Patent Description:
Each of <CIT>, <CIT> and <CIT> discloses a camera device. Cameras are devices that capture an image or a video of a subject and are mounted on portable devices, drones, vehicles, or the like. The camera device may have an image stabilization (IS) function for correcting or preventing image shake caused by user movement to improve image quality, an auto focusing (AF) function for automatically adjusting an interval between an image sensor and a lens to adjust a focal length of a lens, and a zooming function for increasing or decreasing a magnification of a subject at a long distance through a zoom lens to photograph the subject.

Meanwhile, in a camera module, a zoom actuator is used for a zooming function, frictional torque is generated when a lens moves due to mechanical movement of an actuator, and technical problems such as a decrease in driving force, an increase in power consumption, or the degradation of control characteristics are caused by the frictional torque.

In particular, in order to obtain the best optical characteristics using a plurality of zoom lens groups in a camera module, alignment between the plurality of lens groups and the alignment between the plurality of lens groups and an image sensor should be well made. When decentering occurs in which a center of a spherical surface between the lens groups deviates from an optical axis, a tilting phenomenon occurs in which a lens is tilted, or a phenomenon occurs in which central axes of the lens groups and the image sensor are not aligned, an angle of view changes or defocusing occurs, which adversely affects image quality or resolution.

In addition, when a zooming function, an AF function, and an optical image stabilizer (OIS) function are all included in a camera module, there is a problem in that a magnet for an OIS, a magnet for zooming, and a magnet for an AF are disposed close to each other to cause magnetic field interference.

The present invention is directed to providing a camera actuator applicable to an ultra-slim, ultra-miniature, and high-resolution camera, and a camera device including the same.

The present invention is directed to providing a camera actuator capable of precisely performing zooming and auto focusing (AF) while alignment between lens groups is maintained, and a camera device including the same.

The present invention is directed to providing an auto focusing function in a fixed zoom optical system.

The present invention is directed to providing a hand shake preventing function in a fixed zoom optical system.

The present invention is directed to providing a fixed zoom optical system of which a total track length (TTL) is fixed.

According to an embodiment of the present invention, a camera device includes a base, a first lens assembly which is disposed in the base and includes a first lens group and a first lens support unit to which the first lens group is fixed, a second lens assembly which is disposed in the base and includes a second lens group and a second lens support unit to which the second lens group is fixed, and a driving unit configured to drive the second lens assembly, wherein a first stopper member and a second stopper member are formed on an inner wall of the second lens support unit and spaced apart from each other by an interval greater than a height of the first lens assembly in a moving direction of the second lens support unit, the first lens assembly is accommodated between the first stopper member and the second stopper member in the second lens support unit, and the second lens assembly is configured to move together with the first lens assembly in the base.

The driving unit may include a coil driving unit disposed on at least one of a first inner wall and a second inner wall, which faces the first inner wall, of the base and a magnet driving unit disposed on the second lens support unit to face the coil driving unit, and the second lens assembly may be moved along the first inner wall and the second inner wall by an interaction between the coil driving unit and the magnet driving unit.

The camera device may further include a magnet disposed on the first lens assembly, and a first yoke and a second yoke fixed at a certain interval on one surface of the base disposed to face the magnet, wherein, according to a position of the second lens assembly, an attractive force may act between the magnet and the first yoke, or an attractive force may act between the magnet and the second yoke.

In a first zooming mode, the attractive force may act between the first yoke and the magnet of the first lens assembly moved together with the second lens assembly in a first direction, and in a second zooming mode, the attractive force may act between the second yoke and the magnet of the first lens assembly moved together with the second lens assembly in a second direction opposite to the first direction.

By the attractive force acting between the magnet and the first yoke, the first lens assembly may be further moved in the first direction until the first lens assembly comes into contact with the first stopper member, and by the attractive force acting between the magnet and the second yoke, the first lens assembly may be further moved in the second direction until the first lens assembly comes into contact with the second stopper member.

The second lens assembly may perform focusing in a state in which the first lens assembly is in contact with the first stopper member or in a state in which the first lens assembly is in contact with the second stopper member.

A guide part may be disposed adjacent to at least one of a first inner wall and a second inner wall of the base, a groove corresponding to the guide part may be formed in an outer circumferential surface of the second lens support unit, and a ball may be disposed between the guide part and the groove.

The camera device may further include a guide pin fixed to the base to be parallel to an optical axis, wherein the second lens support unit may move along the guide pin.

According to an embodiment of the present invention, an optical system includes a first lens group and a second lens group which are sequentially arranged in a direction from an object toward an image and include a plurality of lenses, wherein the second lens group is movable in an optical axis direction. According to an embodiment, the first lens group has positive refractive power, the second lens group has negative refractive power. According to an embodiment, a total track length (TTL) is fixed within <NUM>.

According to an embodiment, when focusing is performed from the infinity focus to the nearest focus, a movement stroke of the second lens group is within <NUM>.

According to embodiments of the present invention, it is possible to provide a camera actuator applicable to an ultra-slim, ultra-miniature, and high-resolution camera, and a camera device including the same. In particular, it is possible to provide a camera actuator capable of implementing a zooming function and an auto focusing (AF) function while alignment between a plurality of lens groups is maintained. In addition, according to embodiments of the present invention, step zooming can be implemented using a minimum control signal.

According to embodiments of the present invention, a total track length (TTL) can be fixed, and concurrently, both an AF function and an optical image stabilizer (OIS) function can be implemented, thereby providing advantages of miniaturization and weight reduction.

According to embodiments of the present invention, since only a second lens group is separated and moved, a weight loaded on a driving system can be reduced, thereby reducing an amount of current consumption.

While the present invention is open to various modifications and alternative embodiments, specific embodiments thereof will be described and shown by way of example in the accompanying drawings.

It should be understood that, although the terms including ordinal numbers such as first, second, and the like may be used herein to describe various elements, the elements are not limited by the term. These terms are only used for the purpose of distinguishing one element from another element. For example, without departing from the scope of the appended claims, a second element could be termed a first element, and similarly a first element could be also termed a second element. The term "and/or" includes any one or all combinations of a plurality of associated listed items.

In the case that one component is described as being "connected" or "linked" to another component, it may be connected or linked to the corresponding component directly or other components may be present therebetween. On the other hand, in the case that one component is described as being "directly connected" or "directly linked" to another component, it should be understood that other components are not present therebetween.

It is to be understood that terms used herein are for the purpose of the description of particular embodiments and not for limitation. A singular expression includes a plural expression unless the context clearly indicates otherwise. It will further be understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Unless defined otherwise, all the terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. It will further be understood that the terms, such as those defined in commonly used dictionaries, should be interpreted as having meanings that are consistent with their meanings in the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless expressly defined otherwise herein.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings, and the same or corresponding elements will be given the same reference numbers regardless of drawing symbols, and redundant descriptions will be omitted.

<FIG> is a perspective view illustrating an example of a camera device, <FIG> is a perspective view illustrating the camera shown in <FIG> from which a shield can is removed, and <FIG> is a plan view of the camera shown in <FIG>.

Referring to <FIG>, a camera device <NUM> may include one or more camera modules. For example, the camera device <NUM> may include a first camera module 1000A and a second camera module 1000B. The first camera module 1000A and the second camera module 1000B may be covered by a certain shield can <NUM>.

Referring to <FIG>, and <FIG> together, the first camera module 1000A may include one or more actuators. For example, the first camera module 1000A may include a first actuator <NUM> and a second actuator <NUM>.

The first actuator <NUM> may be electrically connected to a circuit board <NUM> of a first group, the second actuator <NUM> may be electrically connected to a circuit board <NUM> of a second group, and although not shown, the circuit board <NUM> of the second group may be electrically connected to the circuit board <NUM> of the first group. The second camera module 1000B may be electrically connected to a circuit board <NUM> of a third group.

The first actuator <NUM> may be a zoom actuator or an auto focusing (AF) actuator. For example, the first actuator <NUM> may support one or more lenses and may move the lenses according to a control signal of a certain control unit to perform an AF function or a zooming function.

The second actuator <NUM> may be an optical image stabilizer (OIS) actuator.

The second camera module 1000B may include a fixed focal length lens disposed in a certain barrel (not shown). The fixed focal length lens may be referred to as a "single focal length lens" or a "single lens.

The second camera module 1000B may be disposed in a certain housing (not shown) and may include an actuator (not shown) capable of driving a lens unit. The actuator may be a voice coil motor, a micro actuator, a silicon actuator, or the like and may be applied as various types such as a capacitive type, a thermal type, a bimorph type, and an electrostatic force type, but the present invention is not limited thereto.

Next, <FIG> is a perspective view of the first camera module shown in <FIG>, and <FIG> is a side cross-sectional view of the first camera module shown in <FIG>.

Referring to <FIG>, the first camera module 1000A may include the first actuator <NUM> configured to perform a zooming function and an AF function and the second actuator <NUM> disposed at one side of the first actuator <NUM> and configured to perform an OIS function.

