Single-frequency ruby laser with a spatially homogeneous radiation field and variable duration of nanosecond pulses

An investigation was made of a new single-frequency ruby laser producing nanosecond pulses of variable duration. The radiation was extracted from a closed resonator with an electrooptic switch. The short radiation pulses were produced by subjecting a Pockels switch to rectangular voltage pulses of amplitude equal twice the turn-on voltage. The duration and shape of the laser radiation pulses were governed by the steepness of the leading edge of the voltage pulses. A spatially homogeneous output radiation, equivalent to the radiation of a single-mode laser, was obtained by diffraction in a system of apertures in screens placed outside the resonator. The time and space characteristics of the laser radiation were investigated. An output power of up to 10 MW was obtained in the form of short nanosecond (1.4–7 nsec) pulses in a beam of divergence close to the diffraction limit.