Abstract: A gas laser includes a plurality of electrically conductive electrodes contained within a hollow housing that contains a laser gas medium. The electrodes surround and define a laser bore in which a plasma is excited by the electrodes. Each of the electrodes defining the laser bore has an ungrounded electrical potential that provides improved laser gain at a lower gas temperature. Each of the electrodes may be driven with a controlled, varying electrical potential, such as a radio frequency electrical potential.

Abstract: A laser includes a split-wave hybrid resonator that produces a high quality laser beam from a low gain laser medium. The split-wave hybrid resonator includes a resonator cavity formed by a pair of resonator mirror surfaces positioned at opposite ends of the laser medium and a pair of resonator walls positioned on opposite sides of the resonator cavity. The resonator walls are separated from each other by a separation distance such that the resonator cavity has a Fresnel number between approximately 0.5 and 1.5. At least one of the resonator walls includes a first ring oscillation filter adjacent to the lasing medium to filter out ring oscillations within the laser medium. One or more of the resonator walls may include first and second wall portions angled with respect to each other to form a wave-front splitting interferometer. The resonator mirrors are tilted off-axis with respect to the resonator walls.

Abstract: A diffusion-cooled laser has a lasing region shaped to provide a high power output laser beam of a high optical quality. The lasing region, which contains a lasing medium, has a narrow-aperture section and a free-space section. The narrow-aperture section is defined by resonator walls spaced apart a sufficiently small distance that enables effective excitation and cooling of the lasing medium. The free-space section is defined by resonator walls spaced apart a sufficiently larger distance that enables the laser beam to expand without restriction from the resonator walls in the free-space section. The narrow-aperture section enables the laser to generate a high power laser beam using a relatively low (40 MHz) ISM frequency. The free-space section allows the laser beam to expand sufficiently to exit the lasing region with a shape that is easily focused by inexpensive optical elements.

Abstract: An optical waveguide and method for guiding a laser beam through a channel member having a fluid medium disposed therein. A refractive index gradient is created in the fluid medium which causes the fluid medium to guide the laser beam through the channel member. The refractive index gradient results when a temperature index gradient is created in the fluid medium by heating the channel member wall. The channel member can be externally heated using a separate heating source or the channel member can be heated from the inside by the laser beam itself. A fluid pump is used to create a fluid flow in the fluid medium in order to maintain the temperature and refractive index gradients in the fluid medium.

Abstract: A laser scanner having first and second scanning mirrors and a correction circuit that removes distortions caused by interaction between the scanning mirrors. Preferably, the first scanner mirror is an off-axis mirror that is positioned to produce a single, substantially invariant pupil on the second scanning mirror. Preferably the scanner uses a reflective beam expander to magnify an input laser beam received from a laser source. Preferably, the reflective beam expander is implemented using two spherical mirrors positioned to form the input laser beam into a Z-folded beam path. The folded beam path increases the distance between the laser source and the focusing lens, which results in a clear focused spot and does so using spherical mirrors which are much less expensive than the infrared lenses used in the prior art. The reflective beam expander is also wavelength insensitive.

Abstract: A compact drive system drives an RF-excited gas laser to produce laser energy. The drive system is implemented on a ceramic circuit board having a high dielectric constant. The drive system includes an RF energy source that produces RF energy that is transmitted by a quarter-wave transmission line to the plasma tube of the laser. The transmission line is a microstrip transmission line having a conductive strip and a conductive ground plane bonded to opposite sides of the ceramic circuit board. Such a microstrip transmission line enables the entire drive system to be implemented on the ceramic circuit board. The drive system includes a feedback path to the input of the RF energy source transistor, which enables the drive system to be self-oscillating in that the frequency of the RF energy produced is maintained equal to the resonant frequency of the laser.

Abstract: An electrically self-oscillating radio frequency-excited gas laser. The discharge section of the laser resonates at a desired radio frequency as a result of incorporating the discharge section into the feedback loop of a power oscillator circuit. This laser structure facilitates initial plasma breakdown and adapts its frequency depending upon whether the gas in the discharge section has broken down. When the laser plasma tube is integrated with the oscillator, the laser is also somewhat smaller compared to gas lasers having conventional crystal-controlled amplifier chains.

Abstract: All-metal, RF-excited gas lasers employing organic or inorganic insulating material including polyimide and aluminum oxide to provide a structurally homogeneous laser capable of low-cost fabrication and broad temperature ranges suitable for military and commercial applications. A particularly novel embodiment employs an extruded housing and electrodes and relies almost solely upon gas conduction and gas convection cooling, obviating compression heat sinking. The latter embodiment can permit gas flow between the laser cavity and tube gas chambers through elongated gaps or spaces at the corners of the cavity. Insulators support the electrodes in a few places and facilitate simple, low-cost assembly. The latter geometry is also well adapted for use in folded configurations featuring multiple lasing sections and a common discharge electrode.