Lens assembly, camera module and mobile electronic device

Abstract

The present application relates to a lens assembly comprising: a lens barrel formed of a first material; and a lens holder coupled to the lens barrel and formed of a second material, in which a bonding portion in which the lens barrel and the lens holder are bonded to each other includes a mixed layer in which the first material and the second material are mixed with each other, and the bonding portion includes one or more voids. The invention also relates to a camera module and a mobile electronic device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2018-0149306, filed on November 28, 2018, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety for all purposes. Technical Field

[0003] The present disclosure relates to a lens assembly, a camera module, and a mobile electronic device. Background Art

[0004] Generally, a camera module used in a mobile electronic device such as a smart phone includes a lens, a lens barrel in which the lens is mounted, and a lens holder supporting the lens barrel.

[0005] The method of connecting the lens barrel and the lens holder may include: a threaded connection method, in which threads are respectively formed on the outer surface of the lens barrel and the inner surface of the lens holder, and then the threads formed on the outer surface of the lens barrel and the threads formed on the inner surface of the lens holder are screwed together; and an adhesive bonding method, in which the lens barrel and the lens holder are bonded to each other by an adhesive.

[0006] When the screw connection method is used, foreign matter may be generated during the assembly process, and the lens barrel may be assembled to be tilted with respect to the image sensor.

[0007] When the adhesive bonding method is used, the adhesive may be over-injected and overflow, the assembly position of the lens barrel may deviate during the curing process of the adhesive, or the lens disposed in the lens barrel may be deformed due to heat for curing the adhesive.

[0008] The above information is presented as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be applicable as prior art with respect to the present disclosure. Summary of the invention

[0009] The purpose of providing this summary is to introduce a selection of inventive concepts in a concise form, and these inventive concepts will be further described in the following detailed description. This summary is not intended to identify the key features or essential features of the subject matter claimed, nor is it intended to help determine the scope of the subject matter claimed.

[0010] In one general aspect, a lens assembly includes: a lens barrel formed of a first material; and a lens holder connected to the lens barrel and formed of a second material, wherein a joining portion where the lens barrel and the lens holder are joined to each other includes a mixed layer in which the first material and the second material are mixed with each other, and wherein the joining portion includes one or more gaps.

[0011] The first material and the second material may each include a plastic material.

[0012] One or more of the first material and the second material may include any one of polycarbonate, polyarylate, polyphthalamide, and liquid crystal polymer.

[0013] One or more of the first material and the second material may include a filler.

[0014] The mixed layer may contain one or more of chloroform, cyclohexanone, tetrahydrofuran, ketone, and benzene.

[0015] The mixed layers may be spaced apart and formed along a circumferential surface of the lens barrel.

[0016] The mixed layer may be continuously formed along the circumferential surface of the lens barrel.

[0017] A plurality of gaps may be irregularly formed in the joining portion.

[0018] The lens barrel and the lens holder may be spaced apart by at least 20 μm in a direction perpendicular to the optical axis direction in a region other than the joining portion.

[0019] The second material may be different from the first material.

[0020] The lens barrel and the lens holder may include irregular concave-convex facing surfaces adjacent to the engaging portion.

[0021] In another general aspect, a camera module includes: a lens barrel formed of a first material; a lens holder connected to the lens barrel and formed of a second material; a housing in which the lens barrel and the lens holder are housed; and a lens driving device including a magnet attached to the lens holder and a coil arranged to face the magnet, wherein the first material and the second material include the same or different plastic materials, wherein a joining portion in which the lens barrel and the lens holder are joined to each other includes a mixed layer in which the first material and the second material are mixed with each other, and wherein the joining portion includes one or more gaps.

[0022] The lens barrel and the lens holder are spaced apart from each other in a direction perpendicular to the optical axis direction in a region other than the engaging portion.

[0023] The camera module may be a mobile electronic device, further comprising: an image sensor configured to convert light incident through the lens barrel into an electrical signal; and a display unit provided on a surface of the mobile electronic device to display an image based on the electrical signal.

[0024] In another general aspect, a mobile electronic device includes: a lens barrel configured to refract light on an image sensor to generate an electrical signal; a lens holder connected to the lens barrel; a joining portion disposed between the lens holder and the lens barrel to join the lens holder to the lens barrel, wherein the joining portion includes a mixed layer of a material of the lens barrel and a material of the lens holder; and a display unit configured to display an image in response to the electrical signal.

[0025] The material of the lens barrel and the material of the lens holder may include the same plastic material or different plastic materials.

[0026] The void may be provided in one or more of the lens barrel adjacent to the engagement portion, the engagement portion, and the lens holder adjacent to the engagement portion.

[0027] Surfaces of the lens barrel and the lens holder that face each other adjacent to the engaging portion may be irregular.

[0028] Other features and aspects will become apparent from the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a perspective view illustrating a camera module according to one or more example embodiments.

[0030] Figure 2 is a schematic exploded perspective view illustrating a camera module according to one or more example embodiments.

[0031] Figure 3 is a perspective view of a lens assembly according to one or more embodiments.

[0032] Figure 4 is a plan view of a lens assembly according to one or more embodiments.

[0033] Figure 5 is along Figure 3 A cross-sectional view taken along line AA'.

[0034] Figure 6 yes Figure 5 An enlarged view of part B.

[0035] Figure 7 is a schematic diagram illustrating a process in which a lens barrel and a lens holder are coupled to each other according to one or more example embodiments.

[0036] Fig. 8A and Figure 8B is a perspective view showing one or more examples of a camera module installed in a mobile electronic device.

[0037] Throughout the drawings and detailed description, the same reference numerals refer to the same elements. For purposes of clarity, illustration, and convenience, the drawings may not be drawn to scale, and the relative sizes, proportions, and depictions of elements in the drawings may be exaggerated. DETAILED DESCRIPTION

[0038] The following detailed description is provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described in this application. However, after understanding the present disclosure, various changes, modifications and equivalences of the methods, devices and / or systems described in this application will be apparent. For example, the order of operations described in this application is merely an example, and except for operations that must occur in a specific order, it is not limited to the order set forth in this application, but can be made obvious changes after understanding the present disclosure. In addition, for greater clarity and brevity, the description of features well known in the art may be omitted.

