JP2010002931A - Optical connector adapter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique by which an optical filter is easily built in an optical path, in a technique of utilizing an optical filter for the purpose of identifying a large number of optical fibers such as identification of subscriber terminals in an optical fiber communication network. <P>SOLUTION: An optical connector adapter is disclosed which includes a connector receiving part 1A to which an optical connector 6 is inserted, and a plug part 1B which is insertable to a receiving side optical connector 7. Further, the optical connector adapter is constituted by incorporating a ferrule 8 with a built-in grating, the ferrule to which an optical fiber grating 82 is inserted and fixed. Through the optical fiber grating 82, there are optically connected, a ferrule 61 of the optical connector 6 which is inserted to the connector receiving part 1A, and a ferrule 74 assembled in the receiving side optical connector 7 to which the plug part 1B is inserted, by being abutted from both sides in the ferrule 8 with a built-in grating. In the ferrule 8 with a built-in grating, there is installed a cladding mode beam absorbing means that absorbs a cladding mode beam. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical connector with an optical filter, and more particularly to an optical connector adapter with an optical filter.

For example, in FTTH (Fiber To The Home), a dielectric multilayer filter or an optical fiber grating (hereinafter also referred to as FBG) is used as a subscriber terminal for user identification. An optical connector (mainly SC type optical connector) incorporated in a ferrule is employed (for example, Patent Document 1).
Each of the dielectric multilayer filter and the FBG functions as an optical filter that determines wavelength selectivity of an optical fiber incorporated in the ferrule, such as a transmission wavelength, a cutoff wavelength, and a reflection wavelength.
The former ferrule incorporating a dielectric multilayer filter is obtained by inserting a dielectric multilayer film filter into an oblique groove cut into the ferrule and bonding and fixing it.
The ferrule incorporating the latter FBG (hereinafter also referred to as FBG filter) as an optical filter uses an optical fiber with a grating formed at the tip, and the tip of this optical fiber is inserted into a fine hole of the ferrule and bonded and fixed. It is common.
The optical connector includes a ferrule (optical filter) with an optical filter at the tip of a drop cable pulled from a trunk cable at a subscriber's home, regardless of whether the optical filter incorporated in the ferrule is a dielectric multilayer filter or FBG. There is an operation of connecting an optical fiber pigtail extending from a connector) by fusion splicing or the like.

Japanese Patent No. 3615924

However, the optical connector incorporating the ferrule with an optical filter described above has the following problems.
(1) If the filter characteristics are poor, the tip of the optical fiber must be cut and discarded.
(2) In the case of an FBG filter, the length of the FBG filter is related to the cutoff wavelength. Since the entire length of the SC ferrule is standardized, there is a case where an FBG filter having a necessary length for obtaining a desired cutoff wavelength cannot be accommodated in the ferrule. For this reason, in the case of the FBG filter, the cutoff wavelength may be restricted.

  In view of the above problems, the present invention can be easily inserted between an optical connector (optical connector plug) and a receiving-side optical connector to which the optical connector is inserted and connected. For the purpose of providing an optical connector adapter that allows an optical fiber grating inserted and fixed to a ferrule incorporated in a housing body to be easily inserted into an optical line by being inserted between the optical connector and the receiving optical connector. Yes.

In order to solve the above problems, the present invention provides the following configuration.
The invention according to claim 1 is a male housing part having a connector housing recess into which an optical connector is inserted, and a male housing insertable into a receiving side optical connector having a connector housing recess into which the optical connector is inserted. A ferrule with a built-in grating in which an optical fiber grating is inserted and fixed, and a ferrule of an optical connector inserted into the female housing part. The ferrule built into the receiving optical connector into which the male housing portion is inserted is abutted against the ferrule with a built-in grating from both sides, so that the optical fiber on the optical connector side and the receiving optical connector side An optical fiber in the ferrule with a built-in grating. Through is adapted to be optically connected to the the grating built within the ferrule, to provide an optical connector adapter cladding mode light absorbing means for absorbing cladding mode light of the optical fiber grating is provided.
The invention according to claim 2 is an adhesive with a light absorber provided so that the cladding mode light absorbing means covers an outer peripheral surface of the optical fiber grating housed in a fine hole penetrating the ferrule with a built-in grating. An optical connector adapter according to claim 1 is provided.
According to a third aspect of the present invention, there is provided a shielding body that has a light transmitting hole corresponding to a mode field diameter or a core diameter as the cladding mode light absorbing means in the ferrule with a built-in grating and shields the cladding mode light. The optical connector adapter according to claim 1, wherein the optical connector adapter is built-in.

