continuously adjusts its position, whereas zooming has a movement range corresponding to the input magnification at the moment the user inputs the desired magnification.

[0005] However, when the input gain of the lens assembly performing the zooming function is high, there is a risk of collision during the movement process, and when the gain is low, there is a problem of a delay time occurring until zooming is completed.

[0006] The present invention is an invention devised to solve the problems of the aforementioned prior art, and aims to prevent the risk of collision resulting from the driving force of a lens assembly and driving.

[0007] The problems that the present invention aims to solve are not limited to those mentioned above, and other problems not mentioned herein will be clearly understood by those skilled in the art from the description below.

[0008] A camera actuator according to an embodiment of the present invention for achieving the above-described purpose comprises a housing, a first lens assembly disposed on the housing, a second lens assembly and a third lens assembly that move in a first direction parallel to an optical axis within the housing, a driving module that moves the second lens assembly and the third lens assembly in the first direction, and a control unit that controls the driving module. The control unit moves at least one of the second lens assembly or the third lens assembly by repeating at least once a first section for setting a first gain in the driving module and a second section for setting a second gain in the driving module. In the moving section in which at least one of the second lens assembly or the third lens assembly moves in the first direction, the first section is relatively adjacent to the initial position of the moving section, and the second section is relatively adjacent to the arrival position of the moving section.

[0009] According to the present embodiment, the second gain may be lower than the first gain.

[0010] According to the present embodiment, the second gain may be less than or equal to half of the first gain.

[0011] According to the present embodiment, the control unit can move only the second lens assembly by repeating the first section and the second section at least once through the driving module.

[0012] According to the present embodiment, the second lens assembly may be a zoom lens assembly, and the third lens assembly may be an AF (Auto Focus) lens assembly.

[0013] According to the present embodiment, when the control unit determines that the second lens assembly has reached the arrival position, it may set a third gain in the driving module and maintain the third gain during the period prior to the setting of the movement section.

[0014] According to the present embodiment, the third gain may be the same as either the first gain or the second gain.

[0015] According to the present embodiment, the third gain may be the same as the second gain of the second section relatively adjacent to the arrival position.

[0016] According to the present embodiment, the second section may be a section within a pre-set range based on the arrival location.

[0017] According to the present embodiment, the second section may be a section between the arrival location and the first section.

[0018] A camera actuator according to an embodiment of the present invention for solving the above problem may have the effect of preventing the driving force of a lens assembly and the risk of collision due to driving.

[0019] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims.

[0020] In addition, the effects of the present invention may be described in more detail in the detailed description of the present invention and are not necessarily limited to those presented above.

[0021] The summary described above, as well as the detailed description of the preferred embodiments of the present application described below, will be better understood when read in conjunction with the accompanying drawings.

[0022] Preferred embodiments are illustrated in the drawings for the purpose of illustrating the present invention.

[0023] However, it should be understood that the present application is not limited to the exact arrangement and means depicted.

[0024] FIG. 1 is a drawing illustrated for the overall explanation of a camera module according to an embodiment of the present invention;

[0025] FIG. 2 is a diagram showing an exploded view of a camera module according to an embodiment of the present invention;

[0026] FIG. 3 is a cross-sectional view of a camera module according to an embodiment of the present invention;

[0027] FIG. 4 is a drawing illustrated for the overall explanation of a camera actuator according to an embodiment of the present invention;

[0028] FIG. 5 is a drawing illustrating a situation in which a movement section of a camera actuator according to an embodiment of the present invention is input;

[0029] FIG. 6 is a drawing illustrating the arrival position of a camera actuator according to an embodiment of the present invention;

[0030] FIG. 7 is a drawing illustrating a change in gain in a state where the movement section of a camera actuator according to an embodiment of the present invention is input; and

[0031] FIG. 8 is a diagram illustrating the change in gain when the movement section of a camera actuator according to an embodiment of the present invention is input multiple times.

[0032] The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated and described in the drawings. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0033] Terms including ordinal numbers, such as second, first, etc., may be used to describe various components, but the components are not limited by the terms. The terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be named the first component, and similarly, the first component may be named the second component. The term "and / or" includes a combination of multiple related described items or any of the multiple related described items.

