Double-Clad Yb-Doped Fiber Laser and its External Cavity Frequency-Doubling

Abstract

A master oscillator power amplifier (MOPA) structured double-clad Yb-doped pulse fiber laser was presented, center wavelength of 1064nm, pulse width adjustable between 53ns-147ns, repetition rate adjustable between 50kHz-200kHz. Through external cavity frequency-doubling with a KTP crystal, the green light visibly of 532nm by fundamental beam of 1064nm was obtained. The highest frequency doubling efficiency was 16.2% when repetition rate of 50kHz and pulse width of 53ns. Relation of fundamental input beam and frequency-doubling output beam were studied through change the pulse parameters of fundamental beam and length of KTP crystal, the influences of fiber laser frequency doubling efficiency were analyzed.