  Since the optical connector adapter according to the present invention includes a connector receiving portion into which an optical connector (optical connector plug) is inserted and a plug portion that can be inserted into the receiving optical connector, the optical connector, the receiving optical connector, You can easily break in between. Then, the ferrule of the optical connector inserted into the connector receiving portion and the ferrule incorporated in the receiving optical connector into which the plug portion is inserted are abutted from both sides with the built-in grating ferrule incorporated in the housing body. Thus, an optical fiber grating in the ferrule with a built-in grating is interposed between the optical fiber inserted in the ferrule of the optical connector and the optical fiber inserted in the ferrule of the receiving optical connector. For example, desired wavelength selectivity such as a cutoff wavelength can be easily provided.

It is a figure which shows the relationship between the optical connector adapter of embodiment which concerns on this invention, the optical connector (optical connector plug), and the receiving side optical connector which inserts and fits this optical connector. It is the expanded sectional view which showed typically the structure of the optical connector adapter of FIG. 1 is an overall perspective view showing an optical connector adapter according to an embodiment of the present invention. (A)-(c) is a figure which shows the structure of an optical connector adapter. It is a front sectional view showing the internal structure of the optical connector adapter of the embodiment according to the present invention. (A), (b) is sectional drawing which shows the relationship between the housing main body of an optical connector adapter, and the plug frame main body integrated in the male housing part of this housing main body, (a) is before an assembly | attachment of a plug frame main body, (B) shows after incorporation. It is the perspective view which looked at the housing main body of the optical connector adapter from the female housing part side. It is the perspective view which looked at the housing main body from the male housing part side. It is a figure which shows the relationship between an optical connector adapter, the optical connector (optical connector plug), and the receiving side optical connector which inserts and fits this optical connector. It is a figure which shows the state which fitted and connected the optical connector to the receiving side optical connector. (A)-(c) is a figure which shows the components with a nail | claw integrated in the female side housing part of an optical connector adapter. (A), (b) is a figure which shows the ferrule and flange component integrated in an optical connector adapter. It is a figure which shows the state which fixed the optical fiber grating in the ferrule with the adhesive agent with a light absorber. It is a figure which shows the state which incorporated the shielding body which shields cladding mode light in a ferrule.

Hereinafter, an optical connector adapter embodying the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing the relationship between an optical connector adapter 1 according to an embodiment of the present invention, an optical connector 6 (optical connector plug), and a receiving optical connector 7 into which the optical connector 6 is inserted and fitted. 2 is an enlarged cross-sectional view schematically showing the structure of the optical connector adapter 1.
3 to 8 are diagrams showing specific configuration examples of the optical connector adapter 1, and FIG. 3 is an overall perspective view showing the optical connector adapter 1 of the embodiment according to the present invention, and FIG. FIGS. 6A and 6B are diagrams showing the structure of the optical connector adapter 1, and FIGS. 6A and 6B are a plug frame incorporated in the housing body 2 of the optical connector adapter 1 and the male housing portion 5 of the housing body 2. FIG. FIG. 7 is a perspective view of the housing body 2 of the optical connector adapter 1 seen from the female housing part 4 side, and FIG. 8 is a perspective view of the housing body 2 seen from the male housing part 5 side. FIG.
9 is a diagram showing the relationship between the optical connector adapter 1 illustrated in FIGS. 3 to 8, the optical connector 6 (optical connector plug), and the receiving optical connector 7 into which the optical connector 6 is inserted and fitted. It is.

As shown in FIGS. 1 and 2, an optical connector adapter 1 according to the present invention includes a connector receiving portion 1 </ b> A into which an optical connector 6 is inserted and fitted, and a plug that is inserted into and fitted into a receiving side optical connector 7. 1B, and can be provided so as to be interrupted between the optical connector 6 and the receiving optical connector 7.
First, the optical connector 6 and the receiving side optical connector 7 will be described.
As shown in FIG. 1, the optical connector 6 includes a ferrule 61, a sleeve-like housing main body 62 (hereinafter referred to as “housing main body”) that houses the ferrule 61, and a pair of latches 63 protruding from both sides of the housing main body 62. And a housing 64 with a latch, which is assembled at the tip of the optical fiber 101.
The optical fiber 101 is, for example, a drop cable (optical fiber cable). The drop cable has a structure in which an optical fiber is embedded in a resin coating together with a tensile body.
The optical fiber 65 accommodated in the ferrule 61 constitutes a part of the optical line on the optical fiber 101 side.
The pigtail of the optical fiber 101 extends from the rear end portion of the optical connector 6 opposite to the front end portion on the joining end surface 61a side of the ferrule 61 front end.

The housing main body 62 of the optical connector 6 has an outer shape similar to that of an optical connector plug housing of an SC type optical connector (SC: Single fiber Coupling optical fiber connector) established in JIS C 5973.
The latch 63 protrudes from the rear end portion of the housing body 62 and extends along both side surfaces 62 b of the housing body 62.
The housing main body 62 of the optical connector 6 illustrated here is made of plastic, and the latch 63 is formed on the housing main body 62 by integral molding. The latch 63 is an elastic piece protruding from the housing body 62.

