Camera module having multi-directional motion carrier unit

Abstract

The present invention relates to a camera module having a multi-directional motion carrier unit. According to the present invention, an OIS carrier and an AF carrier are integrated into a carrier unit, and a suspension spring is provided to elastically support the carrier unit at a predetermined height from the bottom surface of a housing and to simultaneously perform an OIS function. Since the camera module having the multi-directional motion carrier unit of the present invention has the OIS carrier and the AF carrier integrated into one carrier unit, the internal structure is simplified and accordingly the number of components is reduced, and thus the camera module is slim. In addition, hardly any portion is subject to friction, and thus precision of operation is not deteriorated by abrasion, even after the camera module is used for a long time.

Description

Camera module with multidirectional motion carrier unit

[0001] The present invention relates to a camera module mounted on a portable electronic device, and more specifically, to a camera module having a multi-directional motion carrier unit in which an OIS carrier and an AF carrier are integrated into one, thereby having a small number of parts, a simple structure, and a slim structure.

[0002] Cameras in recently released smartphones and other mobile devices are incorporating a variety of cutting-edge technologies. These include autofocusing, which automatically focuses more quickly, and image stabilization.

[0003] Image stabilization is a function that helps to obtain a relatively good image even when the mobile device shakes due to shaking hands when taking a picture. Electronic and optical types are known.

[0004] Electronic image stabilization technology is a technology that improves captured images through processing using software, etc., and optical image stabilization (OIS) is a technology that prevents shaking from being reflected in the image of the subject generated on the image sensor by physically correcting the position of the lens or image element caused by hand shake, etc.

[0005] However, while optical image stabilization technology can be easily applied to digital cameras with relatively ample internal space, its application is limited in devices with limited internal space, such as smartphones. This creates a demand for smaller image stabilization devices.

[0006] As a technology that serves as the background for inventions related to camera modules, domestic patent registration No. 10-2560194 (OIS camera module) has been disclosed.

[0007] The disclosed camera module comprises a base, a Z carrier, an XY carrier, an X-direction driving magnet and a Y-direction driving magnet, and a plurality of bearing balls.

[0008] The above Z carrier is arranged to overlap the base so as to be movable in the optical axis direction with respect to the base. The above Z carrier has an X-direction return induction yoke and a Y-direction return induction yoke embedded inside the Z carrier and made of a ferromagnetic material.

[0009] The above XY carrier is arranged to overlap the Z carrier so as to be movable in the X and Y directions orthogonal to each other while being orthogonal to the optical axis for the Z carrier.

[0010] The above X-direction driving magnet and Y-direction driving magnet are installed on the XY carrier and form a magnetic field that induces an electromagnetic force that moves the XY carrier in the X and Y directions.

[0011] A plurality of bearing balls are interposed between the Z carrier and the XY carrier. The plurality of bearing balls includes a plurality of X-direction bearing balls that overlap and contact the X-direction driving magnet and a plurality of Y-direction bearing balls that overlap and contact the Y-direction driving magnet.

[0012] When the XY carrier moves relative to the Z carrier, a return force is applied to the XY carrier so that the X-direction driving magnet is aligned with the X-direction return induction yoke in the optical axis direction and the Y-direction driving magnet is aligned with the Y-direction return induction yoke in the optical axis direction.

[0013] Meanwhile, conventional camera modules often use multiple support balls to support the OIS carrier. The support balls are components that are interposed between the AF carrier and the OIS carrier and support the OIS carrier.

[0014] However, this type of camera module can have its support ball detached during use. For example, if the mobile device is dropped, the support ball can pop out. Without the support ball, the OIS carrier cannot function properly. Furthermore, a metal insert plate is required to support the support ball. Thus, camera modules utilizing the support ball have a large number of components, limiting their ability to reduce unit costs. Furthermore, they are thick.

