JP2009122197A - Positioning structure of optical connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positioning structure of an optical connector, a structure which can secure fixed positioning accuracy and which can be manufactured at low cost. <P>SOLUTION: As a means for mutually positioning an optical connector 1 and an optical component 2 to be connected thereto, there are formed engaging receiving grooves 11a, 11b, in one of the connecting face 1a of the optical connector 1 or the connecting face 2a of the optical component 2, and engaging projected lines 7a, 7b that fit in the engaging receiving grooves, in the other. The illustrated examples are that the optical component 2 is a circuit substrate 2 loaded with an optical element and that the optical connector 1 is a surface mounting type optical connector which converts an internal optical fiber optical path parallel with the substrate 2 toward the optical element on the substrate face 2a by means of a mirror 16a. The positioning structure by the engagement of the grooves with the projected lines, compared to a positioning structure by the engagement of circular pins with pin holes, facilitates increased accuracy in resin forming and also enables a highly accurate metallic mold to be manufactured at a low cost. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical connector positioning structure that constitutes means for positioning an optical connector and an optical component connected to the optical connector.

For example, there is a fitting pin positioning method as a positioning means between optical connectors. This fitting pin positioning method is a positioning method adopted for a so-called MT optical connector (generally equivalent to an F12 type multi-core optical fiber connector defined in JIS C 5981). Pin holes are made on both sides of the hole arrangement direction. Then, the fitting pins are passed through the pin holes of the opposing optical connectors in the pin holes on both sides, and the opposing optical connectors are positioned (axis alignment between the optical fibers).
Multi-fiber optical connector and method for assembling the same

In the fitting pin positioning type optical connector described above, the tolerance of the pin hole diameter is extremely small, and the clearance with respect to the outer diameter of the SUS fitting pin is extremely small.
Therefore, if the mold accuracy is lowered or the manufacturing process is changed in order to reduce the manufacturing cost, the accuracy of the pitch of the two pin holes on both the left and right sides of the optical fiber hole row will be lowered, and the light facing the fitting pin will be reduced. Even if it tries to penetrate the pin hole of the connector, it may not be easily inserted.
Alternatively, even if the fitting pin can be bridged, the positioning accuracy of the optical fiber hole may be poor.

  To prevent the situation where the fitting pin does not enter the pin hole of the mating optical connector, or to maintain the positioning accuracy of the optical fiber, maintain the accuracy of the hole diameter and the hole position for each of the two pin holes. As a result, there is a problem that the manufacturing cost of the optical connector cannot be reduced.

In the above description, the optical connection between the optical connectors has been described. For example, when the optical connector is accurately positioned and attached to a predetermined position on a substrate (a photoelectric composite substrate in which an optical element and an electronic element are mixed), The same can be said for the above. That is, the optical connector in this case is a surface mount type optical connector in which an optical fiber is fixed in an optical fiber hole provided in parallel with the substrate, and the optical fiber optical path is changed toward an optical element on the substrate by a mirror. A fitting pin provided perpendicular to the substrate surface is fitted into a pin hole on the substrate side for positioning, but there is a problem similar to the above.
Furthermore, in this case, it is necessary to embed a metal fitting pin in the optical connector main body during resin molding of the optical connector main body, or to insert and insert the fitting pin into a hole formed in the optical connector main body. Embedding pins in the resin molded body (optical connector main body) as in the former is not preferable in terms of product accuracy and manufacturing cost. When the pin insertion and pin assembly processes are separated as in the latter case, the product cost increases.

  The present invention has been made in view of the above circumstances, and as a positioning means for the optical component on the connection partner side, it is possible to ensure a desired positioning accuracy without requiring a particularly high molding accuracy, and an optical device. An object of the present invention is to provide an optical connector positioning structure that enables inexpensive manufacturing of the connector.

  The present invention for solving the above-mentioned problems is an optical connector positioning structure, and as means for positioning an optical connector and an optical component connected to the optical connector, the connection surface of the optical connector or the connection surface of the optical component is provided. A fitting receiving groove is formed on one side, and a fitting protrusion that fits in the fitting receiving groove is formed on the other side.

