JP2013109231A - Lens drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens drive device capable of controlling an attraction force between a moving body and a support body, thereby highly accurately controlling the position of the moving body, even when the moving body is directly moved to a predetermined position from an initial state where the moving body comes into contact with the support body in an optical axis direction.SOLUTION: In a lens drive device 1, during a dormant period when the energization of coils 31 and 32 is stopped to stop a magnetic drive mechanism 5, a moving body 3 is in the initial state where the moving body 3 is located on an image side and the image side end of a sleeve 13 is in contact with a holder 19 with elasticity, by the energizing force of at least one of a rear spring member 14x and a front spring member 14y. At this time, a contact surface where the sleeve 13 comes into contact with the holder 19 and a reference surface where the holder 19 comes into contact with the sleeve 13 have UV irradiation processing etc., to reduce the attraction force between the holder 19 and the sleeve 13.

Description

  The present invention relates to a lens driving device in which a moving body having a lens is connected to a support via a spring member.

  A lens driving device mounted on a mobile phone with a camera, a digital camera, or the like includes a support, a moving body including a lens, and a magnetic driving mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction. The moving body is moved in the optical axis direction by energizing the coil of the magnetic drive mechanism.

  In addition, a spring member connected to the support body and the moving body is provided to urge the moving body to one side in the optical axis direction, and the moving body is lighted against the support body when the magnetic drive mechanism is in a stopped state. The structure which makes it the initial state which contacts in an axial direction is proposed (refer patent document 1).

JP 2011-154121 A

  In the lens driving device having the configuration described in Patent Document 1, for example, a driving method in which a driving current is reduced after a large driving current is supplied to a coil to separate a moving body and a support from each other is often employed. However, in the case of such a driving method, current consumption increases.

  Here, the inventor of the present application directly moves from the initial state where the moving body contacts the support body in the optical axis direction for the purpose of moving the moving body to the predetermined position without causing an increase in current consumption. Therefore, it is possible to improve the responsiveness and reduce the current consumption.

  However, when the level of the drive current supplied to the coil is low, it has been found that the position of the moving body cannot be accurately controlled due to the adsorption of the moving body and the support as described below. That is, when the drive current to the coil of the magnetic drive mechanism is gradually increased from the state where the moving body and the support are in contact with each other in a section where the level of the drive current supplied to the coil is low, the drive current value and the moving body The displacement amount has a relationship indicated by an arrow L11 in FIG. 8, but when the drive current to the coil of the magnetic drive mechanism is gradually reduced from the state where the moving body and the support are separated from each other, the drive current The value and the displacement amount of the moving body have a relationship indicated by an arrow L12 in FIG. Here, as can be seen by comparing the relationship indicated by the arrow L11 and the relationship indicated by the arrow L12, when the driving current to the coil is gradually increased from the state where the moving body and the support are in contact, the moving body and the support are supported. The moving body and the support come into contact with each other when the drive current to the coil is gradually reduced from the state in which the moving body and the support are separated from the movement start current value I11 (mA) when the body is separated. Since there is a large difference ΔI15 with the movement end current value I12 (mA), the moving body moves directly to a predetermined position from the initial state where it contacts the support in the optical axis direction. The knowledge that it was difficult to move the body was acquired.

In view of the above problems, an object of the present invention is to control a suction force between the moving body and the support, thereby directly moving the predetermined position from the initial state in which the moving body contacts the support in the optical axis direction. It is an object of the present invention to provide a lens driving device capable of accurately controlling the position of a moving body even when the moving body is moved.

  In order to solve the above problems, in the present invention, a support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body in the lens optical axis direction with respect to the support, and the moving body. Is biased toward one side in the optical axis direction, and when the magnetic drive mechanism is in a stopped state, the contact surface of the movable body is brought into an initial state in which it contacts the reference surface of the support body in the optical axis direction. And a reference member when the drive current to the coil of the magnetic drive mechanism is gradually increased from a state in which the contact surface and the reference surface are in contact with each other. When the drive current to the coil of the magnetic drive mechanism is gradually decreased from the state in which the movement start current value (mA) when the surface is separated and the contact surface and the reference surface are separated from each other, Movement end current value (mA) when the contact surface comes into contact with the reference surface Relative difference between the value when multiplied by the thrust constant (gf / mA) at the time of driving the movable body by the magnetic drive mechanism is equal to or less than 0.2 gf.

  In the lens driving device to which the present invention is applied, the value obtained by multiplying the difference between the movement start current value (mA) and the movement end current value (mA) by the thrust constant (gf / mA) is managed. The value is set to a small value of 0.2 gf or less. For this reason, since the attraction force between the moving body and the support body can be managed to be small, even when the moving body moves directly to a predetermined position from the initial state where the moving body contacts the support body in the optical axis direction. The position of the moving body can be controlled with high accuracy. For this reason, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

In the present invention, a value obtained by dividing the thrust constant (gf / mA) by the contact area (mm ² ) between the contact surface and the reference surface is 0.02 ((gf / mA) / mm ² ) or more. It is preferable that According to such a configuration, it is possible to efficiently reduce the adsorption force between the moving body and the support body because the overlapping area between the contact surface and the reference surface is narrow as viewed from the thrust constant.

  In the present invention, it is preferable that at least one of the contact surface and the reference surface is a tip surface of a protrusion protruding from one side of the moving body and the support body toward the other side. According to such a configuration, the adsorption force between the moving body and the support body can be efficiently reduced because the overlapping area between the contact surface and the reference surface is narrow.

  In the present invention, it is preferable that at least one of the abutment surface and the reference surface is subjected to a process for reducing an adsorption force between the abutment surface and the reference surface. According to such a configuration, since the adsorption force between the moving body and the support can be reduced, the moving body is moved directly to a predetermined position from the initial state where the moving body contacts the support in the optical axis direction. Even in this case, the position of the moving body can be controlled with high accuracy.

  In the present invention, it is preferable that at least one of the contact surface and the reference surface is subjected to UV irradiation treatment. According to such a configuration, the contact surface or the reference surface can be easily and reliably cleaned in the cleaning process, so that the adsorption force between the moving body and the support can be efficiently reduced.

