CA1068953A - Optical fibre connector for variable signal attenuation - Google Patents
Optical fibre connector for variable signal attenuationInfo
- Publication number
- CA1068953A CA1068953A CA275,742A CA275742A CA1068953A CA 1068953 A CA1068953 A CA 1068953A CA 275742 A CA275742 A CA 275742A CA 1068953 A CA1068953 A CA 1068953A
- Authority
- CA
- Canada
- Prior art keywords
- fibre
- optical
- bore
- members
- accept
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/264—Optical coupling means with optical elements between opposed fibre ends which perform a function other than beam splitting
- G02B6/266—Optical coupling means with optical elements between opposed fibre ends which perform a function other than beam splitting the optical element being an attenuator
Abstract
OPTICAL FIBRE CONNECTOR FOR
VARIABLE SIGNAL ATTENUATION
Abstract of the Disclosure An optical fibre connector is disclosed for variable optical signal attenuation. The attenuator comprises a connecting element with a common bore of size to accept with close sliding fit two optical fibres in end to end relationship, and a positioning means for varying the end separation of said optical fibres relative to one another.
- i -
VARIABLE SIGNAL ATTENUATION
Abstract of the Disclosure An optical fibre connector is disclosed for variable optical signal attenuation. The attenuator comprises a connecting element with a common bore of size to accept with close sliding fit two optical fibres in end to end relationship, and a positioning means for varying the end separation of said optical fibres relative to one another.
- i -
Description
68~53 This invention relates to connecting two optical fibres in end to end relationship and more particularly to connecting two optical fibres in end to end relationship with a predetermined amount of variable end separation for providing variable optical signal attenuation.
In the testing of fibre optic communication systems it is often necessary to insert a known amount of attenuation in the optical transmission path. Fixed attenuation has been realized by installing a splice element such as described in U.S. patent no. 3,972,585, such that the axial end separation between the fibres is a predetermined value to give the required attenuation. Such an approach means that a new attenuator has to be made for each value of attenuation wanted.
An optical fibre is extremely fragile and positioning and holding must be done without damage to the fibres. An optical fibre usually comprises a light propagating core of one predetermined refractive index and having an outer cladding layer of a lower refractive indexO The materials are usually glass. An alternative form has a separate outer layer, or cladding, but the fibre has a variable refractive index across its core, the index being higher at the fibre centre and lower at the outer circumference.
The fibre is covered with a flexible material as an example plastic, for protection and ease of handling.
The present invention provides the accurate end to end connection of optical fibres with a variable end separation by positioning the fibres in a tubular connecting ~- member such as described in U.S. Patent No. 3,972,585. Generally, one fibre is permanently held in the connecting member, as by ~ crimping or bonding, and the other fibre is moved by a linear ; ' ..... -...... .. ... " ,. . , , ~
. , ;' . . . ,' . ': . ' . - , . . . ' "' i ,`
positioner which moves the fibre back and forth axially to increase and decrease the end separation of the two fibres, thus increasing and decreasing the attenuation.
Before being positioned in the connecting me~lber, khe ends of the fibres are stripped of the coatings ;~
and the end surfaces prepared to be smooth, flat and perpendicular to the axis of the fibre. -~
The invention will be readily understood by the following description of certain embodiments, by way of example, in conjunction with the accompanying drawings, in which:-Figure 1 illustrates the principal of theinvention;
Figure 2 is a cross-section of an embodiment of the invention showing zero separation;
Figure 3 is a cross-section along the line A-A of Figure 2;
Figure 4 is a cross-section along the line B-B of Figure 2; ;
Figure 5 is a cross-section of an embodiment of the invention illustrating external connections;
Figure 6 is a cross-section along the line C-C of Figure 5; ~, Figure 7 is a graph of attenuation vs separation. -Figure 1 illustrates the principal of the ` invention where the tubular connecting member ~ has at each end a bore 9 of close sliding fit over coated fibres 10 and 14 and a central bore 11 which is a close sliding fit on the opposed uncoated fibre ends 12. For ease of insertion of the uncoated fibre ends 12 an inclined surface 13 e~tends between
In the testing of fibre optic communication systems it is often necessary to insert a known amount of attenuation in the optical transmission path. Fixed attenuation has been realized by installing a splice element such as described in U.S. patent no. 3,972,585, such that the axial end separation between the fibres is a predetermined value to give the required attenuation. Such an approach means that a new attenuator has to be made for each value of attenuation wanted.
