Patent Description:
The invention relates to a lens moving apparatus according to claim <NUM> and a camera module comprising such a lens and a lens moving apparatus. More particularly, the invention relates to a lens moving apparatus which improves space efficiency of a bobbin and performs feedback of the displacement of a lens in the optical axis direction to shorten a focus alignment time of the lens.

<CIT> discloses a lens moving apparatus according to the preamble of claim <NUM>.

Recently, development of IT products, such as cellular phones, smartphones, tablet PCs, notebooks, etc., having micro digital cameras installed therein, is underway.

In an IT product having a conventional micro digital camera installed therein, a lens moving apparatus aligning the focal distance of a lens by adjusting an interval between an image sensor converting external light into a digital image or a digital moving picture and the lens is provided.

However, in order to perform an auto-focusing function, the conventional micro digital camera requires a long auto-focusing time.

It is an object of the invention to provide a lens moving apparatus, which improves space efficiency of a bobbin and which performs feedback of the displacement of a lens in the optical axis direction to shorten a focus alignment time of the lens.

This technical problem is solved e.g. by the lens moving apparatus of independent claim <NUM>.

Embodiments provide a lens moving apparatus which may shorten an auto-focusing time of a lens.

Embodiments provide a lens moving apparatus which may more accurately and rapidly locate a lens at a focal distance of the lens.

Embodiments provide a lens moving apparatus which may improve an auto-focusing function and have enhanced space efficiency and durability.

Arrangements and embodiments may be described in detail with reference to the following drawings in which like reference numerals refer to like elements and wherein:.

Hereinafter, embodiments will be described with reference to the annexed drawings. In the drawings, the same or similar elements are denoted by the same reference numerals even though they are depicted in different drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the disclosure rather unclear. Those skilled in the art will appreciate that some features in the drawings are exaggerated, reduced, or simplified for ease in description, and drawings and elements thereof are not shown always at the proper rate.

For reference, in the respective drawings, a rectangular coordinate system (x, y, z) may be used. In the drawings, the x-axis and the y-axis mean a plane perpendicular to an optical axis and, for convenience, an optical axis (z-axis) direction may be referred to as a first direction, an x-axis direction may be referred to as a second direction, and a y-axis direction may be referred to as a third direction.

<FIG> is a schematic perspective view of a lens moving apparatus <NUM> in accordance with one embodiment, <FIG> is a schematic exploded perspective view of the lens moving apparatus <NUM> in accordance with the embodiment, <FIG> is a schematic perspective view of the lens moving apparatus <NUM> of <FIG>, from which a cover member <NUM> is removed, <FIG> is a schematic plan view of <FIG>, <FIG> is a schematic perspective view of a housing <NUM> in accordance with the embodiment, <FIG> is a schematic perspective view of the housing <NUM>, as seen from an angle differing from the angle of <FIG>, <FIG> is a schematic perspective bottom view of the housing <NUM> in accordance with the embodiment, <FIG> is a schematic exploded perspective view of the housing <NUM> in accordance with the embodiment, <FIG> is a schematic plan view of an upper elastic member <NUM> in accordance with the embodiment, and <FIG> is a schematic plan view of a lower elastic member <NUM> in accordance with the embodiment.

The lens moving apparatus <NUM> in accordance with this embodiment is an apparatus which locates an image sensor at the focal distance of a lens by adjusting a distance between the lens and the image sensor in a camera module. That is, the lens moving apparatus <NUM> is an apparatus performing an auto-focusing function.

As exemplarily shown in <FIG>, the lens moving apparatus <NUM> in accordance with this embodiment includes a cover member <NUM>, an upper elastic member <NUM>, a bobbin <NUM>, a coil <NUM> provided on the bobbin <NUM>, a housing <NUM>, driving magnets <NUM> and a printed circuit board <NUM> provided on the housing <NUM>, a lower elastic member <NUM>, a base <NUM>, a sensing unit sensing a movement of the bobbin <NUM> in the optical axis direction (i.e., the first direction), and magnetic bodies <NUM> mounted on the driving magnets <NUM>.

The cover member <NUM> may have a box shape and be combined with the upper portion of the base <NUM>. In a reception space formed by the cover member <NUM> and the base <NUM>, the upper elastic member <NUM>, the bobbin <NUM>, the coil <NUM> provided on the bobbin <NUM>, the housing <NUM>, and the driving magnets <NUM> and the printed circuit board <NUM> provided on the housing <NUM> are received.

The cover member <NUM> is provided with an opening formed on the upper surface thereof to expose a lens combined with the bobbin <NUM> to external light. Further, a window formed of a light transmitting material is provided on the opening. The window prevents foreign substances, such as dust or moisture, from being introduced into a camera module.

The cover member <NUM> may include first grooves <NUM> formed at the lower portion thereof. Although this will be described later, the base <NUM> may include second grooves <NUM> at regions contacting the first grooves <NUM> (i.e., a positions corresponding to the first grooves <NUM>) when the cover member <NUM> and the base <NUM> are combined. When the cover member <NUM> and the base <NUM> are combined, recesses having a designated area may be formed through combination of the first grooves <NUM> and the second grooves <NUM>. An adhesive member having viscosity may be applied to the recesses. That is, the adhesive member applied to the recesses fills gaps between opposite surfaces of the cover member <NUM> and the base <NUM> through the recesses and may seal a space between the cover member <NUM> and the base <NUM> and close the side surfaces of the cover member <NUM> and the base <NUM> when the cover <NUM> and the base <NUM> are combined.

Further, a third groove <NUM> may be formed on a surface of the cover member <NUM> corresponding to a terminal surface of the printed circuit board <NUM> so as to prevent interference between the cover member <NUM> and a plurality of terminals formed on the terminal surface. The third groove <NUM> may be formed on the entirety of the surface of the cover member <NUM> opposite the terminal surface, and the adhesive member may be applied to the inside of the third groove <NUM> to seal the cover member <NUM>, the base <NUM>, and the printed circuit board <NUM> and to close the side surfaces of the cover member <NUM> and the base <NUM> when the cover <NUM> and the base <NUM> are combined.

Although the first grooves <NUM>, the second grooves <NUM>, and the third groove <NUM> are formed on the cover member <NUM> and the base <NUM>, the disclosure is not limited thereto but the first grooves <NUM>, the second grooves <NUM>, and the third groove <NUM> having similar shapes to the above shapes may be formed on the base <NUM> only or formed on the cover member <NUM> only.

The base <NUM> may be formed in a rectangular shape and be combined with the cover member <NUM> to form the reception space for the bobbin <NUM> and the housing <NUM>.

A stepped part protruding to a designated thickness in the outward direction may be provided so as to surround the lower edge of the base <NUM>. The designated thickness of the stepped part is the same as the thickness of the side surface of the cover member <NUM> and, when the cover member <NUM> is combined with the base <NUM>, the side surface of the cover member <NUM> may be loaded on, contact, be disposed on, or be combined with the upper surface or side surface of the stepped part. Thereby, the base <NUM> may guide the cover member <NUM> combined with the upper portion of the stepped part, and the end of the cover member <NUM> may be in surface-contact with the stepped part and include the lower surface or the side surface. The stepped part and the end of the cover member <NUM> may be fixed to each other and sealed by an adhesive agent, etc..

The second grooves <NUM> may be formed on the stepped part at positions corresponding to the first grooves <NUM> of the cover member <NUM>. As described above, the second grooves <NUM> may be combined with the first grooves <NUM> of the cover member <NUM> and thus form the recesses, i.e., spaces filled with the adhesive member.

The base <NUM> may include an opening formed at the central region thereof. The opening may be formed at a position corresponding to the position of the image sensor disposed on the camera module.

