Share Email Print
cover

Proceedings Paper

Experimental research on mechanism of phase noise of laser amplifier
Author(s): Lei Liu; Yang Liu; Kun Zhang; Xiao-jun Tang; Chao Wang; Hong Zhao
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Coherent combination of multiple laser amplifier is an important technique for high power and high beam quality laser. Laser amplifier uses master oscillator power amplifier (MOPA) configuration for narrow bandwidth and high beam quality laser. Then active phase control is used to make multiple laser amplifier phase synchronization for coherent spot in the far field. The center spot is N times brighter than the one of incoherent combination. At present, researchers have used this method to achieve 1.56kW coherent combination of nine fiber lasers and 105kW of seven slab lasers. The phase noise of the laser amplifier is an important factor affecting the coherent combination. There are two key technologies in the coherent combination. The one is fill factor of multiple laser spatial distribution, which determines main lobe energy of coherent spot. And the other is the phase noise of the laser amplifier, which decides stability of the coherent combination. The phase noise of laser amplifier is caused by many factors, mainly thermal disturbance and mechanical vibration. Due to the complexity of the phase noise generation, the research on phase noise is generally concentrated in the qualitative analysis. The phase noise is generally considered the time phase noise. It is phase dithering from variation refractive index by external disturbance. A variety of factors, such as temperature changes, mechanical vibrations, the pump power, affect phase noise. We establish an externally imposed discrete disturbance source on fiber laser amplifier and then analyze above-mentioned factors independently and quantitatively by the method. The experiments demonstrate space phase noise, dithering of beam direction, is simultaneously induced by either mechanical vibration or thermal disturbance. This experiment is significant for understanding mechanism of the phase noise and suppression of phase noise.

Paper Details

Date Published: 17 September 2013
PDF: 7 pages
Proc. SPIE 8904, International Symposium on Photoelectronic Detection and Imaging 2013: High Power Lasers and Applications, 89040Z (17 September 2013); doi: 10.1117/12.2034099
Show Author Affiliations
Lei Liu, North China Research Institute of Electro-Optics (China)
Yang Liu, North China Research Institute of Electro-Optics (China)
Kun Zhang, North China Research Institute of Electro-Optics (China)
Xiao-jun Tang, North China Research Institute of Electro-Optics (China)
Chao Wang, North China Research Institute of Electro-Optics (China)
Hong Zhao, North China Research Institute of Electro-Optics (China)


Published in SPIE Proceedings Vol. 8904:
International Symposium on Photoelectronic Detection and Imaging 2013: High Power Lasers and Applications
Andreas Tünnermann; Zejin Liu; Pu Wang; Chun Tang, Editor(s)

© SPIE. Terms of Use
Back to Top