JP2007086367A - Optical pin, optical pin connector and optical path conversion module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pin in which the fitness between a metallic layer and an optical fiber is excellent, the peeling of the metallic layer is prevented and the transmission of optical signal is excellent. <P>SOLUTION: The optical pin 10 is provided with: a first light input/output face 12 located at the end part of an optical fiber 11 having a core 11a which extends in axial direction and a clad 11b which encloses the core 11a; a light reflecting face 13 located at the other end part of the optical fiber 11; the metallic layer 14 which clads the optical reflecting face 13, substantially clads the core 11a at the central part and also clads the one side face of the optical fiber over the length L<SB>0</SB>by being made contact with the outer peripheral part of the light reflecting face 13; and a second light input/output face 15 which is adjacent to the other end of the optical fiber 11 and exposes the optical fiber 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an optical pin, an optical pin connector, and an optical path conversion module.

As a technique for forming a metal mirror on an optical fiber, after sensitizing the surface of the optical fiber with SnF ₂ and activating with PdCl ₂ / HCl, the adhesion of gold to the optical fiber is applied to the end surface of the optical fiber. It is sufficient to strengthen, but to act as an obstacle to the radiation transmission of the gold thin film layer, a Ni—P adhesive layer of insufficient thickness is deposited and then passed through this adhesive layer. A technique for forming a gold layer (metal mirror) is disclosed (for example, see Patent Document 1).
JP-A-8-271707

However, when the metal mirror is formed on the end face of the optical fiber by the technique disclosed in Patent Document 1, it is necessary to form an adhesive layer between the optical fiber and the metal layer. In addition, the metal mirror formed may not have sufficient adhesiveness, and peeling may occur.

The inventor of the present application diligently studied to solve the above-mentioned problems, and forms an optical pin having a metal mirror excellent in adhesion to the optical fiber by forming a metal layer on part of the end face and side face of the optical fiber. As a result, the optical pin of the present invention was completed.
Furthermore, the optical pin connector and optical path conversion module of the present invention using the optical pin were also completed.

An optical pin according to the present invention includes a first light input / output surface located at an end portion of an optical fiber having a core extending in the axial direction and a clad surrounding the core, and light located at the other end portion of the optical fiber. A reflective surface, a metal layer that covers the light reflecting surface and that also touches the outer edge of the light reflecting surface and covers one side of the optical fiber, and an optical fiber that is adjacent to the other end of the optical fiber and exposes the optical fiber The gist is to provide the second light input / output surface.

The optical pin connector according to the present invention is positioned at the first light input / output surface located at the end of the optical fiber having a core extending in the axial direction and the clad surrounding the core, and at the other end of the optical fiber. A light reflection surface, a metal layer that covers the light reflection surface and that also contacts the outer edge of the light reflection surface and covers one side surface of the optical fiber; and an optical fiber adjacent to the other end of the optical fiber, The optical pin having the exposed second light input / output surface, the plurality of through holes corresponding to the plurality of optical pins arranged in parallel in the axial direction, and the through hole are traversed in a direction perpendicular to the axial direction. The gist of the invention is to include a connector main body having a slit portion and inserting the optical pin into the through hole, and an adhesive filling the slit portion and fixing the optical pin to the connector main body.

An optical path conversion module according to the present invention includes a first light input / output surface located at an end of an optical fiber having a core extending in the axial direction and a clad surrounding the core, and located at the other end of the optical fiber. A light reflecting surface, a metal layer covering the light reflecting surface and in contact with the outer edge of the light reflecting surface and covering one side surface of the optical fiber, and an optical fiber adjacent to the other end of the optical fiber, An optical pin having a second light input / output surface exposed, an optical element that emits or receives an optical signal to the optical pin, and a drive integrated circuit that is electrically connected to the optical element and drives the optical element A plurality of through-holes corresponding to a plurality of optical pins arranged in parallel in the axial direction, a slit portion that crosses the through-hole in a direction perpendicular to the axial direction, a connector body that inserts the optical pin into the through-hole, and a through Projecting from the connector body adjacent to the row of holes Optical pin connector for fixing the optical pin to the connector body, and a guide hole provided corresponding to each of the plurality of guide pins. The gist of the present invention is to provide a circuit board on which an element and a driving integrated circuit are mounted, and a guide pin is inserted into the guide hole to position and transmit an optical signal between the optical element and the optical pin.

In the optical pin of the present invention, since the metal layer is formed on the light reflecting surface, the light path can be reliably converted on the light reflecting surface, and in addition, the light reflecting surface and a part of the side surface of the optical fiber Since the metal layer which covers is provided, the adhesiveness between the metal layer and the optical fiber is high, and peeling of the metal layer can be avoided. Therefore, the optical pin of the present invention has excellent reliability in terms of optical signal transmission.

Further, in the optical pin connector of the present invention, a plurality of optical pins are fixed to the connector body with an adhesive, and the optical pins can be disposed at predetermined positions, and the optical path is routed through the optical pins. An optical signal can be reliably transmitted while converting.

In the optical path conversion module of the present invention, an optical signal can be reliably transmitted between the optical element and the optical pin connector (optical pin).
Further, since the alignment between the optical element and the optical pin connector (optical pin) can be performed by passive alignment, manufacturing is easy, and replacement work of the optical pin connector and the like is also easy.

An optical pin according to a first embodiment of the present invention will be described with reference to the drawings.
For example, as shown in FIG. 1, the optical pin 10 includes a first light input / output surface 12 positioned at an end of an optical fiber 11 having a core 11a extending in the axial direction and a clad 11b surrounding the core 11a. The light reflecting surface 13 located at the other end of the optical fiber 11, covers the light reflecting surface 13, contacts the outer edge of the light reflecting surface 13, and substantially covers the core 11 a at the center. A metal layer 14 that also covers one side of the optical fiber over L ₀ and a second light input / output surface 15 that is adjacent to the other end of the optical fiber 11 and exposes the optical fiber 11 are provided.
1A is a side view of an optical pin according to an embodiment of the present invention, FIG. 1B is a front view of the optical pin shown in FIG. 1A, and FIG. It is A sectional view.