The receiving side optical connector 7 has a structure in which a ferrule 74 is incorporated in a receiving housing part 73 having a connector receiving recess 71 into which the optical connector 6 is inserted from the outside, and is assembled at the tip of the optical fiber 102. .
In FIG. 1, reference numeral 75 denotes a retaining housing that houses a retaining member (not shown) that retains the tip of the optical fiber 102. A pigtail of the optical fiber 102 extends from the retaining housing 75.
As the optical fiber 102, similarly to the optical fiber 101 described above, an optical fiber cable (for example, a so-called indoor cable) having a structure in which an optical fiber is embedded in a resin coating together with a tensile body is employed. An optical fiber core, an optical fiber, an optical fiber cord, and the like can also be employed. The optical fiber 76 accommodated in the ferrule 74 constitutes a part of the optical line on the optical fiber 102 side.

The ferrule 74 is housed in a split sleeve 77 incorporated in the receiving housing portion 73 of the receiving side optical connector 7. The ferrule 74 is housed in the split sleeve 77 so that the joint end surface 74 a at the tip is the axial center of the split sleeve 77.
The split sleeve 77 is provided in the receiving housing portion 73 so as to close the back side of the connector receiving recess 71 as viewed from the opening 72 for inserting the optical connector 6 into the connector receiving recess 71. Projecting into the connector receiving recess 71 from the back wall 78.
Latches 63 on both sides of the optical connector 6 inserted and received in the connector receiving recess 71 are detachably engaged with the side wall portions 73a on both sides of the receiving housing portion 73 via the split sleeve 77. A locking recess 73b is formed. In the receiving side optical connector 7 of the illustrated example, the locking recess 73b is formed in a window shape penetrating the side wall portion 73a.

As shown in FIG. 10, the optical connector 6 is inserted into the connector receiving recess 71 of the receiving side optical connector 7 so as to be fitted to the receiving side optical connector 7 and connected to the receiving side optical connector 7. it can.
When the optical connector 6 is pushed into the connector receiving recess 71 of the receiving optical connector 7, the ferrule 61 of the optical connector 6 is inserted into the split sleeve 77 of the receiving optical connector 7, and the receiving sleeve 77 receives the optical connector 6. It is abutted against the ferrule 74 of the side optical connector 7. Thereby, the optical fibers 65 and 76 inserted and fixed to the ferrules 61 and 74 are abutted and connected to each other, and the optical fiber 101 on the optical connector 6 side and the optical fiber 102 of the receiving side optical connector 7 are optically connected.

The optical connector 6 pushed into the receiving side optical connector 7 is held by the optical connector 6 with respect to the receiving side optical connector 7 by engaging the latch 63 with both side walls 73a of the receiving side optical connector 7. The butted state of the ferrules 61 and 74 of the connector 6 and the receiving side optical connector 7 is maintained.
First, the latches 63 on both sides of the optical connector 6 are pushed into the connector receiving recesses 71 of the receiving optical connector 7 so that the separation distance between the side wall portions 73a and 73a of the receiving optical connector 7 is first reached. The difference (L1 <L2) between L1 (see FIG. 1) and the distance L2 between the latches 63 (the distance between the protruding tips of latches 66 to be described later from the latch 63) of each latch 63. ), The latches 63 are elastically deformed so that they are slightly closer to each other. As the optical connector 6 continues to be pushed into the receiving side optical connector 7, the latching claw 66 protruding from the tip of the latch 63 toward the side opposite to the housing body 62 is caused by the elasticity of the latch 63. The latch 63 is inserted into the locking recess 73b of the side wall portion 73a of the receiving side optical connector 7 (the locking claw 66 engages with the receiving side optical connector 7). Engagement is achieved.

When the optical connector 6 is pushed into the receiving optical connector 7, a pair of elastic claws 79 a protruding from a claw component 79 incorporated in the connector receiving recess 71 of the receiving optical connector 7 is used as an optical connector. The housing body 62 of the optical connector 6 is held so as to be sandwiched between the pair of elastic claws 79a. The
As the part 79 with a nail | claw, the thing similar to the part 9 with a nail | claw for optical connector adapters 1 shown to Fig.11 (a), (b), (c) is employable, for example.
In addition,

11A, 11B, and 11C, the claw-equipped component 9 is an integrally molded product made of plastic, and a ferrule insertion hole 91a that is a through-hole through which the ferrule 61 of the optical connector 6 is inserted is the center. A plate-shaped (or frame-shaped) base portion 91 formed on the base portion, and a pair of elastic claws 92 projecting from one side of the base portion 91 from both sides of the base portion 91. To do.
The elastic claw 92 corresponds to the elastic claw 79a of the part 79 with the claw illustrated in FIGS.
The clawed component 9 can be incorporated into the receiving optical connector 7 by being pushed into the connector receiving recess 71 from the opening 72 of the connector receiving recess 71 of the receiving optical connector 7. The clawed component 9 has a connector housing in such a direction that the elastic claw 92 protrudes from the base portion 91 housed in the innermost part of the connector housing recess 71 toward the opening 72 of the connector housing recess 71. It is incorporated in the recess 71. In addition, when the claw-equipped component 9 is pushed into the connector receiving recess 71 from the opening 72, the engaging claw 93, which is a small protrusion protruding from both sides of the base portion 91, has received light on the receiving side. The receiving side optical connector prevents the clawed component 9 from coming out of the opening 72 of the connector receiving recess 71 by entering the engaging recess 73b of the side wall 73a of the connector 7 and engaging with the side wall 73a. 7 (specifically, the receiving housing portion 73).

