JP2006017818A - Lens unit and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens unit small in the number of components and easy in its assembly work and capable of obtaining a lens arrangement positioned highly precisely, and to provide a manufacturing method therof. <P>SOLUTION: The optical lens unit 1 is constituted so that two or more transparent resin lenses 11, 12 are combined. The optical lens unit 1 comprises effective regions 11a, 12a, first and second transparent resin lenses 11, 12 having edge parts 11b, 12b on the periphery of the resin lenses 11, 12 and an optical path restricting plate 13 which is held between the edge parts 11b, 12b of the first and second transparent resin lenses 11, 12 and shields light between the edge parts. The first transparent resin lens 11 and the optical path restricting plate 13 are welded to each other, and also the second transparent resin lens 12 and the optical path restricting plate 13 are welded to each other. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a combined lens in which a plurality of transparent resin lenses are combined and a method for manufacturing the same.

  Conventionally, resin-made transparent lenses are often used as optical lenses. In particular, a camera lens or the like is often used in combination with a plurality of resin lenses. In general, in such a group lens, each lens is fixed to a lens barrel or fixed to each other so as to hold each lens in a predetermined positional relationship. For this purpose, each resin lens is integrally formed with an area for bonding outside the effective area, and bonding is performed using, for example, an adhesive or an ultrasonic welder.

On the other hand, Patent Documents 1 and 2 disclose a resin material joining method using laser light. In these techniques, a resin member that absorbs laser light and a resin member that transmits laser light are overlapped, and the laser light is irradiated from the side of the resin member that transmits laser light. Then, the laser beam reaches the resin member that absorbs the laser beam and is absorbed, whereby the irradiated portion is heated, and the resin members on both sides are melted and welded together. Patent Document 3 discloses a joining method by irradiating a laser beam with a thin infrared absorbing transparent film sandwiched between transparent resin members.
JP-A-60-214931 Japanese Patent Publication No. 5-42336 JP 2003-181931 A

  However, there are the following problems in the joining in the conventional group lens described above. First, in the bonding method using an adhesive, it takes time to apply and cure the adhesive. In addition, the lens may move due to the shrinkage when the adhesive is cured, and there is a possibility that the positional deviation occurs from a predetermined positional relationship. In that case, there was a problem that the optical performance as a combined lens deteriorated. In addition, in the joining method using an ultrasonic welder, since it is necessary to hold down with a horn, there are restrictions on the shape and size of the lens.

  On the other hand, it is considered that these problems can be avoided by a joining method using laser light. However, in small assembled lenses used for small cameras such as mobile phones, the positioning accuracy of each lens is often required to be high, so it is easy to set the location where laser light is irradiated for welding. It wasn't. In addition, in the technique of laser welding with an infrared absorbing transparent film or the like sandwiched between joining members, there is a problem that the assembly process and the number of parts increase.

  The present invention has been made to solve the problems of the above-described conventional combined lens and the manufacturing method thereof. That is, an object of the present invention is to provide an assembled lens that has a small number of parts, can be easily assembled, and can obtain a highly accurately positioned lens arrangement, and a method for manufacturing the same.

  The combined lens of the present invention made for the purpose of solving this problem is a combined lens formed by combining a plurality of transparent resin lenses, and includes first and second transparent lenses having an effective aperture portion and a plane portion around the effective aperture portion. The resin lens and an optical path regulating plate that is sandwiched between the flat portions of the first and second transparent resin lenses and regulates the optical path. The first transparent resin lens and the optical path regulating plate are also provided in the second The transparent resin lens and the optical path regulating plate are welded.

  According to the combined lens of the present invention, light that enters the flat portion outside the effective aperture portion of the first and second transparent resin lenses is blocked by the optical path regulating plate. That is, this optical path regulating plate is necessary for preventing harmful light from entering the effective aperture of the lens assembly. Here, since the optical path regulating plate is a plate-like member, its thickness dimension can be formed fairly accurately. Therefore, by sandwiching the optical path restricting plate between the flat portions of the first and second transparent resin lenses, the distance between the flat portions is controlled by the thickness of the optical path restricting plate, so that it can be precisely controlled. . Further, since the first transparent resin lens and the optical path regulating plate are welded to each other, and the second transparent resin lens and the optical path regulating plate are welded to each other, the assembled lens of the present invention has the first optical path regulating plate as the center. The transparent resin lens and the second transparent resin lens are fixed to each other. Therefore, it is originally welded to the required optical path control plate, so the number of parts is small and assembly work is easy, and the optical path control plate can be precisely formed, so that a highly accurately positioned lens arrangement can be obtained. .