  A second aspect of the present invention is the optical connector positioning structure of the first aspect, wherein at least one of the optical components is an optical connector.

  According to a third aspect of the present invention, in the optical connector positioning structure of the first aspect, the optical component is a substrate on which an optical element is mounted. It is a surface-mounting type optical connector that changes toward the surface.

  Claim 4 includes at least a pair of linear fitting portions each including a fitting receiving groove and a fitting projection in the optical connector positioning structure according to any one of claims 1 to 3, and the pair of wires The direction of the shape fitting part is different from each other.

  According to a fifth aspect of the present invention, in the optical connector positioning structure of the fourth aspect, the directions of the pair of linear fitting portions are orthogonal to each other.

  According to a sixth aspect of the present invention, in the optical connector positioning structure of the fourth aspect, one of the pair of linear fitting portions is at one corner of the rectangular connection surface of the optical connector and the other is the rectangular connection surface of the optical connector. It is provided so that it may each be located in the other corner part of this.

In the present invention, the optical connector and the optical component are positioned by fitting the connection surface of the optical connector and one groove (fitting receiving groove) of the connection surface of the optical component with the other protrusion (fitting protrusion). Is done. For example, a positioning structure by fitting a groove such as a V-groove and a ridge has a problem that the clearance needs to be sufficiently small in order to increase accuracy compared to a positioning structure by fitting a circular pin and a pin hole. Therefore, it is easy to increase accuracy.
Also, for molds with integral resin molding, molds with straight parts such as grooves or ridges are easier and less expensive than molds that form circular holes or pins. Can be manufactured. In particular, a mold that forms a circular pin hole has a complicated and expensive structure for supporting the pin core for the pin hole, and it is necessary to accurately maintain the position of the rod core. There is a problem that resin leakage and burrs are more likely to occur than the joints of the mold. Therefore, it is difficult to significantly reduce the manufacturing cost of the optical connector.
On the other hand, in the case of the groove / projection fitting structure as in the present invention, since the main element that determines the positioning accuracy is a mold mainly composed of only a straight line, those defects do not occur. .
When the present invention is applied to a surface mount type optical connector as in claim 3, the above-described effects are effectively exhibited.

  As in claim 4, when at least a pair of linear fitting portions each formed of a fitting receiving groove and a fitting protrusion are provided and the directions of the pair of linear fitting portions are different from each other, the pair of linear shapes The positioning on the plane can be performed completely by the fitting portion.

  According to the fifth aspect, the configuration in which the pair of linear fitting portions are orthogonal to each other facilitates positioning in two orthogonal directions on a plane.

  As in claim 6, even if one of the pair of linear fitting portions is provided at one corner of the rectangular connecting surface of the optical connector and the other is provided at the other corner, the two orthogonal fitting directions on the plane can be obtained. Positioning can be performed. Further, in this case, positioning can be performed with short grooves or ridges, and the optical molding of the optical connector and the optical component is simplified.

  Hereinafter, an optical connector positioning structure embodying the present invention will be described with reference to the drawings.

  FIG. 1 shows an optical connector positioning structure according to an embodiment of the present invention, and is a perspective view showing an optical connector 1 and a circuit board (optical component) 2 on which the optical connector 1 is mounted. 2 is a plan view of the optical connector 1 viewed from the lower surface side of FIG. 1, and FIG. 3 is a plan view of the circuit board 2 viewed from the upper surface of FIG. 4 is a plan view of the optical connector 1 mounted on the circuit board 2, and FIG. 5 is a cross-sectional view taken along line AA of FIG.