[0039] The features described in this application may be implemented in different forms and should not be construed as being limited to the examples described in this application. More specifically, the examples described in this application are provided only to illustrate some of the many possible ways of implementing the methods, devices and / or systems described in this application, which will be apparent after understanding this disclosure. Hereinafter, although embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the examples are not limited thereto.

[0040] Throughout the specification, when an element such as a layer, a region, or a substrate is described as being “on,” “connected to,” or “coupled to” another element, the element may be directly “on,” “connected to,” or “coupled to” the other element, or one or more other elements may be present between the element and the other element. Conversely, when an element is described as being “directly on,” “directly connected to,” or “directly coupled to” another element, there may be no other elements between the element and the other element.

[0041] As used in this application, the term "and / or" includes any one of the associated listed items and any combination of any two or more items; similarly, "at least one of..." includes any one of the associated listed items and any combination of any two or more items.

[0042] Although the terms "first", "second" and "third" may be used in this application to describe various members, components, regions, layers or parts, these members, components, regions, layers or parts are not limited by these terms. More specifically, these terms are only used to distinguish one member, component, region, layer or part from another member, component, region, layer or part. Therefore, without departing from the teachings of the examples described in this application, the first member, first component, first region, first layer or first part mentioned in these examples may also be referred to as the second member, second component, second region, second layer or second part.

[0043] Spatially relative terms such as "above", "higher", "below", and "lower" may be used in this application for descriptive convenience to describe the relationship of one element relative to another element as shown in the accompanying drawings. In addition to covering the orientations depicted in the accompanying drawings, these spatially relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the accompanying drawings is flipped, an element described as being "above" or "higher" relative to another element will be "below" or "lower" relative to the other element. Therefore, depending on the spatial orientation of the device, the term "above" covers both orientations of "above" and "below". The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative terms used in this application should be interpreted accordingly.

[0044] The terms used in this application are only used to describe various examples and are not used to limit the present disclosure. Unless the context clearly indicates otherwise, the articles "a", "an" and "the" are intended to also include plural forms. The words "include", "comprise" and "have" indicate the presence of the features, numbers, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, operations, components, elements and / or combinations thereof.

[0045] Variations in the shapes shown in the drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described in the present application are not limited to the specific shapes shown in the drawings, but include variations in shapes that occur during manufacturing.

[0046] Features of the examples described in this application may be combined in various ways that will be apparent after understanding the present disclosure. In addition, although the examples described in this application have various configurations, other configurations that will be apparent after understanding the present disclosure are also possible.

[0047] It should be noted that in the present application, the use of the word “may” with respect to an example, for example, regarding what an example may include or implement, means that there is at least one example in which such feature is included or implemented, and all examples are not limited thereto.

[0048] One aspect of the present disclosure may provide a lens assembly, a camera module, and a mobile electronic device, in which a lens barrel and a lens holder may be effectively coupled to each other without using an ultraviolet (UV) adhesive or a thermosetting adhesive.

[0049] The lens assembly according to the examples described in the present application may be provided in a camera module installed in a mobile electronic device.

[0050] In the examples described in this application, the mobile electronic device may refer to a portable electronic device, such as a mobile communication terminal, a smart phone, a tablet computer, etc.

[0051] Figure 1 is a perspective view showing a camera module according to one or more examples described in the present application, and Figure 2 is a schematic exploded perspective view showing a camera module according to one or more examples described in the present application.

[0052] See also Figure 1 and Figure 2 According to the example, the camera module 1000 may include a lens assembly 200, a lens driving device that moves the lens assembly 200, an image sensor module 700 that converts light incident to the image sensor module 700 through the lens assembly 200 into an electrical signal, a housing 120 that accommodates the lens assembly 200 and the lens driving device therein, and a casing 110.

[0053] The lens assembly 200 may include a lens barrel 210 in which a lens is mounted and a lens holder 320 coupled to the lens barrel 210 .

[0054] The lens barrel 210 may be in a hollow cylindrical shape so that a plurality of lenses for imaging an object may be housed therein. The plurality of lenses may be arranged in the lens barrel 210 along an optical axis.

[0055] The number of the plurality of lenses arranged in the lens barrel 210 may depend on the design of the lens barrel 210 , and the respective lenses may have optical characteristics such as the same or different refractive indices.

[0056] The lens driving device may move the lens assembly 200 .

[0057] For example, the lens driving device can perform focusing by moving the lens assembly 200 in the optical axis (Z-axis) direction, and perform image stabilization by moving the lens assembly 200 in a direction (X-axis direction and / or Y-axis direction) perpendicular to the optical axis (Z-axis) when capturing an image.

[0058] The lens driving device may include a focus unit 400 that performs focusing and an image stabilization unit 500 that performs image stabilization.

[0059] The image sensor module 700 may convert light passing through a lens into an electrical signal.

[0060] For example, the image sensor module 700 may include an image sensor 710 and a printed circuit board 720 connected to the image sensor 710 , and may further include an infrared filter.

[0061] An infrared filter can be used to block light in the infrared region of the light passing through the lens.

[0062] The image sensor 710 may convert light passing through the lens into an electrical signal. For example, the image sensor 710 may be a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS).

[0063] The electrical signal converted by the image sensor 710 can be transmitted through the mobile electronic device 1 ( Fig. 8A and Figure 8B ) of the display unit 20( Fig. 8A ) is output as an image.

[0064] The image sensor 710 may be fixed to the printed circuit board 720 , and may be electrically connected to the printed circuit board 720 through wire bonding.

[0065] The lens assembly 200 and the lens driving device may be accommodated in the housing 120 .

