Lens drive device and camera module

Abstract

To provide a lens drive device having a simple structure with fewer component counts and reducible in size, and a camera module including the lens drive device.SOLUTION: A lens drive device 1 comprises a lens holder 2, a housing 3 for accommodating the lens holder 2 in the inside, a support mechanism 4 for supporting the lens holder 2 so as to be capable of being driven in the optical axis direction of two optical systems 200, and a drive mechanism 5 including a coil 51 provided on the lens holder 2 and a magnet 52 provided on the housing 3, for providing drive power to drive the lens holder 2 in the optical axis direction. The lens holder 2 comprises a body unit 21, two openings 22 for respectively accommodating the two optical systems 200 in the inside, and an accommodation unit 23 for accommodating the support mechanism 4 in the inside and located between the two openings 22 and formed so as to penetrate the body unit 21 in the optical axis direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention generally relates to a lens driving device and a camera module, and more specifically, to a lens driving device configured to be capable of driving two optical systems using a driving mechanism composed of a coil and a magnet, and a camera module equipped with the lens driving device. [Background technology]

[0002] Conventionally, there is known a lens driving device for driving two optical systems arranged side by side. Such a lens driving device is very useful when it is necessary to drive two optical systems in a synchronized manner in order to measure the distance to a subject by stereo photography.

[0003] For example, Patent Document 1 discloses a lens driving device 500 shown in Fig. 1. The lens driving device 500 includes a housing 510 composed of a cover and a base, and an internal structure 520 housed inside the housing 510. As shown in Fig. 2, the internal structure 520 includes two lens holders 521 for holding two optical systems therein, two coils 522 fixed on the outer circumferential surfaces of the two lens holders 521, a magnet holder 523 that covers the two lens holders 521 and the two coils 522 from the outside, four magnets 524 held by the magnet holder 523 so as to be positioned outside the two coils 522, and a pair of leaf springs 525 that hold the two lens holders 521 so as to be vibrated in the optical axis direction of the two optical systems.

[0004] When a current flows through the coil 522, a driving force (Lorentz force) is generated that drives the lens holder 521, to which the coil 522 through which the current flows, in the optical axis direction, and the lens holder 521 can be driven in the optical axis direction. In addition, by controlling the current supplied to the two coils 522, the two lens holders 521 can be driven synchronously.

[0005] Meanwhile, with the recent miniaturization of camera modules, there is an increasing need to miniaturize lens driving devices. In order to miniaturize a lens driving device, it is preferable to reduce the number of components constituting the lens driving device. However, in the configuration of lens driving device 500 of Patent Document 1, two lens holders 521 are held so as to be vibrated up and down using a pair of leaf springs 525, and four magnets 524 need to be held by magnet holder 523, so that the number of components of lens driving device 500 cannot be reduced. Therefore, there is a need for a lens driving device that has a simple configuration with fewer components and can be miniaturized. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-175989 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in consideration of the above-mentioned problems in the conventional art, and has an object to provide a lens driving device that has a simple configuration with fewer parts and can be made compact, and a camera module equipped with the lens driving device. [Means for solving the problem]

[0008] Such an object can be achieved by the present invention as defined by the following (1) and (2).

[0009] (1) a lens holder for holding two optical systems; a housing for accommodating the lens holder therein; a support mechanism for supporting the lens holder in the housing so as to be drivable in the optical axis directions of the two optical systems; a driving mechanism including a coil provided on the lens holder and a magnet provided on the housing, the driving mechanism providing a driving force for driving the lens holder in the optical axis direction; The lens holder includes: A main body portion, two openings that penetrate the main body in the optical axis direction and are spaced apart from each other, and that house the two optical systems therein, respectively; A lens driving device characterized by comprising: a storage section located between the two openings, formed to penetrate the main body in the optical axis direction, and for storing the support mechanism therein.

[0010] (2) The lens driving device according to (1) above; and two optical systems held by the lens holder of the lens driving device. Effect of the Invention