The circuit board 2 of the present embodiment has a U-shaped cross section in which the space between the thick side portions 2b is a thin bottom portion 2a, and the bottom portion 2a is a substrate surface 2a that is also a connection surface with the optical connector 1. As shown in FIGS. 3 and 5, the circuit board 2 has a plurality of optical elements (light emitting elements or light receiving elements) 5 aligned on the board surface 2a corresponding to the optical fiber 17 on the optical connector 1 side. It is a mounted optical module. An optical element array including a plurality of aligned optical elements 5 is also denoted by the same reference numeral 5.
Two fitting ridges 7a and 7b that are orthogonal to each other are formed on a board surface 2a that is a connection surface on the circuit board 2 side. The fitting protrusions 7a and 7b in the illustrated example are Λ-shaped protrusions (or inverted V-shaped protrusions). One of the fitting ridges 7a is provided outside the optical element row 5 (on the left side in FIG. 3 (on the side opposite to the optical fiber introduction side)) in parallel with the optical element row 5, and the other fitting ridge 7b. Is provided at one end side in the arrangement direction of the optical element rows 5 and orthogonal to the one fitting protrusion 7a.

The optical connector 1 is a surface-mount type light that is molded with a thermoplastic resin such as PPS, for example, by changing the internal optical fiber optical path parallel to the board surface 2a of the circuit board 2 toward the optical element on the board by a mirror. It is a connector.
A detailed structure of the optical connector 1 will be described. Reference numeral 15 denotes an optical fiber insertion hole formed in parallel with the connection surface 1a and penetrating through the optical connector. One end of the optical fiber insertion hole 15 opens into the notch 1b at the lower end of the optical connector, and the other end opens into the recess 16.
In FIG. 5, a plurality of optical fiber insertion holes 15 are arranged at equal pitches in a direction perpendicular to the paper surface (aligned vertically in FIG. 2).
The bare optical fiber 17 from which the tip coating has been removed is inserted from the cutout portion 1b and bonded and fixed inside the optical connector.
The recess 16 has a substantially triangular cross section when viewed from the direction perpendicular to the plane of FIG.
The tip of the optical fiber 17 inserted into the recess 16 protrudes somewhat in the recess 16.
The opposite side 16a of the recess 16 facing the optical fiber 17 is an inclined surface inclined by 45 ° with respect to the direction perpendicular to the paper surface. The surface of the optical connector resin in this portion becomes a mirror surface by metal plating of silver or the like. ing.
When the optical connector 1 is positioned on the circuit board 2, the optical axis of the optical element 5 and the optical axis of the light propagating through the optical fiber 17 are orthogonal to each other by the mirror surface 16 a as an optical path changing structure.
When the optical element 5 is a light receiving element, the light emitted from one optical fiber 17 is reflected by the mirror surface 16a and turned at a right angle, and enters the optical element 5 at a predetermined position on the substrate surface 2a. Optically connected (optical coupling).
When the optical element 5 is a light emitting element, it is optically coupled by entering the optical fiber 17 through the reverse optical path.
The top of the recess 16 is sealed with an optical adhesive using transparent glass.
The tip of the optical fiber protruding into the recess 16 is sealed with an optical adhesive and fixed in the recess 16.

Two fitting receiving grooves 11a and 11b which are orthogonal to each other are formed on a connection surface (surface having a light input / output portion) 1a of the optical connector 1. The fitting receiving grooves 11a and 11b in the illustrated example are V grooves. The shape of the fitting receiving groove may be an inverted trapezoidal groove formed by horizontally cutting a V-shaped sharp tip. Further, the groove is not limited to the V shape, and may be a groove having another cross-sectional shape such as a U shape. The fitting protrusion on the circuit board 2 side has a cross-sectional shape corresponding to the cross-sectional shape of the fitting receiving groove of the optical connector 1.
The two fitting receiving grooves 11a and 11b on the optical connector 1 side and the two fitting protrusions 7a and 7b on the circuit board 2 side are fitted to each other when the optical connector 1 is attached to the circuit board 2. Are in a mutual positional relationship. That is, the fitting ridge 7a is fitted into the fitting receiving groove 11a, and the fitting ridge 7b is fitted into the fitting receiving groove 11b.
Reference numeral 12a denotes a linear fitting portion formed by the fitting protrusion 7a and the fitting receiving groove 11a, and reference numeral 12b denotes a linear fitting portion formed from the fitting protrusion 7b and the fitting receiving groove 11b. .
Positioning in two orthogonal directions on the plane is performed by the two orthogonal linear fitting portions 12a and 12b, and the optical connector 1 and the circuit board 2 are completely positioned on the board surface. At this time, a plurality of optical elements (light receiving elements or light emitting elements) 5 arranged on the surface of the substrate surface 2a and a plurality of optical fibers 17 attached to the optical connector 1 are optically connected.