Referring to <FIG>, the first actuator <NUM> may include an optical system and a lens driving unit. For example, at least one of a first lens assembly <NUM>, a second lens assembly <NUM>, a third lens assembly <NUM>, and a guide pin <NUM> may be disposed in the first actuator <NUM>.

In addition, the first actuator <NUM> may include a coil driving unit <NUM> and a magnet driving unit <NUM> to perform a high-magnification zooming function.

For example, the first lens assembly <NUM> and the second lens assembly <NUM> may be moving lenses which are moved through the coil driving unit <NUM>, the magnet driving unit <NUM>, and the guide pin <NUM>, and the third lens assembly <NUM> may be a fixed lens, but the present invention is not limited thereto. For example, the third lens assembly <NUM> may perform a function of a focator for forming an image of light at a specific position, and the first lens assembly <NUM> may perform a function of a variator for re-forming the image formed by the third lens assembly <NUM>, which is the focator, at a different position. Meanwhile, in the first lens assembly <NUM>, due to many changes in a distance to a subject or an image distance, a change in magnification may be large, and the first lens assembly <NUM> that is the variator may play an important role in a change in focal length or magnification of an optical system. Meanwhile, an image point, at which an image is formed by the first lens assembly <NUM> that is the variator, may be slightly different according to positions. Accordingly, the second lens assembly <NUM> may perform a function of compensating a position of an image formed by the variator. For example, the second lens assembly <NUM> may perform a function of a compensator for accurately forming an image point, at which an image is formed by the first lens assembly <NUM> that is the variator, at an actual position of an image sensor <NUM>.

For example, the first lens assembly <NUM> and the second lens assembly <NUM> may be driven by an electromagnetic force generated by an interaction between the coil driving unit <NUM> and the magnet driving unit <NUM>.

The certain image sensor <NUM> may be disposed perpendicular to an optical axis direction of parallel light.

Next, the second actuator <NUM> may include a shake correction unit <NUM> disposed in the housing and a prism unit <NUM> disposed on the shake correction unit <NUM>. The shake correction unit <NUM> may include a shaper member <NUM> and a lens member <NUM> and may include a magnet driving unit <NUM> and a coil driving unit 72C. Here, the lens member <NUM> may be used interchangeably with a liquid lens, a fluid lens, a variable prism, or the like. A shape of the lens member <NUM> may be reversibly deformed by a pressure applied to a surface of the lens member <NUM>, thereby changing an optical path of light passing through the lens member <NUM>. For example, the lens member <NUM> may include a fluid surrounded by an elastic membrane. The shaper member <NUM> may be combined with, connected to, or in direct contact with the lens member <NUM>, and pressure may be applied to the lens member <NUM> due to movement of the shaper member <NUM>. Thus, the shape of the lens member <NUM> may be reversibly deformed, thereby changing an optical path of light passing through the lens member <NUM>. As will be described below, the movement of the shaper member <NUM> may occur due to an interaction between the magnet driving unit <NUM> and the coil driving unit 72C.

As described above, an OIS can be implemented by controlling an optical path of light passing through the lens member <NUM>, thereby minimizing the occurrence of a decentering or tilting phenomenon and providing superior optical characteristics.

Since <FIG> and descriptions with reference thereto are provided for the purpose of describing the overall structure and operation principle of the camera device according to the embodiment of the present invention, embodiments of the present invention are not limited to the detailed configuration shown in <FIG>.

Hereinafter, the first actuator for implementing a zooming function and an AF function according to the embodiment of the present invention will be described in more detail.

<FIG> is a perspective view of the first actuator according to the embodiment of the present invention. <FIG> is a perspective view illustrating a state in which a base and a yoke are removed from the first actuator of <FIG>. <FIG> is a cross-sectional view of the first actuator in <FIG>. <FIG> is a perspective view illustrating the base and the yoke in the first actuator of <FIG>. <FIG> is an exploded perspective view of the first lens assembly and the second lens assembly of <FIG>. For reference, according to <FIG>, although the first actuator <NUM> for implementing a zooming function and an AF function is illustrated as including the first lens assembly <NUM>, the second lens assembly <NUM>, and the third lens assembly <NUM>, since embodiments of the present invention mainly relate to the structures of the first lens assembly <NUM> and the second lens assembly <NUM> which are the moving lenses, the illustration and description of the third lens assembly <NUM>, which is the fixed lens, will be omitted below.

Referring to <FIG>, the first actuator <NUM> includes a base <NUM>, the first lens assembly <NUM>, the second lens assembly <NUM>, and the third lens assembly (not shown).

The first lens assembly <NUM> and the second lens assembly <NUM> are disposed in the base <NUM>, and the first lens assembly <NUM> includes a first lens group <NUM> and a first lens support unit <NUM>. The first lens group <NUM> may be accommodated in the first lens support unit <NUM> and may be fixed to the first lens support unit <NUM>. The second lens assembly <NUM> includes a second lens group <NUM> and a second lens support unit <NUM>. The second lens group <NUM> may be accommodated in the second lens support unit <NUM> and may be fixed to the second lens support unit <NUM>.

According to an embodiment of the present invention, the first lens assembly <NUM> is accommodated in the second lens support unit <NUM> of the second lens assembly <NUM>. To this end, the second lens support unit <NUM> may include an area surrounding an edge of the second lens group <NUM> and an area accommodating the first lens assembly <NUM>. Accordingly, when the second lens assembly <NUM> moves, the first lens assembly <NUM> may move together with the second lens assembly <NUM> without a separate component for driving the first lens assembly <NUM>, and a magnification may be adjusted according to positions and intervals of the first lens group <NUM> in the first lens assembly <NUM>, the second lens group <NUM> in the second lens assembly <NUM>, a third lens group (not shown) in the third lens assembly (not shown), and an image sensor (not shown).

In order to move the second lens assembly <NUM>, a coil driving unit (not shown) may be disposed on each of a first inner wall <NUM> and a second inner wall <NUM> of the base <NUM>, and a magnet driving unit <NUM> may be disposed on each of a first outer wall <NUM> of the second lens support unit <NUM> facing the first inner wall <NUM> of the base <NUM> and a second outer wall <NUM> of the second lens support unit <NUM> facing the second inner wall <NUM> of the base <NUM>. By an electromagnetic interaction between the coil driving unit (not shown) and the magnet driving unit <NUM>, the second lens support unit <NUM> may be moved along the first inner wall <NUM> and the second inner wall <NUM> of the base <NUM>, and the first lens assembly <NUM> accommodated in the second lens support unit <NUM> may be moved together with the second lens support unit <NUM>. That is, a distance or direction in which the second lens support unit <NUM> moves together with the magnet driving unit <NUM> may vary according to an amount or direction of a current flowing through the coil driving unit (not shown). In this case, the second lens support unit <NUM> may move along the base <NUM> through a guide pin, a guide ball, or a guide rail, and a detailed example thereof will be described below.

Meanwhile, according to an embodiment of the present invention, a sensor unit may be further disposed to detect positions of the second lens assembly <NUM> and the first lens assembly <NUM> accommodated in the second lens support unit <NUM> of the second lens assembly <NUM> and control movements thereof. The sensor unit may include a sensing magnet <NUM> and a Hall sensor (not shown). The sensing magnet <NUM> may be fixed to the second lens support unit <NUM> to move together with the second lens support unit <NUM>. The Hall sensor (not shown) may be disposed adjacent to the coil driving unit (not shown). For example, the Hall sensor may be disposed adjacent to at least one of the coil driving unit disposed on the first inner wall <NUM> of the base <NUM> and the coil driving unit disposed on the second inner wall <NUM> of the base <NUM>. For example, the Hall sensor may be disposed in an inner circumferential portion of a coil wound to constitute the coil driving unit. The Hall sensor (not shown) may detect a magnetic field of the sensing magnet <NUM> and may detect a position of the sensing magnet <NUM> according to an intensity of the magnetic field. Since the sensing magnet <NUM> moves together with the second lens support unit <NUM>, positions of the first lens assembly <NUM> and the second lens assembly <NUM> may be detected according to the position of the sensing magnet <NUM>, and based on detection results, a control signal for adjusting a magnification may be generated so that a voltage according to the control signal may be applied to the coil driving unit (not shown).

As described above, according to an embodiment of the present invention, the first lens assembly <NUM> is accommodated in the second lens support unit <NUM> of the second lens assembly <NUM> and thus is moved together with the second lens support unit <NUM> as the second lens support unit <NUM> is moved. Accordingly, since there is no need to separately control movement of the first lens assembly <NUM> and the second lens assembly <NUM>, it is possible to minimize the occurrence of a decentering or tilting phenomenon and obtain superior optical characteristics.