Further, in the present invention, it is preferable that a recess is formed in one of the transparent resin lens and the optical path regulating plate at the welding position between the first or second transparent resin lens and the optical path regulating plate.
In this way, even if the resin at the welding position with the optical path regulating plate expands somewhat during welding, the expansion is absorbed by the depression. Accordingly, the contact state between the optical path regulating plate and each transparent resin lens is reliably maintained by the portion other than the welded portion, and the lens arrangement can be maintained with high accuracy.

The combined lens of the present invention is a combined lens formed by combining a plurality of transparent resin lenses, the first and second transparent resin lenses having an effective aperture portion and a plane portion around the effective aperture portion, It has an optical path regulating plate that is sandwiched between the second transparent resin lenses and regulates the optical path, and the first transparent resin lens and the second transparent resin lens are welded at the edge of the optical path regulating plate. It may be a thing.
Even in such a case, the resin lenses are welded to each other using a necessary optical path regulating plate. Since the optical path control plate absorbs light such as laser light and generates heat, if both the first transparent resin lens and the second transparent resin lens are in contact with the edge thereof, the first transparent resin is in that portion. The lens and the second transparent resin lens can be welded. As a result, the number of parts is small, assembly work is easy, and a lens arrangement positioned with high accuracy can be obtained.

Further, in the present invention, it is preferable that the flat portion of the first transparent resin lens and the flat portion of the second transparent resin lens are in contact with each other outside the optical path regulating plate.
For example, if the flat portions of the respective transparent resin lenses are continuous to the outer peripheral side from the edge of the optical path regulating plate, the first transparent resin lens and the second transparent resin lens are brought into contact with each other. Can be arranged. In this way, the distance between these lenses can be more precisely controlled by the abutting flat surface portion.

The combined lens of the present invention is a combined lens formed by combining a plurality of transparent resin lenses, the first and second transparent resin lenses having an effective aperture portion and a plane portion around the effective aperture portion, And an optical path regulating plate that is sandwiched between the flat portions of the second transparent resin lens and regulates the optical path. A part of the optical path regulating plate is melted and opened, and the first transparent portion is opened at the opened portion. The resin lens and the second transparent resin lens may be welded.
Even in such a case, the resin lenses are welded to each other using a necessary optical path regulating plate. In particular, when the optical path control plate is thin, it can absorb and melt light such as laser light, so that the first transparent resin lens and the second transparent resin lens can be directly welded at that portion. it can. As a result, the number of parts is small, assembly work is easy, and a lens arrangement positioned with high accuracy can be obtained.

In addition, the method for manufacturing a combined lens according to the present invention is a method for manufacturing a combined lens formed by combining a plurality of transparent resin lenses, and includes a first transparent resin and a second transparent resin having an effective aperture portion and a surrounding flat portion. The lenses are combined while holding the optical path regulating plate that regulates the optical path between the plane portions, and the first transparent resin lens and the optical path regulating plate are irradiated with the light, and the second transparent resin lens. It welds an optical path control board.
In this way, it is possible to easily assemble while maintaining the lens arrangement positioned with high accuracy.

In addition, the method for manufacturing a combined lens according to the present invention is a method for manufacturing a combined lens formed by combining a plurality of transparent resin lenses, and includes a first transparent resin and a second transparent resin having an effective aperture portion and a surrounding flat portion. The first and second transparent resin lenses are welded to each other by irradiating light to the edge of the optical path regulating plate while sandwiching the optical path regulating plate for regulating the optical path between them. It may be a thing.
Even in this case, the assembly operation can be easily performed while maintaining the lens arrangement positioned with high accuracy.