Such an optical pin 10 can transmit an optical signal and can change the angle of the optical path by 90 °.
Specifically, when an optical signal irradiated from a light source (not shown) such as an LD is incident from the first light input / output surface 12, the optical signal is reflected on the light reflecting surface 13 via the core 11 a of the optical fiber 11. After being transmitted toward the optical path, the optical path is converted by 90 ° by reflection at the light reflecting surface 13 and emitted from the second light input / output surface 15, and an optical signal (not shown) such as a PD is transmitted. Can be transmitted.
Here, the optical path in which the light incident from the first light input / output surface 12 is emitted from the second light input / output surface 15 has been described. However, in the optical pin 10, the opposite optical path, that is, Even when the light incident from the second light input / output surface 15 is emitted from the first light input / output surface 12, an optical signal can be transmitted and the angle of the light path can be converted by 90 °. .
Further, in the optical pin 10, since the light reflecting surface 13 forms an angle of 45 ° with the core 11a, the optical path is converted by 90 °. However, in the optical pin according to the embodiment of the present invention, the light reflection is performed. The angle formed by the surface and the core is not limited to 45 °, and the optical path can be converted at a desired angle by arbitrarily setting this angle.

The optical pin 10 includes a metal layer 14 that covers a part of the side surface of the light reflecting surface 13 and the optical fiber 11. By forming the metal layer 14 so as to cover the light reflecting surface 13, light is not transmitted through the light reflecting surface 13, and the optical path can be reliably converted.
In the optical pin 10, a metal layer 14 is formed on a part of the side surface of the optical fiber 11 together with the light reflecting surface 13. Thus, by forming the metal layer 14 integrally not only on the light reflecting surface 13 but also on a part of the optical fiber 11, the adhesion between the metal layer 14 and the optical fiber 11 is improved. It is possible to avoid peeling of the layer 14.

The material of the metal layer 14 is not particularly limited, and various metals can be used. However, Au is desirable because it has a high reflectance and a metal layer having stable characteristics can be easily produced.
The formation position of the metal layer 14 is a part of the side surface of the light reflecting surface 13 and the optical fiber 11, but the formation position of the metal layer 14 on the side surface of the optical fiber 11 is a region other than the second light input / output surface 15. As long as it is a region that does not overlap the second light input / output surface 15, it may be formed in any range on the side surface of the optical fiber.
The second light input / output surface 15 is a lower projection surface of the end surface of the core 11a constituting the light reflection surface 13, and is a projection surface on the side surface of the optical fiber.

Further, the formation position of the metal layer 14 on the side surface of the optical fiber 11 is desirably formed in a position that forms an arc that occupies 1/2 or more of the circumference in the cross section along the line AA of the optical pin 10. As shown in FIG. 1B, it is more desirable that both end portions of the metal layer 14 are located below the virtual horizontal line passing through the center of the core.
By forming in such a position, adhesiveness with the optical fiber is further improved, and peeling of the metal layer can be avoided more reliably.

The length of the metal layer 14 on the side surface of the optical fiber 11 is preferably longer than the length of the longest portion of the light reflecting surface 13.
This is because by forming the metal layer 14 in this manner, the adhesion to the optical fiber is further improved, and the peeling of the metal layer can be avoided more reliably.
The length of the metal layer 14 of the side surface portion of the optical fiber 11 and refers to the length of the shortest portion in the axial direction of the optical fiber on the side surface of the optical fiber 11, in FIG. 1 (a), part of the L ₀ Say length.

The thickness of the metal layer 14 is not particularly limited, but is usually in the range of 0.1 to 1.0 μm. Desirably, the range of 0.3 to 0.5 μm is preferable.
If the metal layer is too thin, pinholes are formed in the metal layer, which may not function reliably as a mirror. On the other hand, even if the thickness is increased, the cost increases and time is required for formation. This is because it is difficult to desire an improvement in adhesiveness with an optical fiber.
A method of forming the metal layer 14 will be described in detail later, but when the material of the metal layer 14 is Au, it can be formed by sputtering or the like.

The optical fiber 11 is not particularly limited, and specific examples thereof include, for example, a multi-component mainly composed of silica-based optical fiber mainly composed of quartz glass (SiO ₂ ), soda lime, glass, borosilicate glass and the like. Examples thereof include plastic optical fibers mainly composed of plastics such as silicone resins and acrylic resins.

The optical pins of the embodiments of the present invention described so far are single-core optical pins, but the optical pins of the embodiments of the present invention are also used as multi-core optical pins by arranging a plurality of optical pins in parallel. can do.

Next, a method for manufacturing the optical pin of the embodiment of the present invention will be described with reference to the drawings.
Here, a manufacturing method will be described by taking as an example the case of manufacturing a multi-core optical pin using an optical fiber ribbon as a starting material.
2A to 2C are schematic views showing a process for manufacturing an optical pin according to an embodiment of the present invention.

(1) First, as shown in FIG. 2A, an optical fiber ribbon 20 (multi-core optical fiber) from which the coating near one end is removed is prepared.
Then, the optical fiber ribbon 20 is placed on the glass substrate 21 with the V-groove formed thereon, and further, the lid substrate 22 is placed on the optical fiber ribbon 20, and then the adhesive 23 is filled. The optical fiber ribbon 20 is fixed with an adhesive 23 by being sandwiched between the lid substrate 22 (see FIG. 2B-1).

(2) Next, a polishing process is performed on one end (side from which the coating is removed) of the optical fiber ribbon 20 to form a light reflecting surface (see FIG. 2B-2). In this polishing process, for example, rough polishing and finish polishing may be performed in this order.
The glass substrate 21 and the lid substrate 22 are polished so that one of the end surfaces forms an inclination of 45 ° with the bottom surface.
A 45 ° light reflecting surface can be formed on the optical fiber ribbon 20 sandwiched between the glass substrate 21 and the lid substrate 22 inclined at 45 °.
The inclination of the glass substrate 21 and the lid substrate 22 is not limited to 45 °, and may be any angle.

(3) Next, the optical fiber ribbon 20 is removed from the glass substrate 21, the lid substrate 22 and the adhesive 23, and if necessary, impurities (for example, adhesive) attached to the optical fiber are subjected to ultrasonic cleaning (for example, For 5 minutes).
By performing such polishing and cleaning treatments, the light reflecting surface can be a flat surface having a surface roughness of about 10 nm.