[0011] In the lens driving device and camera module of the present invention, a support mechanism for supporting the lens holder holding two optical systems so that it can be driven in the optical axis direction of the two optical systems is stored in a storage section formed between the openings that respectively hold the two optical systems. Therefore, compared to the conventional technology in which the lens holder is supported so that it can be driven in the optical axis direction by a pair of leaf springs, the number of parts of the lens driving device can be reduced and the lens driving device can have a simpler configuration. In addition, since the support mechanism is stored in the storage section of the lens holder, the space in the housing can be effectively utilized and the lens driving device can be made smaller. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is an exploded perspective view of a lens driving device according to a related art; [Diagram 2] 2 is an exploded perspective view of an internal structure of the lens driving device shown in FIG. 1. [Diagram 3] FIG. 1 is a perspective view of a camera module according to the present invention. [Figure 4]FIG. 4 is an exploded perspective view of the camera module shown in FIG. [Diagram 5] 5 is a perspective view of the lens holder shown in FIG. 4 from a different angle. [Figure 6] FIG. 5 is an exploded perspective view of the support mechanism shown in FIG. [Figure 7] 5 is an exploded perspective view of the support mechanism shown in FIG. 4, seen from a different angle. [Figure 8] 4 is a cross-sectional view showing the internal structure of the camera module shown in FIG. 3. [Figure 9] 4 is a vertical cross-sectional view showing the internal structure of the camera module shown in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The lens driving device and camera module of the present invention will be described below based on the preferred embodiment shown in the accompanying drawings. The drawings referred to below are schematic diagrams prepared for the purpose of explaining the present invention. The dimensions (length, width, thickness, etc.) of each component shown in the drawings do not necessarily reflect the actual dimensions. In addition, the same reference numbers are used for the same or corresponding components in each drawing. In the following description, the Z direction in each drawing may be referred to as the "vertical direction", the positive direction of the Z axis may be referred to as the "upward direction", and the negative direction of the Z axis may be referred to as the "downward direction".

[0014] Hereinafter, the lens driving device and the camera module according to the embodiment of the present invention will be described in detail with reference to Figs. 3 to 9. Fig. 3 is a perspective view of the camera module of the present invention. Fig. 4 is an exploded perspective view of the camera module shown in Fig. 3. Fig. 5 is a perspective view of the lens holder shown in Fig. 4 from another angle. Fig. 6 is an exploded perspective view of the support mechanism shown in Fig. 4. Fig. 7 is an exploded perspective view of the support mechanism shown in Fig. 4 from another angle. Fig. 8 is a horizontal cross-sectional view showing the internal structure of the camera module shown in Fig. 3. Fig. 9 is a vertical cross-sectional view showing the internal structure of the camera module shown in Fig. 3.

[0015] The camera module 100 of the present invention shown in FIG. 3 and FIG. 4 is mounted on a smartphone, an automobile, a drone, a medical device, etc., and is used to capture a stereo image of an arbitrary subject. The camera module 100 includes two optical systems 200 and a lens driving device 1 that holds the two optical systems 200 so as to be drivable along the optical axis direction. The camera module 100 is mounted on a circuit board on which an image sensor is provided, and is used to capture an image of an object. In a state in which the camera module 100 is mounted on the circuit board, two image sensors (not shown) that capture two optical images formed by the two optical systems 200 are provided below the lens driving device 1, and the two optical images formed by the two optical systems 200 are captured to obtain a stereo image of the object. The two optical systems 200 may have the same optical characteristics (for example, focal length, F-number, aberration characteristics, etc.) as each other, or may have different optical characteristics from each other.

[0016] In the illustrated embodiment, each of the two optical systems 200 is depicted as being roughly composed of one lens, but as long as it can collect light from a subject and form an optical image on the imaging surface of the corresponding image sensor, the present invention is not limited to this, and each of the optical systems 200 may be composed of one or more optical elements such as lenses and apertures. In addition, the optical axis direction of the two optical systems 200 coincides with the vertical direction (Z direction) of each figure. Therefore, in the following description, the term "vertical direction" is used to mean the same thing as "optical axis direction of the optical system 200". In addition, the term "upper" is used to mean the same thing as "light receiving side in the optical axis direction of the optical system 200", and further, the term "lower" is used to mean the same thing as "image forming side in the optical axis direction of the optical system 200".

[0017] The two image sensors are mounted on a circuit board on which the camera module 100 is mounted, and have a function of acquiring a stereo image by capturing two optical images formed by the two optical systems 200, respectively. The stereo images acquired by the two image sensors contain parallax according to the positional relationship between the two optical systems 200 and the distance to the subject, and can be used to measure the distance to the subject based on the parallax. The two image sensors are located below the lens driving device 1, and are provided so that the optical axis of the corresponding optical system 200 is substantially perpendicular to the imaging surface of the image sensor, and the optical axis of the corresponding optical system 200 and the center point of the imaging surface of the image sensor are substantially aligned. Any image sensor known in the camera field, such as a color or black-and-white CCD image sensor or a CMOS image sensor, can be used as each of the two image sensors. The stereo images acquired by the two image sensors are transmitted to a control unit (not shown) (for example, a control unit of any device) by wired or wireless communication.

