KR102275740B1 - Camera module - Google Patents

Abstract

The camera module of the embodiment includes a bobbin to which at least one lens is mounted, a position detecting unit that detects the position of the bobbin in the optical axis direction and outputs it as position information, and a first facing each other to move the bobbin in the optical axis direction of the lens. The autofocus function is performed by controlling the interaction between the first coil and the driving magnet according to the coil and the driving magnet and given subject information and location information, and moving the bobbin by the first movement amount in the first direction parallel to the optical axis. It includes a focus control unit.

Description

camera module

The embodiment relates to a camera module.

In recent years, the development of IT products such as a mobile phone, a smart phone, a tablet PC, and a notebook computer with a built-in digital camera is being actively conducted. Accordingly, a camera module having a digital camera is required to provide various functions such as auto focusing, shutter, shake improvement or zoom function, and the trend is higher in pixels and smaller in size.

Meanwhile, in the case of the conventional camera module, since the position of the subject cannot be known, a difference in resolution of the actuator may occur depending on the degree of hysteresis or repeatability. As described above, the existing camera module may also have a problem in that it takes a long time for the auto-focus function.

The embodiment provides a camera module capable of performing an autofocus function quickly and accurately.

A camera module according to an embodiment includes a bobbin to which at least one lens is mounted; a position detecting unit detecting the position of the bobbin in the optical axis direction and outputting it as position information; a first coil and a driving magnet facing each other to move the bobbin in the optical axis direction of the lens; and controlling the interaction between the first coil and the driving magnet according to the given subject information and the location information to move the bobbin by a first movement amount in a first direction parallel to the optical axis to perform an autofocus function It may include a focus control unit.

The subject information may include at least one of a distance between a subject and the at least one lens, a position of the subject, and a phase of the subject.

The focus controller may include: an information receiver configured to receive the subject information; a bobbin position search unit that finds a position of the bobbin in focus corresponding to the received subject information; and a movement amount adjusting unit configured to move the bobbin to the found position by the first movement amount based on the location information.

The bobbin position search unit may include: a look-up table for mapping and storing a position of the bobbin in focus corresponding to the subject information; and a data extractor for extracting a position of the bobbin in focus corresponding to the received subject information from the lookup table.

The lookup table may be stored by coding the position of the bobbin.

The lookup table may be generated using the position detecting unit before moving the bobbin by the first moving amount.

After moving the bobbin by the first movement amount, the focus control unit moves the bobbin within a range of a second movement amount smaller than the first movement amount, and the final focus of the bobbin showing the largest value among the frequency modulation transfer function values. location can be found.

The focus control unit may move the bobbin for a predetermined period or a predetermined number of times to find the largest value among the frequency modulation transfer function values.

The camera module further includes a second coil disposed to face the driving magnet, and the second and third directions are perpendicular to the first direction by interaction between the second coil and the driving magnet. The bobbin may be movable.

The camera module may further include an image sensor that outputs the subject information to the focus controller.

The camera module according to the embodiment may perform an autofocus function quickly and accurately.

1 is a schematic perspective view of a lens driving device according to an embodiment.
FIG. 2 is a schematic exploded perspective view showing an embodiment of the lens driving device illustrated in FIG. 1 .
FIG. 3 is a schematic perspective view of a lens driving device in which a cover can is removed in FIG. 1 according to an embodiment.
4 is a schematic plan perspective view of a housing member according to an embodiment.
5 is a schematic bottom perspective view of a housing member according to an embodiment.
6 is a schematic exploded perspective view of a driving magnet, a housing member, a first circuit board, and a position sensing unit according to an exemplary embodiment.
7 is a plan perspective view of an upper elastic member.
8 is a plan perspective view of the lower elastic member.
9 is a plan perspective view of the bobbin shown in FIG. 2 according to an embodiment.
10 is a bottom perspective view of the bobbin shown in FIG. 2 according to an embodiment.
11 is an exploded perspective view illustrating a bobbin, a first coil, a position sensing unit, and a sensing magnet according to an exemplary embodiment.
12 is a schematic bottom perspective view of a bobbin, a first coil, first and second driving magnets, a position sensing unit, and a sensing magnet according to an exemplary embodiment.
13 is a flowchart illustrating an auto-focus function performed by a focus control unit of a camera module according to an exemplary embodiment.
14 is a block diagram of a focus control unit according to an exemplary embodiment.
15 (a) and (b) are graphs for explaining an auto-focus function according to a comparative example.
16 (a) and (b) are graphs for explaining an auto-focus function according to an embodiment.
17 (a) and (b) are graphs for explaining fine adjustment in the auto focus function according to the embodiment.

Hereinafter, preferred embodiments of the embodiments will be described so that those of ordinary skill in the art can easily implement them with reference to the accompanying drawings. In the accompanying drawings, it may be noted that the reference numbers indicated for the components are used as much as possible when referring to the same components in other drawings. In addition, in the description of the embodiment, if it is determined that a detailed description of a related known function or a known configuration may unnecessarily obscure the gist of the embodiment, the detailed description thereof may be omitted. In addition, certain features presented in the drawings are enlarged, reduced, or simplified for ease of description, and the drawings and components thereof are not necessarily drawn to scale. However, those skilled in the art will readily appreciate these details.

The camera module according to the embodiment may include the lens driving device 100 and the focus controller 300 . Here, the camera module may be applied to a mobile device such as a mobile phone.

Hereinafter, the lens driving apparatus 100 of the camera module according to the embodiment will be described with reference to FIGS. 1 to 12 as follows. Although the embodiment illustrated in FIGS. 1 to 12 is described using a Cartesian coordinate system (x, y, z), the embodiment is not limited thereto. That is, it goes without saying that the embodiment can be described using another coordinate system. In each drawing, the x-axis and the y-axis mean a plane perpendicular to the optical axis. For convenience, the z-axis direction, which is the optical axis direction, may be referred to as the first direction, the x-axis direction as the second direction, and the y-axis direction as the third direction. .

1 is a schematic perspective view of a lens driving apparatus 100 according to an embodiment, FIG. 2 is a schematic exploded perspective view according to an embodiment of the lens driving apparatus 100 illustrated in FIG. 1 , and FIG. 3 is 1 shows a schematic perspective view of the lens driving device 100 in which the cover can 102 is removed according to an embodiment.

The lens driving apparatus 100 according to the embodiment is controlled by a focus controller 300 to be described later, so that the distance between the lens (not shown) and the image sensor (not shown) is adjusted so that the image sensor is positioned at the focal length of the lens can make it happen That is, the focus controller 300 may perform an 'auto-focus function' of automatically focusing the lens in the lens driving apparatus 100 .

1 to 3 , the lens driving device 100 according to the embodiment includes a cover can 102 , a bobbin 110 , a first coil 120 , a driving magnet 130 , and a housing member. 140 , an upper elastic member 150 , a lower elastic member 160 , a first circuit board 170 , a position sensing unit 180 , a sensing magnet 182 , and a base 190 . .

The cover can 102 may be in the form of a box as a whole, and may be configured to be mounted, seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed on the upper portion of the base 190 . The cover can 102 is mounted, seated, contacted, fixed, temporarily fixed, supported, combined, or disposed on the base 190 in the receiving space formed by the bobbin 110, the first coil 120, and the driving magnet 130 ), the housing member 140 , the upper elastic member 150 , the lower elastic member 160 , the first circuit board 170 , the position detecting unit 180 , and the sensing magnet 182 may be accommodated therein.

