JP2013254164A - Lens drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens drive device that enables compactness in size of the device and efficiently perform an optical axis adjustment.SOLUTION: In a lens drive device 100 to be used while attached to an imaging unit, a plurality of deformable protrusion parts 2a is provided at a bottom of a base 2. Thus, the protrusion part 2a is forced to be deformed by a pressing force and the like to adjust a height of the protrusion part 2a, and an attachment posture of the lens drive device 100 is adjusted, so that it becomes possible to adjust an optical axis of the lens drive device 100. By deforming the protrusion part 2a with the pressing force and the like, the height of the protrusion part 2a is varied to adjust the optical axis thereof. Thus, since a special structure for an optical axis adjustment is not required, the compactness in size of the lens drive device becomes viable and what's more, since there is no work taking much time such as an adhesion work and the like, the efficient optical axis adjustment can be performed.

Description

  The present invention relates to a lens driving device, and more particularly to a lens driving device in which optical axis adjustment is easy.

  In a lens driving device used in an imaging device such as various cameras, a lens unit in which a plurality of lenses are fixed to a lens frame is held by a lens holder that can move in the optical axis direction of the lens unit.

  The lens holder has to be attached to the image pickup apparatus so that the optical axis of the lens unit is not inclined with respect to the reference optical axis of the image pickup apparatus. If the mounting posture is not accurately adjusted, and the optical axis of the lens unit is tilted with respect to the reference optical axis, the image formed by the lens unit is tilted, and a one-blurred image is formed on the element surface of the image sensor. As a result, the imaging performance deteriorates. The reference optical axis of the imaging device is an axis that passes through the center of the imaging device and is orthogonal to the imaging device.

  In recent years, digital imaging devices incorporated in digital cameras or personal digital assistants have become highly accurate in parallel with miniaturization, and lens driving devices incorporated in these imaging devices are also required to be miniaturized. Therefore, it is an important technical problem to improve the imaging performance.

  In response to the above-described demand for higher accuracy in imaging performance, various optical axis adjustment methods have been proposed that adjust the mounting orientation of the lens holder holding the lens unit to increase the optical axis accuracy of the imaging apparatus.

  For example, in the camera module assembly method described in Patent Document 1, as shown in FIG. 7, a lens barrel 913 that holds an optical lens 912, and an optical system holder 914 that holds the lens barrel 913 in a slidable manner. The optical axis adjustment method of the imaging device 910 which consists of the optical block 911 which consists of, and the imaging block 916 which has the imaging device holder 917 and the solid-state imaging device 918 is shown.

  In the conventional optical axis adjustment method described in Patent Document 1, the positions of the lens barrel 913 and the optical system holder 914 and the postures of the optical block 911 and the imaging block 916 are adjusted using a measurement chart (not shown). The optical axis of the optical lens 912 is adjusted to coincide with the reference optical axis, and the lens barrel 913 and the optical system holder 914, and the optical block 911 and the imaging block 916 are fixed with a resin RS such as an ultraviolet curable resin. This method adjusts the optical axis of the image pickup device 910 and increases the optical axis accuracy of the optical block 911.

JP-A-2005-198103

  However, in the conventional optical axis adjustment method as described above, it is unavoidable to touch the adjusted adjustment member when the adjustment member is fixed by adhesion. There was a problem that the adjustment accuracy was lowered.

  In addition, since the adjusted adjusting member is fixed by bonding, an area where an amount of adhesive capable of firmly holding the adjusting component can be applied is required. In addition, in order to securely hold the adjustment parts firmly, it is necessary to apply an amount of adhesive that is more than the amount necessary for holding the adjustment mechanism. A space that does not cause a problem even when the agent flows out of the application place is also required.

  As described above, in the method of fixing the adjustment member by bonding, an area where the required amount of adhesive can be applied is required, and a space that does not cause a problem even when excessively applied adhesive flows out is required. There was a problem that it was difficult to downsize the apparatus.

  Moreover, when fixing with an adhesive agent, it is necessary to hold | maintain the adjusted adjustment member to an adjustment apparatus until an adhesive agent hardens | cured, and there existed a subject that work efficiency was bad.

  On the other hand, a method of achieving the optical axis accuracy only by improving the accuracy of each component of the image pickup apparatus and assembling without adjustment is conceivable. However, in this method, the optical axis required in recent high accuracy is considered. The accuracy cannot be satisfied.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide a lens driving device that can be reduced in size and can efficiently adjust an optical axis.

  In order to solve this problem, a lens driving device according to claim 1 is a lens driving device used by being attached to an imaging unit having an imaging device, and a lens holder to which the lens unit can be attached; A lens driving device comprising: a moving mechanism that holds the lens holder and moves the lens holder in a direction away from or close to the imaging device; and a base that holds the moving mechanism. A feature is that a plurality of spaced apart projections projecting in a direction approaching the imaging unit are provided on the bottom surface of the base that is an attachment side when being attached to the imaging unit, and the plurality of projections are deformable. Have.