[0018] When the two optical systems 200 are driven synchronously in the optical axis direction by the lens driving device 1, the separation distance between the optical systems 200 and the corresponding image sensors changes, and focus adjustment of the camera module 100 is performed. A control unit is connected to the lens driving device 1, and the lens driving device 1 drives the two optical systems 200 synchronously in response to the current supplied from the control unit to the lens driving device 1. With this configuration, the autofocus function of the camera module 100 is provided.

[0019] As shown in Figure 4, the lens driving device 1 includes a lens holder 2 for holding two optical systems 200, a housing 3 for storing the lens holder 2 internally, a support mechanism 4 for supporting the lens holder 2 within the housing 3 so that it can be driven in the optical axis direction of the optical system 200, and a driving mechanism 5 composed of a coil 51 provided on the lens holder 2 and two magnets 52 provided on the housing 3, for providing a driving force to drive the lens holder 2 in the optical axis direction.

[0020] The lens holder 2 is a cylindrical member made of a non-magnetic material such as a resin material, and has a function of holding two optical systems 200 spaced apart from each other inside. As shown in Figures 4 and 5, the lens holder 2 includes a main body 21 having a rectangular cylindrical shape, two openings 22 formed to penetrate the main body 21 in the optical axis direction (vertical direction) and spaced apart from each other, and a storage section 23 located between the two openings 22 and formed to penetrate the main body 21 in the optical axis direction.

[0021] In the illustrated embodiment, the main body 21 has a square tube shape, but the shape of the main body 21 is not limited as long as the coil 51 can be fixedly provided on the outer circumferential surface of the main body 21. For example, the main body 21 may have a cylindrical shape or a polygonal tube shape. The two openings 22 have a function of holding the two optical systems 200 therein. The two openings 22 have the same configuration and are formed in the main body 21 so as to be spaced apart from each other and arranged in the Y direction. The openings 22 are formed so as to linearly penetrate the main body 21 in the optical axis direction. In the illustrated embodiment, the openings 22 have a cylindrical shape that linearly penetrates the main body 21 in the optical axis direction, but the shape of the openings 22 is not particularly limited as long as the optical system 200 can be held therein. For example, the openings 22 may have a polygonal tube shape or a plurality of grooves for holding each element of the optical system 200, such as a lens or an aperture, are also within the scope of the present invention. The two optical systems 200 can be fixedly held by the lens holder 2 by fixing the optical systems 200 within the opening 22 using any fixing means such as an adhesive, an adhesive tape, a retainer, or the like.

[0022] The storage section 23 has a function of storing the support mechanism 4 therein. The storage section 23 is a through hole formed in the main body section 21 so as to be located between the two openings 22 and to penetrate the main body section 21 in the optical axis direction. The storage section 23 has a substantially rectangular planar shape in a plan view from the Z direction. The storage section 23 includes a first surface 231 on the -Y direction side, a second surface 232 on the +Y direction side, and two receiving grooves 233 formed on the first surface 231. The first surface 231 and the second surface 232 are flat surfaces that are perpendicular to the Y direction and extend in the X direction, and are opposed to each other in parallel while being spaced apart from each other. In addition, a pair of surfaces that extend in the Y direction of the storage section 23 are flat surfaces that are perpendicular to the X direction and are perpendicular to the first surface 231 and the second surface 232.

[0023] The storage section 23 has two receiving grooves 233 formed on the first surface 231. The two receiving grooves 233 are respectively fitted with two first guide members 42 (described later) of the support mechanism 4 (see FIG. 4) therein. The two receiving grooves 233 are formed to extend linearly from the upper end to the lower end of the first surface 231 in the optical axis direction, and extend parallel to each other while being spaced apart from each other. The two receiving grooves 233 have the same configuration, and therefore one receiving groove 233 will be described below as a representative. The receiving groove 233 has a dogleg shape in which the opening width increases linearly from the -Y direction side toward the +Y direction. The two first guide members 42 of the support mechanism 4 are held in the receiving groove 233. In addition, the upper and lower ends of the receiving groove 233 are not closed. Therefore, the upper end of the receiving groove 233 is open toward the top, and the lower end of the receiving groove 233 is open toward the bottom.

[0024] Returning to FIG. 4, the housing 3 is a box-shaped member made of a non-magnetic material such as a resin material, similar to the lens holder 2, and has a function of storing each component of the lens driving device 1 (the lens holder 2, the support mechanism 4, and the driving mechanism 5) therein. The housing 3 includes a rectangular flat upper plate 31, four wall parts 32 extending downward from the upper plate 31, and a rectangular flat base 33 facing the upper plate 31. The upper plate 31 is a rectangular flat part that covers the components stored in the internal space of the housing 3 from above. The upper plate 31 has two circular openings 311 for exposing the two optical systems 200 held by the lens holder 2 to the outside, respectively. Each of the two openings 311 is formed in the upper plate 31 at a position such that the radial center of the opening 311 coincides with the optical axis of the corresponding optical system 200. Light from a subject enters the two optical systems 200 through the two apertures 311, and two optical images of the subject are formed by the two optical systems 200, respectively.