[0015] The present invention was created to solve the above problems, and the purpose of the present invention is to provide a camera module having a multi-directional motion carrier unit that has a simple internal structure, a slim structure with few components, and almost no frictional parts, so that even if used for a long time, there is no decrease in operating precision due to wear.

[0016] As a solution to the problem of achieving the above purpose, the camera module having a multi-directional motion carrier unit of the present invention includes a housing, a carrier unit, a suspension spring, and a driving unit.

[0017] The housing is open at the top and has a light passage in the center of the bottom surface.

[0018] The carrier unit includes a unit body and a plurality of magnetic parts. The unit body is movably accommodated within the housing and has a lens module at its center. The plurality of magnetic parts surround the unit body.

[0019] The suspension spring elastically supports the carrier unit at a certain height from the bottom surface of the housing.

[0020] The driving unit raises and lowers the carrier unit within the housing in the direction of the optical axis, and moves the carrier unit when the carrier unit is eccentric so that the central axis of the lens module is aligned with the center of the optical path.

[0021] In addition, the housing takes the form of a square frame, and on the side walls located on opposite sides with the optical passage between them, AF coil receiving holes are formed, a Y-OIS coil receiving hole is formed on one of the remaining side walls, and an X-OIS coil receiving hole is provided on the other side wall.

[0022] Additionally, the driving unit may include a circuit board, an AF coil, a pair of Y-OIS coils, an X-OIS coil, and a sensor.

[0023] The circuit board surrounds the housing and receives power from the outside. The AF coil is connected to the circuit board and accommodated in each AF coil accommodation hole. A pair of Y-OIS coils is connected to the circuit board and accommodated in parallel in the Y-OIS coil accommodation holes. The X-OIS coil is connected to the circuit board and accommodated in the X-OIS coil accommodation holes. The sensor detects the movement of the carrier unit.

[0024] In addition, the magnet section may include an AF magnet, a Y magnet of Hansing, and an X magnet. The AF magnets correspond to the AF coils, respectively. A pair of Y magnets correspond to the Y-OIS coil. The X magnet corresponds to the X-OIS coil.

[0025] In addition, the above suspension spring may be provided with a cover frame, an elastic supporter, and an anti-slip plate. The cover frame has an integral structure and is fixed to the upper surface of the unit body. The elastic supporter is integrally formed with the cover frame and outputs elastic force. The anti-slip plate is integrally formed with the end of the elastic supporter and is fixed to the housing.

[0026] In addition, the above suspension spring is formed by pressing and bending a polyimide film having a certain thickness.

[0027] In addition, a number of internal fixing protrusions are formed on the upper surface of the unit body, external fixing protrusions corresponding to the internal fixing protrusions are provided on the housing, and a fixing groove for fixing the cover frame is formed to maintain the floating state of the carrier unit by combining with each internal fixing protrusion.

[0028] Additionally, a catch head that catches the upper surface of the cover frame is further formed on the upper part of the internal fixing protrusion.

[0029] The camera module having the multi-directional motion carrier unit of the present invention, which is formed as described above, has a simple internal structure and is slim with fewer components because the OIS carrier and the AF carrier are integrated into one carrier unit.

[0030] Additionally, since there are almost no friction parts, there is no decrease in operating precision due to wear even if used for a long time.

[0031] FIG. 1 is a perspective view of a camera module having a multi-directional motion carrier unit according to one embodiment of the present invention.

[0032] Figure 2 is an exploded perspective view of the camera module shown in Figure 1.

[0033] Figure 3 is a plan view for explaining the operation method of the carrier unit of Figure 1.

[0034] Fig. 4 is a drawing showing the mounting structure of the suspension spring of Fig. 1.

[0035] Figure 5 is a cross-sectional view taken along line AA of Figure 4.

[0036] Fig. 6 is a drawing showing a modified example of the suspension spring and internal fixing protrusion of Fig. 4.

[0037] Hereinafter, one embodiment according to the present invention will be described in more detail with reference to the attached drawings.