  In order to solve this problem, the lens driving device according to claim 2 is characterized in that at least one of the plurality of protrusions is deformed and the height is adjusted.

  In order to solve this problem, the lens driving device according to claim 3 is characterized in that the deformation is performed by either mechanical pressing or heating, or both pressing and heating. Have.

  In order to solve this problem, the lens driving device according to claim 4 is characterized in that the number of the projecting portions is three.

  In order to solve this problem, the lens driving device according to claim 5 is characterized in that the tip of the protrusion is spherical.

  According to the first aspect of the present invention, a plurality of deformable protrusions are provided on the bottom surface of the base of the lens driving device, and the lens driving device is attached to the imaging unit via the plurality of deformable protrusions. To do. As a result, when the lens driving device equipped with the lens unit is attached to the imaging unit, the reference optical axis of the imaging unit passing through the center of the imaging element and orthogonal to the imaging element and the optical axis of the lens unit are inclined. By simply deforming the deformable protrusion, the mounting posture of the lens driving device to the imaging unit can be tilted, and the tilt of the optical axis of the lens unit when mounted on the imaging unit can be corrected. It is possible to efficiently perform the optical axis adjustment work.

  Further, according to the present invention, only by deforming a plurality of deformable protrusions provided on the bottom surface of the base, the mounting posture of the lens unit when the lens driving device is attached to the imaging unit is adjusted, and the light of the lens unit is adjusted. Since the inclination of the axis is corrected, there is no need to provide a place where the adhesive is applied or a space where no trouble occurs even if the adhesive flows out, as in the case where the adjustment part is fixed with an adhesive after adjusting the optical axis. The lens driving device can be downsized.

  In the present invention, since the adjustment of the optical axis accuracy of the imaging unit is completed by deforming a plurality of deformable protrusions provided on the bottom surface of the base, the adhesive is cured as in the case of fixing with an adhesive. Since it is not necessary to hold the adjusted adjustment member until it is completed, the optical axis adjustment work can be completed in a short time, and an efficient adjustment work becomes possible.

  According to the invention of claim 2, since the height of the protruding portion is adjusted by deforming the protruding portion, the height can be adjusted in a short time, and there is no generation of dust or the like due to the height adjustment of the protruding portion. Therefore, there is no need for cleaning work after height adjustment. As a result, it is possible to provide a lens driving device capable of more efficient optical axis adjustment work.

  According to the invention of claim 3, since the protrusion can be reliably deformed by pressing, heating, or pressing while heating, more efficient optical axis adjustment work is possible. A lens driving device can be provided.

  According to the invention of claim 4, since there are three protruding portions, the mounting plane when the lens driving device is attached to the imaging unit is determined by the three protruding portions, and the lens driving device can be stably attached to the imaging unit. Therefore, it is possible to provide a lens drive device that is easy to incorporate.

  In addition, since there are three protrusions, it is possible to easily determine the protrusion whose height is adjusted when adjusting the optical axis, and thus it is possible to provide a lens driving device capable of more efficient optical axis adjustment work.

  According to invention of Claim 5, since the front-end | tip of the protrusion part was made into the spherical shape, the top part of a spherical protrusion part contacts, and a contact area becomes small. As a result, when the protrusion is to be deformed, the vicinity of the top of the protrusion is easily deformed, so that the optical axis can be adjusted more easily.

  Further, according to the fifth aspect of the present invention, in the protruding portion having a spherical tip, even when the specific protruding portion is deformed and the mounting posture of the lens driving device is inclined, the contact portion of the protruding portion that is not deformed is attached. Since the spherical shape at the tip of the protruding portion contacts the imaging unit only by slightly deviating from the top of the spherical protruding portion due to the inclination of the posture, the mounting to the imaging unit can be stably performed.

  Accordingly, it is possible to provide a lens driving device that makes it easy to adjust the optical axis and can be stably attached to the imaging unit by making the tip of the protruding portion spherical.

  As described above, according to the present invention, it is possible to provide a lens driving device that can be miniaturized and can efficiently adjust the optical axis.

It is a figure which shows the external shape of embodiment of the lens drive device which concerns on this invention, (a) is a top view, (b) is a front view, (c) is a bottom view. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an external appearance of a lens driving device according to the present embodiment, where (a) is a perspective view of the lens driving device viewed from above, and (b) is a perspective view of the lens driving device viewed from below. It is a disassembled perspective view which shows the structure of the lens drive device which concerns on this embodiment. 1A is a cross-sectional view illustrating a structure of a lens driving device according to the present embodiment, and FIG. 1A is a cross-sectional view taken along line AA of FIG. 1A illustrating a structure in a state where a lens unit is attached and attached to an imaging unit; ) Is a cross-sectional view taken along the line BB in FIG. FIG. 1B is a cross-sectional view taken along the line BB in FIG. 1A illustrating a method for adjusting an optical axis of a lens drive device according to the present embodiment, and FIG. 1A is a cross-sectional view schematically illustrating a tilt measurement result of the lens drive device; (B) is sectional drawing which shows an optical axis adjustment result typically. 6A and 6B are diagrams illustrating a modification of the lens driving device according to the embodiment, in which FIG. 1A is a cross-sectional view taken along the line BB in FIG. 1A, and FIG. ) Is an enlarged view for explaining the adjustment of the protrusion of the present modification. It is sectional drawing which shows the conventional lens drive device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the following lens drive devices are examples, and are not limited thereto.

