US6002697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diode pumped laser with frequency conversion into UV and DUV range
Assignee: Lambda Physik AG
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Filing: 1998-08-24
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Granted: 1999-12-14
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Expires: 2018-08-24
Abstract
Abstract A solid state laser is provided including a rare earth-doped YAG, YLF, YVO, GSGG, YALO or GdVO oscillator crystal, at least one laser diode pumping source, a Q-switch short pulse generator, a frequency doubling stage and frequency quadrupling or quintupling stages. The frequency quadrupling or quintupling stages include a nonlinear optical crystal such as CLBO, BBO or LBO built into a housing. The housing is sealed off to prevent external moisture and other atmospheric impurities from accessing the crystal at its interior. The housing interior is configured for purging with one or more external inert gases or dry air through valve controls. The housing is equipped with a mechanism for controlling the temperature of the interior of the housing, and consequently for controlling the temperature of the crystal. The temperature controlling mechanism enables heating and cooling of the crystal, as well as maintaining the crystal at a constant selected temperature. The housing includes optical windows transparent for input and output radiation.
Inventors
- 👤 Sergei V. Govorkov
- 👤 Uwe Stamm
- 👤 Wolfgang V. Zschocka
- 👤 Thomas Schroder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:39
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/3501; H; H01; H01S; H01S3/00; H01S3/005; H01S3/0092; G02F1/3505; G02F1/353; G02F1/354; G02F1/3544; G02F1/3546; G02F1/37; H01S3/10; H01S3/11; H01S3/1123; H01S3/115; H01S3/117; H01S3/14; H01S3/16; H01S3/1601; H01S3/1603; H01S3/163; H01S3/164; H01S3/1643
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
67 words
A solid state laser system, comprising: a laser active medium for emitting a beam at a characteristic frequency; a resonator; one or more frequency conversion stages including a housing containing and controlling an environment around a nonlinear optical crystal, said housing including means for optically accessing said crystal and means for fluidly accessing said environment; and means for controlling the temperature of said crystal within said housing.
Claim 2
Dependent Claim
67 words
A solid state laser system, comprising: a laser active medium for emitting a beam at a characteristic frequency; a resonator; one or more frequency conversion stages including a housing containing and controlling an environment around a nonlinear optical crystal, said housing including means for optically accessing said crystal and means for fluidly accessing said environment; and means for controlling the temperature of said crystal within said housing.
Claim 3
Dependent Claim
15 words
The laser system of claim 1, wherein said fluid access means is a valve-controlled port.
Claim 4
Dependent Claim
25 words
The laser system of claim 1, wherein at least one of said stages includes a nonlinear optical crystal for at least quadrupling said characteristic frequency.
Claim 5
Dependent Claim
24 words
The laser system of claim 1, wherein said fluid access means provides an avenue for fluids to flow into and out of said housing.
Claim 6
Dependent Claim
16 words
The laser system of claim 1, wherein said housing is purgeable by said fluid access means.
Claim 7
Dependent Claim
29 words
The laser system of claim 5, wherein said gas is selected from the group of gases including nitrogen, dry air and inert gases such as argon, helium and neon.
Claim 8
Dependent Claim
24 words
The laser system of claim 5, wherein said gas is dry air and said dry air is circulated for removing moisture from said environment.
Claim 9
Dependent Claim
16 words
The laser system of claim 1, wherein said housing is evacuatable by said fluid access means.
Claim 10
Dependent Claim
42 words
The laser system of claim 1, wherein said means for optically accessing said crystal is a first window aligned at Brewster's angle to the beam entering said housing and a second window aligned at Brewster's angle to the beam exiting said housing.
Claim 11
Dependent Claim
30 words
The laser system of claim 9, wherein the frequency of the beam exiting the housing is greater by an integral amount than the frequency of the beam entering the housing.
Claim 12
Dependent Claim
32 words
The laser system of claim 9, wherein said second window comprises a material selected from the group of materials consisting of CaF 2 , MgF 2 , crystalline quartz and fused silica.
Claim 13
Dependent Claim
20 words
The laser system of claim 1, said crystal is on an adjustable holder for adjusting an orientation of said crystal.
Claim 14
Dependent Claim
20 words
The laser system of claim 12, wherein a temperature of said holder is adjusted and controlled by a temperature controller.
Claim 15
Dependent Claim
20 words
The laser system of claim 1, wherein said fluid access means is used to prevent moisture from accessing said crystal.
Claim 16
Dependent Claim
18 words
The laser system of claim 1, wherein moisture is removed from said housing by said fluid access means.
