OPTICAL LIMITING IN LEAD GALLIATE GLASSES

Optical limiting of nanosecond duration laser pulses is demonstrated in lead galliate glasses. The dominant mechanism is thermally induced refractive index change with a small contribution from nonlinear absorption. Output fluences typically clamp about 5 µJ/cm2 for blue laser pulses and ~ 20 µJ/cm2 for red laser pulses, corresponding to optical densities of ~ 2.0. Effects of the addition of various traditional network formers (SiO2, GeO2, and B2O3) on the limiting are evaluated. Additionally, some material independent parameters associated with the optical limiting system are studied.