[0034] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0035] The terms used in this application are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "having" are intended to specify the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0036] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0037] Hereinafter, embodiments will be described in detail with reference to the attached drawings, provided that identical or corresponding components are given the same reference number regardless of the drawing symbols, and redundant descriptions thereof will be omitted.

[0038] Furthermore, in this specification, a camera actuator is a device that moves a lens, but is described as encompassing both concepts that include a lens and concepts that do not include a lens. Hereinafter, the first and second camera actuators are each described as concepts that include a lens. Additionally, a camera actuator that moves a lens may be referred to as a 'lens moving device' or a 'lens driving device'.

[0039] A preferred embodiment of the present invention, in which the objective of the present invention can be specifically realized, will be described below with reference to the attached FIGS. 1 to 8.

[0040] First, referring to FIGS. 1 and 2, a camera module (1000) according to an embodiment may consist of a cover (CV), a first camera actuator (A1), a second camera actuator (A2), and a circuit board (B). Here, the first camera actuator (A1) may be used as the first actuator, and the second camera actuator (A2) may be used as the second actuator.

[0041] The cover (CV) can cover the first camera actuator (A1) and the second camera actuator (A2). The coupling force between the first camera actuator (A1) and the second camera actuator (A2) can be improved by the cover (CV).

[0042] Furthermore, the cover (CV) may be made of a material that performs electromagnetic shielding. Accordingly, the first camera actuator (A1) and the second camera actuator (A2) inside the cover (CV) can be easily protected.

[0043] And the first camera actuator (A1) may be an OIS (Optical Image Stabilizer) actuator. For example, the first camera actuator (A1) can move an optical member in a direction perpendicular to the optical axis (axis of incident light).

[0044] The first camera actuator (A1) may include a fixed focal length lens disposed in a predetermined lens barrel (not shown). The fixed focal length lens may also be referred to as a "single focal length lens" or a "single lens."

[0045] The first camera actuator (A1) can change the path of light. In an embodiment, the first camera actuator (A1) can change the path of light vertically through an internal optical element (e.g., a prism or a mirror). For example, the optical element can change the light from a second direction to the direction of the optical axis. With this configuration, even if the thickness of the mobile terminal is reduced, a lens configuration larger than the thickness of the mobile terminal can be placed within the mobile terminal through the change of the light path, so that magnification, autofocus (AF), zoom, and OIS functions can be performed.

[0046] However, it is not limited to this, and the first camera actuator (A1) can change the light path multiple times vertically or at a predetermined angle.

[0047] The second camera actuator (A2) may be positioned at the rear end of the first camera actuator (A1). The second camera actuator (A2) may be coupled with the first camera actuator (A1). And the coupling between them may be achieved in various ways.

[0048] Additionally, the second camera actuator (A2) may be a zoom actuator or an AF (Auto Focus) actuator. For example, the second camera actuator (A2) may support one or more lenses and move the lenses according to a control signal from a predetermined control unit to perform an auto-focusing function or a zoom function.

[0049] And one or more lenses can move independently or individually along the optical axis.

[0050] The circuit board (B) may be positioned at the rear end of the second camera actuator (A2). The circuit board (B) may be electrically connected to the second camera actuator (A2) and the first camera actuator (A1). Additionally, there may be multiple circuit boards (B).

[0051] The camera module (1000) according to the embodiment may consist of a single or a plurality of camera modules (1000). For example, the plurality of camera modules may include a first camera module and a second camera module.

[0052] And a single camera module (1000) may include a single or multiple actuators. For example, a single camera module (1000) may include a first camera actuator (A1) and a second camera actuator (A2). Furthermore, the camera module (1000) may be used interchangeably with various terms such as camera device, imaging device, etc.

[0053] And the camera module (1000) is placed in a predetermined case (not shown) and may include an actuator (not shown) capable of driving a lens assembly. This will be explained in more detail through the drawings to be described later.

