Patent US3668420A successfully refreshed from Google Patents.
US3668420A
Expired / Lapsed
US
⏱️ 0.0 years remaining
1.5 micron raman laser
Assignee: International Business Machines Corp
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Filing: 1970-09-25
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Granted: 1972-06-06
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Expires: 1990-09-25
Abstract
Abstract A laser system which emits Raman-stokes radiation in the 1.5 micron (eye-safe) region is achieved by directing a Q-switched 1.06 micron giant pulse beam through a Raman-active medium which has a Raman frequency shift of around 3000 cm 1. The Q-switch is a saturable absorber dye from the class of bivalent transition metal dithiene complexes.
Inventors
- 👤 James T Vanderslice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:06
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/30; H01S3/305; H01S3/10; H01S3/11; H01S3/1123; H01S3/113
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
12 words
The apparatus of claim 1 wherein the Raman active medium is methane.
Claim 2
Dependent Claim
12 words
The apparatus of claim 1 wherein the Raman active medium is deuterium.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1 wherein the laser source of 1.06 microns is a Nd 3-glass rod.
Claim 4
Dependent Claim
16 words
The apparatus of claim 1 wherein the laser source of 1.06 microns is a Nd-YAG rod.
Claim 5
Dependent Claim
14 words
The apparatus of claim 1 wherein the dithiene complex has the following general formula:
Claim 6
Dependent Claim
19 words
The apparatus of claim 6 wherein the transition metal is selected from the group consisting of nickel and platinum.
Claim 7
Dependent Claim
14 words
The apparatus of claim 1 wherein the dithiene complex has the following general formula:
Claim 8
Dependent Claim
19 words
The apparatus of claim 8 wherein the transition metal is selected from the group consisting of nickel and platinum.
Claim 9
Dependent Claim
11 words
The apparatus of claim 9 wherein the dithiene complex is bis-(4-dimethylaminodithiobenzil)-nickel.
Claim 10
Dependent Claim
173 words
A compact Raman laser which emits radiation at 1.5 microns comprising: a source of laser radiation at 1.06 microns disposed within a first resonant cavity, one end of the cavity being partially transmitting, for emitting giant pulses; a solution of bis-(4-dimethylaminodithiobenzil)-nickel for Q-switching the source of laser radiation; pumping means coupled to the 1.06-micron source for exciting the source; a concentric resonant cavity formed by a pair of concave reflectors aligned along the optical path of the first resonant cavity, the length of the concentric resonant cavitY, being less than around 5 cm, the square root of the product of the reflectivities, R, at 1.5 microns of the concave reflectors being determined by the relationship: tp L/c(1-R) where tp is the photon lifetime within the concentric resonant cavity, L is the length of the concentric resonant cavity, and c is the speed of light; and a Raman-active medium comprising methane gas disposed within the concentric resonant cavity, the methane being stimulated to emit pulses of radiation at 1.54 microns by the giant pulses.
Claim 11
Dependent Claim
19 words
A compact Raman laser as in claim 11 wherein the source of 1.06 microns is a Nd 3-glass rod.
Claim 12
Dependent Claim
18 words
A compact Raman laser as in claim 11 wherein the source of 1.06 microns is a Nd-YAG rod.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |