Abstract: To enable several orders of magnitude increases in average power and energy handling capability of Faraday rotators, the technology utilizes high speed gas cooling to efficiently remove thermal loading from the Faraday optic faces while minimizing the thermal wavefront and thermal birefringence by creating a longitudinal thermal gradient. A recirculating gas cooling manifold accelerates the gas over the surface of the slab to create a turbulent flow condition which maximizes the surface cooling rate. The technology further provides a spatially uniform thermal profile on the Faraday slabs.

Abstract: Reduction or elimination of negative consequences of reflected stray light from lens surfaces is achieved by propagating a laser beam through an eccentric pupil that excludes the optical axis of the system, which is rotationally symmetric. In such systems, stray light reflections eventually are focused onto the unique optical axis of the system, in either a real or virtual focal region. By using an eccentric pupil, all damage due to focusing of the stray light lies outside of the beam. These focal regions can, e.g., be physically blocked to eliminate beam paths that lead to optical damage, re-pulse beams and parasitic lasing.

Abstract: An architecture for an inertial confinement fusion system is disclosed. The system includes a fusion chamber for producing neutrons from a fusion reaction, and a laser system in which lasers are arranged about a vacuum chamber to provide energy to the fusion chamber to initiate the fusion reaction. The beam paths between the lasers and the fusion chamber are configured to prevent neutrons from the fusion chamber from reaching the laser system at a level that would preclude human access to the laser system.

Abstract: Techniques are provided for scaling the average power of high-energy solid-state lasers to high values of average output power while maintaining high efficiency. An exemplary technique combines a gas-cooled-slab amplifier architecture with a pattern of amplifier pumping and extraction in which pumping is continuous and in which only a small fraction of the energy stored in the amplifier is extracted on any one pulse. Efficient operation is achieved by propagating many pulses through the amplifier during each period equal to the fluorescence decay time of the gain medium, so that the preponderance of the energy cycled through the upper laser level decays through extraction by the amplified pulses rather than through fluorescence decay.

Abstract: To enable several orders of magnitude increases in average power and energy handling capability of Faraday rotators, the technology utilizes high speed gas cooling to efficiently remove thermal loading from the Faraday optic faces while minimizing the thermal wavefront and thermal birefringence by creating a longitudinal thermal gradient. A recirculating gas cooling manifold accelerates the gas over the surface of the slab to create a turbulent flow condition which maximizes the surface cooling rate. The technology further provides a spatially uniform thermal profile on the Faraday slabs.

Abstract: Techniques are provided for scaling the average power of high-energy solid-state lasers to high values of average output power while maintaining high efficiency. An exemplary technique combines a gas-cooled-slab amplifier architecture with a pattern of amplifier pumping and extraction in which pumping is continuous and in which only a small fraction of the energy stored in the amplifier is extracted on any one pulse. Efficient operation is achieved by propagating many pulses through the amplifier during each period equal to the fluorescence decay time of the gain medium, so that the preponderance of the energy cycled through the upper laser level decays through extraction by the amplified pulses rather than through fluorescence decay.

Abstract: A laser amplifier system includes a gain medium having a longitudinal axis and a plurality of sides substantially parallel to the longitudinal axis. The laser amplifier system also includes a waveguide having a plurality of inner surfaces. Each of the inner surfaces is optically coupled to one of the plurality of sides of the gain medium. The waveguide also includes a plurality of outer surfaces. The laser amplifier system further includes a cladding optically coupled to the outer surfaces of the waveguide.

Abstract: An architecture for a fusion power plant is disclosed. The plant includes a fusion chamber for producing neutrons from a fusion reaction, and a laser system in which lasers are arranged about a vacuum chamber to provide energy to the fusion chamber to initiate the fusion reaction. The beam paths between the lasers and the fusion chamber are configured to prevent neutrons from the fusion chamber from reaching the laser system at a level that would preclude human access to the laser system.

Abstract: A main amplifier system includes a first reflector operable to receive input light through a first aperture and direct the input light along an optical path. The input light is characterized by a first polarization. The main amplifier system also includes a first polarizer operable to reflect light characterized by the first polarization state. The main amplifier system further includes a first and second set of amplifier modules. Each of the first and second set of amplifier modules includes an entrance window, a quarter wave plate, a plurality of amplifier slablets arrayed substantially parallel to each other, and an exit window. The main amplifier system additionally includes a set of mirrors operable to reflect light exiting the first set of amplifier modules to enter the second set of amplifier modules and a second polarizer operable to reflect light characterized by a second polarization state.

Abstract: A spatial filter includes a first filter element and a second filter element overlapping with the first filter element. The first filter element includes a first pair of cylindrical lenses separated by a first distance. Each of the first pair of cylindrical lenses has a first focal length. The first filter element also includes a first slit filter positioned between the first pair of cylindrical lenses. The second filter element includes a second pair of cylindrical lenses separated by a second distance. Each of the second pair of cylindrical lenses has a second focal length. The second filter element also includes a second slit filter positioned between the second pair of cylindrical lenses.

Abstract: A main amplifier system includes a first reflector operable to receive input light through a first aperture and direct the input light along an optical path. The input light is characterized by a first polarization. The main amplifier system also includes a first polarizer operable to reflect light characterized by the first polarization state. The main amplifier system further includes a first and second set of amplifier modules. Each of the first and second set of amplifier modules includes an entrance window, a quarter wave plate, a plurality of amplifier slablets arrayed substantially parallel to each other, and an exit window. The main amplifier system additionally includes a set of mirrors operable to reflect light exiting the first set of amplifier modules to enter the second set of amplifier modules and a second polarizer operable to reflect light characterized by a second polarization state.

Abstract: A novel method and apparatus for suppressing ASE and parasitic oscillation modes in a high average power laser is introduced. Such an invention, as disclosed herein, uses diffraction gratings to increase gain, stored energy density, and pumping efficiency of solid-state laser gain media, such as, but not limited to rods, disks and slabs. By coupling predetermined gratings to solid-state gain media, such as crystal or ceramic laser gain media, ASE and parasitic oscillation modes can be effectively suppressed.