[0054] The actuator may be a voice coil motor, a micro actuator, a silicon actuator, etc., and may be applied in various ways such as electrostatic, thermal, bimorphic, and electrostatic force methods, but is not limited thereto. Additionally, in this specification, the camera actuator may be referred to as an actuator, etc. Furthermore, a camera module (1000) composed of a plurality of camera modules may be mounted in various electronic devices such as mobile terminals. Furthermore, the actuator may be a device that moves or tilts a lens or an optical element. However, below, the actuator is described as a concept that includes a lens or an optical element. Furthermore, the actuator may be referred to as a 'lens transfer device,' a 'lens moving device,' an 'optical element transfer device,' an 'optical element moving device,' etc.

[0055] Referring to FIG. 3, the camera module according to the embodiment may include a first camera actuator (A1) that performs an OIS function and a second camera actuator (A2) that performs a zooming function and an AF function.

[0056] Light can be incident into the camera module (1000) or the first camera actuator (A1) through an opening region located on the upper surface of the first camera actuator (A1). That is, light is incident into the interior of the first camera actuator (A1) along the optical axis direction, and the optical path can be changed vertically through an optical member. Then, light passes through the second camera actuator (A2) and can be incident on an image sensor (IS) located at one end of the second camera actuator (A2) (PATH).

[0057] Additionally, in this specification, the inner side may be the direction toward the first camera actuator (A1) from the cover (CV), and the outer side may be the opposite direction to the inner side. For example, the first camera actuator (A1) and the second camera actuator (A2) may be located on the inner side of the cover (CV), and the cover (CV) may be located on the outer side of the first camera actuator (A1) or the second camera actuator (A2).

[0058] The camera module (1000) according to the embodiment can improve the spatial limitations of the first camera actuator (A1) and the second camera actuator (A2) by changing the light path. The camera module (1000) according to the embodiment can expand the light path while minimizing the thickness of the camera module (1000) in response to the change in the light path. Furthermore, it should be understood that the second camera actuator (A2) may provide a high range of magnification by controlling the focus, etc., in the expanded light path.

[0059] In addition, the camera module (1000) according to the embodiment can implement OIS by controlling the optical path through the first camera actuator (A1), thereby minimizing the occurrence of decentering or tilt phenomena and producing optimal optical characteristics.

[0060] Furthermore, the second camera actuator (A2) may include an optical system and a lens driving unit. For example, at least one of the first lens assembly (200), the second lens assembly (300), and the third lens assembly (400) may be disposed in the second camera actuator (A2). This will be explained in more detail through the drawings to be described later.

[0061] Additionally, the second camera actuator (A2) is equipped with a coil and a magnet to perform high-magnification zooming and autofocus functions.

[0062] For example, the second lens assembly (300) and the third lens assembly (400) may be moving lenses that move via a coil, a magnet, and a guide pin, and the first lens assembly (200) may be a fixed lens, but is not limited thereto. For example, the first lens assembly (200) may perform the function of a focuser that forms an image of light at a specific location, and the distance to the subject or the image distance may change significantly depending on the movement of the second lens assembly (300), resulting in a state of large magnification change. Furthermore, the second lens assembly (300), which is a changeable lens, may play an important role in the change of focal length or magnification of the optical system. Meanwhile, the image formed by the second lens assembly (300), which is a changeable lens, may differ slightly depending on the location. Accordingly, the third lens assembly (400) may perform a position compensation function for the image formed by the changeable lens. For example, the third lens assembly (400) can perform the function of a compensator that accurately forms an image at the actual image sensor location from the second lens assembly (300) that is the variable.

[0063] And the second lens assembly (300) and the third lens assembly (400) can be driven by electromagnetic force resulting from the interaction between the coil and the magnet. The above description may be applied to the lens assembly described later. Additionally, the second lens assembly (300) and the third lens assembly (400) can move along the optical axis direction or a first direction parallel to the optical axis direction. Furthermore, the second lens assembly (300) to the third lens assembly (400) can move along the optical axis direction independently or dependently from each other.

[0064] Furthermore, the first lens assembly (200) may be located at the front end of the second lens assembly (300) or at the rear end of the third lens assembly (400). That is, the first lens assembly (200) may be located adjacent to the first camera actuator or adjacent to the image sensor. And the first lens assembly (200) may be in a fixed state.

