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US4408329A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser device with intraresonator harmonic generator

Assignee: United States Department of the Navy
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Filing: 1978-12-04
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Granted: 1983-10-04
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Expires: 1998-12-04
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Abstract

Abstract A laser device for generating frequency-doubled laser pulses at maximum eciency. A laser rod is optically pumped to radiate unpolarized light at 1.064μ wavelength for transmission within a ring-type resonator defined by a flat mirror and a turning prism. The light from one end of the rod is linearly polarized by a beam splitter into two parallel beams of orthogonal components which are transmitted through an 0.532μ output mirror, a frequency doubler phase matched for one component, and a Q-switch, to the turning prism for return along the beam of the other component to the beamsplitter. The output mirror, doubler and Q-switch are substantially ineffective during the pumping cycle, and because the component beam axes are reversed, the light does not return to the rod for stimulating light emission. After peak level pumping, however, the Q-switch is biased to rotate each component one quarter wavelength and return the components to combine and reenter the rod for stimulated light emission. The frequency doubler, now receiving high power radiation, transforms a portion of the returning 1.064μ component to a 0.532μ component which is then reflected out of the resonator by the output mirror.

Inventors

  • 👤 Gerald D. Ferguson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:42
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/108; H01S3/109; H01S3/13; H01S3/131; H01S3/05; H01S3/08; H01S3/08054; H01S3/08059; H01S3/081; H01S3/0813; H01S3/11; H01S3/1123; H01S3/115

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 257 words
A laser system, comprising, in combination: a laser means for radiating light of a first wavelength in opposite directions along a first path when energized; first reflection means positioned on said first path for reflecting the light from one direction into the laser means; beamsplitter means positioned within the first path for polarizing the light from the other direction into a first component of radiation along the first path and into a second component along a second path parallel to said first path; second reflection means positioned within said first and second paths for reflecting light in the first path into the second path and light in the second path into said first path; Q-switch means positioned within said first and second paths for selectively rotating the polarized components one fourth of said first wavelength when energized; frequency multiplying means positioned within said first and second paths between said beamsplitter means and said Q-switch means for mulitplying the frequency of light of said first wavelength and second component to produce light along said first and second paths of a second wavelength and of the second component; third reflection means highly reflective to said first wavelength and highly transmissive to said second wavelength angularly positioned to first and second paths and between said beamsplitter and said frequency multiplier means for reflecting the light of said second wavelength in one direction along parallel third and fourth paths angularly displaced from said first and second paths; and synchronizing means connected for sequentially energizing said laser means and said Q-switch means.
Claim 2
Dependent Claim 257 words
A laser system, comprising, in combination: a laser means for radiating light of a first wavelength in opposite directions along a first path when energized; first reflection means positioned on said first path for reflecting the light from one direction into the laser means; beamsplitter means positioned within the first path for polarizing the light from the other direction into a first component of radiation along the first path and into a second component along a second path parallel to said first path; second reflection means positioned within said first and second paths for reflecting light in the first path into the second path and light in the second path into said first path; Q-switch means positioned within said first and second paths for selectively rotating the polarized components one fourth of said first wavelength when energized; frequency multiplying means positioned within said first and second paths between said beamsplitter means and said Q-switch means for mulitplying the frequency of light of said first wavelength and second component to produce light along said first and second paths of a second wavelength and of the second component; third reflection means highly reflective to said first wavelength and highly transmissive to said second wavelength angularly positioned to first and second paths and between said beamsplitter and said frequency multiplier means for reflecting the light of said second wavelength in one direction along parallel third and fourth paths angularly displaced from said first and second paths; and synchronizing means connected for sequentially energizing said laser means and said Q-switch means.
Claim 3
Dependent Claim 24 words
A laser system according to claim 1 wherein said beamsplitter means polarizes and separates said first and second radiated components orthogonal to each other.
Claim 4
Dependent Claim 21 words
A laser system according to claim 2 wherein said frequency multiplying means doubles the frequency of light of said first wavelength.
Claim 5
Dependent Claim 17 words
A laser system according to claim 3 wherein said first reflection means is a flat, fully-reflecting mirror.
Claim 6
Dependent Claim 47 words
A laser system according to claim 4 wherein said second reflection means is a Poro prism with its hypotenuse face normal to said first and second paths for receiving the light and each of the shorter faces reflecting the light from one path into the other path.
Claim 7
Dependent Claim 15 words
A laser system according to claim 5 wherein said beamsplitter means is a birefringent crystal.
Claim 8
Dependent Claim 24 words
A laser system according to claim 7 wherein said third reflection means is angularly positioned at approximately 45° to said first and second paths.
Claim 9
Dependent Claim 19 words
A laser system according to claim 1 wherein said laser means includes a medium of a solid state material.
Claim 10
Dependent Claim 15 words
A laser system according to claim 8 wherein said material is neodymium-doped yttrium aluminum garnet.
Claim 11
Dependent Claim 17 words
A laser system according to claim 9 wherein said frequency multiplying means is a second harmonic generator.
Claim 12
Dependent Claim 17 words
A laser system according to claim 10 wherein said first reflection means is a flat, fully-reflecting mirror.
Claim 13
Dependent Claim 47 words
A laser system according to claim 11 wherein said second reflection means is a Poro prism with its hypotenuse face normal to said first and second paths for receiving the light and each of the shorter faces reflecting the light from each path into the other path.
Claim 14
Dependent Claim 15 words
A laser system according to claim 12 wherein said Q-switch means is a Pockel's cell.
Claim 15
Dependent Claim 15 words
A laser system according to claim 13 wherein said beamsplitter means is a birefringent crystal.

References Cited (Backward Citations)

US3464026A Cited
US3508166A Cited
US3564454A Cited
US3740663A Cited
US3831106A Cited
US3975693A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-10-03 1987-04-04 1987-10-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-10-03 1991-04-04 1991-10-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-10-03 1995-04-04 1995-10-04 $7700.00 Window Closed / Lapsed

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