WO2021120109A1

WO2021120109A1 - Lens driving device, camera device, and electronic apparatus

Info

Publication number: WO2021120109A1
Application number: PCT/CN2019/126639
Authority: WO
Inventors: Yoji Okazaki
Original assignee: Guangdong Oppo Mobile Telecommunications Corp., Ltd.
Priority date: 2019-12-19
Filing date: 2019-12-19
Publication date: 2021-06-24
Also published as: CN114746788B; CN114746788A

Abstract

A lens driving device (10) includes a lens moving mechanism (100), a shaft member (250) and a lubricant. The lens moving mechanism (100) is a mechanism to which a lens (500) is attached. The shaft member (250) is inserted into the lens moving mechanism (100) and is configured to guide the lens moving mechanism (100) so that the lens moving mechanism (100) can move along an optical axis direction (z) of the lens (500). The lubricant is disposed in a contact portion between the shaft member (250) and the lens moving mechanism (100). At least part of the lens moving mechanism (100) which contacts the shaft member (250) consists of insulation material containing micro-reinforcing fibers.

Description

LENS DRIVING DEVICE, CAMERA DEVICE, AND ELECTRONIC APPARATUS

FIELD

The present disclosure relates to a lens driving device, a camera device and an electronic apparatus.

BACKGROUND

In recent years, a camera device with a large lens and a large image sensor (e.g. 1/1.4 inches or more) for high image quality has been used in an electronic apparatus such as a smartphone. Camera device is used not only to take a still picture, but also for taking a video. Video mode has become popular in recent years, but the video mode consumes more power than still image mode since it requires an image stabilization etc. Further, various functions have been added to a mobile electronic apparatus such as smartphone, which leads to an increase of power consumption. Therefore, it is critical to reduce power consumption in an electronic apparatus with a camera device such as smartphone.

Camera device’s operations include the Auto Focus (AF) operation and the Optical Image Stabilizer (OIS) operation. In the AF operation, a position of the lens in an optical axis direction (the Z direction) is adjusted. In the OIS operation, a position of the lens in a direction perpendicular to the optical axis direction (the X direction, the Y direction) is adjusted.

Camera device adopts Slide structure type actuator (i.e. Slide-ACT) . Therefore, power consumed by camera device during the AF operation and the OIS operation is greatly affected by friction force between members constituting the camera device.

FIG. 17 shows the Stribeck curve well known to explain friction coefficient between two surfaces in contact. The Stribeck curve shows how friction coefficient (μ) changes depending on a load (P) acting between the surfaces, a sliding speed (v) of the surfaces, and a viscosity (η) of a lubricant between the surfaces.

As shown in FIG. 17, the friction state between the surfaces is divided into three regions: Boundary lubrication region R1, Mixed lubrication region R2 and Hydrodynamic lubrication region R3.

In the Boundary lubrication region R1, there is no lubricant between the two surfaces in contact. In Mixed lubrication region R2, the two surfaces in contact are separated by a very thin lubricant film, resulting in partial solid contact. In Hydrodynamic lubrication region R3, a sufficient thick lubricant film is formed between the two surfaces in contact. The lubricant film is enough thick compared to roughness of the surfaces.

In the Hydrodynamic lubrication region R3, friction coefficient (μ) increases in proportion to the speed (v) and the viscosity (η) , and decreases in inverse proportion to the load (P) .

Further, according to the Stribeck theory, the friction coefficient increases as the load decreases in the region R3. In a camera device, a load (lens and its support member etc. ) is very low. As a result, in a camera device, the friction coefficient is large even if a lubricant is used. This is one of the reasons that prevents low power consumption of an electronic apparatus with a camera device such as smartphone.

SUMMARY

The present disclosure aims to solve at least one of the technical problems mentioned above. Accordingly, the present disclosure needs to provide a lens driving device, a camera device and an electronic apparatus.

In accordance with the present disclosure, a lens driving device may include:

a lens moving mechanism to which a lens is attached;

a shaft member inserted into the lens moving mechanism, the shaft member being configured to guide the lens moving mechanism so that the lens moving mechanism can move along an optical axis direction of the lens; and

a lubricant disposed in a contact portion between the shaft member and the lens moving mechanism, wherein

at least part of the lens moving mechanism which contacts the shaft member includes insulation material containing micro-reinforcing fibers.

In some embodiments, the insulation material may contain solid fluorine oil.

In some embodiments, the micro-reinforcing fibers may be potassium titanate fibers.

In some embodiments, the lubricant may be fluorine oil.

In some embodiments, the fluorine oil is a mixture of a solid fluorine oil and a liquid fluorine oil.

In some embodiments, the insulation material may be Liquid Crystal Polymer (LCP) .

In some embodiments, the shaft member may be made of stainless steel.

In some embodiments, the lens moving mechanism includes:

a lens support member configured to support the lens;

a first moving member engaged with the lens support member so that the lens support member can move in a first direction orthogonal to an optical axis direction of the lens; and a second moving member engaged with the first moving member so that the first moving member can move in a second direction orthogonal to the optical axis direction and the first direction.

In some embodiments, the second moving member may consist of Liquid Crystal Polymer (LCP) .

In some embodiments, the shaft member may include a first shaft member and a second shaft member,

the first shaft member is inserted into an insertion hole which penetrates the second moving member in the optical axis direction, and

the second shaft member is inserted into an insertion groove which is provided with the second moving member and extends along the optical axis direction.

In some embodiments, the lens support member may consist of Liquid Crystal Polymer (LCP) .

In some embodiments, the first moving member may consist of Liquid Crystal Polymer (LCP) .

In some embodiments, the lens driving device may further include a driving mechanism configured to house the lens moving mechanism and to move the lens moving mechanism in the optical axis direction.

In some embodiments, the driving mechanism may move the lens moving mechanism at an initial speed of 1.0 mm/sec or more.

In some embodiments, the driving mechanism may include:

a base;

a flexible printed board wrapped around an outer surface of the base;

a coil mounted on an inner surface of the flexible printed board;

a magnetic member made of magnetic substance and fixed to the base, the magnetic member having an extending portion, an engaging hole being provided with the extending portion; and

a magnet fixed to a side surface of the second moving member to face the magnet member,

and wherein

one end of the shaft member is fixed to the base, and the other end of the shaft member is inserted into the engaging hole, and

the second moving member is pressed against the shaft member by an adsorption force orthogonal to the optical axis direction generated between the magnet and the magnetic member.

In some embodiments, the base may include a frame member and a metal plate engaged with the frame member, a positioning hole may be provided with the metal plate, and one end of the shaft member may be inserted into the positioning hole and caulked to the metal plate.

In accordance with the present disclosure, a camera device may include:

the lens driving device; and

the lens attached to the lens moving mechanism.

In accordance with the present disclosure, an electronic apparatus may include the camera device.