  1A and 1B are views showing the outer shape of an embodiment of a lens driving device 100 according to the present invention, wherein FIG. 1A is a plan view, FIG. 1B is a front view, and FIG. 1C is a bottom view. 2A and 2B are perspective views illustrating an appearance of the lens driving device 100 according to the present embodiment, in which FIG. 2A is a perspective view of the lens driving device 100 as viewed from above, and FIG. 2B is a perspective view of the lens driving device 100 as viewed from below. FIG.

  As shown in FIGS. 1 and 2, the lens driving device 100 is a device having a substantially rectangular outer shape in which a yoke 1 is placed above the base 2.

  In the lens driving device 100, a lens unit (not shown) is attached to the lens holder 3, and the bottom surface side of the base 2 is attached to an imaging unit (not shown). The lens driving device 100 changes the distance between the lens unit mounted on the lens holder 3 and the bottom surface of the base 2 and adjusts the focus on the image pickup device mounted on the image pickup unit.

  In the lens driving device 100 according to the present embodiment, the lens driving device 100 is provided with three protruding portions 2a spaced apart from each other on the bottom surface side of the base 2 attached to an imaging unit (not shown).

  Next, the configuration of the lens driving device 100 according to the present embodiment will be described with reference to FIG. FIG. 3 is an exploded perspective view showing the configuration of the lens driving device 100 according to the present embodiment.

  In the lens driving device 100 according to the present embodiment, the base 2 is disposed at the bottom, the lower plate spring 5 is held on the upper surface of the base 2, and the lens holder 3 is attached to the upper surface of the lower plate spring 5. A coil 4 is wound around the holder 3.

  The yoke 1 constituting the outer shape is disposed on the upper surface side of the base 2, a spacer 8 is disposed on the inner top surface of the yoke 1, and an upper leaf spring 6 is disposed on the bottom surface side of the spacer 8. Further, the bottom surface side of the upper leaf spring 6 is held by magnets 7 arranged at the four corners inside the yoke 1.

  The base 2 is formed of a synthetic resin in a substantially plate shape, and a substantially circular sensor opening 2f is formed in the center. A lens (not shown) attached to the lens holder 3 through the sensor opening 2f. An image by the unit is formed on an image sensor on an imaging unit (not shown).

  Fixing projections 2b for fixing the lower plate spring 5 are formed at the four corners of the base 2, and the lower plate spring 5 is attached to the base 2 in a state of being positioned by the fixing projection 2b.

  Note that a wall-like outer peripheral bottom surface 2e (see FIG. 2B) protruding from the inside is provided on the bottom surface side of the base 2 so as to go around the outer periphery of the bottom surface, and the outer peripheral bottom surface 2e has three protruding portions. 2a is spaced apart. Each of the protruding portions 2a is formed in a small-diameter columnar shape. When a large pressing force is applied to the protruding tip portion of the protruding portion 2a, the protruding portion 2a has a small diameter and is plastically deformed, and the height is increased.

  In addition, two conductive metal plates are insert-molded in the base 2. The two metal plates are electrically connected at both ends of the coil 4, and a part of the two metal plates protrudes from one surface of the base 2 to form an external terminal 2 c connected to an imaging unit (not shown). Further, a part of the metal plate on one side partially protrudes from the four corners of the base 2 to form a yoke receiving portion 2d that comes into contact with the lower surface side of the yoke 1 described later.

  The lens holder 3 is formed of a synthetic resin or the like, and has a cylindrical portion 3a in which an external thread portion 3e is formed on the inner peripheral surface, and a flange portion 3b that protrudes radially outward from the lower end side of the cylindrical portion 3a. doing. A lens unit (not shown) is mounted inside the cylindrical portion 3a. On the outer peripheral surface of the cylindrical portion 3a, four coil support portions 3c for supporting the coil 4 from the inner side are formed so as to protrude. An octagonal cylindrical coil 4 is formed by winding a conducting wire around a coil support portion 3c provided in the cylindrical portion 3a. In this case, a gap is formed between the coil 4 and the cylindrical portion 3a so that a pole portion 1b of the yoke 1 described later is inserted.

  The lower leaf spring 5 is constituted by a pair of spring pieces 5a formed of phosphor bronze or the like, and the pair of spring pieces 5a is constituted so as to form an opening along the sensor opening 2f of the base 2 at the center. Yes.

