Passive Q switching of a ruby laser by molecular iodine vapor

The Q factor of a ruby laser was switched passively by bleaching molecular iodine vapor as a result of photodissociation of the molecules into neutral atoms. The full reversibility of this reaction ensured a long service life of the Q switch. This switch was compared with other known passive glass and dye switches. Under experimentally selected optimal conditions this type of Q switching produced pulses of 45–50 nsec duration and 0.7±0.1 J energy.