[0038] Basically, the camera module according to the present embodiment has a structure in which the conventional OIS carrier and AF carrier are integrated. In other words, the OIS carrier and AF carrier, which were previously separate components that operated individually, are implemented as a single body. By configuring it this way, components such as rails, insert plates, and support balls that support the OIS carrier and AF carrier are omitted, simplifying the structure of the camera module and making it thinner.

[0039] FIG. 1 is a perspective view of a camera module having a multi-directional motion carrier unit according to one embodiment of the present invention, and FIG. 2 is an exploded perspective view of the camera module illustrated in FIG. 1. In addition, FIG. 3 is a plan view for explaining the operating method of the carrier unit of FIG. 1, and FIG. 4 is a drawing showing the mounting structure of the suspend spring of FIG. 1, and FIG. 5 is a cross-sectional view taken along line AA of FIG. 4.

[0040] As shown in FIGS. 1 to 5, the camera module (10) according to the present embodiment is configured to include a housing (20), a driving unit (30), a carrier unit (40), a suspension spring (50), a lens module (60), and a shield can (70).

[0041] The housing (20) is a square frame case that is open at the top and has a light passage (21k) provided in the center of the bottom surface (21b). A carrier unit (40), a suspension spring (50), and a lens module (60) are built into the housing (20).

[0042] Additionally, an AF coil receiving hole (21f), a Y-OIS coil receiving hole (21c), and an X-OIS coil receiving hole (21d) are formed on the four side walls of the housing (20).

[0043] The AF coil receiving hole (21f) is a hole formed in the side wall opposite the optical path (21k), and receives the AF coil (33) described later. In addition, the Y-OIS coil receiving hole (21c) is a passage formed in one side wall of the remaining side walls, and the X-OIS coil receiving hole (21d) is a passage formed in the other side wall. A Y-OIS coil (32a) is placed in the Y-OIS coil receiving hole (21c), and an X-OIS coil (32b) is placed in the X-OIS coil receiving hole (21d).

[0044] And, external fixing protrusions (21h) are provided on the upper surface of the four corners of the housing (20). The external fixing protrusions (21h) are protrusions corresponding to the internal fixing protrusions (41a) described later and are fitted into the protrusion fixing holes (53a) of the suspension spring (50).

[0045] The driving unit (30) has a circuit board (31), an AF coil (33), a Y-OIS coil (32a), an X-OIS coil (32b), and a sensor (35a, 35b).

[0046] The circuit board (31) is a flexible printed circuit board (FPCB) in the form of a band and covers the four sides of the housing (20). In addition, a connection terminal (31a) is provided at one end of the circuit board (31). As illustrated in Fig. 1, the connection terminal (31a) is exposed to the lower portion of the shield can (75) and receives power from the outside.

[0047] The AF coil (33) is a coil that is electrically connected to the circuit board (31) and accommodated in each AF coil accommodation hole (21f). The AF coil (33) is located on the opposite side of the carrier unit (40) and outputs electromagnetic force. The electromagnetic force output from the AF coil (33) raises and lowers the carrier unit (40) through interaction with the AF magnet (45).

[0048] The Y-OIS coil (32a) is connected to the circuit board and is accommodated in parallel in the Y-OIS coil accommodation hole (21c). That is, two Y-OIS coils (32a) are arranged spaced apart on the left and right. Each Y-OIS coil (32a) corresponds one-to-one to a Y magnet (44). The electromagnetic force output from the Y-OIS coil (32a) moves the carrier unit (40) in the Y direction through interaction with the Y magnet (44).

[0049] The X-OIS coil (32b) is a coil located on the opposite side of the Y-OIS coil (32a), is accommodated in the X-OIS coil accommodation hole (21d), and faces the X magnet (43). The electromagnetic force output from the X-OIS coil (32b) moves the carrier unit (40) in the X direction through interaction with the X magnet (43).