  The yoke 1 is formed in a substantially box shape with a lower surface opened by a soft magnetic material, and a central hole 1a is provided in the approximate center of the upper surface portion, and the yoke 1 is projected so as to protrude downward in the central hole portion 1a. Four pole portions 1b are formed which are opposed to the four corners of the outer wall portion with a space therebetween.

The spacer 8 is formed in a substantially rectangular shape by synthetic resin or the like, and has an opening through which the pole portion 1b of the yoke 1 and the lens holder 3 can be inserted at a substantially center. The upper surface side of the spacer 8 contacts the inner top surface of the yoke 1, and the upper plate spring 6 contacts the lower surface side. The upper plate spring 6 is formed of phosphor bronze or the like, and the cylindrical portion 3a of the lens holder 3 is inserted. A central opening 6a.

  The magnet 7 is a magnetic material such as a neodymium magnet, is formed in a trapezoidal shape when viewed from above according to the shape of the corner of the yoke 1, and is magnetized in a direction connecting the trapezoidal top surface portion 7a and the bottom surface portion 7b. .

  The moving mechanism 20 of the lens driving device 100 according to the present embodiment includes an upper plate spring 6 and a lower plate spring 5 that hold the lens holder 3 movably in the optical axis direction, and a coil that moves the lens holder 3 in the optical axis direction. 4, a magnet 7, and a yoke 1.

  Next, the structure of the lens driving device 100 will be described with reference to FIG. FIG. 4 is a cross-sectional view showing the structure of the lens driving device 100 according to the present embodiment. FIG. 4A shows the structure of the lens unit 92 mounted and attached to the imaging unit 94. FIG. A sectional view at position A, (b) is a sectional view at position BB in FIG.

  4A shows a state in which the lens unit 92 is attached to the lens driving device 100 and the lens driving device 100 is attached to the imaging unit 94. The lens unit 92 and the imaging unit 94 are imaginary lines. It is described in. 4B illustrates the measurement mirror 95 used for the tilt measurement of the lens driving device 100, the measurement mirror 95 is used only during the tilt measurement and is removed after the tilt measurement is completed.

  First, the structure of the lens driving device 100 before the lens unit 92 is mounted will be described.

  A lower plate spring 5 is attached to the upper surface of the base 2 to hold the lens holder 3 movably in a direction orthogonal to the bottom surface of the base 2, and the lens holder 3 is attached to the upper surface of the lower plate spring 5. Further, the upper surface of the upper plate spring 6 is in contact with the lower surface of the spacer 8 disposed on the inner top surface of the yoke 1, and the lower surface of the upper plate spring 6 is held by the upper surface of the magnet 7 attached to the yoke 1. The cylindrical portion 3a of the lens holder 3 is inserted into the central opening 6a (see FIG. 3) of the leaf spring 6, and the lower surface side of the upper leaf spring 6 is in contact with the leaf spring holding surface 3d (see FIG. 3) of the lens holder 3. It touches.

  The upper leaf spring 6 urges the lens holder 3 toward the base 2, and the lower leaf spring 5 urges the lens holder 3 toward the yoke 1 against the urging force of the upper leaf spring 6. . Accordingly, the lens holder 3 is driven in the direction orthogonal to the bottom surface of the base 2, that is, in the direction of the lens optical axis AX0 when the lens unit 92 is attached while being urged by the upper plate spring 6 and the lower plate spring 5. Held in the middle of the range.

  Magnets 7 are attached to the four corners of the yoke 1 so that the upper surface 7 a of the magnet 7 faces the inner peripheral corner of the yoke 1, and the bottom 7 b of the magnet 7 is the central hole of the yoke 1. It faces the four pole portions 1b provided so as to protrude downward from the portion 1a. As a result, a gap 7c flows between the bottom surface 7b of the magnet 7 and the pole 1b of the yoke 1 through which the magnetic flux Df flows. Note that the magnetic flux Df indicated by an arrow in FIG. 4A is a conceptual description of the magnetic flux flow and does not indicate the actual shape of the magnetic flux flow.

  A coil 4 is wound around the lens holder 3, and a gap is formed between the coil 4 and the cylindrical portion 3a. The pole portion 1b of the yoke 1 is inserted into the gap between the coil 4 and the cylindrical portion 3a, and the coil 4 is held in the gap portion 7c.

  In the gap portion 7 c, the magnetic flux Df from the magnet 7 flows in a direction connecting the bottom surface portion 7 b of the magnet 7 and the pole portion 1 b, and the coil 4 wound around the lens holder 3 is perpendicular to the magnetic flux Df. An electric current flows in the direction of circling the cylindrical portion 3a (in FIG. 4, the front and back sides of the page). Therefore, when the coil 4 is energized, according to Fleming's left-hand rule, the direction perpendicular to the two directions of the direction of the magnetic flux Df of the magnet 7 flowing through the gap 7c and the direction of the current flowing through the coil 4, that is, the lens to be attached A force in the direction of the lens optical axis AX0 of the unit 92 is generated in the coil 4.

