6 mJ@3.3kHz Q-switched single mode single-frequency Nd:YAG end pumped laser

End pumped MOPA Nd:YAG pulsed laser was built and investigated. High extraction efficiency ∼50% in single-pass amplifier is achieved due to high small-signal gain provided with longitudinal pumping. Pumping of amplifier is near uniformly distributed along 2 laser rods with low concentration using two-lens relay between them in order to decrease end overheating.