An optical fibre is extremely fragile and positioning and holding must be done without damage to the fibres. An optical fibre usually comprises a light propagating core of one predetermined refractive index and having an outer cladding layer of a lower refractive indexO The materials are usually glass. An alternative form has a separate outer layer, or cladding, but the fibre has a variable refractive index across its core, the index being higher at the fibre centre and lower at the outer circumference.
The fibre is covered with a flexible material as an example plastic, for protection and ease of handling.
The present invention provides the accurate end to end connection of optical fibres with a variable end separation by positioning the fibres in a tubular connecting ~- member such as described in U.S. Patent No. 3,972,585. Generally, one fibre is permanently held in the connecting member, as by ~ crimping or bonding, and the other fibre is moved by a linear ; ' ..... -...... .. ... " ,. . , , ~
. , ;' . . . ,' . ': . ' . - , . . . ' "' i ,`
positioner which moves the fibre back and forth axially to increase and decrease the end separation of the two fibres, thus increasing and decreasing the attenuation.
Before being positioned in the connecting me~lber, khe ends of the fibres are stripped of the coatings ;~
and the end surfaces prepared to be smooth, flat and perpendicular to the axis of the fibre. -~
The invention will be readily understood by the following description of certain embodiments, by way of example, in conjunction with the accompanying drawings, in which:-Figure 1 illustrates the principal of theinvention;
Figure 2 is a cross-section of an embodiment of the invention showing zero separation;
Figure 3 is a cross-section along the line A-A of Figure 2;
Figure 4 is a cross-section along the line B-B of Figure 2; ;
Figure 5 is a cross-section of an embodiment of the invention illustrating external connections;
Figure 6 is a cross-section along the line C-C of Figure 5; ~, Figure 7 is a graph of attenuation vs separation. -Figure 1 illustrates the principal of the ` invention where the tubular connecting member ~ has at each end a bore 9 of close sliding fit over coated fibres 10 and 14 and a central bore 11 which is a close sliding fit on the opposed uncoated fibre ends 12. For ease of insertion of the uncoated fibre ends 12 an inclined surface 13 e~tends between
- 2 -. ,.
1~6~3~53 .
the central bore 11 and the end bores 9. As an example the central bore 11 may be produced by a section which is preformed :-by deforming the walls of the member inwards to define the smaller central bore 11. Fibre 14 is stripped of its coating and placed into the tubular connecting member 8 and held in place by a crimp or bond 15, the fibre 14 may be supported by support member 16. Fibre 10 is stripped of its coating and supported on an axial positioner 17 by support member 18. The ~;
axial separation 19 of the fibre 14 and 10 is increased or 10 decreased by moving the axial positioner 17 back and forth .
along the axis o~ fibre 10.
Figure 2 illustrates a housing 20 have a bore 21 for supporting section 25 of positioning member 24 and ~.
a bore 23 for supporting section 27 of positioning member 24.
Housing member 20 has a hollowed portion 22 large enough to accept captive nut 31. The positioning member 24 is a basically cylindrical shape comprised of three sections. Section 25 is :
mounted in bore 21, section 26 has a reduced diameter and is threaded to accept captive nut 31, and section 27 has a further reduced diameter and is mounted in bore 23.
Positioning member 24 has an axial bore 28 therethrough of diameter sufficient to accept connecting element 8. A bore 29 of the same diameter as that of bore 28 . is provided in the end wall 30 of housing 20 in order to allow fibre 14 to pass through.
