Coherent beam combination with single frequency dithering technique.
The single frequency dithering technique for coherent beam combination with one single modulation frequency and without a reference beam is presented for the first time to our knowledge. Coherent beam combination of four fiber amplifiers is successfully demonstrated by using the single-dithering technique. When the phase control system is in the closed loop, the fringe contrast of far-field intensity pattern is improved by more than 85% from 8% in open loop, and the residual phase error is less than lambda/20. Experimental results reveal that the single-dithering technique has great potential in scaling to a large number of beamlets with a simple phase control system and low cost.
Ma
Yanxing
Y
College of Opticelectric Science and Engineering, National University of Defense Technology, Changsha 410073, China.
Zhou
Pu
P
Wang
Xiaolin
X
Ma
Haotong
H
Xu
Xiaojun
X
Si
Lei
L
Liu
Zejin
Z
Zhao
Yijun
Y