As described above, the mutual positioning of the optical connector 1 and the circuit board 2 is formed in the grooves (fitting receiving grooves) 11a and 11b formed in the connection surface 1a of the optical connector 1 and the connection surface 2a of the circuit board 2. It is performed by fitting with a ridge (fitting ridge). The positioning structure by fitting the groove and the ridge does not have the problem that the clearance needs to be sufficiently small to increase the accuracy compared to the positioning structure by fitting the circular pin and pin hole. Is easy to increase.
It is particularly easy to obtain high positioning accuracy if the V-grooves (fitting receiving grooves) 11a and 11b and the Λ-shaped ridges (fitting ridges) are fitted as in the illustrated example.
In addition, with regard to a mold for resin integral molding, a mold having a higher accuracy can be manufactured at a lower cost by using a mold for forming grooves or ridges than a mold for forming circular holes or circular pins.
In particular, a mold that forms a circular pin hole has a complicated and expensive structure for supporting the pin core for the pin hole, and it is necessary to accurately maintain the position of the rod core. There is a problem that resin leakage and burrs are more likely to occur than the joints of the mold. On the other hand, as described above, if the groove-projection fitting structure is used as in the present invention, those defects do not occur.
In the surface mount type optical connector, since the connection surface 1a with the counterpart optical component 2 is wide, it is easy to secure a space for providing grooves or ridges. Therefore, the present invention is suitable for application to a surface mount type optical connector. is there.
In contrast to the above-described embodiment, a fitting protrusion may be provided on the optical connector 1 side, and a fitting receiving groove in which the fitting protrusion is fitted may be provided on the circuit board 2 side.

FIG. 6 shows an optical connector positioning structure according to another embodiment of the present invention, and is a perspective view showing an optical connector 1 ′ and a circuit board 2 ′ on which the optical connector 1 ′ is mounted. FIG. 7 is a plan view of the optical connector 1 ′ viewed from the lower surface side of FIG.
In this embodiment, a pair of fitting receiving grooves 11a ′ and 11b ′ that are symmetrical in the shape of a letter C are formed at both corners of the connecting surface 1a ′ of the optical connector 1 ′. On the connection surface 2a ′ of the circuit board 2 ′, a pair of fitting ridges 7a ′ and 7b ′ that are symmetrical in the shape of a letter C are formed.
Reference numeral 12a 'denotes a linear fitting portion formed by the fitting protrusion 7a' and the fitting receiving groove 11a 'which are fitted together, and a linear fitting portion formed by the fitting protrusion 7b' and the fitting receiving groove 11b '. When indicated by reference numeral 12b ′, in this embodiment, one of the pair of linear fitting portions 12a ′ and 12b ′ is connected to one corner of the rectangular connecting surface of the optical connector, and the other is connected to the rectangular of the optical connector. It is provided so as to be located at the other corner of the surface. Portions common to the embodiment of FIGS. 1 to 5 are denoted by the same reference numerals and description thereof is omitted.
Positioning in two orthogonal directions on the plane can also be performed by the linear fitting portions 12a ′ and 12b ′ having a C-shaped arrangement as in this embodiment. In this case, positioning can be performed with short grooves or ridges, and the optical molding of the optical connector and the substrate can be simplified.
In addition, in order to enable complete positioning on the board surface of the optical connector and the circuit board (positioning in two orthogonal directions), the direction of the pair of linear fitting portions may be orthogonal to each other, The present invention is not limited to the arrangement, and it is only necessary that the directions of the pair of linear fitting portions are different from each other, so that various modifications are possible.