[0025] The four walls 32 are flat portions extending linearly downward from the four edges of the upper plate 31. The upper plate 31 and the upper ends of the four walls 32 are integrally formed. The lower surface of the upper plate 31, the inner surfaces of the four walls 32, and the upper surface of the base 33 define an internal space of the housing 3, and each component of the lens driving device 1 is housed in the internal space. The base 33 is a rectangular flat portion having a shape corresponding to the upper plate 31. Furthermore, the lower ends of the four walls 32 are fixed onto the base 33 by any fixing means such as an adhesive. The base 33 has two circular openings 331 at positions facing the two openings 311 of the upper plate 31, respectively. The light collected by the two optical systems 200 passes through the two openings 331, respectively, and forms an image on the imaging surfaces of the two image sensors located below the base 33.

[0026] The support mechanism 4 has a function of supporting the lens holder 2 in the storage section 23 of the lens holder 2 so as to be drivable in the optical axis direction of the optical system 200. As shown in Fig. 6 and Fig. 7, the support mechanism 4 includes a plate-shaped portion 41 extending in the optical axis direction in the storage section 23, four first guide members 42 located on a first surface 412 on the -Y direction side of the plate-shaped portion 41, two second guide members 43 located on a second surface 413 on the +Y direction side of the plate-shaped portion 41, and an elastic member 44 fixed on the second surface 232 of the storage section 23 of the lens holder 2 and biasing the two second guide members 43 onto the second surface 413 of the plate-shaped portion 41.

[0027] The plate-shaped part 41 is a flat member made of a non-magnetic material such as a resin material, similar to the lens holder 2 and the housing 3. The plate-shaped part 41 extends linearly from the top of the base 33 of the housing 3 upward (to the light receiving side in the optical axis direction). The plate-shaped part 41 includes a flat body part 411, a first surface 412 on the -Y direction side, a second surface 413 on the +Y direction side, a first receiving groove 414 and a second receiving groove 415 formed on the first surface 412, and a third receiving groove 416 formed on the second surface 413. The body part 411 is a plate-shaped part extending on the XZ plane. In addition, each of the side surfaces in the X direction of the body part 411 is a flat surface perpendicular to the X direction, and each of the upper surface and the lower surface of the body part 411 is a flat surface perpendicular to the Z direction. The lower surface of the main body 411 may be integrated with the upper surface of the base 33, or may be fixed onto the upper surface of the base 33 by any fixing means such as an adhesive. In addition, the upper surface of the main body 411 faces the upper plate 31 of the housing 3 with a gap therebetween.

[0028] The first receiving groove 414 has a function of storing two of the four first guide members 42 therein. The first receiving groove 414 is a recess extending linearly from the upper end to the lower end of the first surface 412. The first receiving groove 414 has a dogleg shape with an opening width that increases linearly from the +Y direction to the -Y direction. As shown in FIG. 8, the first guide member 42 is sandwiched between one receiving groove 233 of the lens holder 2 and the first receiving groove 414 of the plate-shaped portion 41.

[0029] Returning to FIG. 6, the second receiving groove 415 has a function of storing the remaining two of the four first guide members 42 inside. The second receiving groove 415 is a rectangular recess extending linearly in the optical axis direction. The upper and lower ends of the second receiving groove 415 are open to the outside. Both side surfaces on the X-direction side forming the second receiving groove 415 are flat surfaces perpendicular to the X-direction, and the opening width of the second receiving groove 415 is constant along the Z-direction. As shown in FIG. 8, the first guide member 42 is sandwiched between the other receiving groove 233 of the lens holder 2 and the second receiving groove 415 of the plate-shaped part 41.

[0030] Returning to FIG. 7, the third receiving groove 416 has a function of storing two second guide members 43 therein. The third receiving groove 416 is a rectangular recess extending linearly in the optical axis direction. The upper and lower ends of the third receiving groove 416 are open to the outside. Both side surfaces on the X-direction side forming the third receiving groove 416 are flat surfaces perpendicular to the X-direction, and the opening width of the third receiving groove 416 is constant along the Z-direction. As shown in FIG. 8 and FIG. 9, the second guide member 43 is sandwiched between the elastic member 44 and the third receiving groove 416 of the plate-shaped portion 41.