(4) Next, the light reflecting surface of the optical fiber ribbon 20 is covered, and a band-shaped metal layer is formed that is a part of the side surface of the optical fiber ribbon 20 and is in contact with the outer edge of the light reflecting surface.
As shown in FIG. 2 (c), the optical fiber ribbon 20 is mounted on a glass substrate 24 with a V-groove, and the upper surface of the optical fiber ribbon 20 is exposed so that the light reflecting surface of the optical fiber and the band-shaped metal layer forming region are exposed. A flame-retardant fixing tape 25 is adhered to the optical fiber ribbon 20 and the optical fiber ribbon 20 is fixed to the V-grooved glass substrate 24.

Although the state in which the end of the optical fiber ribbon 20 is fixed in alignment with the end inclined surface of the V-grooved glass substrate 24 is illustrated, in this step, the end of the optical fiber ribbon 20 is attached to the end inclined surface. For example, the end portion of the optical fiber ribbon 20 is positioned in the middle region of the V groove extending in the longitudinal direction of the glass substrate 24 with the V groove, and the optical fiber ribbon 20 is fixed to the V by the fixing tape 25. You may fix to the glass substrate 24 with a groove | channel.

Subsequently, a reverse sputtering process is performed. In the embodiment of the present invention, the reverse sputtering process introduces the optical fiber ribbon 20 as an optical pin fixed to the V-grooved glass substrate 24 into the vacuum chamber, and the moisture and / or adhering to the optical fiber ribbon 20 is introduced. This corresponds to the step of removing impurities.

In the reverse sputtering process, for example, the inside of the vacuum chamber is kept at a high temperature of about 10 minutes at 130 ° C. under atmospheric pressure, and after the moisture in the vacuum chamber is removed, the temperature raising process is canceled. Thereafter, when the inside of the vacuum chamber is changed from a high temperature state to a normal temperature, the inside of the vacuum chamber is changed to a vacuum state by a vacuum pump (not shown).

When the vacuum pump is operated continuously for about 8 hours in the vacuum chamber, the degree of vacuum changes to 8.98 × 10 ⁻⁴ Pa.
In this state, argon (Ar) gas is introduced from the outside into the vacuum chamber, plasma is generated in the vacuum chamber, and activated Ar ⁺ ions collide with the optical fiber ribbon 20 exposed to the Ar gas atmosphere. The plasma generation period is set to about 10 minutes to remove moisture and / or impurities from the optical fiber ribbon 20. In this case, the inside of the vacuum chamber is set to room temperature, but the temperature of the surface of the optical fiber ribbon 20 rises in the range of about 30 ° C. to 40 ° C. during the plasma irradiation period.

By performing such reverse sputtering, moisture and / or impurities in the region where the Au film is formed can be more reliably removed, and the surface roughness of the region where the Au film is formed is increased. The adhesion of the Au film is further improved by the anchor effect.

Thereafter, Au sputtering is performed to form a metal layer (Au film) on the light reflecting surface and part of the side surface of the optical fiber ribbon 20.
The Au sputtering conditions are not particularly limited, and may be set as appropriate in consideration of the thickness of the Au film to be formed. For example, when the thickness of the Au film is 0.5 μm, the gas: Ar, Time: 15 minutes, degree of vacuum: 8.98 × 10 ⁻⁴ Pa, an Au film can be formed.
By performing such Au sputtering, an Au film can be formed so as to cover the vicinity of the end portion of the optical fiber 11 including the light reflecting surface 13 of the optical fiber 11. It will have excellent adhesion.

The optical pin according to the embodiment can be manufactured by using the optical fiber ribbon 20 through the reverse sputtering process and the Au sputtering process.
In addition, here, a method for manufacturing a multi-core optical pin using an optical fiber ribbon has been described. However, if a single-core optical fiber is used as a starting material, a single-core optical pin is also manufactured by a similar method. be able to.

Next, an optical pin connector according to a second embodiment of the present invention will be described.
The optical pin connector 30 includes a first light input / output surface 12 positioned at an end of the optical fiber 11 having a core 11a extending in the axial direction and a clad 11b surrounding the core 11a, and the other end of the optical fiber 11. A light reflecting surface 13 positioned at the surface, a metal layer 14 that covers the light reflecting surface 13 and also covers one side of the optical fiber 11 in contact with the outer edge of the light reflecting surface 13, and the other end of the optical fiber 11. And a plurality of through holes 33a corresponding to the plurality of optical pins 10a to 10d arranged in parallel in the axial direction, and the second optical input / output surface 15 exposing the optical fiber 11. 33d and a slit body 34 that crosses the through holes 33a to 33d in a direction perpendicular to the axial direction, and the connector body 31 that inserts the optical pin 10 into the through hole, and the slit section 34 are filled, Connect optical pin 10 It includes an adhesive 32 for fixing the motor body 31, a.

3-1 (a) is a perspective view showing an example of an optical pin connector according to an embodiment of the present invention, (b) is a front view of the optical pin connector shown in (a), (c) ) Is a plan view of the optical pin connector shown in FIG.
3D is a cross-sectional view taken along line BB in FIG. 3A, and FIG. 3E is a perspective view showing only the connector main body that constitutes the optical pin connector shown in FIG. It is.

As shown in FIGS. 3A and 3B, the optical pin connector 30 includes a plurality of optical pins (multi-core optical pins) 10 (10a to 10d) according to the first embodiment and a plurality of optical pins penetrating through the optical pins. Connector body having a through hole 33 and a slit portion 34 provided so as to cross at least a part of the through hole 33, and the optical pin 10 is inserted into the through hole 33 and arranged in parallel. 31 and an adhesive 32 that fills the slit portion 34 and fixes the optical pin 10 to the connector main body 31.
In addition, although the number of the optical pins with which the optical pin connector 30 is provided is four, the number of the optical pins with which the optical pin connector of embodiment of this invention is provided is not limited to four, Any number may be sufficient.

As shown in FIG. 3-2 (e), the connector body 31 is formed with through holes 33 (33 a to 33 d) for holding the optical pins 10, and the optical pins 10 are inserted into the through holes 33. It will be inserted. The connector main body 31 is provided with a slit portion 34 so as to cross the through hole 33. The slit portion 34 is filled with an adhesive 32 for fixing the optical pin.