[0066] For example, the housing 120 may be in a shape with the top and bottom opened, and the lens assembly 200 and the lens driving device may be accommodated in an inner space of the housing 120 .

[0067] The image sensor module 700 may be disposed on the bottom of the housing 120 .

[0068] In addition, the substrate 600 may be disposed on the side surface of the housing 120 and provide a driving signal for the focus unit 400 and the image stabilization unit 500. The substrate 600 may be a single substrate 600 surrounding the side surface of the housing 120.

[0069] As described below, an opening can be set in the side surface of the shell 120 so that the driving coil 430 and the first position detection unit 470 of the focusing unit 400 and the first driving coil 510b, the second driving coil 520b and the second position detection unit of the image stabilization unit 500 can be inserted into the opening.

[0070] The housing 110 may be coupled to the case 120 and may serve to protect internal components of the camera module 1000 .

[0071] In addition, the housing 110 may be used to shield electromagnetic waves.

[0072] For example, the housing 110 may shield electromagnetic waves generated from the camera module so that the electromagnetic waves do not affect other electronic components in the mobile electronic device.

[0073] In addition, since a plurality of electronic components and a camera module are installed in the mobile electronic device, the housing 110 may also shield electromagnetic waves generated from these electronic components so that the electromagnetic waves do not affect the camera module.

[0074] The housing 110 may be formed of metal and grounded to a ground pad provided on the printed circuit board 720 to shield electromagnetic waves.

[0075] See also Figure 2 , describing the focus unit 400 of the lens driving device of the camera module 1000 according to the example disclosed in this application.

[0076] The lens assembly 200 may be moved by a lens driving device to focus on an object.

[0077] For example, the focus unit 400 in this example may move the lens assembly 200 in the optical axis (Z-axis) direction.

[0078] The focus unit 400 may include a carrier 300 in which the lens assembly 200 is accommodated, and a magnet 410 and a driving coil 430 that generate a driving force to move the lens assembly 200 and the carrier 300 in the optical axis (Z-axis) direction.

[0079] The magnet 410 may be mounted on the carrier 300. For example, the magnet 410 may be mounted on one surface of the carrier 300.

[0080] The driving coil 430 may be a copper foil pattern stacked and buried in the substrate 600. The substrate 600 may be mounted on a side surface of the housing 120 such that the magnet 410 and the driving coil 430 face each other in a direction perpendicular to the optical axis (Z axis).

[0081] The magnet 410 may be a moving member that is mounted on the carrier 300 and moves in the optical axis (Z-axis) direction together with the carrier 300 , and the driving coil 430 may be a fixed member that is fixed to the housing 120 .

[0082] When power is applied to the driving coil 430 , the carrier 300 may move in the optical axis (Z-axis) direction by electromagnetic interaction between the magnet 410 and the driving coil 430 .

[0083] like Figure 2 As shown, the frame 310 and the lens holder 320 are accommodated in the carrier 300, and the lens barrel 210 is installed in the lens holder 320; therefore, when the carrier 300 moves, the frame 310, the lens holder 320 and the lens barrel 210 can also move in the optical axis (Z axis) direction.

[0084] The rolling members B1 may be disposed between the carrier 300 and the housing 120 to reduce friction between the carrier 300 and the housing 120 when the carrier 300 moves. Each of the rolling members B1 may be in a spherical shape.

[0085] The rolling members B1 may be provided at both sides of the magnet 410 .

[0086] The first yoke 450 may be disposed to face the magnet 410 in a direction perpendicular to the optical axis (Z axis). For example, the first yoke 450 may be mounted on the outer surface of the substrate 600 (i.e., the other surface of the substrate 600 opposite to the one surface of the substrate 600 in which the drive coil 430 is embedded). Therefore, the first yoke 450 may be disposed to face the magnet 410, and the drive coil 430 is interposed between the first yoke 450 and the magnet 410.

[0087] An attractive force may act between the first yoke 450 and the magnet 410 in a direction perpendicular to the optical axis (Z axis).

[0088] Therefore, the rolling member B1 may be maintained in contact with the carrier 300 and the housing 120 by the attractive force between the first yoke 450 and the magnet 410 .

[0089] In addition, the first yoke 450 may serve to focus the magnetic force of the magnet 410. Therefore, it is possible to prevent the magnetic flux from leaking.

[0090] For example, the first yoke 450 and the magnet 410 may form a magnetic circuit.

[0091] Meanwhile, the second yoke 420 may be disposed between the magnet 410 and the carrier 300. The second yoke 420 may serve to focus the magnetic force of the magnet 410. Therefore, leakage of magnetic flux may be prevented.

[0092] For example, the second yoke 420 and the magnet 410 may form a magnetic circuit.

[0093] In the present disclosure, a closed-loop control method may be used to detect and feedback the position of the lens assembly 200 .

[0094] Therefore, a first position detection unit 470 may be provided to perform closed-loop control. The first position detection unit 470 may include a plurality of coils 470a and 470b and a control unit electrically connected to the plurality of coils 470a and 470b. The plurality of coils 470a and 470b may also be a copper foil pattern similar to the drive coil 430 stacked and buried in the substrate 600. Figure 2 The exemplary embodiment in FIG. 4 shows two coils 470 a and 470 b ; however, three or more coils are also possible.

[0095] The first position detecting unit 470 may be disposed to face the sensing yoke 460 disposed adjacent to the magnet 410. The sensing yoke 460 may be mounted on one surface of the carrier 300, and may be a conductor or a magnetic body.

[0096] The first position detection unit 470 may be disposed to face the sensing yoke 460 in a direction perpendicular to the optical axis (Z axis). In addition, the first position detection unit 470 may be disposed adjacent to the driving coil 430.

[0097] When the carrier 300 moves in the optical axis (Z axis) direction, the sensing yoke 460 mounted on the carrier 300 may also move in the optical axis (Z axis) direction. Therefore, the inductance of the first position detection unit 470 may be changed. The control unit may receive the inductance value from the first position detection unit 470 to detect the position of the lens barrel 210 (in the optical axis (Z axis) direction).