Further, the base <NUM> may include four guide members <NUM> protruding perpendicularly from four corners to a designated height in the upward direction. The guide members <NUM> may have a polyprism shape. The guide members <NUM> may be inserted into, fastened to, or combined with lower guide grooves <NUM> of the housing <NUM> which will be described later. Due to the guide members <NUM> and the lower guide grooves <NUM>, when the housing <NUM> is loaded or disposed on the base <NUM>, the combined position of the housing <NUM> on the base <NUM> may be guided and separation of the housing <NUM> from a reference position where the housing <NUM> needs to be mounted, caused by vibration during the operating process of the lens moving apparatus <NUM> or worker's mistake during the combination process, may be prevented.

As exemplarily shown in <FIG>, the housing <NUM> may have a column shape with a hollow formed therein (for example, a rectangular prism shape with a hollow). The housing <NUM> is configured so as to support at least two driving magnets <NUM> and the printed circuit board <NUM> and receive the bobbin <NUM> such that the bobbin <NUM> in the housing <NUM> may move in the first direction against the housing <NUM>.

The housing <NUM> may include four flat side surfaces <NUM>. The side surfaces <NUM> of the housing <NUM> may have an area which is equal to or greater than the area of the driving magnets <NUM>.

As exemplarily shown in <FIG>, a magnet through hole 141a or recess in which the driving magnet <NUM> is loaded or disposed may be provided on each of two side surfaces opposite each other, among the four side surfaces <NUM> of the housing <NUM>.

The magnet through holes 141a or recesses may have a size and a shape corresponding to those of the driving magnets <NUM> or have a shape to guide the driving magnets <NUM>. A first driving magnet <NUM> and a second driving magnet <NUM>, i.e., two driving magnets <NUM>, may be mounted on the magnet through holes 141a.

Further, a sensor through hole 141b into, in, to, or on which a position sensor <NUM>, which will be described later, is inserted, disposed, fixed, or loaded may be provided on one side surface <NUM> perpendicular to the two side surfaces <NUM> or other side surfaces <NUM> than the two side surfaces <NUM>, among the four side surfaces <NUM> of the housing <NUM>. The sensor through hole 141b may have a size and a shape corresponding to those of the position sensor <NUM>, which will be described later. Further, at least one mounting protrusion <NUM> for mounting, disposition, temporary fixing, or fixing of the printed circuit board <NUM> may be provided on the side surface <NUM>. The mounting protrusion <NUM> may be inserted into a mounting through hole <NUM> formed on the printed circuit board <NUM>, which will be described later. Here, the mounting through hole <NUM> and the mounting protrusion <NUM> may be combined with each other by a shape fitting method or an interference fitting method. However, the mounting through hole <NUM> and the mounting protrusion <NUM> may have a simple guide function.

Among the four side surfaces <NUM> of the housing <NUM>, the other side surface <NUM> opposite to the above side surface <NUM> may be a flat surface but is not limited thereto.

In accordance with another embodiment, first and second magnet through holes 141a and 141a' on or to which the driving magnets <NUM> are located, disposed, or fixed may be provided on two side surfaces opposite each other, among the four side surfaces <NUM> of the housing <NUM>. Further, a third magnet through hole and a sensor through hole 141b separated from the third magnet through hole by a designated distance may be provided on one side surface <NUM> perpendicular to the two side surfaces <NUM> or other side surfaces <NUM> than the two side surfaces <NUM>, among the four side surfaces <NUM> of the housing <NUM>. Moreover, a fourth magnet through hole may be provided on the other side surface <NUM> opposite to the side surface <NUM> among the four side surfaces <NUM> of the housing <NUM>.

That is, four magnet through holes and one sensor through hole 141b may be provided on the four side surfaces <NUM> of the housing <NUM>.

The first magnet through hole 141a and the second magnet through hole 141a' have the same size and the same shape, and have a length in the sideward direction which is (almost) the same as the length of the side surfaces <NUM> of the housing <NUM> in the sideward direction. On the other hand, the third magnet through hole and the fourth magnet through hole have the same size and the same shape, and may have a length in the sideward direction which is smaller than that of the first magnet through hole 141a and the second magnet through hole 141a'. Since the sensor through hole 141b is formed on the side surface on which the third magnet through hole is formed, such a structure serves to secure a space for the sensor through hole 141b.

Of course, the first driving magnet <NUM> to the fourth driving magnet may be located on, disposed in, or fixed to the first magnet through hole to the fourth magnet through hole. In the same manner, the first driving magnet <NUM> and the second driving magnet <NUM> have the same size and the same shape, and have a length in the sideward direction which is (almost) the same as the length of the side surfaces <NUM> of the housing <NUM> in the sideward direction. Further, the third driving magnet and the fourth driving magnet have the same size and the same shape, and may have a length in the sideward direction which is smaller than that of the first driving magnet <NUM> and the second driving magnet <NUM>.

The third magnet through hole and the fourth magnet through hole may be symmetrically disposed on a straight line with respect to the center of the housing <NUM>. That is, the third driving magnet <NUM> and the fourth driving magnet may be symmetrically disposed on a straight line with respect to the center of the housing <NUM>. If the third driving magnet <NUM> and the fourth driving magnet <NUM> opposite to each other are disposed eccentrically at one side regardless of the center of the housing <NUM>, electromagnetic force applied to the coil <NUM> of the bobbin <NUM> is biased to the side and thus, the bobbin <NUM> may be tilted. That is, by symmetrically disposing the third driving magnet <NUM> and the fourth driving magnet on a straight line with respect to the center of the housing <NUM>, electromagnetic force which is not eccentric may be applied to the bobbin <NUM> and the coil <NUM> and thus, movement of the bobbin <NUM> in the first direction may be easily and accurately guided.

Further, as exemplarily shown in <FIG> and <FIG>, a plurality of first stoppers <NUM> may protrude from the upper surface of the housing <NUM>. The first stoppers <NUM> serve to prevent collision between the cover member <NUM> and the body of the housing <NUM>, and prevent the upper surface of the housing <NUM> from colliding directly with the upper inner surface of the cover member <NUM> when external impact is applied. Further, the first stoppers <NUM> may serve to guide the installed position of the upper elastic member <NUM>. For this purpose, as exemplarily shown in <FIG>, guide grooves <NUM> having a shape corresponding to the first stoppers <NUM> may be formed at positions of the upper elastic member <NUM> corresponding to the first stoppers <NUM>.

Further, a plurality of upper frame support protrusions <NUM> with which an outer frame <NUM> of the upper elastic member <NUM> is combined may protrude from the upper surface of the housing <NUM>. Although this will be described later, first through holes 152a or recesses having a shape corresponding to the upper frame support protrusions <NUM> may be formed at positions of the outer frame <NUM> of the upper elastic member <NUM> corresponding to the upper frame support protrusions <NUM>. The upper frame support protrusions <NUM> may be fixed to the first through holes 152a using an adhesive agent or by fusion and fusion may include thermal fusion or ultrasonic fusion.

Further, as exemplarily shown in <FIG>, a plurality of lower frame support protrusions <NUM> with which an outer frame <NUM> of the lower elastic member <NUM> is combined may protrude from the lower surface of the housing <NUM>. Insertion recesses 162a or holes having a shape corresponding to the lower frame support protrusions <NUM> may be formed at positions of the outer frame <NUM> of the lower elastic member <NUM> corresponding to the lower frame support protrusions <NUM>. The lower frame support protrusions <NUM> may be fixed to the insertion recesses 162a using an adhesive agent or by fusion and fusion may include thermal fusion or ultrasonic fusion.