In the connector main body 31 shown here, the slit portion 34 is formed so as to traverse the entire through-hole 33. However, in the optical pin connector according to the embodiment of the present invention, the slit portion has only a part of the through-hole. You may form so that it may cross.
That is, in the optical pin connector 30, the bottom surface of the slit portion 34 is formed to be positioned below the through hole 33, but the bottom surface of the slit portion is formed to be positioned in the through hole. It may be.
The width of the slit portion 34 (in the figure, _{L 1),} if it is large enough to be able to be reliably filled with the adhesive 32 in the slit portion 34 is not particularly limited, usually, is about 150~400μm .

As the connector body 31, for example, an MT connector (Mechanically Transferable Connector) can be used. By forming a slit portion in the MT connector by cutting, the connector body 31 can be obtained.
The MT connector includes, for example, two guide pins, and the use of a part of the MT connector including such guide pins as a connector main body is an optical pin used for an optical path conversion module described later. This is useful in terms of a connector.

In addition, some MT connectors include an adhesive filling portion for filling an adhesive for fixing an optical fiber together with a through hole through which the optical fiber is inserted. It can function as a slit portion constituting the optical pin connector of the embodiment.
However, in this MT connector, the distance between the surface from which the light reflecting surface of the optical pin protrudes and the adhesive filling portion is long (approximately 2 to 3 mm).
On the other hand, various optical components such as an optical pin connector are desired to be small in order to cope with downsizing of the apparatus. In the optical pin connector according to the embodiment of the present invention, the length of the connector body (the length in the through-hole forming direction) is reduced to about 2 to 3 mm in consideration of the function, configuration, handleability, and the like. Is desirable. Therefore, when the MT connector is used as the connector main body constituting the optical pin connector of the embodiment of the present invention, it is desirable to use only a part thereof and separately form the optical slit portion.

Examples of the adhesive 32 include a thermosetting resin, a resin in which a part of the thermosetting resin is sensitized, and a photosensitive resin.
Specifically, for example, a thermosetting resin such as an epoxy resin, a phenol resin, or a silicone resin, an ultraviolet curable resin, or the like can be used.

The size (diameter) of the through hole 33 is not particularly limited, and may be appropriately selected in consideration of the size of the optical fiber constituting the optical pin to be inserted.
Specifically, for example, when the diameter of the optical fiber constituting the optical pin is 125 μm,
A through hole having a slightly larger diameter of about 126 μm may be formed. In addition, what is necessary is just to set the clearance of an optical fiber and the through-hole 33 in the range of 0.3-0.5 micrometer according to the thickness of a metal layer.
This is because if the size of the through hole 33 is too large compared to the size of the optical fiber, the optical pin 10 may be displaced in the through hole 33.

In the optical pin connector 30, the protruding length from the connector main body on the light reflection surface side of the optical pin 10 is not particularly limited, and may be appropriately selected according to the design.
Further, in the optical pin connector 30, the protruding length of the optical pin 10 from the connector body on the first light input / output surface side is not particularly limited, and the first light input / output surface and the connector body side surface are the same surface. (The length does not protrude and the length is 0), or may protrude by a predetermined length.

In the optical pin connector 30, the optical path converted by each of the optical pins 10a to 10d has a conversion angle of 90 degrees and the same conversion direction (when input from the first light input / output surface, all are downward. However, in the optical pin connector according to the embodiment of the present invention, the conversion angle and the conversion direction may be different for each optical pin.

In the optical pin connector of the embodiment of the present invention, a plurality of optical pins arranged in parallel may be stacked in two or more stages.
3-3 (a) is a perspective view schematically showing another example of the optical pin connector according to the embodiment of the present invention, and (b) is a cross-sectional view taken along the line CC of (a). .

As shown in FIG. 3C, in the optical pin connector 40, a plurality of optical pins (multi-core optical pins) 10 (10a to 10h) according to the first embodiment and the optical pins 10 are arranged in parallel. A connector body 41 that is held in a state in which it is held, an adhesive 42 that fixes the optical pin 10 to the connector body 41, a through-hole that is provided so as to penetrate the connector body 41, and holds the optical pin 10 therein, and a through hole And a slit portion that is provided so as to cross at least a part of the hole and is filled with an adhesive 42 therein.
Here, in the optical pin 10, the optical pins 10a to 10d are arranged in parallel as one set, and the optical pins 10e to 10h are arranged in parallel as another set. The optical pins 10a to 10d are fixed to the upper stage, and the optical pins 10e to 10h are fixed to the lower stage.
Thus, in the optical pin connector according to the embodiment of the present invention, the optical pins arranged in parallel may be stacked in a plurality of stages.

In the optical pin connector 40, the protruding length of the optical pins 10a to 10d from the connector main body 41 on the light reflecting surface side is longer than the protruding length of the optical pins 10e to 10h from the connector main body 41 on the light reflecting surface side. It is comprised so that it may become. By adopting such a configuration, it is possible to prevent an optical signal whose optical path has been converted by each optical pin from being inhibited from being transmitted by other optical pins.
The configuration of the optical pin connector 40 is the same as the optical pin connector 30 shown in FIGS. 3A and 3B except that the optical pins arranged in parallel are stacked in a plurality of stages. Explanation of the members is omitted.
Even in such an optical pin connector, the functions and effects of the optical pin connector of the present invention described above can be enjoyed.

In addition, in the configuration in which the optical pins arranged in parallel, such as the optical pin connector 40, are stacked in a plurality of stages, the conversion angle and the conversion direction of each optical pin may all be the same, It may be different for each optical pin.
For example, when the light is input from the first light input / output surface, the optical path may be converted upward in the upper optical pin, and the optical path may be converted downward in the lower optical pin. In this case, the protrusion length from the connector main body on the light reflection surface side of the upper and lower optical pins may be the same.

Next, a method for manufacturing the optical pin connector of the embodiment of the present invention will be described.
Here, a method for manufacturing an optical pin connector will be described using a method using an MT connector as an example.
A multi-core optical pin and an MT connector through which the optical pin can be inserted are prepared.
First, the MT connector is cut into a predetermined size, and a slit portion is formed by cutting. As described above, the slit portion may be formed so as to cross the entire through hole, or may be formed so as to cross only a part of the through hole.

Next, each optical pin constituting this multi-core optical pin is inserted into the through hole of the MT connector.
The multi-core optical pins manufactured by the above-described method may have pitch mismatch or length variation between the optical pins. However, by using the MT connector, the pitch between the optical pins can be reduced. Can be aligned.
The adjustment of the length variation between the pins (positional accuracy adjustment) can be performed using an automatic aligner. Here, it is desirable to use an automatic aligner having an alignment accuracy of about 1 μm.