Captive nut 31 may have a knurled sur~ace to . allow for easier rotation.
,' Figure 3 is a cross~section along the line , . .
A-A of an embodiment as illustrated in Figure 2. Housing member 20 has a generally circular cross-section with a cutoff section 32 to expose captive nut 31. Bore 23 supports ~ ,:
': ;' ``` ~06~5~S3 ..: -section 25 of the positioning member 24 of Figure 2. Connecting element 8 with fibre 10 is shown in position in the centre of section 25.
Figure 4 is a cross-section along the line B-B of Figure 2 and illustrates the cross-sectional form of the hollowed section 22, and the captive nut 31. Fibre 14 is shown in the bore 28.
Figure 5 illustrates an embodiment of the invention in which a containing member 50 surrounds a connector as illustrated in Figure 2 for protection and ease of handling.
Bulkhead optical connectors 51 are provided through the `
containing member 50 to allow for interconnection to the connector. The movement of the fibres during variation of the end separation is taken up at the bends in fibres 52. Mounting screws 53 are shown on top of housing member 20. Side 54 of the containing member 50 may be transparent in order that calibrations mark 55 may be seen from outside. A hand hole 56 is provided in side 54 for adjustment of the end separation of fibres 10 and 14 by rotating captive nut 31. A transparent or 20 otherwise cover plate 57 may cover the hand hole when not in -use.
Figure 6 illustrates a cross-section of Figure 5 at the line C-C. The containing member 50 supports housing member 20 at the mounting screws 53.
Figure 7 shows a graph of the optical attenuation vs the incremental end separation of the fibres, experimental and theoretical. The splice element was prefilled with index matching fluid for this experiment but in practice may not be.
A method of measuring the attenuation is illustrated by the dotted boxes of Figure 5. An optical : ~:
~1~685~53 signal source 70 is connected to one of the bulkhead optical connectors 51. The output optical signal Erom the attenuator is fed to an optical siynal detector 71. The output from the signal detector 71 is processed by the signal measurement circuit 72. The separation of the fibre is varied from zero separation until the desired attenuation is achieved.
:- .. : .. :... . -
1~6~3~53 .
the central bore 11 and the end bores 9. As an example the central bore 11 may be produced by a section which is preformed :-by deforming the walls of the member inwards to define the smaller central bore 11. Fibre 14 is stripped of its coating and placed into the tubular connecting member 8 and held in place by a crimp or bond 15, the fibre 14 may be supported by support member 16. Fibre 10 is stripped of its coating and supported on an axial positioner 17 by support member 18. The ~;
axial separation 19 of the fibre 14 and 10 is increased or 10 decreased by moving the axial positioner 17 back and forth .
along the axis o~ fibre 10.
Figure 2 illustrates a housing 20 have a bore 21 for supporting section 25 of positioning member 24 and ~.
a bore 23 for supporting section 27 of positioning member 24.
Housing member 20 has a hollowed portion 22 large enough to accept captive nut 31. The positioning member 24 is a basically cylindrical shape comprised of three sections. Section 25 is :
mounted in bore 21, section 26 has a reduced diameter and is threaded to accept captive nut 31, and section 27 has a further reduced diameter and is mounted in bore 23.
Positioning member 24 has an axial bore 28 therethrough of diameter sufficient to accept connecting element 8. A bore 29 of the same diameter as that of bore 28 . is provided in the end wall 30 of housing 20 in order to allow fibre 14 to pass through.
Captive nut 31 may have a knurled sur~ace to . allow for easier rotation.
,' Figure 3 is a cross~section along the line , . .
A-A of an embodiment as illustrated in Figure 2. Housing member 20 has a generally circular cross-section with a cutoff section 32 to expose captive nut 31. Bore 23 supports ~ ,:
': ;' ``` ~06~5~S3 ..: -section 25 of the positioning member 24 of Figure 2. Connecting element 8 with fibre 10 is shown in position in the centre of section 25.