The driving magnets <NUM> may be fixed to the magnet through holes 141a using an adhesive agent, without being limited thereto. That is, the driving magnets <NUM> may be fixed to the magnet through holes 141a using adhesive members, such as a double-sided tape. Further, in accordance with a modified embodiment, in place of the magnet through holes 141a, recess-shaped magnet loading parts may be formed on the inner surface of the housing <NUM> and the magnet loading parts may have a size and a shape corresponding to the size and the shape of the driving magnets <NUM>.

The driving magnets <NUM> may be installed at positions corresponding to the coil <NUM> provided on the bobbin <NUM>. Further, the driving magnet <NUM> may be formed in one body. In this embodiment, the driving magnet <NUM> may be configured such that the north (N) pole is formed on the surface of the driving magnet <NUM> opposite the coil <NUM> of the bobbin <NUM> and the south (S) pole is formed on the other surface of the driving magnet <NUM>. However, the disclosure is not limited thereto and the driving magnet <NUM> may be configured such that the N pole and the S pole are reversed. Further, the driving magnet <NUM> may be split into two sections along the plane vertical to the optical axis.

The driving magnet <NUM> may have a rectangular parallelepiped structure having a designated width and be loaded in the magnet through hole 141a or recess so that the wide surface of the driving magnet <NUM> may form a part of the side surface <NUM> of the housing <NUM>. Here, the opposite driving magnets <NUM> may be installed in parallel. Further, the driving magnets <NUM> may be disposed opposite the coil <NUM> of the bobbin <NUM>. The opposite surfaces of the driving magnet <NUM> and the coil <NUM> of the bobbin <NUM> may be disposed in parallel, without being limited thereto. That is, according to design, only one of the opposite surfaces of the driving magnet <NUM> and the coil <NUM> of the bobbin <NUM> may be a flat surface and the other may be a curved surface. Otherwise, both of the opposite surfaces of the driving magnet <NUM> and the coil <NUM> of the bobbin <NUM> may be curved surfaces and, in this case, the opposite surfaces of the driving magnet <NUM> and the coil <NUM> of the bobbin <NUM> may have the same curvature.

As described above, the sensor through hole 141b or recess is provided on one side surface <NUM> of the housing <NUM>, and the position sensor <NUM> is inserted into, disposed in, or loaded in the sensor through hole 141b and electrically connected to one surface of the printed circuit board <NUM> by soldering. That is, the printed circuit board <NUM> may be fixed to, supported by, or disposed on the outer surface of one side surface <NUM> with the sensor through hole 141b or recess among the four side surfaces <NUM> of the housing <NUM>.

The position sensor <NUM> and a sensing magnet <NUM> of the bobbin <NUM>, which will be described later, forms a sensing unit to judge a first displacement value of the bobbin <NUM> in the first direction. For this purpose, the position sensor and the sensor through hole 141b or recess are disposed at a position corresponding to the position of the sensing magnet <NUM>.

The position sensor <NUM> may be a sensor sensing change of magnetic force emitted from the sensing magnet <NUM> of the bobbin <NUM>. Further, the position sensor <NUM> may be a Hall sensor. However, the position sensor <NUM> is not limited thereto and any sensor which may sense change of magnetic force or any sensor which may sense a position instead of magnetic force, for example, a photoreflector, may be used.

The printed circuit board <NUM> is combined with or disposed on one side surface <NUM> of the housing <NUM> and may include the mounting through hole <NUM> or recess, as described above. Thus, the installed position of the printed circuit board <NUM> may be guided by the mounting protrusion <NUM> provided on the side surface <NUM> of the housing <NUM>.

Further, a plurality of terminals <NUM> is disposed on the printed circuit board <NUM>. The terminals <NUM> may receive external power and supply current to the coil <NUM> of the bobbin <NUM> and the position sensor <NUM>. The number of the terminals <NUM> formed on the printed circuit board <NUM> may be increased or decreased according to kinds of components which need to be controlled. In accordance with this embodiment, the printed circuit board <NUM> may be an FPCB.

The printed circuit board <NUM> may include a controller readjusting the amount of current applied to the coil <NUM> based on the first displacement value sensed by the sensing unit.

The controller is mounted on the printed circuit board <NUM>.

Further, in accordance with another embodiment, a controller is not mounted on the printed circuit board <NUM> and may be mounted on another substrate and such a substrate may be a substrate on which the image sensor of the camera module is mounted or another separate substrate.

Calibration of an actuator driving distance may be additionally carried out based on a Hall voltage difference to change of a magnetic flux density detected by the Hall sensor.

The bobbin <NUM> may be configured so as to reciprocate in the first axis direction with respect to the housing <NUM> fixed in the first axis direction. An auto-focusing function may be executed by movement of the bobbin <NUM> in the first axis direction.

The bobbin <NUM> will be described in more detail later with reference to the accompanying drawings.

The upper elastic member <NUM> and the lower elastic member <NUM> may elastically support the ascending and/or descending operation of the bobbin <NUM> in the optical axis direction. Plate springs may be used as the upper elastic member <NUM> and the lower elastic member <NUM>.

As exemplarily shown in <FIG> and <FIG> and <FIG>, the upper elastic member <NUM> and the lower elastic member <NUM> may include inner frames <NUM> and <NUM> combined with the bobbin <NUM>, outer frames <NUM> and <NUM> combined with the housing <NUM>, and connection parts <NUM> and <NUM> connecting the inner frames <NUM> and <NUM> and the outer frames <NUM> and <NUM>.

The connection parts <NUM> and <NUM> may be bent at least one time and form a pattern with a designated shape. The ascending and/or descending operation of the bobbin <NUM> in the optical axis direction, i.e., the first direction, may be elastically (flexibly) supported through position change and fine deformation of the connection parts <NUM> and <NUM>.

In accordance with this embodiment, as exemplarily shown in <FIG>, the upper elastic member <NUM> may include a plurality of first through holes 152a formed on the outer frame <NUM> and a plurality of second through holes 151a formed on the inner frame <NUM>.

The first through holes 152a may be combined with the upper frame support protrusions <NUM> provided on the upper surface of the housing <NUM>, and the second through holes 151a or recesses may be combined with upper support protrusions <NUM> provided on the upper surface of the bobbin <NUM>, which will be described later. That is, the outer frame <NUM> may be fixed to and combined with the housing <NUM> through the first through hole 152a and the inner frame <NUM> may be fixed to and combined with the bobbin <NUM> through the second through holes 151a or recesses.

The connection parts <NUM> may connect the inner frame <NUM> and the outer frame <NUM> so that the inner frame <NUM> may be elastically deformed within a designated range in the first direction with respect to the outer frame <NUM>.

At least one of the inner frame <NUM> and the outer frame <NUM> of the upper elastic member <NUM> may include at least one terminal part elastically connected to at least one of the coil <NUM> of the bobbin <NUM> and the printed circuit board <NUM>.

As exemplarily shown in <FIG>, the lower elastic member <NUM> may include a plurality of insertion recesses 162a or holes formed on the outer frame <NUM> and a plurality of third through holes 161a or recesses formed on the inner frame <NUM>.

The insertion recesses 162a or holes may be combined with the lower frame support protrusions <NUM> provided on the lower surface of the housing <NUM>, and the third through holes 161a or recesses may be combined with lower support protrusions <NUM> provided on the lower surface of the bobbin <NUM>, which will be described later. That is, the outer frame <NUM> may be fixed to and combined with the housing <NUM> through the insertion recesses 162a or holes and the inner frame <NUM> may be fixed to and combined with the bobbin <NUM> through the third through holes 161a or recesses.

