US4665524A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mode locked laser light sources
Assignee: British Telecommunications PLC
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Filing: 1985-05-24
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Granted: 1987-05-12
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Expires: 2005-05-24
Abstract
Abstract A mode-locked laser light source, i.e. a light source in which resonant longitudinal modes of the laser cavity are synchronized in phase to produce a pulsed laser output, is provided with an optical phase-lock loop, to lock the optical output pulse train to the mode-locking radio frequency drive signal. The invention provides a highly stable laser source for light pulses of picoseconds duration.
Inventors
- 👤 David Cotter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:34
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/11; H01S3/1106; H01S3/1109; H01S3/106; H01S3/1068; H01S3/13; H01S3/136
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
82 words
A mode-locked laser light source comprising: a laser having a laser cavity, a radio frequency source of high spectral purity, means for mode-locking resonant longitudinal modes of the laser cavity when the mode-locking means is driven by a drive signal derived from an output signal of the radio frequency source, and optical phase-lock means including light detecting means and phase detecting means for detecting and locking respectively an optical output pulse train to a radio frequency signal derived from said output signal.
Claim 2
Dependent Claim
82 words
A mode-locked laser light source comprising: a laser having a laser cavity, a radio frequency source of high spectral purity, means for mode-locking resonant longitudinal modes of the laser cavity when the mode-locking means is driven by a drive signal derived from an output signal of the radio frequency source, and optical phase-lock means including light detecting means and phase detecting means for detecting and locking respectively an optical output pulse train to a radio frequency signal derived from said output signal.
Claim 3
Dependent Claim
38 words
A laser light source as claimed in claim 1 wherein a variable attentuation means is provided to control the magnitude of the drive signal and wherein the variable attenuation means is controlled by said optical phase lock means.
Claim 4
Dependent Claim
38 words
A laser light source as claimed in claim 1 wherein electronic phase shift means is provided to control the phase of the drive signal, and wherein the phase shift means is controlled by said optical phase lock means.
Claim 5
Dependent Claim
21 words
A laser light source as claimed in claim 1, wherein the laser cavity includes said mode-locking means which comprises acousto-optic modulator.
Claim 6
Dependent Claim
15 words
A light source according to claim 1 wherein said laser is a solid state laser.
Claim 7
Dependent Claim
14 words
A light source according to claim 1 wherein said laser is a gas laser.
Claim 8
Dependent Claim
17 words
A laser light source as claimed in claim 1 wherein said laser is a gain-modulated semiconductor laser.
Claim 9
Dependent Claim
28 words
A light source as claimed in claim 1 comprising said laser and a further laser, wherein said laser operates as a synchronous pump laser for the further laser.
Claim 10
Dependent Claim
15 words
A light source according to claim 8 wherein said further laser is a dye laser.
Claim 11
Dependent Claim
16 words
A light source according to claim 8 wherein said further laser is a colour centre laser.
Claim 12
Dependent Claim
19 words
A laser light source as claimed in claim 1 wherein said phase detector means comprises a double balanced mixer.
Claim 13
Independent Claim
48 words
A method of operating a mode-locked laser light source comprising the steps of mode locking a laser to the resonant longitudinal modes of its laser cavity, detecting an optical pulse train thereby generated, and phase-locking the optical pulse train to a radio frequency signal of high spectral purity.
Claim 14
Independent Claim
48 words
A method of operating a mode-locked laser light source comprising the steps of mode locking a laser to the resonant longitudinal modes of its laser cavity, detecting an optical pulse train thereby generated, and phase-locking the optical pulse train to a radio frequency signal of high spectral purity.
Claim 15
Dependent Claim
52 words
A mode-locking laser light source, comprising: a radio frequency source having a circuit of high spectral purity operating at a pre-determined operating frequency, means to control phase and/or magnitude of a radio frequency drive signal for mode-locking said light source, and optical phase lock means to control the drive signal control means.
Claim 16
Dependent Claim
52 words
A mode-locking laser light source, comprising: a radio frequency source having a circuit of high spectral purity operating at a pre-determined operating frequency, means to control phase and/or magnitude of a radio frequency drive signal for mode-locking said light source, and optical phase lock means to control the drive signal control means.
Claim 17
Dependent Claim
18 words
A circuit as claimed in claim 13, comprising further circuit means to stabilize the radio frequency drive signal.
Claim 18
Dependent Claim
21 words
A circuit as claimed in claim 13 wherein the phase lock means have a loop bandwidth of less than 10 kHz.
References Cited (Backward Citations)
GB1255807A
Cited
GB1321389A
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US3869680A
Cited
GB1495847A
Cited
US4044316A
Cited
US4485473A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-11 | 1990-11-10 | 1991-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-11 | 1994-11-10 | 1995-05-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-11 | 1998-11-10 | 1999-05-12 | $7700.00 | Window Closed / Lapsed |