[0050] Ultimately, the carrier unit (40) moves in the direction perpendicular to the optical axis while being raised and lowered in the optical axis direction by the action of the driving unit (30).

[0051] The sensor detects the movement of the carrier unit (40) and is composed of a first sensor (35a) and a second sensor (35b). The first sensor (35a) is installed on the inside of one AF coil (33), and the second sensor (35b) is located on the inside of the X-OIS coil (32b). The first sensor (35a) detects the Y-direction movement of the carrier unit (40), and the second sensor (35b) detects the X-direction movement of the carrier unit (40).

[0052] Meanwhile, the carrier unit (40) is an element that is movably accommodated within the accommodation space (21a) of the housing (20). The carrier unit (40) includes a unit body (41) and a plurality of magnetic parts.

[0053] The unit body (41) has a receiving space (41c) in the center. The receiving space (41c) is a space where a lens module (60) is mounted. The lens module (60) forms one body with the unit body (41) and moves together. In addition, a number of internal fixing protrusions (41a) are formed on the upper surface of the unit body (41).

[0054] The internal fixing protrusions (41a) are arranged in pairs of two at the four corners of the unit body (41). The internal fixing protrusions (41a) are arranged at an equilateral angle of 90 degrees with the lens module (60) at the center. The internal fixing protrusions (41a) are protrusions corresponding to the external fixing protrusions (21h).

[0055] The magnet section includes a plurality of permanent magnets surrounding the unit body. The magnet section includes an AF magnet (45), an X magnet (43), and a Y magnet (44).

[0056] The AF magnets (45) are magnets that correspond to the AF coils (33). The AF magnets (45) are located on opposite sides with the lens module (60) in between. In addition, the X magnets (43) correspond to the X-OIS coils (32b), and the Y magnets (44) correspond to the Y-OIS coils (32a). Two Y magnets (44) are arranged in parallel and face the two Y-OIS coils (32a).

[0057] The suspension spring (50) is an elastic member that connects the carrier unit (40) and the housing (20). The suspension spring (50) has two roles. One of them is to float the carrier unit (40) at a certain height from the bottom surface (21b) of the housing, and the other is to position the carrier unit (40) in the center of the housing (20). That is, when the carrier unit (40) is eccentric, it is positioned in the center by applying elastic force. The position of the carrier unit (40) is a position where the central axis of the lens module (60) coincides with the center point of the optical path (21k) of the housing (20).

[0058] The suspension spring (50) is formed by pressing and bending a polymer film having a certain thickness, for example, a polyimide film, and has a cover frame (51), an elastic supporter (55), and an anti-slip plate (53).

[0059] The suspension spring (50) has multiple bending portions. Since the suspension spring of the present invention is made of a polymer film such as a polyimide film, pressing and bending processes are performed smoothly, and durability is excellent even after being bent and straightened for a long time. If the suspension spring (50) were made of metal, it would be difficult to form a desired bending shape and durability would be poor. In addition, the polyimide film has sufficient elasticity to position the OIS carrier in the correct position.

[0060] The cover frame (51) has an integral structure and is fixed to the upper surface of the unit body (41). The shape of the cover frame (51) corresponds to the planar shape of the unit body (41).

[0061] In addition, a number of protrusion fixing grooves (51a) are formed in the cover frame (51). The protrusion fixing grooves (51a) are grooves that correspond one-to-one to the internal fixing protrusions (41a). The protrusion fixing grooves (51a) accommodate each internal fixing protrusion (41a) and maintain the floating state of the carrier unit (40).

[0062] The fixing projection groove (51a) is a roughly U-shaped groove that is open toward the outside. The diameter of the inner fixing projection (41a) is larger than the width (w) of the fixing projection groove (51a). Therefore, when the inner fixing projection (41a) is inserted into each fixing projection groove (51a), a frictional force is generated between the inner surface of the fixing projection groove (51a) and the outer surface of the inner fixing projection (41a), and the inner fixing projection (41a) is prevented from falling downward due to the frictional force. The diameter of the inner fixing projection (41a) may be 1.1 to 1.2 times the width of the fixing projection groove (51a).

