The present invention contemplates a simplified laser oscillator-amplifier system
for deep UV generation. The simplified system employs same type of gain media in
both the oscillator and the amplifier and utilizes a single pump pulse split to
pump both the oscillator and the amplifier. A short cavity oscillator is operated
near lasing threshold to produce a seed pulse with a narrow spectral bandwidth
and long pulse duration. A short cavity amplifier is Q-switched to amplify the
seed pulse to produce a single short pulse with good energy extraction efficiency.
The amplifier is simply a short cavity, Q-switched laser. Short pulse is obtained
with short cavity length and high gain of the amplifier. Consequently, the simplified
laser oscillator-amplifier system can accommodate a long pump pulse to produce
a nanosecond pulse suitable for deep UV laser generation.