The object of a pulsed laser arrangement and a method for adjusting the
pulse length of laser pulses is to change the pulse length over a wide
range substantially independent from the laser output power, in
particular to counteract a reduction in output and to prevent a negative
change in the beam parameters when lengthening the pulse by means of
varying the oscillator output. A multistage laser amplifier in which an
amplifying medium with a small-signal amplification of more than 10 is
provided in every stage (17-22) is arranged downstream of a diode-pumped
Q-switched solid state laser oscillator with variable oscillator output
for supplying oscillator pulses. The total small-signal amplification
brought about by all of the amplifying media is greater than 1000. The
pulsed laser arrangement and the method can be used for industrial and
medical purposes requiring pulse lengths in the range of several hundred
ns to several .mu.s at pulse repetition rates between 10 kHz and 200 khz.