US4885752A
Expired / Lapsed
US
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Crystal modulated laser with improved resonator
Assignee: Raytheon Co
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Filing: 1988-03-28
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Granted: 1989-12-05
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Expires: 2008-03-28
Abstract
Abstract The laser (10) has a crystal modulator (22) located at one end (16) of the laser gain medium (12) opposite the end (14) to which the total reflector or grating (18) is attached. The outcoupler (28) is spaced a predetermined nonzero distance apart from the edge (30) of the crystal (22). The spacing (d) is selected to overcome and compensate for distortions caused by thermal lensing effects in the crystal (22).
Inventors
- 👤 Kuei-Ru Chien
- 👤 Kin-Kwok Hui
- 👤 H. Dean Stovall
- 👤 John H. S. Wang
- 👤 Albert J. Lamm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:16
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/107; H01S3/05; H01S3/08; H01S3/08072
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
136 words
A crystal modulated laser having pumping means for imparting a given amount of energy per unit time into a medium, comprising: a laser gain medium having first and second ends; a first reflecting means positioned generally adjacent said first end; an outcoupler reflecting means positioned generally adjacent and spaced from said second end; a crystal modulator positioned generally adjacent said second end and between said second end and said outcoupler reflecting means; said crystal modulator being receptive of laser light and being heated thereby, the heating causing thermal lensing in said crystal modulator; and said outcoupler reflecting means being spaced apart from said crystal modulator by a predetermined distance for substantially compensating for said thermal lensing in said crystal, said predetermined distance being a function of the energy imparted per unit time by said pumping means.
Claim 2
Dependent Claim
136 words
A crystal modulated laser having pumping means for imparting a given amount of energy per unit time into a medium, comprising: a laser gain medium having first and second ends; a first reflecting means positioned generally adjacent said first end; an outcoupler reflecting means positioned generally adjacent and spaced from said second end; a crystal modulator positioned generally adjacent said second end and between said second end and said outcoupler reflecting means; said crystal modulator being receptive of laser light and being heated thereby, the heating causing thermal lensing in said crystal modulator; and said outcoupler reflecting means being spaced apart from said crystal modulator by a predetermined distance for substantially compensating for said thermal lensing in said crystal, said predetermined distance being a function of the energy imparted per unit time by said pumping means.
Claim 3
Dependent Claim
41 words
The laser of claim 1 wherein said distance is the distance d, given by ##EQU3## where f≅(2.1×10 -4 ×Pc×L) -1 cm z=14.5 cm L=the length of said crystal modulator in cm Pc=the intracavity circulating power of said laser light in watts.
Claim 4
Dependent Claim
13 words
The laser of claim 1 wherein said crystal modulator comprises a CdTe crystal.
Claim 5
Dependent Claim
14 words
The laser of claim 1 wherein said first reflecting means comprises a total reflector.
Claim 6
Dependent Claim
13 words
The laser of claim 1 wherein said first reflecting means comprises a grating.
Claim 7
Dependent Claim
14 words
The laser of claim 1 wherein said outcoupler reflecting means comprises a plane mirror.
Claim 8
Dependent Claim
14 words
The laser of claim 1 wherein said outcoupler reflecting means comprises a concave mirror.
Claim 9
Dependent Claim
14 words
The laser of claim 1 wherein said outcoupler reflecting means comprises a convex mirror.
Claim 10
Dependent Claim
17 words
The laser of claim 1 wherein said outcoupler reflecting means comprises a lens and reflecting mirror combination.
Claim 11
Independent Claim
182 words
A method of operating a crystal modulated laser having pumping means for imparting a given amount of energy per unit time into a medium, comprising: using a laser gain medium to produce laser light; placing a total reflector means at one end of said laser gain medium in the path of said laser light; placing an outcoupler means at the other end of said laser gain medium in the path of said laser light; placing a crystal modulator in the path of said laser light between the total reflector at one end of the laser gain medium and the outcoupler means at the other end of the laser gain medium, said crystal modulator being heated by said laser light, the heating causing thermal lensing in said crystal modulator; and adjusting the position of said outcoupler means relative to said crystal modulator by disposing said outcoupler means a predetermined distance spaced from said crystal modulator, said predetermined distance being a function of the energy imparted per unit time by said pumping means to substantially compensate for said thermal lensing in said crystal modulator.
Claim 12
Independent Claim
182 words
A method of operating a crystal modulated laser having pumping means for imparting a given amount of energy per unit time into a medium, comprising: using a laser gain medium to produce laser light; placing a total reflector means at one end of said laser gain medium in the path of said laser light; placing an outcoupler means at the other end of said laser gain medium in the path of said laser light; placing a crystal modulator in the path of said laser light between the total reflector at one end of the laser gain medium and the outcoupler means at the other end of the laser gain medium, said crystal modulator being heated by said laser light, the heating causing thermal lensing in said crystal modulator; and adjusting the position of said outcoupler means relative to said crystal modulator by disposing said outcoupler means a predetermined distance spaced from said crystal modulator, said predetermined distance being a function of the energy imparted per unit time by said pumping means to substantially compensate for said thermal lensing in said crystal modulator.
Claim 13
Dependent Claim
41 words
The method of claim 10 wherein said distance is the distance d, given by ##EQU4## where f≅(2.1×10 -4 ×Pc×L) -1 cm z=14.5 cm L=the length of said crystal modulator in cm Pc=the intracavity circulating power of said laser light in watts.
Claim 14
Dependent Claim
39 words
The method of claim 10 further comprising spacing said total reflector means a second distance from said laser gain medium, said distance and said second distance combined being selected to substantially compensate for said thermal lensing in said crystal.
Claim 15
Dependent Claim
10 words
The method of claim 10 wherein the outcoupler is nonflat.
Claim 16
Dependent Claim
26 words
The method of claim 10 wherein the outcoupler is in the form of a combined lens and reflecting mirror in the path of said laser light.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-04 | 1993-06-05 | 1993-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-04 | 1997-06-05 | 1997-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-04 | 2001-06-05 | 2001-12-05 | $7700.00 | Window Closed / Lapsed |