[0065] In the present invention, the second lens assembly (300) and the third lens assembly (400) may move along the optical axis direction. The first lens assembly (200) may be located at the front end of the second lens assembly (300) or at the rear end of the third lens assembly (400). The first lens assembly (200) may not move along the optical axis direction. That is, the first lens assembly (200) may be a fixed part. Additionally, the second and third lens assemblies may be movable parts.

[0066] Meanwhile, when an actuator for OIS and an actuator for AF / Zoom are arranged according to an embodiment of the present invention, magnetic field interference with the magnet for AF / Zoom can be prevented during OIS operation. Since the magnet of the first camera actuator (A1) is arranged separately from the second camera actuator (A2), magnetic field interference between the first camera actuator (A1) and the second camera actuator (A2) can be prevented. In this specification, OIS may be used interchangeably with terms such as hand shake correction, optical image stabilization, optical image correction, and shake correction.

[0067] Before describing the lens assembly according to an embodiment of the present invention, the present invention will be described based on the second camera actuator (A2). This description is limited only to facilitate a sufficient understanding of the invention and is not necessarily limited to the illustrated second camera actuator (A2).

[0068] In addition, in the detailed description of the invention, the background and specific arrangement relationships described above have been mentioned to aid in a sufficient understanding of the invention; however, this is not necessarily limited thereto, and is intended only to aid in understanding the second camera actuator (A2) which will be explained in detail through the drawings described later, and should not be interpreted as being limited to what has been mentioned.

[0069] Meanwhile, as illustrated in FIG. 4, a camera actuator (A2) according to an embodiment of the present invention may include a housing (100), a first lens assembly (200), a second lens assembly (300), a third lens assembly (400), and a driving module (510, 520) including a first driving unit (510) and a second driving unit (520).

[0070] Before explaining this, to explain the directions in detail, the first direction is a direction parallel to the optical axis direction and can mean both directions facing upward and downward with respect to FIG. 4, and the second direction is perpendicular to the first direction and can mean both directions facing from the first driving unit (510) to the second driving unit (520) and from the second extension unit (520) to the first driving unit (510), and can mean directions facing from the upper left to the lower right and from the lower right to the upper left with respect to FIG. 4.

[0071] Additionally, the third direction is a direction perpendicular to the first and second directions and may include a direction from the front to the rear of the housing (100) and a direction from the rear to the front of the housing (100). Here, the third direction may include a direction from the lower left to the upper right and a direction from the upper right to the lower left, based on FIG. 4.

[0072] To describe the second camera actuator (A2) according to an embodiment of the present invention based on the above description, first, the housing (100) described above can form the exterior of the camera actuator (A2) according to an embodiment of the present invention and can have a space formed inside.

[0073] Here, a first lens assembly (200) is disposed on one side of the housing (100) in a first direction, and the first lens assembly (200) may include a first lens group (210) and a first barrel portion (220).

[0074] In addition, a second lens assembly (300) and a third lens assembly (400) are positioned inside the housing (100) and are moved along the optical axis direction by the first driving unit (510) and the second driving unit (520), and the first lens assembly (200) can be fixed to the outside of the housing (100).

[0075] At this time, the first lens assembly (200) is fixed to the outside of the housing (100), and a separate cover member may be provided between the first lens assembly (200) and the housing (100), but is not limited thereto.

[0076] Meanwhile, the second lens assembly (300) and the third lens assembly (400) can be moved along the optical axis direction or a first direction parallel to the optical axis direction by the driving module (510, 520).

[0077] Here, the second lens assembly (300) may include a second lens group (310) and a second barrel portion (320) surrounding the second lens group (310), as shown in FIG. 4. Additionally, the third lens assembly (400) may include a third lens group (410) and a third barrel portion (420) surrounding the third lens group (410).

[0078] At this time, the first driving unit (510) may include a first coil (511) and a second coil (512) spaced apart in a first direction, and may include a first magnet (513) disposed on the second barrel unit (320). The second lens assembly (300) may be moved in the first direction by the electrical interaction between the first coil (511) and the second coil (512) and the first magnet (513). Additionally, the second lens assembly (300) may be a zoom lens assembly. That is, the second lens assembly (300) may perform a zooming function.