In addition, the method for manufacturing a combined lens according to the present invention is a method for manufacturing a combined lens formed by combining a plurality of transparent resin lenses, and includes a first transparent resin and a second transparent resin having an effective aperture portion and a surrounding flat portion. The lens is combined while holding the optical path regulating plate that regulates the optical path between the plane portions, and a part of the optical path regulating plate is melted and opened by light irradiation, and the first transparent portion is opened at the opened portion. The resin lens and the second transparent resin lens may be welded.
Even in this case, the assembly operation can be easily performed while maintaining the lens arrangement positioned with high accuracy.

  According to the assembled lens and the manufacturing method thereof of the present invention, the assembled lens and the manufacturing method thereof can be obtained with a small number of parts and easy assembling work, and a lens arrangement positioned with high accuracy.

"First form"
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, the present invention is applied to an optical lens set in which a plurality of optical lenses are combined.

  The optical lens set 1 of this embodiment is a combination of transparent resin lenses 11 and 12, as shown in FIG. Further, a donut plate-shaped optical path regulating plate 13 is sandwiched between the resin lenses 11 and 12. The resin lenses 11 and 12 are both joined to the optical path regulating plate 13 so that these three members are integrated.

  The resin lenses 11 and 12 are general transparent lenses each molded into an appropriate shape by a thermoplastic transparent resin. In both cases, edge portions 11b and 12b for joining and positioning are provided on the outer periphery of the effective regions 11a and 12a in the vicinity of the center of the optical axis. These resin lenses 11 and 12 are transparent to visible light and also transmit laser light well.

  The optical path regulating plate 13 is made of colored resin or is formed by applying a colored paint to a transparent member, blocks visible light, and absorbs laser light. The diameter of the inner peripheral side end of the optical path regulating plate 13 is substantially equal to the outer diameter of the smaller one of the effective regions 11a, 12a of the resin lenses 11, 12. The diameter of the outer peripheral side end of the optical path regulating plate 13 is substantially equal to the outer diameter of the resin lenses 11 and 12. From these, the optical path regulating plate 13 prevents light from being transmitted outside the effective areas 11a and 12a.

  The optical path regulating plate 13 is formed to have a predetermined uniform thickness, and the edge portions 11b and 12b of the resin lenses 11 and 12 are regulated at a predetermined interval by sandwiching the optical path regulating plate 13 therebetween. Therefore, the optical path regulating plate 13 also has a positioning function related to the distance between the resin lens 11 and the resin lens 12 in the optical axis direction.

  Furthermore, in this optical lens set 1, as shown in FIG. 1, the edge portion 12b of the resin lens 12 is provided with ventilation grooves 14 at predetermined locations. The space surrounded by the resin lenses 11 and 12 is communicated with the outside by the ventilation groove 14. Therefore, the air in the space or the gas generated inside during assembly can escape to the outside through the ventilation groove 14.

  If the ventilation groove 14 is not formed and this space is completely closed, assembly variation may occur due to expansion of air due to heating during welding and subsequent shrinkage due to cooling, or gas generated during welding may cause There is a possibility that the transparency of the resin lenses 11 and 12 may be lost, or even after completion, the internal air may expand due to environmental factors, heat, etc., and the resin lenses 11 and 12 may be deformed. In this optical lens set 1, since the ventilation groove 14 is provided, condensation inside the optical lens set 1 can be further prevented. The ventilation groove 14 may be formed in the resin lens 11.

  Next, a method for manufacturing such an optical lens set 1 will be described. First, the resin lens 11, the resin lens 12, and the optical path regulation plate 13 are formed of resin of each material. Next, these are combined in a predetermined arrangement, and as shown in FIG. 1, the edge portions 11b and 12b of the resin lenses 11 and 12 are irradiated with laser light such as an infrared laser from the left and right directions in the drawing. In this way, the laser light passes through the resin lenses 11 and 12 and is absorbed by the optical path regulating plate 13. Thereby, the portion of the optical path regulating plate 13 is heated and welded to the resin lenses 11 and 12 that are in contact with each other.

  The number of welding positions of these resin lenses 11 and 12 is preferably about three or six arranged symmetrically around the center of the optical axis. In this way, even if the joint surfaces of the resin lenses 11 and 12 are somewhat deformed at the time of welding, sufficiently precise positioning accuracy is maintained at the other large surface portions. Therefore, the resin lenses 11 and 12 can be reliably joined while maintaining high accuracy. It should be noted that the plurality of joining portions may be joined simultaneously by a plurality of laser heads, or may be joined in order by a small number of laser heads.