  Since the lens holder 3 is held in the middle of the driving range in the direction of the lens optical axis AX0 while being urged by the upper plate spring 6 and the lower plate spring 5, the direction and magnitude of the current flowing through the coil 4 can be changed. Thus, the direction and magnitude of the force received by the coil 4 can be changed, whereby the lens holder 3 holding the coil 4 can be moved.

  As described above, the lens holder 3 is moved in the direction of the lens optical axis AX0 by the moving mechanism 20 including the upper plate spring 6, the lower plate spring 5, the coil 4, and the like, thereby driving the lens mounted with the lens unit 92. In a state where the apparatus 100 is attached to the imaging unit 94, it is possible to adjust the focus on the imaging surface 93a of the imaging element 93.

  Next, a structure in a state where the lens unit 92 is attached to the lens driving device 100 and the lens driving device 100 is attached to the imaging unit 94 will be described.

  A lens unit 92 having a lens 91 indicated by an imaginary line in FIG. 4A is attached to the inner peripheral portion of the cylindrical portion 3 a of the lens holder 3. 4A, an image pickup device 93 is provided on the upper surface of the image pickup unit 94, and the image pickup surface 93a of the image pickup device 93 is exposed on the upper surface side of the image pickup unit 94. .

  The lens driving device 100 to which the lens unit 92 is attached is placed on the upper surface of the imaging unit 94, and the protruding tip portion of the protruding portion 2 a of the lens driving device 100 contacts the upper surface of the imaging unit 94.

  The adhesive unit ADH is applied to the outer peripheral bottom surface 2e of the base 2 of the lens driving device 100, the protruding tip portion of the projecting portion 2a is brought into contact with the upper surface of the imaging unit 94, and the adhesive agent ADH is cured, thereby the imaging unit 94. Can be fixed to the lens driving device 100. In the fixing operation of the image pickup unit 94 to the lens driving device 100, only the protrusion tip of the protrusion 2a is brought into contact with the upper surface of the image pickup unit 94, and no inclination adjustment or the like is performed.

  The reference optical axis AX1 of the imaging unit 94 that passes through the center of the imaging element 93 and is perpendicular to the imaging surface 93a is the same as the lens optical axis AX0 of the lens 91 and the imaging element 93 when the lens driving device 100 is attached to the imaging unit 94. It is desirable that the reference optical axis AX1 matches the position and the inclination. In particular, when the tilt between the lens optical axis AX0 and the reference optical axis AX1 is deviated, the image formed on the imaging surface 93a is partially blurred and the quality of the image is degraded. Therefore, the lens optical axis AX0 and the reference optical axis AX1 The slopes must match with high accuracy.

  Usually, the lens optical axis AX0 of the lens 91 is adjusted with reference to the mounting outline of the lens unit 92. Accordingly, the lens optical axis AX0 of the lens unit 92 and the center of the inner diameter portion of the cylindrical portion 3a of the lens holder 3, that is, the holder center CL1 (see FIG. 4B) coincide. The imaging surface 93a of the imaging element 93 is flush with the upper surface of the imaging unit 94 to which the lens driving device 100 is attached.

  Therefore, the inclination between the lens optical axis AX0 of the lens 91 and the reference optical axis AX1 of the image sensor 93 is a robust measurement table for the lens driving device 100 to which the lens unit 92 is not mounted, as shown in FIG. This coincides with the deviation in verticality between the holder center CL1 and the upper surface of the measurement table 96 when placed on 96 or the like.

  Next, a method for measuring the inclination of the holder center CL1 of the lens driving device 100 will be described with reference to FIG.

  As described above, the inclination between the lens optical axis AX0 of the lens 91 and the reference optical axis AX1 of the imaging element 93 when the lens driving device 100 to which the lens unit 92 is attached is attached to the imaging unit 94 is the lens driving device. This coincides with the deviation in verticality between the holder center CL1 and the upper surface of the measurement table 96 when 100 is placed on the measurement table 96 or the like. Therefore, by measuring the inclination of the holder center CL1 of the lens driving device 100, the lens optical axis AX0 of the lens 91 and the imaging element 93 when the lens unit 92 is attached to the lens driving device 100 and attached to the imaging unit 94 are measured. The inclination with respect to the reference optical axis AX1 can be measured.

  When measuring the inclination of the holder center CL1 of the lens driving device 100, as shown in FIG. 4B, the inner peripheral portion of the cylindrical portion 3a of the lens holder 3 of the lens driving device 100, that is, the lens unit 92 is attached. A measurement mirror 95 is attached to the part.

  The measuring mirror 95 has a cylindrical mounting portion 95b protruding from the lower surface side of the substantially disk-shaped top plate portion, and the upper surface of the top plate portion is a mirror surface 95a. The mounting portion 95b has an outer diameter that is held without rattling on the inner peripheral portion of the cylindrical portion 3a of the lens holder 3, and the cylindrical outer shape of the mounting portion 95b and the mirror surface 95a are processed to be perpendicular to each other. Yes.