As shown in FIGS. 11B and 11C, two engaging claws 93 of the claw-equipped component 9 are provided on the both sides of the base portion 91, respectively. A latch housing groove 94 is secured between the pair of engaging claws 93 protruding from the same side of the base portion 91 so that the latch 63 of the optical connector 6 can be inserted.
The latch 63 (specifically, the locking claw 66) of the optical connector 6 that enters the locking recess 73b of the side wall 73a of the receiving side optical connector 7 and engages with the side wall 73a is engaged with the locking recess 73b. It enters into the latch housing groove 94 between the paired engagement claws 93 and is engaged with the side wall 73 a of the receiving side optical connector 7.

The pair of elastic claws 92 of the claw-equipped component 9 can cope with the detachable engagement of the optical connector 6 with the SC type optical connector (optical connector plug).
The receiving-side optical connector 7 incorporating the clawed component 9 can be connected to an SC-type optical connector and can also function as an optical connector receptacle into which the SC-type optical connector is fitted.
The receiving side optical connector 7 can also be connected to an optical connector plug (an optical connector plug without latch) other than the SC type optical connector by selecting and using the claw component 79.

Engagement of the pair of latches 63 of the optical connector 6 with both side wall portions 73a, 73a of the receiving side optical connector 7, and engagement of the housing main body 62 by the pair of elastic claws 79a of the clawed parts 79 of the receiving side optical connector 7. The holding of the optical connector 6 is achieved with respect to the receiving side optical connector 7 by realizing the holding.
When the optical connector 6 is fitted to the receiving side optical connector 7, the butting force between the ferrules 61 and 74 by a spring (not shown) housed in one or both of the optical connector 6 and the receiving side optical connector 7. Is secured.

In a state where the optical connector 6 and the receiving side optical connector 7 are connected, the both latches 63 engaged with the both side walls 73a of the receiving side optical connector 7 are operated so as to approach each other (hereinafter referred to as this). The operation is also referred to as a disengagement operation), and the engagement of the latch 63 with the side wall portion 73a of the receiving side optical connector 7 can be released (the locking pawl 66 is extracted from the locking recess 73b). The optical connector 6 can be removed from the cable.
In a state where the optical connector 6 and the receiving side optical connector 7 are connected, the latch 63 has a receiving side optical connector whose leading end side (the locking claw 66 side) from the center of the portion extending along the housing body 62. 7, the portion from the central portion to the protruding base end portion from the housing main body 62 is not stored in the receiving side optical connector 7, but is exposed outside the receiving side optical connector 7. By using this exposed portion and elastically deforming the pair of latches 63 so as to approach each other, the engagement of the latches 63 with the side wall portion 73a of the receiving side optical connector 7 can be released.
Note that the latch 63 is provided so as to extend from the projecting distal end of the projecting base end portion 63 a projecting so as to protrude outward from the housing body 62 and to be along the side surface 62 b of the housing body 62. The clearance 67 (see FIG. 1 and the like) secured between the portion and the side surface 62b of the housing main body 62 of the optical connector 6 can be elastically deformed in the direction of approaching the housing main body 62. The engagement of the receiving side optical connector 7 with respect to the side wall portion 73a can be released.

Next, the optical connector adapter 1 will be described.
1 and 2 schematically show the structure of the optical connector adapter 1.
As shown in FIGS. 1 and 2, the optical connector adapter 1 has a female housing portion 4 having a connector receiving recess 41 into which the optical connector 6 is inserted, and the optical connector 6 of the receiving side optical connector 7 inserted therein. A ferrule 8 is incorporated in the housing body 2 having a male housing portion 5 that can be inserted into the connector housing recess 71.
Further, the optical connector adapter 1 includes a clawed component 9 incorporated in the inner side of the female housing portion 4 (connector receiving recess 41).
The female housing part 4 has the same structure as that of the receiving side optical connector 7, and the optical connector 6 can be inserted and fitted (connected).
The male housing part 5 has a structure in which a plug frame body 3 having a shape similar to the housing body 62 of the optical connector 6 is provided between a pair of latches 51 (described later). The male housing portion 4 has a structure similar to the optical connector 6 as a whole, and can be inserted and fitted (connected) so as to be pushed into the receiving side optical connector 7 in the same manner as the optical connector 6. .

