Nothing Special   »   [go: up one dir, main page]

GB2138161A - Attenuator in optical fibre connector - Google Patents

Attenuator in optical fibre connector Download PDF

Info

Publication number
GB2138161A
GB2138161A GB08310272A GB8310272A GB2138161A GB 2138161 A GB2138161 A GB 2138161A GB 08310272 A GB08310272 A GB 08310272A GB 8310272 A GB8310272 A GB 8310272A GB 2138161 A GB2138161 A GB 2138161A
Authority
GB
United Kingdom
Prior art keywords
ferrules
tapers
optical
coupling element
attenuator
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.)
Granted
Application number
GB08310272A
Other versions
GB8310272D0 (en
GB2138161B (en
Inventor
Andrew Baxter Harding
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB08310272A priority Critical patent/GB2138161B/en
Publication of GB8310272D0 publication Critical patent/GB8310272D0/en
Priority to SE8402072A priority patent/SE8402072L/en
Publication of GB2138161A publication Critical patent/GB2138161A/en
Application granted granted Critical
Publication of GB2138161B publication Critical patent/GB2138161B/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24Coupling light guides
    • G02B6/36Mechanical coupling means
    • G02B6/38Mechanical coupling means having fibre to fibre mating means
    • G02B6/3807Dismountable connectors, i.e. comprising plugs
    • G02B6/3833Details of mounting fibres in ferrules; Assembly methods; Manufacture
    • G02B6/3834Means for centering or aligning the light guide within the ferrule
    • G02B6/3841Means for centering or aligning the light guide within the ferrule using rods, balls for light guides
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24Coupling light guides
    • G02B6/26Optical coupling means
    • G02B6/264Optical coupling means with optical elements between opposed fibre ends which perform a function other than beam splitting

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Mechanical Coupling Of Light Guides (AREA)
  • Light Guides In General And Applications Therefor (AREA)
  • Optical Couplings Of Light Guides (AREA)

Abstract

An attenuator for an optical fibre system is based upon a design of demountable optical fibre connector in which fibres (1,2) are terminated in ferrules (3,4) with conical surfaces, and the ferrules are introduced into opposite ends of a coupling member (10) whose central aperture tapers (11) inwardly from both ends. A slot (13) in the coupling member accommodates an attenuating filter (12), and the size of the tapers is such that the mated ferrules terminate just short of the filter. <IMAGE>

