A speckle
pattern is a random intensity pattern produced by the mutual interference of a set of wavefronts. To reduce the
speckel effecte the laser muss have the follows caracteristics : Broad spectral
width No polarised
output Superradiant
emission Vibration of the
laser medium All this 4
conditions will be satisfied with a microsecond wall ablation flashlamp pumped
Dye laser. The Rhodamine 590
dye has a spectral bandwidth of 80 nm the superradiant amplification was
achieved by using a long and small diameter quartz tube containing the laser
dye in methanol. No resonator was
used only a rear mirror and a flat antireflexion output coupler . The vibration of
the laser medium is favorized by the very high shock waves during the ablation Of the flash wall
in 1 microsecond. The laser emission is 500 nanoseconds and 300 mJ ( 600kW) | 
