Abstract

A new concept for generating high beam quality from high pulse energy optical parametric oscillators has been developed and experimentally demonstrated. The idea is to use two different types of crystals type 2 phase matched for the same interaction, but with orthogonal walk-off directions, in the same resonator. By adding BBO crystals to a KTA-based OPO, the astigmatism was removed from the beam and beam quality was improved from M² ~ 2 × 9 to M² ~ 2 × 2 without decreasing the conversion efficiency.

© 2010 Optical Society of America