Thereafter, the uncured adhesive is filled in the slit portion, and the uncured adhesive is cured under predetermined conditions such as heating and ultraviolet irradiation, thereby fixing the multi-core optical pins to the connector body.
By passing through such a process, the optical pin connector of embodiment of this invention can be manufactured.

Next, an optical path conversion module according to a third embodiment of the present invention will be described.
The optical path conversion module 100 includes a first light input / output surface 12 located at an end of an optical fiber 11 having a core 11a extending in the axial direction and a clad 11b surrounding the core 11a, and the other end of the optical fiber 11. A light reflection surface 13 positioned at the portion, a metal layer 14 that covers the light reflection surface 13 and also covers one side surface of the optical fiber 11 in contact with the outer edge of the light reflection surface 13, and the optical fiber 11 An optical pin 10 having a second light input / output surface 15 adjacent to the other end and exposing the optical fiber 11, an optical element 102 for emitting or receiving an optical signal to the optical pin 10, and an optical element 102 A driving integrated circuit 103 that is electrically connected and drives the optical element 102, a plurality of through-holes 33 corresponding to a plurality of optical pins 10 that are arranged in parallel in the axial direction, and the through-holes 33 with respect to the axial direction. Vertical Adhering to the slit portion 34 is a crossing slit portion 34, a connector main body 31 for inserting the optical pin 10 into the through hole, and a plurality of guide pins 39 protruding from the connector main body 31 adjacent to the row of the through holes 33. The optical pin connector 30 that fills the agent 32 and fixes the optical pin 10 to the connector main body 31, and the guide holes 112 c provided respectively corresponding to the plurality of guide pins 39, the optical element 102 and the drive integrated circuit 103. And a circuit board 101 for positioning the optical signal between the optical element 102 and the optical pin 10 by inserting the guide pin 39 into the guide hole 112c.

4A is a cross-sectional view schematically illustrating an example of the optical path conversion module according to the embodiment of the present invention, and FIG. 4B is a cross-sectional view taken along the line DD in FIG.
4-2 (c) is a partial perspective view of the interposer constituting the optical path changing module shown in FIG. 4-1 (a), and (d) is shown in FIG. 4-1 (a). It is a perspective view of the lens array which comprises the module for optical path conversion.

As shown in FIGS. 4A and 4B, the optical path conversion module 100 includes an optical element 102 and a driving integrated circuit 103, the optical pin connector 30 according to the second embodiment described above, a conductor circuit 101b, and an insulating layer 101a. And a circuit board 101 that is laminated.
On one surface of the circuit board 101, an optical element 102 is mounted by solder bumps 104, and a driving integrated circuit 103 is mounted by wire bonding 105. A solder resist layer 108 and solder bumps 109 are formed on the other surface of the circuit board 101. In the figure, reference numeral 103a denotes a die pad.

An interposer 110 is attached to the side of the circuit board 101 on which the optical element 102 and the like are mounted so as to cover the entire circuit board 101, and on the inner side of the interposer 110 (side facing the circuit board 101) The lens array 111 is fixed. Further, the optical pin connector 30 is attached to the interposer 110.
Here, the optical pin connector 30 includes two guide pins 39, and the circuit board 101, the lens array 111, and the interposer 110 include guide holes 112 a to 112 c at two locations, respectively. The pins 39 are inserted through guide holes 112a to 112c provided in the interposer 110, the lens array 111, and the circuit board 101 in this order. Therefore, the interposer 110, the lens array 111, and the circuit board 101 are aligned by the guide pins 39, and the optical element 102 mounted on the circuit board 101 constitutes the optical pin connector 30 via the lens 111a. The optical signal can be transmitted to and from the optical pin 10 to be transmitted.

In the optical path conversion module 100, guide holes 112a to 112c are formed at predetermined positions of the interposer 110, the lens array 111, and the circuit board 101, and optical elements are mounted at predetermined positions of the circuit board 101. Accordingly, the optical element and the optical pin connector (optical pin) can be aligned only by inserting the guide pin 39 attached to the optical pin connector 30 into the guide holes 112a to 112c.
That is, in the optical path conversion module 100, the alignment between the optical element 102 and the optical pin connector 30 (optical pin 10) can be performed by passive alignment.
Therefore, the optical path conversion module according to the embodiment of the present invention does not require alignment by active alignment, so that it can be easily manufactured, and an optical pin connector or the like can be easily replaced.
Furthermore, in the optical path conversion module according to the embodiment of the present invention, the optical pin connector can be easily attached and detached, and the optical pin connector can be appropriately replaced with respect to a plurality of circuit boards.

The optical pin connector 30 constituting the optical path conversion module 100 is the optical pin connector according to the second embodiment described above.
Two guide pins 39 are attached to the optical pin connector 30. Here, the number of guide pins is not particularly limited, and may be two or more.
The manner in which the guide pins are attached is not particularly limited, but an embodiment in which the guide pins are fixed by being sandwiched between connector bodies constituting the optical pins is desirable. This is because the guide pin is securely fixed.
Therefore, it is desirable that the connector main body of the optical pin connector constituting the optical path changing module according to the embodiment of the present invention uses a part of the MT connector as described above.

Further, in the optical pin connector constituting the optical path conversion module, the first light input / output surface of each optical pin may form the same plane as the side surface of the connector body, or protrude from the side surface of the connector body. It may be. Which one should be selected may be selected according to the design of the optical path conversion module of the optical path conversion module.
Further, when the first light input / output surface protrudes from the side surface of the connector body, the length thereof is arbitrary. For example, in the optical path conversion module 100 shown in FIGS. It is the same as the thickness of a region for attaching 110 optical pin connectors 30 (see 110a in FIG. 4-2 (c)).

The circuit board 101 constituting the optical path conversion module 100 is formed by laminating an insulating layer 101a and a conductor circuit 101b on both sides of an insulating layer 101a having a conductor circuit 101b formed on both sides thereof. A solder resist layer 108 and solder bumps 109 are formed on the outer layer. In addition, the conductor circuits 101b at different levels are electrically connected through the through holes 101c.
The circuit board constituting the optical path conversion module according to the embodiment of the present invention is not limited to such a structure as long as the guide hole is formed. For example, a circuit board in which a guide hole is formed in a package substrate. Can be used. Therefore, the total number of conductor circuits and insulating layers is arbitrary, and the presence or absence of a solder resist layer is also arbitrary.