In addition, regarding the manufacturing method of this optical lens group 1, various devices can be devised as follows.
For example, when the optical path regulating plate 13 is very thin and both surfaces can be welded by laser light irradiation from one side, the irradiation may be performed from only one side. Furthermore, in this case, the optical path regulating plate 13 can be partially melted by laser light irradiation and the portion can be opened. In the opening portion, the resin lenses 11 and 12 come into contact with each other and receive heat from the optical path regulating plate 13, and the resin lenses 11 and 12 can be directly welded in this portion.

  Further, for example, a textured shape may be formed on the joint surface of the optical path regulating plate 13 with the resin lenses 11 and 12. As a result, the laser absorption at that portion is further improved. Alternatively, both bonding surfaces may be formed as mirror surfaces to improve the adhesion between the resins. As a result, heat is well transmitted to the resin lenses 11 and 12 that do not absorb laser light, and welding is ensured.

  For example, when the positioning accuracy between the resin lens 11 and the resin lens 12 is required to be higher, these resin lenses 11 and 12 and the optical path regulating plate 13 are fixed with high accuracy by a jig or the like. You may perform welding by a laser beam. In this way, positioning in the direction perpendicular to the optical axis can be performed with high accuracy.

  Further, for example, an infrared absorbing dye can be mixed in the optical path regulating plate 13 to provide a function as an infrared filter. At this time, it is preferable that the optical path regulating plate 13 is formed in a disc shape without a central hole so that the whole has an infrared ray absorbing function and a visible light absorbing region is provided in a donut shape.

  As described above in detail, according to the optical lens set 1 of the present embodiment, the optical path regulating plate 13 is sandwiched between the resin lenses 11 and 12, and the laser light is irradiated through the resin lenses 11 and 12. The optical path regulating plate 13 and the both resin lenses 11 and 12 are welded. Accordingly, the distance between the resin lens 11 and the resin lens 12 can be accurately positioned. As a result, the optical lens set 1 is obtained which has a small number of parts, can be easily assembled, and can obtain a lens arrangement positioned with high accuracy.

"Second form"
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, the present invention is applied to an optical lens set in which a plurality of optical lenses are combined.

  As shown in FIG. 2, the optical lens set 2 of the present embodiment is formed by joining transparent resin lenses 21 and 22 with an optical path regulating plate 23 interposed therebetween. The resin lenses 21 and 22 are general transparent lenses each formed into an appropriate shape by a thermoplastic transparent resin. In either case, edge portions 21b and 22b for bonding and positioning are provided on the outer periphery of the effective areas 21a and 22a in the vicinity of the center of the optical axis. These resin lenses 21 and 22 are transparent to visible light and transmit laser light well.

  The optical path regulating plate 23 is formed of a colored resin or is formed by applying a colored paint to a transparent member, blocks visible light, and absorbs laser light. The optical path regulating plate 23 has a donut shape, and the diameter of the inner peripheral end thereof is substantially equal to the outer diameter of the smaller one of the effective areas 21a and 22a of the resin lenses 21 and 22. And the diameter of the outer peripheral side end of the optical path regulating plate 23 is made smaller than the outer diameter of the resin lenses 21, 22, and the edge portions 21 b, 22 b of the resin lenses 21, 22 are in contact with each other on the outer peripheral side. Yes. That is, the outer diameter of the optical path regulating plate 23 is smaller than that of the optical path regulating plate 13 of the first embodiment.

  Further, in order to arrange in this way, a step is provided at the edge of the resin lens 21 or the resin lens 22. In the figure, a step is formed on the left surface of the edge portion 22b of the resin lens 22 in the figure. The resin lens 21 and the resin lens 22 are positioned with high accuracy in the optical axis direction by contacting the edge portions 21b and 22b with each other. The optical path regulating plate 23 also has a function of preventing light from entering the effective areas 21a and 22a through the outer peripheral side of the effective areas 21a and 22a of the resin lenses 21 and 22.