More specifically, in order for the second lens support unit <NUM> to accommodate the first lens assembly <NUM>, a first stopper member <NUM> and a second stopper member <NUM> may be formed on an inner wall of the second lens support unit <NUM>. The first stopper member <NUM> and the second stopper member <NUM> may be spaced apart from each other by a certain interval D, and the first lens assembly <NUM> may be accommodated between the first stopper member <NUM> and the second stopper member <NUM>. In this case, the interval D between the first stopper member <NUM> and the second stopper member <NUM> may be greater than a height H of the first lens assembly <NUM>. In addition, an inner diameter of the second lens support unit <NUM> may be greater than an outer diameter of the first lens assembly <NUM>. Accordingly, the first lens assembly <NUM> may move together with the second lens assembly <NUM> and may move between the first stopper member <NUM> and the second stopper member <NUM> of the second lens support unit <NUM>.

Meanwhile, one or more magnets <NUM> may be further disposed on the first lens assembly <NUM>, and at least two yokes <NUM> and <NUM> fixed at a certain interval may be further disposed on at least one surface of the base <NUM> disposed to face the magnet <NUM>.

Here, the yokes <NUM> and <NUM> are made of a metal with magnetism, and when the yokes <NUM> and <NUM> approach the magnet <NUM> within a certain distance, an attractive force acts between the yokes <NUM> and <NUM> and the magnet <NUM>. That is, according to a position of the second lens assembly <NUM>, an attractive force may act between the magnet <NUM> of the first lens assembly <NUM> and a first yoke <NUM>, or an attractive force may act between the magnet <NUM> of the first lens assembly <NUM> and a second yoke <NUM>.

To this end, the magnet <NUM> may be disposed on the first lens assembly <NUM> to face a third inner wall <NUM> between the first inner wall <NUM> and the second inner wall <NUM> of the base <NUM>, and the first yoke <NUM> and the second yoke <NUM> may be disposed apart from each other on the third inner wall <NUM>. Similarly, the magnet <NUM> may be further disposed on the first lens assembly <NUM> to face a fourth inner wall <NUM> facing the third inner wall <NUM> of the base <NUM>, and a third yoke <NUM> and a fourth yoke <NUM> may be disposed apart from each other on the fourth inner wall <NUM>. In this case, the magnet <NUM> disposed to face the third inner wall <NUM> and the magnet <NUM> disposed to face the fourth inner wall <NUM> may be disposed symmetrically with each other, the first yoke <NUM> and the third yoke <NUM> may be symmetrical with each other, and the second yoke <NUM> and the fourth yoke <NUM> may be disposed symmetrically with each other.

In order to describe the structure and operation principle of the first actuator according to the embodiment of the present invention in more detail, <FIG> shows views illustrating a movement process of an actuator device in a telephoto mode according to an embodiment of the present invention, and <FIG> shows views illustrating a movement process of the actuator device in a wide-angle mode according to an embodiment of the present invention.

<FIG> is a side view illustrating a case in which the second lens assembly <NUM> moves in a first direction while accommodating the first lens assembly <NUM> in the telephoto mode. <FIG> is a perspective view of the case of <FIG> is a part of a top view of the case of <FIG> is a perspective view illustrating a case in which the first lens assembly <NUM> in <FIG> B is further moved in the first direction by an attractive force with the first yoke <NUM>, and <FIG> is a part of a top view of <FIG>. When a current is applied to the coil driving unit (not shown) to perform zooming in the telephoto mode, by an interaction between the coil driving unit (not shown) and the magnet driving unit <NUM>, the second lens assembly <NUM> to which the magnet driving unit <NUM> is fixed is moved to a certain distance in the first direction. A position of the second lens assembly <NUM> may be detected by an interaction between the sensing magnet <NUM> fixed to the second lens assembly <NUM> to move together with the second lens assembly <NUM> and the Hall sensor disposed adjacent to the coil driving unit (not shown). That is, the Hall sensor (not shown) may detect a magnetic field of the sensing magnet <NUM> to detect a position of the sensing magnet <NUM>, that is, a position of the second lens assembly <NUM>. In this case, the first lens assembly <NUM> moves in the first direction together with the second lens assembly <NUM> in a state of being caught by the second stopper member <NUM>. Thus, an attractive force may act between the magnet <NUM> on the first lens assembly <NUM> and the first yoke <NUM>, the first lens assembly <NUM> may be further moved in the first direction by the attractive force acting between the magnet <NUM> and the first yoke <NUM> until the first lens assembly <NUM> comes into contact with the first stopper member <NUM> to be caught by the first stopper member <NUM>. Accordingly, the first actuator may perform zooming in the telephoto mode. To this end, the first lens assembly <NUM> and the second lens support unit <NUM> may not be connected to each other through a separate coupling member or an adhesive member, and the first lens assembly <NUM> may freely be moved between the first stopper member <NUM> and the second stopper member <NUM> of the second lens support unit <NUM>.

Meanwhile, in a state in which the first lens assembly <NUM> is fixed to the first stopper member <NUM>, the second lens assembly <NUM> is finely moved in the first direction or a second direction, for example, within a distance of <NUM> to perform focusing. In this case, a position of the second lens assembly <NUM> may be detected by an interaction between the sensing magnet <NUM> fixed to the second lens assembly <NUM> to move together with the second lens assembly <NUM> and the Hall sensor disposed adjacent to the coil driving unit (not shown).

<FIG> is a side view illustrating a case in which the second lens assembly <NUM> moves in the second direction while accommodating the first lens assembly <NUM> in the wide-angle mode. <FIG> is a perspective view of the case of <FIG> is a part of a top view of the case of <FIG> is a perspective view illustrating a case in which the first lens assembly <NUM> in <FIG> is further moved in the second direction by an attractive force with the second yoke <NUM>. <FIG> is a part of a top view of the case of <FIG>. When a current is applied to the coil driving unit (not shown) to perform zooming in wide-angle mode, by an interaction between the coil driving unit (not shown) and the magnet driving unit <NUM>, the second lens assembly <NUM> to which the magnet driving unit <NUM> is fixed is moved to a certain distance in the second direction. A position of the second lens assembly <NUM> may be detected by an interaction between the sensing magnet <NUM> fixed to the second lens assembly <NUM> to move together with the second lens assembly <NUM> and the Hall sensor disposed adjacent to the coil driving unit (not shown). That is, the Hall sensor (not shown) may detect a magnetic field of the sensing magnet <NUM> to detect a position of the sensing magnet <NUM>, that is, a position of the second lens assembly <NUM>. In this case, the first lens assembly <NUM> moves in the second direction together with the second lens assembly <NUM> in a state of being caught by the first stopper member <NUM>. Thus, an attractive force may act between the magnet <NUM> on the first lens assembly <NUM> and the second yoke <NUM>, the first lens assembly <NUM> may be further moved in the second direction by the attractive force acting between the magnet <NUM> and the second yoke <NUM> until the first lens assembly <NUM> comes into contact with the second stopper member <NUM> to be caught by the second stopper member <NUM>. Accordingly, the first actuator may perform zooming in the wide-angle mode.

Meanwhile, in a state in which the first lens assembly <NUM> is fixed to the second stopper member <NUM>, the second lens assembly <NUM> is finely moved in the first direction or the second direction, for example, within a distance of <NUM> to perform focusing. In this case, a position of the second lens assembly <NUM> may be detected by an interaction between the sensing magnet <NUM> fixed to the second lens assembly <NUM> to move together with the second lens assembly <NUM> and the Hall sensor disposed adjacent to the coil driving unit (not shown).

Here, for convenience of description, an example of only two zooming modes, that is, the wide-angle mode and the telephoto mode, has been described, but the present invention is not limited thereto. According to an embodiment of the present invention, a magnification can be gradually adjusted in two or more zooming modes according to a position of the yoke and under control of the driving unit.

<FIG> is a graph showing an interaction between a Hall sensor and a sensing magnet applied to the first actuator according to an embodiment of the present invention. <FIG> is a graph showing a stroke of the first lens assembly applied to the first actuator according to an embodiment of the present invention. <FIG> is a graph illustrating a stroke of the second lens assembly applied to the first actuator according to an embodiment of the present invention.

Referring to <FIG>, a horizontal axis indicates a digital code, and a vertical axis indicates a magnetic field. A magnetic field sensed by the Hall sensor may vary according to a position of the sensing magnet, and the Hall sensor may generate or output a digital code according to the sensed magnetic field. Here, the Hall sensor may distinguish and sense an N pole and an S pole. To this end, the Hall sensor may include two Hall sensors. For example, when Hall sensor <NUM> in <FIG> shows a relationship between the N pole and the digital code, Hall sensor <NUM> shows a relationship between the S pole and the digital code. Alternatively, when Hall sensor <NUM> shows the relationship between the S pole and the digital code, Hall sensor <NUM> shows the relationship between the N pole and the digital code.

