JP2008026504A - Lens drive module, camera module and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens drive module capable of securely moving a lens hold frame holding a lens unit and attaining the miniturization, and to provide a camera module and an electronic device having it. <P>SOLUTION: The lens drive module includes: the lens hold frame holding the lens unit in it and supported so as to be freely movable reciprocally in the direction of the optical axis of the lens unit; and a moving means that moves the lens hold frame reciprocally. The moving means includes: a thin plate-like slide member 19 connected to the lens hold frame 8 at one end so as to be swinguable, and supported so as to be rotatable within a plane around a shaft 23 perpendicular to the direction of an optical axis; and a drive device which comprises a flat plate-like magnet 21 and a voice coil disposed opposite to the magnet 21 and which is disposed at the other end of the slide member 19. Rotating the slide member 19 around the shaft 23 by the drive device moves the lens hold frame 8 reciprocally in the direction of the optical axis. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens driving module including a lens unit that is moved for focus adjustment and the like, and in particular, a lens driving module suitable for mounting on a small electronic device such as a mobile phone and a personal digital assistant (PDA), and The present invention relates to a camera module and an electronic device provided with the same.

  In recent years, a camera module having a small lens driving module has been mounted on a small electronic device such as a cellular phone. Solid-state imaging devices such as CCD image sensors and CMOS image sensors used in these camera modules are increasing in pixel count, and higher quality images are required. For this reason, functions such as autofocus, optical zoom, and macro photography have been added to the lens driving module constituting the camera module.

For example, as a camera module (imaging device) having an autofocus function, there is a configuration in which an optical component is moved by a stepping motor (see, for example, Patent Document 1). Thus, in the configuration using the stepping motor, the camera module can be downsized to some extent. However, with the miniaturization of electronic devices, there is a demand for further miniaturization of the lens driving module and the camera module including the lens driving module. Further, if the lens drive module or the like is further downsized, there is a possibility that sufficient torque for moving the optical component such as the lens unit cannot be obtained.
JP 2005-148197 A

  The present invention has been made in view of such circumstances, and includes a lens drive module, a camera module, and a lens drive module that can reliably move the lens holding frame that holds the lens unit and can be downsized. It is an object to provide an electronic device to be used.

  According to a first aspect of the present invention for solving the above-described problem, a lens unit including one or a plurality of lenses, and the lens unit is held on the base member so as to reciprocate in the optical axis direction of the lens unit. A lens holding module, and a moving means for reciprocating the lens holding frame, the moving means being pivotally connected to the lens holding frame on one end side. And a thin plate-like slide member supported so as to be rotatable in an in-plane direction around an axis orthogonal to the optical axis direction, a flat plate magnet, and a flat plate disposed opposite to the magnet And a drive device provided on the other end side of the slide member, and the drive device rotates the slide member around the axis. It is, Te is the lens holding frame by utilizing this principle to the lens driving module, wherein the reciprocating direction of the optical axis.

  In the first aspect, the drive device can be downsized to greatly reduce the installation area. Thereby, size reduction of a lens drive module can be achieved.

According to a second aspect of the present invention, either the voice coil or the magnet constituting the driving device is fixed to the surface near the other end of the slide member, and the other is fixed to the base member. Also in the second aspect of the lens driving module according to the first aspect, the driving device is reduced in size and the installation area is reduced.

  According to a third aspect of the present invention, either the voice coil or the magnet constituting the driving device is held by a movable member supported so as to be reciprocally movable in the optical axis direction, and the other is the base member. The lens driving module according to the first aspect is characterized in that the sliding member is swingably connected to the movable member on the other end side.

  In the third aspect, the voice coil and magnet constituting the drive device can be relatively enlarged to improve the torque, and the lens drive module is not enlarged.

  According to a fourth aspect of the present invention, there is provided the lens drive module according to the third aspect, wherein the slide member and the movable member are arranged in an intersecting direction.

  In the fourth aspect, the lens driving module can be more reliably downsized.

  The fifth aspect of the present invention further includes a cover member provided so as to cover the slide member and the movable member and having a rectangular outer shape in cross section, and the slide member is one of the cover members. The lens driving according to the fourth aspect, wherein the lens driving device is arranged to face the side surface, and the driving device is arranged to face the other inner side surface adjacent to the one inner side surface of the cover member. In the module.

