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US6323987B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Controlled multi-wavelength etalon

Assignee: Avago Technologies International Sales Pte Ltd
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Filing: 1999-05-14
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Granted: 2001-11-27
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Expires: 2019-05-14
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Abstract

Abstract A multi-wavelength etalon suitable for tuning and maintaining the operating frequency of a laser used in an optical communication system is disclosed. The communication system has a representative channel wavelength and a channel spacing. The etalon has a plurality of steps on one of the sides with a step size that is a fraction of the channel spacing. The nominal thickness of the etalon is chosen so that a transmission peak occurs at a wavelength substantially equal to the representative channel wavelength and a next peak occurs at the wavelength of an adjacent channel. The step size is a fraction of the channel separation and is substantially optimized so that a peak or trough in the transmission curve in the region of one step overlaps a steep portion of the transmission curve for one or more other steps.

Inventors

  • 👤 Dominic Paul Rinaudo
  • 👤 Walter Jeffrey Shakespeare
  • 👤 Richard Bendicks Bylsma

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 16:39
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/08; H01S3/08018; H01S3/08022; H01S3/08031; H01S3/08036; G; G01; G01J; G01J9/00; G01J9/02; G01J9/0246; H01S5/00; H01S5/06; H01S5/068; H01S5/0683; H01S5/0687; H01S5/0617