[0079] Additionally, the second driving unit (520) may include a third coil (521) and a fourth coil (522) spaced apart in the first direction, and may include a second magnet (523) disposed on the third barrel unit (420). The third lens assembly (400) may be moved in the first direction by the electrical interaction between the third coil (5221), the fourth coil (522), and the second magnet (523). Furthermore, the third lens assembly (400) may be an auto-focusing lens assembly. That is, the third lens assembly (400) may perform an auto-focusing function.

[0080] Meanwhile, the control unit (600) may be positioned adjacent to the first driving unit (510). Specifically, the control unit (600) may be positioned to overlap the first coil (511) and the second coil (512) in the first direction. Accordingly, the maximum length of the first coil (511) and the second coil (512) in the first direction may be smaller than the maximum length of the third coil (521) and the fourth coil (522) in the first direction.

[0081] Alternatively, the length of the first coil (511) in the first direction may be smaller than the length of the third coil (521) or the fourth coil (522) in the first direction, and the length of the second coil (512) in the first direction may be smaller than the length of the third coil (521) or the fourth coil (522) in the first direction. Accordingly, the control unit (600) may overlap with the first coil (511) and the second coil (512) in the first direction, and overlap with either the third coil (521) or the fourth coil (522) in the second direction.

[0082] That is, the control unit (600) of the second camera actuator (A2) according to an embodiment of the present invention may be positioned on one side of the first driving unit (510) in the first direction. Through this, the length of the second camera actuator (A2) in the first direction can be effectively reduced, thereby enabling miniaturization.

[0083] Meanwhile, prior to explaining the operation of the second camera actuator (A2) according to an embodiment of the present invention, FIGS. 5 and 6 briefly illustrate and explain the housing (100), the first lens assembly (200), the second lens assembly (300), and the third lens assembly (400) to prevent misinterpretation due to the complex configuration. This is intended only to aid in understanding the explanation and should not be interpreted as being limited to what is illustrated.

[0084] To explain the above in more detail, a second camera actuator according to an embodiment of the present invention comprises a housing (100), a first lens assembly disposed on the housing (100), a second lens assembly (300) and a third lens assembly (400) that move in a first direction within the housing (100), a driving module (510, 520) that moves the second lens assembly (300) and the third lens assembly (400) in the first direction, and a control unit (600) that controls the driving module (510, 520).

[0085] Here, the control unit (600) moves at least one of the second lens assembly (300) or the third lens assembly (400) by repeating at least once a first section (T1) for setting a first gain (G1) to the driving module (510, 520) and a second section (T2) for setting a second gain (G2) to the driving module (510, 520). Additionally, in a movement section (S) in which at least one of the second lens assembly (300) or the third lens assembly (400) is moved in a first direction, the first section (T1) is relatively adjacent to the initial position (SP) of the movement section (S), and the second section (T2) is relatively adjacent to the arrival position (EP) of the movement section (S).

[0086] To explain this in detail, refer to FIGS. 5 to 8. When a magnification is input to the control unit (600) at an initial position (SP) based on the second lens assembly (300), the control unit (600) sets an arrival position (EP) and controls the driving module (510, 520) to the set arrival position (EP) to move the second lens assembly (300) in the first direction.

[0087] The reason for explaining based on the second lens assembly (300) here is that the second lens assembly (300) is a zoom lens assembly that performs a zooming function as described above, and the third lens assembly (400) is an AF lens assembly that performs an auto focusing function. In the case of auto focusing, since the control unit (600) continuously moves the third lens assembly (400) in the first direction to perform focusing even without performing separate operations, the explanation is based on the second lens assembly (300) in which a moving section (S) is formed when the magnification is input to the control unit (600).

[0088] Alternatively, when the third lens assembly (400) performs auto-focusing, it generally has a fine driving interval, and when it has such an interval, it is necessary to maintain a relatively low gain to ensure fine adjustment. However, in the case of the zooming function, since the magnification is input according to the user's needs, such as suddenly increasing or decreasing the magnification, it is necessary to prevent collisions by securing driving force on the driving section of the second lens assembly (300) through changes in gain. Therefore, the control unit (600) can move only the second lens assembly (300) by repeating the first section (T1) and the second section (T2) at least once through the driving modules (510, 520).

