Patent EP0117734A2 successfully refreshed from Google Patents.
EP0117734A2
Expired / Lapsed
EP
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Multicavity optical device and applications thereof
Assignee: AT&T Inc
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Filing: 1984-02-24
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Granted: —
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Expires: 2004-02-24
Abstract
Abstract A semiconductor laser comprising spaced apart optical cavities (3, 5) which are mutually optically coupled through cleaved mirror surfaces at facing ends of the cavities. Each cavity is provided with electrode mean (7, 9) whereby the optical characteristics of the laser can be tuned to provide a high intensity, singlefrequency mode light output. The frequency of the output mode can be shifted in precise amounts allowing use of the device in a frequency shift keying communications system. Also, greater stability of the light output is obtained by means of a feedback system (Fig. 20) utilizing certain detected characteristics of the output light.
Inventors
- 👤 Nils Anders Olsson
- 👤 Won-Tien Tsang
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 20:00
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/14; H01S3/00; H01S3/05; H01S3/08; H01S3/081; H01S3/082; H01S3/0823; H01S3/0826; H01S5/1021; H01S5/02; H01S5/026; H01S5/40; H01S5/4025
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
59 words
A semiconductor laser for generating a single mode radiant output comprising first (3) and second (5) spaced apart and mutually optically coupled cavity sections, CHARACTERIZED IN THAT said sections are optically coupled together though cleaved mirror surfaces, and means (I 1 , I 2 ) are provided for adjusting the refractive index of said sections relative to each other.
Claim 2
Dependent Claim
59 words
A semiconductor laser for generating a single mode radiant output comprising first (3) and second (5) spaced apart and mutually optically coupled cavity sections, CHARACTERIZED IN THAT said sections are optically coupled together though cleaved mirror surfaces, and means (I 1 , I 2 ) are provided for adjusting the refractive index of said sections relative to each other.
Claim 3
Dependent Claim
17 words
A laser as recited in claim 1 including means for changing the wavelength of the radiant output.
Claim 4
Dependent Claim
29 words
A laser as recited in claim 1 in which said first section comprises a diode and said adjusting means comprises means for adjusting the current through said first section.
Claim 5
Dependent Claim
25 words
A laser as recited in claim 1 further comprising (Fig. 5) a third cavity section optically coupled to one of the others of said sections.
Claim 6
Dependent Claim
17 words
A laser as recited in claim 4 in which said third section is biased as a photodetector.
Claim 7
Dependent Claim
33 words
A laser as recited in claim 5 further comprising means (Fig. 20) connected between said third section and said first and second sections to control the output from said first and second sections.
Claim 8
Dependent Claim
40 words
A laser as recited in claim 3 in which said second section comprises a diode, and including first means for biasing said first section with a pulsed current and second means for biasing said second section with a pulsed current.
Claim 9
Dependent Claim
21 words
A laser as recited in claim 7 further comprising photodetector means to detect the optical output from at least one section.
Claim 10
Dependent Claim
14 words
A laser as recited in claim 8 in which said detectors are wavelength sensitive.
Claim 11
Dependent Claim
36 words
A laser as recited in claim 1 in which said first and second sections each includes an active layer, said sections being twisted with respect to each other about an axis formed by said active layers.
Claim 12
Dependent Claim
30 words
A layer as recited in claim 1 further comprising an external optical cavity, said first and second sections being in and optically aligned with respect to said external optical cavity.
Claim 13
Dependent Claim
22 words
A laser as recited in claim 1 in which at least one of said mirror surfaces is coated with a thin film.
Claim 14
Dependent Claim
18 words
A laser as recited in claim 3 in which said means for adjusting comprises means for adjusting bias.
Claim 15
Dependent Claim
51 words
A laser as recited in claim 3 including means for measuring at least one characteristic of the output from one of said sections with respect to the current through one of said sections; and feedback means using said at least one characteristic to maintain said output at a desired spectral value.
Claim 16
Dependent Claim
32 words
A laser as recited in claim 14 in which said at least one charactristic comprises the first derivative of the light output intensity with respect to the current through said only section.
Claim 17
Dependent Claim
22 words
A laser as recited in claim 15 in which said feedback means maintains said first derivative at a value of approximately zero.
Claim 18
Dependent Claim
33 words
A laser as recited in claim 16 in which said feedback means maintains said value of approximately zero at a local maximum in the light output power versus one section current charcteristic curve.
Claim 19
Dependent Claim
19 words
A laser as recited in claim 17 further comprising means for superimposing a modulating current through said one section.
Claim 20
Dependent Claim
19 words
A laser as recited in claim 14 in which said at least one characteristic comprises the light output intensity.
Claim 21
Dependent Claim
30 words
A laser as recited in claim 19 in which said feedback means maintains said characteristic at a local maximum in the light output power versus one section current characteristic curve.
References Cited (Backward Citations)
No citation records indexed.
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