In accordance with the present disclosure, a lens driving device may include:

a lens support member configured to support a lens;

a first moving member engaged with the lens support member so that the lens support member can move in a first direction orthogonal to an optical axis direction of the lens;

a second moving member engaged with the first moving member so that the first moving member can move in a second direction orthogonal to the optical axis direction and the first direction;

a first lubricant disposed in a contact portion between the lens support member and the first moving member; and

a second lubricant disposed in a contact portion between the first moving member and the second moving member, wherein

the lens support member and the first moving member include a first insulation material containing micro-reinforcing fibers at least in a portion in contact with each other, and

the first moving member and the second moving member include a second insulation material containing micro-reinforcing fibers at least in a portion in contact with each other.

In some embodiments, the first and second insulation material may contain solid fluorine oil.

In some embodiments, a first guiding groove extending in the first direction may be formed on a lower surface of the lens support member, a first protrusion extending in the first direction may be formed on an upper surface of the first moving member, a second protrusion extending in the second direction may be formed on a lower surface of the first moving member, a second guiding groove extending in the second direction may be formed on an upper surface of the second moving member, the first protrusion may fit loosely into the first guiding groove, and the second protrusion may fit loosely into the second guiding groove, the first lubricant may be disposed in the first guiding groove and the second lubricant may be disposed in the second guiding groove.

In some embodiments, the first and second lubricant may be fluorine oil.

In some embodiments, the first and second insulation material may be Liquid Crystal Polymer (LCP) .

In some embodiments, the lens driving device may further include a driving mechanism configured to house the lens support member, the first moving member and the second moving member and to move the lens support member in the first direction and to move the lens support member and the first moving member in the second direction.

In some embodiments, the driving mechanism may move the lens support member at an initial speed of 1.0 mm/sec or more.

In some embodiments, the driving mechanism may move the lens support member and the first moving member at an initial speed of 1.0 mm/sec or more.

In some embodiments, the driving mechanism includes:

a base;

a flexible printed board wrapped around an outer surface of the base;

a coil mounted on an inner surface of the flexible printed board;

and wherein

In accordance with the present disclosure, a camera device may include:

the lens driving device; and

the lens attached to the lens moving mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of embodiments of the present disclosure will become apparent and more readily appreciated from the following descriptions made with reference to the drawings, in which:

FIG. 1 is an exploded perspective view of a camera device according to an embodiment of the present disclosure as viewed obliquely from above;

FIG. 2 is an exploded perspective view of a lens moving mechanism used in the camera device according to the embodiment of the present disclosure as viewed obliquely from above;

FIG. 3 is an exploded perspective view of the lens moving mechanism used in the camera device according to the embodiment of the present disclosure as viewed obliquely from below;

Fig. 4 is a partially enlarged plan view around an insertion hole provided with a second moving member in the lens moving mechanism;

Fig. 5 is a partially enlarged plan view around an insertion groove provided with a second moving member in the lens moving mechanism;

FIG. 6 is an exploded perspective view of a driving mechanism used in the camera device according to the embodiment of the present disclosure as viewed obliquely from above;

FIG. 7 is a perspective view a flexible printed board used in the driving mechanism according to the embodiment of the present disclosure;

FIG. 8 is an X direction sectional view along a line passing through the centers of two shaft members for illustrating the camera device according to the embodiment of the present disclosure;

FIG. 9A is a partial sectional view for illustrating the camera device according to the embodiment of the present disclosure, which is taken along the line A-A of FIG. 8;

FIG. 9B is a partial sectional view for illustrating the camera device according to the embodiment of the present disclosure, which is taken along the line B-B of FIG. 8;

FIG. 10 is a partial sectional view of the camera device according to a modification for illustrating a shaft member caulked to a metal plate.

FIG. 11 is an X direction sectional view for illustrating the camera device according to the embodiment of the present disclosure;

FIG. 12 is a Y direction sectional view for illustrating the camera device according to the embodiment of the present disclosure;

FIG. 13 is a schematic diagram illustrating a measurement system for measuring a friction force along an optical axis direction;

FIG. 14 is a graph showing the coefficient of static friction obtained by the measurement system illustrated in FIG. 13;

FIG. 15 is a schematic diagram illustrating a measurement system for measuring a friction force along a direction perpendicular to the optical axis direction;

FIG. 16 is a graph showing the coefficient of static friction obtained by the measurement system illustrated in FIG. 15;

FIG. 17 is a diagram showing a Stribeck curve.

DETAILED DESCRIPTION

Embodiments of the present disclosure will be described in detail and examples of the embodiments will be illustrated in the accompanying drawings. The same or similar elements and the elements having same or similar functions are denoted by like reference numerals throughout the descriptions. The embodiments described herein with reference to the drawings are explanatory, which aim to illustrate the present disclosure, but shall not be construed to limit the present disclosure.

A camera device according to one embodiment will be explained referring to FIG. 1.

FIG. 1 illustrates an exploded perspective view of a camera device 1 according to an embodiment of the present disclosure as viewed obliquely from above.

For the sake of convenience, an optical axis direction of a lens in the camera device is herein referred to as “Z direction” , a direction orthogonal to the optical axis direction is referred to as “X direction” , and a direction orthogonal to the Z direction and the X direction is referred to as “Y direction” . Further, an object side of an optical axis is referred to as “upper” side, and a side which is opposite to the upper side and on which an image sensor (not shown) is to be arranged is referred to as “lower” side.

As shown in FIG. 1, the camera device 1 includes a lens driving device 10 and a lens 500 mounted on the lens driving device 10. The camera device 1 includes an image sensor which is located at a lower side of the lens driving device 10. The camera device 1 is built in an electronic apparatus such as a smartphone, a tablet computer, a personal digital assistant (PDA) , etc.

The lens driving device 10 includes a lens moving mechanism 100 to which the lens 500 is attached, a driving mechanism 200 and a cover member 300.

The lens moving device 100 is configured to support the lens 500. The lens moving device 100 can be moved with the lens 500.

The driving mechanism 200 is configured to house the lens moving device 100 and to drive the lens moving mechanism 100 in the X direction, the Y direction and/or the Z direction by electromagnetic force generated between a magnet and a coil.

A shaft member 250 and a shaft member 260 are inserted into the lens moving mechanism 100 to guide the lens moving mechanism 100 along the optical axis direction of the lens 500. Therefore, the lens moving mechanism 100 can be moved along the Z direction.

The cover member 300 covers the lens moving mechanism 100 and the driving mechanism 200 (see FIG. 8) . The cover member 300 has an opening 301 into which the lens 500 is inserted. For example, the cover member 300 is made of stainless steel. The lens 500 is mounted on the lens driving mechanism 100 and inserted into the opening 301.