[0098] Therefore, the position of the sensing yoke 460 can be detected according to the change of the inductance of the first position detection unit 470. The sensing yoke 460 can be mounted on the carrier 300; the lens barrel 210 can be accommodated in the carrier 300; and the carrier 300 can move in the optical axis (Z axis) direction together with the lens barrel 210. Therefore, the position of the lens barrel 210 (in the optical axis (Z axis) direction) can be finally detected according to the change of the inductance of the first position detection unit 470.

[0099] The first position detection unit 470 may include a plurality of coils arranged in the optical axis (Z axis) direction. For example, the first position detection unit 470 may include two coils 470a and 470b arranged in the optical axis (Z axis) direction.

[0100] When the sensing yoke 460 moves in the optical axis (Z axis) direction, the position of the lens barrel 210 in the optical axis (Z axis) direction may be more accurately detected using a difference between signals generated from the two coils 470a and 470b of the first position detecting unit 470.

[0101] The inductance value of the two coils 470a and 470b depends not only on the relative position difference between the two coils 470a and 470b and the sensing yoke 460, but also on the temperature change in the surrounding environment and the like.

[0102] However, in this example, the accurate position of the lens barrel 210 can be detected by removing factors caused by temperature changes and the like in the surrounding environment.

[0103] For example, when the sensing yoke 460 moves, the inductances of the two coils 470a and 470b may have increasing and decreasing directions different from each other. That is, when the inductance of one coil 470a increases, the inductance of the other coil 470b may decrease.

[0104] Therefore, when subtraction is performed between the inductance values ​​of the two coils 470a and 470b, factors caused by temperature changes in the surrounding environment can be removed, and accordingly, the position of the lens barrel 210 in the optical axis (Z-axis) direction can be accurately detected.

[0105] In this example, the first position detecting unit 470 is described as facing the sensing yoke 460. However, the first position detecting unit 470 may also be provided to face the magnet 410 without separately providing the sensing yoke 460.

[0106] See also Figure 2 , describing the image stabilization unit 500 of the lens driving device of the camera module 1000 according to the example disclosed in the present application.

[0107] The image stabilization unit 500 may be used to correct image blur or video shake that occurs due to factors such as hand shake of a user when capturing an image or recording a video.

[0108] For example, when shaking occurs by hand shaking of a user or the like during capturing an image, the image stabilization unit 500 may compensate for the shaking by allowing the lens barrel 210 to be relatively shifted to correspond to the shaking.

[0109] For example, the image stabilization unit 500 may move the lens barrel 210 in a direction perpendicular to the optical axis (Z axis) to correct shaking.

[0110] The image stabilization unit 500 may include a guide member that guides movement of the lens barrel 210 , and a plurality of magnets and a plurality of coils that generate a driving force to move the guide member in a direction perpendicular to the optical axis (Z axis).

[0111] The plurality of magnets may include a first magnet 510 a and a second magnet 520 a ; and the plurality of coils may include a first driving coil 510 b and a second driving coil 520 b .

[0112] The guide member may include a frame 310 and a lens holder 320. The frame 310 and the lens holder 320 may be sequentially inserted into the carrier 300 in the optical axis (Z axis) direction and serve to guide the movement of the lens barrel 210.

[0113] The frame 310 and the lens holder 320 may each have a space into which the lens barrel 210 may be inserted. The lens barrel 210 may be inserted into and fixed to the lens holder 320.

[0114] In this example, even if a guide member that guides the movement of the lens barrel 210 is used when correcting shake, the overall height of the camera module (the height in the optical axis (Z-axis) direction) may not be increased.

[0115] For example, when viewed from the optical axis (Z axis) direction, the frame 310 of the guide member may be formed in a shape with both sides of a square removed. Therefore, when viewed from the optical axis (Z axis) direction, the frame 310 may be Or a “∟” shape.

[0116] The first magnet 510a and the second magnet 520a may be respectively disposed on both opening sides of the frame 310. Therefore, the first magnet 510a and the second magnet 520a may be disposed without being affected by the position of the frame 310, so that the overall height of the camera module may not be increased.

[0117] The frame 310 and the lens holder 320 may be moved relative to the carrier 300 in a direction perpendicular to the optical axis (Z axis) by a driving force generated by a plurality of magnets and a plurality of coils.

[0118] The first magnet 510a and the first drive coil 510b can generate a driving force in the direction of the first axis (X axis) perpendicular to the optical axis (Z axis); and the second magnet 520a and the second drive coil 520b can generate a driving force in the direction of the second axis (Y axis) perpendicular to the first axis (X axis). That is, multiple magnets and multiple coils can generate driving forces in respective opposite directions.

[0119] Here, the second axis (Y axis) refers to an axis perpendicular to both the optical axis (Z axis) and the first axis (X axis).

[0120] The plurality of magnets may be disposed orthogonally to each other on a plane perpendicular to the optical axis (Z axis); and the plurality of coils may also be disposed orthogonally to each other on a plane perpendicular to the optical axis (Z axis).

[0121] The first magnet 510a and the second magnet 520a may be mounted on the lens holder 320. For example, the first magnet 510a and the second magnet 520a may be respectively mounted on the side surface of the lens holder 320. The side surface of the lens holder 320 may include a first surface and a second surface perpendicular to each other, and the first magnet 510a and the second magnet 520a may be respectively disposed on the first surface and the second surface of the lens holder 320.

[0122] The first drive coil 510b and the second drive coil 520b may be copper foil patterns stacked and buried in the substrate 600. The substrate 600 may be mounted on a side surface of the housing 120 such that the first magnet 510a and the first drive coil 510b face each other in a direction (e.g., an X-axis direction) perpendicular to the optical axis (Z-axis), and the second magnet 520a and the second drive coil 520b face each other in another direction (e.g., a Y-axis direction) perpendicular to the optical axis (Z-axis).