  Further, in this optical lens set 2, as in the first embodiment, the ventilation portion 22b of the resin lens 22 is provided with ventilation grooves 24 at predetermined locations. The space surrounded by the resin lenses 21 and 22 is communicated with the outside by the ventilation groove 24. Note that the ventilation groove 24 may be formed in the resin lens 21.

  Next, a method for manufacturing such an optical lens set 2 will be described. First, the resin lens 21, the resin lens 22, and the optical path regulating plate 23 are formed of resin of each material. Next, these are combined in a predetermined arrangement, and as shown in FIG. 2, the laser beam is irradiated to the outer peripheral side end of the optical path regulating plate 23 from the right direction in the drawing. In this way, the laser light passes through the resin lens 22 and is absorbed by the optical path regulating plate 23. Thereby, the edge part of the optical path control board 23 is heated, and the resin lenses 21 and 22 in contact with the position are welded to each other. The laser light may be irradiated from the resin lens 21 side.

  These resin lenses 21 and 22 are preferably welded at approximately three or six locations arranged symmetrically around the center of the optical axis. In this way, even if the joint surfaces of the resin lenses 21 and 22 are somewhat deformed during welding, sufficiently precise positioning accuracy is maintained at the other large surface portions. Therefore, the resin lenses 21 and 22 can be reliably bonded while maintaining high accuracy. It should be noted that the plurality of joining portions may be joined simultaneously by a plurality of laser heads, or may be joined in order by a small number of laser heads.

  In this embodiment, since both the resin lenses 21 and 22 in contact with the end of the optical path regulating plate 23 are heated and welded together, the optical path regulating plate 23 itself does not need to be welded. Rather, it is desirable to use a material that conducts heat well and resists deformation. Therefore, the material of the optical path regulating plate 23 is preferably a resin having higher heat resistance than the resin lenses 21 and 22. Alternatively, as the optical path regulating plate 23, a metal plate formed in a predetermined shape may be used.

  As described in detail above, the optical lens set 2 of the present embodiment also has the same number of parts as the optical lens set 1 of the first embodiment. can get.

"Third form"
Hereinafter, a third embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, the present invention is applied to an optical lens set in which a plurality of optical lenses are combined. The optical lens set 3 of this embodiment is different from the optical lens set 2 of the second embodiment only in the shape of the edge portion of the resin lens, and the other parts are the same. Omitted.

  In the optical lens set 3 of this embodiment, as shown in FIG. 3, transparent resin lenses 31 and 32 are joined with an optical path regulating plate 23 interposed therebetween. The resin lenses 31 and 32 are provided with edge portions 31b and 32b for bonding and positioning on the outer periphery of the effective areas 31a and 32a in the vicinity of the center of the optical axis. Further, as shown in FIGS. 3 and 4, the edge portions 31b and 32b of the resin lenses 31 and 32 are formed with depressions 31c and 32c on the contact surface with the optical path regulating plate 23, and further the outer periphery thereof. The sides are in contact with each other. The depth of the recesses 31c and 32c is preferably about 20 to 100 μm. These drawings show a state before the lens is welded.

  Further, in this optical lens set 3, as in the first and second embodiments, the ventilation portion 32b of the resin lens 32 is provided with ventilation grooves 34 at predetermined predetermined positions. The space surrounded by the resin lenses 31 and 32 is communicated with the outside by the ventilation groove 34. Note that the ventilation groove 34 may be formed in the resin lens 31.

  The optical lens set 3 is irradiated with laser light from both sides toward the depressions 31c and 32c as shown. The laser light passes through the resin lenses 31 and 32 and is absorbed by the optical path regulating plate 23, whereby the optical path regulating plate 23 at a portion facing the recesses 31c and 32c is heated. Thereby, the depressions 31c and 32c and the optical path regulating plate 23 are welded. At the time of welding, the resin expands slightly, and has some fluidity when dissolved, so that it can be welded even if it is not in a completely adhered state.

  According to the method of manufacturing the optical lens set 3, even if the resin in the welded portion expands to some extent during welding, there is no possibility that the outside contact portion will be affected by the expansion. Accordingly, the positioning of the resin lenses 31 and 32 is maintained with high positioning accuracy by the contact portion. The depressions 31c and 32c do not necessarily have to be formed over the entire circumference. You may form only in the part irradiated with a laser beam.