According to an embodiment of the present invention, a section A in which both the Hall sensor <NUM> and the Hall sensor <NUM> have high magnetic fields may be a use section of the sensing magnet. That is, only when a digital code output from the Hall sensor has a value within the section A, it is possible to control and move the first lens assembly <NUM> or the second lens assembly <NUM>.

Meanwhile, referring to <FIG>, a horizontal axis indicates a control code, and a vertical axis indicates a stroke of the first lens assembly. Referring to <FIG>, a horizontal axis indicates a control code, and a vertical axis indicates a stroke of the second lens assembly.

Referring to <FIG>, it can be seen that the stroke of the first lens assembly, that is, a variable magnification is rapidly changed in a certain control code (for example, about <NUM>). In addition, referring to <FIG>, it can be seen that the stroke of the second lens assembly is rapidly changed in a certain control code (for example, about <NUM>).

Therefore, after a certain control code (for example, about <NUM>) is input to the coil driving unit (not shown) to move the first lens assembly <NUM> and the second lens assembly <NUM> together and perform zooming, a certain control code (for example, about <NUM>) may be input to finely move the second lens assembly <NUM> and perform focusing.

Meanwhile, as described above, the second lens assembly <NUM> may move along the first inner wall <NUM> and the second inner wall <NUM> of the base <NUM> while accommodating the first lens assembly <NUM>, and in this case, the second lens assembly <NUM> may move through a guide pin, a guide ball, or a guide rail.

<FIG> illustrates an example in which the second lens assembly moves along a guide pin according to an embodiment of the present invention.

Referring to <NUM>, the guide pin <NUM> may be disposed parallel to an optical axis, and an end of the guide pin <NUM> may be attached to the base <NUM> or a fixing member in the first actuator (for example, the third lens assembly, or the like). The guide pin <NUM> may be fitted to pass through a guide hole <NUM> formed in the second lens support unit <NUM> of the second lens assembly <NUM>, and the second lens assembly may be moved along the guide pin <NUM>.

<FIG> illustrate an example in which the second lens assembly moves along a guide ball according to an embodiment of the present invention.

Referring to <FIG>, a guide part <NUM> may be disposed adjacent to at least one of the first inner wall <NUM> and the second inner wall <NUM> of the base <NUM>, and a recess <NUM> may be formed in the guide part <NUM> along an optical axis. Although not shown, the guide part <NUM> may be fixed to at least one of the first inner wall <NUM> and the second inner wall <NUM> of the base.

Referring to <FIG>, a groove <NUM> corresponding to the recess <NUM> of the guide part <NUM> may be formed in an outer circumferential surface of the second lens support unit <NUM>. The second lens assembly <NUM> may be moved by a ball <NUM> disposed between the recess <NUM> of the guide part <NUM> and the groove <NUM>. As describe above, when the guide part <NUM> is further disposed between the first inner wall <NUM> and the second inner wall <NUM> of the base <NUM> and the outer circumferential surface of the second lens support unit <NUM>, frictional resistance is reduced by reducing frictional torque generated during movement of the lens assembly, thereby obtaining technical effects of improving a driving force, reducing power consumption, and improving control characteristics during zooming. Accordingly, during zooming, it is possible to minimize frictional torque and also prevent a phenomenon in which a lens is decentered or tilted or central axes of a lens group and an image sensor are not aligned, thereby providing a combined technical effect of considerably improving image quality or resolution.

Although not shown, two guide parts <NUM> may be disposed adjacent to the first inner wall <NUM> and the second inner wall <NUM> to be symmetrical with each other, and the grooves <NUM> may be formed symmetrically with each other in the outer circumferential surface of the second lens support unit <NUM> to face the first inner wall <NUM> and the second inner wall <NUM>.

Although not shown, the guide part <NUM> may be omitted, and the recess <NUM> may be formed directly in at least one of the first inner wall <NUM> and the second inner wall <NUM>.

Hereinafter, the detailed structure of the second actuator will be described in more detail.

<FIG> is a perspective view of the second actuator of the camera device shown in <FIG> in one direction. <FIG> is a perspective view of the second actuator of <FIG> in another direction. <FIG> is a perspective view of a second circuit board and a driving unit of the second actuator of <FIG>. <FIG> is a partially exploded perspective view of the second actuator of <FIG>. <FIG> is a perspective view of the second actuator of <FIG> from which the second circuit board is removed.

Referring to <FIG>, the shake correction unit <NUM> is disposed under the prism unit <NUM> to solve a restriction on a size of a lens of a lens assembly in an optical system when an OIS is implemented, thereby securing a sufficient amount of light.

A second circuit board <NUM> may be connected to a certain power supply (not shown) to apply power to the coil driving unit 72C. The second circuit board <NUM> may include a circuit board having an electrically connectable line pattern, such as a rigid printed circuit board (rigid PCB), a flexible PCB, or a rigid flexible PCB.

The coil driving unit 72C may include one or more unit coil driving units and may include a plurality of coils. For example, the coil driving unit 72C may include a first unit coil driving unit 72C1, a second unit coil driving unit 72C2, a third unit coil driving unit 72C3, and a fourth unit coil driving unit (not shown).

In addition, the coil driving unit 72C may further include Hall sensors (not shown) to detect a position of the magnet driving unit <NUM> to be described below. For example, the first unit coil driving unit 72C1 may include a first Hall sensor (not shown), and the third unit coil driving unit 72C3 may include a second Hall sensor (not shown).

Meanwhile, as described above, the shaper member <NUM> may be disposed on the lens member <NUM>, and the shape of the lens member <NUM> may be deformed according to movement of the shaper member <NUM>. In this case, the magnet driving unit <NUM> may be disposed on the shaper member <NUM>, and the coil driving unit 72C may be disposed in the housing <NUM>.

Referring to <FIG>, in the housing <NUM>, a certain opening <NUM> through which light may pass may be formed in a housing body <NUM>. The housing <NUM> may include a housing side portion 1214P extending upward from the housing body <NUM> and having a hole <NUM> formed such that the coil driving unit 72C is disposed therein.

For example, the housing <NUM> may include a first housing side portion 1214P1 extending upward from the housing body <NUM> and having a hole 1214H1 formed such that the coil driving unit 72C is disposed therein and a second housing side portion 1214P2 having a hole 1214H2 formed such that the coil driving unit 72C is disposed therein.

According to an embodiment, the coil driving unit 72C may be disposed on the housing side 1214P, the magnet driving unit <NUM> may be disposed on the shaper member <NUM>, and the shaper member <NUM> may be moved by an electromagnetic force between the coil driving unit 72C and the magnet driving unit <NUM> according to a voltage applied to the coil driving unit 72C. Accordingly, the shape of the lens member <NUM> is reversibly deformed, and an optical path of light passing through the lens member <NUM> is changed, thereby implementing an OIS.

More specifically, the shaper member <NUM> may include a shaper body having a hole, through which light may pass, formed therein, and protrusions extending laterally from the shaper body. The lens member <NUM> may be disposed under the shaper body, and the magnet driving unit <NUM> may be disposed on the protrusion of the shaper member <NUM>. For example, a part of the magnet driving unit <NUM> may be disposed on the protrusion disposed at one side of the shaper member <NUM>, and the remaining part thereof may be disposed on the protrusion disposed at the other side of the shaper member <NUM>. In this case, the magnet driving unit <NUM> may be disposed to be coupled to the shaper member <NUM>. For example, a groove may be formed in the protrusion of the shaper member <NUM>, and the magnet driving unit <NUM> may be fitted into the groove.

Meanwhile, a fixed prism <NUM> may be a right-angled prism and may be disposed inside the magnet driving unit <NUM> of the shake correction unit <NUM>. In addition, a certain prism cover <NUM> may be disposed at an upper side of the fixed prism <NUM> so that the fixed prism <NUM> may be pressed against and coupled to the housing <NUM>.

<FIG> illustrates an optical system according to a first embodiment of the present invention.

Referring to <FIG>, the optical system according to the first embodiment of the present invention includes a first lens group <NUM> and a second lens group <NUM> sequentially arranged in a direction from an object toward an image. Here, the lens groups may correspond to the lens groups described above with reference to <FIG>.

According to an embodiment of the present invention, the first lens group <NUM> includes a plurality of lenses. The first lens group <NUM> is fixed with respect to an image side. That is, the plurality of lenses may be fixed with respect to the image side. In this case, the first lens group <NUM> may include two or more lenses. When the first lens group <NUM> includes three or more lenses, an overall size of the optical system may increase. According to an embodiment, the first lens group <NUM> may include two lenses. In this case, the first lens group <NUM> may include a first lens and a second lens.

The first lens group <NUM> may have positive refractive power. The first lens group <NUM> may have an effective focal length (EFL) in a range of greater than <NUM> and less than <NUM>. The first lens group <NUM> may have an EFL in a range of greater than <NUM> and less than <NUM>. The first lens group <NUM> may have an EFL in a range of greater than <NUM> and less than <NUM>. Preferably, the first lens group <NUM> may have an EFL of <NUM>.