An optical element 102 and a driving integrated circuit 103 are mounted on the optical path conversion module 100.
As the optical element, a light receiving element, a light emitting element, or the like can be used.
Examples of the light receiving element include PD (photodiode), APD (avalanche photodiode), and the like.
These may be properly used in consideration of the configuration of the optical path conversion module, required characteristics, and the like.
Examples of the material for the light receiving element include Si, Ge, and InGaAs.
Of these, InGaAs is desirable because of its excellent light receiving sensitivity.

Examples of the light emitting element include LD (semiconductor laser), DFB-LD (distributed feedback type-semiconductor laser), LED (light emitting diode), infrastructure type or oxide constriction type VCSEL (surface emitting semiconductor laser). .
These may be properly used in consideration of the configuration and required characteristics of the optical path conversion module.

Examples of the material of the light emitting element include a compound of gallium, arsenic and phosphorus (GaAsP), a compound of gallium, aluminum and arsenic (GaAlAs), a compound of gallium and arsenic (GaAs), a compound of indium, gallium and arsenic (InGaAs), Indium, gallium, arsenic and phosphorus compounds (InGaAsP) can be used.
These may be properly used in consideration of the communication wavelength. For example, when the communication wavelength is 0.85 μm band, GaAlAs can be used, and when the communication wavelength is 1.3 μm band or 1.55 μm band. InGaAs or InGaAsP can be used.

Each of these light-emitting elements and light-receiving elements may be a single channel element or a multi-channel array element. Which one is selected depends on the optical pin of the optical pin connector. What is necessary is just to select suitably in consideration of the number etc. Of course, a plurality of single-channel elements and multi-channel array elements may be mounted.
As the driving integrated circuit, a circuit suitable for driving the optical element (light receiving element or light emitting element) may be used.

In the optical path conversion module 100 shown in FIGS. 4A and 4B, only one optical element and one driving integrated circuit are mounted, but in the optical path conversion module according to the embodiment of the present invention, a circuit board is provided. The number of optical elements and driving integrated circuits mounted on the circuit board is not particularly limited, and a plurality of optical elements may be mounted on one circuit board.
For example, when a light receiving element and a light emitting element are mounted on one circuit board, transmission and reception of an optical signal can be performed via an optical path conversion module.

In addition, when the light receiving element and the light emitting element are mounted in this way, it may have a configuration provided with an optical pin connector corresponding to each, or an optical pin provided with a multi-core optical pin One connector may be provided, and some of the optical pins may correspond to light receiving elements, and the remaining optical pins may correspond to light emitting elements.
As a specific example of the latter, for example, as an optical pin connector, as shown in FIG. 3-3, an optical pin connector 40 in which a plurality of optical pins 10 arranged in parallel are stacked in two stages is used. Examples include a configuration in which the optical pins 10e to 10h belonging to the lower stage correspond to the light receiving elements, and the optical pins 10a to 10d belonging to the upper stage correspond to the light emitting elements.

The interposer 110 constituting the optical path conversion module 100 is not necessarily provided, but may be provided as necessary. For example, a box-shaped interposer such as the interposer 110 (FIG. 4A). 4-2 (a)), the optical element and the driving integrated circuit can be protected without resin sealing, and there is a risk of contact with the optical element or the like when the optical pin connector is attached. It can be avoided. Therefore, by attaching the optical pin connector via the interposer, the optical pin connector can be easily attached and detached.

Further, in the optical path conversion module 100, a gap is formed inside the interposer 110. However, this portion may remain as it is, for example, at a communication wavelength that does not hinder transmission of an optical signal. On the other hand, it may be filled with a transparent resin or the like.
Further, in the optical path conversion module 100, no conductor circuit or the like is particularly formed in the interposer 110, but a conductor circuit or a pad may be formed in the interposer as necessary. This is because the interposer side can be connected to other circuit boards, optical components, and electronic components.
The material of the interposer is not particularly limited, and examples thereof include resin and ceramic.

The lens array 111 constituting the optical path conversion module is not necessarily provided, and may be provided as necessary. However, by providing the lens array 111, the spread of the transmission light can be suppressed or the transmission light can be reduced. Since it can be condensed, an optical signal can be transmitted more reliably.

The material of the lens array is not particularly limited, and examples thereof include those usually used for optical lenses. Specific examples thereof include optical glass and optical lens resins.
The resin for optical lenses is not particularly limited as long as it absorbs less in the communication wavelength band. For example, a part of a thermosetting resin, a thermoplastic resin, a photosensitive resin, or a thermosetting resin may be used. Examples include sensitized resins.
Specifically, for example, acrylic resins such as PMMA (polymethyl methacrylate), deuterated PMMA, deuterated fluorinated PMMA; polyimide resins such as fluorinated polyimide; epoxy resins; UV curable epoxy resins; Examples thereof include silicone resins such as resins; polymers produced from benzocyclobutene.

The lens array may include particles such as resin particles, inorganic particles, and metal particles.
By including particles, the strength of the lens array is improved and the shape is more reliably maintained, and the coefficient of thermal expansion is matched with the connector body constituting the interposer and optical pin connector. This is because misalignment or the like due to the difference in thermal expansion coefficient is less likely to occur.

When the lens array includes particles, it is desirable that the refractive index of the lens array body and the refractive index of the particles be approximately the same. Therefore, it is desirable that the particles included in the lens array are obtained by mixing two or more kinds of particles having different refractive indexes so that the refractive index of the particles is approximately the same as the refractive index of the resin component.
Specifically, for example, when the main body of the lens array is an epoxy resin having a refractive index of 1.53, the particles include silica particles having a refractive index of 1.46 and titania particles having a refractive index of 2.65. It is desirable to mix and dissolve to form particles.
Examples of the method of mixing the particles include a kneading method, a method of dissolving two or more types of particles and mixing them, and then forming particles.

The refractive index of the lens array is not particularly limited, and may be appropriately selected in consideration of the design of the optical path conversion module. Specifically, for example, when the refractive index of the lens array is the same as the refractive index of the core of the optical fiber constituting the optical pin connector, reflection of light at the interface between the two can be avoided. .