[0123] The first magnet 510 a and the second magnet 520 a may be moving members that move in a direction perpendicular to the optical axis (Z axis) together with the lens holder 320 ; and the first drive coil 510 b and the second drive coil 520 b may be fixed members fixed to the housing 120 .

[0124] In this example, a plurality of ball members may be provided to support the frame 310 and the lens holder 320 of the image stabilization unit 500. The plurality of ball members may be used to guide the movement of the frame 310, the lens holder 320, and the lens barrel 210 during the image stabilization process. In addition, the plurality of ball members may also be used to maintain the respective intervals between the carrier 300, the frame 310, and the lens holder 320.

[0125] The plurality of ball members may include a first ball member B2 and a second ball member B3.

[0126] The first ball member B2 can guide the movement of the frame 310, the lens holder 320 and the lens barrel 210 in the first axis (X axis) direction; and the second ball member B3 can guide the movement of the lens holder 320 and the lens barrel 210 in the second axis (Y axis) direction.

[0127] For example, when a driving force is generated in the first axis (X axis) direction, the first ball member B2 can move in a rolling motion in the first axis (X axis) direction. Therefore, the first ball member B2 can guide the movement of the frame 310, the lens holder 320 and the lens barrel 210 in the first axis (X axis) direction.

[0128] In addition, when a driving force is generated in the second axis (Y axis) direction, the second ball member B3 can move in a rolling motion in the second axis (Y axis) direction. Therefore, the second ball member B3 can guide the movement of the lens holder 320 and the lens barrel 210 in the second axis (Y axis) direction.

[0129] The first ball member B2 may include a plurality of ball members disposed between the carrier 300 and the frame 310 ; and the second ball member B3 may include a plurality of ball members disposed between the frame 310 and the lens holder 320 .

[0130] The first guide groove portion 301 in which the first ball member B2 is accommodated may be formed on surfaces of the carrier 300 and the frame 310 facing each other in the optical axis (Z axis) direction, respectively. The first guide groove portion 301 may include a plurality of guide grooves corresponding to a plurality of ball members (ie, the first ball members B2).

[0131] The first ball member B2 may be received in the first guide groove portion 301 and assembled between the carrier 300 and the frame 310 .

[0132] When the first ball member B2 is accommodated in the first guide groove portion 301, the first ball member B2 can be restricted from moving in the optical axis (Z axis) direction and the second axis (Y axis) direction, and the first ball member B2 can be allowed to move only in the first axis (X axis) direction. For example, the first ball member B2 can be allowed to move only in the first axis (X axis) direction in a rolling motion.

[0133] To this end, each plane of the plurality of guide grooves of the first guide groove portion 301 may have a rectangular shape that is long in the first axis (X axis) direction.

[0134] The second guide groove portion 311 in which the second ball member B3 is accommodated may be formed on the surfaces of the frame 310 and the lens holder 320 facing each other in the optical axis (Z axis) direction, respectively. The second guide groove portion 311 may include a plurality of guide grooves corresponding to the plurality of ball members (ie, the second ball members B3).

[0135] The second ball member B3 may be received in the second guide groove portion 311 and assembled between the frame 310 and the lens holder 320 .

[0136] When the second ball member B3 is accommodated in the second guide groove portion 311, the second ball member B3 can be restricted from moving in the optical axis (Z axis) direction and the first axis (X axis) direction, and the second ball member B3 can be allowed to move only in the second axis (Y axis) direction. For example, the second ball member B3 can move in a rolling motion only in the second axis (Y axis) direction.

[0137] To this end, each plane of the plurality of guide grooves of the second guide groove part 311 may have a rectangular shape that is long in the second axis (Y axis) direction.

[0138] Meanwhile, in the example described in the present application, the third ball member B4 may be disposed between the carrier 300 and the lens holder 320 to support the movement of the lens holder 320 .

[0139] The third ball member B4 can support the lens holder 320 so as to move in the first axis (X axis) direction and the second axis (Y axis) direction.

[0140] For example, when a driving force is generated in the first axis (X axis) direction, the third ball member B4 may move in a rolling motion in the first axis (X axis) direction.

[0141] In addition, when a driving force is generated in the second axis (Y axis) direction, the third ball member B4 can move in a rolling motion in the second axis (Y axis) direction.

[0142] At the same time, the second ball member B3 and the third ball member B4 may contact and support the lens holder 320 .

[0143] The receiving groove 302 in which the third ball member B4 is accommodated may be respectively formed in one or more surfaces of the carrier 300 and the lens holder 320 facing each other in the optical axis (Z-axis) direction.

[0144] The third ball member B4 may be received in the receiving groove 302 and assembled between the carrier 300 and the lens holder 320 .

[0145] When the third ball member B4 is accommodated in the receiving groove 302, the movement of the third ball member B4 in the optical axis (Z axis) direction can be restricted, and the third ball member B4 can be allowed to move in a rolling motion in the first axis (X axis) direction and the second axis (Y axis) direction.

[0146] To this end, the receiving grooves 302 may each have a plane formed in a circular shape. Therefore, the receiving groove 302, the first guide groove portion 301, and the second guide groove portion 311 may have shapes different from each other.

[0147] The first ball member B2 can move in a rolling motion in the first axis (X axis) direction; the second ball member B3 can move in a rolling motion in the second axis (Y axis) direction; and the third ball member B4 can move in a rolling motion in the first axis (X axis) direction and the second axis (Y axis) direction.

[0148] Therefore, a plurality of ball members supporting the image stabilization unit 500 according to the present example may have different degrees of freedom from each other.

[0149] Here, the degree of freedom refers to the number of independent variables required to represent the motion state of an object in a three-dimensional (3D) coordinate system.

[0150] Generally, 6 can be the degrees of freedom of an object in a 3D coordinate system. The movement of an object can be represented by an orthogonal coordinate system with three directions and a rotational coordinate system with three directions.

[0151] For example, an object in a 3D coordinate system may move along corresponding axes (X-axis, Y-axis, and Z-axis) in a translational motion, and may move relative to corresponding axes (X-axis, Y-axis, and Z-axis) in a rotational motion.