The camera device 1 is configured to perform the Auto Focus (AF) operation and the Optical Image Stabilizer (OIS) operation. In the AF operation, the driving mechanism 200 drives the lens moving mechanism 100 in the Z direction to move the lens 500 in an optical axis direction of the lens 500. In the OIS operation, the driving mechanism 200 drives the lens moving mechanism 100 in the X direction and the Y direction to move the lens 500 in a direction perpendicular to the optical axis direction.

Next, referring to the FIGs 2 to 5, the lens moving mechanism 100 will be explained in detail.

FIG. 2 illustrates an exploded perspective view of a lens moving mechanism 100 used in the camera device 1 as viewed obliquely from above. FIG. 3 illustrates an exploded perspective view of the lens moving mechanism 100 used in the camera device 1 as viewed obliquely from below. Fig. 4 is a partially enlarged plan view around an insertion hole 131 provided with a second moving member 130 in the lens moving mechanism 100. Fig. 5 is a partially enlarged plan view around an insertion groove 132 provided with the second moving member 130 in the lens moving mechanism 100.

The lens moving mechanism 100 includes a lens support member 110, a first moving member 120, a second moving member 130 and a cover member 140. The lens support member 110 is configured to support the lens 500.

As will be described in detail, the first moving member 120 is configured to be engaged with the lens support member 110 so that the lens support member 110 can move in a first direction orthogonal to an optical axis direction of the lens (i.e. the X direction) . The second moving member 130 is configured to be engaged with the first moving member 120 so that the first moving member 120 can move in a second direction orthogonal to the optical axis direction and the first direction (i.e. the Y direction) .

In the present embodiment, the lens support member 110, the first moving member 120 and the second moving member 130 consist of insulation material which is preferably excellent in friction resistance and wear resistance. Preferably, the insulation material is Liquid Crystal Polymer (LCP) . Of course, other insulation materials such as synthetic resin (thermoplastic resin etc. ) may be applicable.

Preferably, the insulation material may contain solid lubricant (e.g. solid fluorine oil) as a dopant in order to replenish lubricant into contact portions between the lens support member 110 and the first moving member 120, between the first moving member 120 and the second moving member 130, between the second moving member 130 (the insertion hole 131) and the shaft member 250, and between the second moving member 130 (the insertion groove 132) and the shaft member 260.

Preferably, the lens support member 110, the first moving member 120 and the second moving member 130 may be blackened by containing black material such as carbon so that light in the camera device 1 is not scattered. As a result, an undesirable phenomena (flare phenomena etc. ) can be eliminated.

Preferably, the lens support member 110, the first moving member 120 and the second moving member 130 may contain micro-reinforcing fibers as a filler in order to increase strength and reduce coefficient of friction. The micro-reinforcing fibers are, for example, potassium titanate fibers.

The potassium titanate fibers may be

developed by Otsuka Cheminal Co., Ltd. TISMO is ultra-fine potassium titanate fibers consisted of white needle crystal. TISMO’s fiber diameter is approximately 0.3～0.6μm, and its fiber length is approximately 10～20μm. Please note that there are some types of THSMO. For example, TISMO type D is composed of K ₂O· 8TiO ₂. TISMO type N is composed of K ₂O·6TiO ₂. One type of TISMO (type D or type N) may be used as a filler. Alternatively, a mixture of different types of TISMO may be used.

By using TISMO, excellent characteristics such as high strength, low hardness and surface flatness can be obtained, which leads to durability, smooth operation and reduction of friction scrap etc.

Preferably, it is desirable that the lens support member 110, the first moving member 120 and the second moving member 130 contain solid fluorine oil. Thereby, a friction coefficient can be reduced. Further, the friction coefficient can be kept low during use since fluorine oil is supplied even if a lubricant initially disposed in a contact portion or a guiding groove disappears.

In the present embodiment, the lens support member 110, the first moving member 120 and the second moving member 130 consist of

(Potassium Titanate Compound) which is a plastics composite material made by blending TISMO.

Please note that it is not necessary the micro-reinforcing fibers such as TISMO are not mixed with in the entire of the member. Regarding the AF operation, it is necessary that at least part of the lens moving mechanism 100 which contacts the shaft members 250 and 260 (i.e., an inner wall of the insertion hole 131 and the insertion groove 132 of the second moving member 130) contains micro-reinforcing fibers. Regarding the OIS operation, it is necessary that the lens support member 110 and the first moving member 120 comprise insulation material containing micro-reinforcing fibers at least in a portion in contact with each other (i.e. the guiding grooves 111, the protrusions 121) , and it is necessary that the first moving member 120 and the second moving member 130 comprise insulation material containing micro-reinforcing fibers at least in a portion in contact with each other (i.e. the protrusions 122, the guiding grooves 133) .

The lens support member 110 includes a plurality of guiding grooves 111, a lens mounting hole 112 and a plurality of concave portions 113. The lens 500 is inserted into the lens mounting hole 112 to be mounted to the lens support member 110.

As shown in FIG. 3, the guiding grooves 111 are formed on a lower surface of the lens support member 110. The guiding grooves 111 extend along the Y direction. In the present embodiment, the number of the guiding grooves 111 is four. Each of a plurality of protrusions 121 of the first moving member 120 fits loosely into the corresponding guiding groove 111, which allows the lens support member 110 to move in the Y direction.

The concave portions 113 are provided with side surfaces of the lens support member 110. As shown in FIG. 2, a plurality of

magnets

118a, 118b, 118c are fixed in the corresponding concave portions 113. A yoke plate may be laminated on the

magnets

118a, 118b, 118c.

The

magnets

118a, 118b and 118c receive an attraction force or a repulsion force by magnetic flux generated by

coils

232a, 232b and 232c (described later) provided with the driving mechanism 200. As a result, the lens support member 110 can move in the X direction or the Y direction by the magnetic force which the

magnets

118a, 118b, 118c receive. Please note that the magnet 118c may be omitted.

The first moving member 120 includes a plurality of

protrusions

121, 122 and an opening 123. The lens 500 supported by the lens support member 110 is inserted into the opening 123.

The protrusions 121 are formed on an upper surface of the first moving member 120, as shown in FIG. 2. The protrusions 121 extend along the Y direction. In the present embodiment, the number of the protrusions 121 is four. Each of the protrusions 121 fits loosely into the corresponding guiding grooves 111 of lens support member 110.

The protrusions 122 are formed on a lower surface of the first moving member 120, as shown in FIG. 3. The protrusions 122 extend along the X direction. In the present embodiment, the number of the protrusions 122 is four. Each of the protrusions 122 fits loosely into a guiding groove 133 formed on an upper surface of the second moving member 130.

The second moving member 130 includes the insertion hole 131, the insertion groove 132, the guiding grooves 133, an opening 134, a plurality of engaging protrusions 135, a concave portion 136 and a plurality of concave portions 137. The lens 500 supported by the lens support member 110 is inserted into the opening 134.

The insertion hole 131 is formed for a main guide of the lens moving mechanism 100. The insertion groove 132 is formed for a sub guide of the lens moving mechanism 100.

