US4896326A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Peak power fluctuations in optical pulse compression
Assignee: Newport Corp USA
•
Filing: 1988-02-03
•
Granted: 1990-01-23
•
Expires: 2008-02-03
Abstract
Abstract Fluctuations in input intensity and pulsewidth affect the frequency doubled output pulse of a fiber grating optical pulse compressor in a compressed, continuous-wave, mode-locked Nd:YAG laser system. An optimized intensity servo system greatly reduces these fluctuations and results in as much as 50 dB noise reduction at low frequencies. Fluctuations in either input intensity or pulsewidth are corrected by changing the input intensity by means of the servo system.
Inventors
- 👤 James D. Kafka
- 👤 Thomas M. Baer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:51
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/005; H01S3/0057
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
124 words
Apparatus for stabilizing the frequency doubled output of a frequency doubler optically connected to a pulse compressor which is optically connected to and driven by a cw mode locked laser source producing laser pulses which are passed through the compressor and from the compressor through the frequency doubler, comprising: intensity measurement means following the frequency doubler for measuring the intensity of the frequency doubled output and producing an intensity measurement signal related thereto; controller means connected to the intensity measurement means for producing a drive signal in response to the intensity measurement signal; intensity adjustment means connected to the controller means and to the laser source for adjusting the intensity of the laser pulses from the laser source in response to the drive signal.
Claim 2
Dependent Claim
124 words
Apparatus for stabilizing the frequency doubled output of a frequency doubler optically connected to a pulse compressor which is optically connected to and driven by a cw mode locked laser source producing laser pulses which are passed through the compressor and from the compressor through the frequency doubler, comprising: intensity measurement means following the frequency doubler for measuring the intensity of the frequency doubled output and producing an intensity measurement signal related thereto; controller means connected to the intensity measurement means for producing a drive signal in response to the intensity measurement signal; intensity adjustment means connected to the controller means and to the laser source for adjusting the intensity of the laser pulses from the laser source in response to the drive signal.
Claim 3
Dependent Claim
14 words
The apparatus of claim 1 wherein the intensity adjustment means is an acousto-optic shutter.
Claim 4
Dependent Claim
13 words
The apparatus of claim 1 wherein the intensity measurement means is a photodiode.
Claim 5
Dependent Claim
135 words
A pulse compressed laser system with reduced noise from laser intensity and pulsewidth fluctuations, comprising: a cw modelocked laser source producing pulses of a preselected intensity; a pulse compressor optically aligned with the laser source for receiving and transmitting laser pulses to produce compressed pulses; a frequency doubler optically aligned with the pulse compressor to frequency double the compressed pulses; intensity measurement means following the frequency doubler for measuring the intensity of the frequency doubler output and producing an intensity measurement signal related thereto; controller means connected to the intensity measurement means for producing a drive signal in response to the intensity measurement signal; intensity adjustment means connected to the controller means and to the laser source for adjusting the intensity of the laser pulses from the laser source in response to the drive signal.
Claim 6
Dependent Claim
135 words
A pulse compressed laser system with reduced noise from laser intensity and pulsewidth fluctuations, comprising: a cw modelocked laser source producing pulses of a preselected intensity; a pulse compressor optically aligned with the laser source for receiving and transmitting laser pulses to produce compressed pulses; a frequency doubler optically aligned with the pulse compressor to frequency double the compressed pulses; intensity measurement means following the frequency doubler for measuring the intensity of the frequency doubler output and producing an intensity measurement signal related thereto; controller means connected to the intensity measurement means for producing a drive signal in response to the intensity measurement signal; intensity adjustment means connected to the controller means and to the laser source for adjusting the intensity of the laser pulses from the laser source in response to the drive signal.
Claim 7
Dependent Claim
14 words
The laser system of claim 4 wherein the laser source is a Nd:YAG laser.
Claim 8
Dependent Claim
32 words
The laser system of claim 4 wherein the pulse compressor is a fiber optic grating compressor comprising a single mode optical fiber whose output is passed through a double pass grating pair.
Claim 9
Dependent Claim
13 words
The laser system of claim 4 wherein the doubler is a KTP crystal.
Claim 10
Dependent Claim
46 words
The laser system of claim 4 wherein the laser source is a Nd:YAG laser, the pulse compressor is a fiber optic grating compressor comprising a single mode optical fiber whose output is passed through a double pass grating pair, and the doubler is a KTP crystal.
Claim 11
Dependent Claim
15 words
The laser system of claim 4 wherein the intensity adjustment means is an acousto-optic shutter.
Claim 12
Dependent Claim
14 words
The laser system of claim 4 wherein the intensity measurement means is a photodiode.
Claim 13
Dependent Claim
24 words
The laser system of claim 8 wherein the intensity adjustment means is an acousto-optic shutter positioned between the laser source and the pulse compressor.
Claim 14
Independent Claim
77 words
A method of reducing the effects of fluctuations in input intensity and pulsewidth on frequency doubled output pulses from a frequency doubler following an optical pulse compressor, comprising: measuring the intensity of frequency doubled output pulses from the frequency doubler following the pulse compressor; comparing the measured intensity to a selected intensity to determine a difference; adjusting the input intensity of input pulses to the optical pulse compressor in response to the difference to reduce the difference.
Claim 15
Independent Claim
77 words
A method of reducing the effects of fluctuations in input intensity and pulsewidth on frequency doubled output pulses from a frequency doubler following an optical pulse compressor, comprising: measuring the intensity of frequency doubled output pulses from the frequency doubler following the pulse compressor; comparing the measured intensity to a selected intensity to determine a difference; adjusting the input intensity of input pulses to the optical pulse compressor in response to the difference to reduce the difference.
Claim 16
Dependent Claim
22 words
The method of claim 12 wherein the step of adjusting the input intensity comprises acousto-optically modulating pulses input into the pulse compressor.
Claim 17
Dependent Claim
38 words
The method of claim 12 wherein the step of measuring the intensity of frequency doubled output pulses from the frequency doubler following the pulse compressor comprises inputting a portion of the frequency doubled output pulses into a photodiode.
References Cited (Backward Citations)
US3586997A
Cited
US3713042A
Cited
US4221960A
Cited
US4329569A
Cited
JPS59107331A
Cited
US4635263A
Cited
JPS61196128A
Cited
US4646308A
Cited
US4764930A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-22 | 1993-07-24 | 1994-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-22 | 1997-07-24 | 1998-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-22 | 2001-07-24 | 2002-01-23 | $7700.00 | Window Closed / Lapsed |