[0089] However, since this is a description limited to the second lens assembly (300) being a zoom lens assembly that performs a zooming function, if the third lens assembly (400) performs a zooming function according to the design, the control unit (600) can move only the third lens assembly (400) by repeating the first section (T1) and the second section (T2) at least once through the driving modules (510, 520). That is, it should not be interpreted as being limited to the first and second.

[0090] As described above, when a magnification is input to the control unit (600), the movement section (S) of the second lens assembly (300) is set according to the magnification, and the driving module (510, 520) is controlled from the initial position (SP) to the arrival position (EP) to move the second lens assembly (300) in the first direction.

[0091] Here, the control unit (600) may perform the first section (T1) at a location adjacent to the initial position (SP) and the second section (T2) at a location adjacent to the arrival position (EP). For example, if the second lens assembly (300) is placed at the initial position (SP) of the moving section (S) while in a stationary state, the first section (T1) may be performed first up to the arrival position (EP) of the moving section (S), and the second section (T2) may be performed subsequently.

[0092] When performing in this manner, a first gain (G1) is applied in the first section (T1) and a second gain (G2) is applied in the second section (T2), and it may be desirable for the first gain (G1) to have a value greater than the second gain (G2). If the first gain (G1) is lower than the second gain (G2), there may be a problem in that the driving force of the second lens assembly (300) is lowered in the first section (T1) during the process of moving from the initial position (SP) to the arrival position (EP), and a relatively long time is required to secure the input magnification. Additionally, if the second gain (G2) is higher than the first gain (G1), a problem may occur in which the second lens assembly (300) has a relatively high driving force at the arrival position (EP), causing a collision with the first lens assembly, which may result in damage to the first lens assembly and the second lens assembly (300).

[0093] Accordingly, it is preferable that the first gain (G1) is lower than the second gain (G2), and it may be more preferable that the second gain (G2) is less than or equal to half of the first gain (G1). For example, if the first gain (G1) is 100, it may be preferable that the second gain (G2) is 50 or less, exemplarily 30.

[0094] Additionally, the first section (T1) corresponds to a section for the second lens assembly (300) to move as quickly as possible to the arrival position (EP), and the second section (T2) corresponds to a section for the second lens assembly (300) to clearly arrive at the arrival position (EP).

[0095] Accordingly, the control unit (600) can apply a relatively high first gain (G1) in the first section (T1) to secure the driving force of the second lens assembly (300), and apply a relatively low second gain (G2) in the second section (T2) to control it so that it can clearly arrive at the arrival position (EP).

[0096] As described above, the length of the first section (T1) in the first direction may be longer than the length of the second section (T2), but is not necessarily limited thereto. For example, if the movement section (S) is a fine movement, the length of the first section (T1) in the first direction may be shorter than the length of the second section (T2).

[0097] Meanwhile, to explain the second section (T2), refer to FIG. 6. As shown in FIG. 6, the second section (T2) may refer to a section within a pre-set range based on the arrival position (EP).

[0098] For example, even though the second gain (G2) is applied in the second section (T2), there may be cases where the destination position (EP) is moved slightly more or less than the destination position due to the driving force in the first section (T1) where the first gain (G1) is applied. Accordingly, the second section (T2) has a pre-set range based on the destination position (EP), and can perform zooming by moving in both directions rather than one direction while the second gain (G2) is applied.

[0099] To explain this in detail, the length (L) in the first direction of the second section (T2) may be the length between a first point (AP) that has moved beyond the arrival position (EP) and a second point (BP) that has moved less than the arrival position (EP), based on the arrival position (EP). For example, it may be equal to the sum of the first-direction interval between the first point (AP) and the arrival position (EP) and the first-direction interval between the second point (BP) and the arrival position (EP).