The insertion hole 131 is formed in one corner of the second moving member 130 to penetrate the second moving member 130 in the optical axis direction (i.e. the Z direction) . As shown in FIGs 1 and 4, the shaft member 250 is inserted into the insertion hole 131. Preferably, the insertion hole 131 has a substantially home base shape in plan view (see FIG. 4) , but the shape of the insertion hole 131 is not limited to this.

The insertion groove 132 is formed in another corner of the second moving member 130. The insertion groove 132 extends along the optical axis direction and opens on a side of the second moving member 130. As shown in FIGs. 1 and 5, the shaft member 260 is inserted into the insertion grove 132. Preferably, the insertion grove 132 has a substantially U-shaped opening in the X direction in plan view (see FIG. 5) , but the shape of the insertion groove 132 is not limited to this.

Further, an inner surface of the insertion groove 132 may be curved in an arc shape toward the shaft member 260 (see FIG. 9B) . In this case, the inner wall of the insertion groove 132 is swelled to form an annular contact portion 132a. The shaft member 260 contacts the second moving member 130 at the annular contact portion 132a. The shaft member 260 contacts at two points P3 and P4 from top view, as shown in FIG. 5.

An upper end of the shaft member 250 is inserted into an engaging hole 271a and a lower end of the shaft member 250 is inserted into a shaft fixing portions 211 of a base 210 (see FIG. 8) . Similarly, an upper end of the shaft member 260 is inserted into an engaging hole 271b and a lower end of the shaft member 260 is inserted into a shaft fixing portions 211 of the base 210.

The second moving member 130 is in a line contact with the shaft member 250 on an inner surface of the insertion hole 131. Also, the second moving member 130 is in contact with the shaft member 260 at the contact portion 132a on the inner surface of the insertion groove 132. As a result, the second moving member 130 is guided along the Z direction by the

shaft members

250 and 260.

As shown in FIG. 2, the guiding grooves 133 are formed on an upper surface of the second moving member 130. The guiding grooves 133 extend along the X direction. In the present embodiment, the number of the guiding grooves 133 is four. Each of the protrusions 122 of the first moving member 120 fits loosely into the corresponding guiding grooves 133, which allows the lens support member 110 and the first moving member 120 to move in the X direction.

The plurality of engaging protrusions 135 are formed on side surfaces of the second moving member 130. Each of the engaging protrusions 135 engages with an engaging hole 141a provided with an extending portion 141 of the cover member 140 such that the cover member 140 is fixed to the second moving member 130.

The concave portion 136 is provided with a side surface of the second moving member 130. As shown in FIG. 2, a magnet 138 is fixed in the concave portion 136 so that a principal surface of the magnet 138 is perpendicular to the Y axis. A yoke plate may be laminated on the magnet 138. The magnet 138 is divided into two pieces in the Z direction, as shown in FIG. 1. Each of the two pieces has an S pole and an N pole formed in the Y direction, and opposite polarities is provided between the two pieces.

A magnetic member 270 of the driving mechanism 200 (described later in detail) attracts the magnet 138 by magnetic force, thereby the lens moving mechanism 100 is attracted toward the driving mechanism 200 along the Y direction. As a result, the shaft member 250 contacts with the inner wall of the insertion hole 131 at two points P1 and P2 from top view, as shown in FIG. 4. Actually, the second moving member 130 contacts with the shaft member 250 at two lines extending along the Z direction. A normal force N acts on the shaft 250. Further, the shaft member 260 contacts with the contact portion 132a formed on the inner wall of the insertion groove 132, as shown in FIG. 5.

The second moving member 130 slides along the

shaft members

250 and 260, which allows the lens moving mechanism 100 to move in the Z direction for the AF operation.

As shown in FIG. 4 and FIG. 9A, a lubricant LC is disposed in a contact portion between the insertion hole 131 and the shaft member 250. Also, as shown in FIGs. 5 and FIG. 9B, a lubricant LC is disposed in a contact portion between the insertion groove 132 and the shaft member 260.

Further, a lubricant is disposed in a contact portion between the first moving member 120 and the second moving member 130. Specifically, as shown in FIG. 11, a lubricant LC1 (corresponding to a second lubricant in CLAIMS) is disposed in the guiding groves 133. Also, a lubricant (corresponding to a first lubricant in CLAIMS) is disposed in a contact portion between the lens support member 110 and the first moving member 120. Specifically, as shown in FIG. 12, a lubricant LC2 is disposed in the guiding grooves 111.

The material and characteristics of the lubricants LC1 and LC2 may be the same as those of the lubricant LC. Preferably, the lubricants LC, LC1 and LC2 are fluorine oil blended with fluororesin such as polytetrafluoroethylene (PTFE) . Fluorine oil has so low friction coefficient that friction force between members can be reduced. More preferably, the fluorine oil may be a mixture of a solid fluorine oil and a liquid fluorine oil.

The viscosity of fluorine oil can be changed by changing the ratio of solid fluorine oil and liquid fluorine oil. The solid fluorine oil contains a relatively large amount of PTFE with high molecular weight (i.e. long chain) . On the other hand, the liquid fluorine oil contains a relatively large amount of PTFE with low molecular weight (i.e. short chain) .

There is a possibility that thixotropy of the lubricants LC, LC1 and LC2 depend on a ratio between solid fluorine and liquid fluorine. In other words, thixotropy of the lubricants LC, LC1 and LC2 can be controlled by changing a ratio between solid fluorine and liquid fluorine.

The concave portions 137 are provided with a lower surface of the second moving member 130, as shown in FIG. 2. The magnetic members 139 made of magnetic substance such as stainless steel (SUS) are fixed in the concave portions 137. The magnetic members 139 are opposed to the

magnets

118a, 118b and 118c. The lens support member 110 and the first moving member 120 are pressed against the second moving member 130 by a magnetic force (adsorption force) between the magnetic members 139 and the

magnets

118a, 118b and 118c. As a result, a contact along the Z direction is maintained between the protrusion 121 and the guiding groove 111 and between the protrusion 122 and the guiding groove 133.

The cover member 140 covers the lens moving mechanism 100. The cover member 140 has a plurality of extending portions 141 and an opening 145. For example, the cover member 140 is made of metal such as stainless steel (SUS) . An engaging hole 141a is provided with each of the extending portion 141. Each of the engaging holes 141a is engaged with the corresponding engaging protrusions 135 of the second moving member 130. The opening 145 is provided at the center of the cover member 140. As shown in FIG. 1, the lens 500 is inserted into the opening 145.

In the above described embodiment, the lens support member 110 is configured to slide on the first moving member 120 along the Y direction and the first moving member 120 is configured to slide on the second moving member 130 along the X direction. It may be opposite. That is to say, the lens support member 110 may be configured to slide on the first moving member 120 along the X direction and the first moving member 120 may be configured to slide on the second moving member 130 along the Y direction. In this case, the guiding grooves 111 and the protrusions 121 extend along the X direction. The protrusions 122 and the guiding grooves 133 extend along the Y direction.