  The form of adopting such a UV irradiation treatment is that the reference surface and the reference surface are formed between the contact surface and the portion that is shaded when viewed from the contact surface side in the movable body, and the support body. It can be defined as a configuration in which there is a difference in hardness in at least one of the portions that are shaded when viewed from the side.

Further, the form of adopting the UV irradiation treatment is that the moving body is between the contact surface and a portion that is shaded when viewed from the corresponding contact surface side, and the reference surface and the reference surface side of the support body. It can also be defined by a configuration in which there is a difference in absorption peak position in the wave number range when infrared spectroscopic analysis is performed at least one of the locations that are shaded from the viewpoint. For example, the difference between the absorption peak positions appears in the wave number region from 1728 cm ⁻¹ to 1743 cm ⁻¹ .

  In this invention, you may employ | adopt the structure by which the roughening process is performed to at least one of the said contact surface and the said reference surface. According to this configuration, the adsorption force between the moving body and the support can be efficiently reduced.

  According to another aspect of the present invention, there is provided a support body, a movable body including a lens, a magnetic drive mechanism that magnetically drives the movable body with respect to the support body in a lens optical axis direction, and the movable body as a light beam. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state In the lens driving device having the above, the adsorption force between the moving body and the support body is reduced by adopting the following configuration. For this reason, even when moving a mobile body to the predetermined position directly from the initial state which a mobile body contacts with a support body in an optical axis direction, the position of a mobile body can be controlled accurately. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

That is, another embodiment of the present invention includes a support, a moving body provided with a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and the moving body is optically driven. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state And the thrust constant (gf / mA) when the moving body is driven by the magnetic drive mechanism is divided by the overlapping area (mm ² ) of the contact surface and the reference surface. Is 0.02 ((gf / mA) / mm ² ) or more. According to such a configuration, it is possible to efficiently reduce the adsorption force between the moving body and the support body because the overlapping area between the contact surface and the reference surface is narrow as viewed from the thrust constant. For this reason, even when moving a mobile body to the predetermined position directly from the initial state which a mobile body contacts with a support body in an optical axis direction, the position of a mobile body can be controlled accurately. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

  According to another aspect of the present invention, there is provided a support body, a movable body including a lens, a magnetic drive mechanism that magnetically drives the movable body with respect to the support body in a lens optical axis direction, and the movable body as a light beam. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state And at least one of the contact surface and the reference surface is subjected to a process for reducing an adsorption force between the contact surface and the reference surface. To do. According to such a configuration, since the adsorption force between the moving body and the support can be reduced, the moving body is moved directly to a predetermined position from the initial state where the moving body contacts the support in the optical axis direction. Even in this case, the position of the moving body can be controlled with high accuracy. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

According to another aspect of the present invention, there is provided a support body, a movable body including a lens, a magnetic drive mechanism that magnetically drives the movable body with respect to the support body in a lens optical axis direction, and the movable body as a light beam. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state And at least one of the contact surface and the reference surface is subjected to a UV irradiation process. According to such a configuration, the contact surface or the reference surface can be easily and reliably cleaned in the cleaning process, so that the adsorption force between the moving body and the support can be efficiently reduced. For this reason, even when moving a mobile body to the predetermined position directly from the initial state which a mobile body contacts with a support body in an optical axis direction, the position of a mobile body can be controlled accurately. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

  According to another aspect of the present invention, there is provided a support body, a movable body including a lens, a magnetic drive mechanism that magnetically drives the movable body with respect to the support body in a lens optical axis direction, and the movable body as a light beam. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state In the lens driving device, the moving body is between the contact surface and a portion that is shaded when viewed from the contact surface side, and the support body is shaded when viewed from the reference surface and the reference surface side. It is characterized in that there is a difference in hardness in at least one of the locations. The form in which the UV irradiation treatment is adopted is that the moving body is hidden between the contact surface and a portion that is shaded when viewed from the contact surface side, and the support body is shaded when viewed from the reference surface and the reference surface side. It can be defined as a configuration in which there is a difference in hardness in at least one of the locations. Therefore, according to the UV irradiation, the contact surface or the reference surface can be easily and surely cleaned in the cleaning process, so that the adsorption force between the moving body and the support can be efficiently reduced. For this reason, even when moving a mobile body to the predetermined position directly from the initial state which a mobile body contacts with a support body in an optical axis direction, the position of a mobile body can be controlled accurately. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

According to another aspect of the present invention, there is provided a support body, a movable body including a lens, a magnetic drive mechanism that magnetically drives the movable body with respect to the support body in a lens optical axis direction, and the movable body as a light beam. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state In the lens driving device, the moving body is between the contact surface and a portion that is shaded when viewed from the contact surface side, and the support body is shaded when viewed from the reference surface and the reference surface side. There is a difference in the absorption peak position in the wave number range when infrared spectroscopic analysis is performed at least one of the locations. For example, the difference between the absorption peak positions appears in the wave number region from 1728 cm ⁻¹ to 1743 cm ⁻¹ . The form of adopting the UV irradiation treatment is that the moving body is between the contact surface and a portion that is shaded when viewed from the corresponding contact surface side, and the support body is viewed from the reference surface and the reference surface side. It can also be defined by a configuration in which there is a difference in absorption peak position in the wave number region when performing infrared spectroscopic analysis at least one of the shaded portions. Therefore, according to the UV irradiation, the contact surface or the reference surface can be easily and reliably cleaned in the cleaning process, so that the adsorption force between the moving body and the support can be efficiently reduced. For this reason, even when moving a mobile body to the predetermined position directly from the initial state which a mobile body contacts with a support body in an optical axis direction, the position of a mobile body can be controlled accurately. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

According to another aspect of the present invention, there is provided a support body, a movable body including a lens, a magnetic drive mechanism that magnetically drives the movable body with respect to the support body in a lens optical axis direction, and the movable body as a light beam. A spring member that is biased to one side in the axial direction and is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state And a roughening process is performed on at least one of the contact surface and the reference surface. According to this configuration, the adsorption force between the moving body and the support can be efficiently reduced. For this reason, even when moving a mobile body to the predetermined position directly from the initial state which a mobile body contacts with a support body in an optical axis direction, the position of a mobile body can be controlled accurately. Therefore, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

  In the case of adopting such a form, at least one of the contact surface and the reference surface is from a front end surface of a protrusion protruding from one side of the movable body and the support body toward the other side. It is preferable to become.