The cover can 102 may include an opening 101 on its upper surface through which a lens (not shown) coupled to the bobbin 110 can be exposed to external light. In addition, a window made of a light-transmitting material may be provided in the opening 101 to prevent foreign substances such as dust or moisture from penetrating into the camera module.

The cover can 102 may include a first groove portion 104 formed in a lower portion, and the base 190 may include a second groove portion 192 formed in an upper portion thereof. At this time, as will be described later, when the cover can 102 is mounted, seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed on the base 190, the portion in contact with the first groove 104 (that is, A second groove 192 may be formed in a position corresponding to the first groove 104 . A concave portion having a predetermined area may be formed by contacting, disposing, or combining the first groove portion 104 and the second groove portion 192 . An adhesive member having a viscosity, for example, epoxy may be injected into the groove and applied thereto. That is, the adhesive member applied to the concave portion fills a gap between the facing surfaces of the cover can 102 and the base 190 through the concave portion, so that the cover can 102 is mounted on the base 190 . , can be seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed to seal between the cover can 102 and the base 190, and the cover can 102 is mounted on the base 190, The sides may be closed or coupled while seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed.

In addition, the cover can 102 may further include a third groove portion 106 . Here, the third groove portion 106 is formed on a surface corresponding to the terminal surface of the first circuit board 170 , and can prevent the plurality of terminals 171 and the cover can 102 formed on the terminal surface from interfering with each other. have. The third groove portion 106 may be concavely formed on the entire surface facing the terminal surface of the first circuit board 170 , and an adhesive member is applied to the inside of the third groove portion 106 to cover the can 102 and the cover can 102 . The base 190 and the first circuit board 170 may be sealed or coupled.

The first groove portion 104 and the third groove portion 106 may be formed in the cover can 102 , and the second groove portion 192 may be formed in the base 190 , but the embodiment is not limited thereto. That is, according to another embodiment, the first to third grooves 104 , 192 , and 106 may be formed only on the base 190 or only on the cover can 102 .

In addition, the material of the above-described cover can 102 may include metal, but the embodiment is not limited to the material of the cover can 102 . In addition, the cover can 102 may be formed of a magnetic material.

The base 190 may be provided in a rectangular shape as a whole, and may include a stepped portion protruding a predetermined thickness outward to surround the lower edge of the base 190 . The stepped portion may be in the form of a continuous band or some intermittent band in the middle. The predetermined thickness of the stepped portion is the same as the side thickness of the cover can 102 , and when the cover can 102 is mounted, seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed on the base 190 , the cover can The side of 102 may be mounted, seated, contacted, coupled, fixed, supported, or disposed on the top or side of the stepped portion. For this reason, the cover can 102 coupled to the upper side of the stepped portion may be guided by the stepped portion, and further, the end of the cover can 102 may be coupled to face the stepped portion. Here, the end of the cover can 102 may include a bottom surface or a side surface. In this case, the stepped portion and the end of the cover can 102 may be adhesively fixed or bonded or sealed by an adhesive or the like.

In the stepped portion, a second groove portion 192 may be formed at a position corresponding to the first groove portion 104 of the cover can 102 . As described above, the second groove portion 192 may be combined with the first groove portion 104 of the cover can 102 to form a groove portion, and may form a space in which the adhesive member is filled.

Like the cover can 102 , the base 190 may include an opening near the center. The opening may be formed at a position corresponding to the position of the image sensor disposed in the camera module.

In addition, the base 190 may include four guide members 194 protruding at right angles to a predetermined height upward from the four corners. The guide member 194 may have a polygonal prism shape. The guide member 194 may be mounted, inserted, seated, contacted, coupled, fixed, supported, or disposed in the lower guide groove 148 of the housing member 140 to be described later. In this way, due to the guide member 194 and the lower guide groove 148 shown in FIG. 4 to be described later, the housing member 140 is mounted, seated, contacted, coupled, fixed, supported, or seated on the upper portion of the base 190 , or When disposed, the position such as coupling of the housing member 140 on the base 190 may be guided, the coupling area may be increased, and the housing member 140 may vibrate during the operation of the lens driving device 100 . It can be prevented from being separated from the reference position to be mounted, etc. due to reasons such as or due to an operator's mistake during the coupling process.

4 is a schematic plan perspective view of a housing member 140 according to an embodiment, FIG. 5 is a schematic bottom perspective view of the housing member 140 according to an embodiment, and FIG. 6 is a driving unit according to an embodiment. A schematic exploded perspective view of the magnet 130 , the housing member 140 , the first circuit board 170 , and the position sensing unit 180 is shown, and FIG. 7 is a plan perspective view of the upper elastic member 150 , FIG. 8 shows a plan perspective view of the lower elastic member 160 .

4 to 6 , the housing member 140 may have an overall hollow column shape (eg, a hollow quadrangular column shape as illustrated). The housing member 140 has a shape to support at least two or more driving magnets 130 and the first circuit board 170 , and the bobbin 110 therein has a first direction z with respect to the housing member 140 . The bobbin 110 may be accommodated to be movable in the axial direction.

The housing member 140 may include four flat sides 141 . The side surface 141 of the housing member 140 may be formed to have an area corresponding to or larger than that of the driving magnet 130 .

As shown in FIG. 6 , a driving magnet 130 is mounted, inserted, seated, contacted, combined, fixed, supported, or A through hole (or groove) 141a for a magnet that may be disposed may be formed. The through-hole 141a for the magnet may have a size and/or a shape corresponding to the driving magnet 130 , and may also have a shape capable of guiding the driving magnet 130 . One of the driving magnets 130 (hereinafter, 'first driving magnet 131 ') and the other one (hereinafter, 'second driving use') in each of the first and second through-holes 141a and 141a' for magnets The magnets 132') may be mounted, inserted, seated, contacted, coupled, fixed, supported, or disposed, respectively. In the case of the embodiment, only two driving magnets 130 are shown, but the embodiment is not limited thereto. That is, of course, four driving magnets 130 may be disposed.

The type of the driving magnet 130 described above can be broadly divided into ferrite, alnico, and rare earth magnets, and can be divided into an inner magnetic type (Ptype) and an outer magnetic type (F-type) according to the shape of the magnetic circuit. can be classified. The embodiment is not limited to the type of the driving magnet 130 .

And, among the four side surfaces 141 of the housing member 140, a position sensing unit 180 to be described later is mounted, inserted, seated, contacted, combined, on one side perpendicular to the first both sides or on a side other than the first both sides, A through hole 141b or a groove (not shown) for a sensor to be fixed, supported, or disposed may be formed. The sensor through-hole 141b may have a size and shape corresponding to the position sensing unit 180 to be described later, and may be formed to be spaced apart from the first and second magnet through-holes 141a and 141a' by a predetermined distance. The through-hole 141b for positioning may be formed in a side surface on which the first circuit board 170 is mounted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed among the side surfaces 141 of the housing member 140 . have.

In addition, on one side of the housing member 140, at least one mounting protrusion 149 for allowing the first circuit board 170 to be mounted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed. can be provided.

The mounting protrusion 149 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed in the mounting through hole 173 formed in the first circuit board 170 . At this time, the mounting through-hole 173 and the mounting protrusion 149 may be contacted or coupled in a shape fitting method or an interference fitting method, but these 173 and 149 are the first circuit board 170 in the housing. Mounting, seating, contact, coupling, fixing, temporarily fixing, supporting, or disposed on the member 140 may be a simple guide.