Next, referring to the FIGs 6 and 7, the driving mechanism 200 will be explained in detail. FIG. 6 is an exploded perspective view of a driving mechanism 200 used in the camera device 1 as viewed obliquely from above. FIG. 7 is a perspective view a flexible printed board 220 of the driving mechanism 200.

The driving mechanism 200 includes a base 210, the flexible printed board 220, a plurality of

coils

231, 232a, 232b, 232c, a plurality of

position detectors

241, 242a, 242b, the

shaft members

250 and 260, and the magnetic member 270.

As shown in FIG. 6, the base 210 has two shaft fixing portions 211 and an opening 212 on its bottom surface. A lower end of the shaft member 250 is inserted into the shaft fixing portion 211 to be fixed to the base 210. Similarly, a lower end of the shaft member 260 is fixed to the base 210 by the shaft fixing portion 211. In the present embodiment, the base 210 is made of LCP.

Preferably, as shown in FIG. 10, the base 210 may include a frame member 210a made of LCP and a metal plate 210b. The metal plate 210b may be engaged with the frame member 210a. A positioning hole H which penetrates the metal plate 210b is provided with the metal plate 210b. A lower end of the shaft member 250 (260) is inserted into the positioning hole H and directly metal-caulked to the metal plate 210b. As a result, a fixing strength between the shaft member 250 (260) and the metal plate 210b can be increased, which leads to a stabilization of the AF operation.

The flexible printed board 220 is folded and wrapped around the outer surface of the base 210, as shown in FIG. 6. The flexible printed board 220 has terminals 221 and terminals 222 on its lower end. The terminals 221 and the terminals 222 are provided on opposite sides of the Y axis. The

terminals

221, 222 are not covered by the cover member 300 and exposed to the outside to electrically connect a main board of an electronic apparatus.

The

coils

231, 232a, 232b and 232c are mounted on the inner surface of the flexible printed board 220. The coil 231 is disposed to face the magnet 138 fixed to the side surface of the second moving member 130. Magnetic field generated by the coil 231 acts on the second moving member 130 via the magnet 138 when the coil 231 is energized from a power source (not shown) through the terminals 221. As a result, a driving force for driving the second moving member 130 in the Z direction is generated between the coil 231 and the magnet 138. According to the driving force, the lens moving mechanism 100 moves in the Z direction with the lens 500 to perform the AF operation. Of course, a speed of the lens moving mechanism 100 along the Z direction can be increased by increasing the current flowing through the coil 231.

More precisely, the AF operation is performed using a position detector 241. As shown in FIG. 7, the position detector 241 is arranged next to the coil 231 and is configured to detect a Z directional position of the lens moving mechanism 100. The AF operation is performed based on the detecting result of the Z-position obtained from the position detector 241.

As described above, the lens moving mechanism 100 can be moved in the Z direction by energizing the coil 231, thereby the AF operation can be performed.

As shown in FIG. 7, the

coils

232a and 232c are mounted on an inner surface perpendicular to the X direction and the coil 232b is mounted on an inner surface perpendicular to the Y direction. The

coils

232a, 232b and 232c are used to drive the lens moving mechanism 100 (i.e. the lens support member 110) in the X direction and the Y direction. Please note that the coil 232c may be omitted.

The

coils

232a, 232b and 232c are energized from the power source through the terminals 222. As a result of the

coils

232a and 232c being energized, a driving force for driving the lens support member 110 in the X direction is generated between the

coils

232a and 232c and the

magnets

118a and 118c. According to the driving force in the X direction, the lens moving mechanism 100 moves in the X direction with the lens 500. Further, as a result of the coil 232b being energized, a driving force for driving the lens support member 110 in the Y direction is generated between the coil 232b and the magnet 118b. According to the driving force in the Y direction, the lens moving mechanism 100 moves in the Y direction with the lens 500. Of course, a speed of the lens moving mechanism 100 along the X direction or the Y direction can be increased by increasing the current flowing through the

coils

232a, 232b, 232c.

The OIS operation is performed using a position detector 242a and a position detector 242b. The position detector 242a is arranged at the center of the coil 232a and detects an X directional position of the lens moving mechanism 100. The position detector 242b is arranged at the center of the coil 232b and detects a Y directional position of the lens moving mechanism 100. The OIS operation is performed based on the detecting results of the X directional and the Y directional positions obtained from the

position detectors

242a and 242b.

As described above, the lens moving mechanism 100 can be moved in the X direction and in the Y direction by energizing the

coils

232a, 232b and 232c, thereby the OIS (Optical Image Stabilizer) operation can be performed.

Next, the magnetic member 270 will be explained in detail. The magnetic member 270 is made of magnetic substance such as stainless steel (SUS) . In the camera device 1, the magnetic member 270 is disposed in a gap between the flexible printed board 220 and the cover member 300 (see FIGs. 9 and 10) . The magnetic member 270 is provided on the outer side of the flexible printed board 220. The magnetic member 270 is opposed to the magnet 138 with the flexible printed board 220 and the coil 231 interposed therebetween.

The magnetic member 270 is fixed to the base 210. For example, a lower end of the magnetic member 270 may be inserted into an insertion groove (not shown) formed in the base 210.

As shown in FIG. 1, the magnetic member 270 has a extending portion 271 with which an engaging hole 271a and an engaging hole 271b are provided. An upper end of the shaft member 250 is inserted into the engaging hole 271a, and an upper end of the shaft member 260 is inserted into the engaging hole 271b.

An adsorption force is acted between the second moving member 130 and the

shaft members

250 and 260 when magnetic fluxes from the magnet 138 flow through the magnetic member 270. As a result, the second moving member 130 is pressed against the

shaft members

250 and 260. Specifically, by the adsorption force, the shaft member 250 is pressed against the inner surface of the insertion hole 131 and the shaft member 260 is pressed against the inner surface of the insertion groove 132.

Next, friction force acting between the second moving member 130 and the

shaft members

250, 260 will be explained.

Case 1: the optical axis direction of the lens 500 is parallel to a vertical direction (i.e. horizontal position) . In this case, the static friction force F _z is represented as the following formula (1) .

F _z = μ × AP (1)

Here, μ is a friction coefficient and AP is the adsorption force generated between the magnet 138 and the magnetic member 270.

Case 2: the optical axis direction of the lens 500 is orthogonal to a vertical direction (i.e. vertical position) . In this case, the static friction force F _z is represented as the following formula (2) .

F _z = μ × (AP + L) (2)

Here, L is a gravity of the lens moving mechanism 100 and the lens 500 on the

shaft members

250 and 260.

As is clear from the formulas (1) and (2) , the friction force in the case 1 is smaller than that of the case 2.