[0031] 8, the third receiving groove 416 extends linearly in the optical axis direction at approximately the center in the X direction of the second surface 413. On the other hand, in a plan view from the Z direction, the first receiving groove 414 is located on the -X direction side of the third receiving groove 416, and the second receiving groove 415 is located on the +X direction side of the third receiving groove 416. In addition, in a plan view from the Z direction, it is preferable that the distance from the center of the third receiving groove 416 (the center point of the bottom surface of the rectangular recess) to the center of the first receiving groove 414 (the apex of the dogleg shape) is approximately equal to the distance from the center of the third receiving groove 416 to the center of the second receiving groove 415 (the center point of the bottom surface of the rectangular recess). That is, in plan view from the Z direction, it is preferable that a triangle formed by connecting the center of the first receiving groove 414, the center of the second receiving groove 415, and the center of the third receiving groove 416 with straight lines is an isosceles triangle. With this configuration, it is possible to stabilize the drive of the lens holder 2 along the plate-like portion 41 in the optical axis direction.

[0032] Returning to FIG. 6 and FIG. 7, the four first guide members 42 and the two second guide members 43 have a function of reducing frictional resistance when the lens holder 2 is driven in the optical axis direction. The four first guide members 42 and the two second guide members 43 are formed of any hard material such as a metal material, a ceramic material, or a resin material. In the illustrated embodiment, the four first guide members 42 and the two second guide members 43 are guide balls having a spherical shape, but as long as the frictional resistance when the lens holder 2 is driven in the optical axis direction can be reduced, the present invention is not limited to this, and a cylindrical member extending in the optical axis direction can be used as the first guide members 42 and the second guide members 43. In addition, the number of the first guide members 42 and the second guide members 43 used is not limited to the illustrated embodiment, and the number of the first guide members 42 and the second guide members 43 used may be appropriately changed as necessary.

[0033] Two of the four first guide members 42 are held in a state of being arranged in the Z direction between the first receiving groove 414 of the plate-shaped portion 41 and the receiving groove 233 of the lens holder 2. The remaining two of the four first guide members 42 are held in a state of being arranged in the Z direction between the second receiving groove 415 of the plate-shaped portion 41 and the receiving groove 233 of the lens holder 2. The two second guide members 43 are held in a state of being arranged in the Z direction between the third receiving groove 416 of the plate-shaped portion 41 and the elastic member 44. Therefore, the lens holder 2 is supported by the plate-shaped portion 41 so as to be drivable in the optical axis direction via the four first guide members 42, the two second guide members 43, and the elastic member 44. The plate-shaped portion 41 is provided on the base 33 of the housing 3, which is a fixed member, and the elastic member 44 is fixed on the second surface 232 of the storage portion 23 of the lens holder 2, which is a movable member. In this way, by connecting the fixed member and the movable member with the first guide member 42 and the second guide member 43, it is possible to reduce the frictional resistance force when the lens holder 2 is driven in the optical axis direction.

[0034] The elastic member 44 is fixed on the second surface 232 of the storage section 23 and has a function of biasing the two second guide members 43 into the third receiving groove 416 of the plate-shaped portion 41. In the illustrated embodiment, the elastic member 44 is a leaf spring obtained by performing bending processing on one metal plate, but is not limited to this as long as it is fixed on the second surface 232 and can bias the two second guide members 43 into the third receiving groove 416 of the plate-shaped portion 41. For example, the elastic member 44 may be a coil spring that is fixed on the second surface 232 and biases the two second guide members 43 into the third receiving groove 416 of the plate-shaped portion 41. Hereinafter, a description will be provided assuming that the elastic member 44 is a leaf spring as illustrated.

[0035] The elastic member 44 comprises two base portions 441 fixed on the second surface 232 of the storage section 23, a spring portion 442 protruding from the base portions 441 toward the second surface 413 of the plate-shaped portion 41, and a receiving groove 443 formed in the spring portion 442 so as to extend in the optical axis direction.

[0036] Each of the two base portions 441 is a plate-like portion that is long in the optical axis direction (vertical direction), and is fixed on the second surface 232 of the storage portion 23 by any fixing means such as an adhesive. The length of each of the two base portions 441 in the optical axis direction is approximately equal to the length of the second surface 232 of the storage portion 23 in the optical axis direction. The spring portion 442 is a portion that protrudes from the two base portions 441 toward the second surface 413 of the plate-like portion 41, and provides the springiness of the elastic member 44. The receiving groove 443 is a recess that is long in the optical axis direction and is formed at the top portion (the portion that protrudes most in the -Y direction) of the spring portion 442 so as to be recessed toward the +Y direction.

