Patent EP0564098A2 successfully refreshed from Google Patents.
EP0564098A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Variable spectral width multiple pass optical noise source
Assignee: HP Inc
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Filing: 1993-03-04
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Granted: —
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Expires: 2013-03-04
Abstract
Abstract An apparatus for creating an optical noise of a predetermined bandwidth uses an optical amplifier (2,20,50) which amplifies optical noise components and produces unpolarized optical noise by spontaneous emission, a mirror (32,52,98) to reflect the optical noise components back to the optical amplifier (2,20,50) and a filter (4,32,34,56,80) that filters out optical noise components outside the predetermined optical bandwidth. The filter (4,32,-34,56,80) is located so that optical noise components passed by the filter are amplified in the optical amplifier (2,20,50) during an additional amplification. Optionally, a pollarizer and Faraday rotator (30,54,96) are used in the apparatus. The optical noise created in the optical amplifier is polarized in the polarizer (34,36,58,60,84,100) after 2 amplifications, rotated in the Faraday rotator (30,54,96) then is amplified two more times before leaving the apparatus.
Inventors
- 👤 Douglas M. Baney
- 👤 Wayne V. Sorin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 20:27
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06795; H01S3/06708; H01S3/06712; Y; Y10; Y10S; Y10S372/00; Y10S372/703
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
127 words
An apparatus for creating optical noise of a predetermined bandwidth comprising: an amplifying means (2,20,50) in an optical path for amplifying optical noise components, said amplifying means (2,20,50) including means for producing unpolarized optical noise by spontaneous emission; reflecting means (6,32,52,98) in the optical path for reflecting the optical noise produced by the amplifying means (2,20,50) to back to the amplifying means (2,20,50) for at least one additional amplification; filter means (4,32,34,56,80) for filtering out optical noise components outside the predetermined optical bandwidth and for passing optical noise components within the predetermined optical bandwidth, wherein said filter means (4,32,34,56,80) is located in said optical path so that optical noise components passed by the filter means (4,32,34,56,80) are amplified by the amplifying means (2,20,50) during an additional amplification.
Claim 2
Dependent Claim
200 words
The apparatus of claim 1, further comprising: a polarizing means (36,34,84,100) located in said optical path on the opposite side of said amplifying means (20) from said reflecting means (32,98) for polarizing the optical noise components after said components have been amplified a second time, wherein said polarizing means (34,36,84,100) passes optical noise components of a first polarization to an output and reflects optical noise components of a second polarization toward the amplifying means (20) for a third amplification; a Faraday rotator (30,96) in said optical path located between said amplifying means (20) and said reflecting means (32,98) for rotating the polarization of the thrice-amplified optical noise component of the second polarization to a third polarization so that the thrice-amplified optical noise component of the third polarization is reflected by the reflecting means (32,98) back to the Faraday rotator (30,96), and for rotating the thrice-amplified optical noise component of the third polarization to the first polarization, so that the amplifier amplifies the thrice-amplified optical noise component of the first polarization of four-times-amplified optical noise components of a first polarization and so that the polarizing means (34,36,84,100) passes the four-times-amplified optical noise components of the first polarization to the output (40,102).
Claim 3
Dependent Claim
54 words
The apparatus of claim 2, wherein the filter means (80) is a transmissive filter located in the optical path between the amplifying means (93) and polarizing means (84,100), and wherein said transmissive filter allows optical noise components within the predetermined bandwidth to pass, but blocks the optical noise components outside the predetermined optical bandwidth.
Claim 4
Dependent Claim
35 words
The apparatus of claim 2, wherein the polarizing means (34,36,84,100) comprises a polarizing beamsplitter (84,36) and a second reflecting means (34,100) for reflecting optical noise components of a second polarization toward the amplifying means (2,20,50).