  In the lens driving device to which the present invention is applied, since the adsorption force between the moving body and the support is reduced, the moving body moves directly to a predetermined position from the initial state where the moving body contacts the support in the optical axis direction. Even in the case of moving, the position of the moving body can be controlled with high accuracy. For this reason, the position of the moving body can be controlled in a section where the level of the drive current supplied to the coil is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism can be reduced.

It is explanatory drawing which shows the whole structure of the lens drive device to which this invention is applied. It is the disassembled perspective view which decomposed | disassembled further finely the lens drive device to which this invention is applied. It is a longitudinal cross-sectional view which shows a mode that the lens drive device to which this invention is applied was cut | disconnected by XZ surface. It is explanatory drawing of the moving body used for the lens drive device to which this invention is applied. It is explanatory drawing which shows the change of the hardness at the time of performing UV irradiation to a sleeve etc. It is explanatory drawing which shows the change of the infrared absorption spectrum at the time of performing UV irradiation to a sleeve etc. It is explanatory drawing of the drive characteristic of the lens drive device to which this invention is applied. It is explanatory drawing which shows the problem of the conventional lens drive device.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following description, the optical axis direction is the Z-axis direction, the direction orthogonal to the Z-axis direction is the X-axis direction, and the direction orthogonal to the X-axis direction and the Z-axis direction is the Y-axis direction. In the drawings referred to below, one side in the X-axis direction is the X1 side, the other side is the X2 side, one side in the Y-axis direction is the Y1 side, the other side is the Y2 side, and one side in the Z-axis direction The side (optical axis direction rear side / image side) is shown as Z1 side, and the other side (optical axis direction front side / subject side) is shown as Z2 side. In addition to the camera-equipped mobile phone, the lens driving device described below can be attached to various electronic devices. For example, it can be used for a thin digital camera, PHS, PDA, bar code reader, surveillance camera, camera for checking the back of a car, a door having an optical authentication function, and the like.

(Entire configuration of lens driving device)
FIG. 1 is an explanatory diagram showing the overall configuration of a lens driving device to which the present invention is applied. FIGS. 1 (a) and 1 (b) respectively show the lens driving device to which the present invention is applied in the optical axis direction front side (subject side). FIG. 2 is an external view seen from the above and an exploded perspective view seen from the front side in the optical axis direction. FIG. 2 is an exploded perspective view in which the lens driving device to which the present invention is applied is further disassembled in detail. FIGS. 2A and 2B are an exploded perspective view seen from the front side in the optical axis direction and a rear side in the optical axis direction. It is the disassembled perspective view seen from. FIG. 3 is a longitudinal sectional view showing a state in which the lens driving device to which the present invention is applied is cut along the XZ plane. In FIG. 1B, FIG. 2 and FIG. 3, the entire lens holder including the lens is omitted.

  1, 2, and 3, the lens driving device 1 according to the present embodiment is a thin camera used for a camera-equipped mobile phone or the like. For example, a lens 36 or an aperture approaches a subject (object) along the optical axis L direction. It is for moving in both directions of the A direction (front side) and the B direction (rear side) approaching the side opposite to the subject (image side), and has a substantially rectangular parallelepiped shape. The lens driving device 1 generally includes a moving body 3 having a cylindrical lens holder 37 having one or a plurality of lenses 36 and a fixed aperture inside, and the moving body 3 in the direction of the optical axis L of the lens 36. It has a magnetic drive mechanism 5 that is moved along, and a support 2 on which the magnetic drive mechanism 5 and the moving body 3 are mounted. The movable body 3 is provided with a cylindrical sleeve 13, and a cylindrical lens holder 37 is fixed inside thereof. The outer shape of the moving body 3 is defined by the sleeve 13 and has a substantially quadrangular prism shape.

  The support 2 has a holder 19 made of a rectangular resin plate for holding an image pickup device (not shown) on the rear side, and a box-shaped yoke 18 on the front side in the optical axis L direction, and A spring supporting spacer 11 is provided. A spacer opening 110 and a yoke opening 180 for taking light from the subject into the lens 36 are formed in the center of the spacer 11 and the yoke front plate 185 of the yoke 18, respectively. In the yoke front plate portion 185 of the yoke 18, the yoke opening 180 includes an arc portion 188 having a large curvature radius and an arc portion 189 having a small curvature radius. In the spacer 11, the spacer opening portion 110 has a large curvature radius. It consists of an arc portion 118 and an arc portion 119 with a small radius of curvature. The yoke 18 is made of a ferromagnetic plate such as a steel plate, and constitutes an interlinkage magnetic field generator that generates an interlinkage magnetic field in the coils 31 and 32 held by the sleeve 13 together with the magnet 17 as will be described later. The spacer 11 is made of nonmagnetic metal or resin.

  The holder 19 is formed with an opening 190 that allows the image sensor to receive light incident on the central portion of the rectangular bottom plate portion 191 through the lens 36. The holder 19 holds terminal members 195 a and 195 c for supplying power to the coils 31 and 32 and 195 b for grounding the yoke 18.

(Configuration of magnetic drive mechanism 5)
The magnetic drive mechanism 5 includes coils 31 and 32 wound around the outer peripheral surface of the sleeve 13, and a linkage magnetic field generator that generates a linkage magnetic field in the coils 31 and 32. A magnetic drive mechanism 5 is configured by the magnetic field generator. The linkage magnetic field generator includes four magnets 17 facing the coils 31 and 32 on the outer peripheral side, and the yoke 18 is also used as a component of the magnetic drive mechanism 5 in this embodiment.

  The yoke 18 has a box shape including a yoke front plate portion 185 that covers the front side of the coil 32 positioned on the front side in the optical axis L direction, and a rectangular tube-shaped body portion 186. The yoke front plate portion 185 includes: Opposite the front end of the moving body 3 in the optical axis L direction. The rectangular tubular body 186 includes side plate portions 181, 182, 183, and 184 that cover the side surfaces of the coils 31 and 32, and leaks from a magnetic path formed between the magnet 17 and the coils 31 and 32. Reduces magnetic flux.

