Single Nanosecond Pulse Generation at 10.6 μ Using a Brewster Angle Modulator

A method is described for generating single millijoule pulses of nanosecond duration through use of a CO2 laser mode-locked with a Brewster angle, acousto-optic modulator coupled with an electro-optic switch (extinction ratio of 50 000:1) driven by a laser-triggered spark gap. The Brewster angle geometry eliminates the damage problems associated with the use of AR-coated normal incidence modulators.