Here, the other side opposite to one side among the four side surfaces 141 of the housing member 140 may be configured as a flat plane, but is not limited thereto.

Although not shown, through-holes for the third and fourth magnets may be additionally disposed on the second side surfaces of the housing member 140 that are perpendicular to the first side surfaces.

At this time, the first through-hole 141a for the magnet and the second through-hole 141a' for the magnet have the same size and the same shape, and (almost) the same over the entire lateral length of the first both sides of the housing member 140 It may have a lateral length. On the other hand, the third through-hole for the magnet and the fourth through-hole for the magnet have the same size and the same shape as each other, and have a lateral length than the first through-hole (141a) for the magnet and the through-hole (141a') for the second magnet. can be made small. This is to secure a space for the sensor through-hole 141b since the sensor through-hole 141b must be formed on the second both side surfaces where the third or fourth through-hole for the magnet is formed.

The first driving magnet 131 and the second driving magnet 132 have the same size and shape as each other, and having substantially the same lateral length over the entire lateral length of the first both sides of the housing member 140 is described above. It's like a bar. And, the third and fourth driving magnets (not shown) that can be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed in the through-holes for the third and fourth magnets (not shown), respectively. ) may have the same size and the same shape as each other, and may be formed to have a lateral length smaller than that of the first driving magnet 131 and the second driving magnet 132 .

Here, like the first and second magnet through-holes 141a and 141a ′, the third and fourth magnet through-holes may be symmetrically disposed on a straight line with respect to the center of the housing member 140 . That is, the third and fourth driving magnets (not shown) may be symmetrically disposed on a straight line with respect to the center or the center of the housing member 140 .

If the first and second driving magnets 131 and 132 or the third and fourth driving magnets are disposed to face each other while being biased to one side regardless of the center of the housing member 140, the bobbin 110 Since the electromagnetic force acts on the first coil 120 to be biased to one side, there may be a possibility that the bobbin 110 is tilted. In other words, similarly to the first and second driving magnets 131 and 132 , the third and fourth driving magnets are symmetrically disposed on a straight line with respect to the center of the housing member 140 , so that the bobbin 110 . And by applying an unbiased electromagnetic force to the first coil 120 , it is possible to guide the bobbin 110 to move in the first direction easily and accurately.

Hereinafter, for convenience of description, it is assumed that the lens driving apparatus 100 according to the embodiment has only the first and second driving magnets 131 and 132 , but even when further including the third and fourth driving magnets, the following The description of can be applied.

A plurality of first stoppers 143 may protrude from the upper surface of the housing member 140 . The first stopper 143 is for preventing collision between the cover can 102 and the housing member 140 body, and when an external shock occurs, the upper surface of the housing member 140 is placed on the upper inner surface of the cover can 102 . Direct collisions can be avoided. In addition, the first stopper 143 may also serve to guide the installation position of the upper elastic member 150 . For example, referring to FIGS. 3 and 7 , a guide groove 155 having a shape corresponding to a position corresponding to that of the first stopper 143 may be formed in the upper elastic member 150 .

In addition, a plurality of upper frame support protrusions 144 in which the outer frame 152 of the upper elastic member 150 is inserted, seated, contacted, fixed, temporarily fixed, coupled, supported, or disposed on the upper side of the housing member 140 . may be formed to protrude. A first through hole (or groove) 152a having a corresponding shape may be formed in the outer frame 152 of the upper elastic member 150 corresponding to the upper frame support protrusion 144 . The upper frame support protrusion 144 may be fixed with an adhesive or fusion after being inserted, seated, contacted, fixed, temporarily fixed, combined, supported, or disposed in the first through hole 152a, and the fusion is thermal fusion or ultrasonic fusion. and the like.

In addition, a plurality of lower frame support protrusions 147 to which the outer frame 162 of the lower elastic member 160 is coupled may protrude below the housing member 140 . The lower frame support protrusion 147 may be formed at four lower corners of the housing member 140 , respectively. On the other hand, referring to FIG. 8 , the outer frame 162 of the lower elastic member 160 at a position corresponding to the lower frame support protrusion 147 is mounted, inserted, seated, contacted, coupled to the lower frame support protrusion 147 . , fixed, temporarily fixed, supported, or a fastening portion 162a that may be disposed may be formed, which may be fixed by an adhesive or fusion bonding, and the fusion may include thermal fusion or ultrasonic fusion.

Also, the housing member 140 may be a yoke housing member capable of performing a yoke function. In the structure of the yoke housing member, the structure may be formed to be spaced apart from the inner surface of the upper elastic member 140 and the upper surface of the yoke. This is to prevent the movement of the bobbin 110 in the upward direction and interference with the yoke.

Alternatively, the yoke (not shown) itself may serve as the housing member 140 . In this case, the yoke may be coupled to the base 190 , and the upper elastic member 150 may be disposed under the yoke or inside the yoke.

According to another embodiment, a separate cover may be further disposed on the upper portion of the yoke. In this case, the upper elastic member 150 may be disposed on the yoke or between the yoke and the cover, and the upper elastic member 150 may be coupled to the cover or the yoke.

Meanwhile, the driving magnets 130: 131 and 132 may be fixed to the magnet through-holes 141a and 141a' with an adhesive, but the present invention is not limited thereto, and an adhesive member such as a double-sided tape may be used. Alternatively, as a modified embodiment, a concave-shaped magnet seating portion (not shown) may be formed on the inner surface of the housing member 140 instead of the through-holes 141a and 141a ′ for the first and second magnets, unlike shown in the drawings. In addition, the magnet seating portion may have a size and shape corresponding to the size and shape of the driving magnet 130 .

The driving magnet 130 may be installed at a position facing the first coil 120 located on the outer peripheral surface of the bobbin 110 . In addition, the driving magnet 130 may be configured separately as shown, or may be configured as a single body as shown. In an embodiment, the driving magnet 130 may be disposed such that the surface facing the first coil 120 of the bobbin 110 is the N pole and the outer surface is the S pole. However, the present invention is not limited thereto, and the reverse configuration is also possible.

In addition, the driving magnet 130 may be configured to be divided into two planes perpendicular to the optical axis. That is, the driving magnet 130 is a positively polarized magnet, and is composed of a first magnet (not shown) and a second magnet (not shown) disposed to face each other with a non-magnetic barrier rib interposed therebetween in a plane perpendicular to the optical axis. can Here, the non-magnetic barrier rib may be air or a non-magnetic material. The first and second magnets may be disposed to have opposite polarities, but embodiments are not limited thereto and may have various shapes.

The first and second driving magnets 131 and 132 have a rectangular parallelepiped shape having a predetermined width, and are seated in the first and second through-holes 141a and 141a' for the first and second driving magnets, respectively. A wide surface or a partial surface of the magnets 131 and 132 may form a part of the side surface (outer surface or inner surface) of the housing member 140 . In addition, the first and second driving magnets 131 and 132 may be disposed on or coupled to the inner surface of the above-described yoke while being disposed on the side surface of the housing member 140 , and the inner surface of the yoke without the housing member 140 . It may be coupled or fixed to the side. In this case, the driving magnets 131 and 132 facing each other may be installed parallel to each other. In addition, the opposite surfaces of the driving magnet 130 and the first coil 120 of the bobbin 110 may be flatly disposed to be parallel to each other. However, the present invention is not limited thereto, and either one of the driving magnet 130 and the first coil 120 of the bobbin 110 may be flat, and the other may be configured as a curved surface, depending on the design. Alternatively, both the first coil 120 of the bobbin 110 and the opposite surface of the driving magnet 130 may be curved surfaces, and in this case, the first coil 120 of the bobbin 110 and the driving magnet 130 may be curved. ) may be formed to have the same curvature of opposite surfaces.