[0063] The elastic supporter (55) is an elastic member that forms an integral part at the four corners of the cover frame (51) and outputs elastic force. The elastic supporter (55) has a roughly U-shape and elastically deforms according to the movement of the carrier unit (40). That is, when the carrier unit (40) is raised or lowered in the optical axis direction or moves laterally, it elastically deforms and then returns to its original state.

[0064] The above-mentioned elastic supporter (55) is a wire-shaped member whose ends are integrally formed with the cover frame (51) and the anti-slip plate (53). The above-mentioned elastic supporter (55) is positioned lower than the plane including the cover frame (51) and the anti-slip plate (53). In other words, it protrudes downward between the cover frame (51) and the anti-slip plate (53).

[0065] In this case, a corner groove (49) having a concave shape may be formed at the four corners of the carrier unit (40) so as to form a supporter receiving groove (S) that receives the elastic supporter (55) between the housing (20).

[0066] The above supporter receiving groove (S) is filled with a damper material so that it can come into contact with the elastic supporter (55). The damper material may include a viscoelastic material. In the present embodiment, the viscoelastic material may include a gel, grease, etc., and its viscosity may be adjusted through UV or heat. The damper material can more quickly absorb the vibration energy of the carrier unit, thereby quickly restoring the carrier unit to its original position.

[0067] In the process of moving the carrier unit (40), the elastic supporter (55) must not come into contact with the side of the supporter receiving groove (S), so the supporter receiving groove (S) can be formed in an area wider than the area in which the elastic supporter (55) can move.

[0068] That is, the elastic supporter (55) is elastically deformed according to the movement of the carrier unit (40), and when the carrier unit (40) is raised or lowered in the optical axis direction or moved laterally, it is elastically deformed and then restored to its original state.

[0069] The anti-slip plate (53) is integrally formed with the end of each elastic supporter (55) and is mounted on the external fixing projection (21h) of the housing. For this purpose, the anti-slip plate (53) is provided with a projection fixing hole (53a). When the external fixing projection (21h) is inserted into the projection fixing hole (53a), the anti-slip plate (53) is coupled to the housing (20).

[0070] Ultimately, since the anti-slip plate (53) is hung on the upper part of the housing (20), the elastic supporter (55) is elastically deformable, and the carrier unit (40) is hung on the cover frame (51), the carrier unit (40) can move while floating from the bottom surface of the housing. That is, as shown in Fig. 5, the carrier unit (40) is maintained in a state of floating by a distance (G) from the bottom surface (41c) of the housing (20).

[0071] Since the carrier unit (40) is maintained in a suspended state by the suspension spring (50), 'supporting parts' such as balls or insert members for supporting the carrier unit are omitted. The balls or insert members are parts that increase the thickness of the camera module (10).

[0072] The shield can (70) is a cover that is detachably connected to the housing (20) and has a passage (71) in the center. The passage (71) is a hole through which the lens module (60) passes. The shield can (70) serves to protect the components housed in the housing (20).

[0073] Fig. 6 is a drawing showing a modified example of the suspension spring (50) and internal fixing protrusion (41a) of Fig. 4.

[0074] As shown, a catch head (41b) is formed at the upper end of the internal fixing protrusion (41a). The catch head (41b) has a diameter that is at least 1.5 times larger than the diameter of the internal fixing protrusion (41a). The catch head (41b) catches on the upper surface of the cover frame (51), thereby allowing the carrier unit (40) to be more stably suspended from the suspension spring (50).

[0075] The operation of the camera module (10) of this embodiment having the above configuration is as follows.