  In the fifth aspect, it is possible to reliably reduce the size while protecting the lens driving module accommodated in the cover member.

  According to a sixth aspect of the present invention, there is provided an engaging projection in which a connecting portion in which the lens holding frame and the slide member are connected protrudes from the outer periphery of the lens holding frame in the thickness direction of the slide member. The lens driving module according to any one of the first to fifth aspects, wherein the lens driving module includes an engagement recess provided on the slide member and slidably engaged with the engagement protrusion. .

  In the sixth aspect, the lens holding frame can be reliably moved in conjunction with the rotation of the slide member.

  In a seventh aspect of the present invention, the slide member is made of a conductive material, and is provided on a circuit board that is fixed to the base member as the slide member rotates in the vicinity of the one end and the other end. Any one of the first to sixth aspects, further comprising a position detecting unit that detects a position of the lens unit from a conduction state between each contact part and the contacted part, as well as a contact part that contacts the contacted part. It exists in the lens drive module of the aspect.

  In the seventh aspect, the position of the lens holding frame can be detected relatively easily and reliably.

  An eighth aspect of the present invention is the lens driving module according to any one of the first to seventh aspects, wherein the lens holding frame is always urged toward the base member by the urging member.

  In the eighth aspect, the lens holding frame is urged by the urging member, so that the movement of the lens holding frame is stabilized and the lens can be moved to a desired position.

  According to a ninth aspect of the present invention, there is provided the lens drive module according to any one of the first to eighth aspects, and an image pickup device disposed to face the lens unit of the lens drive module. Located in the camera module.

  In the ninth aspect, it is possible to realize a camera module that can reliably move the lens to a desired position and is miniaturized.

  According to a tenth aspect of the present invention, there is provided an electronic apparatus comprising the camera module according to the ninth aspect.

  In the tenth aspect, the camera-equipped electronic device can be downsized.

  In the present invention, since the lens holding frame is moved by the slide member, the lens holding frame can be moved reliably and the lens driving module can be downsized. In addition, it is possible to reduce the size of the camera module including the lens driving module and the electronic device including the camera module.

  Hereinafter, the present invention will be described based on embodiments.

(Embodiment 1)
1 is a schematic plan view showing the internal structure of a camera module including a lens driving module according to Embodiment 1 of the present invention, and FIG. 2 is a view taken along the line AA ′ of FIG. FIG. 2 is a sectional view taken along line BB ′ of FIG.

  As shown in the figure, a camera module 1 according to the present embodiment is provided on an image sensor 3 such as a CCD image sensor or a CMOS image sensor provided on a circuit board 2 and in a region facing the image sensor 3. And a cover 5 in which the image pickup device 3 and the lens driving module 4 are housed. The lens driving module 4 includes a lens unit 7 composed of a plurality of lenses 6, a lens holding frame 8 that holds the lens unit 7, and a moving unit 9 that moves the lens holding frame 8.

  The base member 10 constituting the lens driving module 4 has a penetrating portion 11 for taking in light, and a circuit board 2 having a substantially rectangular shape provided with the imaging element 3 is fixed to one surface side thereof. Yes. For example, in the present embodiment, on the circuit board 2, an image sensor cover 13 having an opening 12 is joined to a region facing the image sensor 3, and the image sensor cover 13 is a region facing the penetrating part 11. The image pickup device 3 is fixed to the base member 10 so that the image pickup device 3 is positioned on the base member 10. Note that the opening 12 of the image sensor cover 13 is covered with an optical filter 14 bonded to the inner surface of the image sensor cover 13 in this embodiment.

  The cover 5 in which the lens driving module 4 and the like are housed is formed to have a rectangular cross section, in this embodiment, a square, and is fixed to the circuit board 2 on which the image sensor 3 is provided. In addition, in order to operate | move the drive device mentioned later favorably, it is preferable that this cover 5 is formed with the electromagnetic shielding material. For example, in the present embodiment, the cover 5 is made of an iron-based metal material and also functions as an electromagnetic shield.