In this embodiment, each of the four magnets 17 has a rectangular plate shape, and is fixed to the inner surfaces of the side plate portions 181, 182, 183, and 184 at the side portions avoiding the four corners of the yoke 18. The four magnets 17 are all divided into two in the direction of the optical axis L, and in any case, the inner surface and the outer surface are magnetized to different poles. In the four magnets 17, for example, the inner surface is magnetized to the N pole in the upper half, the outer surface is magnetized to the S pole, and the inner surface is magnetized to the S pole in the lower half, and the outer surface is magnetized to the N pole. ing. Therefore, the winding direction of the coil wire is opposite between the coil 31 and the coil 32.

(Spacer configuration)
In this embodiment, the spacer 11 is a rectangular frame-shaped component having a spacer opening 110. The spacer 11 is fixed to the yoke 18 by bonding or the like while being overlapped with the inner surface of the yoke front plate portion 185 of the yoke 18, and is interposed between the yoke front plate portion 185 and the movable body 3. The rear surface of the spacer 11 is provided with a protrusion (not shown) protruding rearward from the corner portion, and the protrusion has a function of holding a front spring member 14y described below.

(Configuration of spring member and its surroundings)
The lens driving device 1 according to this embodiment includes a rear spring member 14x and a front spring that connect the support body 2 and the movable body 3 between the holder 19 and the sleeve 13 and between the spacer 11 and the sleeve 13, respectively. A member 14y is provided. Both the rear spring member 14x and the front spring member 14y are made of metal such as copper alloy or SUS steel, and are formed by pressing a thin plate having a predetermined thickness or etching using a photolithography technique. . The rear spring member 14x and the front spring member 14y are in a state where the movable body 3 is supported by the support body 2 so as to be movable along the optical axis L.

  Of the rear spring member 14x and the front spring member 14y, the rear spring member 14x disposed on the holder 19 side (image side) is divided into two spring pieces 14a and 14b. The two ends (the winding start end and the winding end end) are electrically connected to the spring pieces 14a and 14b, respectively. The two spring pieces 14 a and 14 b are electrically connected to terminal members 195 a and 195 c held by the holder 19, respectively. Accordingly, the rear spring member 14 x (spring pieces 14 a and 14 b) also functions as a power supply member for the coils 31 and 32.

(Configuration of magnetic spring)
The lens driving device 1 further includes a ring-shaped magnetic piece 130 held at the upper end of the sleeve 13, and such a magnetic piece 130 is applied to the moving body 3 by an attractive force acting between the magnet 17. On the other hand, a magnetic spring that applies an urging force in the direction of the optical axis L is configured. For this reason, since it is possible to prevent the mobile body 3 from being displaced by its own weight when no current is applied, it is possible to maintain the mobile body 3 in a desired posture and to further improve the impact resistance.

(Configuration of sleeve 13)
On the outer peripheral surface of the sleeve 13, rectangular rib-shaped protrusions 138 and 139 are formed at the image-side end portion and the front-side end portion, and the rib-shaped protrusion 136 is at an intermediate position between the rib-shaped protrusions 138 and 139. Is formed. For this reason, on the outer peripheral surface of the sleeve 13, a portion where the coil 31 is wound around the portion sandwiched between the rib-like projections 136, 138 is formed, and the coil 32 is wound around the portion sandwiched between the rib-like projections 136, 139. A rotating part is formed.

  In the sleeve 13, the upper surface of the rib-shaped protrusion 139 is an annular stepped portion that constitutes a spring connecting portion 13 y for connecting the front spring member 14 y, and the lower end surface (image side end surface) of the sleeve 13 is the rear side. It is a spring connecting portion 13x for connecting the spring member 14x. In addition, the magnetic piece 130 (magnetic spring) is arrange | positioned around the spring connection part 13y.

(Detailed configuration of the front spring member 14y and the rear spring member 14x)
FIG. 4 is an explanatory diagram of the moving body 3 used in the lens driving device 1 to which the present invention is applied. FIGS. 4 (a), (b), (c), (d), and (e) are moving bodies. 3 is a perspective view showing a state in which the rear spring member 14x is mounted on the rear side in the optical axis direction, and a state in which the movable body 3 and the rear side spring member 14x are separated from the rear side in the optical axis direction. A perspective view, a bottom view when the rear spring member 14x is attached to the movable body 3 from the rear side in the optical axis direction, and a state where the rear spring member 14x is attached to the movable body 3 on the other side Y2 in the Y-axis direction. FIG. 6 is a side view when viewed from the side and an explanatory view showing an enlarged contact surface of the movable body 3.

  As shown in FIG. 2, the front spring member 14 y is connected to the spacer 11 on the outer peripheral side of the annular frame-like moving body side connecting portion 144 connected to the front end portion of the sleeve 13 and the moving body side connecting portion 144. Four support body side connection parts 143 and four arm parts 145 that connect the support body side connection parts 143 and the mobile body side connection parts 144 are provided, and the mobile body side connection parts 144 are located inside the support body side connection parts 143. Located on the circumferential side. Each of the four support body side connecting portions 143 is formed with a hole for connection to the spacer 11.

  In this embodiment, the support body side connecting portion 143 is provided at a position overlapping each of the four corner portions of the spacer 11 and the yoke front plate portion 185 described with reference to FIG. 1 and FIG. Thus, they are arranged at equiangular intervals in the circumferential direction. All of the four arm portions 145 extend from the connecting portion with the support side coupling portion 143 in a substantially arc shape and extend to the moving body side coupling portion 144.