As a method for producing the lens array, when the material of the lens is glass or quartz, for example, anisotropic etching or photolithography can be used, and when the material of the lens is resin, For example, a method in which a material resin is poured into a mold and heat and a load are applied can be used.
In addition, the lens may be formed by dropping uncured resin onto a plate-like body made of glass, quartz, resin, or the like with a dispenser or the like, and then curing the dropped resin.
Further, it is necessary to form a guide hole in the lens array. However, the guide hole may be formed simultaneously with the formation of the lens or after the lens is formed.

FIG. 5 is a cross-sectional view schematically showing another example of the optical path conversion module according to the embodiment of the present invention.
The optical path conversion module 200 shown in FIG. 5 has no lens array, and the first light input / output surface 12 of the optical pin 10 constituting the optical pin connector 30 faces the optical element 202. Except for the extension, it is the same as the configuration of the optical path conversion module 100 shown in FIGS. Here, description of other components is omitted.
In FIG. 5, the last two digits of the reference numeral or the last two digits of the reference numeral and the alphabet are the same as those in FIGS.
Such an optical path conversion module 200 also has a function as an optical path conversion module of the present invention (a function of transmitting and receiving an optical signal and converting an optical path of an optical signal), and the optical path conversion of the present invention described above. The effect of the module for use can be enjoyed.

The optical path conversion module according to the embodiment of the present invention is not limited to the modules shown in FIGS. 4-1, 2 and 5 and may have, for example, the configuration described below.
FIG. 6 is a cross-sectional view schematically showing another example of the optical path conversion module according to the embodiment of the present invention.
As shown in FIG. 6, the optical path conversion module 300 includes an optical element 302 and a driving integrated circuit 303, the optical pin connector 30 according to the second embodiment described above, a conductor circuit 301b, and an insulating layer 301a. The circuit board 301 is provided.
The circuit board 301 is a circuit board 301 having a concave shape at the center, and an optical element 302 is mounted by solder bumps 304 and a driving integrated circuit 303 is mounted by wire bonding 305 in the recess. In the figure, reference numeral 303a denotes a die pad.

An interposer 310 is attached to the central portion of the circuit board 301 so as to close the concave portion, and a lens array 311 is fixed to the inner side (the concave portion side) of the interposer 310. Further, the optical pin connector 30 is attached to the interposer 310.
Here, the optical pin connector 30 includes two guide pins (not shown) like the optical path changing module 100 shown in FIG. 4A, and also includes a circuit board 301, a lens array 311 and Each of the interposers 310 includes guide holes (not shown) at two locations, and the guide pins are formed in guide holes (not shown) provided in each of the interposer 310, the lens array 311 and the circuit board 301. It is inserted in order. Therefore, the interposer 310, the lens array 311 and the circuit board 301 are aligned by the guide pins, and the optical elements mounted on the circuit board 301 constitute the optical pin connector 30 via the lens 311a. Optical signals can be transmitted to and from the optical pin 10.

Further, in the optical path conversion module 300, a solder resist layer 308 and solder bumps 309 are formed in the vicinity of the outer periphery of the circuit board 301 on the side provided with the interposer 310.
Therefore, the optical path conversion module 300 can be connected to an external substrate such as a motherboard substrate on the side where the optical pin connector is attached (see FIG. 7 below).
Also in the optical path conversion module 300 having such a configuration, the functions and effects of the optical path conversion module of the present invention described above can be enjoyed.

FIG. 7 is a cross-sectional view showing an example of an aspect in which the optical path changing module according to the embodiment of the present invention is mounted on a motherboard.
In the embodiment shown in FIG. 7, the optical path conversion module 300 is mounted via a solder bump 509 on a motherboard 500 having an optical waveguide formed therein.
The motherboard 500 is formed by laminating an insulating layer 501a and a conductor circuit 501b to form a circuit board 501, and an optical waveguide 520 including a core portion 520a and a cladding portion 520b is formed therein, and one outermost layer is formed. A solder resist layer 508 and solder bumps 509 are formed. In the figure, reference numeral 501c denotes a through hole.
In addition, a bottom hole 530 for the optical path is formed in the mother board 500 so that the inner end of the optical waveguide 520 is exposed.

When the optical path conversion module 300 is mounted on such a motherboard 500, the optical pins 10 of the optical pin connector 30 constituting the optical path conversion module 300 are inserted into the optical path bottomed hole 530. In addition, an optical path conversion module is mounted.
Here, by inserting the optical pin 10 so that the second light output surface 15 of the optical pin 10 and the core 520a of the optical waveguide 520 face each other, the optical element 302 and the motherboard constituting the optical path conversion module 300 An optical signal can be transmitted between the optical waveguide 520 formed on the substrate 500 and the optical pin connector 30 (optical pin 10).
At this time, the bottom of the optical path bottom hole 530 may be filled with matching oil. This is because the transmission loss between the optical pin and the optical waveguide can be further reduced by filling the matching oil.
In addition, instead of the bottomed hole for the optical path, an optical path through hole that penetrates the entire motherboard substrate may be formed in the motherboard for the motherboard.
In the mother board 500, the optical waveguide is formed only in a part of the inner layer, but the entire inner layer may be formed of the optical waveguide.

Further, when the optical path conversion module 300 is mounted in such a manner, the guide pins 39 included in the optical path conversion module are inserted through the connector main body 31 of the optical pin connector 30 (on the circuit board 301 side of the connector main body 31). If the guide hole is formed in the motherboard substrate, the guide pin can be inserted into the guide hole to change the optical path. The module and the motherboard substrate can be aligned.
As a matter of course, the embodiment of the present invention is not limited to the embodiment shown in FIG. 7 and can be implemented in various other modes.

FIG. 8 is a cross-sectional view schematically showing another example of the optical path conversion module according to the embodiment of the present invention.
The optical path changing module 400 shown in FIG. 8 has the same configuration as the optical path changing module 300 shown in FIG. 6 except for the connection terminals to the external substrate and the like.
That is, in the optical path conversion module 300, solder bumps 309 are formed on the circuit board 301 (BGA structure), whereas in the optical path conversion module 400, electric pins 409 are formed on the circuit board 401 instead of the solder bumps. (PGA structure).
Even the optical path conversion module 400 having such a structure can enjoy the functions and effects of the optical path conversion module of the present invention.
Since the optical path conversion module 400 is the same as the optical path conversion module 300 except for the external connection terminals, the description thereof is omitted. In FIG. 8, the last two digits of the reference numeral or the last two digits of the reference numeral and the alphabet are the same as those in FIG.