  A lens holding frame 8 that holds the lens unit 7 is disposed in a region of the base member 10 opposite to the imaging element 3 so as to face the penetrating portion 11 of the base member 10. That is, the lens holding frame 8 is disposed at a position facing the image sensor 3. The lens holding frame 8 is supported by the base member 10 so as to be capable of reciprocating along the optical axis direction (vertical direction in FIG. 2) of the lens 6. For example, in this embodiment, two guide shafts 15A and 15B are erected on the base member 10 with the penetrating portion 11 interposed therebetween, and the lens holding frame 8 is supported by these guide shafts 15A and 15B. ing.

  Of these guide shafts 15A, 15B, one guide shaft 15A induces movement of the lens holding frame 8 in the optical axis direction, and the other guide shaft 15B rotates the lens holding frame 8 in the plane direction. It is regulated. For example, in the present embodiment, a guide sleeve 17 having a guide hole 16 is provided on the outer peripheral surface of the lens holding frame 8, and a guide shaft 15 </ b> A is inserted through the guide hole 16. Further, the outer peripheral surface of the lens holding frame 8 has two protrusions 18 protruding to the opposite side of the guide sleeve 17, and the guide shaft 15 </ b> B is engaged between the protrusions 18.

  Further, the moving means 9 for moving the lens holding frame 8 supported by the guide shafts 15 </ b> A and 15 </ b> B in this way is provided close to the lens holding frame 8. The moving means 9 according to the present embodiment is swingably connected to the lens holding frame 8 on one end side in the longitudinal direction, and rotates in an in-plane direction around an axis perpendicular to the optical axis direction of the lens 6. A thin plate-like slide member 19 that is movably supported, a magnet 21, and a plate-like voice coil 20 disposed opposite to the magnet 21, and a drive provided on the other end side of the slide member 19. Device 22.

  The slide member 19 according to the present embodiment is disposed along one inner surface of the cover 5 adjacent to the lens holding frame 8. The slide member 19 has a slide shaft 23 protruding from the surface thereof, and is fixed to the base member 10 so that the slide shaft 23 is in a direction perpendicular to the optical axis direction. For example, in the present embodiment, the slide shaft 23 is slidably supported on the support plate 24 provided integrally with the base member 10, and the slide member 19 can be rotated within a predetermined range around the slide shaft 23. ing.

  Then, one end portion (left end portion in FIG. 2) side in the in-plane direction of the slide member 19 is connected to the lens holding frame 8. For example, in the present embodiment, the guide sleeve 17 is provided on the outer periphery of the lens holding frame 8 as described above, and the guide sleeve 17 is provided with the contact pin 25 protruding in the axial direction of the slide shaft 23. Yes. On the other hand, one end of the slide member 19 is provided with an engaging recess 26 that opens outward in the direction inclined with respect to the optical axis direction, that is, in the in-plane direction. The contact pin 25 is slidably engaged with the engagement recess 26 to connect the slide member 19 and the lens holding frame 8. In the present embodiment, the other end portion side of the slide member 19 is formed so that its planar shape is substantially a fan shape. That is, the end surface on the other end side of the slide member 19 is an arc centered on the slide shaft 23.

  The drive device 22 according to the present embodiment is provided in the vicinity of the end of the fan-shaped slide member 19. The drive device 22 is a so-called voice coil motor that includes a voice coil 20 and a magnet 21 that is a permanent magnet disposed opposite to the voice coil 20. The magnet 21 constituting the driving device 22 is fixed to the surface near the other end of the slide member 19. Further, the magnet 21 is formed in an arc shape along the end face shape of the slide member 19. On the other hand, the voice coil 20 is held by a holding member 27 fixed to the base member 10 so as to face the magnet 21.

  In addition, since the slide member 19 to which the magnet 21 is fixed is provided close to the cover 5 and the cover 5 is formed of an iron-based metal material, the cover 5 functions as an electromagnetic shield and the yoke of the magnet 21 Also works. In addition, the magnet 21 is preferably polarized to the S pole and the N pole in the optical axis direction, but may not be polarized.