The lower elastic member <NUM> may include a first lower elastic member 160a and a second lower elastic member 160b separated from each other, as exemplarily shown in <FIG>. Through such a two-split structure, the first lower elastic member 160a and the second lower elastic member 160b of the lower elastic member <NUM> may receive power having different polarities or different powers. That is, after the inner frame <NUM> and the outer frame <NUM> are combined with the bobbin <NUM> and the housing <NUM>, solder parts may be provided at positions of the inner frame <NUM> corresponding to both ends of the coil <NUM> disposed on the bobbin <NUM> and conductive connection, such as soldering, is performed at the solder parts and thus, the first lower elastic member 160a and the second lower elastic member 160b may receive power having different polarities or different powers. Further, the first lower elastic member 160a is electrically connected to one of both ends of the coil <NUM> and the second lower elastic member 160b is electrically connected to the other and thus, the first lower elastic member 160a and the second lower elastic member 160b may receive current and/or voltage supplied from the outside.

The upper elastic member <NUM>, the lower elastic member <NUM>, the bobbin <NUM>, and the housing <NUM> may be assembled by bonding using thermal fusion and/or an adhesive agent. Here, based on an assembly sequence, fixing using thermal fusion may be carried out and then, fixing may be finished through bonding using an adhesive agent.

In accordance with a modified embodiment, the upper elastic member <NUM> may have a two-split structure and the lower elastic member <NUM> may have an integrated structure.

At least one of the inner frame <NUM> and the outer frame <NUM> of the lower elastic member <NUM> may include at least one terminal part electrically connected to at least one of the coil <NUM> of the bobbin <NUM> and the printed circuit board <NUM>.

<FIG> is a schematic perspective view of the bobbin <NUM> in accordance with the embodiment, <FIG> is a schematic perspective bottom view of the bobbin <NUM> in accordance with the embodiment, <FIG> is a schematic exploded perspective view of the bobbin <NUM> in accordance with the embodiment, <FIG> is a partially enlarged perspective view of <FIG>, <FIG> is a partially enlarged bottom view of <FIG>, <FIG> is a partially enlarged perspective view of a reception recess <NUM> in accordance with the embodiment, and <FIG> is a schematic longitudinal-sectional view of the bobbin <NUM> in accordance with the embodiment.

As exemplarily shown in <FIG>, the bobbin <NUM> may be installed so as to reciprocate in the optical axis direction in the inner space of the housing <NUM>. The coil <NUM>, which will be described later, is installed on the outer surface of the bobbin <NUM>. The coil <NUM> may electromagnetically interact with the driving magnets <NUM> of the housing <NUM> and thus, the bobbin <NUM> may reciprocate in the first direction due to electromagnetic interaction between the coil <NUM> and the driving magnets <NUM>. Further, the bobbin <NUM> may be elastically (flexibly) supported by the upper elastic member <NUM> and the lower elastic member <NUM> and move in the optical axis direction, i.e., in the first direction, thus performing an auto-focusing function.

The bobbin <NUM> may include a lens barrel (not shown) in which at least one lens is installed, and the lens barrel is an element of the camera module, which will be described later, but is not essential to the lens moving apparatus. The lens barrel may be combined with the inside of the bobbin <NUM> through various methods. For example, a female screw thread may be formed on the inner surface of the bobbin <NUM>, a male screw thread may be formed on the outer surface of the lens barrel, and the lens barrel may be combined with the bobbin <NUM> through screw combination between the female screw thread and the male screw thread. However, the disclosure is not limited thereto, and the lens barrel may be fixed directly to the inside of the bobbin <NUM> through other methods except for the screw combination method without a screw thread formed on the inner surface of the bobbin <NUM>. Otherwise, one or more lenses may be formed integrally with the bobbin <NUM> without a lens barrel. One lens may be combined with the lens barrel or two or more lens combined with the lens barrel may form an optical system.

Further, a plurality of upper support protrusions <NUM> and a plurality of lower support protrusions <NUM> may protrude from the upper surface and the lower surface of the bobbin <NUM>.

The upper support protrusions <NUM> may have a cylindrical shape or a prism shape, and combine and fix the inner frame <NUM> of the upper elastic member <NUM> with and to the bobbin <NUM>, as exemplarily shown in <FIG>. In accordance with this embodiment, the second through holes 151a or recesses may be formed at positions of the inner frame <NUM> of the upper elastic member <NUM> corresponding to the upper support protrusions <NUM>. The upper support protrusions <NUM> and the second through holes 151a or recesses may be fixed through thermal fusion or using an adhesive member, such as epoxy. Further, the upper support protrusions <NUM> may be provided in plural. A separation distance between the upper support protrusions <NUM> may be properly adjusted within a range of avoiding interference with peripheral parts. That is, the upper support protrusions <NUM> may be disposed at regular intervals symmetrically with respect to the center of the bobbin <NUM>, or the upper support protrusions <NUM> may be disposed at irregular intervals symmetrically with respect to a specific virtual line passing through the center of the bobbin <NUM>.

The lower support protrusions <NUM> may have a cylindrical shape or a prism shape, in the same manner as the above-described upper support protrusions <NUM>, and combine and fix the inner frame <NUM> of the lower elastic member <NUM> with and to the bobbin <NUM>, as exemplarily shown in <FIG>. In accordance with this embodiment, the third through holes 161a or recesses may be formed at positions of the inner frame <NUM> of the lower elastic member <NUM> corresponding to the lower support protrusions <NUM>. The lower support protrusions <NUM> and the third through holes 161a or recesses may be fixed through thermal fusion or using an adhesive member, such as epoxy. Further, the lower support protrusions <NUM> may be provided in plural, as exemplarily shown in <FIG>. A separation distance between the lower support protrusions <NUM> may be properly adjusted within a range of avoiding interference with peripheral parts. That is, the lower support protrusions <NUM> may be disposed at regular intervals symmetrically with respect to the center of the bobbin <NUM>.

Upper escape recesses <NUM> and lower escape recesses <NUM> are formed at positions of the upper surface and the lower surface of the bobbin <NUM> corresponding to the connection parts <NUM> of the upper elastic member <NUM> and the connection parts <NUM> of the lower elastic member <NUM>.

The upper escape recesses <NUM> and the lower escape recesses <NUM> remove spatial interference between the connection parts <NUM> and <NUM> and the bobbin <NUM> when the bobbin <NUM> moves in the first direction with respect to the housing <NUM>, thus facilitating elastic deformation of the connection parts <NUM> and <NUM>. Further, although this embodiment describes the upper escape recesses <NUM> as being disposed at the corners of the housing <NUM>, the upper escape recesses <NUM> may be disposed on the side surfaces <NUM> of the housing <NUM> according to shapes and/or positions of the connection parts <NUM> of the upper elastic member <NUM>.

Further, a coil loading groove <NUM> in which the coil <NUM> is installed may be provided on the outer surface of the bobbin <NUM>, or only a loading part may be provided.

The coil <NUM> may be provided as a ring-shaped coil block inserted into or combined with the outer surface of the bobbin <NUM>, the coil loading groove <NUM>, or the loading part, but is not limited thereto. The coil <NUM> is wound directly on the outer surface of the bobbin <NUM>, the coil loading groove <NUM>, or the loading part.

In accordance with this embodiment, the coil <NUM> may be formed in an approximately octagonal shape, as exemplarily shown in <FIG>. Such a shape corresponds to the shape of the outer surface of the bobbin <NUM>, and the bobbin <NUM> may be formed also in an octagonal shape. Further, at least four surfaces of the coil <NUM> may be flat surfaces and corner parts of the coil <NUM> interconnecting the surfaces may be rounded surfaces or flat surfaces. The flat surfaces may be surfaces corresponding to the driving magnets <NUM>. Further, the surfaces of the driving magnets <NUM> corresponding to the coil <NUM> may have the same curvature as the curvature of the coil <NUM>. That is, if the surfaces of the coil <NUM> are flat surfaces, the corresponding surfaces of the driving magnets <NUM> may be flat surfaces and, if the surfaces of the coil <NUM> are curved surfaces, the corresponding surfaces of the driving magnets <NUM> may be curved surfaces and have the same curvature as the curvature of the surfaces of the coil <NUM>. Further, even if the surfaces of the coil <NUM> are curved surfaces, the corresponding surfaces of the driving magnets <NUM> may be flat surfaces, or vice versa.