FIG. 13 is a schematic diagram illustrating a measurement system for measuring a friction force along the optical axis direction. Two shafts 900 are horizontally fixed to a support stage ST. The shafts 900 simulate the

shaft members

250 and 260. That is, the shafts 900 are made of stainless steel, and a diameter of the shafts 900 is the same as that of the

shaft members

250, 260. One of the shafts 900 is inserted into the insertion hole 131 and the other of the shafts 900 is inserted into the insertion groove 132, so that the lens moving mechanism 100 is supported by the two shafts 900. Lubricant has been applied to the insertion hole 131 and the insertion groove 132.

In the lens moving mechanism 100 to be measured, the lens support member 110, the first moving member 120 and the second moving member 130 consist of LCP blended with TISMO. Fluorine oil is used as the lubricant LC.

A weight W is hung from the lens moving mechanism 100 with a hook J. The weight W can be replaced with other weights to change a load (P) applied to the lens moving mechanism 100.

As shown in FIG. 13, the lens moving mechanism 100 is pushed by a push gauge PG. The push gauge PG records a maximum value of force applied to the lens moving mechanism 100 (i.e. maximum static friction force) , and an initial speed of the lens moving mechanism 100 when the lens moving mechanism 100 started to move.

Fig. 14 shows the result measured by the measurement system illustrated by FIG. 13. The horizontal axis of the graph is a weight (unit: g) of the weight W. Specifically, the graph in FIG. 14 shows the coefficient of static friction when a load applied to the lens moving mechanism 100 is changed. The coefficients of static friction are calculated based on the load and the measured pushing force.

Further, the graph in FIG. 14 shows three curves for different initial speed (i.e. 0.5 mm/s, 1.0 mm/sand 10 mm/s) of the lens moving mechanism 100. The result means that, for all three curves, the coefficient of static friction decreases as the load increases, which is consistent with the Stribeck curve in the Hydrodynamic lubrication region R3. From the result of the experiment, it was found that the friction coefficient is greatly reduced at an initial speed of 1.0 mm/sor more and that it is almost saturated at an initial speed of 10 mm/s.

The above result indicates that, the faster the lens moving mechanism 100 moves along the Z direction, the smaller coefficient of static friction becomes. That is, friction coefficient (μ) is in inverse proportion to the speed (v) . The trend seems to be contrary to the Stribeck curve in the Hydrodynamic lubrication region R3. This new phenomena can be understood that the friction force is mainly caused by thixotropy of fluorine oil in case of very low load weight and the thixotropy can be weakened by high sliding speed.

It is also considered that the decrease in viscosity accompanying the thixotropy of the lubricant LC affects the trend of friction coefficient. More specifically, the lubricant LC applied to the insertion hole 131 and the insertion groove 132 has thixotropy that lowers viscosity of the lubricant LC to the extent that a horizontal axis parameter η*v/P in the Stribeck curve decreases even if a sliding speed of the lens moving mechanism 100 along the optical axis direction increases. There is a possibility that thixotropy depends on a ratio between solid fluorine and liquid fluorine in the lubricant LC.

As described above, the friction coefficient decreases as the sliding speed of the lens moving mechanism 100 increases. Therefore, according to the embodiment, power consumption by performing the AF operation can be reduced since the coefficient of static friction between the lens moving mechanism 100 and the

shafts

250, 260 decreases by moving the lens moving mechanism 100 along the Z direction quickly (preferably 1.0 mm/sor more) .

Next, referring to FIG. 11, friction force acting between the lens support member 110 and the first moving member 120 will be explained.

The static friction force along the Y direction F _y is represented as the following formula (3) .

F _y = μ _y × (N _y + W _y) (3)

Here, μ _y is a friction coefficient, N _y is the adsorption force generated between the

magnets

118a, 118b, 118c and the magnetic members 139 and W _y is a load applied to the protrusion 121. W _y × 4 is equal to a gravity of the lens support member 110, the

magnets

118a, 118b, 118c and the lens 500.

Next, referring to FIG. 12, friction force acting between the first moving member 120 and the second moving member 130 will be explained.

The static friction force along the X direction F _x is represented as the following formula (4) .

F _x = μ _x × (N _x + W _x) (4)

Here, μ _x is a friction coefficient, N _x is the adsorption force generated between the

magnets

118a, 118b, 118c and the magnetic members 139 and W _x is a load applied to the guiding groove 133. W _x × 4 is equal to a gravity of the lens support member 110, the

magnets

118a, 118b, 118c, the first moving member 120 and the lens 500.

FIG. 15 is a schematic diagram illustrating a measurement system for measuring a friction force along a direction perpendicular to the optical axis direction. The lens moving mechanism 100 (specifically, the second moving member 130) is fixed on the support stage ST. A weight W is fixed on the lens support member 110. The weight W can be replaced with other weights to change a load (P) applied to the lens moving mechanism 100.

In the lens moving mechanism 100 to be measured, the lens support member 110, the first moving member 120 and the second moving member 130 consist of LCP blended with TISMO. Fluorine oil is used as the lubricants LC1 and LC2.

As shown in FIG. 15, the push gauge PG pushes the weight W along the Y direction. The push gauge PG records a maximum value of force applied to the weight W (i.e. maximum static friction force) , and an initial speed of the lens moving mechanism 100 when the lens moving mechanism 100 started to move.

Fig. 16 shows the result measured by the measurement system illustrated by FIG. 15. The horizontal axis of the graph is a weight (unit: g) of the weight W. The graph in FIG. 16 shows the coefficient of static friction when a load applied to the lens moving mechanism 100 is changed. The coefficients of static friction in FIG. 16 are calculated based on the load and the measured pushing force.

Further, the graph shows three curves for different initial speed (i.e. 0.5 mm/s, 1.0 mm/sand 10 mm/s) of the lens moving mechanism 100. The result means that, for all three curves, the coefficient of static friction decreases as the load increases, which is consistent with the Stribeck curve in the Hydrodynamic lubrication region R3. From the result of the experiment, it was found that the friction coefficient is greatly reduced at an initial speed of 1.0 mm/sor more and that it is almost saturated at an initial speed of 10 mm/s.

The above result also indicates that, the faster the lens moving mechanism 100 moves along the X or Y direction, the smaller coefficient of static friction becomes. That is, friction coefficient (μ) is in inverse proportion to the speed (v) . This trend seems to be contrary to the Stribeck curve in the Hydrodynamic lubrication region R3. The same reasons as the AF operation can be considered. That is to say, the friction force is mainly caused by thixotropy of fluorine oil in case of very low load weight and the thixotropy can be weakened by high sliding speed.

