Sven E Nelte

6389043, May 14, 2002

Mar 7, 2000

09/520695

Sven E. Nelte - Carlsbad CA
David E. Hargis - San Diego CA

Melles Griot, Inc. - Carlsbad CA

H01S 310

372 22, 372 92, 372 98

An efficient frequency-converted solid state laser that outputs a single beam utilizing an angled reflector situated within the laser cavity. The laser comprises an optical cavity including a first reflector and a second reflector. A gain medium situated within the optical cavity is energized by a pump source to excite a laser emission at a fundamental wavelength. A nonlinear material is arranged within the optical cavity to convert the laser emission to a second wavelength. The angled reflector, which is reflective of the second wavelength and transmissive of the first wavelength, is situated within the optical cavity between the first reflector and the nonlinear material. In operation, the forward-propagating converted beam is reflected from the second reflector, and then combines with the reverse-propagating converted beam. The angled reflector reflects the combined beam so that it exits from the optical cavity at a nonzero exit angle. Typically, the angled reflector and the exit angle are selected so that the angled reflector reflects substantially all polarizations of the combined beam.

57967660, Aug 18, 1998

Jan 17, 1997

8/784051

David E. Hargis - La Jolla CA
Sven E. Nelte - Carlsbad CA

Laser Power Corporation - San Diego CA

H01S 304

372 36

A longitudinally-cooled laser element assembly comprises an optically transparent heat sink (OTH) coupled to a laser element and a heat sink. An etalon structure including a first flat surface and a second, substantially parallel flat surface is formed in the laser element and/or the OTH. In some embodiments, a balanced etalon is provided by forming a reflector on the second flat surface of the etalon that has a reflectivity approximately equal to the Fresnel loss at the interface between the OTH and the laser element. In some embodiments the laser element assembly includes a second OTH coupled to the laser element at a second interface, thereby defining a second Fresnel loss. Preferably, the second OTH has an index of refraction substantially equal to the index of refraction of the first OTH, so that said first and second Fresnel losses are approximately equal and a balanced etalon is formed. In some embodiments the laser element comprises a solid-state gain medium. In other embodiments the laser element comprises a nonlinear frequency conversion crystal.

61012017, Aug 8, 2000

Aug 6, 1998

9/130378

David E. Hargis - San Diego CA
Sven E. Nelte - Carlsbad CA

Melles Griot, Inc. - Carlsbad CA

H01S 304

372 36

An optically-pumped laser comprises a laser cavity, a solid-state gain medium and an optically transparent heat sink (OTH) situated within the laser cavity. The gain medium and OTH are thermally coupled and at least one of the solid-state gain medium and the OTH has an etalon structure thereby improving laser efficiency. The OTH advantageously provides effective heat transfer and permits higher average power operation, particularly for thin solid-state laser materials. A metallic heat sink may be thermally coupled to the OTH to improve heat transfer. In some embodiments, the laser is end-pumped with optical pump radiation through the OTH. A second intracavity OTH may be thermally coupled to the gain medium opposite the first OTH to provide longitudinal heat transfer in both directions. A frequency-converted laser may be provided by using a nonlinear material longitudinally cooled on each end by intracavity OTHs, at least one of which comprises an etalon structure. In some frequency-converted laser embodiments, first and second converted beams are output from the laser cavity along separate optical paths in a manner that advantageously prevents intracavity interference between the two converted beams.

55747400, Nov 12, 1996

Aug 23, 1994

8/295006

David E. Hargis - La Jolla CA
Sven E. Nelte - Carlsbad CA

Laser Power Corporation - San Diego CA

H01S 316

372 41

A monolithic diode pumped solid-state laser (11) comprising as the laser host neodymium-doped yttrium orthovanadate (Nd:YVO. sub. 4) (12, 52) or neodymium-doped gadolinium orthovanadate (Nd:GdVO. sub. 4) (57, 67) operating on the. sup. 4 F. sub. 3/2. fwdarw. sup. 4 I. sub. 9/2 (. about. 914 nm or. about. 912 nm respectively) transition, to which a suitable nonlinear optic material (16), such as potassium niobate (KNbO. sub. 3) or beta barium borate (BBO), is bonded. The nonlinear crystal gives rise to intracavity frequency doubling to. about. 457 or. about. 456 nm. The microlaser is a composite cavity formed from a gain medium crystal and a nonlinear frequency doubling material which together have four spaced parallel dielectrically coated faces (14, 17, 18, 15) and which is positioned in close proximity to a diode laser pump source (13) for phase-matched harmonic generation of blue light along an axis of propagation which lies substantially perpendicular to the two faces of the composite cavity. By employing specific doping concentration-lengths products of lasant material and pumping the gain medium which has a specific crystalline orientation the desired efficient blue microlaser is achieved. Alternative embodiments combine the Nd:YVO. sub.

57612277, Jun 2, 1998

Dec 5, 1996

8/760702

David E. Hargis - La Jolla CA
Sven E. Nelte - Carlsbad CA

Laser Power Corporation - San Diego CA

H01S 310

372 22

An intracavity frequency-converted laser having an intracavity reflector situated to reflect converted radiation at a nonzero angle with respect to the optical axis. The laser includes an optical cavity that defines an optical axis, a gain medium for providing a fundamental laser emission, a pump source for pumping the gain medium, and a nonlinear material for frequency converting the fundamental laser emission to provide first and second converted beams that propagate in opposite directions within the optical cavity. An angled reflector that reflects optical radiation at the converted wavelength, but is transmissive at the fundamental wavelength is situated within the optical cavity to reflect one of the converted beams along a path angled with respect to the optical axis. Advantageously, reflecting the converted radiation before it propagates through the gain medium avoids absorption losses. Furthermore, interference between the reflected beam and other converted beam is avoided due to the angle of reflection.

57517517, May 12, 1998

Oct 21, 1996

8/731823

David E. Hargis - La Jolla CA
Sven E. Nelte - Carlsbad CA

Laser Power Corporation - San Diego CA

H01S 316

372 41

A monolithic diode pumped solid-state laser (11) comprising as the laser host neodymium-doped yttrium orthovanadate (Nd:YVO. sub. 4) (12, 52) or neodymium-doped gadolinium orthovanadate (Nd:GdVO. sub. 4) (57, 67) operating on the. sup. 4 F. sub. 3/2. fwdarw. sup. 4 I. sub. 9/2 (. about. 914 nm or. about. 912 nm respectively) transition, to which a suitable nonlinear optic material (16), such as potassium niobate (KNbO. sub. 3) or beta barium borate (BBO), is bonded. The nonlinear crystal gives rise to intracavity frequency doubling to. about. 457 or. about. 456 nm. The microlaser is a composite cavity formed from a gain medium crystal and a nonlinear frequency doubling material which together have four spaced parallel dielectrically coated faces (14, 17, 18, 15) and which is positioned in close proximity to a diode laser pump source (13) for phase-matched harmonic generation of blue light along an axis of propagation which lies substantially perpendicular to the two faces of the composite cavity. By employing specific doping concentration-lengths products of lasant material and pumping the gain medium which has a specific crystalline orientation the desired efficient blue microlaser is achieved. Alternative embodiments combine the Nd:YVO. sub.