Patent US5039193A successfully refreshed from Google Patents.
US5039193A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fibre optic single mode rotary joint
Assignee: Focal Technologies Corp
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Filing: 1990-04-03
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Granted: 1991-08-13
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Expires: 2010-04-03
Abstract
Abstract The invention is a rotary joint for singlemode optical fibers, having a fixed and a rotating part to permit the transmission of optical signals across a rotational interface (such as a winch or turret) with minimal insertion loss and, in particular, low reflections (good return loss). There is no need of conversion to electrical signals; the device is passive. It may be use an oil of refractive index matched to that of the glass fibers and to that of fiber tapers or lenses used to expand the beam emitted from one fiber and contract it for transmission into the other fiber. The device is bidirectional. By use foil, through precision techniques for building and mounting the optical and mechanical components, and by use of advanced bearings, both the insertion loss and unwanted reflections (return loss) can be minimized, thereby making it suitable for use with singlemode fiber. Insertion loss can be further reduced in conjunction with index-matching fluid by using optical elements (lenses, tapers, fibers) having angled or curved facets rather than perpendicular facets. Oil filling has the further advantage of pressure compensation allowing the device to operate at any ambient pressure. Lenses having curved surfaces can be accommodated by the use of fluid having a refractive index different from that of the lens material.
Inventors
- 👤 James W. Snow
- 👤 Graham A. J. Smith
- 👤 Geoffrey H. Channer
- 👤 John W. Purdy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:43
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/32; G02B6/262; G02B6/327; G02B6/36; G02B6/3604; H; H04; H04B; H04B10/00; H04B10/80; H04B10/801
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
108 words
A fiber optic rotary joint for use with singlemode optical fibers comprising: a stator member; means for axially mounting a first singlemode optical fiber and first light beam expanding and collimating means in said stator member; a rotor member bearingly mounted in said stator member for rotation relative thereto; means for axially mounting a second singlemode optical fiber and second light beam expanding and collimating means in said rotor member; means establishing a sealed zone between said rotor and stator members, which zone includes an optical path between said first and second light beam expanding and collimating means; and an optically transmissive fluid contained within said sealed zone.
Claim 2
Dependent Claim
108 words
A fiber optic rotary joint for use with singlemode optical fibers comprising: a stator member; means for axially mounting a first singlemode optical fiber and first light beam expanding and collimating means in said stator member; a rotor member bearingly mounted in said stator member for rotation relative thereto; means for axially mounting a second singlemode optical fiber and second light beam expanding and collimating means in said rotor member; means establishing a sealed zone between said rotor and stator members, which zone includes an optical path between said first and second light beam expanding and collimating means; and an optically transmissive fluid contained within said sealed zone.
Claim 3
Dependent Claim
47 words
The rotary joint of claim 1 wherein said sealed zone establishing means comprises rotary seal means between said rotor and stator members, a fluid fill port in said stator member communicating with said sealed zone, and a plug member releasably and sealingly received in said fill port.
Claim 4
Dependent Claim
50 words
The rotary joint of claim 2 including a pressure compensation chamber in said stator member communicating with said sealed zone, a freely movably pressure compensating piston within said chamber, and a non-sealed cap member for preventing the piston from exiting said chamber should it reach the end of its travel.
Claim 5
Dependent Claim
22 words
The rotary joint of claim 3 wherein said fluid matches the index of refraction of said light beam expanding and collimating means.
Claim 6
Dependent Claim
79 words
The rotary joint of claim 1 including a pair of bearing members supporting said rotor member within an axial bore of said stator member, an annular spacer member spacing said bearing members apart, an annular end cap surrounding said rotor member, a pair of annular sealing rings sealing said end cap to said bore and said rotor member respectively, and an annular resilient wedge member received in a peripheral groove in said bore and bearing against said end cap.
Claim 7
Dependent Claim
19 words
The rotary joint of claim 1 wherein said light beam expanding and collimating means comprise graded index rod lenses.
Claim 8
Dependent Claim
17 words
The rotary joint of claim 1 wherein said light beam expanding and collimating means comprise aspheric lenses.
Claim 9
Dependent Claim
17 words
The rotary joint of claim 1 wherein said light beam expanding and collimating means comprise spherical lenses.
Claim 10
Dependent Claim
18 words
The rotary joint of claim 1 wherein said light beam expanding and collimating means comprise optical fiber tapers.
Claim 11
Dependent Claim
27 words
The rotary joint of claim 6 wherein said rod lenses have opposing end facets that are plane, angled or curved relative to the axis of said joint.
Claim 12
Dependent Claim
28 words
The rotary joint of claim 9 wherein said optical fiber tapers have opposing end facets that are plane, angled or curved relative to the axis of said joint.
Claim 13
Dependent Claim
116 words
A fiber optic rotary joint for use with singlemode optical fibers comprising: a stator member; means for axially mounting a first singlemode optical fiber and first light beam expanding and collimating means in said stator member; a generally frustoconical first bearing surface in said stator member, opening outwardly away from said first light beam expanding and collimating means; a rotor member having a second generally frustoconical bearing surface matable with said first bearing surface; means for axially mounting a second singlemode optical fiber and second light beam expanding and collimating means in said rotor member; an end cap releasably secured to said stator member; and thrust bearing means between said end cap and said rotor member.
