Formation of highly coherent radiation in a free-running ruby laser for pulsed holography

An optical scheme is proposed and implemented for a pulsed ruby laser with free lasing that allows us to achieve energy of up to 10 J per pulse, a 120--160-cm coherence length, a lasing wavelength stability ..delta..lambda/lambda from pulse to pulse of less than or equal to4 x 10/sup -7/, divergence of 85'' at the half energy level, a modulus of the spatial-coherence function within 90% of the diameter of the beam of less than or equal to0.5, and less than or equal to0.9 within 20% of the beam diameter. Very small-scale inhomogeneities associated with bubbles and foreign occlusions in the ruby elements were observed in the uniform energy distribution over the beam cross section with a 12-mm diameter at the 0.5 level from the peak. The radiation parameters obtained allow us to estimate the maximum volume of scences to be recorded holographically by counter propagating beams on PE-2 plates to be close to 1 m/sup 3/.