A diffraction limited working beam at a given frequency is amplified without degrading its diffraction limited quality by diverting a minor portion of the beam as a probe beam, and amplifying the remaining portion of the working beam with a high power pump beam at a different wavelength. The amplification...http://www.google.fr/patents/US5373526?utm_source=gb-gplus-shareBrevet US5373526 - Apparatus and method for optical energy amplification using two-beam coupling
Apparatus and method for optical energy amplification using two-beam coupling