3 to 9 show an example of a specific structure of the optical connector adapter 1.
The housing main body 2 of the optical connector adapter 1 illustrated in FIGS. 3 to 9 includes a central wall portion 22 in which a ferrule 8 and a sleeve-like ferrule holding portion 21 into which a split sleeve 81 for housing the ferrule 8 is incorporated are formed. Have.
In the housing body 2, one side from the central wall portion 22 is the female housing portion 4, and the other side is the male housing portion 5. The central wall portion 22 is located at a boundary position between the female housing portion 4 and the male housing portion 5.
In the optical connector adapter 1, hereinafter, the side of the female housing part 4 from the central wall part 22 may be referred to as a connector receiving part 1A, and the side of the male housing part 5 may be referred to as a plug part 1B.

Here, the housing body 2 is an integrally molded product made of plastic. However, in the present invention, the housing body 2 is not limited to a resin body.
The female housing part 4 is formed by a rectangular frame-like projecting wall projecting from one side of the central wall part 22.
The male housing part 5 of the housing body 2 in the illustrated example is formed by a pair of latches 51 projecting on the opposite side of the central wall part 22 from the female housing part 4.
Note that the male housing portion 5 includes, for example, protrusions protruding from the pair of latches 51 such as an engagement release lever denoted by reference numeral 52 in the drawing.

The ferrule holding portion 21 protruding from the central wall portion 22 protrudes from the central wall portion 22 to both sides, that is, the connector receiving portion 1A side and the plug portion 1B side.
The ferrule holding portion 21 protrudes into the connector receiving recess 41 of the female housing portion 4 in the connector receiving portion 1A, and protrudes between the pair of latches 51 in the plug portion 1B.

As shown in FIG. 5, the ferrule 8 has an end on the plug portion 1 </ b> B side inserted into a split sleeve 81 housed in the ferrule holding portion 21.
The split sleeve 81 is inserted into the ferrule holding part 21 from the plug part 1B. The split sleeve 81 includes a retaining protrusion 24 projecting from the inner end of the ferrule holding portion 21 on the connector receiving portion 1A side, and an axial direction of the ferrule 8 inserted into the ferrule holding portion 21 from the plug portion 1B. It is held between the flange part 8a (see FIGS. 12A and 12B) that is externally fixed to the central portion. Specifically, the split sleeve 81 accommodates the retaining projection 24 inside the connector receiving portion 1A side end of the ferrule holding portion 21 and the axial center portion of the ferrule 8 in the flange part 8a. The fixed sleeve portion 8b, which is a sleeve-like portion fixed to the connector, is housed between the connector receiving portion 1A side end portion.
The flange part 8a will be described in detail later.

The ferrule 8 is disposed at a position where one end thereof is shifted to the plug portion 1B side with respect to the connector receiving portion 1A side end of the split sleeve 81 (longitudinal central portion of the split sleeve 81), and the other end portion is split. The sleeve 81 protrudes from the end of the plug portion 1B side.
The other end portion of the ferrule 8 is a portion that is inserted into the split sleeve 77 of the receiving side optical connector 7 and butt-connected to the ferrule 74 when the plug portion 1B of the optical connector adapter 1 is inserted into the receiving side optical connector 7. is there.

As the ferrule 8, for example, one formed of zirconia ceramic can be used. However, the forming material is not particularly limited as long as it is a known material used for the ferrule.
An optical fiber grating 82 is inserted and fixed to the ferrule 8.
Ends in the longitudinal direction of the optical fiber grating 82 are exposed at the joint end faces 83 and 84 on both sides of the ferrule 8.
Hereinafter, the ferrule 8 is also referred to as a built-in grating ferrule.

  A pair of side wall portions 42 of the female housing part 4 facing each other via the connector receiving recess 41 is provided with latches 63 on both sides of the optical connector 6 inserted and received in the connector receiving recess 41. A locking recess 43 is formed which is engageable. In the illustrated optical connector adapter 1, the locking recess 43 is formed in a window shape penetrating the side wall portion 42.

As described above, the claw-equipped component 9 is a small block component in which a pair of elastic claws 92 that are engaged with both side portions of the housing body 2 of the optical connector 6 are projected.
The elastic claw 92 of the clawed component 9 also functions to hold the SC type optical connector plug by detachably engaging with the SC type optical connector (optical connector plug) from both sides. 4 (connector receiving portion 1A) can be made to function as an optical connector receptacle of the SC type optical connector by incorporating the component 9 with claws.
The claw-equipped component 9 is assembled to the housing main body 2 by engaging the engaging claws 93 projecting on both sides so as to fit into the engaging recesses 43 of the pair of side wall portions 42 of the female housing portion 4. As a result, dropout from the connector receiving portion 1A is restricted.
The connector receiving portion 1A can also be connected to an optical connector plug (an optical connector plug without a latch) other than the SC type optical connector by selecting and using the claw component 9.
The pair of elastic claws 92 of the claw-equipped component 9 is engaged with the side wall portion of the sleeve-like housing for housing the ferrule in the optical connector plug from both sides to hold the optical connector plug.