In addition, as described above, one side of the housing member 140 is provided with a through-hole (141b) or a groove for the sensor, and the position sensing unit 180 is mounted, inserted, and installed in the through-hole (141b) or groove for the sensor. Seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed, and the position sensing unit 180 may be electrically coupled to one surface of the first circuit board 170 by soldering or a soldering method. In other words, the first circuit board 170 is mounted, inserted, seated, contacted, coupled to the outer surface of one side provided with the sensor through hole 141b or groove among the four side surfaces 141 of the housing member 140 . , fixed, temporarily fixed, supported, or disposed.

The position sensing unit 180 may sense/determine the position of the bobbin 110 in the first direction together with a sensing magnet 182 to be described later. To this end, the position sensing unit 180 and the sensor through-hole 141b or groove may be disposed at a position corresponding to the position of the sensing magnet 182 . As shown, the sensing magnet 182 may be divided into upper and lower two to increase the strength of the magnetic field, but the embodiment is not limited thereto.

The position detecting unit 180 may be a sensor detecting a change in magnetic force emitted from the sensing magnet 182 of the bobbin 110 . For example, the position sensor 180 may be a Hall sensor, but the embodiment is not limited thereto. According to another embodiment, any sensor capable of detecting a change in magnetic force other than a Hall sensor may be used as the position detecting unit 180, and any sensor capable of detecting a position other than magnetic force is possible, yes For example, a method using a photoreflector or the like is also possible. When the position detecting unit 180 is implemented as a Hall sensor, calibration of the actuator driving distance may be additionally performed based on the Hall voltage difference with respect to the change in the magnet flux (ie, magnetic flux density) detected by the Hall sensor. .

For example, when the position sensor 180 is implemented as a Hall sensor, the Hall sensor 180 may have a plurality of pins. For example, the plurality of pins may include first and second pins. The first pin may include pins 1-1 and 1-2 respectively connected to voltage and ground, and the second pin may include pins 2-1 and 2-2 for outputting a sensed result. can Here, the sensed result output through the 2-1 and 2-2 pins may be in the form of a current, but the embodiment is not limited to the form of a signal. The first circuit board 170 is connected to the Hall sensor 180 to supply power to the 1-1 and 1-2 pins and to receive signals from the 2-1 and 2-2 pins. can

The first circuit board 170 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on one side of the housing member 140 . In this case, the installation position of the first circuit board 170 may be guided by the mounting protrusion 149 formed on one side of the housing member 140 as described above. One or a plurality of mounting protrusions 149 may be formed, and when two or more are formed, it may be easier to guide the arrangement position of the first circuit board 170 .

In addition, the first circuit board 170 is provided with a plurality of terminals 171 , and may supply current required by the first coil 120 and the position sensing unit 180 of the bobbin 110 by receiving external power. . The number of terminals 171 formed on the first circuit board 170 may be increased or decreased according to the types of components that need to be controlled.

Also, referring to FIGS. 3 and 6 , at least one pin 172 may be provided on the first circuit board 170 . As shown, there may be four pins 172, but the number of pins 172 may be more or less than four. For example, the four pins 172 may be a test pin, a hole pin, a VCM+ pin, and a VCM- pin, but the embodiment is not limited to the type of these pins. Here, the test pin may be a pin used to evaluate the performance of the lens driving apparatuses 100A and 100B. The hole pin may be a pin used to retrieve data output from the position sensing unit 180 . The VCM+ pin and the VCM- pin may be pins used to evaluate the performance of the lens driving apparatuses 100A and 100B without receiving feedback from the position sensing unit 180 .

According to an embodiment, the first circuit board 170 may be provided as a flexible printed circuit board (FPCB). The first circuit board 170 may include a focus control unit 300 to be described later. For example, the focus controller 300 may receive signals from pins 2-1 and 2-2 of the hall sensor 180 as location information. The focus control unit 300 may be mounted on the first circuit board 170 . Alternatively, according to another embodiment, the focus control unit 300 may not be mounted on the first circuit board 170 but may be mounted on a separate board. Here, the other separate board may be a second circuit board (not shown) on which an image sensor (not shown) is mounted in the camera module, or may be a separate board.

In addition, in the above example, the first circuit board 170 has been described as being mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the outer surface of the housing member 140 , but in the embodiment is not limited thereto. That is, according to another embodiment, the first circuit board 170 may be positioned under the housing member 140 instead of the outer surface of the housing member 140 .

According to an embodiment, the cover can 102 may be a yoke cover can capable of performing a yoke function. In addition, the cover can 102a may be formed of a sus material, a magnetic material, or a metal material, but is not limited thereto, and any material having electrical conductivity may be used.

According to another embodiment, although not shown, the lens driving apparatus 100 may further include a cover. The cover may be wrapped by the cover can 102 and support the bobbin 110 in a fixed manner. The driving magnet 130 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed inside the cover.

9 is a plan perspective view showing the bobbin 110 shown in FIG. 2 according to an embodiment, and FIG. 10 is a bottom perspective view showing the bobbin 110 shown in FIG. 2 according to an embodiment.

4 and 5 and 7 to 10 , the upper elastic member 150 and the lower elastic member 160 may elastically support the ascending and/or descending operation of the bobbin 110 in the optical axis direction. . The upper elastic member 150 and the lower elastic member 160 may be provided as a leaf spring, but the embodiment is not limited to the shape of each of the upper and lower elastic members 150 and 160 .

The upper elastic member 150 includes an inner frame 151 coupled to the bobbin 110 , an outer frame 152 coupled to the housing member 140 , and a connector connecting the inner frame 151 and the outer frame 152 . (153) may be included.

In addition, the lower elastic member 160 connects the inner frame 161 coupled to the bobbin 110 and the outer frame 162 coupled to the housing member 140 , and the inner frame 161 and the outer frame 162 . It may include a connection part 163 to

The connecting portions 153 and 163 may be bent at least once to form a pattern having a predetermined shape. The bobbin 110 may be elastically (or elastically) supported by the ascending and/or descending operation in the first direction, which is the optical axis direction, through a change in the position of the connection parts 153 and 163 and micro-deformation.

According to an embodiment, as shown in FIG. 7 , the upper elastic member 150 includes a plurality of first through-holes 152a in the outer frame 152 , and a plurality of second through-holes in the inner frame 151 . (151a) may be included.

The first through hole 152a is coupled to the upper frame support protrusion 144 formed on the upper surface of the housing member 140 , and the second through hole 151a is the upper support protrusion 113 formed on the upper surface of the bobbin 110 . can be combined with The upper support protrusion 113 will be described in detail later. That is, the outer frame 152 is mounted, seated, contacted, fixed, temporarily fixed, supported, disposed, or coupled to the housing member 140 through the first through hole 152a, and the inner frame 151 has the second through hole. It may be mounted, seated, contacted, fixed, temporarily fixed, supported, disposed, or coupled to the bobbin 110 through (151a).