  Since the mounting portion 95b and the mirror surface 95a are perpendicular to each other, the lens driving device 100 on which the measurement mirror 95 is mounted is placed on the measurement table 96, and the parallelism between the measurement table 96 and the mirror surface 95a, that is, the measurement table 96 By measuring the angle with the mirror surface 95a, the perpendicularity between the measurement table 96 and the holder center CL1 of the lens holder 3 can be measured. The parallelism between the measurement table 96 and the mirror surface 95a can be measured using, for example, an autocollimator.

  Although the measurement mirror 95 is attached to the lens holder 3 and the inclination is measured, the inclination of the lens holder 3 is measured by placing a plate-like mirror whose parallel degree is controlled on the upper surface of the lens holder 3 or the like. You may do it.

  Hereinafter, with reference to FIG. 5, the optical axis adjustment in the lens driving device 100 according to the present embodiment will be described. FIG. 5 is a cross-sectional view of the lens driving device 100 according to the present embodiment, illustrating a method for adjusting the optical axis of the lens driving device 100, taken along the line BB in FIG. 1A. Sectional drawing which shows a method typically, (b) is sectional drawing which shows an optical axis adjustment result typically.

  When measuring the tilt of the holder center CL1 of the lens driving device 100, it is measured that the measurement table 96 (see FIG. 4B) and the mirror surface 95a (see FIG. 4B) are not parallel, that is, FIG. 4 is a schematic cross-sectional view of the lens driving device 100 when the measurement table 96 (see FIG. 4B) and the holder center CL1 of the lens holder 3 (see FIG. 4B) are inclined rather than vertical. As shown in FIG.

  When the lens driving device 100 is placed on the measurement table, the protruding tip plane SP formed by the protruding tip portions of the three protruding portions 2a protruding from the bottom surface of the base 2 coincides with the upper surface of the measuring table. Therefore, in the lens driving device 100 in which the measurement table and the holder center CL1 are inclined rather than perpendicular, the protruding tip plane SP and the holder center CL1 are inclined rather than perpendicular.

  When a line segment that intersects the protruding tip plane SP perpendicularly and passes through a point where the holder center CL1 intersects the protruding tip plane SP is defined as a reference center CL0, the protruding tip plane SP and the holder center CL1 are not perpendicular but inclined. In the lens driving device 100, as shown in FIG. 5A, the holder center CL1 and the reference center CL0 of the protruding tip plane SP are not aligned and are inclined.

  In the lens driving device 100 according to the present embodiment, since the three projecting portions 2a that can be deformed are provided on the bottom surface side of the base 2, the holder center CL1 of the lens driving device 100 is inclined from the reference center CL0. The inclination of the holder center CL1 and the reference center CL0 is reduced by deforming one or two protrusions 2a so that the entire lens driving device 100 is inclined in a direction opposite to the inclination direction of the holder center CL1. Things are possible.

  For example, as shown in FIG. 5A, when the holder center CL1 is inclined counterclockwise from the reference center CL0 by the inclination angle θ1, the entire lens driving device 100 is inclined clockwise. Of the three protrusions 2a, one protrusion 2a is deformed, that is, in the sectional view of FIG. 5A, the protrusion 2a on the right side of the cross section is deformed, and the height of the protrusion 2a is lowered. As a result, as shown in FIG. 5B, the height of the protruding portion 2a on the right side of the cross-sectional view of the three protruding portions 2a is reduced, so that the protruding tip portions of the three protruding portions 2a are formed. The protruding tip plane SP is inclined, and the entire lens driving device 100 is inclined clockwise. Accordingly, the holder center CL1 as well as the lens driving device 100 is inclined in the clockwise direction, so that the reference center CL0 and the holder center CL1 can coincide with each other.

  When the protrusion 2a is deformed to reduce the height of the protrusion 2a, the protrusion tip of the protrusion 2a to be deformed is pressed while holding the upper surface of the yoke 1. Since the protrusion 2a is deformable, the protrusion 2a can be easily plastically deformed, and the height of the protrusion 2a can be reduced. In addition, it is desirable to adjust the pressing force which presses the protrusion part 2a which makes height low according to the inclination amount of the holder center CL1.

  Thus, by deforming the deformable protrusion 2a, the reference optical axis AX1 (see FIG. 4A) of the image pickup device 93 (see FIG. 4A) when the lens driving device 100 equipped with the lens unit is attached to the image pickup unit. 4 (a)), the inclination of the lens optical axis AX0 (see FIG. 4 (a)) of the lens unit 92 (see FIG. 4 (a)) can be reduced.

  The tilt measurement method and the optical axis adjustment method described above are examples of the adjustment method that can be applied to the lens driving device according to the present embodiment. In addition to the above, a dedicated adjustment device is provided to adjust the angle. Various modifications are possible.

