US4904035A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coupling device for guiding a light beam
Assignee: US Philips Corp
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Filing: 1988-08-17
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Granted: 1990-02-27
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Expires: 2008-08-17
Abstract
Abstract The invention relates to a coupling device for guiding a light beam sent through an end portion of an optical waveguide to the light-sensitive surface of a photodiode of a measuring instrument, in particular, an optical power meter, comprising an absorbing aperture associated with the end face of the optical waveguide, and having an aperture which widens conically towards the light-sensitive face of a photodiode, the aperture plate facing the end face of the optical waveguide with its side where the diameter of said aperture is smallest but slightly larger than the diameter of said end face of the optical waveguide. A device of simple construction and having substantially no reflection is obtained in that the light beam is directed straight to the light-sensitive surface of the photodiode, and the angular aperture β of the conical inner surface of the aperture plate is larger than 2 arc tan α max , tan α max being the maximum permissible numerical aperture (NA) of an optical waveguide to be connected in accordance with the specifications, of the measuring instrument.
Inventors
- 👤 Siegfried Heckmann
- 👤 Johannes Rybach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:46
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4204
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
155 words
A coupling device for guiding a light beam sent through an end portion of an optical waveguide to the light-sensitive surface of a photodiode of a measuring instrument comprising an absorbing aperture plate associated with the end face of the optical waveguide, and having an aperture which widens conically towards the light-sensitive face of a photodiode, the aperture plate facing the end face of the optical waveguide with its side where the diameter of said aperture is smallest but slightly larger than the diameter of said end face of the optical waveguide, where in the light beam is directed straight to the light-sensitive surface of the photodiode, and the angular aperture β of the conical inner surface of the aperture plate is larger than 2 arc tan α max , tan α max being the maximum permissible numerical aperture of an optical waveguide to be connected in accordance with the specifications of the measuring instrument.
Claim 2
Dependent Claim
155 words
A coupling device for guiding a light beam sent through an end portion of an optical waveguide to the light-sensitive surface of a photodiode of a measuring instrument comprising an absorbing aperture plate associated with the end face of the optical waveguide, and having an aperture which widens conically towards the light-sensitive face of a photodiode, the aperture plate facing the end face of the optical waveguide with its side where the diameter of said aperture is smallest but slightly larger than the diameter of said end face of the optical waveguide, where in the light beam is directed straight to the light-sensitive surface of the photodiode, and the angular aperture β of the conical inner surface of the aperture plate is larger than 2 arc tan α max , tan α max being the maximum permissible numerical aperture of an optical waveguide to be connected in accordance with the specifications of the measuring instrument.
Claim 3
Dependent Claim
58 words
A coupling device as claimed in claim 1, where in a distance a between the aperture, at the location of its smallest diameter d, and the surface of the light-sensitive layer of the photodiode, is selected in the range from 5R p ≧a≧1.7R p , R p being the outer radius of the light-sensitive surface of the photodiode.
Claim 4
Dependent Claim
90 words
A coupling device as claimed in claim 1 or 2 wherein a distance a between the aperture, at the location of its smallest diameter d, and the surface of the light-sensitive layer of the photodiode, is selected according to the equation: ##EQU2## wherein R kmax is the maximum core radius of an optical waveguide to be connected in accordance with the specifications of the measuring instrument and ρ is a dimensionless factor in the range from 1≧p≧0.8, and in that the diameter d ranges from 7R kmax ≧d≧2.5R kmax .
Claim 5
Dependent Claim
30 words
A device as claimed in claim 1 or 2, wherein the apex angle β of the conical aperture has a value in the range from 2.2α max ≧β≧2α max .
Claim 6
Dependent Claim
29 words
A coupling device as claimed in claim 1, characterized in that the apex angle β of the conical aperture has a value in the range from 2.2α max ≧β≧2αmax.
Claim 7
Dependent Claim
34 words
A device as claimed in claim 1, wherein the aperture cone extends over at least 40% of the distance a between the aperture plate at the location of its smallest diameter and the photodiode.
Claim 8
Dependent Claim
20 words
A device as claimed in claim 1, wherein the measuring instrument is dimensioned for a value tan α max =0.3-0.35.
Claim 9
Dependent Claim
14 words
A device as claimed in claim 2, wherein the distance a=2.5 to 3 mm.
Claim 10
Dependent Claim
17 words
A device as claimed in claim 1, wherein the aperture plate is integrated in the measuring instrument.
Claim 11
Dependent Claim
21 words
A device as claimed in claim 1, wherein the aperture plate forms part of a connector adaptor for connectorized optical waveguides.
Claim 12
Dependent Claim
27 words
A device as claimed in claim 1, wherein the distance between the aperture plate and the end face of the optical waveguide is less than 10 μm.
Claim 13
Dependent Claim
28 words
A device as claimed in claim 3, wherein the apex angle β of the conical aperture has a value in the range from 2.2α max ≧β≧2α max .
Claim 14
Dependent Claim
34 words
A device as claimed in claim 2, wherein the aperture cone extends over at least 40% of the distance a between the aperture plate at the location of its smallest diameter and the photodiode.
Claim 15
Dependent Claim
34 words
A device as claimed in claim 3, wherein the aperture cone extends over at least 40% of the distance a between the aperture plate at the location of its smallest diameter and the photodiode.
Claim 16
Dependent Claim
34 words
A device as claimed in claim 4, wherein the aperture cone extends over at least 40% of the distance a between the aperture plate at the location of its smallest diameter and the photodiode.
Claim 17
Dependent Claim
20 words
A device as claimed in claim 2, wherein the measuring instrument is dimensioned for a value tan α max =0.3-0.35.
Claim 18
Dependent Claim
20 words
A device as claimed in claim 3, wherein the measuring instrument is dimensioned for a value tan α max =0.3-0.35.
Claim 19
Dependent Claim
20 words
A device as claimed in claim 4, wherein the measuring instrument is dimensioned for a value tan α max =0.3-0.35.
Claim 20
Dependent Claim
20 words
A device as claimed in claim 6, wherein the measuring instrument is dimensioned for a value tan α max =0.3-0.35.
Claim 21
Dependent Claim
14 words
A device as claimed in claim 2, wherein the distance a=2.5 to 3 mm.
Claim 22
Dependent Claim
14 words
A device as claimed in claim 6, wherein the distance a=2.5 to 3 mm.
Claim 23
Dependent Claim
14 words
A device as claimed in claim 7, wherein the distance a=2.5 to 3 mm.
References Cited (Backward Citations)
US4826272A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-26 | 1993-08-28 | 1994-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-26 | 1997-08-28 | 1998-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-26 | 2001-08-28 | 2002-02-27 | $7700.00 | Window Closed / Lapsed |