The connection part 153 of the upper elastic member 150 connects the inner frame 151 and the outer frame 152 so that the inner frame 151 is elastically deformable within a predetermined range with respect to the outer frame 152 in the first direction. can

At least one of the inner frame 151 and the outer frame 152 of the upper elastic member 150 has a terminal part electrically connected to at least one of the first coil 120 of the bobbin 110 or the first circuit board 170 . It may include at least one or more.

Referring to FIG. 8 , the lower elastic member 160 includes a plurality of fastening portions 162a in the outer frame 162 , and a plurality of third through holes (or grooves) 161a in the inner frame 161 . may include

As described above, the fastening portion 162a may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the lower surface of the housing member 140, and the third through hole 161a is The lower support protrusion 114 formed on the lower surface of the bobbin 110 shown in FIG. 14 may be in contact, coupled, fixed, or temporarily fixed. That is, the outer frame 162 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the housing member 140 through the fastening portion 162a, and the inner frame 161 is It may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the bobbin 110 through the third through hole 161a.

The connection part 163 of the lower elastic member 160 connects the inner frame 161 and the outer frame 162 so that the inner frame 161 is elastically deformable within a predetermined range with respect to the outer frame 162 in the first direction. can

The lower elastic member 160 may include a first lower elastic member 160a and a second lower elastic member 160b separated from each other. Through this two-part structure, the first lower elastic member 160a and the second lower elastic member 160b of the lower elastic member 160 may receive power of different polarities or different currents. That is, after the inner frame 161 and the outer frame 162 are coupled to the bobbin 110 and the housing member 140 , respectively, the inner frame corresponding to both ends of the first coil 120 disposed on the bobbin 110 . By providing a solder portion at the position of the frame 161, the solder portion may be applied with power of different polarities or different currents by performing conductive connection such as soldering in the solder portion. In addition, the first lower elastic member 160a is electrically connected to one of both ends of the first coil 120 , and the other one of the both ends of the first coil 120 and the second lower elastic member 160b are connected to each other. It may be electrically connected to receive current and/or voltage from the outside. To this end, at least one of the inner frame 161 and the outer frame 162 of the lower elastic member 160 is electrically connected to at least one of the first coil 120 or the first circuit board 170 of the bobbin 110 . It may include at least one terminal unit connected to the Both ends of the first coil 120 may be disposed opposite to each other with respect to the bobbin 110 , or may be disposed adjacent to each other on the same side.

Meanwhile, the upper elastic member 150 and the lower elastic member 160 , the bobbin 110 and the housing member 140 may be assembled through thermal fusion and/or bonding using an adhesive or the like. At this time, according to the assembly sequence, the fixing operation can be finished by bonding using an adhesive after fixing by thermal fusion.

As another embodiment, the upper elastic member 150 may be configured in a two-part structure as illustrated in FIG. 8 , and the lower elastic member 160 may be configured in an integrated structure as illustrated in FIG. 7 .

11 is an exploded perspective view of the bobbin 110, the first coil 120, the position sensing unit 180, and the sensing magnet 182 according to an embodiment, and FIG. 12 is the bobbin 110 according to the embodiment. ), the first coil 120 , the first and second driving magnets 131 and 132 , the position sensing unit 180 , and a schematic bottom perspective view of the sensing magnet 182 .

The bobbin 110 may be installed in the inner space of the housing member 140 to be reciprocally movable in the optical axis direction. The first coil 120 is installed on the outer peripheral surface of the bobbin 110 to electromagnetically interact with the driving magnet 130 of the housing member 140 to reciprocate the bobbin 110 in the first direction.

In addition, the bobbin 110 is elastically (or elastically) by the upper elastic member 150 and the lower elastic member 160 so that the bobbin 110 moves in the first direction, which is the optical axis direction, to perform the autofocus function. ) can be supported.

Although not shown in the bobbin 110, at least one lens may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed therein. For example, the bobbin 110 may include an installed lens barrel (not shown). The lens barrel is a component of a camera module to be described later and may not be an essential component of the lens driving apparatus 100 . The lens barrel may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the inside of the bobbin 110 in various ways. For example, a female thread may be formed on the inner peripheral surface of the bobbin 110 , and a male thread corresponding to the female thread may be formed on the outer peripheral surface of the lens barrel, and the lens barrel may be coupled to the bobbin 110 by screwing them. However, this is not limited thereto, and the lens barrel may be directly fixed to the inside of the bobbin 110 by a method other than screwing, without forming a screw thread on the inner circumferential surface of the bobbin 110 .

Alternatively, one or more lenses may be integrally formed with the bobbin 110 without a lens barrel. The lens coupled to the lens barrel may be configured as one sheet, or two or more lenses may be configured to form an optical system.

In addition, a plurality of upper support protrusions 113 and a plurality of lower support protrusions 114 may respectively protrude from the upper and lower surfaces of the bobbin 110 . The upper support protrusion 113 may be provided in a cylindrical or prismatic shape, as shown in FIG. 9 , and couple, fix, and temporarily fix the inner frame 151 and the bobbin 110 of the upper elastic member 150 . , contact, or support. According to an embodiment, the second through hole 151a may be formed at a position corresponding to the upper support protrusion 113 of the inner frame 151 of the upper elastic member 150 . In this case, the upper support protrusion 113 and the second through hole 151a may be fixed by thermal fusion, or may be fixed with an adhesive member such as epoxy. In addition, a plurality of upper support protrusions 113 may be provided. In this case, the distance between each of the upper support protrusions 113 may be appropriately arranged within a range that can avoid interference with surrounding components. That is, each of the upper support protrusions 113 may be arranged at regular intervals symmetrically with respect to the center of the bobbin 110 , and their intervals are not constant, but on a specific virtual line passing through the center of the bobbin 110 . It may be formed to be symmetrical with respect to

As shown in FIG. 10 , the lower support protrusion 114 may be provided in a cylindrical or prismatic shape like the upper support protrusion 113 , and the inner frame 161 and the bobbin 110 of the lower elastic member 160 . may be coupled, fixed, temporarily fixed, contacted, or supported. According to an embodiment, a third through hole 161a may be formed at a position corresponding to the lower support protrusion 114 of the inner frame 161 of the lower elastic member 160 . In this case, the lower support protrusion 114 and the third through hole 161a may be fixed by thermal fusion, or may be fixed with an adhesive member such as epoxy. In addition, a plurality of lower support protrusions 114 as shown in FIG. 10 may be provided. In this case, the distance between each of the lower support protrusions 114 may be appropriately arranged within a range that can avoid interference with surrounding components. That is, each of the lower support protrusions 114 may be arranged at regular intervals symmetrically with respect to the center of the bobbin 110 .

In addition, on the upper and lower surfaces of the bobbin 110 , the upper escape groove 112 and the lower side are located at positions corresponding to the connection part 153 of the upper elastic member 150 and the connection part 163 of the lower elastic member 160 . Evacuation grooves 118 may be formed, respectively.

Since the upper escape groove 112 and the lower escape groove 118 are provided, spatial interference between the connection parts 153 and 163 and the bobbin 110 when the bobbin 110 moves in the first direction with respect to the housing member 140 This can be removed to make it easier to elastically deform the connection parts 153 and 163 . In addition, the location of the upper escape groove 112 may be disposed at the corner of the housing member 140 as illustrated in FIG. 9 , but may be disposed on the side according to the shape and/or position of the connection part of the elastic member.