The coil <NUM> serves to move the bobbin <NUM> in the optical axis direction to perform an auto-focusing function. When current is supplied, the coil <NUM> may generate electromagnetic force through electromagnetic interaction with the driving magnets <NUM> and then move the bobbin <NUM> through the generated electromagnetic force.

The coil <NUM> may correspond to the driving magnets <NUM>. As exemplarily shown in the drawings, if the driving magnet <NUM> is formed to have an integral body and the entire surface of the driving magnet <NUM> opposite the coil <NUM> has the same polarity, the surface of the coil <NUM> corresponding to the driving magnet <NUM> may have the same polarity. Although not shown in the drawings, if the driving magnet <NUM> is split into two sections along a surface vertical to the optical axis so that the surface of the driving magnet <NUM> opposite the coil <NUM> is divided into two or more sections, the coil <NUM> may be divided also into sections corresponding in number to the divided sections of the driving magnet <NUM>.

The bobbin <NUM> includes the sensing magnet <NUM> which, together with the position sensor <NUM> of the housing <NUM>, forms the sensing unit. The sensing magnet <NUM> is fixed to, disposed on, or combined with the bobbin <NUM>. Thereby, when the bobbin <NUM> moves in the first direction, the sensing magnet <NUM> may move in the first direction by the same displacement as the bobbin <NUM>. Further, the sensing magnet <NUM> may be formed in one body and disposed such that the upper portion of the bobbin <NUM> becomes the N pole and the lower portion of the bobbin <NUM> becomes the S pole. However, the disclosure is not limited thereto and vice versa. Further, the sensing magnet <NUM> may be split into two sections along a plane vertical to the optical axis.

The sensing magnet <NUM> may be formed in a size which does not influence the magnetic flux density of the driving magnets <NUM> corresponding to electromagnetic force driving the coil <NUM> so as not to influence the functions of the bobbin <NUM> and the coil <NUM>. Therefore, the sensing magnet <NUM> may be a magnet for Hall sensors or a subsidiary magnet having a smaller size than the driving magnets <NUM>. Such a size of the sensing magnet <NUM> may be <NUM>/<NUM> the size of the driving magnets <NUM>. However, since the sensing magnet <NUM> may be formed in a size which does not influence magnetic force of the driving magnets <NUM>, the sensing magnet <NUM> may be formed in a size less than or more than <NUM>/<NUM> the size of the driving magnets <NUM>.

As exemplarily shown in <FIG>, the bobbin <NUM> may have a reception recess <NUM> formed on the outer surface of the bobbin <NUM> so as to receive the sensing magnet <NUM>.

The reception recess <NUM> may be formed on the outer surface of the bobbin <NUM> to a designated depth in the inward direction of the bobbin <NUM>.

In more detail, the reception recess <NUM> may be formed on one side surface of the bobbin <NUM> such that at least a part of the reception recess <NUM> is located at the inside of the coil <NUM>. Further, at least a part of the reception recess <NUM> may be depressed more than the coil loading groove <NUM> to a designated depth in the inward direction of the bobbin <NUM>. By forming the reception recess <NUM> in the inward direction of the bobbin <NUM>, the sensing magnet <NUM> is received in the bobbin <NUM> and thus, a separate space for installation of the sensing magnet <NUM> is not required and space utilization of the bobbin <NUM> may be improved.

Particularly, the reception recess <NUM> may be disposed at a position corresponding to the position sensor <NUM> of the housing <NUM> (or a position opposite the position sensor <NUM>). Thereby, a distance between the sensing magnet <NUM> and the position sensor <NUM> includes the thickness of the coil <NUM> and/or a separation distance between the coil <NUM> and the position sensor <NUM> and may thus be minimized and thus, accuracy in sensing of magnetic force by the position sensor <NUM> may be improved.

The reception recess <NUM> may include an opening <NUM> formed on one of the upper surface and the lower surface of the bobbin <NUM> and communicating with the reception recess <NUM>. For example, as exemplarily shown in <FIG>, a part of the lower surface of the bobbin <NUM> may be opened and form the opening <NUM> and the opening <NUM> may form the inlet of the reception recess <NUM>. The sensing magnet <NUM> may be inserted into, disposed in, or fixed to the reception recess <NUM> through the opening <NUM>, and be separated from the reception recess <NUM> through the opening <NUM>.

In more detail, as exemplarily shown in <FIG>, the reception recess <NUM> may include an inner surface supporting one surface of the sensing magnet <NUM> and an adhesive groove 117b depressed more inwardly than the inner surface to a designated depth such that an adhesive agent is injected into the adhesive groove 117b.

The inner surface is one surface located in the inward direction toward the center of the bobbin <NUM> and, if the sensing magnet <NUM> has a rectangular parallelepiped shape, the wide surface of the sensing magnet <NUM> contacts or is loaded on the inner surface.

The adhesive groove 117b may be formed by depressing a part of the inner surface in the inward direction toward the center of the bobbin <NUM>. The adhesive groove 117b may be formed from the opening <NUM> to one inner surface of the bobbin <NUM> contacting one surface of the sensing magnet <NUM>.

As exemplarily shown in <FIG>, the adhesive groove 117b may include a first additional groove 117c formed to have a greater length than the length of the sensing magnet <NUM> in the thickness direction of the bobbin <NUM>. That is, the first additional groove 117c is an extension part of the adhesive groove <NUM> depressed more than one inner surface of the bobbin <NUM> contacting the other surface of the sensing magnet <NUM>. By forming the first additional groove 117c, when the adhesive agent is injected into the adhesive groove 117b through the opening <NUM>, the adhesive agent fills the inside of the adhesive groove 117b starting from the first additional groove 117c. Thereby, flow of the adhesive groove 117b to the coil <NUM> along a gap between the sensing magnet <NUM> and the reception recess <NUM> due to overflow of the adhesive agent from the adhesive groove 117b may be prevented and thus, an error generation rate of the lens moving apparatus <NUM> during a process of combining the sensing magnet <NUM> with the bobbin <NUM> may be reduced.

Further, the adhesive groove 117b may further include a second additional groove 117a formed to a designated depth in the inward direction from the opening <NUM> toward the center of the bobbin <NUM>. That is, the second additional groove 117a may be formed around the opening <NUM> more deeply than the inner surface in the inward direction toward the center of the bobbin <NUM>. The second additional groove 117a communicates with the adhesive groove 117b. That is, the second additional groove 117a is an extension part of the adhesive groove 117b. By forming the second additional groove 117a, the adhesive agent may be injected into the adhesive groove 117b through the second additional groove 117a. Thereby, adhesion of the adhesive agent to other elements of the bobbin <NUM>, such as the coil <NUM>, due to overflow of the adhesive agent around the opening <NUM> may be prevented and thus, an error generation rate of the lens moving apparatus <NUM> during a process of combining the sensing magnet <NUM> with the bobbin <NUM> may be reduced.

Further, in accordance with a modified embodiment, the second additional groove 117a may be provided directly on the bobbin <NUM> without the adhesive groove 117b. In this case, the sensing magnet <NUM> may be combined with and fixed to the bobbin <NUM> by injecting the adhesive agent into the second additional groove 117a.

The adhesive groove 117b may include at least one of the first additional groove 117c and the second additional groove 117a. That is, the adhesive groove 117b may include only the first additional groove 117c or include only the second additional groove 117a.