  As shown in FIGS. 4A and 4B, the rear spring member 14x is slightly different in size and shape from the front spring member 14y, but the basic structure is the same as that of the front spring member 14y. It is. That is, the rear spring member 14x is substantially the same as the front spring member 14y, and the movable body side coupling portion 144 coupled to the sleeve 13 and the four support body side couplings coupled to the holder 19 on the outer peripheral side of the movable body side coupling portion 144. Part 143, and four arm parts 145 which connect supporter side connecting part 143 and movable body side connecting part 144. Each of the four support body side connecting portions 143 is formed with a hole for connection to the holder 19. The support body side coupling portion 143 is provided at a position overlapping each of the four corner portions of the holder 19 described with reference to FIGS. 1 and 2, and all of the four arm portions 145 are the support body side coupling portion 143. And extending from the connecting portion to the moving body side connecting portion. Here, the rear spring member 14 x is divided into two spring pieces 14 a and 14 b by two discontinuous portions provided in the moving body side connecting portion 144, and is used as a power supply member for the coils 31 and 32. Accordingly, both ends (winding start end and winding end end) of one coil wire constituting the coils 31 and 32 are connected to the two spring pieces 14a and 14b by a method such as soldering. However, the rear spring member 14x is connected to the spring pieces 14a and 14b through a frame-like part (not shown) until the middle of manufacture, and the two spring pieces 14a, 14b.

(Basic operation)
In FIG. 3, in the lens driving device 1 of the present embodiment, the energizing force of the rear spring member 14 x and the front spring member 14 y is applied during a pause period in which the energization of the coils 31 and 32 is stopped to stop the magnetic drive mechanism 5. The moving body 3 is located on the image side, and is in an initial state in which the image side end portion of the sleeve 13 is in contact with the holder 19 with elasticity.

In such an initial state, when a current in a predetermined direction is passed through the coils 31 and 32, the coils 31 and 32 receive an upward (front) electromagnetic force, respectively. Thereby, the sleeve 13 to which the coils 31 and 32 are fixed starts to move to the front side in the optical axis L direction (front side / direction indicated by the arrow A). At this time, elastic forces that restrict the movement of the sleeve 13 are generated between the front spring member 14y and the front end of the sleeve 13 and between the rear spring member 14x and the image end of the sleeve 13, respectively. To do. For this reason, when the electromagnetic force that attempts to move the sleeve 13 to the front side and the elastic force that restricts the movement of the sleeve 13 are balanced, the sleeve 13 stops. At this time, the sleeve 13 (moving body 3) is brought to a desired position by adjusting the amount of current flowing through the coils 31 and 32 according to the elastic force acting on the sleeve 13 by the rear spring member 14x and the front spring member 14y. Can be stopped.

  In this embodiment, since the rear spring member 14x and the front spring member 14y are leaf springs (gimbal springs) in which a linear relationship is established between the elastic force (stress) and the displacement amount (strain amount), the sleeves are used. The linearity between the amount of movement of 13 and the current passed through the coils 31 and 32 can be improved. Further, since two spring members including the rear spring member 14x and the front spring member 14y are used, a large balance force is applied in the direction of the optical axis L when the sleeve 13 is stopped. Even if other force such as centrifugal force or impact force acts in the L direction, the sleeve 13 can be stopped more stably. Further, in the lens driving device 1, the sleeve 13 is not stopped by colliding with a collision material (buffer material) or the like, but is stopped using a balance between electromagnetic force and elastic force. Therefore, it is possible to prevent the occurrence of a collision sound.

(Configuration of the contact surface on the movable body 3 side and the reference surface on the support body 2 side)
FIG. 5 is an explanatory diagram showing changes in hardness when UV irradiation is performed on the sleeve 13 or the like. FIG. 6 is an explanatory diagram showing a change in the infrared absorption spectrum when UV irradiation is performed on the sleeve 13 or the like.

  In the lens driving device 1 of the present embodiment, in the above operation, when the image side end portion of the sleeve 13 is brought into contact with the holder 19 during the pause period in which the magnetic driving mechanism 5 is stopped, first, FIG. 2) and the front surface side of the bottom plate portion 191 of the holder 19, the X side in the X direction with respect to the opening 190, the other side X2 in the X axis direction, and the Y axis direction. Reference planes 197 are formed at four positions adjacent to one side Y1 and the other side Y2 in the Y-axis direction. In the present embodiment, the reference surface 197 includes an end surface of a step portion 196 that protrudes from the bottom plate portion 191 toward the front side.

  On the other hand, in the movable body 3, as shown in FIG. 4, in the rear side portion of the sleeve 13, the four portions that overlap the reference surface 197 in the optical axis L direction are respectively projected to the rear side. 135 is formed, and the step portion 135 has an area smaller than the reference surface 197.

  Each of the four step portions 135 is formed with a columnar protrusion 137 protruding toward the rear side, and the image side end portion of the sleeve 13 is held by the holder 19 by the front end surface of the protrusion 137. An abutting surface 137a that abuts on the reference surface 197 when abutting on is formed. In this embodiment, two contact surfaces 137 a are formed on each of the four step portions 135, and a total of eight contact surfaces 137 a are formed on the sleeve 13. For this reason, a step 135 having an area smaller than the reference surface 197 on the support 2 side is provided on the movable body 3 side. However, when the image side end of the sleeve 13 abuts against the holder 19, The tip surface (contact surface 137a) of the protrusion 137 and the reference surface 197 are in contact with each other, and the contact area is further narrowed.

For example, the reference surface 197 on the support 2 side and the stepped portion 135 on the moving body 3 side have an overlap area of 0.984 mm ² in total, but the tip surface (contact surface) of the protrusion 137 137a) and the reference surface 197 have a total contact area of 0.248 mm ² .

In the present embodiment, at least one of the contact surface 137a and the reference surface 197 is subjected to a process for reducing the suction force between the contact surface 137a and the reference surface 197. In this embodiment, as a process for reducing the suction force, at least one of the contact surface 137a and the reference surface 197 is subjected to a UV irradiation process. In this embodiment, the UV irradiation treatment uses a single wavelength light source of 250 nm, the standard setting as the integrated light quantity is 25.56 to 38.75 J / cm ² , and the lower limit setting is 21.2 to 31.8 J / cm ² . The effective band of the UV wavelength is set to the above wavelength because it has been confirmed that there is no effect in a spot UV device or a wavelength 172 nm excimer laser in which 300 nm or less is cut.