In addition, on the outer peripheral surface of the bobbin 110, a seating groove 116 for a coil in which the first coil 120 is mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed may be provided, Examples are not limited thereto. That is, according to another embodiment, the first coil 120 is directly mounted on the outer circumferential surface of the bobbin 110, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or instead of being disposed, the bobbin 110 A coil ring (not shown) having the same shape as the outer circumferential shape of the bobbin 110 is mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed adjacent to the outer circumferential surface of the bobbin 110, the first coil 120 ) may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the coil ring.

The first coil 120 is to be provided as a ring-shaped coil block mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the outer peripheral surface of the bobbin 110 or the seating groove 116 for the coil. However, the present invention is not limited thereto, and the first coil 120 may be directly wound on the outer circumferential surface of the bobbin 110 or the coil seating groove 116 . When the pre-wound first coil 120 is mounted, inserted, or disposed, it may be mounted, inserted, or disposed from the upper or lower portion of the bobbin 110 .

According to an embodiment, the first coil 120 may be formed in an approximately octagonal shape as shown in FIG. 11 . This is a shape corresponding to the shape of the outer peripheral surface of the bobbin 110, and the bobbin 110 may also have an octagonal shape. In addition, at least four surfaces of the first coil 120 may be provided in a straight line, and a corner portion connecting these surfaces may be implemented as a round or a straight line. In this case, the portion formed in a straight line may be a surface corresponding to the driving magnet 130 . Also, a surface of the driving magnet 130 corresponding to the first coil 120 may have the same curvature as that of the first coil 120 . That is, if the first coil 120 is a straight line, the corresponding driving magnet 130 may have a straight line. If the first coil 120 is curved, the corresponding driving magnet 130 may have a curved surface. , and may also have the same curvature. In addition, even if the first coil 120 is curved, the corresponding driving magnet 130 may have a straight surface, or vice versa.

The first coil 120 is for moving the bobbin 110 in the optical axis direction when performing the auto-focus function, and when current is supplied, it can electromagnetically interact with the driving magnet 130 to form an electromagnetic force, As described above, the formed electromagnetic force can move and move the bobbin 110 .

On the other hand, the first coil 120 may be configured to correspond to the driving magnet 130 . As shown, the driving magnet 130 is configured as a single body so that the entire surface facing the first coil 120 . When is provided to have the same polarity, the surface corresponding to the first coil 120 and the driving magnet 130 may also be configured to have the same polarity. On the other hand, although not shown, if the driving magnet 130 is divided into two planes perpendicular to the optical axis so that the surface facing the first coil 120 is divided into two or more, the first coil 120 It is also possible to be divided into a number corresponding to the divided driving magnet 130 .

Meanwhile, the lens driving device 100 may further include a sensing magnet 182 . The sensing magnet 182 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the bobbin 110 . For this reason, the sensing magnet 182 may move in the first direction by the same amount of displacement as the bobbin 110 when the bobbin 110 moves in the first direction. In addition, the sensing magnet 182 may be integrally configured with the bobbin 110 , and may be disposed such that an upper direction of the bobbin 110 is an N pole and a lower direction of the bobbin 110 is an S pole. However, the present invention is not limited thereto, and the reverse configuration is also possible.

Also, the sensing magnet 182 may be divided into two in a plane perpendicular to the optical axis. 9 to 12 , the bobbin 110 may further include a receiving groove 117 for accommodating the sensing magnet 182 on the outer peripheral surface of the bobbin 110 .

The receiving groove 117 may be formed in an inner direction of the bobbin 110 to a predetermined depth from the outer surface of the bobbin 110 . Specifically, the receiving groove 117 may be formed on one side of the bobbin 110 so that at least a portion of the receiving groove 117 is located inside the first coil 120 .

In addition, at least a portion of the receiving groove 117 may be concave to a predetermined depth in the inner direction of the bobbin 110 more than the coil seating groove 116 . In this way, by forming the accommodating groove 117 in the inner direction of the bobbin 110, the sensing magnet 182 can be accommodated in the bobbin 110, whereby a separate sensing magnet 182 for the sensing magnet 182 can be accommodated. Since there is no need to secure an installation space, the space efficiency of the bobbin 110 can be improved.

In particular, the receiving groove 117 may be disposed at a position corresponding to the position of the position sensing unit 180 of the housing member 140 or at a position opposite to the position sensing unit 180 . For this reason, the position detecting unit 180 and the sensing magnet 182 may be aligned on the same axis.

The distance d between the sensing magnet 182 and the position sensing unit 180 can be minimized as the thickness of the first coil 120 and the separation distance between the first coil 120 and the position sensing unit 180 . Therefore, the magnetic force detection accuracy of the position sensing unit 180 can be improved.

More specifically, as illustrated in FIGS. 9 to 12 , the receiving groove 117 has an inner surface on which one surface of the sensing magnet 182 is supported, and a predetermined depth more inside than the inner surface so that an adhesive can be injected. It may include an adhesive groove 117b concave with the .

The inner surface is one surface positioned in the inner direction toward the center of the bobbin 110, and when the sensing magnet 182 has a rectangular parallelepiped shape, the wide surface of the sensing magnet 182 is contacted or seated.

The bonding groove 117b may be a groove formed so that a portion of the inner surface is concave deeper in the inner direction toward the center of the bobbin 110 . The adhesive groove 117b may be formed up to the inner surface of the bobbin 110 on which one surface of the sensing magnet 182 is mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported or disposed.

As another embodiment, the receiving groove 117 has an outer peripheral surface (ie, a coil seating groove 116 ) on which the second coil 120 is provided from an inner surface on which one surface (ie, a wide surface) of the sensing magnet 182 is supported. ) surface) may be less than or equal to the thickness of the sensing magnet 182 . For this reason, the sensing magnet 182 may be fixed in the receiving groove 117 by the inner pressing force of the first coil 120 due to the winding of the first coil 120 . In this case, it may not be necessary to use an adhesive.

As a further embodiment, although not shown in the drawings, the bobbin 110 is positioned symmetrically with the receiving groove 117 with respect to the center of the bobbin 110 on the outer circumferential surface facing the outer circumferential surface where the receiving groove 117 is formed. 110) may further include an additional accommodating groove formed on the outer circumferential surface, and a weight balancing member accommodated in the additional accommodating groove.

According to an embodiment, the sensing magnet 182 may be omitted. In this case, the driving magnet 130 may be used instead of the sensing magnet 182 .

In addition, according to the embodiment, the distance between the sensing magnet 182 provided on the bobbin 110 as a moving body and the position sensing unit 180 provided on the housing member 140 as a fixed body can be minimized, so that the lens Since the amount of displacement in the optical axis direction can be detected more accurately, the lens can be more accurately positioned at the focal length of the lens.

In addition, in the embodiment, the sensing magnet 182 is mounted, seated, contacted, fixed, temporarily fixed, coupled, supported, or disposed inside the bobbin 110 , and the position sensing unit 180 is installed inside the housing member 140 . By mounting, seating, contacting, fixing, temporarily fixing, combining, supporting, or disposing on the camera module, space efficiency of the camera module (particularly, bobbin) is improved because a separate space for mounting the position sensing unit 180 is not required. can do it

The camera module of the embodiment includes, in addition to the above-described lens driving device 100 , a lens mounted, inserted, seated, contacted, coupled, fixed, supported or disposed in the lens driving device 100 , and an image sensor (not shown) at the bottom , a second circuit board (not shown) on which the image sensor is disposed (or a main circuit board) and an optical system may be further included. In this case, the camera module according to the embodiment may further include a lens barrel coupled to the bobbin 110 .