In accordance with another modified embodiment, a depth between the inner surface of the reception recess <NUM> supporting one surface (i.e., the wide surface) of the sensing magnet <NUM> and the outer surface of the bobbin <NUM> having the coil <NUM> (i.e., the surface of the coil loading groove <NUM>) may be less than the thickness of the sensing magnet <NUM>. Thereby, the sensing magnet <NUM> may be fixed to the inside of the reception recess <NUM> by inward pressing force of the coil <NUM> due to winding of the coil <NUM>. In this case, an adhesive agent does not need to be used.

In accordance with an additional embodiment, although not shown in the drawings, the bobbin <NUM> may further an additional reception recess <NUM> formed on the outer surface of the bobbin <NUM> at a position symmetrical to the reception recess <NUM> with respect to the center of the bobbin <NUM>, and a weight balance member received in the additional reception recess <NUM>.

That is, the additional reception recess <NUM> may be formed to a designated depth in the inward direction of the bobbin <NUM> on the outer surface of the bobbin <NUM> at a position symmetrical to the reception recess <NUM> on a straight line with respect to the center of the bobbin <NUM>. Further, the weight balance member is fixed to and combined with the inside of the additional reception recess <NUM> and has the same weight as the sensing magnet <NUM>.

By providing the additional reception recess <NUM> and the weight balance member, the weight balance member may compensate for weight unbalance of the bobbin <NUM> in the horizontal direction caused by the reception recess <NUM> and the sensing magnet <NUM>.

The additional reception recess <NUM> may include at least one of an adhesive groove 117b, a first additional groove 117c, and a second additional groove 117a.

<FIG> is a view illustrating a position sensor <NUM> in a mounted state in accordance with another embodiment. In accordance with this embodiment, the position sensor <NUM> may be provided on the inner surface of the cover member <NUM>.

With reference to <FIG>, if the position sensor <NUM> is disposed on the inner surface of the cover member <NUM>, the lower end of the position sensor <NUM> is connected to the printed circuit board <NUM> so as to communicate with the printed circuit board <NUM> and may thus receive power supplied from the printed circuit board <NUM>.

<FIG> is a view illustrating magnetic bodies in a mounted state in accordance with one embodiment. In this embodiment, the lens moving apparatus <NUM> may further include magnetic bodies <NUM>.

The magnetic bodies <NUM> may be mounted on the driving magnets <NUM>, be located between the driving magnets <NUM> and the coil <NUM>, and surface-contact the coil <NUM> and thus provide frictional force to movement of the bobbin <NUM> and the coil <NUM>.

The magnetic bodies <NUM> may be formed of a metal, such as an iron plate, so as to be attached to the driving magnets <NUM> by magnetic force, and support separation spaces between the coil <NUM> and the driving magnets <NUM> to reduce a pose difference (shaking of the bobbin <NUM>) caused by change of the position of the lens moving apparatus <NUM>. Therefore, two or more magnetic bodies <NUM> may be mounted on the inner surfaces of the driving magnets <NUM> so as to be opposite each other.

Therefore, the magnetic bodies <NUM> reduce a pose difference of the lens moving apparatus <NUM> and do not require the lens unit to continuously apply power to the coil <NUM> to maintain a specific position. Further, since the magnetic bodies <NUM> perform the function of an elastic unit, the lens moving apparatus <NUM> may be operated without a separate elastic unit, such as the upper and lower elastic members <NUM> and <NUM>, miniaturization of the lens moving apparatus <NUM> in the first direction and effective utilization of the inner space of the lens moving apparatus <NUM> may be achieved.

Therefore, the lens moving apparatus <NUM> in accordance with this embodiment includes the magnetic bodies <NUM> and thus exhibits prevention of eccentricity of the bobbin <NUM> and the function of the upper and lower elastic members <NUM> and <NUM>, thus having improved reliability.

As described above, the lens moving apparatus <NUM> in accordance with this embodiment may readjust the position of a lens in the optical axis direction through feedback of the displacement of the lens in the optical axis direction and thus shorten a focus alignment time of the lens.

Further, the lens moving apparatus <NUM> in accordance with this embodiment may minimize an interval between the sensing magnet provided on a movable body, i.e., the bobbin, and the position sensor provided on a fixed body, i.e., the housing, more accurately sense the displacement of the lens in the optical axis direction, and thus more accurately and rapidly locate the lens at the focal distance of the lens.

Further, the lens moving apparatus <NUM> in accordance with this embodiment locates the sensing magnet in the bobbin and locates the position sensor in the housing and does not require a separate space for mounting of the sensing unit, thus improving space utilization of the camera module (particularly, the bobbin).

Further, the lens moving apparatus <NUM> in accordance with this embodiment may include the lens combined with the lens moving apparatus <NUM>, provide the camera module disposed thereunder and including the image sensor and the printed circuit board on which the image sensor is disposed, and combine the base of the lens moving apparatus with the printed circuit board.

Further, the camera module may further include the camera module controller and the camera module controller may compare a first displacement value, calculated based on the current change value sensed by the sensing unit, with the focal distance of the lens according to the distance between a subject and the lens. Thereafter, the camera module controller, if the first displacement value or the current position of the lens does not correspond to the focal distance of the lens, readjusts an amount of current applied to the coil <NUM> of the bobbin <NUM> and may thus move the bobbin <NUM> by a second displacement in the first direction. Further, in the sensing unit, the position sensor <NUM> fixed to a fixed body, i.e., the housing <NUM>, may sense change of magnetic force emitted from the sensing magnet <NUM> according to movement of the sensing magnet <NUM> fixed to a movable body, i.e., the bobbin <NUM>, a separate driver IC or the camera module controller may calculate or judge the current position or the first displacement of the bobbin <NUM> based on change of current output based on the sensed change of magnetic force, the current position or the first displacement of the bobbin <NUM>, calculated or judged by the sensing unit, is transmitted to the controller of the printed circuit board <NUM>, and the controller may redetermine the position of the bobbin <NUM> for auto-focusing and thus adjust an amount of current applied to the coil <NUM>.

<FIG> is a perspective view of a further lens moving apparatus, <FIG> is a perspective view of the lens moving apparatus of <FIG>, from which a yoke unit <NUM> is removed, <FIG> is an exploded perspective view of the lens moving apparatus, and <FIG> is a view illustrating a cover member <NUM>, as seen from the bottom. With reference to <FIG>, the lens moving apparatus in accordance with this further embodiment may include a movable element <NUM> and a cover member <NUM>.

The movable element <NUM> includes a bobbin <NUM> and a coil <NUM>. The bobbin <NUM> is combined with the lens unit <NUM> and thus fixes the lens unit <NUM>. The lens unit <NUM> and the bobbin <NUM> may be combined through screw combination using screw threads <NUM> respectively formed on the inner surface of the bobbin <NUM> and the outer surface of the lens unit <NUM>, as exemplarily shown in <FIG>, or be combined using an adhesive agent without formation of screw threads. Of course, the bobbin <NUM> and the lens unit <NUM> may be more firmly combined using the adhesive agent after screw combination has been completed.

Further, guide parts <NUM> guiding winding or mounting of the coil <NUM>, which will be described later, may be formed on the outer surface of the bobbin <NUM>. The guide parts <NUM> may be formed integrally with the outer surface of the bobbin <NUM> and be formed continuously along the outer surface of the bobbin <NUM> or be formed so as to be separated by designated intervals.

Further, fastening protrusions <NUM> to which an upper elastic member and/or a lower elastic member to support the bobbin <NUM> above the base <NUM> are fastened may be formed on the upper surface and/or the lower surface of the bobbin <NUM>.

Further, a recess <NUM> to locate a yoke unit <NUM>, which will be described later, between the bobbin <NUM> and the coil <NUM> wound on the bobbin <NUM> is formed on the outer surface of the bobbin <NUM>.