8 is a perspective view showing an optical connector positioning structure of still another embodiment of the present invention, showing an optical connector 1 ″ and a circuit board 2 ″ on which the optical connector 1 ″ is mounted. FIG. 9 is a plan view of the optical connector 1 ″ viewed from the lower surface side in FIG.
In this embodiment, a pair of fitting receiving grooves 11a "and 11b" parallel to each other are formed on both sides of the rectangular connection surface 1a "of the optical connector 1", and the circuit board 2 "is connected correspondingly. A pair of fitting ridges 7a "and 7b" are formed parallel to the surface 2a ".
Reference numerals 12a "denote linear fitting portions formed by fitting convex strips 7a" and fitting receiving grooves 11a ", and linear fitting portions formed from fitting convex strips 7b" and fitting receiving grooves 11b ". Is denoted by reference numeral 12b ″. Portions common to the embodiment of FIGS. 1 to 5 are denoted by the same reference numerals and description thereof is omitted.
In this optical connector positioning structure, the optical connector 1 ″ and the circuit board 2 ″ can be positioned in the optical fiber alignment direction (vertical direction in FIG. 9) by the linear fitting portions 12a ″ and 12b ″. In this case, mutual positioning in the longitudinal direction of the optical fiber (left-right direction in FIG. 9) is provided separately. The number of linear fitting portions for positioning in the optical fiber alignment direction is not necessarily two as shown in the figure, and may be one.

FIG. 10 is a perspective view showing a positioning structure of the optical connector when the optical component connected to the optical connector is also an optical connector, that is, when applied to optical connection between the optical connectors.
In this case, the two optical connectors 21 and 21 'are so-called MT optical connectors (generally equivalent to F12 type multi-core optical fiber connectors defined in JIS C 5981), and a positioning method using their fitting pins and fitting pin holes. Instead of this, a positioning method using a fitting receiving groove and a fitting protrusion formed on the connection surface is adopted.
In the illustrated example, fitting receiving grooves 31a and 31b in two perpendicular directions are formed on the connection surface 21a of one optical connector 21, and the fitting receiving grooves 31a and 31b are formed on the connecting surface 21a 'of the other optical connector 21'. Fitting protrusions 27a and 27b in two orthogonal directions to be fitted are formed.
Each optical connector 21, 21 ′ has an opening 24 for inserting an optical fiber tape core wire on the same one end side of a substantially rectangular connector body 23 having a flange portion 22 on one end side. It is a hollow portion, and an adhesive filling window (not shown) that communicates with the hollow portion is opened on either the upper or lower surface of the optical connectors 21 and 21 ′. A portion other than the hollow portion is a resin-filled portion, and an optical fiber hole 25 along the optical connector connection direction (optical fiber insertion direction) passes through the resin-filled portion.

When the two optical connectors 21 and 21 ′ are optically connected, the connection surfaces 21a and 21a ′ are attached to each other. At that time, the fitting protrusions 27a and 27b of one optical connector 21 ′ are connected to the other light. The connector 21 is fitted into the fitting receiving grooves 31a and 31b. As a result, positioning in two perpendicular directions on the connection surfaces 21a and 21a ′ between the two optical connectors 21 and 21 ′ is completely performed.
Even in this optical connector positioning structure, there is no problem that the clearance needs to be sufficiently small in order to increase the accuracy compared to the positioning structure by fitting the circular pin and the pin hole. The effect that it is easy, and the effect similar to the case where it applies to the surface mount type optical connector mentioned above are acquired.

The optical connector positioning structure of this embodiment can be positioned on the connection surfaces 21a and 21a 'itself of both optical connectors 21 and 21', but the optical connectors 21 and 21 'do not tilt and form a straight line. It is not enough to face each other.
Accordingly, an angle is likely to be generated between the optical connectors 21 and 21 ', but the linearity of the optical connectors 21 and 21' when the connectors are connected is, for example, a clamp spring for clamping the optical connectors 21 and 21 ', or both It is conceivable to secure the optical connectors 21 and 21 ′ with cylindrical adapters or the like that fit the tip portions of the optical connectors 21 and 21 ′ in a facing state.