It is also considered that the lubricant LC2 disposed in the guiding groove 111 has thixotropy that lowers viscosity of the lubricant LC2 to the extent that a horizontal axis parameter η*v/P in the Stribeck curve decreases even if a sliding speed of the lens support member 110 along the Y direction increases. Namely, it is considered that the decrease in viscosity accompanying the thixotropy of the lubricant LC2 affects the trend of friction coefficient. More specifically, the lubricant LC2 disposed in the guiding grooves 111 has thixotropy that lowers viscosity of the lubricant LC2 to the extent that a horizontal axis parameter η*v/P in the Stribeck curve decreases even if a sliding speed of the lens support member 110 along the Y direction increases. There is a possibility that thixotropy depends on a ratio between solid fluorine oil component and liquid fluorine oil component in the lubricant LC1, LC2. It is clear that the same can be said for the lubricant LC1.

As described above, the friction coefficient decreases as the sliding speed of the lens moving mechanism 100 increases. Therefore, according to the embodiment, power consumption by performing the OIS operation along the Y direction can be reduced because the coefficient of static friction between the lens support member 110 and the first moving member 120 decreases by moving the lens support member 110 along the Y direction quickly (preferably 1.0 mm/sor more) . Further, power consumption by performing the OIS operation along the X direction can be reduced because the coefficient of static friction between the first moving member 120 and the second moving member 130 decreases by moving the first moving member 120 and the second moving member 130 along the X direction quickly (preferably 1.0 mm/sor more) .

In the description of embodiments of the present disclosure, it is to be understood that terms such as "central" , "longitudinal" , "transverse" , "length" , "width" , "thickness" , "upper" , "lower" , "front" , "rear" , "left" , "right" , "vertical" , "horizontal" , "top" , "bottom" , "inner" , "outer" , "clockwise" and "counterclockwise" should be construed to refer to the orientation or the position as described or as shown in the drawings under discussion. These relative terms are only used to simplify description of the present disclosure, and do not indicate or imply that the device or element referred to must have a particular orientation, or constructed or operated in a particular orientation. Thus, these terms cannot be constructed to limit the present disclosure.

In addition, terms such as "first" and "second" are used herein for purposes of description and are not intended to indicate or imply relative importance or significance or to imply the number of indicated technical features. Thus, the feature defined with "first" and "second" may comprise one or more of this feature. In the description of the present disclosure, "a plurality of" means two or more than two, unless specified otherwise.

In the description of embodiments of the present disclosure, unless specified or limited otherwise, the terms "mounted" , "connected" , "coupled" and the like are used broadly, and may be, for example, fixed connections, detachable connections, or integral connections; may also be mechanical or electrical connections ; may also be direct connections or indirect connections via intervening structures; may also be inner communications of two elements, which can be understood by those skilled in the art according to specific situations.

In the embodiments of the present disclosure, unless specified or limited otherwise, a structure in which a first feature is "on" or "below" a second feature may include an embodiment in which the first feature is in direct contact with the second feature, and may also include an embodiment in which the first feature and the second feature are not in direct contact with each other, but are contacted via an additional feature formed therebetween. Furthermore, a first feature "on" , "above" or "on top of" a second feature may include an embodiment in which the first feature is right or obliquely "on" , "above" or "on top of" the second feature, or just means that the first feature is at a height higher than that of the second feature; while a first feature "below" , "under" or "on bottom of" a second feature may include an embodiment in which the first feature is right or obliquely "below" , "under" or "on bottom of" the second feature, or just means that the first feature is at a height lower than that of the second feature.

Various embodiments and examples are provided in the above description to implement different structures of the present disclosure. In order to simplify the present disclosure, certain elements and settings are described in the above. However, these elements and settings are only by way of example and are not intended to limit the present disclosure. In addition, reference numbers and/or reference letters may be repeated in different examples in the present disclosure. This repetition is for the purpose of simplification and clarity and does not refer to relations between different embodiments and/or settings. Furthermore, examples of different processes and materials are provided in the present disclosure. However, it would be appreciated by those skilled in the art that other processes and/or materials may be also applied.

Reference throughout this specification to "an embodiment" , "some embodiments" , "an exemplary embodiment" , "an example" , "aspecific example" or "some examples" means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Thus, the appearances of the above phrases throughout this specification are not necessarily referring to the same embodiment or example of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

Any process or method described in a flow chart or described herein in other ways may be understood to include one or more modules, segments or portions of codes of executable instructions for achieving specific logical functions or steps in the process, and the scope of a preferred embodiment of the present disclosure includes other implementations, in which it should be understood by those skilled in the art that functions may be implemented in a sequence other than the sequences shown or discussed, including in a substantially identical sequence or in an opposite sequence.

The logic and/or step described in other manners herein or shown in the flow chart, for example, a particular sequence table of executable instructions for realizing the logical function, may be specifically achieved in any computer readable medium to be used by the instruction execution system, device or equipment (such as the system based on computers, the system comprising processors or other systems capable of obtaining the instruction from the instruction execution system, device and equipment and executing the instruction) , or to be used in combination with the instruction execution system, device and equipment. As to the specification, "the computer readable medium" may be any device adaptive for including, storing, communicating, propagating or transferring programs to be used by or in combination with the instruction execution system, device or equipment. More specific examples of the computer readable medium comprise but are not limited to: an electronic connection (an electronic device) with one or more wires, a portable computer enclosure (a magnetic device) , a random access memory (RAM) , a read only memory (ROM) , an erasable programmable read-only memory (EPROM or a flash memory) , an optical fiber device and a portable compact disk read-only memory (CDROM) . In addition, the computer readable medium may even be a paper or other appropriate medium capable of printing programs thereon, this is because, for example, the paper or other appropriate medium may be optically scanned and then edited, decrypted or processed with other appropriate methods when necessary to obtain the programs in an electric manner, and then the programs may be stored in the computer memories.

It should be understood that each part of the present disclosure may be realized by the hardware, software, firmware or their combination. In the above embodiments, a plurality of steps or methods may be realized by the software or firmware stored in the memory and executed by the appropriate instruction execution system. For example, if it is realized by the hardware, likewise in another embodiment, the steps or methods may be realized by one or a combination of the following techniques known in the art: a discrete logic circuit having a logic gate circuit for realizing a logic function of a data signal, an application-specific integrated circuit having an appropriate combination logic gate circuit, a programmable gate array (PGA) , a field programmable gate array (FPGA) , etc.

Those skilled in the art shall understand that all or parts of the steps in the above exemplifying method of the present disclosure may be achieved by commanding the related hardware with programs. The programs may be stored in a computer readable storage medium, and the programs comprise one or a combination of the steps in the method embodiments of the present disclosure when run on a computer.

In addition, each function cell of the embodiments of the present disclosure may be integrated in a processing module, or these cells may be separate physical existence, or two or more cells are integrated in a processing module. The integrated module may be realized in a form of hardware or in a form of software function modules. When the integrated module is realized in a form of software function module and is sold or used as a standalone product, the integrated module may be stored in a computer readable storage medium.

The storage medium mentioned above may be read-only memories, magnetic disks, CD, etc.