Claim 5
Independent Claim
40 words
The apparatus of any preceding claim, wherein the reflecting means and the filter means comprise a reflective filter (32), wherein said reflective filter reflects optical noise within the predetermined bandwidth and does not reflect optical noise outside the predetermined bandwidth.
Claim 6
Independent Claim
27 words
The apparatus of any preceding claim, wherein the amplifying means (2,20,50) comprises a pumping laser (25,94), a wavelength division multiplexer (24,92) and a doped amplifying fibre (22,90).
Claim 7
Dependent Claim
234 words
The apparatus of claim 1, further comprising: a polarizing means (58,60) located in said optical path on the opposite side of said amplifying means (2,50) from said reflecting means (6,52) for polarizing the optical noise components after said components have been amplified a second time, wherein said polarizing means (58,60) passes optical noise components of a first polarization to an output and reflects optical noise components of a second polarization toward the amplifying means (50) for a third amplification; a Faraday rotator (54) in said optical path located between said polarizing means (58,60) and said amplifying means (50) for rotating the polarization of the optical noise, wherein the Faraday rotator (54) rotates the polarization of the twice-amplified optical noise components of the second polarization to a third polarization before the amplifying means (50) amplifies the twice-amplified optical noise components of the third polarization during the third amplification, the reflecting means (52) reflects the thrice-amplified optical noise components of the third polarization back to the amplifying means (50) and the amplifying means (50) amplifies the thrice-amplified optical noise components of the third polarization to create four-times-amplified optical noise components of the third polarization, and wherein said Faraday optical rotator rotates the polarization of the four-times-amplified optical noise components from the third polarization to the first polarization so that the polarizing means (58,60) passes the four-times-amplified optical noise components of the first polarization to the output.
Claim 8
Independent Claim
84 words
A method for creating optical noise of a predetermined bandwidth, said method comprising the steps of: (a) creating an unpolarized optical noise by spontaneous emission; (b) thereafter, amplifying the optical noise in an amplifying means (2,20,50); (c) reflecting the amplified optical noise components back towards the amplifying means (2,20,50): (d) filtering out the optical noise components outside the predetermined bandwidth and passing optical noise components within the predetermined bandwidth; and (e) thereafter, amplifying the filtered optical noise components that are passed in step (d).
Claim 9
Dependent Claim
162 words
The method of claim 8, with the additional steps of: polarizing the optical noise components so that optical noise components of a first polarization are passed to an output and optical noise components of a second polarization are caused to travel towards the amplifying means (20) wherein twice-amplified optical noise components of the second polarization are caused to return to the amplifying means (20); amplifying the twice-amplified optical noise components of the second polarization to thrice-amplified optical components of the second polarization; rotating the polarization of the thrice-amplified optical noise components of the second polarization to a third polarization; reflecting the thrice-amplified optical noise components of the third polarization back toward the amplifying means (20); rotating the thrice-amplified optical noise components of the third polarization to the first polarization; amplifying the thrice-amplified optical noise components of the first polarization to four-times-amplified optical noise components of the first polarization; and passing the four-times-amplified optical noise components of the first polarization to the output.
Claim 10
Dependent Claim
163 words
The method of claim 8, with the additional steps of: polarizing the optical noise components so that optical noise components of a first polarization are passed to an output and optical noise components of a second polarization are caused to travel towards the amplifying means (50) wherein twice-amplified optical noise components of the second polarization are caused to be travel to the amplifying means (50); rotating the polarization of the twice-amplified optical noise components of the second polarization to a third polarization; amplifying the twice-amplified optical noise components of the third polarization to thrice-amplified optical components of the third polarization; reflecting the thrice-amplified optical noise components of the third polarization back towards the amplifying means (50); amplifying the thrice-amplified optical noise components of the third polarization to four-times-amplified optical noise components of the third polarization; rotating the four-times-amplified optical noise components of the third polarization to the first polarization; and passing the four-times-amplified optical noise components of the first polarization to the output.
References Cited (Backward Citations)
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