The lens unit <NUM> may be a lens barrel but is not limited thereto. That is, the lens unit <NUM> may include any holder structure which may support lenses. In this embodiment, a lens barrel will be exemplarily described as the lens unit <NUM>. The lens unit <NUM> is installed on a printed circuit board (not shown), which will be described later, and is disposed at a position corresponding to an image sensor. The lens unit <NUM> includes one or more lenses (not shown).

The coil <NUM> may be guided by the guide parts <NUM> and wound on the outer surface of the bobbin <NUM>, or four respective coils may be arranged at intervals of <NUM>° on the outer surface of the bobbin <NUM>. The coil <NUM> may receive power supplied from the printed circuit board, which will be described later, and form an electromagnetic field.

The cover member <NUM> may include the driving magnets <NUM>, the yoke unit <NUM>, and the base <NUM>.

The driving magnets <NUM> may be mounted on the yoke unit <NUM> so as to be disposed at positions corresponding to the outer surface of the coil <NUM>. As exemplarily shown in <FIG>, the driving magnets <NUM> may be mounted at four corners of the inside of the yoke unit <NUM> at the same interval and thus facilitate effective utilization of the inner volume of the yoke unit <NUM>.

Although the driving magnets <NUM> may have a triangular prism shape, the inner surface of which is curved, as exemplarily shown in <FIG>, the driving magnets <NUM> may have a prism shape, such as a rectangular prism or a trapezoidal prism, according to inner structural change.

The yoke unit <NUM> forms the external appearance of the lens moving apparatus, an opening having a greater diameter than the diameter of the bobbin <NUM> is formed on the upper surface of the yoke unit <NUM>, and the lower surface of the yoke unit <NUM> is opened. Here, magnet fixing parts <NUM> bent in the downward direction to fix the driving magnets <NUM> may be formed at the opening, and a terminal groove <NUM> corresponding to a terminal part <NUM> of a position sensor <NUM>, which will be described later, may be formed on the end of a side surface of the yoke unit <NUM> so as to expose the terminal part <NUM> to the outside.

Such a yoke unit <NUM> receives an elastic unit, which will be described later, the movable element <NUM> and the cover member <NUM> and is mounted on the base <NUM>, thus forming the external appearance of a camera module. In more detail, the yoke unit <NUM> is mounted on the base <NUM> such that the inner surface of the yoke unit <NUM> is adhered to the side surface of the base <NUM>, which will be described later, and has both a function of protecting inner components of the camera module and a function of preventing external contaminants from being introduced into the camera module.

Further, the yoke unit <NUM> needs to perform a function of protecting the components of the camera module from interference with external waves generated from a cellular phone. Therefore, the yoke unit <NUM> may be implemented as a cover can formed of a metal.

Further, although not shown in the drawings, the yoke unit <NUM> includes at least one extended fastening piece on each surface of the lower end thereof and the base <NUM> includes fastening recesses into which the fastening pieces are inserted and thus, firm sealing and fastening effects of the camera module may be achieved.

The base <NUM> may be disposed at the lower portion of the lens moving apparatus so as to support the yoke unit <NUM> and the movable element <NUM>.

In more detail, the base <NUM> supports the cover member <NUM> and the movable element <NUM>, a recess <NUM> having a circular shape and depressed downwards is formed at the center of the base <NUM> so that bobbin <NUM> may be located in the recess <NUM>, a loading groove 211a to load the position sensor <NUM>, which will be described alter, is formed at the side of the recess <NUM>, and a through hole 211b corresponding to the lens unit <NUM> may be formed at the center of the base <NUM>.

The base <NUM> may perform the function of a sensor holder protecting a image sensor (not shown), which will be described later, and the through hole 211b may be provided to locate a filter (not shown). In this case, the filter may be an infrared filter. Further, the filter may be formed of a film or glass. The filter may be formed by applying an IR cut-off coating material to a flat panel type optical filter, such as a cover glass for protecting a photographing surface. Further, in addition to the base <NUM>, a separate sensor holder may be additionally located under the base <NUM>.

One or more fixing protrusions <NUM> surface-contacting or combined with the inner surface of the yoke unit <NUM> may be formed at corners of the upper surface of the base <NUM>. The fixing protrusions <NUM> may perform guiding of the yoke unit <NUM> and firm fixing of the yoke unit <NUM> after guiding.

Further, fastening protrusions <NUM> to which a lower elastic member, which will be described later, is fastened may be formed on the upper surface <NUM>.

Further, although not shown in the drawings, the fastening recesses into which the fastening pieces of the yoke unit <NUM> are inserted may be formed on the base <NUM>. Such fastening recesses may be formed in a shape corresponding to the length of the fastening pieces. The fastening recesses may be formed locally on the outer surface of the base <NUM>, or be formed throughout the outer surface of the base <NUM> so that a designated part of the lower end of the cover can including the fastening pieces may be inserted thereinto.

The lens moving apparatus in accordance with this embodiment includes the sensing magnet <NUM> and the position sensor <NUM> and may thus detect position information of the movable element <NUM> and perform feedback of the position information, thereby more rapidly and accurately achieving lens movement.

The sensing magnet <NUM> is provided at one side of the bobbin <NUM>. Here, one side means a part of the side surface of the bobbin <NUM>, and the sensing magnet <NUM> may be inserted into the lower portion of the side surface of the bobbin <NUM> or be mounted in a recess formed at the upper region, the lower region, or the center of the bobbin <NUM>.

The sensing magnet <NUM> may be formed in a size which does not influence the magnetic flux density of the driving magnets <NUM> corresponding to electromagnetic force driving the coil <NUM> so as not to influence the functions of the movable element <NUM>. Therefore, the sensing magnet <NUM> may be a magnet for Hall sensors or a subsidiary magnet having a smaller size than the driving magnets <NUM>. Such a size of the sensing magnet <NUM> may be <NUM>/<NUM> the size of the driving magnets <NUM>. However, since the sensing magnet <NUM> may be formed in a size which does not influence magnetic force of the driving magnets <NUM>, the sensing magnet <NUM> may be formed in a size less than or more than <NUM>/<NUM> the size of the driving magnets <NUM>.

In this embodiment, since the sensing magnet <NUM> is provided and thus, instead of the driving magnets <NUM>, the coil <NUM> may be disposed on the movable element <NUM>, the movable element <NUM> may be lightweight. Such a movable element <NUM> may reduce eccentricity of the lens unit <NUM> even if a user locates the camera module at any position, and the lens moving apparatus may achieve more free inner structure utilization than a conventional lens moving apparatus through rapid and precise control of the lightweight movable element <NUM> and the arrangement structure of the position sensor <NUM>.

The position sensor <NUM> is provided to sense movement of the sensing magnet <NUM> and to precisely control the movable element <NUM>, and at least one position sensor <NUM> may be provided.

The position sensor <NUM> may be located closer to the coil than the sensing magnets <NUM>. When taking into consideration that the intensity of a magnetic field formed by a magnet is several hundreds times the intensity of an electromagnetic field formed by a coil, influence of the coil <NUM> is not considered in sensing of movement of the sensing magnet <NUM>.

The position sensor <NUM> is disposed so as to correspond to the sensing magnet <NUM>. The position sensor <NUM> is disposed outside the sensing magnet <NUM>, as exemplarily shown in <FIG> or <FIG>.

In the case of the former, the position sensor <NUM> may be loaded in the loading groove 211a of the recess <NUM> formed on the base <NUM>, as exemplarily shown in <FIG>. In the case of the latter, the position sensor <NUM> may be provided on the inner surface of the yoke unit <NUM>, as exemplarily shown in <FIG> and <FIG>.

