Abstract: A lasing method including the steps of providing a laser resonator; utilizing birefringence compensation in said resonator whereby said resonator is induced to operate in a Laguerre-Gaussian higher order mode; and utilizing polarized outcoupling of lasing energy at said higher order mode from said resonator. In the illustrative application, the laser resonator is a high-power, solid-state laser resonator. In the specific embodiment, the inventive method further includes the step of changing an outcoupling preference for a non-degenerate high-order Laguerre-Gaussian mode. In one embodiment, the step of changing outcoupling preference includes the step of changing an outcoupling polarization. In another embodiment, the step of changing outcoupling preference includes the step of changing an orientation of a roof edge of a prism in the laser resonator.

Abstract: A lasing method including the steps of providing a laser resonator; utilizing birefringence compensation in said resonator whereby said resonator is induced to operate in a Laguerre-Gaussian higher order mode; and utilizing polarized outcoupling of lasing energy at said higher order mode from said resonator. In the illustrative application, the laser resonator is a high-power, solid-state laser resonator. In the specific embodiment, the inventive method further includes the step of changing an outcoupling preference for a non-degenerate high-order Laguerre-Gaussian mode. In one embodiment, the step of changing outcoupling preference includes the step of changing an outcoupling polarization. In another embodiment, the step of changing outcoupling preference includes the step of changing an orientation of a roof edge of a prism in the laser resonator.

Abstract: A solid state pump cavity comprising a laser rod encased by diffusion bonding inside an outer cladding. The outer cladding provides the ability to efficiently conduct heat away from the laser rod. The outer cladding is also configured to absorb spontaneous laser radiation that would otherwise be re-amplified by the laser rod. Diffusion bonding of the outer cladding to the laser rod forms a seamless optical boundary between the outer cladding and the laser rod. An alternative embodiment of the pump cavity comprises multiple segments of laser rod and outer cladding assemblies coupled together with undoped sections that are diffusion bonded to the ends of the laser rod and outer cladding assemblies.

Abstract: A solid-state laser beam amplifier with integrated reflective surface. A rectangular slab gain medium receives a first portion of an input laser beam along a first zigzag reflection path within the slab. The gain medium also receives a second portion of the input laser beam that has been reflected from an integral reflective surface such that the two portions traverse the gain medium along complementary zigzag paths. The zigzag paths are defined by total internal reflection of the beam portions as they propagate through the gain medium slab. A similar reflective surface may be positioned relative to the exit end of the gain medium slab, which redirects all of the output beam portions in a parallel direction. The gain medium may be Ytterbium or neodymium doped yttrium aluminum garnet. The gain medium may be formed as a high aspect ratio rectangular slab and may be clad with sapphire.

Abstract: A solid-state laser beam amplifier with integrated reflective surface. A rectangular slab gain medium receives a first portion of an input laser beam along a first zigzag reflection path within the slab. The gain medium also receives a second portion of the input laser beam that has been reflected from an integral reflective surface such that the two portions traverse the gain medium along complementary zigzag paths. The zigzag paths are defined by total internal reflection of the beam portions as they propagate through the gain medium slab. A similar reflective surface may be positioned relative to the exit end of the gain medium slab, which redirects all of the output beam portions in a parallel direction. The gain medium may be Ytterbium or neodymium doped yttrium aluminum garnet. The gain medium may be formed as a high aspect ratio rectangular slab and may be clad with sapphire.

Abstract: A solid state pump cavity comprising a laser rod encased by diffusion bonding inside an outer cladding. The outer cladding provides the ability to efficiently conduct heat away from the laser rod. The outer cladding is also configured to absorb spontaneous laser radiation that would otherwise be re-amplified by the laser rod. Diffusion bonding of the outer cladding to the laser rod forms a seamless optical boundary between the outer cladding and the laser rod. An alternative embodiment of the pump cavity comprises multiple segments of laser rod and outer cladding assemblies coupled together with undoped sections that are diffusion bonded to the ends of the laser rod and outer cladding assemblies.

Abstract: An optical parametric oscillator comprising two meniscus mirrors disposed on opposite sides of a nonlinear medium that forms a confocal unstable resonator. A reduced-to-practice embodiment uses concave-convex mirrors in a confocal arrangement disposed on opposite sides of a KTP crystal used as the nonlinear medium. The optical parametric oscillator and confocal unstable resonator of the present invention exhibits improved beam divergence angles.

Abstract: A laser pump cavity assembly having a laser rod with a ground outer surface positioned concentrically within an annular jet sleeve which is, in turn, positioned concentrically within an annular outer sleeve. The outer sleeve is coated with a dielectric coating having slits therein arranged to receive focused optical pump radiation from respective laser diode arrays, the pump radiation being transmitted through the outer sleeve and jet sleeve to excite the laser rod. The jet sleeve is positioned to define cooling fluid chambers between the outer sleeve and the jet sleeve, and between the jet sleeve and the laser rod, and is provided with a series of jet holes for directing cooling fluid to impinge perpendicularly on the laser rod. The end faces of the jet sleeve and outer sleeve are further coated with dielectric material to enhance the efficiency of the device. The cooperating end caps which mount the outer sleeve, jet sleeve, and laser rod employ a number of advantageous self-aligning and sealing features.

Abstract: A technique for passively removing heat from an optical element in a laser system through its optically transmissive faces. Heat is removed by way of optically transmissive heat sinks or other heat conducting media disposed adjacent the optically transmissive surfaces of the optical element. Heat is transferred out of the optical element in a direction parallel to the direction of propagation of energy, thus minimizing problems associated with thermal gradients. Devices employing optical elements such as nonlinear frequency conversion crystals and laser crystals may utilize the heat management approach of the present invention to achieve better performance. Heat is transferred to the heat conducting media by direct contact, or through narrow gas-filled gaps disposed between the optical element and the heat conducting media.

Abstract: A knife blade clamp for a Carthage-Norman type of log chipper and having a substantially right triangular cross-sectional contour having an upper face, back face and hypotenuse surface, is provided with a series of slots on its back face. The slots communicate between an elongated depression on the back face and the hypotenune surface. By virtue of the series of slots, there is less accumulation of fine dust adjacent the back face which would thwart the removability of the associated knife for servicing.

Abstract: Lenses (30', 32') are orthogonally tilted with respect to one another in a telescope to provide imaging for an amplifier-phase conjugate mirror (PCM)(10) in a laser oscillator/amplifier (12). This mutually orthogonal tilting avoids the problem of air breakdown which occurs when the laser energy is otherwise focused at a single point and thus avoids the need to use a vacuum cell to suppress the sparking at the telescope's focus. An adjustment of the tilting of one lens (32') with respect to the other lens (30') also avoids astigmatism.