Jpn. J. Appl. Phys. 43 (2004) pp. 5269-5272 |Previous Article| |Next Article| |Table of Contents|
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Single-Wavelength 5.6 kW Direct Diode Laser with a High-Efficiency Beam Combination
Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita, Shizuoka 434-8601, Japan
1Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871, Japan
(Received March 8, 2004; accepted April 30, 2004; published August 10, 2004)
Our group developed a new optical system equipped with a slit mirror to combine the output power from two LD stack modules (30 bars each) and focus them into a single beam. The new device realized a CW output power of more than 3 kW with a transfer efficiency of 92%. Furthermore, by combining beams from two added stack modules to the main optical path using polarization coupling, we have achieved a CW output power of 5.6 kW with a single wavelength of 808 nm. The focused spot size was 2.4 mm×0.5 mm (the power intensity was 467 kW/cm2) at a practical focal length of 100 mm. The transfer efficiency from the LD output to the focal spot was estimated to be 86.5%. The total energy efficiency against the input electricity was approximately 45%. This value is the highest ever reported in a high-power LD applied to material processing, and a full threefold higher than that of the diode-pumped Nd:YAG laser, a device heretofore known to be highly efficient (at around 15%).
- S. Heinemann and L. Leininger:
Proc. SPIE 3267 (1998) 116[AIP Scitation].
- R. Göring, P. Schreiber and T. Poßner:
Proc. SPIE 3008 (1997) 202[AIP Scitation].
- H. G. Treusch, K. Du, M. Baumann, V. Sturm, B. Ehlers and P. Loosen:
Proc. SPIE 3267 (1998) 98[AIP Scitation].
- F. Daiminger, F. Dorsch and D. Lorenzen:
Proc. SPIE 3682 (1998) 13[AIP Scitation].
- N. Abe: Rev. Laser Eng. 31 (2003) 318.
- H. Miyajima, T. Uchiyama, Y. Wang, S. Oishi and H. Kan: Japan Patent Pending 2001-317017 (2001).
- X. Gao, H. Suzuki, M. Takasaka, Y. Ohbayashi and M. Saito: Japan Patent Pending 1997-230977 (1997).
- M. I. Nathan, W. P. Dumke, G. Burns, F. H. Dill, Jr. and G. Lasher:
Appl. Phys. Lett. 1 (1962) 63[AIP Scitation].
- F. Bachman: Proc. 4th Symp. Advanced Photon Proc. & Meas. Tech., 2000, p. 176.
- H. G. Treusch, A. Ovtchinnikov, X. He, M. Kanskar, J. Mott and S. Yang: IEEE J. Sel. Top. Quantum Electron. 6 (2000) 601.
- H. Miyajima, H. Kan, T. Kanzaki, S. Furuta, M. Yamanaka, Y. Izawa and S. Nakai: Opt. Lett. 29 (2004) 304.