Claim 17
Dependent Claim
15 words
The laser system of claim 1, wherein the temperature is controllable to within 0.1° C.
Claim 18
Dependent Claim
14 words
The laser system of claim 16, wherein the stabilized temperature is approximately 100° C.
Claim 19
Dependent Claim
29 words
The laser system of claim 1, wherein said means for adjusting and controlling the temperature includes a feedback loop and a controller receiving temperature information from a temperature sensor.
Claim 20
Dependent Claim
27 words
The laser system of claim 1, wherein said means for adjusting and controlling the temperature includes a feedback loop and a controller receiving optical output power information.
Claim 21
Dependent Claim
38 words
The laser system of claim 1, wherein said means for adjusting and controlling the temperature includes a feedback loop and a controller receiving a signal from a dual photosensor measuring angular deviation of the beam exiting the housing.
Claim 22
Dependent Claim
38 words
A nonlinear optical crystal housing containing and controlling an environment around a nonlinear optical crystal, comprising: a pair of optical windows; at least one fluid access port; and means for adjusting and controlling a temperature of the environment.
Claim 23
Dependent Claim
38 words
A nonlinear optical crystal housing containing and controlling an environment around a nonlinear optical crystal, comprising: a pair of optical windows; at least one fluid access port; and means for adjusting and controlling a temperature of the environment.
Claim 24
Dependent Claim
22 words
The nonlinear optical crystal housing of claim 21, said crystal is on an adjustable holder for adjusting an orientation of said crystal.
Claim 25
Dependent Claim
22 words
The nonlinear optical crystal housing of claim 22, wherein a temperature of said holder is adjusted and controlled by a temperature controller.
Claim 26
Dependent Claim
18 words
The nonlinear optical crystal housing of claim 21, wherein moisture is removed from said housing by said port.
Claim 27
Dependent Claim
24 words
The nonlinear optical crystal housing of claim 21, wherein moisture is removed by said fluid access port and thereby prevented from accessing said crystal.
Claim 28
Dependent Claim
26 words
The nonlinear optical crystal housing of claim 21, wherein dry air is circulated by said at least one port for preventing moisture from accessing said crystal.
Claim 29
Dependent Claim
21 words
The nonlinear optical crystal housing of claim 21, wherein the temperature is controlled to within 0.1° C. by a temperature controller.
Claim 30
Dependent Claim
21 words
The nonlinear optical crystal housing of claim 27, wherein the temperature is maintained at approximately 100° C. by said temperature controller.
Claim 31
Dependent Claim
49 words
An assembly for improving the performance of a non-linear optical element, comprising: a sealed chamber for holding the non-linear optical element; a pair of opposed windows formed in the chamber; a heater for raising the temperature of the non-linear optical element; and means for removing contaminants from the chamber.
Claim 32
Dependent Claim
49 words
An assembly for improving the performance of a non-linear optical element, comprising: a sealed chamber for holding the non-linear optical element; a pair of opposed windows formed in the chamber; a heater for raising the temperature of the non-linear optical element; and means for removing contaminants from the chamber.
Claim 33
Dependent Claim
20 words
An assembly as recited in claim 29 wherein said means for removing contaminants includes a means for evacuating the chamber.
Claim 34
Dependent Claim
30 words
An assembly as recited in claim 29 wherein said means for removing contaminants includes a circulation system for purging the chamber with one of an inert gas and dry air.
Claim 35
Independent Claim
50 words
A method of operating a laser system which generates a laser beam and includes a non-linear optical element comprising: mounting the non-linear optical element in a sealed chamber having input and output windows for transmitting the laser beam; heating the non-linear optical element; and removing contaminants from the sealed chamber.
Claim 36
Independent Claim
50 words
A method of operating a laser system which generates a laser beam and includes a non-linear optical element comprising: mounting the non-linear optical element in a sealed chamber having input and output windows for transmitting the laser beam; heating the non-linear optical element; and removing contaminants from the sealed chamber.
Claim 37
Dependent Claim
24 words
A method as recited in claim 32 wherein said step of removing contaminants includes evacuating gas from the chamber by applying a vacuum thereto.
Claim 38
Dependent Claim
27 words
A method of as recited in claim 32 wherein said step of removing contaminants includes recirculating one of an inert gas and dry air within the chamber.
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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) | 2002-12-13 | 2003-06-14 | 2003-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-12-13 | 2007-06-14 | 2007-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-12-13 | 2011-06-14 | 2011-12-14 | $7700.00 | Window Closed / Lapsed |