Laser-triggered high-voltage plasma switching with diffractive optics

High-power lasers can be used to induce ionization of gases and thereby ena ble rapid triggering of electrical discharge devices, potentially faster th an any devices based on mechanical or solid-state switching. With diffracti ve optical elements (DOEs) the laser light can conveniently be directed to positions within the gas so that an electrical discharge between two high-v oltage electrodes is triggered reliably and rapidly. Here we report on two different types of DOE used for creating an electrical discharge in pure ar gon for potential high-voltage applications. One is the diffractive equival ent of a conventional axicon that yields an extended, and continuous, high- intensity focal region between the electrodes. The other is a multiple-foca l-distance kinoform-a DOE that is designed to produce a linear array of 20 discrete foci, with high peak, intensities, between the electrodes. We show that DOEs enable efficient, rapid switching and may provide increased flex ibility in the design of novel electrode configurations. (C) 2001 Optical S ociety of America.