The second lens group <NUM> includes a plurality of lenses. The second lens group <NUM> may include two or more lenses. When the second lens group <NUM> includes three or more lenses, a size and weight of the second lens group <NUM> may increase, and driving power may increase during movement. According to an embodiment, the second lens group <NUM> may include two lenses. The second lens group <NUM> may include a third lens and a fourth lens.

The second lens group <NUM> may include one filter. The filter may include an infrared (IR) filter. Accordingly, the filter may block near-infrared rays, for example, light having a wavelength of <NUM> to <NUM>, from light entering a camera module. An image sensor <NUM> may be connected to a printed circuit board through a wire. Alternatively, the filter may include a foreign material prevention filter and the IR filter sequentially disposed in the direction from the object to the image. When the filter includes the foreign material prevention filter, foreign materials generated while the second lens group <NUM> moves may be prevented from being introduced into the IR filter or the image sensor <NUM>.

The second lens group <NUM> may move in a direction parallel to an optical axis. That is, the plurality of lenses may move along a central axis of the lenses. A focus may be adjusted according to movement of the second lens group <NUM>. Accordingly, the second lens group <NUM> may serve as a focusing group.

The second lens group <NUM> may move from an infinity focus to a nearest focus. When the second lens group <NUM> moves from the infinity focus to the nearest focus, a distance between the first lens group <NUM> and the second lens group <NUM> may increase. The second lens group <NUM> may move from the nearest focus to the infinity focus. When the second lens group <NUM> moves from the nearest focus to the infinity focus, the distance between the first lens group <NUM> and the second lens group <NUM> may decrease.

The optical system according to the embodiment of the present invention may be a fixed zoom optical system of which a focus is adjusted according to the movement of the second lens group <NUM>. Accordingly, a magnification of the optical system may not increase or decrease according to the movement of the second lens group <NUM>.

According to an embodiment of the present invention, a movement stroke of the second lens group <NUM> may be less than <NUM>. Here, the movement stroke may be a distance by which the lens group may be moved by a driving unit. Thus, the second lens group <NUM> may move within <NUM> when moving from the infinity focus to the nearest focus. Since the movement stroke of the second lens group <NUM> is implemented within <NUM>, the driving unit for driving the second lens group <NUM> can be miniaturized. Accordingly, it is possible to miniaturize the camera module, and it is advantageous for the camera module to be mounted on a small electronic device such as a portable terminal.

The second lens group <NUM> may have negative refractive power. The second lens group <NUM> may have an effective focal length (EFL) in a range of greater than -<NUM> and less than -<NUM>. The second lens group <NUM> may have an EFL in a range of greater than -<NUM> and less than -<NUM>. Preferably, the second lens group <NUM> may have an EFL of -<NUM>.

The first lens group <NUM> and the second lens group <NUM> may move in a direction perpendicular to the optical axis. The first lens group <NUM> and the second lens group <NUM> may move in a direction parallel to a surface of the image sensor <NUM>. The first lens group <NUM> and the second lens group <NUM> may move integrally when moving in the direction perpendicular to the optical axis. The first lens group <NUM> and the second lens group <NUM> may implement an OIS while moving in the direction perpendicular to the optical axis.

According to an embodiment of the present invention, the optical system may have a total track length (TTL) that is less than <NUM>. Here, the TTL may be a distance from the surface of the image sensor to a first surface of the optical system. For example, the TTL may be a distance from a surface of the first lens group <NUM> closest to the object to an upper surface of the image sensor <NUM> on which light is incident. In the present specification, the TTL may be used interchangeably with a full-length distance. In the optical system according to the embodiment of the present invention, the TTL is fixed because, while the second lens group <NUM> disposed between the first lens group <NUM> and the image sensor <NUM> is moved in an optical axis direction, a focus is adjusted. According to an embodiment, in the optical system, the TTL may be fixed within <NUM>.

According to an embodiment of the present invention, the plurality of lenses included in the first lens group <NUM> and the second lens group <NUM> may be lenses to which a D-cut technique is applied. The plurality of lenses included in the first lens group <NUM> and the second lens group <NUM> may be D-cut lenses in which portions of upper and lower portions are cut. In this case, in the upper and lower portions of the plurality of lenses, ribs and portions of effective diameters may be cut, or only the ribs may be cut without the effective diameters being cut. According to an embodiment, the second lens group <NUM> may include a lens in which a value obtained by dividing a major axis length of an effective diameter by a minor axis length of the effective diameter is <NUM>. That is, the major axis length of the effective diameter may be the same as the minor axis length of the effective diameter. For example, in the case of the third lens <NUM>, the fourth lens <NUM>, and the fourth lens <NUM>, only ribs of upper and lower portions may be cut, and effective diameters thereof may not be cut. In the case of a circular type lens, there is a problem in that a volume of the lens is increased due to a height in a vertical direction, but as in the embodiment of the present invention, by applying a D-cut to the upper and lower portions of the plurality of lenses, a height in the vertical direction can be decreased, thereby reducing a volume of the lens.

Hereinafter, examples of various embodiments of the present invention will be described in more detail.

<FIG> is a cross-sectional view of the optical system at an infinity focus according to the first embodiment of the present invention. <FIG> is a cross-sectional view of the optical system at an intermediate focus according to the first embodiment of the present invention. <FIG> is a cross-sectional view of the optical system at a nearest focus according to the first embodiment of the present invention.

Referring to <FIG>, the optical system includes the first lens group <NUM> and the second lens group <NUM> sequentially arranged in a direction from an object toward an image. The first lens group <NUM> may include a first lens <NUM> and a second lens <NUM> sequentially arranged in the direction from the object to the image, and the second lens group <NUM> may include a third lens <NUM>, a fourth lens <NUM>, and a filter <NUM> sequentially arranged in the direction from the object toward the image.

Here, the first lens <NUM> may include a convex object side surface <NUM> and a concave image side surface <NUM>. The second lens <NUM> may include a concave object side surface <NUM> and a concave image side surface <NUM>.

The third lens <NUM> may include a convex object side surface <NUM> and a concave image side surface <NUM>. The fourth lens <NUM> may include a convex object side surface <NUM> and a concave image side surface <NUM>.

In <FIG>, when a distance between the first lens group <NUM> and the second lens group <NUM> is d1a and a distance between the second lens group <NUM> and the image sensor is d2a, the optical system may have an infinity focus. In <FIG>, when the distance between the first lens group <NUM> and the second lens group <NUM> is d1b and the distance between the second lens group <NUM> and the image sensor is d2b, the optical system may have an intermediate focus. For example, the optical system may have a focus at a distance of <NUM>. In <FIG>, when the distance between the first lens group <NUM> and the second lens group <NUM> is d1c and the distance between the second lens group <NUM> and the image sensor is d2c, the optical system may have a nearest focus. For example, the optical system may have a focus at a distance of <NUM>.

In the optical system, when the second lens group <NUM> moves from a position of <FIG> to a position of <FIG> through a position of <FIG>, the distance between the first lens group <NUM> and the second lens group <NUM> increases, and the distance between the second lens group <NUM> and the image sensor decreases. Therefore, a relationship of d1a<d2b<d2c and d2a>d2b>d2c can be established.

<FIG> shows graphs of a longitudinal spherical aberration, an astigmatic field curve, and a distortion of the optical system which are measured on light having wavelengths of <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> at an infinity focus according to the first embodiment. <FIG> shows graphs of a longitudinal spherical aberration, an astigmatic field curve, and a distortion of the optical system which are measured on light having wavelengths of <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> at an intermediate focus according to the first embodiment. <FIG> shows graphs of a longitudinal spherical aberration, an astigmatic field curve, and a distortion of the optical system which are measured on light having wavelengths of <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> at a nearest focus according to the first embodiment.

The longitudinal spherical aberration represents a longitudinal spherical aberration according to each wavelength, the astigmatic field curve represents the aberration characteristics of a tangential plane and a sagital plane according to a height of an image plane, and the distortion represents a degree of distortion according to the height of the image plane. Referring to <FIG>, it can be seen that the longitudinal spherical aberration is within a range of -<NUM> to <NUM> irrespective of wavelengths, it can be seen that the astigmatic field curve is within a range of -<NUM> to <NUM> irrespective of wavelengths, and it can be seen that the distortion is within a range of <NUM> to <NUM> irrespective of wavelength.

<FIG> illustrates an optical system according to a second embodiment of the present invention.

Referring to <FIG>, the optical system according to the embodiment of the present invention includes a first lens group <NUM>, a second lens group <NUM>, and a filter <NUM> sequentially arranged in a direction from an object toward an image. Here, the lens groups may correspond to the lens groups described above with reference to <FIG>.

According to an embodiment of the present invention, the first lens group <NUM> includes one lens. The first lens group <NUM> is fixed with respect to an image side. That is, the one lens may be fixed with respect to the image side. In this case, the first lens group <NUM> may include one or more lenses. When the first lens group <NUM> includes two or more lenses, an overall size of the optical system may increase. According to an embodiment, the first lens group <NUM> may include one lens. The first lens group <NUM> may include a first lens. The first lens group <NUM> may have positive refractive power.

