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Laser-Induced Damage in Optical Materials
irradiance and reduction of laser spot size toward single laser wavelength (Gruzdev and
Libenson 1994, 2000). at depolarization might be responsible for the specic polariza-
tion dependence of LID threshold reported for small laser spots (Soileau etal. 1989) since
it tends to produce similar polarization patterns for both initial linear and initial circular
polarizations at self-focus area. erefore, reduction of the ratio of LID thresholds for
the two dierent polarizations with decrease of laser spot radius down to few microm-
eters does not mean suppression of self-focusing but might result from ...