Although embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that the embodiments are explanatory and cannot be construed to limit the present disclosure, and changes, modifications, alternatives and variations can be made in the embodiments without departing from the scope of the present disclosure.

Claims

A lens driving device, comprising:

a lens moving mechanism to which a lens is attached;

a shaft member inserted into the lens moving mechanism, the shaft member being configured to guide the lens moving mechanism so that the lens moving mechanism can move along an optical axis direction of the lens; and

a lubricant disposed in a contact portion between the shaft member and the lens moving mechanism, wherein

at least part of the lens moving mechanism which contacts the shaft member comprises insulation material containing micro-reinforcing fibers.
The lens driving device according to claim 1, wherein the insulation material contains solid fluorine oil.
The lens driving device according to claim 1 or 2, wherein the micro-reinforcing fibers are potassium titanate fibers.
The lens driving device according to any one of claims 1 to 3, wherein the lubricant is fluorine oil.
The lens driving device according to claim 4, wherein the fluorine oil is a mixture of a solid fluorine oil and a liquid fluorine oil.
The lens driving device according to any one of claims 1 to 5, wherein the insulation material is Liquid Crystal Polymer (LCP) .
The lens driving device according to any one of claims 1 to 6, wherein the shaft member is made of stainless steel.
The lens driving device according to any one of claims 1 to 7, wherein the lens moving mechanism comprises:

a lens support member configured to support the lens;

a first moving member engaged with the lens support member so that the lens support member can move in a first direction orthogonal to an optical axis direction of the lens; and

a second moving member engaged with the first moving member so that the first moving member can move in a second direction orthogonal to the optical axis direction and the first direction.
The lens driving device according to claim 8, wherein the second moving member consists of Liquid Crystal Polymer (LCP) .
The lens driving device according to claim8 or 9, wherein the shaft member comprises a first shaft member and a second shaft member,

the first shaft member is inserted into an insertion hole which penetrates the second moving member in the optical axis direction, and

the second shaft member is inserted into an insertion groove which is provided with the second moving member and extends along the optical axis direction.
The lens driving device according to any one of claims 8 to 10, wherein the lens support member consists of Liquid Crystal Polymer (LCP) .
The lens driving device according to any one of claims 8 to 11, wherein the first moving member consists of Liquid Crystal Polymer (LCP) .
The lens driving device according to claim 8, further comprising a driving mechanism configured to house the lens moving mechanism and to move the lens moving mechanism in the optical axis direction.
The lens driving device according to claim 13, wherein the driving mechanism moves the lens moving mechanism at an initial speed of 1.0 mm/sec or more.
The lens driving device according to claim 13 or 14, wherein

the driving mechanism comprises:

a base;

a flexible printed board wrapped around an outer surface of the base;

a coil mounted on an inner surface of the flexible printed board;

a magnetic member made of magnetic substance and fixed to the base, the magnetic member having an extending portion, an engaging hole being provided with the extending portion; and

a magnet fixed to a side surface of the second moving member to face the magnet member,

and wherein

one end of the shaft member is fixed to the base, and the other end of the shaft member is inserted into the engaging hole, and

the second moving member is pressed against the shaft member by an adsorption force orthogonal to the optical axis direction generated between the magnet and the magnetic member.
The lens driving device according to claim 15, wherein the base comprises a frame member and a metal plate engaged with the frame member, a positioning hole is provided with the metal plate, and one end of the shaft member is inserted into the positioning hole and caulked to the metal plate.
A camera device, comprising:

the lens driving device according to any one of claims 1 to 16; and

the lens attached to the lens moving mechanism.
An electronic apparatus, comprising the camera device of claim 17.
A lens driving device, comprising:

a lens support member configured to support a lens;

a first moving member engaged with the lens support member so that the lens support member can move in a first direction orthogonal to an optical axis direction of the lens;

a second moving member engaged with the first moving member so that the first moving member can move in a second direction orthogonal to the optical axis direction and the first direction;

a first lubricant disposed in a contact portion between the lens support member and the first moving member; and

a second lubricant disposed in a contact portion between the first moving member and the second moving member, wherein

the lens support member and the first moving member comprise a first insulation material containing micro-reinforcing fibers at least in a portion in contact with each other, and

the first moving member and the second moving member comprise a second insulation material containing micro-reinforcing fibers at least in a portion in contact with each other.
The lens driving device according to claim 19, wherein the first and second insulation material contain solid fluorine oil.
The lens driving device according to claim 19 or 20, wherein

a first guiding groove extending in the first direction is formed on a lower surface of the lens support member,

a first protrusion extending in the first direction is formed on an upper surface of the first moving member,

a second protrusion extending in the second direction is formed on a lower surface of the first moving member,

a second guiding groove extending in the second direction is formed on an upper surface of the second moving member,

the first protrusion fits loosely into the first guiding groove, and the second protrusion fits loosely into the second guiding groove, and

the first lubricant is disposed in the first guiding groove and the second lubricant is disposed in the second guiding groove.
The lens driving device according to any one of claim 19 to 21, wherein the micro-reinforcing fibers are potassium titanate fibers.
The lens driving device according to any one of claims 19 to 22, wherein the first and second lubricant is fluorine oil.
The lens driving device according to claim 23, wherein the fluorine oil is a mixture of a solid fluorine oil and a liquid fluorine oil.
The lens driving device according to any one of claims 19 to 24, wherein the first and second insulation material are Liquid Crystal Polymer (LCP) .
The lens driving device according to any one of claims 19 to 25, further comprising a driving mechanism configured to house the lens support member, the first moving member and the second moving member and to move the lens support member in the first direction and to move the lens support member and the first moving member in the second direction.
The lens driving device according to claim 26, wherein the driving mechanism moves the lens support member at an initial speed of 1.0 mm/sec or more.
The lens driving device according to claim 26 or 27, wherein the driving mechanism move the lens support member and the first moving member at an initial speed of 1.0 mm/sec or more.
The lens driving device according to any one of claims 26 to 28, wherein

the driving mechanism comprises:

a base;

a flexible printed board wrapped around an outer surface of the base;

a coil mounted on an inner surface of the flexible printed board;

a magnetic member made of magnetic substance and fixed to the base, the magnetic member having an extending portion, an engaging hole being provided with the extending portion; and

a magnet fixed to a side surface of the second moving member to face the magnet member,

and wherein

one end of the shaft member is fixed to the base, and the other end of the shaft member is inserted into the engaging hole, and

the second moving member is pressed against the shaft member by an adsorption force orthogonal to the optical axis direction generated between the magnet and the magnetic member.
The lens driving device according to claim 29, wherein the base includes a frame member and a metal plate engaged with the frame member, a positioning hole is provided with the metal plate, and one end of the shaft member is inserted into the positioning hole and caulked to the metal plate.
A camera device, comprising:

the lens driving device according to any one of claims 19 to 30; and

the lens attached to the lens moving mechanism.
An electronic apparatus, comprising the camera device of claim 31.