The second lens group <NUM> includes a plurality of lenses. The second lens group <NUM> may include <NUM> or more lenses. When the second lens group <NUM> includes six or more lenses, a size and weight of the second lens group <NUM> may increase, and driving power may increase during movement. According to an embodiment, the second lens group <NUM> may include five lenses. The second lens group <NUM> may include a second lens <NUM>, a third lens <NUM>, a fourth lens <NUM>, a fifth lens <NUM>, and a sixth lens <NUM>.

The second lens group <NUM> may move from an infinity focus to a nearest focus. When the second lens group <NUM> moves from the infinity focus to the nearest focus, a distance between the first lens group <NUM> and a second lens group <NUM> may increase. The second lens group <NUM> may move from the nearest focus to the infinity focus. When the second lens group <NUM> moves from the nearest focus to the infinity focus, the distance between the first lens group <NUM> and the second lens group <NUM> may decrease.

According to an embodiment of the present invention, a movement stroke of the second lens group <NUM> may be less than <NUM>. Here, the movement stroke may be a distance by which the lens group may be moved by a driving unit. Thus, the second lens group <NUM> may move within <NUM> when moving from the infinity focus to the nearest focus. Since the movement stroke of the second lens group <NUM> is implemented within <NUM>, the driving unit for driving the second lens group <NUM> can be miniaturized. Accordingly, it is possible to miniaturize a camera module, and it is advantageous for the camera module to be mounted on a small electronic device such as a portable terminal. The second lens group <NUM> may have negative refractive power.

The optical system may include one filter <NUM>. The filter <NUM> may be fixed apart from a surface of a sensor by a certain interval. In an embodiment of the present invention, the filter <NUM> may be referred to as a third lens group. The filter <NUM> may include an IR filter. Accordingly, the filter <NUM> may block near-infrared rays, for example, light having a wavelength of <NUM> to <NUM>, from light entering the camera module. The image sensor <NUM> may be connected to a printed circuit board through a wire. Alternatively, the filter <NUM> may include a foreign material prevention filter and the IR filter sequentially arranged in the direction from the object toward the image. When the filter <NUM> includes the foreign material prevention filter, foreign materials generated while the second lens group <NUM> moves may be prevented from being introduced into the IR filter or an image sensor <NUM>.

The first lens group <NUM>, the second lens group <NUM>, and the filter <NUM> may move in a direction perpendicular to the optical axis. The first lens group <NUM>, the second lens group <NUM>, and the filter <NUM> may move in a direction parallel to a surface of the image sensor <NUM>. The first lens group <NUM>, the second lens group <NUM>, and the filter <NUM> may move integrally when moving in the direction perpendicular to the optical axis. The first lens group <NUM>, the second lens group <NUM>, and the filter <NUM> may implement an OIS while moving in the direction perpendicular to the optical axis.

According to an embodiment of the present invention, the optical system may have a TTL that is less than <NUM>. Here, The TTL may be a distance from the surface of the image sensor to a first surface of the optical system. For example, the TTL may be a distance from a surface of the first lens group <NUM> closest to the object to an upper surface of the image sensor <NUM> on which light is incident. In the present specification, the TTL may be used interchangeably with a full-length distance. In the optical system according to the embodiment of the present invention, the TTL is fixed because, while the second lens group <NUM> disposed between the first lens group <NUM> and the image sensor <NUM> is moved in an optical axis direction, a focus is adjusted. According to an embodiment, in the optical system, the TTL may be fixed within <NUM>.

According to an embodiment of the present invention, the plurality of lenses included in the first lens group <NUM> and the second lens group <NUM> may be lenses to which a D-cut technique is applied. The plurality of lenses included in the first lens group <NUM> and the second lens group <NUM> may be D-cut lenses in which portions of upper and lower portions are cut. In this case, in the upper and lower portions of the plurality of lenses, ribs and portions of effective diameters may be cut, or only the ribs may be cut without the effective diameter being cut. According to an embodiment, the second lens group <NUM> may include a lens in which a value obtained by dividing a major axis length of an effective diameter by a minor axis length of the effective diameter is <NUM>. That is, the major axis length of the effective diameter may be the same as the minor axis length of the effective diameter. For example, in the case of the third lens <NUM>, the fourth lens <NUM>, and the fourth lens <NUM>, only rubs of upper and lower portions may be cut, and effective diameters thereof may not be cut. In the case of a circular type lens, there is a problem in that a volume of the lens is increased due to a height in a vertical direction, but as in the embodiment of the present invention, by applying a D-cut to the upper and lower portions of the plurality of lenses, a height in the vertical direction can be decreased, thereby reducing a volume of the lens.

<FIG> is a cross-sectional view of the optical system at an infinity focus according to the second embodiment of the present invention. <FIG> is a cross-sectional view of the optical system at a nearest focus according to the second embodiment of the present invention.

Referring to <FIG> and <FIG>, the optical system includes the first lens group <NUM> and the second lens group <NUM> sequentially arranged in a direction from an object toward an image. The first lens group <NUM> includes a first lens <NUM> sequentially arranged in the direction from the object toward the image, and the second lens group <NUM> includes the second lens <NUM>, the third lens <NUM>, the fourth lens <NUM>, the fifth lens <NUM>, and the sixth lens <NUM> sequentially arranged in the direction from the object toward the image.

Here, the first lens <NUM> may include a convex object side surface <NUM> and a convex image side surface <NUM>.

The second lens <NUM> may include a concave object side surface <NUM> and a concave image side surface <NUM>. The third lens <NUM> may include a convex object side surface <NUM> and a concave image side surface <NUM>. The fourth lens <NUM> may include a concave object side surface <NUM> and a convex image side surface <NUM>. The fifth lens <NUM> may include a concave object side surface <NUM> and a concave image side surface <NUM>. The sixth lens <NUM> may include a convex object side surface <NUM> and a convex image side surface <NUM>.

In <FIG>, when a distance between the first lens group <NUM> and the second lens group <NUM> is d1a and a distance between the second lens group <NUM> and the image sensor is d2a, the optical system may have an infinity focus. In <FIG>, when the distance between the first lens group <NUM> and the second lens group <NUM> is d1b and the distance between the second lens group <NUM> and the image sensor is d2b, the optical system may have a nearest focus. For example, the optical system may have a focus at a distance of <NUM>.

In the optical system, when the second lens group <NUM> moves from a position of <FIG> to a position of <FIG>, the distance between the first lens group <NUM> and the second lens group <NUM> increases, and the distance between the second lens group <NUM> and the image sensor decreases. Therefore, a relationship of d1a<d2b and d2a>d2b can be established.

<FIG> shows graphs of a longitudinal spherical aberration, an astigmatic field curve, and a distortion of the optical system which are measured on light having wavelengths of <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> at an infinity focus according to the second embodiment. <FIG> shows graphs of a longitudinal spherical aberration, an astigmatic field curve, and a distortion of the optical system which are measured on light having wavelengths of <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> at a nearest focus according to the second embodiment.

The longitudinal spherical aberration represents a longitudinal spherical aberration according to each wavelength, the astigmatic field curve represents the aberration characteristics of a tangential plane and a sagital plane according to a height of an image plane, and the distortion represents a degree of distortion according to the height of the image plane. Referring to <FIG>, it can be seen that the longitudinal spherical aberration is within a range of -<NUM> to <NUM> irrespective of wavelength, it can be seen that the astigmatic field curve is within a range of -<NUM> to <NUM> irrespective of wavelengths, and it can be seen that the distortion is within a range of -<NUM> to <NUM> irrespective of wavelength.

Hereinafter, a configuration of a camera module <NUM> according to embodiments of the present invention will be described with reference to <FIG> and <FIG>. The camera module described below may correspond to the camera module described above with reference to <FIG>.

<FIG> is a schematic view illustrating a camera module according to an embodiment of the present invention. <FIG> is a schematic view illustrating a camera module according to another embodiment of the present invention.

Referring to <FIG> and <FIG>, a camera module <NUM> according to embodiments of the present invention may include a board <NUM>, a sensor <NUM>, a housing <NUM>, a first lens assembly <NUM>, a second lens assembly <NUM>, and a driving unit <NUM>. The camera module <NUM> may include a plurality of balls <NUM> and a cover <NUM>. The plurality of balls <NUM> may include first balls <NUM> and second balls <NUM>.

The sensor <NUM> may be disposed on the board <NUM>. The board <NUM> may be structurally coupled to the sensor <NUM>. The housing <NUM> may be disposed on the board <NUM>. The board <NUM> may be structurally coupled to the housing <NUM>. The cover <NUM> may be disposed on the board <NUM>. The board <NUM> may be structurally coupled to the cover <NUM>.