The structure of the connector receiving portion 1A is similar to the receiving housing portion 73 of the receiving side optical connector 7, and the female housing portion of the pair of latches 62 of the optical connector 6 can be obtained simply by pushing the optical connector 6 into the connector receiving recess 41. 4 can be engaged and disengaged, the ferrule 61 can be inserted into the split sleeve 81, and the ferrule 8 of the optical connector adapter 1 can be abutted, and the connection of the optical connector 6 to the optical connector adapter 1 can be achieved.
If the pair of latches 66 of the optical connector 6 connected to the connector receiving portion 1A is disengaged, the optical connector 6 can be removed from the connector receiving portion 1A.
A separation distance L3 (see FIG. 6A) between the pair of side wall portions 42 in which the locking recess 43 is formed is from the vicinity of the locking recess 43 to the opening side (back wall) of the connector housing recess 41. As it goes to the side opposite to the portion 78), it gradually increases. The separation distance L3 is slightly smaller near the latching recess 43 than the distance L2 between the latches 63 of the optical connector 6.

The structure of the plug portion 1B is similar to that of the optical connector 6, and by simply pushing the receiving side optical connector 7 into the receiving housing portion 73, the engagement of the pair of latches 51 with respect to the receiving housing portion 73 and the receiving side The insertion of the ferrule 8 into the split sleeve 77 of the optical connector 7 and the abutment with the ferrule 74 can be realized, and the connection to the receiving side optical connector 7 can be achieved.
The engagement of the pair of latches 51 with the receiving housing portion 73 is performed by the latching claw 53 protruding from the tip of each latch 51 toward the side opposite to the ferrule 8 located between the latches 51. This is achieved by entering into the locking recess 73b of the side wall 73a of the receiving side optical connector 7 (the locking claw 53 engages with the receiving side optical connector 7).
The separation distance L4 between the latches 51 of the plug portion 1B (the separation distance between the protruding tips of the locking claws 53 from the latch 63) is slightly smaller than the separation distance L1 between the side wall portions 73a and 73a of the receiving side optical connector 7. Big.

As shown in FIG. 5 and the like, a plug frame main body 3 separate from the housing main body 2 is provided between the pair of latches 51 of the plug portion 1B and assembled to the housing main body 2.
In the illustrated optical connector adapter 1, as shown in FIG. 6 and the like, the plug frame main body 3 includes a sleeve portion 31 and a projecting piece 32 projecting outside the sleeve portion 31. This plug frame main body 3 extrapolates the sleeve portion 31 to the ferrule holding portion 21 protruding between the pair of latches 51 from the central wall portion 22 of the housing main body 2, and the concave-convex fitting with the ferrule holding portion 21, The housing body 2 is assembled. Specifically, the locking hole 33 formed in the sleeve 31 of the plug frame body 3 is protruded from the outer peripheral surface of the portion protruding from the central wall portion 22 of the ferrule holding portion 21 toward the plug portion 1B. It fits into the locking projection 23 and is firmly assembled. However, it is not limited to this, For example, the structure etc. which are assembled | attached to the center wall part 22 by uneven | corrugated fitting may be sufficient.
Here, the outer shape of the sleeve portion 31 of the plug frame body 3 is the same as the plug frame of the SC type optical connector. The projecting piece 32 is formed in a plate shape, and is disposed at a position corresponding to the side wall portion of the knob (coupling) of the SC type optical connector with respect to the sleeve portion 31.

The end portion (the other end portion) on the plug portion 1B side of the ferrule 8 with built-in grating protrudes from the end portion on the plug portion 1B side of the split sleeve 81, and the sleeve portion 31 of the plug frame body 3 assembled to the housing body 2. And protrudes from the tip of the sleeve portion 31.
As shown in FIGS. 12A and 12B, a metal flange part 8 a is fixed to the central portion in the axial direction of the built-in grating ferrule 8. This flange part 8a accommodates the axially central part of the ferrule 8 with a built-in grating and is fixed to the ferrule 8, and one axial end (end on the plug part 1B side) of the fixed sleeve part 8b. And a flange portion 8c projecting over the entire outer periphery of the sleeve portion 8b.

  As shown in FIG. 5, the outer diameter of the flange portion 8 c of the flange component 8 a fixed to the ferrule 8 with a built-in grating is larger than the inner diameter of the opening end on the plug portion 1 </ b> B side of the ferrule holding portion 21. The flange portion 8c is accommodated in a space 36 secured between the open end of the ferrule holding portion 21 on the plug portion 1B side and a stopper wall 35 protruding from the sleeve portion 31 of the plug frame body 3. The As shown in FIGS. 12A and 12B, the flange part 8a is formed in the space 36 from the inner surface of the sleeve portion 31 of the plug frame body 3 into the key grooves 8d formed at a plurality of locations in the outer peripheral direction of the flange portion 8c. The key 37 that is projected to the center of the ferrule 8 is housed and prevented from rotating, and functions as a rotation stopper around the axis of the ferrule 8.

