This reference book concentrates on microstructuring surfaces of optical materials with directed fluxes of off-electrode plasma generated by high-voltage gas discharge and developing methods and equipment related to this technique. It covers theoretical and experimental studies on the electrical and physical properties of high-voltage gas discharges used to generate plasma outside an electrode gap. A new class of methods and devices that makes it possible to implement a series of processes for fabricating diffraction microstructures on large format wafers is also discussed.