  As described in detail above, the optical lens set 3 of the present embodiment also has the same number of parts as the optical lens set 1 of the first embodiment, and is easy to assemble and has a lens arrangement positioned with high accuracy. can get.

In addition, each said form is only a mere illustration and does not limit this invention at all. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof.
For example, the shape and number of the lenses shown in the above embodiments are merely examples, and can be changed as appropriate according to the application.
The light beam used for welding is not limited to laser light, and any light beam that can be absorbed and generated by the optical path regulating plates 13 and 23 may be used.

It is a schematic sectional drawing which shows the optical lens group which concerns on a 1st form. It is a schematic sectional drawing which shows the optical lens group which concerns on a 2nd form. It is a schematic sectional drawing which shows the optical lens group which concerns on a 3rd form. It is explanatory drawing which shows the edge part of a resin lens.

Explanation of symbols

1 Optical lens group (assembled lens)
11, 12, 21, 22, 31, 32 Resin lens (transparent resin lens)
11a, 12a, 21a, 22a, 31a, 32a Effective area (effective diameter part)
11b, 12b, 21b, 22b, 31b, 32b Edge (plane part)
13, 23 Optical path regulating plate 31c, 32c Dimple

Claims (8)

In a combination lens composed of a plurality of transparent resin lenses,
First and second transparent resin lenses having an effective aperture portion and a flat portion around the effective aperture portion;
An optical path regulating plate sandwiched between the flat portions of the first and second transparent resin lenses and regulating an optical path;
An assembled lens, wherein the first transparent resin lens and the optical path regulating plate are welded together, and the second transparent resin lens and the optical path regulating plate are welded together. The group lens according to claim 1,
An assembled lens, wherein a recess is formed in one of the transparent resin lens and the optical path regulating plate at a welding position between the first or second transparent resin lens and the optical path regulating plate. In a combination lens composed of a plurality of transparent resin lenses,
First and second transparent resin lenses having an effective aperture portion and a flat portion around the effective aperture portion;
An optical path regulating plate that is sandwiched between the first and second transparent resin lenses and regulates the optical path;
An assembled lens, wherein the first transparent resin lens and the second transparent resin lens are welded together at an edge of the optical path regulating plate. In the combination lens according to claim 3,
An assembled lens, wherein the planar portion of the first transparent resin lens and the planar portion of the second transparent resin lens are in contact with each other outside the optical path regulating plate. In a combination lens composed of a plurality of transparent resin lenses,
First and second transparent resin lenses having an effective aperture portion and a flat portion around the effective aperture portion;
An optical path regulating plate sandwiched between the flat portions of the first and second transparent resin lenses and regulating an optical path;
A combined lens, wherein a part of the optical path regulating plate is melted and opened, and the first transparent resin lens and the second transparent resin lens are welded at the opened part. In a manufacturing method of a combined lens formed by combining a plurality of transparent resin lenses,
First and second transparent resin lenses having an effective aperture portion and a flat portion around the effective aperture portion,
Combining them while sandwiching an optical path regulating plate that regulates the optical path between these flat parts,
A method for manufacturing a combined lens, comprising: welding the first transparent resin lens and the optical path regulating plate, and welding the second transparent resin lens and the optical path regulating plate by light irradiation. In a manufacturing method of a combined lens formed by combining a plurality of transparent resin lenses,
First and second transparent resin lenses having an effective aperture portion and a flat portion around the effective aperture portion,
The optical path regulating plate that regulates the optical path is sandwiched between them and combined,
A method of manufacturing a combined lens, wherein the first transparent resin lens and the second transparent resin lens are welded by irradiating light to an edge of the optical path regulating plate. In a manufacturing method of a combined lens formed by combining a plurality of transparent resin lenses,
First and second transparent resin lenses having an effective aperture portion and a flat portion around the effective aperture portion,
Combining them while sandwiching an optical path regulating plate that regulates the optical path between these flat parts,
A combined lens, wherein a part of the optical path regulating plate is melted and opened by light irradiation, and the first transparent resin lens and the second transparent resin lens are welded at the opened part. Manufacturing method.

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