The ferrule 8 is restricted from moving further toward the plug portion 1B by the flange portion 8c abutting against a stopper wall 35 protruding from the sleeve portion 31 inside the plug frame body 3. The stopper wall 35 functions as a stopper for preventing the split sleeve 81 and the ferrule 8 inserted into the ferrule holding part 21 from coming out from the ferrule holding part 21 to the plug part 1B side.
As shown in FIG. 5, the split sleeve 81 is sandwiched between the retaining protrusion 24 inside the connector receiving portion 1A side tip of the ferrule holding portion 21 and the connector receiving portion 1A side tip of the fixed sleeve portion 8b. The position of the ferrule 8 (the position shown in FIG. 5) is compared with the position of the ferrule 8 when the flange portion 8c of the flange part 8a hits the stopper wall 35 inside the sleeve portion 31 of the plug frame body 3. It is slightly shifted toward the receiving portion 1A. Within the range of this deviation (symbol ΔL in FIG. 5), the ferrule 8 is allowed to finely move in the axial direction of the ferrule holding portion 21.
When the optical connector 6 and the receiving side optical connector 7 are connected via the optical connector adapter 1, the ferrule 8 is finely moved by the abutment between the ferrule 61 and the ferrule 8 of the optical connector 6 and the receiving side optical connector 7. The ferrule 74 and the ferrule 8 can be reliably matched. Moreover, the urging force of the spring for generating the butt force incorporated in one or both of the optical connector 6 and the receiving side optical connector 7 is a butt force between the ferrule 61 and the ferrule 8, and the ferrule 74 and the ferrule 8. As a butting force between the ferrules 8, it acts in a balanced manner at both ends of the ferrule 8, and contributes effectively to ensuring the stability of desired optical characteristics such as connection loss.

  When the plug portion 1B is inserted into the receiving optical connector 7 to be connected, the ferrule 8 is inserted into the split sleeve 77 of the receiving optical connector 7, and the sleeve portion 31 of the plug frame body 3 and the ferrule 8 are connected. The split sleeve 77 of the receiving side optical connector 7 enters the gap 34 therebetween, and the sleeve portion 31 of the plug frame body 3 is externally inserted into the split sleeve 77 of the receiving side optical connector 7.

In this optical connector adapter 1, the locking is provided so as to protrude from the locking recesses 43 of the side wall portions 42 on both sides of the connector housing recess 41 of the female housing portion 4 to the tips of the pair of latches 51 of the plug portion 1B. The nail 53 is integrated. The side wall portions 42 on both sides of the connector housing recess 41 of the female housing portion 4 and the pair of latches 51 of the plug portion 1B have an integral structure by the housing body 2 that is a resin integrated molded product. For this reason, in this optical connector adapter 1, it protrudes at the front-end | tip of a pair of latch 51 of the plug part 1B from the latching recess 43 of the side wall part 42 of the both sides of the connector accommodation recess 41 of the female housing part 4. FIG. There is an advantage that the dimensional accuracy up to the locking claw 53 can be reliably ensured.
That is, the latching claw 66 of the latch 63 of the optical connector 6 inserted and connected to the female housing part 4 is engaged with the side wall 42 of the connector receiving part 1A, and the latching claw of the latch 51 of the plug part 1B. The separation distance L5 between 53 and the position where the receiving side optical connector 7 is engaged can be ensured with high accuracy. Accordingly, the ferrule 61 of the optical connector 6 and the ferrule 74 of the receiving optical connector 7 can be reliably abutted against the ferrule 8 with a built-in grating, and a desired joined state can be reliably obtained between the abutted ferrules.

In this optical connector adapter 1, the optical connector 6 is inserted and connected to the female housing part 4, and the plug part 1 B is inserted and connected to the receiving side optical connector 7, so that it is incorporated in the optical connector 6. The ferrule 61 and the ferrule 74 incorporated in the receiving side optical connector 7 are butted against the ferrule 8 with a built-in grating from both sides. The optical fiber 65 inserted in the ferrule 61 of the optical connector 6 and the optical fiber 76 inserted in the ferrule 74 of the receiving side optical connector 7 are the light in the ferrule 8 with a built-in grating. An optical connection is made via a fiber grating 82.
As a result, the optical fiber grating 82 in the ferrule 8 with a built-in grating is interposed between the optical fiber 101 on the optical connector 6 side and the optical fiber 102 on the receiving side optical connector 7 side. By 82, a desired wavelength selectivity such as a cutoff wavelength can be provided.