[0037] The receiving groove 443 has a dogleg shape whose opening width increases linearly from the +Y direction side toward the -Y direction, and is formed at a position facing the third receiving groove 416 of the plate-shaped portion 41. Two second guide members 43 are housed in the receiving groove 443, and as shown by the dotted arrows in Figs. 8 and 9, the spring portion 442 urges the two second guide members 43 housed in the receiving groove 443 into the third receiving groove 416 of the plate-shaped portion 41. In this way, by urging the two second guide members 43 into the third receiving groove 416 of the plate-shaped portion 41 by the elastic member 44, the degree of contact between the lens holder 2 and the support mechanism 4 in the housing portion 23 of the lens holder 2 can be improved, and thus the drive of the lens holder 2 in the optical axis direction can be stabilized. Also, as shown in Fig. 8, the elastic member 44 is separated from the second surface 413 of the plate-shaped portion 41 via a gap and does not contact the second surface 413. Therefore, when the lens holder 2 is driven in the optical axis direction by the driving force provided by the driving mechanism 5, the elastic member 44 can also move in the optical axis direction together with the lens holder 2. In the illustrated embodiment, the receiving groove 443 has a dogleg shape in which the opening width increases linearly from the +Y direction to the -Y direction, but the shape of the receiving groove 443 is not limited to this as long as the two second guide members 43 can be stably stored therein. For example, the receiving groove 443 may have a semi-cylindrical shape corresponding to the shape of the second guide members 43, a rectangular shape similar to the third receiving groove 416 of the plate-like portion 41, or the like.

[0038] Returning to FIG. 4, the driving mechanism 5 has a function of providing a driving force (Lorentz force) that drives the lens holder 2 in the optical axis direction (up and down direction). The driving mechanism 5 includes a coil 51 provided on the outer circumferential surface of the main body 21 of the lens holder 2, and two magnets 52 provided on the inner surfaces of a pair of opposing wall portions 32 of the housing 3. The coil 51 is obtained by winding an electric wire on the outer circumferential surface of the lens holder 2. The coil 51 is fixed on the outer circumferential surface of the main body 21 of the lens holder 2, and drives together with the lens holder 2 in the optical axis direction when the lens holder 2 drives in the optical axis direction. Both ends of the coil 51 are connected to corresponding terminals of the control unit, respectively, and a driving force that drives the lens holder 2 is generated according to the direction and magnitude of the current supplied from the control unit to the coil 51.

[0039] Each of the two magnets 52 is a plate-shaped permanent magnet, and is provided on the inner surfaces of a pair of opposing wall portions 32 of the housing 3 so that the same poles of the two magnets 52 face each other (for example, the N pole of one magnet 52 faces the N pole of the other magnet 52, or the S pole of one magnet 52 faces the S pole of the other magnet 52). Also, each of the two magnets 52 is fixed to the inner surfaces of the pair of opposing wall portions 32 of the housing 3 by any fixing means such as an adhesive.

[0040] Next, the layout of the internal structure of the camera module 100 will be described in detail with reference to Fig. 8 and Fig. 9. Fig. 8 is a horizontal cross-sectional view of the camera module 100 on the XY plane passing through the center of one of the upper first guide members 42 and second guide members 43, two of which are lined up in the optical axis direction. Fig. 9 is a vertical cross-sectional view of the camera module 100 on the YZ plane passing through the center of the second guide members 43, two of which are lined up in the optical axis direction in the third receiving groove 416 of the plate-shaped part 41.

[0041] 8, two magnets 52 are provided on the inner surfaces of a pair of opposing wall portions 32 (a pair of wall portions 32 extending in the Y direction) of the housing 3. Furthermore, the lens holder 2, the support mechanism 4 (the plate-shaped portion 41, the four first guide members 42, the two second guide members 43, and the elastic member 44), the coil 51, and the two optical systems 200 are located between the two opposing magnets 52. Furthermore, the lens holder 2, the support mechanism 4, and the two optical systems 200 are located inside the coil 51.

[0042] With regard to the above-described case where the constituent material of the housing 3 is a non-magnetic material, the constituent material of the housing 3 is not limited to the non-magnetic material, and the housing 3 may be made of a magnetic material. In particular, by using at least a pair of opposing wall portions 32 (a pair of wall portions 32 extending in the Y direction) of the housing 3 on which the two magnets 52 are respectively provided as a magnetic material, the wall portions 32 can function as a yoke and, together with the magnets 52 and the coil 51, can function as a magnetic circuit of the drive mechanism 5.