[0076] When a user starts taking a photo using the camera function of a smartphone, the carrier unit (40) moves in the direction of the optical axis according to the distance of the subject of the photo. Of course, when the carrier unit (40) moves in the direction of the optical axis, the elastic supporter (55) also elastically deforms.

[0077] However, when the first and second sensors (35a, 35b) detect shaking of the carrier unit (40) due to the hand shake phenomenon during photography, at that moment, the X-OIS coil (32b) and the Y-OIS coil (32a) output electromagnetic force to return the eccentric carrier unit (40) to its original position. As mentioned above, the original position is the position where the optical axis line coincides with the central axis of the optical path (21k). By repeating the above process, the problem caused by shaking of the camera module (10) is solved.

[0078] Above, the present invention has been described in detail through specific examples, but the present invention is not limited to the above examples, and various modifications are possible by a person of ordinary skill within the scope of the technical idea of ​​the present invention.

[0079] The present invention can be used in portable electronic devices.

Claims

1. A housing that is open to the top and has an optical passage provided in the center of the bottom surface; A unit body that is movably accommodated inside a housing and has a lens module at the center, and a carrier unit that has a plurality of magnets surrounding the unit body; A suspension spring that elastically supports the carrier unit at a certain height from the bottom surface of the housing; A driving unit is included that raises and lowers the carrier unit in the housing in the direction of the optical axis, and moves the carrier unit when the carrier unit is eccentric so that the central axis of the lens module is aligned with the center of the optical path. A camera module having a multidirectional motion carrier unit.

2. In paragraph 1, The above housing takes the form of a square frame, On the side walls located on opposite sides of the optical path, AF coil receiving holes are formed respectively. A Y-OIS coil receiving hole is formed on one of the remaining side walls. The other side wall has an X-OIS coil receiving hole. A camera module having a multidirectional motion carrier unit.

3. In paragraph 2, The above driving part; A circuit board that surrounds the housing and receives power from the outside, An AF coil that is accommodated in each AF coil accommodation hole while connected to the circuit board, A pair of Y-OIS coils connected to the circuit board and accommodated in parallel in the Y-OIS coil accommodation hole, An X-OIS coil connected to the circuit board and accommodated in the X-OIS coil accommodation hole, Including a sensor that detects the movement of the carrier unit, A camera module having a multidirectional motion carrier unit.

4. In paragraph 3, The above magnet part; AF magnets corresponding to each AF coil, A pair of Y magnets corresponding to the Y-OIS coil, Contains an X magnet corresponding to the X-OIS coil, A camera module having a multidirectional motion carrier unit.

5. In paragraph 1, The above suspension spring; A cover frame having an integrated structure and fixed to the upper surface of the unit body, An elastic supporter that is integral to the cover frame and outputs elasticity, Having an anti-slip plate that is integrally formed at the end of the elastic supporter and fixed to the housing, A camera module having a multidirectional motion carrier unit.

6. In paragraph 5, The above elastic supporter is characterized by having a U-shaped shape that protrudes downwards from the cover frame and the anti-slip plate. A camera module having a multidirectional motion carrier unit.

7. In paragraph 6, The carrier unit is characterized in that a corner groove having a concave shape is formed at each of the four corners to form a supporter receiving groove that receives the elastic supporter between the housing and the corner groove. A camera module having a multidirectional motion carrier unit.

8. In paragraph 5, The above suspension spring, It is formed by pressing and bending a polyimide film having a certain thickness. A camera module having a multidirectional motion carrier unit.

9. In paragraph 5, On the upper surface of the above unit body, a number of internal fixing protrusions are formed, The housing is provided with an external fixing projection corresponding to an internal fixing projection, In the cover frame, A protrusion fixing groove is formed to maintain the floating state of the carrier unit by combining with each internal fixing protrusion. A camera module having a multidirectional motion carrier unit.

10. In paragraph 9, At the upper part of the above internal fixing protrusion, A catch head is further formed on the upper surface of the cover frame, A camera module having a multidirectional motion carrier unit.

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