A circuit pattern may be disposed on the board <NUM>. Accordingly, the board <NUM> may be a printed circuit board <NUM>. The board <NUM> may be a flexible PCB (F-PCB), a PCB, or a board <NUM> in which a circuit is connectable. The circuit pattern disposed on the board <NUM> may electrically connect an external power supply for driving the sensor <NUM> to the sensor <NUM>. The circuit pattern disposed on the board <NUM> may electrically connect the driving unit <NUM> and a control element for controlling the driving unit <NUM>. In addition to the above example, the circuit pattern disposed on the board <NUM> may electrically connect various elements of the camera module <NUM>.

The sensor <NUM> may be an image sensor. The sensor <NUM> may be disposed on the board <NUM>. The sensor <NUM> may be disposed on an optical axis of the first lens assembly <NUM> and the second lens assembly <NUM>. The sensor <NUM> may perform a function of converting light, which passes through the first lens assembly <NUM> and the second lens assembly <NUM>, into image data.

The housing <NUM> may be disposed on the board <NUM>. The housing <NUM> may include an internal space.

The housing <NUM> may include a body part <NUM>, a moving part <NUM>, and a fixed part <NUM>.

The body part <NUM> may be coupled to the first lens assembly <NUM>. The body part <NUM> may move in a direction perpendicular to the optical axis. The body part <NUM> may move in a direction parallel to an upper surface of the sensor <NUM>.

The moving part <NUM> may be coupled to the second lens assembly <NUM>. The moving part <NUM> may be coupled to a second holder of the second lens assembly <NUM>. The moving part <NUM> may be coupled to the second lens assembly <NUM> to move integrally with the second lens assembly <NUM>. The moving part <NUM> may move in an optical axis direction. Accordingly, the moving part <NUM> may move the second lens assembly <NUM> in the optical axis direction.

The moving part <NUM> may be coupled to the body part <NUM>. The first ball <NUM> may be disposed between the moving part <NUM> and the body part <NUM>. The first ball <NUM> may support the moving part <NUM> to be movable in the optical axis direction. The plurality of first balls <NUM> may be provided. The first ball <NUM> may be rotatably accommodated in the moving part <NUM>. In this case, the moving part <NUM> may include a groove for accommodating the first ball <NUM>. In another embodiment, the first ball <NUM> may be movably accommodated in the body part <NUM>. In this case, the body part <NUM> may include a groove for accommodating the first ball <NUM>. The groove included in the moving part <NUM> or the body part <NUM> may be formed to accommodate one first ball <NUM>, but the present invention is not limited thereto. The ball may have a spherical shape.

The fixed part <NUM> may be fixedly disposed on an upper surface of the board <NUM>. The fixed part <NUM> may be coupled to the body part <NUM>. The fixed part <NUM> may include a support surface for supporting the body part <NUM>. The support surface may be a surface perpendicular to the optical axis. The support surface may be a surface parallel to the upper surface (or lower surface) of the board <NUM>. The body part <NUM> may be disposed on the support surface of the fixed part <NUM>. The second ball <NUM> may be disposed between the fixed part <NUM> and the body part <NUM>. The second ball <NUM> may support the body part <NUM> to be movable in the direction perpendicular to the optical axis. That is, the second ball <NUM> may support the body part <NUM> to be movable along the support surface of the fixed part <NUM>. The plurality of second balls <NUM> may be provided. The second ball <NUM> may be rotatably accommodated in the fixed part <NUM>. In this case, the fixed part <NUM> may include a groove for accommodating the second ball <NUM>. As another embodiment, the second ball <NUM> may be movably accommodated in the body part <NUM>. In this case, the body part <NUM> may include a groove for accommodating the second ball <NUM>. The groove included in the fixed part <NUM> or the body part <NUM> may be formed to accommodate one second ball <NUM>, but the present invention is not limited thereto. The ball may have a spherical shape.

The first lens assembly <NUM> may include a lens and a first holder for accommodating the lens. The second lens assembly <NUM> may include a lens and the second holder for accommodating the lens. The first lens assembly <NUM> and the second lens assembly <NUM> may correspond to the first lens group and the second lens group described above with reference to the drawings. Detailed descriptions thereof will be omitted.

The driving unit <NUM> may move the second lens assembly <NUM> in the optical axis direction. The driving unit <NUM> may move the moving part <NUM> included in the housing <NUM> in the optical axis direction. The driving unit <NUM> may move the second lens assembly <NUM> by moving the moving part <NUM> included in the housing <NUM> in the optical axis direction.

The driving unit <NUM> may move the housing <NUM> in the direction perpendicular to the optical axis. The driving unit <NUM> may move the body part <NUM> included in the housing <NUM> in the direction perpendicular to the optical axis. The driving unit <NUM> may move the first lens assembly <NUM> and the second lens assembly <NUM> by moving the body part <NUM> included in the housing <NUM> in the direction perpendicular to the optical axis.

The driving unit <NUM> may include a magnet <NUM>, a first coil <NUM>, and a second coil <NUM>.

The magnet <NUM> may be coupled to the housing <NUM>. The magnet <NUM> may be disposed in the housing <NUM>. The magnet <NUM> may be disposed on the body part <NUM> of the housing <NUM>. The magnet <NUM> may be coupled to the housing <NUM> to move integrally with the housing <NUM>. The magnet <NUM> may be coupled to the body part <NUM> of the housing <NUM> to move integrally with the body part <NUM>. The magnet <NUM> may be disposed to face the first coil <NUM>. The magnet <NUM> may face the first coil <NUM>. The magnet <NUM> may be disposed apart from the first coil <NUM>. The magnet <NUM> may be disposed to face the second coil <NUM>. The magnet <NUM> may face the second coil <NUM>. The magnet <NUM> may be disposed apart from the second coil <NUM>.

One or more magnets <NUM> may be provided. According to an embodiment, as shown in <FIG>, one magnet <NUM> may be provided. The one magnet <NUM> may be disposed to face the corresponding first and second coils <NUM> and <NUM>. In this case, one first coil <NUM> and one second coil <NUM> may be provided. According to another embodiment, as shown in <FIG>, two magnets <NUM> may be provided. The two magnets <NUM> may be disposed to face each other with respect to the optical axis. In this case, two first coils <NUM> may be provided, and two second coils <NUM> may be provided. One first coil <NUM> and one second coil <NUM> may be disposed to correspond to one magnet <NUM>. In addition, three or more magnets <NUM> may be provided.

The magnet <NUM> may be fixed to the housing <NUM> through an adhesive. In addition, the magnet <NUM> may be coupled to the housing <NUM> through various fixing methods.

The first coil <NUM> may be coupled to at least one side of the second lens assembly <NUM>. The first coil <NUM> may be disposed on an outer surface of the second lens assembly <NUM>. The first coil <NUM> may be disposed on the second holder included in the second lens assembly <NUM>. The first coil <NUM> may be disposed on an outer surface of the second holder included in the second lens assembly <NUM>. The first coil <NUM> may be disposed to face the magnet <NUM>. The first coil <NUM> may be disposed on the second lens assembly <NUM> to face the magnet <NUM>.

The first coil <NUM> may be formed as a pattern coil on the outer surface of the second lens assembly <NUM>. The first coil <NUM> may be a fine pattern coil formed integrally with the outer surface of the second lens assembly <NUM>. When a current is applied to the first coil <NUM>, the first coil <NUM> may electromagnetically interact with the magnet <NUM>. According to an embodiment, when a current is applied to the first coil <NUM>, the second lens assembly <NUM> coupled to the first coil <NUM> may move away from the sensor <NUM> in the optical axis direction. That is, the camera module <NUM> may implement an AF function by applying a current to the first coil <NUM>. The first coil <NUM> may perform a function of an AF coil.

One or more first coils <NUM> may be provided. According to an embodiment, as shown in <FIG>, one first coil <NUM> may be provided. The one coil may be disposed on the outer surface of the second lens assembly <NUM>. According to another embodiment, as shown in <FIG>, two first coils <NUM> may be provided. The two first coils <NUM> may be disposed to face each other with respect to the optical axis. In addition, three or more first coils <NUM> may be provided.

The second coil <NUM> may be coupled to at least one side of the housing <NUM>. The second coil <NUM> may be disposed on the fixed part <NUM> of the housing <NUM>. The second coil <NUM> may be disposed to face the magnet <NUM>. The second coil <NUM> may be disposed on the fixed part <NUM> of the housing <NUM> to face the magnet <NUM>.