[0152] In this example, the degrees of freedom refer to the number of independent variables required to represent the movement of the first ball member B2, the second ball member B3, and the third ball member B4 when the image stabilization unit 500 moves by generating a driving force in a direction perpendicular to the optical axis (Z axis) by applying power to the image stabilization unit 500.

[0153] For example, by generating a driving force in a direction perpendicular to the optical axis (Z axis), the third ball member B4 can move in a rolling motion along two axes (the first axis (X axis) and the second axis (Y axis)), and the first ball member B2 and the second ball member B3 can move in a rolling motion along a single axis (the first axis (X axis) or the second axis (Y axis)).

[0154] Therefore, the degree of freedom of the third ball member B4 may be different from the degree of freedom of the first ball member B2 and the second ball member B3.

[0155] When a driving force is generated in the first axis (X axis) direction, the frame 310 , the lens holder 320 , and the lens barrel 210 may move together in the first axis (X axis) direction.

[0156] Here, the first ball member B2 and the third ball member B4 can move in a rolling motion along the first axis (X axis). In this case, the movement of the second ball member B3 can be restricted.

[0157] In addition, when a driving force is generated in the second axis (Y axis) direction, the lens holder 320 and the lens barrel 210 may move in the second axis (Y axis) direction.

[0158] Here, the second ball member B3 and the third ball member B4 can move in a rolling motion along the second axis (Y axis). In this case, the movement of the first ball member B2 can be restricted.

[0159] In the example described in the present application, a plurality of yokes 510 c and 520 c may be provided so that the image stabilization unit 500 and the first to third ball members B2 , B3 , and B4 are kept in contact with each other.

[0160] The plurality of yokes 510 c and 520 c may be fixed to the carrier 300 , and may be disposed to face the first magnet 510 a and the second magnet 520 a , respectively, in the optical axis (Z-axis) direction.

[0161] Therefore, an attractive force can be generated in the optical axis (Z-axis) direction between the plurality of yokes 510 c and 520 c and the first magnet 510 a and the second magnet 520 a , respectively.

[0162] The image stabilization unit 500 can be pressed toward the multiple yokes 510c and 520c by the attraction between the multiple yokes 510c and 520c and the first and second magnets 510a and 520a, so that the frame 310 and the lens holder 320 of the image stabilization unit 500 can remain in contact with the first to third ball members B2, B3 and B4.

[0163] The plurality of yokes 510c and 520c may be formed of a material that can generate an attractive force between the plurality of yokes 510c and 520c and the first and second magnets 510a and 520a. For example, the plurality of yokes 510c and 520c may be formed of a magnetic material.

[0164] In this example, a plurality of yokes 510c and 520c may be provided so that the frame 310 and the lens holder 320 may be kept in contact with the first to third ball members B2, B3, and B4. A stopper 330 may be provided to prevent the first to third ball members B2, B3, and B4, the frame 310, and the lens holder 320 from being separated to the outside of the carrier 300 by external impact or the like.

[0165] The stopper 330 may be coupled to the carrier 300 to cover at least a portion of an upper surface of the lens holder 320 .

[0166] In this example, a closed-loop control approach may be used to detect and provide feedback on the position of the lens barrel 210 during the image stabilization process.

[0167] Therefore, a second position detection unit may be provided to perform closed-loop control. The second position detection unit may be configured to detect the position of the lens barrel 210 in the first axis (X axis) direction and the second axis (Y axis) direction.

[0168] The second position detection unit may include a plurality of coils and a control unit electrically connected to the plurality of coils. The control unit may receive inductance values ​​from the plurality of coils to detect the position of the lens barrel 210 in the first axis (X axis) direction and the second axis (Y axis) direction.

[0169] Similar to the first driving coil 510 b , the plurality of coils may also be copper foil patterns stacked and buried in the substrate 600 .

[0170] The plurality of coils may be disposed on both sides of the first driving coil 510b or the second driving coil 520b. For example, when the plurality of coils is two coils, each coil may be disposed on both sides of the first driving coil 510b or the second driving coil 520b.

[0171] Hereinafter, for convenience of explanation, the plurality of coils will be described as being disposed on both sides of the first driving coil 510 b , but it is also possible to dispose the plurality of coils on both sides of the second driving coil 520 b .

[0172] The first magnet 510a may be arranged to face the first driving coil 510b in the first axis (X axis) direction. In addition, the first magnet 510a may be arranged in such a manner that one side of the first magnet 510a may partially face one of the plurality of coils of the second position detection unit, and the other side of the first magnet 510a may partially face another of the plurality of coils of the second position detection unit.

[0173] Here, the 1-1th sensing coil 511 a refers to a coil partially facing one side of the first magnet 510 a , and the 1-2nd sensing coil 511 b refers to a coil partially facing the other side of the first magnet 510 a .

[0174] When the first magnet 510 a moves in the first axis (X axis) direction and / or the second axis (Y axis) direction, the inductance of the plurality of sensing coils 511 a and 511 b of the second position detection unit may change.

[0175] Therefore, the position of the first magnet 510a can be detected according to the change of the inductance of the plurality of sensing coils 511a and 511b. The first magnet 510a is mounted on the lens holder 320; the lens barrel 210 is mounted on the lens holder 320; and the lens holder 320 moves together with the lens barrel 210 in the first axis (X axis) direction and / or the second axis (Y axis) direction. Therefore, the position of the lens barrel 210 (in the first axis (X axis) direction and / or the second axis (Y axis) direction) can be finally detected according to the change of the inductance of the plurality of sensing coils 511a and 511b of the second position detection unit.

[0176] Hereinafter, a method of detecting the position of the lens barrel 210 in the first axis (X-axis) direction is described.

[0177] When the lens barrel 210 moves in the first axis (X axis) direction, the inductances of the 1-1st sensing coil 511a and the 1-2nd sensing coil 511b may have the same increasing direction and decreasing direction.