  As described above, in the lens driving device 100 according to this embodiment, the optical axis is adjusted by deforming the deformable protrusion 2a provided on the bottom surface of the base 2 and adjusting the height of the protrusion 2a. It is not necessary to provide a special structure for adjustment. Accordingly, it is possible to reduce the size of the lens driving device, and it is possible to perform an efficient optical axis adjustment work because there is no time-consuming work such as a bonding work.

  In addition to the above-described deformation, the method for adjusting the height of the protruding portion 2a includes scraping the protruding tip portion of the protruding portion 2a with a processing method such as cutting, or adding a spacer or the like to the protruding tip portion of the protruding portion 2a. A method such as pasting is conceivable. Among these methods, in the method of attaching a spacer or the like, it is necessary to prepare spacers or the like of various thicknesses so as to be able to cope with various height adjustment amounts. There is a problem that the efficiency of the optical axis adjustment operation is deteriorated because the operation of attaching to the protruding tip is required.

  Further, in the method of scraping off the projecting tip portion of the projecting portion 2a, the machining is completed in a short time, but shaving powder is generated with the machining. In the imaging apparatus, if dust such as shavings adheres to the lens or the like, the imaging performance deteriorates. Therefore, a cleaning operation or the like that reliably removes dust is required, and the efficiency of the optical axis adjustment operation is deteriorated.

  In the lens driving device 100 according to the present embodiment, the optical axis is adjusted by changing the height of the projecting portion 2a by deforming the projecting portion 2a with the pressing force. Therefore, the height adjustment amount is adjusted by adjusting the pressing force. The height adjustment work can be completed in a short time. In addition, as in the case of fixing with an adhesive after adjusting the height, there is no need to provide an area for fixing the adhesive or a space that does not cause a problem even if an excessively applied adhesive flows out. Can be miniaturized. Further, there is no generation of dust or the like as in the case of adjusting the height by cutting the protruding portion 2a, so that a cleaning operation or the like is unnecessary.

  As described above, the optical axis is adjusted by changing the height of the projecting portion 2a by deforming the projecting portion 2a with the pressing force, so that the optical axis adjusting operation can be performed more efficiently.

  In the above description, the protrusion 2a is deformed by the pressing force to change the height of the protrusion 2a and adjust the optical axis. However, by heating the protrusion 2a, the protrusion 2a is deformed to deform the protrusion 2a. You may change the height. Alternatively, when the projecting portion 2a is deformed by a pressing force while being heated, the projecting portion 2a is more easily deformed, so that more efficient optical axis adjustment work can be performed.

  Further, in the lens driving device 100 according to the present embodiment, the number of the protruding portions 2a is three, so that the mounting surface of the lens driving device 100 to the imaging unit is configured by the protruding tip portions of the three protruding portions 2a. Since it becomes the protruding tip plane SP, the lens driving device 100 can be stably attached to the imaging unit.

  Moreover, since the number of the protrusions 2a is three, when adjusting the height of the protrusions 2a, the protrusions 2a to be height-adjusted can be easily determined. For example, when there is any protrusion 2a at a position opposite to the tilt direction of the holder center CL1 of the lens holder 3 in plan view, only the height of one protrusion 2a positioned on the opposite side of the tilt direction is high. You can adjust it. Further, when the position on the opposite side of the tilt direction of the lens holder 3 in the plan view is in the middle of the two protrusions 2a, the heights of the two protrusions 2a may be adjusted. In addition, since the number of the protrusions 2a is three, even if the height of one or two protrusions 2a is adjusted, one or two protrusions 2a whose heights are adjusted are included. Since the protruding tip plane SP is constituted by the protruding tip portions of the two protruding portions 2a, when the lens driving device 100 is attached to the imaging unit, the attachment is not unstable.

  As described above, the lens driving device 100 according to the present embodiment is used by being attached to the imaging unit 94 having the imaging element 93, and holds the lens holder 3 to which the lens unit 92 can be attached, and the lens holder 3. And a moving mechanism 20 that moves the lens holder 3 in a direction away from or close to the imaging element 93 and a base 2 that holds the moving mechanism 20, and is attached when the lens driving device 100 is attached to the imaging unit 94. A plurality of deformable projecting portions 2 a that protrude in a direction approaching the imaging unit 94 and are spaced apart from each other are provided on the bottom surface of the base 2 that is on the side.

  Thus, in the lens driving device 100 according to the present embodiment, the optical axis can be adjusted by deforming the deformable protrusion 2a provided on the bottom surface of the base 2 of the lens driving device 100, and thus the size can be reduced. It is possible to provide a lens driving device that can adjust the optical axis efficiently.

  Further, in the lens driving device 100 according to the present embodiment, since the height is adjusted by deforming at least one of the plurality of protrusions 2a, the height can be adjusted in a short time, and a more efficient optical axis. A lens driving device capable of adjusting work can be provided.