Description

SPECIFICATION Attenuator for optical fibre systems This invention relates to attenuators for optical fibre systems.
It has been found that optical fibre to fibre connectors with reproducable attenuation characteristics can be made in which thefibresterminate in ferrules with conical surfaces which mate in opposite ends of a coupling element whose central aperture tapers inwardly from both ends at an angle matching the tapers on the ferrules.
In a connector requiring minimal attenuation the size of the tapers is such as to bring the opposed ends of the mated ferrule terminated fibres as close together as possible without risk of direct contact between them. One way of deliberately introducing additional attenuation is to redimension the coupling element aperture so that the fibres held by it are spaced apart by a significantly greater distance than before. However, when this approach is used for providing an attenuation of in the region of 10 dB or greater for multimode fibre it has been found to introduce excessive modal noise. This has been attributed to the fact that the length of air gap to produce this magnitude of attenuation produces a coupling between the fibres that is relatively highly mode selective, discriminating against the higher order modes.
According to the present invention there is provided an optical attenuator including two ferrule terminated optical fibres and a coupling attenuating element with a central aperture incorporating an optical filter, wherein the ferrules are provided with conical tapers that mate in opposite ends of the coupling element central aperture which tapers inwardly from both ends at an angle matching the tapers on the ferrules, and is dimensioned such that the ends of the two ferrules are held in alignment just spaced from contact with the optical attenuating filter which is housed in a slot in the coupling element extending in a plane normal to the coupling element axis.
There follows a description of an optical attenuator embodying the invention in a preferred form.
The description refers to the accompanying drawings in which Figure 1 depicts a longitudinal section of the attenuator, and Figure 2 depicts an end view of the attenuator coupling element.
A pair of optical fibres 1,2 terminate in ferrules 3 and 4 in which they are secured so that each is precisely aligned with the axis of its ferrule. Typically these ferrules are made of brass or stainless steel.
One way of achieving this alignment is to provide the inside of each of the ferrules with a conical surface 5 coaxial with a conical portion of the outer surface 6 and to trap the fibre in the interface formed by three spheres 7 urged into the cone by an annular member 8. The interior is next filled with resin which is cured, and then the ferrule end is lapped back to provide a smooth end face 9 to the fibre close to the region where it is trapped by the spheres.
The two ferrules are mated by inserting them into opposite ends of the central aperture of a coupling member 10, also typically of brass or stainless steel.
This aperture is provided with conically tapered surfaces 11 lying on a common axis, and the angle of these tapers matches that of the tapers on the outer surfaces 6 of the ferrules. The spacing of these tapers is such that when the ferrules are mated their ends lie just short of a slot 13 in which an attenuating filter element 14 is housed. In a typical attenuator the filter produces an insertion loss of at least 10 dB.
Typically the filter is 125 microns thick, the slot 130 microns wide, and the separation between the ferrule ends 140 microns.
1. An optical attenuator including two ferrule terminated optical fibres and a coupling element with a central aperture incorporating an optical filter, wherein the ferrules are provided with conical tapers that mate in opposite ends of the coupling element central aperture which tapers inwardly from both ends at an angle matching the tapers on the ferrules, and is dimensioned such that the ends of the two ferrules are held in alignment just spaced from contact with the optical filter which is housed in a slot in the coupling element extending in a plane normal to the coupling element axis.
2. An optical attenuator as claimed in claim 1 and substantially as hereinbefore described with reference to the accompanying drawings.
3. An optical attenuator as claimed in claim 1 or 2, wherein the insertion loss of the optical filter is at least 10 dB.
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Attenuator for optical fibre systems This invention relates to attenuators for optical fibre systems. It has been found that optical fibre to fibre connectors with reproducable attenuation characteristics can be made in which thefibresterminate in ferrules with conical surfaces which mate in opposite ends of a coupling element whose central aperture tapers inwardly from both ends at an angle matching the tapers on the ferrules. In a connector requiring minimal attenuation the size of the tapers is such as to bring the opposed ends of the mated ferrule terminated fibres as close together as possible without risk of direct contact between them. One way of deliberately introducing additional attenuation is to redimension the coupling element aperture so that the fibres held by it are spaced apart by a significantly greater distance than before. However, when this approach is used for providing an attenuation of in the region of 10 dB or greater for multimode fibre it has been found to introduce excessive modal noise. This has been attributed to the fact that the length of air gap to produce this magnitude of attenuation produces a coupling between the fibres that is relatively highly mode selective, discriminating against the higher order modes. According to the present invention there is provided an optical attenuator including two ferrule terminated optical fibres and a coupling attenuating element with a central aperture incorporating an optical filter, wherein the ferrules are provided with conical tapers that mate in opposite ends of the coupling element central aperture which tapers inwardly from both ends at an angle matching the tapers on the ferrules, and is dimensioned such that the ends of the two ferrules are held in alignment just spaced from contact with the optical attenuating filter which is housed in a slot in the coupling element extending in a plane normal to the coupling element axis. There follows a description of an optical attenuator embodying the invention in a preferred form. The description refers to the accompanying drawings in which Figure 1 depicts a longitudinal section of the attenuator, and Figure 2 depicts an end view of the attenuator coupling element. A pair of optical fibres 1,2 terminate in ferrules 3 and 4 in which they are secured so that each is precisely aligned with the axis of its ferrule. Typically these ferrules are made of brass or stainless steel. One way of achieving this alignment is to provide the inside of each of the ferrules with a conical surface 5 coaxial with a conical portion of the outer surface 6 and to trap the fibre in the interface formed by three spheres 7 urged into the cone by an annular member 8. The interior is next filled with resin which is cured, and then the ferrule end is lapped back to provide a smooth end face 9 to the fibre close to the region where it is trapped by the spheres. The two ferrules are mated by inserting them into opposite ends of the central aperture of a coupling member 10, also typically of brass or stainless steel. This aperture is provided with conically tapered surfaces 11 lying on a common axis, and the angle of these tapers matches that of the tapers on the outer surfaces 6 of the ferrules. The spacing of these tapers is such that when the ferrules are mated their ends lie just short of a slot 13 in which an attenuating filter element 14 is housed. In a typical attenuator the filter produces an insertion loss of at least 10 dB. Typically the filter is 125 microns thick, the slot 130 microns wide, and the separation between the ferrule ends 140 microns. CLAIMS
1. An optical attenuator including two ferrule terminated optical fibres and a coupling element with a central aperture incorporating an optical filter, wherein the ferrules are provided with conical tapers that mate in opposite ends of the coupling element central aperture which tapers inwardly from both ends at an angle matching the tapers on the ferrules, and is dimensioned such that the ends of the two ferrules are held in alignment just spaced from contact with the optical filter which is housed in a slot in the coupling element extending in a plane normal to the coupling element axis.
2. An optical attenuator as claimed in claim 1 and substantially as hereinbefore described with reference to the accompanying drawings.
3. An optical attenuator as claimed in claim 1 or 2, wherein the insertion loss of the optical filter is at least 10 dB.
GB08310272A 1983-04-15 1983-04-15 Attenuator in optical fibre connector Expired GB2138161B (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB08310272A GB2138161B (en) 1983-04-15 1983-04-15 Attenuator in optical fibre connector
SE8402072A SE8402072L (en) 1983-04-15 1984-04-13 OPTICAL FIBER SYSTEM DUMPING