Figure 4 is a cross-section along the line B-B of Figure 2 and illustrates the cross-sectional form of the hollowed section 22, and the captive nut 31. Fibre 14 is shown in the bore 28.
Figure 5 illustrates an embodiment of the invention in which a containing member 50 surrounds a connector as illustrated in Figure 2 for protection and ease of handling.
Bulkhead optical connectors 51 are provided through the `
containing member 50 to allow for interconnection to the connector. The movement of the fibres during variation of the end separation is taken up at the bends in fibres 52. Mounting screws 53 are shown on top of housing member 20. Side 54 of the containing member 50 may be transparent in order that calibrations mark 55 may be seen from outside. A hand hole 56 is provided in side 54 for adjustment of the end separation of fibres 10 and 14 by rotating captive nut 31. A transparent or 20 otherwise cover plate 57 may cover the hand hole when not in -use.
Figure 6 illustrates a cross-section of Figure 5 at the line C-C. The containing member 50 supports housing member 20 at the mounting screws 53.
Figure 7 shows a graph of the optical attenuation vs the incremental end separation of the fibres, experimental and theoretical. The splice element was prefilled with index matching fluid for this experiment but in practice may not be.
A method of measuring the attenuation is illustrated by the dotted boxes of Figure 5. An optical : ~:
~1~685~53 signal source 70 is connected to one of the bulkhead optical connectors 51. The output optical signal Erom the attenuator is fed to an optical siynal detector 71. The output from the signal detector 71 is processed by the signal measurement circuit 72. The separation of the fibre is varied from zero separation until the desired attenuation is achieved.
:- .. : .. :... . -
Claims (3)
EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:-
1. An optical fiber connector for variable optical signal attenuation, comprising;
a connecting element with a common bore of a size to accept with close sliding fit two uncoated optical fibers in end-to-end relationship, said connecting element including two members, one moveable axially relative to the other, a fiber secured in each member; and positioning means acting between said members to move one member axially relative to the other to vary the gap between the ends of the fibers.
a connecting element with a common bore of a size to accept with close sliding fit two uncoated optical fibers in end-to-end relationship, said connecting element including two members, one moveable axially relative to the other, a fiber secured in each member; and positioning means acting between said members to move one member axially relative to the other to vary the gap between the ends of the fibers.
2. A connector as claimed in claim 1, including two further bores, one on each end of said common bore, a first of size to accept a first coated fibre with close sliding fit and means for permanently securing said coated fibre to said element, and a second bore of size to accept a second coated optical fibre with sliding fit to allow axial movement of the fibre.
3. A connector as claimed in claim 1, wherein the positioning means comprises a captive nut in a housing, said housing forming one of said members and said nut mounted on a threaded portion on the other of said members.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA275,742A CA1068953A (en) | 1977-04-06 | 1977-04-06 | Optical fibre connector for variable signal attenuation |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA275,742A CA1068953A (en) | 1977-04-06 | 1977-04-06 | Optical fibre connector for variable signal attenuation |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1068953A true CA1068953A (en) | 1980-01-01 |
Family
ID=4108345
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA275,742A Expired CA1068953A (en) | 1977-04-06 | 1977-04-06 | Optical fibre connector for variable signal attenuation |