[0100] In this way, a relatively high first gain (G1) is applied in the first section (T1) to secure high driving force, and a relatively low second gain (G2) is set in the second section (T2), and fine adjustment is performed up to the arrival position (EP) located within the first point (AP) and the second point (BP). Since the second section (T2) is a section adjacent to the arrival position (EP), even if the first lens assembly and the arrival position (EP) are adjacent, the second gain (G2) in the second section (T2) is applied, thereby effectively preventing damage to the lens caused by a collision between the first lens assembly and the second lens assembly (300).

[0101] However, if the device moves beyond the destination position (EP) to the first point (AP), the first point (AP) may already be a location where it collides with the first lens assembly. Therefore, it may be desirable for the second section (T2) to be the section between the second point (BP) and the destination position (EP). Specifically, the second point (BP) may be the starting point of the second section (T2) where the second gain (G2) is input after the section where the first gain (G1) of the first section (T1) is applied to the driving module (510, 520) has ended.

[0102] That is, the first section (T1) refers to a section separated from the arrival position (EP), and the second section (T2) may refer to a section between the first section (T1) and the arrival position (EP). More specifically, the second section (T2) may refer to a section from the second point (BP) and the arrival position (EP) until the second gain (G2) is applied to the driving module (510, 520) to reach the arrival position (EP).

[0103] To summarize, since a collision of the second lens assembly (300) may occur at the first point (AP), the second lens assembly (300) is not moved to the section between the first point (AP) and the arrival position (EP), and the control unit (600) can effectively prevent damage to the second lens assembly (300) by applying a second gain (G2) to the driving module (510, 520) between the second point (BP) and the arrival position (EP). Alternatively, it may be most desirable to interpret the length (L) in the first direction of the second section (T2) as the interval in the first direction between the second point (BP) and the arrival position (EP).

[0104] Meanwhile, when the control unit (600) determines that the second lens assembly (300) has arrived at the arrival position (EP), it may set a third gain (G3) in the driving module (510, 520) and maintain the third gain (G3) until a new moving section (S) is set. Here, the third gain (G3) may be the same as the first gain (G1) or the second gain (G2).

[0105] For example, when the second lens assembly (300) reaches the arrival position (EP), the control unit (600) can prevent sudden acceleration of the second lens assembly (300) by setting a third gain (G3) to the driving module (510, 520) before a new movement section (S) is input. To this end, since it is desirable to maintain a relatively low gain rather than a relatively high gain, a gain equal to the second gain (G2), which is lower than the first gain (G1), may be applied. However, applying the second gain (G2) is merely one example, and when the arrival position (EP) is reached, the control unit (600) may apply a gain lower than the second gain (G2) to the driving module (510, 520). That is, the third gain (G3) may be lower than the second gain (G2).

[0106] To explain this more easily, refer to Figures 7 and 8. First, in Figures 7 and 8, the X-axis represents time, and the Y-axis represents position.

[0107] First, referring to FIG. 7, when a magnification is input to the control unit (600) and a movement section (S) is set as shown in FIG. 7, the control unit (600) can move the second lens assembly (300) in the first direction by applying a first gain (G1) to the driving module (510, 520) at the initial position (SP). Here, since the first gain (G1) is a relatively high gain, it moves at a fast speed, and when adjacent to the arrival position (EP), the control unit (600) can drive the second lens assembly (300) slowly by applying a second gain (G2) to the driving module (510, 520).

[0108] When comparing this according to time, in the first section (T1), the movement change of the second lens assembly (300) is large and a relatively short time is required as the first gain (G1) is set in the driving module (510, 520), but in the second section (T2), the movement change of the second lens assembly (300) is not large and a relatively long time may be required so that the second lens assembly (300) clearly arrives at the arrival position (EP) as the second gain (G2) is set in the driving module (510, 520). In addition, if the control unit (600) determines that the arrival position (EP) has been reached in the second section (T2), it may apply a third gain (G3) to the driving module (510, 520).

[0109] Accordingly, zooming can be performed quickly with high driving force, while preventing damage caused by collision between lens assemblies (200, 300, 400).