  More specifically, in this embodiment, since the sleeve 13 is made of a resin such as a liquid crystal polymer resin, a polycarbonate resin, or a polyamide resin, before assembling the lens driving device 1, the sleeve 13 is a light component alone. UV irradiation is performed from the rear side in the axis L direction. For this reason, the contact surface 137a is a surface irradiated with UV. Therefore, even when the contact surface 137a is contaminated when the lens driving device 1 is assembled, the contact surface 137a can be easily and reliably cleaned by the subsequent cleaning, so that it is adsorbed to the reference surface 197. The power is small. For example, even when the lens driving device 1 is assembled, even if the solder flux smoke generated during soldering contacts the contact surface 137a and the contact surface 137a is contaminated, the cleaning is performed by isopropyl alcohol or the like thereafter. Since the contact surface 137a is a clean surface, the attractive force with the reference surface 197 is small.

  However, since UV irradiation is performed on the sleeve 13 from the rear side in the optical axis L direction, when the sleeve 13 is viewed from the side where the contact surface 137a is located (the rear side in the optical axis L direction), UV is not irradiated to the shaded part such as the front end face.

  Here, according to the result of repeated execution by the inventor of the present application, when the UV irradiation treatment is performed on the contact surface 137a of the sleeve 13, the region of the sleeve 13 where the UV irradiation is performed and the UV irradiation are performed. There is a difference in hardness from the undisclosed area. More specifically, FIG. 5A shows a case where the sleeve 13 made of a liquid crystal polymer resin is subjected to UV irradiation (untreated), a case where the sleeve 13 is passed through a UV irradiation furnace five times (5 pass), and The hardness when the sleeve 13 made of liquid crystal polymer resin is passed through the UV irradiation furnace 10 times (10 pass) is compared. As can be seen from FIG. 5A, when the sleeve 13 is irradiated with UV, the hardness increases. Therefore, whether or not the UV irradiation process is performed on the contact surface 137a of the sleeve 13 depends on the contact surface 137a of the sleeve 13 and the side where the contact surface 137a is located (the rear side in the optical axis L direction). ) Can be determined by measuring the hardness of each of the shaded portions. That is, when the UV irradiation process is performed on the contact surface 137a of the sleeve 13, the hardness of the contact surface 137a of the sleeve 13 is higher than the hardness of the shaded area. Therefore, when the hardness of the contact surface 137a of the sleeve 13 is higher than the hardness of the shaded area, it can be determined that the UV irradiation process is performed on the contact surface 137a of the sleeve 13.

In addition, according to the results repeatedly performed by the inventor of the present application, infrared spectroscopic analysis is performed by a reflective infrared spectrophotometer in the region of the sleeve 13 where UV irradiation is performed and in the region where UV irradiation is not performed. There is a difference in the absorption peak position in the wave number range when performing. For example, when the sleeve 13 is made of a liquid crystal polymer resin, infrared spectrophotometry is performed with a reflective infrared spectrophotometer in the region of the sleeve 13 where UV irradiation is performed and in the region where UV irradiation is not performed. there is a difference in the absorption peak located wavenumber range of 1743cm ^-1 from 1728 cm ^-1 when performing. More specifically, FIG. 6A shows an infrared absorption spectrum when UV irradiation is not performed on the sleeve 13 made of a liquid crystal polymer resin, and FIG. An infrared absorption spectrum when UV irradiation is performed on the sleeve 13 is shown. As can be seen from FIGS. 6A and 6B, when the sleeve 13 is not irradiated with UV, an absorption peak exists at 1737 cm ⁻¹ , but when the sleeve 13 is irradiated with UV, the absorption peak appears at 1737 cm ^−1. Does not exist, and an absorption peak appears at 1732 cm ⁻¹ . Therefore, whether or not the UV irradiation process is performed on the contact surface 137a of the sleeve 13 depends on the contact surface 137a of the sleeve 13 and the side where the contact surface 137a is located (the rear side in the optical axis L direction). This can be determined by performing infrared spectroscopic analysis on each of the portions that are shaded when viewed from the above. That is, as a result of infrared spectroscopic analysis, 1728 cm ⁻¹ between the contact surface 137a of the sleeve 13 and a portion that is shaded when the sleeve 13 is viewed from the side where the contact surface 137a is located. When there is a difference in absorption peak position in the wave number range from 1743 cm ⁻¹ , it can be determined that the UV irradiation process is performed on the contact surface 137 a of the sleeve 13. Here, although the above-mentioned peak is considered to be a peak derived from an ester group, the reason why the peak position is shifted by UV irradiation has not been clarified.

  In this embodiment, since the holder 19 is made of a resin such as a liquid crystal polymer resin, a polycarbonate resin, or a polyamide resin, the holder 19 is in the state of a single component in the optical axis L direction before assembling the lens driving device 1. UV irradiation is performed from the front side. For this reason, the reference surface 197 is a surface irradiated with UV. Accordingly, even when the reference surface 197 is contaminated when the lens driving device 1 is assembled, the reference surface 197 can be easily and reliably cleaned by the subsequent cleaning, so that the adsorbing force with the contact surface 137a. Is small. For example, even when the lens driving device 1 is assembled, even if solder smoke smoke generated during soldering contacts the reference surface 197 and the reference surface 197 is contaminated, the reference surface 197 is washed by isopropyl alcohol or the like thereafter. Since the surface becomes a clean surface, the adsorption force with the contact surface 137a is small.

  However, in the holder 19, since the UV irradiation is performed from the front side in the optical axis L direction, when the holder 19 is viewed from the side where the reference surface 197 is located (the front side in the optical axis L direction), the rear end surface of the holder 19 For example, the shaded portion is not irradiated with UV.

  Here, in the holder 19 made of liquid crystal polymer resin, as in the case of the sleeve 13 made of liquid crystal polymer resin, when the UV irradiation treatment is performed on the reference surface 197, the UV irradiation region of the holder 19 and the UV are treated. There is a difference in hardness from a region where no irradiation is performed. More specifically, in FIG. 5B, when the holder 19 is irradiated with UV (untreated), when the holder 19 is passed through the UV irradiation furnace five times (5 pass), and when the holder 19 is irradiated with UV. The hardness when passing through the furnace 10 times (10 pass) is compared. As can be seen from FIG. 5B, when the holder 19 is irradiated with UV, the hardness increases. Therefore, when the hardness of the reference surface 197 of the holder 19 is higher than the hardness of the shaded region, it can be determined that the UV irradiation process is performed on the reference surface of the holder 19.

