Study of high brightness fiber coupled diode lasers

High power fiber laser requires high brightness and power fiber coupled laser diode module as pumping source. A multi-single emitter diode with high brightness and power was developed by precision assembling and beam combining technology. 14 laser diodes beam were coupled into a core diameter of 105 m, numerical aperture (NA) 0.22 fiber via spatial combination and polarization combination. Experiment results show that the optical power from fiber can reach to 120 W with a brightness of 9.1 MW/(cm2sr), and the electoral to optical efficiency is 45%, when operating current is 12 A.