FIGS. 13 and 14 show an example of a cladding mode light absorbing means for absorbing the cladding mode light of the optical fiber grating 82.
FIG. 13 shows a structure in which, for example, an adhesive containing a light absorber such as carbon black is used as the adhesive 86 for adhering and fixing the optical fiber grating 82 accommodated in the fine hole 85 penetrating the ferrule 8 with a built-in grating. Reference numeral 821 denotes a core of the optical fiber grating 82, and 822 denotes a clad.
In this case, since the adhesive containing the light absorber functions as a clad mode light absorbing means for absorbing the clad mode light, the blocking characteristic is improved.
Even if the ferrule butt-connected to the ferrule 8 with a built-in grating has a slight optical axis shift with respect to the ferrule 8 with a built-in grating, a desired cutoff characteristic can be reliably obtained.

FIG. 14 shows that a shield 87 having a light transmitting hole 87a corresponding to the mode field diameter or core diameter is incorporated in the microhole 85 of the built-in grating ferrule 8, and the shield 87 is sandwiched from both sides so that the micropore Two optical fiber gratings 82a (82) and 82b (82) are accommodated in 85 and fixed. The shield 87 and the optical fiber gratings 82a and 82b are fixed in the micro holes 85 by, for example, adhesive fixing with an adhesive.
The shield 87 functions to shield clad mode light.
In this structure, similarly to the structure illustrated in FIG. 13, it is possible to improve the cutoff characteristics and reliably block transmission of light having a specific cutoff wavelength.

In addition, this invention is not limited to embodiment mentioned above, A various change is possible.
(1) In the above-described embodiment, the optical connector adapter having a structure corresponding to the optical connector 6 with a latch and the receiving side optical connector 7 into which the optical connector 6 is inserted and connected is illustrated. The present invention is not limited to this, and can be applied between an optical connector (optical connector plug) and a receiving side optical connector corresponding to various types of optical connectors.
(2) From the locking recesses 43 of the side wall portions 42 on both sides of the connector housing recess 41 of the female housing portion 4 to the locking claws 53 protruding from the tips of the pair of latches 51 of the plug portion 1B. From the standpoint of ensuring dimensional accuracy, the locking recesses 43 of the side wall portions 42 on both sides of the connector receiving recess 41 of the female housing portion 4 in the housing body 2 are connected to the tips of the pair of latches 51 of the plug portion 1B. A structure in which the protruding locking claws 53 are integrated is preferable, but the housing body 2 is not necessarily formed as a whole, including the ferrule holding portion 21 and the like, as in the above-described embodiment. There is no need to adopt.
For example, the structure may be such that the ferrule holding part is separate from the housing body and is separately incorporated into the housing body.

DESCRIPTION OF SYMBOLS 1 ... Optical connector adapter, 1A ... Connector receiving part, 1B ... Plug part, 2 ... Housing main body, 22 ... Central wall part, 3 ... Plug frame main body, 4 ... Female housing part, 41 ... Connector housing recess, 42 ... Side wall part, 43 ... Locking recess, 5 ... Male housing part, 51 ... Latch, 53 ... Claw, 6 ... Optical connector (optical connector plug), 61 ... Ferrule, 62 ... Housing (housing body), 63 ... Latch, 64 ... Housing with latch, 7 ... Receiving Side optical connector, 71... Connector housing recess, 73a .. side wall, 73b .. locking recess, 74... Ferrule, 8. 82: Optical fiber grating 86 ... cladding mode light absorbing means, an adhesive, 87 ... cladding mode light absorbing means, shield, 9 ... claw part, 92 ... elastic claw, 101, 102 ... optical fiber.

Claims (3)

A female housing part (4) having a connector receiving recess (41) into which the optical connector (6) is inserted;
A housing body (2) comprising a male housing part (5) insertable into a receiving side optical connector (7) having a connector receiving recess (71) into which the optical connector is inserted;
A ferrule (8) with a built-in grating in which an optical fiber grating (82) is inserted and fixed is incorporated in the housing body,
The ferrule (61) of the optical connector inserted into the female housing part and the ferrule (74) incorporated into the receiving side optical connector into which the male housing part is inserted from both sides of the ferrule with a built-in grating. The optical fiber (101) on the optical connector side and the optical fiber (102) on the receiver side optical connector side are optically connected via the optical fiber grating in the built-in grating ferrule by being abutted. And
An optical connector adapter comprising clad mode light absorbing means (86, 87) for absorbing clad mode light of the optical fiber grating in the ferrule with a built-in grating.   The clad mode light absorbing means is a light absorbent adhesive (86) provided so as to cover an outer peripheral surface of the optical fiber grating housed in a fine hole penetrating the ferrule with a built-in grating. The optical connector adapter according to claim 1.   The grating built-in ferrule has a light transmitting hole corresponding to the mode field diameter or the core diameter as the cladding mode light absorbing means, and a shield (87) for shielding the cladding mode light. The optical connector adapter according to claim 1.

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