In addition, in the holder 19 made of liquid crystal polymer resin, similarly to the sleeve 13 made of liquid crystal polymer resin, the region irradiated with UV and the region not irradiated with UV are subjected to infrared by a reflective infrared spectrophotometer. from 1728 cm ^-1 when performing a spectral analysis to the wavenumber range of 1743cm ^-1 is a difference in the absorption peak position. Accordingly, in the result of infrared spectroscopic analysis, between the reference surface 197 of the holder 19 and the portion which is shaded when the holder 19 is viewed from the side where the reference surface 197 is located, 1728 cm ⁻¹ to 1743 cm. ^When there is a difference in absorption peak position in the wave number region of ⁻¹ , it can be determined that the UV irradiation process is performed on the reference surface 197 of the holder 19.

In the above description, the case where the sleeve 13 and the holder 19 are made of liquid crystal polymer resin has been described. However, when the sleeve 13 and the holder 19 are made of resin other than the liquid crystal polymer resin, for example, the sleeve 13 and the holder 19 are made of polyamide. The same applies to the case of resin. In this case, when UV irradiation is not performed on the sleeve 13 or the holder 19 made of polyamide resin, an absorption peak exists at 1635 cm ⁻¹ , but when UV irradiation is performed on the sleeve 13 or the holder 19, an absorption peak occurs at 1635 cm ^−1. Absorption peak appears at 1627 cm ⁻¹ .

(Drive characteristics)
FIG. 7 is an explanatory view showing the drive characteristics of the lens drive device 1 to which the present invention is applied, and shows the relationship between the drive current value supplied to the coils 31 and 32 of the magnetic drive mechanism 5 and the displacement amount of the moving body 3. It is a graph.

In this embodiment, when the image side end portion of the sleeve 13 abuts against the holder 19, it is the tip surface (abutment surface 137 a) of the protrusion 137 and the reference surface 197 that are in contact with each other. Is narrow. Further, UV irradiation is performed on the contact surface 137a and the reference surface 197 as a process for reducing the attractive force between the contact surface 137a and the reference surface 197. For this reason, since the attractive force between the contact surface 137a and the reference surface 197 is small, the lens driving device 1 exhibits the driving characteristics shown in FIG.

  More specifically, the contact surface 137a of the sleeve 13 used for the movable body 3 and the reference surface 197 of the holder 19 used for the support body 2 in a section where the level of the drive current supplied to the coils 31 and 32 is low. When the drive current to the coils 31 and 32 of the magnetic drive mechanism 5 is gradually increased from the contacted state, the drive current value and the displacement of the moving body have a relationship indicated by an arrow L1 in FIG. On the other hand, when the drive current to the coils 31 and 32 of the magnetic drive mechanism 5 is gradually decreased from the state where the contact surface 137a of the sleeve 13 and the reference surface 197 of the holder 19 are separated from each other, The displacement amount of the moving body has a relationship indicated by an arrow L2 in FIG. Here, as can be seen by comparing the relationship indicated by the arrow L1 with the relationship indicated by the arrow L2, the drive current to the coils 31 and 32 is gradually increased from the state where the contact surface 137a and the reference surface 197 are in contact with each other. When the contact surface 137a and the reference surface 197 are separated from each other, the movement start current value I1 (mA) and the drive current to the coils 31 and 32 from the state where the contact surface 137a and the reference surface 197 are separated from each other Between the contact end surface 137a and the reference surface 197 when the contact surface 137a and the reference surface 197 are in contact with each other, the difference due to the adsorption force between the contact surface 137a and the reference surface 197 Although ΔI5 exists, in this embodiment, the difference ΔI5 is extremely small.

  Accordingly, it is possible to realize the lens driving device 1 in which the difference ΔI5 between the movement start current value I1 (mA) and the movement end current value I2 (mA) is small. Here, just by directly managing the absolute value of the difference ΔI 5, it is not possible to properly manage the suction force in various types of lens driving devices 1. That is, if the thrust constant (gf / mA) when the moving body 3 is driven by the magnetic drive mechanism 5 is changed, the difference ΔI5 is changed even if the attractive force is constant. Therefore, in this embodiment, the value obtained by multiplying the difference ΔI5 by the thrust constant (gf / mA) when the moving body 3 is driven by the magnetic drive mechanism 5 is managed, and the value is 0.2 gf or less. The lens driving device 1 is realized.

  For example, according to this embodiment, it is possible to realize the lens driving device 1 having a thrust constant (gf / mA) of 0.0188 (gf / mA) and a difference ΔI5 of 2.3 (mA). When the difference ΔI5 is multiplied by a thrust constant (gf / mA), the value is 0.043, which is 0.2 gf or less. The value obtained by multiplying the difference ΔI5 by the thrust constant (gf / mA) is a value obtained by converting the difference ΔI5 into a load, and is suitable for management of the adsorption force.

  If the value obtained by multiplying the difference ΔI5 by the thrust constant (gf / mA) is 0.2 gf or less, the adsorption force between the moving body 3 and the support body 2 is small. Even when the moving body 3 is moved directly to a predetermined position from the initial state in which the moving body 3 contacts in the optical axis L direction, the position of the moving body 3 can be controlled with high accuracy.

  Therefore, in a section in which the level of the drive current supplied to the coils 31 and 32 is low, the moving body 3 is moved directly to a predetermined position from the initial state where the moving body 3 contacts the support body 2 in the optical axis L direction. Even in this case, the position of the moving body 3 can be accurately controlled.

In this embodiment, the value obtained by dividing the thrust constant (gf / mA) when the moving body 3 is driven by the magnetic drive mechanism 5 by the contact area (mm ² ) between the contact surface 137a and the reference surface 197 is 0.02 ((gf / mA) / mm ² ) or more. For example, in thrust constant (gf / mA) is 0.0188 (gf / mA), since the contact area between the contact surface 137a and the reference surface 197 (mm ²⁾ is 0.248Mm ^2, thrust constant (gf / mA) divided by the contact area (mm ² ) between the contact surface 137a and the reference surface 197 is 0.076 ((gf / mA) / mm ² ),
0.02 ((gf / mA) / mm ² ) or more. That is, although the thrust constant (gf / mA) is large, the contact area (mm ² ) between the contact surface 137a and the reference surface 197 is small. Therefore, the adsorption force between the moving body 3 and the support body 2 can be efficiently reduced.