The lens barrel may be the same as described above, and the second circuit board may form a bottom surface of the camera module from a portion on which the image sensor is mounted. In addition, the optical system may include at least one or more lenses that transmit an image to the image sensor.

Meanwhile, an actuator module capable of performing an auto-focus function and an image stabilization function may be installed in the optical system. The actuator module performing the auto-focus function may be configured in various ways, and a voice coil unit motor is generally used a lot. The lens driving apparatus 100 according to the above-described embodiment may correspond to an actuator module that performs an auto-focus function under the control of the focus controller 300 . However, the embodiment is not limited to the actuator module performing the auto-focus function, and may also be applied to the actuator module performing both the auto-focus function and the hand-shake correction function.

Although not shown, when adding a second coil (not shown), a support member (not shown), and a plurality of sensing units (not shown) to the lens driving device 100 for performing the aforementioned autofocus function, The lens driving device 100 may perform an auto-focus function as well as a hand-shake correction function. Here, the second coil may be disposed to face the driving magnet. That is, the second coil is disposed so that the bottom surface of the driving magnet 130 directly faces the second coil, and each of the plurality of sensing units may be implemented as, for example, a Hall sensor, and each of the plurality of sensing units and the second coil are disposed. The two coils and the driving magnet may be disposed on the same axis. Accordingly, the second coil may perform handshake correction by moving the housing member 140 on which the bobbin 110 is mounted in the second and/or third directions through interaction with the driving magnet 130 .

In this case, a support member may be disposed on the upper surface of the base 190 to elastically (or elastically) support the horizontal operation of the housing member 140 moving in a direction perpendicular to the first direction.

In addition, the camera module may further include an infrared cut filter (not shown). The infrared cut filter serves to block light in the infrared region from being incident on the image sensor. In this case, in the base 190 illustrated in FIG. 2 , an infrared cut filter may be installed at a position corresponding to the image sensor, and may be coupled to a holder member (not shown). In addition, the base 190 may support the lower side of the holder member.

A separate terminal member may be installed in the base 190 to conduct electricity with the second circuit board, and it is also possible to integrally form the terminal using a surface electrode or the like. Meanwhile, the base 190 may function as a sensor holder to protect the image sensor, and in this case, a protrusion may be formed in a downward direction along the side surface of the base 190 . However, this is not an essential configuration, and although not shown, a separate sensor holder may be disposed under the base 190 to perform its role.

Hereinafter, the configuration and operation of the focus control unit 300 will be described with reference to FIGS. 13 to 17 attached thereto. For convenience, the focus control unit 300 will be described with reference to the aforementioned lens driving device 100 , but the embodiment is not limited thereto. That is, of course, the focus control unit 300 according to the embodiment may be applied to a lens driving device having a configuration different from that of the above-described lens driving device 100 to perform an autofocus function. That is, as long as the lens driving device can move the bobbin 110 in the optical axis direction by the interaction of the first coil 120 and the driving magnet 130 , it is applied to the lens driving device having any configuration, and the focus control unit 300 may perform an auto-focus function.

13 is a flowchart for explaining an auto-focus function (or a method of performing an auto-focus function) 200 performed by the focus control unit 300 of a camera module according to an embodiment, and FIG. 14 is an embodiment. shows a block diagram of the focus control unit 300 by

13 and 14, the focus control unit 300 controls the interaction between the first coil 120 and the driving magnet 130 according to the subject information and the position information output from the position detection unit 180, , the autofocus function may be performed by moving the bobbin 110 by the first movement amount (or the first displacement amount) in the first direction parallel to the optical axis. To this end, the focus control unit 300 may include an information receiving unit 310 , a bobbin position searching unit 320 , and a movement amount adjusting unit 330 .

The position detecting unit 180 may detect the position of the bobbin 110 in the optical axis direction, and output the sensed result to the movement amount adjusting unit 330 as position information.

The information receiving unit 310 may receive subject information through the input terminal IN1 (step 210). Here, the subject information may include at least one of a distance between a subject and at least one lens (not shown), a distance between the subject and an image sensor, a position of the subject, and a phase of the subject. The subject information may be obtained in various ways.

According to an embodiment, subject information may be acquired using two cameras.

According to another embodiment, subject information may be obtained using a laser. For example, in Korea Publication No. 1989-0008573, a method of measuring the distance of an object using a laser is disclosed.

According to another embodiment, subject information may be obtained using a sensor. For example, in US Patent Publication No. US2013/0033572 filed by Sony, a method of obtaining a distance between a camera and a subject using an easy sensor is disclosed.

The above-described subject information may be provided, received, or accepted from the outside of the camera module to the camera module. For example, when the camera module according to the embodiment is applied to a mobile terminal (or a portable terminal), subject information may be obtained from the mobile terminal, and the obtained subject information may be provided to the focus controller 300 of the camera module. . In this case, the subject information may be provided to the information receiver 310 from the image sensor of the camera module. That is, the image sensor may provide subject information to the information receiver 310 of the focus controller 300 . However, according to another embodiment, the above-described subject information may be obtained from the camera module according to the embodiment.

After operation 210 , the bobbin position search unit 320 may find a position of the bobbin 110 in focus corresponding to the subject information received from the information receiving unit 310 (operation 220 ). To this end, for example, the bobbin position search unit 320 may include a data extractor 322 and a look-up table (LUT) 324 .

The look-up table 324 may map and store the position of the bobbin 110 in which the focus is obtained for each subject information. For example, the position of the bobbin 110 that is in focus for each distance between the subject and the lens may be obtained in advance and stored in the form of the look-up table 324 . That is, before moving the bobbin 110 by the first movement amount in step 230 , the look-up table 324 may be previously generated using the position detecting unit 180 . For example, the position of the bobbin 110 for each subject information may be calculated in advance based on the current change value sensed by the position detecting unit 180 . Accordingly, the look-up table 324 may be generated by measuring the position of the bobbin 110 when the focus is achieved for each subject information that is the distance between the subject and the lens. Also, the look-up table 324 may code and store the position of the bobbin 110 .

The data extracting unit 322 receives the subject information received from the information receiving unit 310 , extracts the position of the bobbin 110 in focus corresponding to the subject information from the lookup table 324 , and the extracted bobbin 110 . ) may be output to the movement amount adjusting unit 330 . As described above, when the position of the bobbin 110 is coded and stored in the lookup table 324 , the data extractor 322 may find a code value corresponding to the subject information in the lookup table 324 . .

After operation 220 , the movement amount adjusting unit 330 may move the bobbin 110 by a first movement amount (or a first displacement amount) to the position found by the bobbin position search unit 320 (operation 230 ). In this case, when performing step 230 , the movement amount adjusting unit 330 may refer to the position information output from the position sensing unit 180 and received through the input terminal IN2 . That is, the current position of the bobbin 110 may be determined based on the position information provided from the position sensing unit 180 , and the bobbin 110 may be moved to a corresponding position based on the identified current position of the bobbin 110 . .

For example, the movement amount adjusting unit 330 may adjust the amount of current applied to the first coil 120 to move the bobbin 110 in the first direction by the first movement amount. To this end, the amount of current for each position of the bobbin 110 may be determined in advance.