Country Status (1)
Country | Link |
---|---|
CA (1) | CA1068953A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2504690A1 (en) * | 1981-04-27 | 1982-10-29 | Raychem Corp | METHODS, APPARATUS AND ARTICLES FOR OPTICAL FIBER SYSTEMS |
WO1985001118A1 (en) * | 1983-08-29 | 1985-03-14 | American Telephone & Telegraph Company | Optical fiber connector |
FR2557981A1 (en) * | 1981-04-27 | 1985-07-12 | Raychem Corp | Methods, apparatuses and articles for fibre-optic systems |
US4664732A (en) * | 1981-04-27 | 1987-05-12 | Raychem Corp. | Methods and apparatus for optical fiber systems |
FR2590370A1 (en) * | 1985-11-21 | 1987-05-22 | Cit Alcatel | Adjustable attenuator connector for optical fibres |
US4896938A (en) * | 1983-08-29 | 1990-01-30 | American Telephone And Telegraph Company, At&T Bell Laboratories | Optical fiber connector comprising glass tubes |
US4934785A (en) * | 1983-08-29 | 1990-06-19 | American Telephone And Telegraph Company | Optical fiber connector |
-
1977
- 1977-04-06 CA CA275,742A patent/CA1068953A/en not_active Expired
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2504690A1 (en) * | 1981-04-27 | 1982-10-29 | Raychem Corp | METHODS, APPARATUS AND ARTICLES FOR OPTICAL FIBER SYSTEMS |
EP0063954A1 (en) * | 1981-04-27 | 1982-11-03 | RAYCHEM CORPORATION (a Delaware corporation) | Methods, apparatus and articles for optical fiber systems |
WO1982003922A1 (en) * | 1981-04-27 | 1982-11-11 | Ltd Raychem | Methods,apparatus and articles for optical fiber systems |
FR2557981A1 (en) * | 1981-04-27 | 1985-07-12 | Raychem Corp | Methods, apparatuses and articles for fibre-optic systems |
US4664732A (en) * | 1981-04-27 | 1987-05-12 | Raychem Corp. | Methods and apparatus for optical fiber systems |
WO1985001118A1 (en) * | 1983-08-29 | 1985-03-14 | American Telephone & Telegraph Company | Optical fiber connector |
US4896938A (en) * | 1983-08-29 | 1990-01-30 | American Telephone And Telegraph Company, At&T Bell Laboratories | Optical fiber connector comprising glass tubes |
US4934785A (en) * | 1983-08-29 | 1990-06-19 | American Telephone And Telegraph Company | Optical fiber connector |
FR2590370A1 (en) * | 1985-11-21 | 1987-05-22 | Cit Alcatel | Adjustable attenuator connector for optical fibres |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4145110A (en) | Optical fibre connector for variable signal attenuation | |
US4261640A (en) | In-line optic attenuators for optical fibers | |
US4989938A (en) | Continuously variable fiber optic attenuator | |
US4148559A (en) | Method and device for connecting optical fibres | |
US5125057A (en) | Optical fiber splicing device | |
US4904044A (en) | Continuously variable fiber optic attenuator | |
CN1277137C (en) | Optical interconnect assemblies and methods therefor | |
CA1113761A (en) | Optical fiber connector apparatus | |
US6767139B2 (en) | Six-port optical package and method of manufacturing | |
US20170235063A1 (en) | Strain relief boot and fiber optic cable assembly including the same | |
KR920004430B1 (en) | Optical fiber connector | |
US5469522A (en) | Optical fiber splice interconnection and usage method | |
US4697869A (en) | Attenuator for optical fiber | |
CA2019902C (en) | Optical fibre cable | |
EP0564133A1 (en) | Single mode fiber optic variable attenuator | |
US20040234204A1 (en) | Multiple-port optical package and DWDM module | |
CA1068953A (en) | Optical fibre connector for variable signal attenuation | |
WO2011139046A2 (en) | Optical fiber connector in which bragg grating is built | |
US4930859A (en) | Fiber optic splice assembly | |
US4383732A (en) | Fiber optic connector | |
US5805760A (en) | Optical filter for telecommunications | |
US5009479A (en) | Optical fiber coupling device and method for its use | |
US5085494A (en) | Fiber optic splice means and method | |
EP0164784A1 (en) | Method of interconnecting optical fibres | |
CA1246914A (en) | Connection of optical fibres by fusion splicing |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
MKEX | Expiry |