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 198 words
A multi-wavelength etalon comprising: a body which is transparent at least in a predetermined range of wavelengths and having first and second outwardly facing and opposing sides, the first side having a surface, the second side having a plurality of steps, each step having a surface substantially parallel to the surface of the first side, the surface of the first side and the surfaces of the steps being at least partially reflective; the first side and the surface of a particular one of the plurality of steps being separated by a thickness d; the difference between the thicknesses separating the first side and the surfaces of a pair of adjacent steps defining a step size Δd; the distance d being selected such that a transmission intensity curve of light transmitted through the etalon in the region of the particular step in response to light being applied substantially normal to the first side of the etalon is at a first relative peak when the applied light is of a first wavelength λ, is at a second adjacent relative peak when the applied light is of a second wavelength λ+cs; and wherein the step size Δd is less than cs.
Claim 2
Dependent Claim 198 words
A multi-wavelength etalon comprising: a body which is transparent at least in a predetermined range of wavelengths and having first and second outwardly facing and opposing sides, the first side having a surface, the second side having a plurality of steps, each step having a surface substantially parallel to the surface of the first side, the surface of the first side and the surfaces of the steps being at least partially reflective; the first side and the surface of a particular one of the plurality of steps being separated by a thickness d; the difference between the thicknesses separating the first side and the surfaces of a pair of adjacent steps defining a step size Δd; the distance d being selected such that a transmission intensity curve of light transmitted through the etalon in the region of the particular step in response to light being applied substantially normal to the first side of the etalon is at a first relative peak when the applied light is of a first wavelength λ, is at a second adjacent relative peak when the applied light is of a second wavelength λ+cs; and wherein the step size Δd is less than cs.
Claim 3
Dependent Claim 20 words
The etalon of claim 1 , wherein the reflectivity of the partially reflective surfaces is between approximately 5% and 95%.
Claim 4
Dependent Claim 17 words
The etalon of claim 2 , wherein the reflectivity of the partially reflective surfaces is approximately 40%.
Claim 5
Dependent Claim 86 words
The etalon of claim 1 , wherein peaks of transmission intensity curves indicating the magnitude of light transmitted through the etalon in the region of each of said plurality of steps in response to light being applied substantially normal to the first side of the etalon are offset relative to each other such that a peak in the transmission curve associated with one of said plurality of steps overlaps a relatively steeply sloped portion of a transmission curve associated with another of said plurality of steps.
Claim 6
Dependent Claim 41 words
The etalon of claim 4 , wherein the body has an index of refraction r and the step size Δd for each pair of adjacent steps is approximately equal to λ/(2*r*n), where n is the number of said plurality of steps.
Claim 7
Dependent Claim 54 words
The etalon of claim 1 , wherein the first wavelength λ corresponds to a wavelength of a representative optical communication channel in an optical communications system having a plurality of communication channels, and cs corresponds to the difference in wavelength between the representative channel wavelength and the wavelength of an adjacent optical communication channel.
Claim 8
Dependent Claim 250 words
A multi-wavelength air-gap etalon comprising: first and second body components separated by a gap and being transparent at least in a predetermined range of wavelengths; the first body component having a first outwardly facing side and a first inwardly facing side; the second body component having a second outwardly facing side and a second inwardly facing side; the first inwardly facing side having a plurality of steps, each step having a surface substantially parallel to the second inwardly facing side, the surface of the second inwardly facing side and the surfaces of the steps of the first inwardly facing side being at least partially reflective; the second inwardly facing side and the surface of a particular one of the plurality of steps of the first inwardly facing side being separated by a gap distance d; the difference between the gap distances separating the second side and the surfaces of a pair of adjacent steps of the first inwardly facing side defining a step size Δd; the gap distance d being selected such that a transmission intensity curve of light transmitted through the etalon in the region of the particular step in response to light being applied substantially normal to the second inwardly facing side of the etalon is at a first relative peak when the applied light is of a first wavelength λ, is at a second adjacent relative peak when the applied light is of a second wavelength λ+cs; and wherein the step size Δd is less than cs.
Claim 9
Dependent Claim 250 words
A multi-wavelength air-gap etalon comprising: first and second body components separated by a gap and being transparent at least in a predetermined range of wavelengths; the first body component having a first outwardly facing side and a first inwardly facing side; the second body component having a second outwardly facing side and a second inwardly facing side; the first inwardly facing side having a plurality of steps, each step having a surface substantially parallel to the second inwardly facing side, the surface of the second inwardly facing side and the surfaces of the steps of the first inwardly facing side being at least partially reflective; the second inwardly facing side and the surface of a particular one of the plurality of steps of the first inwardly facing side being separated by a gap distance d; the difference between the gap distances separating the second side and the surfaces of a pair of adjacent steps of the first inwardly facing side defining a step size Δd; the gap distance d being selected such that a transmission intensity curve of light transmitted through the etalon in the region of the particular step in response to light being applied substantially normal to the second inwardly facing side of the etalon is at a first relative peak when the applied light is of a first wavelength λ, is at a second adjacent relative peak when the applied light is of a second wavelength λ+cs; and wherein the step size Δd is less than cs.
Claim 10
Dependent Claim 178 words
A stepped etalon for use in stabilizing the wavelength of a laser light source producing light for use in an optical communication system, the optical communication system having a first communication channel wavelength of λ and a channel spacing of cs, the etalon comprising: a transparent body having an index of refraction r and first and second opposing sides, the first side having a surface, the second side having a plurality of steps, each step having a surface substantially parallel to the first side, the surface of the first side and the surfaces of the steps being partially reflective; the body having a nominal thickness d separating the first side and the surface of a particular one of the plurality of steps equal to approximately (λ 2 +λ*cs)/(2*r*cs); and the difference between the thicknesses separating the first side and the surfaces of a pair of adjacent steps defining a step size Δd, wherein the step size Δd for each pair of adjacent steps is approximately equal to λ/(2*r*n), where n is the number of said plurality of steps.
Claim 11
Dependent Claim 178 words
A stepped etalon for use in stabilizing the wavelength of a laser light source producing light for use in an optical communication system, the optical communication system having a first communication channel wavelength of λ and a channel spacing of cs, the etalon comprising: a transparent body having an index of refraction r and first and second opposing sides, the first side having a surface, the second side having a plurality of steps, each step having a surface substantially parallel to the first side, the surface of the first side and the surfaces of the steps being partially reflective; the body having a nominal thickness d separating the first side and the surface of a particular one of the plurality of steps equal to approximately (λ 2 +λ*cs)/(2*r*cs); and the difference between the thicknesses separating the first side and the surfaces of a pair of adjacent steps defining a step size Δd, wherein the step size Δd for each pair of adjacent steps is approximately equal to λ/(2*r*n), where n is the number of said plurality of steps.
Claim 12
Dependent Claim 30 words
The etalon of claim 8 , wherein the transparent body is comprised of a glass having an index of refraction approximately equal to 1.5 and d is substantially 2 mm.
Claim 13
Dependent Claim 19 words
The etalon of claim 9 , wherein the step size is less than or equal to approximately 258 nm.
Claim 14
Dependent Claim 16 words
The etalon of claim 8 , wherein the transparent body is comprised of SiO 2 .
Claim 15
Dependent Claim 20 words
The etalon of claim 9 , wherein the reflectivity of the partially reflective surfaces is between approximately 5% and 95%.
Claim 16
Dependent Claim 17 words
The etalon of claim 10 , wherein the reflectivity of the partially reflective surfaces is approximately 40%.
Claim 17
Dependent Claim 198 words
A multi-wavelength etalon comprising: a body which is transparent at least in a predetermined range of wavelengths and having first and second outwardly facing and opposing sides, the first side having a surface, the second side having a plurality of steps, each step having a surface substantially parallel to the surface of the first side, the surface of the first side and the surfaces of the steps being at least partially reflective; the first side and the surface of a particular one of the plurality of steps being separated by a thickness d; the difference between the thicknesses separating the first side and the surfaces of a pair of adjacent steps defining a step size Δd; the distance d being selected such that a reflection intensity curve of light reflected by the etalon in the region of the particular step in response to light being applied substantially normal to the first side of the etalon is at a first relative peak when the applied light is of a first wavelength λ, is at a second adjacent relative peak when the applied light is of a second wavelength λ+cs; and wherein the step size Δd is less than cs.
Claim 18
Dependent Claim 198 words
A multi-wavelength etalon comprising: a body which is transparent at least in a predetermined range of wavelengths and having first and second outwardly facing and opposing sides, the first side having a surface, the second side having a plurality of steps, each step having a surface substantially parallel to the surface of the first side, the surface of the first side and the surfaces of the steps being at least partially reflective; the first side and the surface of a particular one of the plurality of steps being separated by a thickness d; the difference between the thicknesses separating the first side and the surfaces of a pair of adjacent steps defining a step size Δd; the distance d being selected such that a reflection intensity curve of light reflected by the etalon in the region of the particular step in response to light being applied substantially normal to the first side of the etalon is at a first relative peak when the applied light is of a first wavelength λ, is at a second adjacent relative peak when the applied light is of a second wavelength λ+cs; and wherein the step size Δd is less than cs.

References Cited (Backward Citations)

US4170416A Cited
US5151585A Cited
US5289314A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2004-11-26 2005-05-28 2005-11-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-11-26 2009-05-28 2009-11-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-11-26 2013-05-28 2013-11-27 $7700.00 Window Closed / Lapsed

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