[0043] With respect to the two first guide members 42 located on the upper side (-X direction side) in Fig. 8, the contact between the first receiving groove 414 of the plate-shaped portion 41 and the first guide members 42 is two-point contact. Similarly, the contact between the receiving groove 233 of the lens holder 2 and the first guide members 42 is two-point contact. Therefore, the connection between the lens holder 2 and the plate-shaped portion 41 via the two first guide members 42 located on the upper side in Fig. 8 is strong, and the two first guide members 42 located on the upper side in Fig. 8 function as the main shaft for driving the lens holder 2.

[0044] On the other hand, the second receiving groove 415 of the plate-shaped portion 41 has a rectangular shape in order to absorb the tolerances of the lens holder 2, the plate-shaped portion 41, the first guide member 42, the second guide member 43, and the elastic member 44. With this configuration, the two first guide members 42 located on the lower side (+X direction side) in FIG. 8 are held by three-point contact between the second receiving groove 415 of the plate-shaped portion 41 and the receiving groove 233 of the lens holder 2. Therefore, the two first guide members 42 located on the lower side in FIG. 8 function as secondary shafts for driving the lens holder 2.

[0045] Moreover, the third receiving groove 416 of the plate-shaped portion 41 has a rectangular shape. With this configuration, the two second guide members 43 are held by three-point contact between the third receiving groove 416 of the plate-shaped portion 41 and the receiving groove 443 of the elastic member 44. With this configuration, the tolerances of the lens holder 2, the plate-shaped portion 41, the first guide member 42, the second guide member 43, and the elastic member 44 can be absorbed, and the degree of adhesion between the lens holder 2 and the support mechanism 4 in the storage portion 23 of the lens holder 2 can be improved. Note that the stationary position of the lens holder 2 in the housing 3 in a stationary state in which no current is supplied to the coil 51 is determined by the pressing force applied to the two second guide members 43 by the elastic member 44. In one example, in the stationary state, the lens holder 2 is located on the upper plate 31 or the base 33 of the housing 3 depending on the direction of gravity. In another example, in the steady state, the lens holder 2 remains at a predetermined steady position spaced apart from the top plate 31 and the base 33 of the housing 3 .

[0046] 8 and 9, the support mechanism 4 is located between the two openings 22 of the lens holder 2, and is housed in a storage section 23 that penetrates the main body 21 of the lens holder 2 in the optical axis direction. When a support mechanism that holds the lens holder 2 vibratably in the optical axis direction with a pair of leaf springs is employed, as in the conventional technology described in the Background Art section, it is necessary to place the pair of leaf springs above and below the lens holder 2. On the other hand, in the present invention, since the support mechanism 4 is housed in the storage section 23 of the lens holder 2, the space in the housing 3 can be used efficiently, and the lens driving device 1 can be made smaller in size.

[0047] Furthermore, in the present invention, the lens holder 2 has two openings 22 for holding the two optical systems 200, respectively, so that one lens holder 2 can hold two optical systems 200. Therefore, compared to the conventional technology described in the Background section, in which two lens holders are used to hold two optical systems, the number of lens holders used can be reduced.

[0048] Furthermore, in the present invention, the lens holder 2 is held so as to be drivable in the optical axis direction by connecting the plate-shaped portion 41 and the lens holder 2 via the first guide member 42 and the second guide member 43, so that unlike the conventional technology described in the Background of the Invention, it is not necessary to use a pair of leaf springs. Also, in the present invention, the two magnets 52 are fixed inside the housing 3 by any fixing means such as an adhesive, so that unlike the conventional technology described in the Background of the Invention, it is not necessary to use a magnet holder. Therefore, according to the present invention, it is possible to reduce the number of parts of the lens driving device 1 compared to the conventional technology described in the Background of the Invention.

[0049] Furthermore, in the present invention, the two optical systems 200 can be driven in the optical axis direction by the driving mechanism 5 composed of one coil 51 and two magnets 52. That is, in the present invention, one coil 51 and two magnets 52 are shared to drive the two optical systems 200 in the optical axis direction. On the other hand, in the conventional technology described in the background art, one coil and two magnets are used for each of the two optical systems, and two coils and four magnets are used in total. Therefore, in the present invention, the number of coils and magnets used can be reduced compared to the conventional technology described in the background art. In this way, according to the present invention, it is possible to provide a lens driving device 1 having a simple configuration with fewer parts and capable of being miniaturized, and a camera module 100 including the lens driving device 1.