The position sensor <NUM> may include a Hall sensor <NUM> disposed so as to correspond to the sensing magnet <NUM> and the terminal part <NUM> electrically connected to the Hall sensor <NUM> and receiving power supplied from the outside. Further, although not shown in the drawings, the lens moving apparatus in accordance with this embodiment may further include an elastic unit. The elastic unit includes an upper elastic member and a lower elastic member.

Although each of the upper elastic member and the lower elastic member may include separate elastic members disposed on respective sides of the housing, each of the upper elastic member and the lower elastic member may be formed of a single plate which is bent and cut, for efficiency of manufacture.

The upper elastic member is fastened to the upper surface of the yoke unit <NUM> and the upper surface of the bobbin <NUM> and supports the bobbin <NUM>. In order to provide restoring force to the bobbin <NUM> when the bobbin <NUM> moves upwards, the upper elastic member is provided at the upper end of the yoke unit <NUM>. In more detail, the upper elastic member is disposed at the upper end of the yoke unit <NUM>, protrudes from the opening formed at the upper end of the yoke unit <NUM> in the inward direction to have a designated area, and the protruding part of the upper elastic member supports the upper end of the bobbin <NUM>.

Since the yoke unit <NUM> may be formed of a metal, an insulating plate <NUM> formed of an insulating material may be provided between the yoke unit <NUM> and the upper elastic member. Further, a lid <NUM> formed in a shape corresponding to the upper surface of the yoke unit <NUM> may be mounted on the upper end of the upper elastic member.

Corresponding holes are formed on the lid <NUM>, the upper elastic member, the insulating plate <NUM>, and the upper surface of the yoke unit <NUM> and thus, the lid <NUM>, the upper elastic member, the insulating plate <NUM>, and the yoke unit <NUM> may be fastened using an adhesive agent applied to the holes.

The edge of the lower elastic member is supported by the upper surface of the base <NUM>, and the inner circumferential part of the lower elastic member supports the lower end of the bobbin <NUM>. In more detail, the lower elastic member may include two corresponding plate springs, and the plate springs may be electrically connected to one end and the other end of the coil <NUM> wound on the bobbin <NUM> and thus transmit power to the coil <NUM>. That is, the lower elastic member may include separate plate springs for input and output of power that are symmetrical with respect to the optical axis. Of course, the upper elastic member may be formed in the same manner as the lower elastic member.

The lens moving apparatus in accordance with this embodiment may further include magnetic bodies <NUM>. The magnetic bodies <NUM> may be mounted on the driving magnets <NUM>, be located between the driving magnets <NUM> and the coil <NUM>, and surface-contact the coil <NUM> and thus provide frictional force to movement of the movable element <NUM>.

The magnetic bodies <NUM> may be formed of a metal, such as an iron plate, so as to be attached to the driving magnets <NUM> by magnetic force, and support separation spaces between the coil <NUM> and the driving magnets <NUM> to reduce a pose difference (shaking of the movable element <NUM>) caused by change of the position of the lens moving apparatus <NUM>. Therefore, two or more magnetic bodies <NUM> may be mounted on the inner surfaces of the driving magnets <NUM> so as to be opposite each other.

Therefore, the magnetic bodies <NUM> reduce a pose difference of the lens moving apparatus and do not require the lens unit <NUM> to continuously apply power to the coil <NUM> to maintain a specific position. Further, since the magnetic bodies <NUM> perform the function of an elastic unit, the lens moving apparatus may be operated without a separate elastic unit and thus, miniaturization of the lens moving apparatus in the optical axis direction and effective utilization of the inner space of the lens moving apparatus may be achieved.

The lens moving apparatus in accordance with this embodiment may be mounted on a camera module, and such a camera module may be provided in various kinds of multimedia apparatuses, such as a cellular phone, a notebook personal computer, a camera phone, a PDA, a smartphone, and a toy, and further in image input apparatuses, such as a CCTV camera and an information terminal of a video tape recorder.

For example, if the lens moving apparatus in accordance with this embodiment may be provided in a camera module, the camera module may further include a printed circuit board (not shown) and an image sensor (not shown).

The image sensor (not shown) may be mounted at the center of the upper surface of the printed circuit board, and various elements (not shown) to drive the camera module may be mounted on the printed circuit board. Further, in order to apply power to drive the lens moving apparatus in accordance with this embodiment, the printed circuit board may be electrically connected to the terminal part <NUM>, the lower elastic member or the upper elastic member, or be electrically connected directly to the coil <NUM>.

The image sensor (not shown) may be mounted at the center of the upper surface of the printed circuit board so as to be located in the optical axis direction together with one or more lenses (not shown) received in the lens unit <NUM>. Such an image sensor converts an optical signal of a target object, incident through the lenses, into an electrical signal.

The above-described adhesive agent may be implemented as thermosetting epoxy or UV epoxy and be cured by heat or exposure to UV light. If thermosetting epoxy is used, the adhesive agent is moved to an oven and is cured by applying heat directly thereto and, if UV epoxy is used, the adhesive agent is cured by applying UV light thereto.

Further, the adhesive agent may be epoxy in which heat curing and UV light curing may be mixed. That is, the adhesive agent may be epoxy in which both heat curing and UV light curing are possible and one of these methods is selected. The adhesive agent is not limited to epoxy and may employ any adhesive material.

As is apparent from the above description, a lens moving apparatus in accordance with one embodiment may readjust the position of a lens in the optical axis direction through feedback of the displacement of the lens in the optical axis direction and thus shorten a focus alignment time of the lens. Further, the lens moving apparatus in accordance with the embodiment may minimize an interval between a sensing magnet provided on a movable body, i.e., a bobbin, and a position sensor provided on a fixed body, i.e., a housing, more accurately sense the displacement of the lens in the optical axis direction, and thus more accurately and rapidly locate the lens at the focal distance of the lens.

Further, the lens moving apparatus in accordance with the embodiment locates the sensing magnet in the bobbin or on the inner surface of a cover member and locates the position sensor in the housing, and does not require a separate space for mounting of a sensing unit, thus improving space utilization of a camera module (particularly, the bobbin).

Further, the lens moving apparatus in accordance with the embodiment includes the sensing magnet and may thus minimize lowering of performance of the bobbin due to movement, and reduces a limit in disposition of the position sensor and may thus achieve effective focus correction.

Claim 1:
A lens moving apparatus (<NUM>), comprising:
a base (<NUM>);
a housing (<NUM>) disposed on the base (<NUM>);
a bobbin (<NUM>) disposed inside the housing (<NUM>), and configured to move in a first direction along or parallel with an optical axis within the housing (<NUM>);
driving magnets (<NUM>) disposed on the housing (<NUM>);
a coil (<NUM>) disposed on an outer surface of the bobbin (<NUM>);
an elastic member (<NUM>, <NUM>) supporting the bobbin (<NUM>);
a sensing magnet (<NUM>) coupled to the bobbin (<NUM>);
a printed circuit board (<NUM>) disposed on the housing (<NUM>); and
a position sensor (<NUM>) disposed on a part of the printed circuit board (<NUM>) on a surface of the housing (<NUM>) not disposed with the driving magnets (<NUM>) and at a position corresponding to the position of the sensing magnet (<NUM>),
wherein the driving magnets (<NUM>) are disposed on opposite sides of the housing (<NUM>),
wherein the position sensor (<NUM>) is configured to sense a displacement of the sensing magnet (<NUM>) in the first direction,
wherein the bobbin (<NUM>) comprises a reception recess (<NUM>) formed on the outer surface of the bobbin (<NUM>) to receive the sensing magnet (<NUM>),
wherein the sensing magnet (<NUM>) is disposed in the reception recess (<NUM>),
the coil (<NUM>) is wound circumferentially on the bobbin (<NUM>),
characterised in that
a part of the coil (<NUM>) is disposed between the sensing magnet (<NUM>) and the position sensor (<NUM>).