[0178] Therefore, the second position detection unit of the camera module 1000 according to the example described in the present application can be configured to accurately detect the position of the lens barrel 210 in the first axis (X-axis) direction by using any one of the inductance values ​​of the 1-1 sensing coil 511a and the 1-2 sensing coil 511b, depending on the movement of the lens barrel 210; or by using a value obtained by adding the two inductance values.

[0179] Hereinafter, a method of detecting the position of the lens barrel 210 in the second axis (Y-axis) direction is described.

[0180] When the lens barrel 210 moves in the second axis (Y-axis) direction, the inductances of the 1-1th sensing coil 511a and the 1-2nd sensing coil 511b may have increasing and decreasing directions different from each other.

[0181] Therefore, the second position detection unit of the camera module 1000 according to the example described in the present application can be configured to accurately detect the position of the lens barrel 210 in the second axis (Y axis) direction by performing subtraction between the inductance values ​​of the 1-1 sensing coil 511a and the 1-2 sensing coil 511b.

[0182] See also Figure 2 , the first ball member B2 may be accommodated in the first guide groove portion 301 and assembled between the carrier 300 and the frame 310. The second ball member B3 may be accommodated in the second guide groove portion 311 and assembled between the frame 310 and the lens holder 320. The third ball member B4 may be accommodated in the receiving groove 302 and assembled between the carrier 300 and the lens holder 320.

[0183] Figure 3 is a perspective view of a lens assembly according to one or more examples described in the present application, and Figure 4 is a plan view of a lens assembly according to one or more examples described in this application.

[0184] Figure 5 is along Figure 3 A cross-sectional view taken along line AA' of FIG. Figure 6 yes Figure 5 An enlarged view of part B.

[0185] in addition, Figure 7 is a schematic diagram showing a process in which a lens barrel and a lens holder are joined to each other.

[0186] Generally, methods of coupling the lens barrel and the lens holder may include a threading method and an adhesive bonding method.

[0187] In the screw connection method, threads are formed on an outer surface of a lens barrel and an inner surface of a lens holder, respectively, and then the threads formed on the outer surface of the lens barrel and the threads formed on the inner surface of the lens holder are tightened to each other.

[0188] However, when the threaded connection method is used, foreign matter may be generated during the assembly process by friction between the lens barrel and the lens holder. In addition, assembly tilt may occur during the assembly process. Assembly tilt refers to a state in which the verticality of the lens relative to the image sensor deviates from the designed verticality when the lens barrel and the lens holder are assembled to each other. In recent years, with the miniaturization of camera modules, such a small error may affect image quality.

[0189] In the adhesive bonding method, instead of forming threads in the lens barrel and the lens holder, the lens barrel may be inserted into the lens holder and coated and cured with an adhesive so that the lens barrel is fixed to the lens holder.

[0190] However, when the adhesive bonding method is used, it is difficult to control the amount of adhesive applied, and the position of the lens barrel may deviate during the curing process of the adhesive. In particular, the lens disposed in the lens barrel may be deformed by the heat used to cure the adhesive.

[0191] In the examples described in the present application, the lens barrel 210 and the lens holder 320 may be coupled to each other using a coupling method other than the screw connection method and the adhesive bonding method.

[0192] An insertion hole may be formed at the center of the lens holder 320, and the lens barrel 210 may be inserted into the insertion hole. The insertion hole may be formed to have a diameter slightly larger than the outer diameter of the lens barrel 210. For example, the outer surface of the lens barrel 210 may be spaced apart from the inner surface of the lens holder 320 by a distance "d".

[0193] The bonding portion 230 may be formed between the lens barrel 210 and the lens holder 320, and the lens barrel 210 and the lens holder 320 may be directly bonded to each other through the bonding portion 230. Here, the bonding portion 230 may be formed by melting a portion of the lens barrel 210 and a portion of the lens holder 320. Therefore, the lens barrel 210 may be bonded to the lens holder 320 without separately using an adhesive.

[0194] At least a portion of the outer surface of the lens barrel 210 and at least a portion of the inner surface of the lens holder 320 may be melted and then joined to each other. That is, at least a portion of the surfaces of the lens barrel 210 and the lens holder 320 facing each other may be melted and then joined to each other to form the joining portion 230.

[0195] An irregular concavo-convex structure may be formed on portions of surfaces of the lens barrel 210 and the lens holder 320 that face each other, and these portions are adjacent to the engaging portion 230. That is, an interface between the lens barrel 210 and the engaging portion 230 and an interface between the lens holder 320 and the engaging portion 230 may include an irregular concavo-convex structure.

[0196] A space of at least 20 μm may be provided between the outer surface of the lens barrel 210 and the inner surface of the lens holder 320 facing each other in a direction perpendicular to the optical axis direction. That is, a space of at least 20 μm may be provided in a region excluding the coupling portion 230 between the lens barrel 210 and the lens holder 320 in a direction perpendicular to the optical axis.

[0197] The lens barrel 210 may be formed of a first material, the lens holder 320 may be formed of a second material, and the first material and the second material may include plastic materials, respectively.

[0198] One or more of the first material and the second material may include any one of polycarbonate, polyarylate, polyphthalamide, and liquid crystal polymer.

[0199] Here, the first material and the second material may include the same or different plastic materials.

[0200] One or more of the first material and the second material may include a filler.

[0201] The filler is a material used to improve the physical properties of the first material and the second material.

[0202] One or more voids 231 may be formed in the coupling portion 230, in which the lens barrel 210 and the lens holder 320 are coupled to each other. A plurality of voids 231 may be irregularly formed.

[0203] The gap 231 may also be formed in a region other than the coupling portion 230 , for example, in a portion of the lens barrel 210 and / or a portion of the lens holder 320 .

[0204] During the bonding process, a volatile material 800 may be used to form the bonding portion 230. The volatile material 800 may be used to cause melting of at least a portion of the lens barrel 210 and at least a portion of the lens holder 320.

