US4982405A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coupled-cavity Q-switched laser
Assignee: Massachusetts Institute of Technology
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Filing: 1989-09-07
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Granted: 1991-01-01
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Expires: 2009-09-07
Abstract
Abstract A Q-switched laser having a gain medium disposed within a first cavity and a second cavity whose optical path length is adjustable such that the quality of the first resonant cavity is affected. One aspect of the invention is the changing of the physical path length of the second cavity so as to affect the reflectivity of a mirror common to both cavities as seen from the first cavity. Another aspect of the invention is the incorporation, within the second cavity, of a material whose refractive index or absorption coefficient can be varied by the application of an electric field, a magnetic field, a temperature change or an applied pressure.
Inventors
- 👤 John J. Zayhowski
- 👤 Aram Mooradian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:57
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/0627; H01S3/08; H01S3/081; H01S3/082; H01S3/10; H01S3/105; H01S3/106; H01S3/108; H01S3/0602; H01S3/0604; H01S3/08018; H01S3/08022; H01S3/08031; H01S3/102; H01S3/1067; H01S3/11; H01S3/1123; H01S3/1124; H01S3/115; H01S3/117
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
59 words
A Q-switched laser comprising a gain medium disposed within a first resonant cavity and a second resonant cavity disposed adjacent to the first resonant cavity, the optical path length of the second resonant cavity being adjustable such that the net gain of the first resonant cavity containing said gain medium is affected through optical interactions with the second cavity.
Claim 2
Dependent Claim
59 words
A Q-switched laser comprising a gain medium disposed within a first resonant cavity and a second resonant cavity disposed adjacent to the first resonant cavity, the optical path length of the second resonant cavity being adjustable such that the net gain of the first resonant cavity containing said gain medium is affected through optical interactions with the second cavity.
Claim 3
Dependent Claim
29 words
The Q-switched laser of claim 1 wherein the optical path length of the second resonant cavity is varied by changes in the physical length of the second resonant cavity.
Claim 4
Dependent Claim
32 words
The Q-switched laser of claim 1 wherein the optical path length of the second resonant cavity is varied by changing the index of refraction of a material within the second resonant cavity.
Claim 5
Dependent Claim
31 words
The Q-switched laser of claim 3 wherein said material within said second resonant cavity has an index of refraction which varies in response to an external stimulus applied to said material.
Claim 6
Dependent Claim
29 words
The Q-switched laser of claim 4 wherein the material within said second cavity comprises an electro-optical material whose index of refraction changes in response to an applied electric field.
Claim 7
Dependent Claim
13 words
The Q-switched laser of claim 5 wherein said electro-optical material is a semiconductor.
Claim 8
Dependent Claim
11 words
The Q-switched laser of claim 6 wherein said semiconductor is gallium-aluminum-arsenide.
Claim 9
Dependent Claim
12 words
The Q-switched laser of claim 6 wherein said semiconductor is cadmium sulfide.
Claim 10
Dependent Claim
13 words
The Q-switched laser of claim 5 wherein said electro-optical material is lithium niobate.
Claim 11
Dependent Claim
13 words
The Q-switched laser of claim 5 wherein said electro-optical material is potassium niobate.
Claim 12
Dependent Claim
37 words
The Q-switched laser of claim 4 wherein the material within said second resonant cavity comprises a non-linear optical material which changes its index of refraction in response to a light beam incident upon the non-linear optical material.
Claim 13
Dependent Claim
14 words
The Q-switched laser of claim 11 wherein said non-linear optical material is lithium niobate.
Claim 14
Dependent Claim
14 words
The Q-switched laser of claim 11 wherein said non-linear optical material is potassium niobate.
Claim 15
Dependent Claim
14 words
The Q-switched laser of claim 11 wherein said non-linear optical material is a semiconductor.
Claim 16
Dependent Claim
11 words
The Q-switched laser of claim 14 wherein said semiconductor is gallium-aluminum-arsenide.
Claim 17
Dependent Claim
12 words
The Q-switched laser of claim 14 wherein said semiconductor is cadmium sulfide.
Claim 18
Dependent Claim
31 words
The Q-switched laser of claim 4 wherein the material disposed within said second resonant cavity changes its index of refraction in response to a change in the temperature of the material.
Claim 19
Dependent Claim
25 words
The Q-switched laser of claim 4 wherein said material located within said second cavity changes its index of refraction in response to a magnetic field.
Claim 20
Dependent Claim
30 words
The Q-switched laser of claim 18 wherein said material located within said second cavity which changes its index of refraction in response to a magnetic field is a magnetic spinel.
Claim 21
Dependent Claim
30 words
The Q-switched laser of claim 18 wherein said material located within said second cavity which changes its index of refraction in response to a magnetic field is a magnetic garnet.
Claim 22
Dependent Claim
26 words
The Q-switched laser of claim 1 wherein said second resonant cavity comprises an electro-optical material whose absorption coefficient changes in response to an applied electric field.
Claim 23
Dependent Claim
18 words
The Q-switched laser of claim 21 wherein said electro-optical material comprises a semiconductor operated near its band edge.
Claim 24
Dependent Claim
23 words
The Q-switched laser of claim 1 wherein said second resonant cavity comprises an electro-optical material whose absorption coefficient changes in response to light.
Claim 25
Dependent Claim
18 words
The Q-switched laser of claim 23 wherein said electro-optical material comprises a semiconductor operated near its band edge.
Claim 26
Dependent Claim
29 words
The Q-switched laser of claim 1 wherein said second resonant cavity further comprises an external coupling mirror whose reflectivity changes in response to an external stimulus to the mirror.
Claim 27
Dependent Claim
30 words
The Q-switched laser of claim 25 wherein said external coupling mirror whose reflectivity changes in response to an external stimulus to the mirror comprises an etalon comprising an electro-optical material.
Claim 28
Dependent Claim
47 words
The Q-switched laser of claim 1 wherein the intensity of the light produced by the first cavity is changed by changing the optical path length of the second cavity such that the intensity of the light produced by the first cavity is diminished but not turned off.
Claim 29
Dependent Claim
59 words
A Q-switched laser comprising a gain medium disposed within a first resonant cavity and a second resonant cavity disposed adjacent to the first resonant cavity, the optical path length of the first resonant cavity being adjustable such that the net gain of the first resonant cavity containing said gain medium is affected through optical interactions with the second cavity.
Claim 30
Dependent Claim
59 words
A Q-switched laser comprising a gain medium disposed within a first resonant cavity and a second resonant cavity disposed adjacent to the first resonant cavity, the optical path length of the first resonant cavity being adjustable such that the net gain of the first resonant cavity containing said gain medium is affected through optical interactions with the second cavity.
Claim 31
Dependent Claim
68 words
A Q-switched laser comprising a gain medium disposed within a first resonant cavity and a second resonant cavity disposed adjacent to the first resonant cavity, between the first resonant cavity and an optical pump, the optical path length of the second resonant cavity being adjustable such that the net gain of the first resonant cavity containing said gain medium is affected through optical interactions with the second cavity.
Claim 32
Dependent Claim
68 words
A Q-switched laser comprising a gain medium disposed within a first resonant cavity and a second resonant cavity disposed adjacent to the first resonant cavity, between the first resonant cavity and an optical pump, the optical path length of the second resonant cavity being adjustable such that the net gain of the first resonant cavity containing said gain medium is affected through optical interactions with the second cavity.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-31 | 1994-07-02 | 1995-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-31 | 1998-07-02 | 1999-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-31 | 2002-07-02 | 2003-01-01 | $7700.00 | Window Closed / Lapsed |