The second coil <NUM> may be formed as a pattern coil on the fixed part <NUM> of the housing <NUM>. The second coil <NUM> may be a fine pattern coil formed integrally with the fixed part <NUM> of the housing <NUM>. When a current is applied to the second coil <NUM>, the second coil <NUM> may electromagnetically interact with the magnet <NUM>. According to an embodiment, when a current is applied to the second coil <NUM>, the magnet <NUM> electromagnetically interacting with the second coil <NUM> may move. Since the magnet <NUM> is coupled to the body part <NUM> of the housing <NUM>, the body part <NUM> of the housing <NUM> may be moved through an electromagnetic interaction between the second coil <NUM> and the magnet <NUM>. Since the body part <NUM> of the housing <NUM> is coupled to the first lens assembly <NUM> and coupled to the second lens assembly <NUM> through the moving part <NUM>, an electromagnetic interaction between the second coil <NUM> and the magnet <NUM> may move the first lens assembly <NUM> and the second lens assembly <NUM> in the direction perpendicular to the optical axis. Thus, the camera module <NUM> may perform an OIS function (hand shake correcting function). The second coil <NUM> may perform a function of an OIS coil.

One or more second coils <NUM> may be provided. According to an embodiment, as shown in <FIG>, one second coil <NUM> may be provided. The one second coil <NUM> may be disposed on the fixed part <NUM> of the housing <NUM>. According to another embodiment, as shown in <FIG>, two first coils <NUM> may be provided. The two second coils <NUM> may be disposed on the fixed part <NUM> of the housing <NUM> to face each other with respect to the optical axis. In addition, three or more second coils <NUM> may be provided.

The cover <NUM> may be disposed on the housing <NUM>. The cover <NUM> may have an opening such that a portion of the housing <NUM> to which the lens assembly is coupled is exposed. The opening of the cover <NUM> may be provided apart from a portion of the housing <NUM>. For example, a diameter of the opening may be greater than a diameter of a portion of the housing <NUM> exposed through the opening. This is to provide a space in which the housing <NUM> moves in the direction perpendicular to the optical axis.

The cover <NUM> may include a metal material. The cover <NUM> may be formed as a ferrite plate. The cover <NUM> may prevent internal electromagnetic waves from being emitted to the outside or may prevent external electromagnetic waves from being introduced therein.

Accordingly, the cover <NUM> is referred to as a "shield can" and may perform an electromagnetic wave shielding function. However, the material of the cover <NUM> is not limited thereto. The cover <NUM> may include a plastic material. In this case, the cover <NUM> may not perform an electromagnetic wave shielding function.

<FIG> shows views for describing an operation of a driving unit according to an embodiment of the present invention.

Referring to <FIG>, a camera module <NUM> according to the embodiment of the present invention may include a board <NUM>, a sensor <NUM>, a first lens assembly <NUM>, and a second lens assembly <NUM>.

As shown <FIG>, a driving unit <NUM> may move the second lens assembly <NUM> in an optical axis direction through an electromagnetic interaction between a first coil <NUM> and a magnet <NUM>. Thus, the camera module <NUM> may perform an AF function. Even when the second lens assembly <NUM> is moved in the optical axis direction as the AF function is performed, the first lens assembly <NUM> is not moved in the optical axis direction. The first lens assembly <NUM> is fixed at a certain distance from the sensor <NUM> (and the board <NUM>). When the AF function is performed, since the first lens assembly <NUM> is fixed, a TTL of the camera module <NUM> may be fixed. Meanwhile, a collision prevention member may be disposed between the first lens assembly <NUM> and the second lens assembly <NUM>. The collision prevention member may prevent a lens from being damaged by the second lens assembly <NUM> colliding with the first lens assembly <NUM> while moving in the optical axis direction when the AF function is performed. Other than that the AF function is performed, the collision prevention member may prevent the lens from being damaged by the first lens assembly <NUM> and the second lens assembly <NUM> colliding with each other due to an external impact.

As shown in <FIG>, the driving unit <NUM> may move a body part <NUM> of a housing <NUM> in a direction perpendicular to an optical axis through an electromagnetic interaction between a second coil <NUM> and a magnet <NUM>. Since the first lens assembly <NUM> and the second lens assembly <NUM> are coupled to the body part <NUM>, the electromagnetic interaction between the second coil <NUM> and the magnet <NUM> may integrally move the first lens assembly <NUM> and the second lens assembly <NUM> in the direction perpendicular to the optical axis. Thus, the camera module <NUM> may perform an OIS function.

<FIG> shows views for describing an operation of a driving unit according to another embodiment of the present invention.

Referring to <FIG>, a camera module <NUM> according to the embodiment of the present invention may include a board <NUM>, a sensor <NUM>, a first lens assembly <NUM>, a second lens assembly <NUM>, and a third lens assembly <NUM>. Here, the third lens assembly <NUM> may be a filter.

As shown <FIG>, a driving unit <NUM> may move the second lens assembly <NUM> in an optical axis direction through an electromagnetic interaction between a first coil <NUM> and a magnet <NUM>. Thus, the camera module <NUM> may perform an AF function. Even when the second lens assembly <NUM> is moved in the optical axis direction as the AF function is performed, the first lens assembly <NUM> and the third lens assembly <NUM> are not moved in the optical axis direction. The first lens assembly <NUM> and the third lens assembly <NUM> are fixed at a certain distance from the sensor <NUM> (and the board <NUM>). When the AF function is performed, since the first lens assembly <NUM> is fixed, a TTL of the camera module <NUM> may be fixed. Meanwhile, a collision prevention member may be disposed between the first lens assembly <NUM> and the second lens assembly <NUM> and between the second lens assembly <NUM> and the third lens assembly <NUM>. The collision prevention member may prevent a lens from being damaged by the second lens assembly <NUM> colliding with the first lens assembly <NUM> and the third lens assembly <NUM> while moving in the optical axis direction when the AF function is performed. Other than that the AF function is performed, the collision prevention member may prevent the lens from being damaged by the first lens assembly <NUM> and the second lens assembly <NUM> colliding with each other due to an external impact and the second lens assembly <NUM> and the third lens assembly <NUM> colliding with each other due to an external impact.

As shown in <FIG>, the driving unit <NUM> may move a body part <NUM> of a housing <NUM> in a direction perpendicular to an optical axis through an electromagnetic interaction between a second coil <NUM> and the magnet <NUM>. Since the first lens assembly <NUM>, the second lens assembly <NUM>, and the third lens assembly <NUM> are coupled to the body part <NUM>, the electromagnetic interaction between the second coil <NUM> and the magnet <NUM> may integrally move the first lens assembly <NUM>, the second lens assembly <NUM>, and the third lens assembly <NUM> in the direction perpendicular to the optical axis. Thus, the camera module <NUM> may perform an OIS function.

<FIG> shows views for describing a structure of a housing according to an embodiment of the present invention. <FIG> shows views for describing a structure of a housing according to another embodiment of the present invention.

A housing <NUM> shown in <FIG> may be a body part <NUM> of the housing <NUM>. According to an embodiment, as shown in <FIG>, the body part <NUM> of the housing <NUM> may be integrally formed. The integrally formed body part <NUM> of the housing <NUM> may be coupled to a moving part <NUM> coupled to a first lens assembly <NUM> and a second lens assembly <NUM>. The second lens assembly <NUM> may move in an optical axis in an accommodating space inside the integrally formed body part <NUM> of the housing <NUM> through a driving unit <NUM>.

According to another embodiment, as shown in <FIG>, the body part <NUM> of the housing <NUM> may include a first body part <NUM> and a second body part <NUM>. The first body part <NUM> may be coupled to the first lens assembly <NUM>. The second body part <NUM> may be coupled to the moving part <NUM> coupled to the second lens assembly <NUM>. The second lens assembly <NUM> may move in the optical axis in the accommodating space inside the second body part <NUM> through the driving unit <NUM>. The first body part <NUM> and the second body part <NUM> may be provided separately. The first body part <NUM> and the second body part <NUM> may be formed to be structurally coupled. A collision prevention member for preventing collision between the first lens assembly <NUM> and the second lens assembly <NUM> may be formed integrally with a portion of the second body part <NUM> coupled to the first body part <NUM>.

Claim 1:
A camera device (<NUM>) comprising:
a base (<NUM>);
a first lens assembly (<NUM>) which is disposed in the base and includes a first lens group (<NUM>) and a first lens support unit (<NUM>) to which the first lens group is fixed;
a second lens assembly (<NUM>) which is disposed in the base and includes a second lens group (<NUM>) and a second lens support unit (<NUM>) to which the second lens group is fixed; and
a driving unit (<NUM>) configured to drive the second lens support unit (<NUM>),
wherein:
a first stopper member (<NUM>) and a second stopper member (<NUM>) are formed on an inner wall of the second lens support unit (<NUM>) and spaced apart from each other by an interval greater than a height of the first lens assembly (<NUM>) in a moving direction of the second lens support unit (<NUM>);
the first lens support unit (<NUM>) is accommodated between the first stopper (<NUM>) member and the second stopper member (<NUM>) in the second lens support unit (<NUM>); and
the second lens assembly (<NUM>) is configured to move together with the first lens support unit (<NUM>) and the first lens assembly i(<NUM>) in the second lens support unit (<NUM>) along the base (<NUM>).