[0050] Furthermore, in the present invention, the elastic member 44 biases the two second guide members 43 into the third receiving grooves 416 of the plate-shaped portion 41, thereby improving the degree of contact between the lens holder 2 and the support mechanism 4 in the storage portion 23 of the lens holder 2. As a result, the connection between the plate-shaped portion 41 (i.e., the fixed member) and the lens holder 2 (i.e., the movable member) via the first guide member 42 and the second guide member 43 can be made strong and stable, and the lens holder 2 can be efficiently driven in the optical axis direction.

[0051] Although the lens driving device and the camera module according to each embodiment of the present invention have been described above based on the illustrated embodiment, the present invention is not limited thereto. Each configuration of the embodiment of the present invention can be replaced with any other configuration that can achieve the same function, or any other configuration can be added to each configuration of the embodiment of the present invention.

[0052] A person skilled in the art in the field and technology to which the present invention pertains will be able to modify the configurations of the described lens driving device and camera module of the present invention without significantly departing from the principles, concepts, and scope of the present invention, and lens driving devices and camera modules having modified configurations are also within the scope of the present invention.

[0053] 3 to 9 are merely examples for the purpose of explanation, and the present invention is not necessarily limited thereto. Within the scope of the principles and intent of the present invention, any embodiment in which any component is added or combined, or any component is deleted, is also within the scope of the present invention. [Explanation of symbols]

[0054] REFERENCE SIGNS LIST 1...lens driving device 2...lens holder 21...main body 22...opening 23...storage section 231...first surface 232...second surface 233...receiving groove 3...housing 31...upper plate 311...opening 32...wall 33...base 331...opening 4...support mechanism 41...plate-shaped portion 411...main body 412...first surface 413...second surface 414...first receiving groove 415...second receiving groove 416...third receiving groove 42...first guide member 43...second guide member 44...elastic member 441...base portion 442...spring portion 443...receiving groove 5...driving mechanism 51...coil 52...magnet 100...camera module 200...optical system 500...lens driving device 510...housing 520: Internal structure; 521: Lens holder; 522: Coil; 523: Magnet holder; 524: Magnet; 525: Leaf spring

Claims

1. a lens holder for holding the two optical systems; a housing for accommodating the lens holder therein; a support mechanism for supporting the lens holder in the housing so as to be drivable in the optical axis directions of the two optical systems; a driving mechanism including a coil provided on the lens holder and a magnet provided on the housing, the driving mechanism providing a driving force for driving the lens holder in the optical axis direction; The lens holder includes: A main body portion, two openings that penetrate the main body in the optical axis direction and are spaced apart from each other, and that house the two optical systems therein, respectively; A lens driving device characterized by comprising: a storage section located between the two openings, formed to penetrate the main body in the optical axis direction, and for storing the support mechanism therein.

2. The support mechanism includes: a plate-shaped portion extending in the optical axis direction within the storage portion; The lens driving device according to claim 1 , further comprising: a first guide member positioned between the first surface of the plate-shaped portion and the first surface of the storage portion, the first guide member holding the lens holder so that the lens holder can be driven in the optical axis direction.

3. the housing includes an upper plate having a rectangular flat shape, four wall portions each extending linearly from an edge of the upper plate toward an image forming side in the optical axis direction, and a base facing the upper plate, The lens driving device according to claim 2 , wherein the plate-like portion extends linearly from the base of the housing to a light receiving side in the optical axis direction.

4. The housing portion includes a receiving groove formed on the first surface so as to extend in the optical axis direction, the plate-shaped portion includes a receiving groove formed on the first surface so as to extend in the optical axis direction, The lens driving device according to claim 2 , wherein the first guide member is sandwiched between the receiving groove of the storage portion and the receiving groove of the plate-shaped portion.

5. The support mechanism includes: a second guide member located on a second surface of the plate-shaped portion; The lens driving device according to claim 2 , further comprising an elastic member provided between the second surface of the storage portion and the second surface of the plate-shaped portion, for urging the second guide member onto the second surface of the plate-shaped portion.

6. the plate-shaped portion includes a receiving groove formed on the second surface so as to extend in the optical axis direction, 6. The lens driving device according to claim 5, wherein the second guide member is held in the receiving groove formed on the second surface of the plate-like portion by the elastic member.

7. The elastic member is a plate-shaped base portion fixed on the second surface of the storage portion; a spring portion protruding from the base portion toward the second surface of the plate-shaped portion; A receiving groove is formed in the spring portion so as to extend in the optical axis direction, 7. The lens driving device according to claim 6, wherein the second guide member is sandwiched between the receiving groove formed on the second surface of the plate-like portion and the receiving groove of the elastic member.

8. The lens driving device according to claim 1 , and two optical systems held by the lens holder of the lens driving device.

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