EP0565261A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical devices
Assignee: BAE Systems Electronics Ltd
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Filing: 1993-03-22
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Granted: —
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Expires: 2013-03-22
Abstract
Abstract An optical device comprising a pair of facing semi-reflective layers (3, 5) forming a Fabry-Perot resonator wherein the spacing between the layers is slightly greater in a central region (9) of the resonator than in the surrounding area. As a result the divergence of light in an input beam applied to the device in the central region, and hence the linewidth of the transmission resonance of the device, is reduced.
Inventors
- 👤 William James Stewart
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 02:02
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/12; G01J3/26
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
75 words
An optical device comprising a pair of facing semi-reflective layers (3, 5) separated by a distance such as to form a Fabry-Perot resonator at optical frequencies, characterised in that said distance is greater in a region (9) where an input beam is applied to the device in operation than in an area surrounding said region (9) by an amount such as to enhance confinement of the output beam of said device to said region (9).
Claim 2
Dependent Claim
75 words
An optical device comprising a pair of facing semi-reflective layers (3, 5) separated by a distance such as to form a Fabry-Perot resonator at optical frequencies, characterised in that said distance is greater in a region (9) where an input beam is applied to the device in operation than in an area surrounding said region (9) by an amount such as to enhance confinement of the output beam of said device to said region (9).
Claim 3
Dependent Claim
24 words
A device according to Claim 1 wherein said distance reduces in a step to a smaller value at the edge of said region (9).
Claim 4
Dependent Claim
28 words
A device according to Claim 1 or Claim 2 wherein said distance in said region (9) is less than 1% greater than said distance in said surrounding area.
Claim 5
Independent Claim
20 words
A device according to any one of the preceding claims wherein said distance is substantially uniform throughout said region (9).
Claim 6
Independent Claim
18 words
A device according to any one of the preceding claims wherein said semi-reflective layers (3, 5) are parallel.
Claim 7
Independent Claim
22 words
A device according to any one of the preceding claims wherein said semi-reflective layers (3, 5) are separated by a semiconductor material.
Claim 8
Independent Claim
24 words
A device according to any one of Claims 1 to 5 wherein said semi-reflective layers (3, 5) are separated by a liquid crystal material.
Claim 9
Independent Claim
48 words
A device according to any one of the preceding claims wherein said resonator is formed on a light transmissive substrate (1) and said input beam is applied to the device from the substrate (1) in a direction substantially normal to the planes of said semi-reflective layers (3, 5).
Claim 10
Dependent Claim
35 words
An optical arrangement comprising two optical devices according to any one of the preceding claims, the Fabry-Perot resonators of the two devices being fabricated in close-spaced relationship so as to form a four-port optical coupler.
References Cited (Backward Citations)
JPS58225678A
Cited
JPH01204488A
Cited
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