Claim 14
Dependent Claim
116 words
A fiber optic rotary joint for use with singlemode optical fibers comprising: a stator member; means for axially mounting a first singlemode optical fiber and first light beam expanding and collimating means in said stator member; a generally frustoconical first bearing surface in said stator member, opening outwardly away from said first light beam expanding and collimating means; a rotor member having a second generally frustoconical bearing surface matable with said first bearing surface; means for axially mounting a second singlemode optical fiber and second light beam expanding and collimating means in said rotor member; an end cap releasably secured to said stator member; and thrust bearing means between said end cap and said rotor member.
Claim 15
Dependent Claim
17 words
The rotary joint of claim 12 including lubricating means between said first and second frustoconical bearing surfaces.
Claim 16
Dependent Claim
19 words
The rotary joint of claim 12 wherein said light beam expanding and collimating means comprise graded index rod lenses.
Claim 17
Dependent Claim
17 words
The rotary joint of claim 12 wherein said light beam expanding and collimating means comprise aspheric lenses.
Claim 18
Dependent Claim
17 words
The rotary joint of claim 12 wherein said light beam expanding and collimating means comprise spherical lenses.
Claim 19
Dependent Claim
18 words
The rotary joint of claim 12 wherein said light beam expanding and collimating means comprise optical fiber tapers.
Claim 20
Dependent Claim
27 words
The rotary joint of claim 14 wherein said rod lenses have opposing end facets that are plane, angled or curved relative to the axis of said joint.
Claim 21
Dependent Claim
28 words
The rotary joint of claim 17 wherein said optical fiber tapers have opposing end facets that are plane, angled or curved relative to the axis of said joint.
Claim 22
Dependent Claim
25 words
The rotary joint of claim 12 including an index-matching fluid between said bearing surfaces and said first and second light beam expanding and collimating means.
Claim 23
Dependent Claim
116 words
A fiber optic rotary joint for use with multimode optical fibers comprising: a stator member; means for axially mounting a first multimode optical fiber and first light beam expanding and collimating means in said stator member; a generally frustoconical first bearing surface in said stator member, opening outwardly away from said first light beam expanding and collimating means; a rotor member having a second generally frustoconical bearing surface matable with said first bearing surface; means for axially mounting a second multimode optical fiber and second light beam expanding and collimating means in said rotor member; an end cap releasably secured to said stator member; and thrust bearing means between said end cap and said rotor member.
Claim 24
Dependent Claim
116 words
A fiber optic rotary joint for use with multimode optical fibers comprising: a stator member; means for axially mounting a first multimode optical fiber and first light beam expanding and collimating means in said stator member; a generally frustoconical first bearing surface in said stator member, opening outwardly away from said first light beam expanding and collimating means; a rotor member having a second generally frustoconical bearing surface matable with said first bearing surface; means for axially mounting a second multimode optical fiber and second light beam expanding and collimating means in said rotor member; an end cap releasably secured to said stator member; and thrust bearing means between said end cap and said rotor member.
Claim 25
Dependent Claim
158 words
A fiber optic rotary joint for use with single mode optical fibers, comprising; a stator member; first and second single mode optical fibers each having a core diameter for effectively propagating light in only a single mode; means interconnecting said first single mode optical fiber and a first light beam expanding and collimating means and for mounting said first fiber and said first expanding and collimating means in axial alignment in said stator member; a rotor member mounted to said stator member for rotation relative thereto; means interconnecting said second single mode optical fiber and a second light beam expanding and collimating means and for mounting said second fiber and said second expanding and collimating means in said rotor member; means establishing a sealed zone between said rotor and stator members, which zone includes an optical path between said first and second light beam expanding and collimating means; and an optically transmissive fluid contained within said sealed zone.
Claim 26
Dependent Claim
158 words
A fiber optic rotary joint for use with single mode optical fibers, comprising; a stator member; first and second single mode optical fibers each having a core diameter for effectively propagating light in only a single mode; means interconnecting said first single mode optical fiber and a first light beam expanding and collimating means and for mounting said first fiber and said first expanding and collimating means in axial alignment in said stator member; a rotor member mounted to said stator member for rotation relative thereto; means interconnecting said second single mode optical fiber and a second light beam expanding and collimating means and for mounting said second fiber and said second expanding and collimating means in said rotor member; means establishing a sealed zone between said rotor and stator members, which zone includes an optical path between said first and second light beam expanding and collimating means; and an optically transmissive fluid contained within said sealed zone.
References Cited (Backward Citations)
US4303330A
Cited
US4641915A
Cited
US4472052A
Cited
US4398791A
Cited
US4643521A
Cited
US4725116A
Cited
US4961622A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-08-12 | 1995-02-11 | 1995-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-12 | 1999-02-11 | 1999-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-12 | 2003-02-11 | 2003-08-13 | $7700.00 | Window Closed / Lapsed |