Abstract
The power scaling of narrow-band and near-diffraction-limited solid state laser radiation by spectral beam combining has been demonstrated during the last years with high efficiencies > 90 % [1,2] in large multiplexing modules (l ≈ 1 m). We present a diode laser prototype based on a compact dense wavelength division multiplexer (DWDM) for diode laser bars with low average beam quality (M2 = 45). The prototype with a radiance of 70 GW/(m2sr) (without polarization coupling, at an injection current of I = 120 A) consists of five spectrally stabilized and passively cooled diode laser bars with the center wavelengths 973 nm, 974.5 nm, 976 nm, 977.5 nm and 979 nm. To achieve a good stabilization performance ELOD (Extreme LOw Divergence) diode laser bars have been chosen [3,4]. The spectral width defined by 95 % power inclusion is < 0.6 nm for each beam source across the entire operating range from 30 A to 120 A. Due to the spectral stabilization the output power of each bar changes in the range of ± 5 %. Near the threshold current and at high injection currents (100 A to 120 A) the output power of the stabilized diode laser bar slightly increases compared to the free running diode laser. A beam transformation with a pair of step mirrors adapts the beam quality in both axes before the radiation enters the multiplexer.
© 2013 IEEE
PDF ArticleMore Like This
B. Chann, A. K. Goyal, A. Sanchez-Rubio, T.Y. Fan, B. L. Volodin, and V. S. Ban
CMD6 Conference on Lasers and Electro-Optics (CLEO:S&I) 2006
Staffan Tjörnhammar, Valdas Pasiskevicius, and Fredrik Laurell
JTh2A.06 Advanced Solid State Lasers (ASSL) 2013
U. Witte, D. Rubel, M. Traub, M. Hamann, S. Hengesbach, and D. Hoffmann
AF1A.6 Advanced Solid State Lasers (ASSL) 2015