  Further, in the lens driving device 100 according to the present embodiment, the protrusion 2a is deformed by either mechanical pressing or heating, or by both pressing and heating, so the height of the protrusion 2a. It is possible to provide a lens driving device that can be adjusted in a short time and can perform a more efficient optical axis adjustment operation.

Further, in the lens driving device 100 according to the present embodiment, since the number of the protrusions 2a is three, the protrusions 2a can be stably attached to the imaging unit and the height is adjusted when adjusting the optical axis. The optical axis adjustment work is efficient, and even if the height of the protruding portion 2a is adjusted, the optical axis adjustment work can be stably attached to the imaging unit, etc. Can be provided.
[Modification]
A modification of the lens driving device according to the present embodiment will be described with reference to FIG. 6A and 6B are diagrams illustrating a modification of the lens driving device according to the embodiment, in which FIG. 6A is a cross-sectional view of the lens driving device 200 according to the modification, and FIG. 6B is an enlarged view of the protruding portion 2g of the modification. (C) is an enlarged view explaining adjustment of the protrusion part 2g of this modification. The same components as those in the embodiment are denoted by the same reference numerals and detailed description thereof is omitted.

  In the lens driving device 200 of this modification, as shown in FIGS. 6A and 6B, the protruding tip of the protruding portion 2g is spherical, so that the top of the spherical protruding portion 2g comes into contact, and the contact area Becomes smaller. As a result, when the protrusion 2g is to be deformed, a large stress is applied to the top of the protrusion 2g and the vicinity of the top is easily deformed, so that the optical axis adjustment work becomes easier.

  In addition, when the specific protrusion 2g is deformed and the mounting posture of the lens driving device 200 is inclined, when the tip of the protruding portion to which the present modification is not applied is a flat surface, it is not deformed with the inclination of the mounting posture. If the lens driving device is attached to the imaging unit with the flat surface at the tip of the protruding part tilted and the mounting posture is inclined, the entire area of the flat surface of the inclined tip flat surface of the protruding part that is not deformed contacts the imaging unit. It is not possible to touch only the part of the plane. For this reason, there is a possibility that the mounting of the imaging unit may become unstable in a lens driving device in which the tip of the protruding portion to which the present modification is not applied is a flat surface.

  On the other hand, in the lens driving device 200 of the present modification, the tip of the protruding portion 2g is spherical, so even when the specific protruding portion 2g is deformed and the mounting posture of the lens driving device 200 is inclined, it is not deformed. The contact portion of the protruding portion 2g is slightly displaced from the top of the spherical protruding portion 2g due to the inclination of the mounting posture, and the tip of the spherical protruding portion contacts the imaging unit. However, it can be stably attached to the imaging unit without rattling.

  As described above, in the lens driving device 200 according to this modification, the protrusion 2g can be easily deformed by making the protrusion tip of the protrusion 2g spherical, so that the optical axis can be adjusted more easily. In addition, it is possible to provide a lens driving device that can be stably attached to the imaging unit, can be stably attached to the imaging unit, and can efficiently adjust the optical axis.

DESCRIPTION OF SYMBOLS 1 Yoke 1a Center hole part 1b Pole part 2 Base 2a Projection part 2b Fixing projection part 2c External terminal 2d Yoke receiving part 2e Outer bottom face 2f Sensor opening part 2g Projection part 3 Lens holder 3a Cylindrical part 3b Flange part 3c Coil holding part 3d Leaf spring holding surface 3e Male thread portion 4 Coil 5 Lower leaf spring 5a Spring piece 6 Upper leaf spring 6a Center opening 7 Magnet 7a Top surface portion 7b Bottom surface portion 7c Gap portion 8 Spacer 20 Moving mechanism 91 Lens 92 Lens unit 93 Image sensor 93a Imaging surface 94 Imaging unit 95 Measuring mirror 95a Mirror surface 95b Mounting part 96 Measurement table 100 Lens driving device 200 Lens driving device ADH Adhesive AX0 Lens optical axis AX1 Reference optical axis CL0 Reference center CL1 Holder center Df Magnetic flux SP Projection tip plane θ1 Angle of inclination

Claims (5)

A lens driving device used by being attached to an imaging unit having an imaging element,
A lens holder on which a lens unit can be mounted; a moving mechanism that holds the lens holder and moves the lens holder in a direction away from or close to the imaging device; and a base that holds the moving mechanism. In the lens driving device provided,
A plurality of spaced apart projections projecting in a direction approaching the imaging unit are provided on the bottom surface of the base on the mounting side when the lens driving device is attached to the imaging unit, and the plurality of projections can be deformed. A lens driving device characterized by that.
The lens driving device according to claim 1, wherein at least one of the plurality of projecting portions is deformed and the height is adjusted.
The lens driving device according to claim 2, wherein the deformation is made by either mechanical pressing or heating, or both pressing and heating.
The lens driving device according to claim 1, wherein the number of the projecting portions is three.
The lens driving device according to claim 1, wherein a tip of the protruding portion is spherical.