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB08310272A GB2138161B (en) 1983-04-15 1983-04-15 Attenuator in optical fibre connector

Publications (3)

Publication Number Publication Date
GB8310272D0 GB8310272D0 (en) 1983-05-18
GB2138161A true GB2138161A (en) 1984-10-17
GB2138161B GB2138161B (en) 1986-05-08

Family

ID=10541168

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08310272A Expired GB2138161B (en) 1983-04-15 1983-04-15 Attenuator in optical fibre connector

Country Status (2)

Country Link
GB (1) GB2138161B (en)
SE (1) SE8402072L (en)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2173319A (en) * 1985-04-02 1986-10-08 Kinaut Instr Ltd Attenuators for optical fibres
US4900124A (en) * 1988-12-12 1990-02-13 American Telephone & Telegraph Company, At&T Bell Laboratories Biconic optical fiber connecting device having attenuator
US4989938A (en) * 1988-09-08 1991-02-05 Light Control Systems, Inc. Continuously variable fiber optic attenuator
FR2657697A1 (en) * 1990-01-29 1991-08-02 Radiall Sa CONNECTOR FOR OPTICAL FIBERS.
US5062684A (en) * 1990-01-17 1991-11-05 At&T Bell Laboratories Optical fiber filter
EP0457268A2 (en) * 1990-05-16 1991-11-21 Hirose Electric Co., Ltd. Multiple optical fiber connector terminal and method of making same
EP0457284A2 (en) * 1990-05-16 1991-11-21 Hirose Electric Co., Ltd. Optical fiber connector terminal and method of making same
EP0457266A2 (en) * 1990-05-16 1991-11-21 Hirose Electric Co., Ltd. Optical fiber connector terminal and method of making same
US5073004A (en) * 1990-05-18 1991-12-17 At&T Bell Laboratories Tunable optical filter
EP0475572A1 (en) * 1990-08-13 1992-03-18 AT&T Corp. Optical fiber connecting device including attenuator
US5208886A (en) * 1990-01-17 1993-05-04 At&T Bell Laboratories Methods of making an optical fiber filter
US5319733A (en) * 1992-01-02 1994-06-07 Adc Telecommunications, Inc. Variable fiber optical attenuator
US5588087A (en) * 1992-01-02 1996-12-24 Adc Telecommunications, Inc. Overlapping fusion attenuator
EP0852338A1 (en) * 1997-01-02 1998-07-08 Lucent Technologies Inc. Optical packaging assembly for transmissive devices
US6433924B1 (en) * 2000-11-14 2002-08-13 Optical Coating Laboratory, Inc. Wavelength-selective optical amplifier
CN101916899A (en) * 2010-06-30 2010-12-15 南京信息工程大学 Telescopiform resistance high-voltage pulse attenuator