  Then, by supplying electric power (current) to the voice coil 20 constituting the driving device 22 in a predetermined direction, a force directed downward (circuit board 2 side) or upward is applied to the magnet 21 fixed to the slide member 19. The slide member 19 is rotated about the slide shaft 23 by the action. Further, as the slide member 19 rotates, the contact pin 25 provided on the lens holding frame 8 slides within the engagement recess 26 of the slide member 19 so that the lens holding frame 8 moves in the vertical direction (optical axis direction). ) For example, when the other end side of the slide member 19 moves downward, the one end side moves upward, and accordingly, the lens holding frame 8 moves upward. On the other hand, when the other end side of the slide member 19 moves upward, the one end side moves downward, and accordingly, the lens holding frame 8 also moves downward.

  That is, the slide shaft 23 of the slide member 19 is a fulcrum, the portion where the magnet 21 is fixed is the force point, and the portion where the contact pin 25 and the engagement recess 26 engage is the point of action. The generated force is transmitted to the lens holding frame 8 so that the lens holding frame 8 moves along the optical axis direction. For example, in the present embodiment, the lens holding frame 8 is moved by about 0.3 mm along the optical axis direction by such moving means 9.

  The positional relationship between the slide shaft 23 provided in the slide member 19, the engagement recess 26, and the magnet 21, that is, the positional relationship between the fulcrum, the force point, and the action point is not particularly limited. For example, in the present embodiment, The distance from the center of the slide shaft 23 to the engaging recess 26 and the distance from the center of the slide shaft to the center of the magnet 21 are set to a ratio of about 1: 3. The size of the magnet 21 fixed to the slide member 19 is not particularly limited, and may be appropriately determined in consideration of the magnitude of the force acting on the lens holding frame 8, the balance of the slide member 19, and the like. It is desirable to form it relatively large.

  As described above, in the present invention, the moving means 9 for moving the lens holding frame 8 includes the slide member 19 and the driving device 22 composed of the voice coil 20 and the magnet 21, and uses the lever principle. Thus, the lens holding frame 8 is moved. Thereby, the lens holding frame 8 can be reliably moved, and the lens driving module 4 can be significantly reduced in size as compared with a conventional one using a stepping motor or the like. For example, when a stepping motor is used as the moving means 9, a space of at least about 4 mm square is required, and the lens driving module 4 is at least about 12 mm square. On the other hand, the moving means 9 according to the present invention can be installed in a slight space between the lens holding frame 8 and the cover 5. Accordingly, it is possible to realize a very small lens driving module 4 having a size close to the outer diameter of the lens holding frame 8, for example, about 10 mm square. Further, the camera module 1 can be reduced in size as the lens driving module 4 is reduced in size.

  The slide member 19 according to the present embodiment is made of a conductive material such as a metal material, and a projecting portion 28 that projects toward the circuit board 2 is provided near one end of the slide member 19. Yes. The tip of the protruding portion 28 is a contact portion that comes into contact with the first contacted portion 29 provided on the circuit board 2 as the slide member 19 rotates. The projecting portion 28 which is the contact portion contacts the first contacted portion 29 in a state where the slide member 19 is disposed at the reference position at the lower end. On the other hand, the corner portion 30 on the other end side of the slide member 19 is a contact portion whose tip is in contact with the second contacted portion 31 provided on the circuit board 2, similarly to the protruding portion 28. The corner portion 30 which is the contact portion is formed on the second contacted portion 31 when the slide member 19 rotates downward (circuit board 2 side) and the lens holding frame 8 is disposed at the upper reference position. Contact. A position detection unit (not shown) detects the conduction between the protruding portion 28 and the first contacted portion 29 or the conduction between the corner portion 30 and the second contacted portion 31, whereby the lens holding frame 8. The position of can be specified.

  In this way, in conjunction with the movement of the lens holding frame 8, the contact positions of the slide member 19 and the first or second contacted parts 29, 31 are connected to detect the reference position, so that they are independent. The position of the lens unit 7 can be specified without using a member. For this reason, it is possible to reduce the cost of the lens driving module 4 while suppressing an increase in the number of parts.

(Embodiment 2)
4 is a schematic plan view showing an internal structure of a camera module provided with a lens driving module according to Embodiment 2, FIG. 5 is a view taken along the line CC ′ of FIG. 4, and FIG. FIG. 4 is a view taken along the line DD ′ in FIG. In addition, the same code | symbol is attached | subjected to the same member and the overlapping description is abbreviate | omitted.

  This embodiment is an example in which the moving means 9A is composed of a slide member 19A and a drive device 22A connected to the other end side of the slide member 19A. As shown in the figure, the drive device 22A according to the present embodiment is arranged in a direction intersecting with the slide member 19A, in the present embodiment, in an orthogonal direction. In other words, the driving device 22A is disposed so as to face the inner side surface adjacent to the inner side surface of the cover 5 provided with the slide member 19A close thereto.

  The voice coil 20 </ b> A constituting the driving device 22 </ b> A has a length substantially equal to the diameter of the lens holding frame 8 and is held by a holding member 27 </ b> A provided integrally with the base member 10. On the other hand, the magnet 21 </ b> A is held by a movable holding member 32 supported so as to be reciprocally movable in the optical axis direction of the lens unit 7. The movable holding member 32 is slidably supported by a guide shaft 15B that regulates the rotation of the lens holding frame 8 in the vicinity of the end opposite to the slide member 19A. Further, a contact pin 33 protruding toward the slide member 19A is provided at the end of the movable holding member 32 on the slide member 19A side, and is connected to the slide member 19A by this contact pin 33. In other words, an engagement recess 34 is formed at the other end of the slide member 19 </ b> A to engage a contact pin 33 provided on the movable holding member 32, and the contact pin 33 can slide in the engagement recess 34. Is engaged.

  The slide member 19A according to the present embodiment is different from the slide member 19 of the first embodiment in that the slide member 19A is formed with a substantially uniform width along the length direction, but rotates around the slide shaft 23. There is no change in the supported structure. Further, the slide member 19A is provided with a first protrusion 28A that protrudes toward the circuit board 2 in the vicinity of one end, and in the present embodiment, also toward the circuit board 2 in the vicinity of the other end. A protruding second protruding portion 28B is provided. The second protruding portion 28B functions in the same manner as the corner portion 30 described in the first embodiment.

  In such a lens driving module 4A according to the present embodiment, when power is supplied to the voice coil 20A, the movable holding member 32 holding the magnet 21A moves upward or downward along the optical axis direction. For example, when the movable holding member 32 moves downward, a force that moves downward via the contact pin 33 acts on the other end of the slide member 19A, and the movable holding member 32 moves upward. In this case, a force that moves upward via the contact pin 33 acts on the other end of the slide member 19A. Then, the slide member 19A is rotated about the slide shaft 23 by the force received from the movable holding member 32, so that the lens holding frame 8 moves along the optical axis direction as described in the first embodiment. .

  In the present embodiment, for example, a bearing member 35 such as an oil-impregnated bearing is fixed to the guide sleeve 17 of the lens holding frame 8, and the lens holding frame 8 is supported on the guide shaft 15A via the bearing member 35. Has been. Thereby, the lens holding frame 8 can be moved more smoothly by the moving means 9A.

  In the present embodiment, the lens holding frame 8 is always urged downward (circuit board 2 side) by an urging member 36 formed of a compression coil spring or the like fitted into the guide shaft 15A. Thereby, the lens holding frame 8 is stably held at a predetermined position. As described above, since the lens holding frame 8 is moved only to the two reference positions of the upper end and the lower end, the reference position on the upper end side of the lens holding frame 8 is provided when the urging member 36 is provided. The movement of the lens holding frame 8 may be moved to the reference position on the lower end side by using the force of the biasing member 36.

  In the configuration of the present embodiment described above, the drive device 22A is provided separately from the slide member 19A, so that the areas of the voice coil 20A and the magnet 21A constituting the drive device 22A can be increased. Therefore, the torque generated by the driving device 22A can be greatly improved, and the lens holding frame 8 can be moved more reliably. Further, since the voice coil 20A and the magnet 21A constituting the driving device 22A can be installed in a very narrow space between the lens holding frame 8 and the cover 5 even if the area is relatively large, the lens driving module 4A. Does not substantially increase in size.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, this invention is not limited to these embodiment. For example, in the above-described embodiment, the example in which the voice coil constituting the driving device is fixed to the base member and the magnet is provided so as to be movable has been described. However, the present invention is not limited to this, and the magnet is fixed to the base member. Then, the voice coil may be provided so as to be movable. In the above-described embodiment, the lens holding frame is configured to move only to the two reference positions of the upper end and the lower end. Of course, the lens holding frame may be configured to be moved to a desired position and held. it can.

