US Patent 7903698 Controlled optical filament generation and energy propagation

Systems and methods herein provide for the controlled formation of plasma filaments. For example, a system that radiates energy through a gas includes a laser that generates a laser pulse, and an optical element with which the laser propagates the laser pulse to control placement of an optical filament within a beam cross-section of the laser pulse. The optical filament may thereby generate a plasma filament, which may propagate energy. In this regard, an energy source may provide energy such that the plasma filament directs propagation of the energy for delivery to an application. The energy may be electrical energy, electromagnetic energy, optical energy, or a combination thereof. Generally, the optical element may impart at least one phase singularity within the laser pulse. Alternatively or additionally, the optical element may include at least one optical inhomogeneity.