[0110] Meanwhile, in the case where the multiplier is set multiple times, or alternatively, when the multiplier is input multiple times to the control unit (600) and the movement section (S) is set multiple times so that the first arrival position (EP1) and the second arrival position (EP2) are set, as shown in FIG. 8, in the first movement section (S), the first section (T1) and the second section (T2) can be repeated at least once to reach the first arrival position (EP1).

[0111] When the movement section (S) from the first arrival position (EP1) to the second arrival position (EP2) is reset, the second lens assembly (300) can be moved to the second arrival position (EP2) by repeating at least once the third section, to which the third gain (G3) is applied, and the fourth section, to which the fourth gain (G4) is applied, from the first arrival position (EP1) to the second arrival position (EP2). Here, the third gain (G3) may be equal to the first gain (G1), and the fourth gain (G4) may be equal to the second gain (G2). That is, during the process of reaching the first arrival position (EP1) and the process of reaching the second arrival position (EP2), the second lens assembly (300) can effectively prevent collisions at the arrival position (EP) while performing fast zooming through the first section (T1) and the third section.

[0112] Although not explicitly stated, there may be cases where a first arrival position (EP1) is set and a second lens assembly (300) is positioned in either the first section (T1) or the second section (T2), but a new magnification is input to the control unit (600) and a second arrival position (EP2) is set.

[0113] For example, if a second gain (G2) is set in the driving module (510, 520) in the second section (T2) and a new magnification is input to the control unit (600) to set the second arrival position (EP2) while moving toward the arrival position (EP), the control unit (600) can apply the first gain (G1) to the driving module (510, 520) again at the moment the second arrival position (EP2) and the new moving section (S) are set to drive the second lens assembly (300) quickly, and apply the second gain (G2) while adjacent to the second arrival position (EP2).

[0114] That is, even if multiple magnifications are input to the control unit (600), the control unit (600) applies a second gain (G2) to the driving module (510, 520) when the second lens assembly (300) is adjacent to the arrival position (EP) to prevent oscillation of the second lens assembly (300), thereby effectively preventing damage to the driving force and the lens assembly (200, 300, 400).

[0115] We have examined preferred embodiments according to the invention, and it is obvious to those skilled in the art that, in addition to the embodiments described above, the invention may be embodied in other specific forms without departing from the spirit or scope thereof.

[0116] Therefore, the embodiments described above should be regarded as exemplary rather than limiting, and accordingly, the present invention is not limited to the description above but may be modified within the scope of the appended claims and their equivalents.

Claims

1. Housing; A first lens assembly disposed on the above housing; A second lens assembly and a third lens assembly that move in a first direction parallel to the optical axis within the above housing; A driving module for moving the second lens assembly and the third lens assembly in the first direction; and It includes a control unit that controls the above-mentioned drive module, and The above control unit is, At least one of the second lens assembly or the third lens assembly is moved by repeating the first section for setting a first gain in the driving module and the second section for setting a second gain in the driving module at least once, and A camera actuator in which at least one of the second lens assembly or the third lens assembly is moved in the first direction, wherein the first section is relatively adjacent to the initial position of the moving section and the second section is relatively adjacent to the arrival position of the moving section.

2. In Paragraph 1, The above second gain is a camera actuator lower than the above first gain.

3. In Paragraph 2, A camera actuator in which the second gain is less than or equal to half of the first gain.

4. In Paragraph 1, The above control unit is a camera actuator that moves only the second lens assembly by repeating the first section and the second section at least once through the driving module.

5. In Paragraph 4, The above second lens assembly is a zoom lens assembly, and The above third lens assembly is a camera actuator that is an AF (Auto Focus) lens assembly.

6. In Paragraph 4, A camera actuator that, when the control unit determines that the second lens assembly has reached the arrival position, sets a third gain in the driving module and maintains the third gain during the period prior to the setting of the movement section.

7. In Paragraph 6, The above third gain is a camera actuator identical to either the above first gain or the above second gain.

8. In Paragraph 7, The above third gain is a camera actuator identical to the above second gain of the above second section relatively adjacent to the above arrival position.

9. In Paragraph 1, The above second section is a camera actuator that is a section within a pre-set range based on the above arrival position.

10. In Paragraph 9, The above second section is a camera actuator that is the section between the above arrival location and the above first section.

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