  Further, the above-described camera module 1 according to the present invention is suitable for mounting on a small electronic device such as a mobile phone shown in FIG. A cellular phone 100 shown in FIG. 7 has a configuration in which a first housing 101 and a second housing 102 are connected via a hinge 103 and can be folded by the hinge 103. The camera module 1 is built in the first housing 101 so that the lens unit 7 is exposed to the outside when the cellular phone 100 is folded. Note that the electronic device on which the camera module 1 is mounted can be mounted not only on such a mobile phone but also on any electronic device such as an electronic personal digital assistant (PDA).

3 is a plan view of the camera module according to Embodiment 1. FIG. It is an AA 'arrow line view of the camera module which concerns on Embodiment 1. FIG. FIG. 4 is a cross-sectional view of the camera module according to Embodiment 1 taken along the line BB ′. 6 is a plan view of a camera module according to Embodiment 2. FIG. It is CC 'arrow line view of the camera module which concerns on Embodiment 2. FIG. FIG. 6 is a DD ′ arrow view of the camera module according to the second embodiment. It is a perspective view which shows an example of the electronic device carrying a camera module.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera module 2 Circuit board 3 Image pick-up element 4 Lens drive module 5 Cover 6 Lens 7 Lens unit 8 Lens holding frame 9 Moving means 10 Base member 15A, 15B Guide shaft 17 Guide sleeve 19 Slide member 20 Voice coil 21 Magnet 22 Drive device 23 Slide shaft 24 Support plate 25 Contact pin 26 Engaging recess 27 Holding member 28 Protruding portion 29 Contacted portion 30 Corner portion 31 Contacted portion 32 Movable holding member 33 Contact pin 34 Engaging recess 35 Bearing member 36 Energizing member

Claims (10)

A lens unit composed of one or a plurality of lenses, a lens holding frame that is held on the base member so as to be reciprocally movable in the optical axis direction of the lens unit, and the lens holding frame. A lens driving module comprising a moving means for reciprocating movement,
The moving means is connected to the lens holding frame on one end side so as to be swingable, and is supported in such a manner as to be rotatable in an in-plane direction around an axis orthogonal to the optical axis direction. Comprising a slide member, a plate-shaped magnet and a voice coil arranged opposite to the magnet, and a drive device provided on the other end side of the slide member;
A lens driving module characterized in that the lens holding frame is reciprocated in the optical axis direction using the lever principle by rotating the slide member about the axis by the driving device.   One of the voice coil and the magnet constituting the driving device is fixed to a surface in the vicinity of the other end of the slide member, and the other is fixed to the base member. Item 4. The lens driving module according to Item 1.   Either the voice coil or the magnet constituting the driving device is held by a movable member supported so as to be capable of reciprocating in the optical axis direction, the other is fixed to the base member, and the slide member is The lens driving module according to claim 1, wherein the lens driving module is swingably connected to the movable member on the other end side.   The lens driving module according to claim 3, wherein the slide member and the movable member are arranged in an intersecting direction.   A cover member provided so as to cover the slide member and the movable member and having a rectangular outer shape in cross section; and the slide member is disposed to face one inner surface of the cover member. 5. The lens driving module according to claim 4, wherein the driving device is disposed to face another inner side surface adjacent to the one inner side surface of the cover member.   A connecting portion in which the lens holding frame and the slide member are connected is provided on the outer periphery of the lens holding frame in the thickness direction of the slide member, and on the slide member. The lens driving module according to claim 1, wherein the engaging protrusion is configured by an engaging recess that is slidably engaged.   The slide member is made of a conductive material, and a contact portion that contacts a contacted portion provided on a circuit board fixed to the base member as the slide member rotates in the vicinity of the one end portion and the other end portion. The lens driving module according to claim 1, further comprising position detection means for detecting a position of the lens unit from a conductive state between each contact portion and the contacted portion.   The lens driving module according to claim 1, wherein the lens holding frame is always urged toward the base member by an urging member.   9. A camera module comprising: the lens driving module according to claim 1; and an image pickup device disposed to face the lens unit of the lens driving module.   An electronic apparatus comprising the camera module according to claim 9.

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