The Spinning Reflector Technique for Ruby Laser Pulse Control

A method of obtaining high peak power pulses from a ruby laser oscillator by controlling the resonant cavity Q with a spinning reflector technique is described. Basic principles are discussed. A theory regarding the multiple pulse problem of slow Q switching is presented. Practical methods of eliminating critical alignment procedures and increasing effective switching speed are explained. Experimental data relating to the effect of the parameters of cavity output transmission, crystal temperature, pump energy, reflector separation and spinning speed upon laser power and energy are presented. Results of experiments at temperatures ranging from -20°F to 140°F are given. Application of the spinning reflector technique to optical ranging is discussed. Described is an experimental rangefinder designed and fabricated to show feasibility of the technique for military application.