For example, in the sensing magnet 182 according to the first direction movement of the sensing magnet 182 fixedly coupled to the bobbin 110, which is a movable body, in which the position detecting unit 180 fixedly coupled to the housing member 140 moves in the first direction. Detect changes in the emitted magnetic force. At this time, the current change amount output based on the magnetic force change amount sensed by the position sensor 180 is received and checked as location information, and based on this, the movement amount adjusting unit 330 calculates or determines the current position of the bobbin 110 . In this way, it is possible to determine the amount of applied current for moving the bobbin 110 to the focused position by the first movement amount by referring to the calculated or determined current position of the bobbin 110 .

15 (a) and (b) are graphs for explaining an auto-focus function according to a comparative example. In Fig. 15 (a), the horizontal axis represents the focus value, the vertical axis represents the displacement, and in Fig. 15 (b), the horizontal axis is Current (or time) is represented, and the vertical axis is displacement (or code).

16 (a) and (b) are graphs for explaining the auto-focus function according to the embodiment. In Fig. 16 (a), the horizontal axis represents the focus value, the vertical axis represents the displacement, and in Fig. 16 (b), the horizontal axis is Current (or time) is represented, and the vertical axis is displacement (or code).

15 (a) and (b), from the first reference focal length (Infinity) at the position furthest from the lens and the image sensor to the second reference focal length (Macro) at the position closest to the lens and the image sensor The position (or displacement) 400 of the bobbin 110 in which the focus is best is found while increasing the current to . The bobbin 110 may not be driven during the initial predetermined time P when the current is applied. Thereafter, the displacement of the bobbin 110 increases as the current 402 (or the code value 404 corresponding to the change amount of the magnetic force sensed by the position sensing unit 180) continues to increase. In the case of the comparative example, after moving the bobbin 110 from the first reference focal length to the second reference focal length, the position 400 of the bobbin 110 that has the best focus is found, so it may take a lot of time.

On the other hand, referring to FIGS. 16 (a) and 16 (b), the code for the position of the bobbin 110 at which the lens is focused is found in the look-up table 324 using subject information, and based on this, the bobbin 110 ) may be immediately moved 410 to the focal position (or displacement). Accordingly, it can be seen that the time required for focusing the lens is reduced as compared with the above-described comparative example.

Again, referring to FIG. 13 , after focusing the lens through the aforementioned steps 210 to 230, the lens may be finely focused (steps 240 to 260).

After performing step 230 in which the bobbin 110 is moved by the first movement amount, the focus control unit 300 moves the bobbin 110 within a range of a second movement amount smaller than the first movement amount, thereby moving the frequency modulation transfer function (MTF). : The focus position 400 of the bobbin 110 showing the largest value among the Modulation Transfer function values may be found (step 240). Here, the MTF value may be a numerical value of the resolution.

After step 240, the focus control unit 300 determines whether the bobbin 110 has been moved for a predetermined period to find the largest MTF value (step 250). Alternatively, in order to find the largest MTF value, the initializing control unit 300 may determine whether the bobbin 110 has been moved a predetermined number of times (step 250). Alternatively, the bobbin 110 may be continuously moved over a predetermined period or a predetermined number of times until the largest MTF value is found.

If it is determined that the bobbin 110 has been moved for a predetermined period or a predetermined number of times, the position of the bobbin 110 showing the largest MTF value is finally determined as the final focal position where the lens is in focus (step 260).

17 (a) and (b) are graphs for explaining fine adjustment in the auto focus function according to the embodiment. In FIG. 17 (a), the horizontal axis indicates the focus value, the vertical axis indicates the displacement, and FIG. 17 (b) In , the horizontal axis represents current (or time), and the vertical axis represents displacement (or code).

17 (a) and (b), after performing steps 210 to 230 to primarily focus the lens (410), then steps 240 to 260 to finely focus the lens. (420) can be.

By performing the above-described steps 240 to 260, the camera module according to the embodiment can improve the resolution by accurately focusing the lens.

In the above, the embodiment has been mainly described, but this is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are not exemplified above in the range that does not depart from the essential characteristics of the present embodiment. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

100: lens drive unit 102: cover can
104: first groove 106: third groove
110: bobbin 112: upper escape groove
118: lower escape groove 113: upper support projection
114: lower support protrusion 116: seating groove for coil
117: receiving groove 117b: adhesive groove
120: first coil 130, 131, 132: magnet for driving
140: housing member 141: side of the housing member
141a, 141a': through hole for magnet 141b: through hole for sensor
143: first stopper 144: upper frame support protrusion
147: lower frame support protrusion 148: lower guide groove
149: mounting projection 150: upper elastic member
151, 161: inner frame 151a: second through hole
152, 162: outer frame 153, 163: connection part
152a: first through hole 155: guide groove
160, 160a, 160b: lower elastic member 161a: third through hole
162a: fastening unit 170: first circuit board
171: terminal of the first circuit board 172: various pins
173: through hole for mounting 180: position sensing unit
182: sensing magnet 190: base
192: second groove 194: guide member
300: focus control unit 310: information receiving unit
320: bobbin position search unit 322: data extraction unit
324: look-up table 330: movement amount control unit

Claims (11)

At least one lens is mounted, the bobbin including a receiving groove;
a position detecting unit detecting the position of the bobbin in the optical axis direction and outputting it as position information;
a sensing magnet opposite to the position sensing unit and accommodated in the receiving groove of the bobbin;
a first coil and a driving magnet facing each other to move the bobbin in the optical axis direction of the lens; and
According to the given subject information and the location information, by controlling the interaction between the first coil and the driving magnet to move the bobbin by a first movement amount in a first direction parallel to the optical axis to perform an autofocus function a focus control,
The accommodating groove is formed in an inner direction of the bobbin, and is located inside the first coil. The camera module of claim 1 , wherein the subject information includes at least one of a distance between a subject and the at least one lens, a position of the subject, and a phase of the subject. According to claim 1, wherein the focus control unit
an information receiver configured to receive the subject information;
a bobbin position search unit that finds a position of the bobbin that is in focus corresponding to the received subject information; and
and a movement amount adjusting unit for moving the bobbin by the first movement amount to the found position based on the location information. The method of claim 3, wherein the bobbin position search unit
a look-up table for mapping and storing a position of the bobbin in focus corresponding to the subject information; and
and a data extractor configured to extract a position of the bobbin in focus corresponding to the received subject information from the look-up table. delete The camera module of claim 4 , wherein the look-up table is generated using the position sensor before moving the bobbin by the first movement amount. The method of claim 1, wherein the focus control unit moves the bobbin by the first movement amount and then moves the bobbin within a range of a second movement amount smaller than the first movement amount to obtain the largest value among the frequency modulation transfer function values. A camera module that finds the final focus position of the visible bobbin. The camera module of claim 7 , wherein the focus controller moves the bobbin for a predetermined period to find the largest value among the frequency modulation transfer function values. The camera module of claim 7 , wherein the focus controller moves the bobbin a predetermined number of times to find the largest value among the frequency modulation transfer function values. According to claim 1, wherein the camera module
Further comprising a second coil disposed to face the driving magnet,
The bobbin is movable in second and third directions orthogonal to the first direction by interaction between the second coil and the driving magnet. The camera module of claim 1 , further comprising an image sensor that receives the subject information from the outside and outputs it to the focus controller.

Images