A system includes a master oscillator configured to generate a low-power optical beam. The system also includes a planar waveguide (PWG) amplifier configured to receive the low-power optical beam and generate a high-power optical beam having a power of at least about ten kilowatts. The PWG amplifier includes a single laser gain medium configured to generate the high-power optical beam. The single laser gain medium can reside within a single amplifier beamline of the system. The master oscillator and the PWG amplifier can be coupled to an optical bench assembly, and the optical bench assembly can include optics configured to route the low-power optical beam to the PWG amplifier and to route the high-power optical beam from the PWG amplifier. The PWG amplifier could include a cartridge that contains the single laser gain medium and a pumphead housing that retains the cartridge.

The present invention benefits from the determination that pre-selected spectral bandwidths that avoid the spectrum of an electronic transition of a metal/alloy vapor allow for welds substantially free from detritus that may discolor the weld. Accordingly, the present invention provides analytical methods, welding methods and fiber lasers configured to provide high quality metal/alloy welds.

The present invention benefits from the determination that pre-selected spectral bandwidths that avoid the spectrum of an electronic transition of a metal/alloy vapor allow for welds substantially free from detritus that may discolor the weld. Accordingly, the present invention provides analytical methods, welding methods and fiber lasers configured to provide high quality metal/alloy welds.

A laser amplifier device including an amplification element which includes a solid-state gain medium including a first main face and a second main face separated from each other by a distance which is smaller than the lateral dimensions. A heat spreader is thermally connected to, and substantially covering, the first main face. The heat spreader is optically transparent to a pump light and is in thermal contact with a heat sink. A first reflector substantially covers and faces the first main face and a second reflector substantially covers and faces the second main face; the reflectors being configured to reflect the pump light. The heat spreader and the first reflector are arranged such that the pump light passes through the heat spreader and through the first reflector and is reflected multiple times across the amplification element, between the first and second reflectors.

A light-emitting device includes an optical amplifier and gives off output light from optical amplifier by making a plurality of seed light rays, having mutually different wavelengths, incident on optical amplifier. Optical amplifier includes a medium portion containing a wavelength-converting element. Optical amplifier has wavelength-converting element thereof excited by excitation light to produce a plurality of partially coherent light rays, of which wavelengths are respectively the same as the mutually different wavelengths of plurality of seed light rays, thereby giving off, as output light, a multi-wavelength light beam. Excitation light has a shorter wavelength than any of plurality of seed light rays and is incident on the medium portion. Multi-wavelength light beam includes a plurality of light rays amplified. Plurality of light rays amplified have wavelengths, which are respectively the same as mutually different wavelengths of plurality of seed light rays.

A handheld LIBS device and method includes a laser assembly producing two pulsed single spatial mode output beams and a focusing optic which combines the two pulsed single spatial mode output beams at a focal point at a sample. The laser assembly includes a laser assembly housing with an output coupler window for the two pulsed single spatial mode output beams, a gain medium in the laser assembly housing between the output coupler window and an adjustable prism mount in the laser assembly housing holding a prism configured to establish two light paths through the gain medium, a source in the laser assembly housing providing pump energy to the gain medium, and a Q-switch positioned between the prism and the gain medium.

A handheld LIBS device and method includes a laser assembly producing two pulsed single spatial mode output beams and a focusing optic which combines the two pulsed single spatial mode output beams at a focal point at a sample. The laser assembly includes a laser assembly housing with an output coupler window for the two pulsed single spatial mode output beams, a gain medium in the laser assembly housing between the output coupler window and an adjustable prism mount in the laser assembly housing holding a prism configured to establish two light paths through the gain medium, a source in the laser assembly housing providing pump energy to the gain medium, and a Q-switch positioned between the prism and the gain medium.

A high-efficiency laser pumping device is provided, wherein a dielectric with or without a tapered aperture is used to accept, guide, and concentrate a pump light toward a laser gain material. Preferably, the dielectric is also a heat insulator between the pump-light source and the laser gain material. The pump-light source includes an array of light-emitting diodes, or an array of laser diodes, or an array of mixed light-emitting-diodes and laser diodes. Preferably, the input and output faces of the dielectric are optically coated with dielectric layers to maximize the pump brightness toward the laser gain material. A high-efficiency laser-pumping system with active cooling apparatus is further provided, wherein a plural number of the optical-guiding and thermal-insulation dielectrics are arranged to receive the pump lights from a plural number of pump-light sources, configured to concentrate all the pump light toward a laser gain material.

An actively cooled end-pumped solid-state laser gain device includes a bulk solid-state gain medium. An input-end of the gain medium receives a pump laser beam incident thereon and propagating in the direction toward an opposite output-end. The metal foil is disposed over a face of the gain medium extending between the input- and output-ends. A housing cooperates with the metal foil to form a coolant channel on the face the gain medium. The coolant channel has an inlet and an outlet configured to conduct a flow of coolant along the metal foil from the input-end towards the output-end. The metal foil is secured between the gain medium and portions of the housing running adjacent to the coolant channel. The metal foil provides a reliable thermal contact and imparts little or no stress on the bulk gain medium.

There are provided methods and system for providing high power, high brightness, visible laser source and laser beams. There are provided methods and systems of a direct conversion of poor beam quality visible laser light sources into a single high brightness beam in a resonant or ring laser cavity using a dual core or single core optical fiber and Stimulated Brillouin Scattering as the non-linear conversion mechanism in the graded index core of the fiber.