Next, a method for manufacturing the optical path conversion module according to the embodiment of the present invention will be briefly described.
First, a circuit board is manufactured using methods such as a subtractive method, a full additive method, a semi-additive method, a batch formation method, and a conformal method.
Thereafter, a guide hole is formed at a predetermined position by drilling or laser processing based on the recognition mark formed on the circuit board.
Next, an optical element and a driving integrated circuit are mounted on the circuit board. Here, a mounting method such as wire bonding or flip chip bonding can be used as the mounting method.

Next, an interposer having guide holes formed at predetermined positions is prepared, and the interposer is attached to the circuit board with reference to a recognition mark formed on the circuit board.
Further, when an optical path conversion module including a lens array is manufactured, the lens array in which the guide holes are formed is fixed to the interposer before the interposer is attached to the circuit board. In this case, the lens array is attached so that the guide hole of the interposer and the guide hole of the lens array are just in communication.

Finally, the optical pin connector to which the guide pins are attached is attached so that the guide pins are inserted into the guide holes of the interposer, the lens array, and the circuit board. Complete.
In the optical path conversion module of the present invention, by inserting the guide pin and attaching the optical pin connector, the optical pin constituting the optical pin connector and the optical element mounted on the circuit board are aligned. .

The optical pin, the optical pin connector, and the optical path changing module of the present invention can be suitably used in the field of optical communication.

(A) is a side view of the optical pin which concerns on embodiment of this invention, (b) is a front view of the optical pin shown to (a), (c) is the AA line of (a). It is sectional drawing. (A)-(c) is the schematic diagram which showed the process of manufacturing the optical pin which concerns on embodiment of this invention. (A) is a perspective view which shows an example of the optical pin connector which concerns on embodiment of this invention, (b) is a front view of the optical pin connector shown to (a), (c) is ( It is a top view of the optical pin connector shown to a). (D) is a BB line sectional view of Drawing 3-1 (a), and (e) is a perspective view showing only a connector main part which constitutes an optical pin connector shown in (a). (A) is a perspective view which shows typically another example of the optical pin connector which concerns on embodiment of this invention, (b) is CC sectional view taken on the line of (a). (A) is sectional drawing which shows typically an example of the module for optical path conversion which concerns on embodiment of this invention, (b) is the DD sectional view taken on the line of (a). (C) is the fragmentary perspective view of the interposer which comprises the module for optical path conversion shown to Fig.4-1 (a), (d) is the module for optical path conversion shown to Fig.4-1 (a) It is a perspective view of the lens array which comprises. It is sectional drawing which shows typically another example of the module for optical path conversion which concerns on embodiment of this invention. It is sectional drawing which shows typically another example of the module for optical path conversion which concerns on embodiment of this invention. It is sectional drawing which shows an example of the aspect which mounted the optical path conversion module which concerns on embodiment of this invention in the board | substrate for motherboards. It is sectional drawing which shows typically another example of the module for optical path conversion which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical pin 11 Optical fiber 12 1st light input / output surface 13 Light reflection surface 14 Metal layer 15 2nd light input / output surface 30, 40 Optical pin connector 31, 41 Connector main body 32, 42 Adhesive 33, 43 Through-hole 34, 44 Slit unit 100, 200, 300, 400 Optical path conversion module 101, 201, 301, 401 Circuit board 102, 202, 302, 402 Optical element 103, 203, 303, 403 Drive integrated circuit 110, 210, 310, 410 Interposer 111, 311, 411 Lens array

Claims (4)

A first light input / output surface located at an end of an optical fiber having a core extending in the axial direction and a clad surrounding the core, a light reflecting surface located at the other end of the optical fiber, and the light reflecting surface And a metal layer that contacts the outer edge of the light reflecting surface and covers one side of the optical fiber, and a second layer that is adjacent to the other end of the optical fiber and exposes the optical fiber. An optical pin comprising: an optical input / output surface. An optical fiber having an axially extending core and a clad surrounding the core, and transmitting an optical signal; a first optical input / output surface positioned at an end of the optical fiber for inputting / outputting an optical signal; A light reflecting surface that is located at the other end of the optical fiber facing the first light input / output surface and changes an optical path angle of an optical signal to 90 degrees, covers the light reflecting surface, and the light reflecting surface A metal layer that contacts the outer edge of the optical fiber and covers one side surface of the optical fiber; and a second layer that inputs and outputs an optical signal from the exposed side surface of the optical fiber adjacent to the other end portion of the optical fiber. An optical pin comprising an optical input / output surface. A first light input / output surface located at an end of an optical fiber having a core extending in the axial direction and a clad surrounding the core, a light reflecting surface located at the other end of the optical fiber, and the light reflecting surface And a metal layer that contacts the outer edge of the light reflecting surface and covers one side of the optical fiber, and a second layer that is adjacent to the other end of the optical fiber and exposes the optical fiber. An optical pin having a light input / output surface of
A plurality of through-holes corresponding to the plurality of optical pins arranged in parallel in the axial direction, and a slit portion that crosses the through-holes in a direction perpendicular to the axial direction; A connector body to be inserted into,
An adhesive that fills the slit portion and fixes the optical pin to the connector body;
An optical pin connector comprising: A first light input / output surface located at an end of an optical fiber having a core extending in the axial direction and a clad surrounding the core, a light reflecting surface located at the other end of the optical fiber, and the light reflecting surface And a metal layer that contacts the outer edge of the light reflecting surface and covers one side of the optical fiber, and a second layer that is adjacent to the other end of the optical fiber and exposes the optical fiber. An optical pin having a light input / output surface of
An optical element that emits or receives an optical signal to the optical pin;
A driving integrated circuit electrically connected to and driving the optical element;
A plurality of through-holes corresponding to the plurality of optical pins arranged in parallel in the axial direction, a slit portion that crosses the through-holes in a direction perpendicular to the axial direction, and the optical pins are inserted into the through-holes. An optical pin connector that has a plurality of guide pins adjacent to the connector main body and the row of the through holes, protrudes from the connector main body, is filled with an adhesive in the slit portion, and fixes the optical pin to the connector main body; ,
A guide hole provided corresponding to each of the plurality of guide pins; the optical element and the driving integrated circuit are mounted; the guide pin is inserted into the guide hole; A circuit board for optical signal transmission positioning,
An optical path conversion module comprising:

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