title: Multiple harmonic generators for improved efficiency of laser-pumped lasers.
abstract: A multistage system of three second-harmonic-generating crystals has been used to improve the total conversion efficiency from the fundamental at 1.06 mum to the second harmonic at 532 nm. Demagnifying telescopes placed into the path of the residual fundamental light, after chromatic separation of the second harmonic, allow further second-harmonic crystals to be used. More than 97% conversion has been obtained from 207-mJ, Q -switched Nd:YAG laser pulses at 1.06 mum, producing more than 201 mJ at 532 nm. Good agreement is achieved between experiment and theory for the spatial and temporal evolution of the second-harmonic beams at each stage.
authors.forename: G
authors.initials: G
authors.lastname: Cook