If managed based on such values, the thrust constant (gf / mA) and the contact area (mm ² ) between the contact surface 137a and the reference surface 197 can be managed as a balance of both, so that the movable body 3 and the support body 2 It is effective to suppress the influence of the adsorption force of Further, a value obtained by dividing the thrust constant (gf / mA) when the moving body 3 is driven by the magnetic drive mechanism 5 by the contact area (mm ² ) between the contact surface 137a and the reference surface 197 is 0.02 ( If it is set to (gf / mA) / mm ² ) or more, the moving body 3 comes into contact with the support 2 in the direction of the optical axis L because it is hardly affected by the adsorption force between the moving body 3 and the support 2. Even when the moving body 3 is moved directly to a predetermined position from the initial state, the position of the moving body 3 can be accurately controlled.

(Main effects of this form)
As described above, in the lens driving device 1 of the present embodiment, since the adsorption force between the moving body 3 and the support body 2 is reduced, the moving body 3 contacts the support body 2 in the optical axis L direction. Even when the moving body 3 is moved directly to a predetermined position from the initial state, the position of the moving body 3 can be accurately controlled. For this reason, the position of the moving body 3 can be controlled in a section where the level of the drive current supplied to the coils 31 and 32 is low. Therefore, there is an advantage that power consumption necessary for driving the magnetic drive mechanism 5 can be reduced.

(Other embodiments)
In the above embodiment, the UV irradiation process is adopted as the process for reducing the attractive force between the contact surface 137a and the reference surface 197. However, as the process for the contact surface 137a and the reference surface 197, sandpaper, sandblast, etc. A surface roughening process using a plasma, a surface roughening process using a plasma discharge, a corona discharge, laser irradiation, or the like, or a surface roughening process using a matte processing by a die processing may be used.

  In the above-described embodiment, the process of reducing the suction force is performed on both the contact surface 137a and the reference surface 197. However, the suction force is applied to one of the contact surface 137a and the reference surface 197. You may perform the process to reduce.

DESCRIPTION OF SYMBOLS 1 Lens drive device 2 Support body 3 Moving body 5 Magnetic drive mechanism 13 Sleeve 14x Rear side spring member 14y Front side spring member 17 Magnet 18 Yoke 19 Holder 31 Coil 32 Coil 137a Contact surface 197 Reference surface

Claims (17)

A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
The movement start current value when the contact surface and the reference surface are separated when the drive current to the coil of the magnetic drive mechanism is gradually increased from the state where the contact surface and the reference surface are in contact with each other (MA) when the contact surface comes into contact with the reference surface when the drive current to the coil of the magnetic drive mechanism is gradually reduced from the state where the contact surface is separated from the reference surface The value obtained by multiplying the difference from the movement end current value (mA) by a thrust constant (gf / mA) when the moving body is driven by the magnetic drive mechanism is 0.2 gf or less. A lens driving device. A value obtained by dividing the thrust constant (gf / mA) by the contact area (mm ² ) between the contact surface and the reference surface is 0.02 ((gf / mA) / mm ² ) or more. The lens driving device according to claim 1, wherein:   The at least one of the contact surface and the reference surface is composed of a tip end surface of a protrusion protruding from one side of the movable body and the support body toward the other side. Or the lens drive device of 2.   4. The process according to claim 1, wherein at least one of the contact surface and the reference surface is subjected to a process for reducing an adsorption force between the contact surface and the reference surface. 5. The lens driving device according to one item.   4. The lens driving device according to claim 1, wherein at least one of the contact surface and the reference surface is subjected to a UV irradiation process. 5.   Between the contact surface and the portion that is shaded from the contact surface side in the movable body, and between the reference surface and the portion that is shaded from the reference surface side in the support body. The lens driving device according to claim 1, wherein at least one of them has a difference in hardness.   Between the contact surface and the portion that is shaded from the contact surface side in the movable body, and between the reference surface and the portion that is shaded from the reference surface side in the support body. 4. The lens driving device according to claim 1, wherein at least one of them has a difference in absorption peak position in a wavenumber region when infrared spectroscopic analysis is performed. 5. The lens driving device according to claim 7, wherein the difference between the absorption peak positions is in a wave number range of 1728 cm ⁻¹ to 1743 cm ⁻¹ .   4. The lens driving device according to claim 1, wherein at least one of the contact surface and the reference surface is subjected to a roughening process. 5. A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
A value obtained by dividing a thrust constant (gf / mA) when the moving body is driven by the magnetic drive mechanism by a contact area (mm ² ) between the contact surface and the reference surface is 0.02 ((gf / MA) / mm ² ) or more. A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
At least one of the contact surface and the reference surface is subjected to a process for reducing the attractive force between the contact surface and the reference surface. A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
At least one of the contact surface and the reference surface is subjected to a UV irradiation process. A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
Between the contact surface and the portion that is shaded from the contact surface side in the movable body, and between the reference surface and the portion that is shaded from the reference surface side in the support body. A lens driving device characterized in that at least one of them has a difference in hardness. A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
Between the contact surface and the portion that is shaded from the contact surface side in the movable body, and between the reference surface and the portion that is shaded from the reference surface side in the support body. A lens driving device characterized in that at least one of them has a difference in absorption peak position in a wave number region when infrared spectroscopic analysis is performed. The lens driving device according to claim 14, wherein the difference between the absorption peak positions is in a wave number range of 1728 cm ⁻¹ to 1743 cm ⁻¹ . A support, a moving body including a lens, a magnetic drive mechanism that magnetically drives the moving body with respect to the support in the lens optical axis direction, and urges the moving body to one side in the optical axis direction. A spring member that is in an initial state in which the contact surface of the movable body contacts the reference surface of the support in the optical axis direction when the magnetic drive mechanism is in a stopped state,
At least one of the contact surface and the reference surface is subjected to a roughening process.   The at least one of the abutment surface and the reference surface includes a tip end surface of a protrusion protruding from one side of the movable body and the support body toward the other side. The lens drive device as described in any one of thru | or 16.

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