The circuit board 2 in FIGS. 1 to 9 is an optical module (optical block) having a U-shaped cross section. The optical module is disposed at an appropriate position on a circuit pattern on which a flat circuit circuit board (not shown) is formed. Light receiving and emitting elements are disposed on the substrate surface 2a of the optical module, and the optical axes of these light emitting and receiving elements are directed from the substrate surface 2a in the vertical direction.
As the optical fiber used in the present invention, for example, a silica-based optical fiber having a diameter of 125 μm or a silica-based optical fiber having a smaller diameter can be used. Further, it is possible to adopt a transmission mode of SM type or GI type.
Further, in order to mechanically stabilize the positioning connection state, an appropriate positioning structure can be provided separately from the fitting portion.

The optical connector positioning structure of one Example of this invention is shown, and it is a perspective view which shows the optical connector and the circuit board (optical component) in which this optical connector is mounted. It is the top view which looked at the optical connector in FIG. 1 from the lower surface side of FIG. It is the top view which looked at the circuit board in FIG. 1 from the upper surface of FIG. It is a top view of the state which mounted the optical connector in the circuit board. It is AA sectional drawing of FIG. The optical connector positioning structure of the other Example of this invention is shown, It is a perspective view which shows the optical connector and the circuit board by which this optical connector is mounted. It is the top view which looked at the optical connector in FIG. 6 from the lower surface side of FIG. The optical connector positioning structure of the further another Example of this invention is shown, It is a perspective view which shows the optical connector and the circuit board by which this optical connector is mounted. It is the top view which looked at the optical connector in FIG. 8 from the lower surface side of FIG. It is a perspective view which shows the positioning structure of the optical connector of an Example in case an optical component is an optical connector.

Explanation of symbols

1, 1 ', 1 "optical connector 1a, 1a', 1a" connection surface 2, 2 ', 2 "circuit board (optical component)
2a, 2a ', 2a "substrate surface (connection surface)
7a, 7b, 7a ′, 7b ′, 7a ″, 7b ″, fitting projections 11a, 11b, 11a ′, 11b ′, 11a ″, 11b ″ fitting receiving grooves 12a, 12b, 12a ′, 12b ′, 12a ", 12b" Linear fitting part 15 Optical fiber hole 16 Recess 16a Mirror 17 Optical fiber 21, 21 'Optical connector 21a, 21a' Connection surface 27a, 27b Fitting protrusion 31a, 31b Fitting receiving groove

Claims (6)

  As means for positioning one optical component and the other optical component relative to each other, at least one fitting receiving groove on the connection surface of one optical component and at least one fitting to the fitting receiving groove on the other optical component The one optical component and the other optical component are positioned by forming the fitting convex strip at the location, and the fitting convex strip is fitted in the fitting receiving groove, and the optical path carried by the one optical component An optical connector positioning structure in which an optical path carried by the other optical component is connected.   2. The optical connector positioning structure according to claim 1, wherein at least one of the optical components is an optical connector.   The optical component is a substrate on which an optical element is mounted, and the optical connector is a surface mount optical connector that changes an optical fiber optical path parallel to the substrate toward the optical element on the substrate by a mirror. The optical connector positioning structure according to claim 1.   4. The apparatus according to claim 1, wherein at least a pair of linear fitting portions each including the fitting receiving groove and the fitting protrusion are provided, and the directions of the pair of linear fitting portions are different from each other. 2. An optical connector positioning structure according to 1.   The optical connector positioning structure according to claim 4, wherein directions of the pair of linear fitting portions are orthogonal to each other.   One of the pair of linear fitting portions is provided at one corner of the rectangular connection surface of the optical connector, and the other is disposed at the other corner of the rectangular connection surface of the optical connector. 5. The optical connector positioning structure according to claim 4, wherein:

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