[0205] For example, the volatile substance 800 may be one or more of chloroform, cyclohexanone, tetrahydrofuran, ketone, and benzene.

[0206] like Figure 7As shown in , when the volatile material 800 is applied between the lens barrel 210 and the lens holder 320 , the lens barrel 210 and the lens holder 320 may be temporarily melted, and the melted materials may be mixed with each other to form the coupling portion 230 .

[0207] Therefore, the bonding portion 230 may include a mixed layer in which the first material of the lens barrel 210 and the second material of the lens holder 320 are mixed with each other.

[0208] After melting the surfaces of the lens barrel 210 and the lens holder 320 , the volatile material 800 may be completely volatilized from the joining portion 230 or partially remain in the joining portion 230 .

[0209] The volatile material 800 may be spaced apart and applied along the circumferential surface of the lens barrel 210, or may be continuously applied along the circumferential surface of the lens barrel 210. The circumferential surface of the lens barrel 210 refers to the outer circumference of the lens barrel 210, for example.

[0210] Therefore, the coupling portion 230 may be spaced apart along the circumferential surface of the lens barrel 210 and formed along the circumferential surface of the lens barrel 210 , or may be continuously formed along the circumferential surface of the lens barrel 210 .

[0211] See also Fig. 8A and Figure 8B , the camera module 1000 according to the examples described in the present application may be installed in the mobile electronic device 1 and further include a display unit 20, wherein the camera module 1000 is installed together with the display unit 20 as a front camera of the mobile electronic device 1, or is installed on one side of the mobile electronic device 1 other than the side having the display unit 20 as a rear camera. As described in various examples, the electrical signal converted by the image sensor 710 of the camera module 1000 may be output as an image via the display unit 20 of the mobile electronic device 1.

[0212] As described above, in the lens assembly, the camera module, and the mobile electronic device according to the examples described in the present application, the lens barrel and the lens holder can be effectively coupled to each other without using an ultraviolet (UV) adhesive or a thermosetting adhesive.

[0213] Although specific examples have been shown and described above, it will be apparent after understanding the present disclosure that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described in this application are understood in a descriptive sense only, and not for limiting purposes. The description of the features or aspects in each example should be considered to be applicable to similar features or aspects in other examples. If the described techniques are performed in a different order, and / or if the components in the described system, architecture, device or circuit are replaced or supplemented in a different manner and / or by other components or their equivalents, appropriate results can still be achieved. Therefore, the scope of the present disclosure is not limited by specific embodiments, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents should be understood to be included in the present disclosure.

Claims

1. A camera module, comprising: a lens barrel formed of a first material; a lens holder coupled to an outer surface of the lens barrel and formed of a second material; a lens driving device comprising a magnet attached to the lens holder and a coil arranged to face the magnet; as well as a position detection unit facing a sensing yoke disposed adjacent to the magnet and including a plurality of coils and a control unit electrically connected to the plurality of coils, The outer surface of the lens barrel and the inner surface of the lens holder are spaced apart from each other by a predetermined distance in a direction perpendicular to the optical axis to form a receiving space extending in the optical axis direction. wherein a joining portion where the outer surface of the lens barrel and the inner surface of the lens holder are joined to each other is formed in a portion of the accommodation space, the joining portion includes a mixed layer in which the first material and the second material are mixed with each other, and Wherein, the joining portion includes one or more gaps.

2. The lens assembly according to claim 1, wherein: The first material and the second material each include a plastic material.

3. The lens assembly according to claim 2, wherein: One or more of the first material and the second material include any one of polycarbonate, polyarylate, polyphthalamide, and liquid crystal polymer.

4. The lens assembly according to claim 3, wherein: One or more of the first material and the second material includes a filler.

5. The lens assembly according to claim 1, wherein: The mixed layer contains one or more of chloroform, cyclohexanone, tetrahydrofuran, ketone and benzene.

6. The lens assembly according to claim 1, wherein: The mixed layers are spaced apart and formed along a circumferential surface of the lens barrel.

7. The lens assembly according to claim 1, wherein: The mixed layer is continuously formed along a circumferential surface of the lens barrel.

8. The lens assembly according to claim 1, wherein: A plurality of voids are irregularly formed in the engaging portion.

9. The lens assembly according to claim 1, wherein: The lens barrel and the lens holder are spaced apart by at least 20 μm in a direction perpendicular to the optical axis direction in a region other than the engaging portion.

10. The lens assembly according to claim 1, wherein: The second material is the same as or different from the first material.

11. The lens assembly according to claim 1, wherein: The lens barrel and the lens holder include irregular concave-convex facing surfaces adjacent to the engaging portion.

12. A mobile electronic device, comprising: The camera module according to any one of claims 1 to 11; an image sensor configured to convert light incident through the lens barrel into an electrical signal; as well as The display unit is arranged on the surface of the mobile electronic device to display an image based on the electrical signal.

13. A mobile electronic device, comprising: a lens barrel configured to refract light on the image sensor to generate an electrical signal; a lens holder coupled to an outer surface of the lens barrel and spaced apart from the outer surface of the lens barrel by a predetermined distance in a direction perpendicular to the optical axis direction to form an accommodation space extending in the optical axis direction; a lens driving device comprising a magnet attached to the lens holder and a coil arranged to face the magnet; a position detection unit facing a sensing yoke disposed adjacent to the magnet and including a plurality of coils and a control unit electrically connected to the plurality of coils; a joining portion disposed in a portion of the accommodation space to join the lens holder to the lens barrel, wherein the joining portion includes a mixed layer of a material of the lens barrel and a material of the lens holder; and a display unit configured to display an image in response to the electrical signal, Wherein, the joining portion includes one or more gaps.

14. The mobile electronic device according to claim 13, wherein: The material of the lens barrel and the material of the lens holder include the same plastic material or different plastic materials.

15. The mobile electronic device according to claim 13, wherein: Surfaces of the lens barrel and the lens holder facing each other adjacent to the engaging portion are irregular.

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