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2173319A (en) * 1985-04-02 1986-10-08 Kinaut Instr Ltd Attenuators for optical fibres
US4989938A (en) * 1988-09-08 1991-02-05 Light Control Systems, Inc. Continuously variable fiber optic attenuator
EP0373825A3 (en) * 1988-12-12 1991-03-27 AT&T Corp. Biconic optical fiber connecting device having attenuator
US4900124A (en) * 1988-12-12 1990-02-13 American Telephone & Telegraph Company, At&T Bell Laboratories Biconic optical fiber connecting device having attenuator
EP0373825A2 (en) * 1988-12-12 1990-06-20 AT&T Corp. Biconic optical fiber connecting device having attenuator
US5062684A (en) * 1990-01-17 1991-11-05 At&T Bell Laboratories Optical fiber filter
US5208886A (en) * 1990-01-17 1993-05-04 At&T Bell Laboratories Methods of making an optical fiber filter
EP0441676A1 (en) * 1990-01-29 1991-08-14 RADIALL Société anonyme dite: Connector for optical fibres
FR2657697A1 (en) * 1990-01-29 1991-08-02 Radiall Sa CONNECTOR FOR OPTICAL FIBERS.
US5134676A (en) * 1990-01-29 1992-07-28 Radiall Connector for fiber optics
EP0457268A2 (en) * 1990-05-16 1991-11-21 Hirose Electric Co., Ltd. Multiple optical fiber connector terminal and method of making same
EP0457284A2 (en) * 1990-05-16 1991-11-21 Hirose Electric Co., Ltd. Optical fiber connector terminal and method of making same
EP0457266A2 (en) * 1990-05-16 1991-11-21 Hirose Electric Co., Ltd. Optical fiber connector terminal and method of making same
EP0457266A3 (en) * 1990-05-16 1992-05-06 Hirose Electric Co., Ltd. Optical fiber connector terminal and method of making same
EP0457268A3 (en) * 1990-05-16 1992-05-13 Hirose Electric Co., Ltd. Multiple optical fiber connector terminal and method of making same
EP0457284A3 (en) * 1990-05-16 1992-05-13 Hirose Electric Co., Ltd. Optical fiber connector terminal and method of making same
US5073004A (en) * 1990-05-18 1991-12-17 At&T Bell Laboratories Tunable optical filter
EP0475572A1 (en) * 1990-08-13 1992-03-18 AT&T Corp. Optical fiber connecting device including attenuator
US5319733A (en) * 1992-01-02 1994-06-07 Adc Telecommunications, Inc. Variable fiber optical attenuator
US5588087A (en) * 1992-01-02 1996-12-24 Adc Telecommunications, Inc. Overlapping fusion attenuator
EP0852338A1 (en) * 1997-01-02 1998-07-08 Lucent Technologies Inc. Optical packaging assembly for transmissive devices
US5940558A (en) * 1997-01-02 1999-08-17 Lucent Technologies, Inc. Optical packaging assembly for transmissive devices
US6433924B1 (en) * 2000-11-14 2002-08-13 Optical Coating Laboratory, Inc. Wavelength-selective optical amplifier
CN101916899A (en) * 2010-06-30 2010-12-15 南京信息工程大学 Telescopiform resistance high-voltage pulse attenuator
CN101916899B (en) * 2010-06-30 2013-01-02 南京信息工程大学 Telescopiform resistance high-voltage pulse attenuator

Also Published As

Publication number Publication date
GB8310272D0 (en) 1983-05-18
SE8402072D0 (en) 1984-04-13
SE8402072L (en) 1984-10-16
GB2138161B (en) 1986-05-08

Similar Documents

Publication Publication Date Title
GB2138161A (en) Attenuator in optical fibre connector
US4183619A (en) Connector pin assembly and method for terminating an optical fiber
US4842363A (en) Fiber optic connector, tool for assembling fiber optic connector and method of assembling fiber optic connectors
EP0429163B1 (en) Optical fiber splicing device
KR960013800B1 (en) Multifiber optical connector plug with low reflection and low insertion loss
US4303304A (en) Universal optical waveguide alignment ferrule
US5923805A (en) Connector for plastic optical fiber
US4208092A (en) Fiber optic multi-cable pair connector
US4378145A (en) Method and apparatus for joining optical elements
US5050956A (en) Optical fiber attenuator and connecting element
JPS583392B2 (en) Lightwave energy transmission device
US4836637A (en) Expanded-beam fiber-optic connector
EP0705448A1 (en) Ferrule, fiber optic connector using such ferrule and method of preparing the ferrule
JPS5848082B2 (en) fiber optic connector assembly
US4192575A (en) Guide-connector assembly for joining optical fibers and method of making guide therefor
US6415076B1 (en) Mode conditioning patch for facilitating signal transmission from single mode optical fiber to multimode optical fiber
US6048102A (en) Optical connector which provides a disconnection state between two optical fibers where light is totally reflected at an end face of one fiber
US5142600A (en) Optical fiber quick connect/disconnect for a power laser
US5062683A (en) Strain relief connector for optical fiber
US5109468A (en) Fixed value fiber optic attenuator
CA2137239A1 (en) Fiber optic connector
US5263106A (en) Fiber optic attenuator for use with ferrules
EP0575009A1 (en) Method for fusion-forming an optical signal attenuator
EP0262765B1 (en) Fiber optic connector, tool for assembling fiber optic connector and method of assembling fiber optic connectors
US5018823A (en) Single channel high power fiber optic connector

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee