Abstract
As advancements in laser technology result in higher-power devices, increased thermal loads experienced by resonator optical components generate instabilities in the output beam. Consequently, methods for maintaining and optimizing output-beam parameters are necessary for efficient long-term operation. This study examines a vision-based feedback control system which monitors a sampled cross-sectional image of the laser's output, and regulates both cavity mirrors, as well as the excitation level, to stabilize beam uniformity, beam steer, and output-power level.
The system optimizes the output-power distribution achievable from a given laser, while significantly reducing beam steering effects. Direction of beam propagation is restricted to within 60 μrad of the desired setpoint, while the output power is stabilized to within 4%. Results clearly document a considerable improvement in laser performance through maximization of beam uniformity, minimization of beam steering, and stabilization of total output power. As such, an important degree of consistency and repeatability in output-beam parameters, essential to precision laser applications, is easily achieved. Valuable diagnostic capabilities pertaining to output beam intensity and energy profiles are also incorporated into the control system. These data may be monitored on-line or stored for subsequent analysis.
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References
Y. Arata: Proc. Int'l Conf. on Laser Advanced Materials Processing — Science and Applications, Osaka, Japan (1987)
Photon, Inc.: The Importance of Measuring the Spatial Characteristics of Optical Beams (Photon, Los Gatos, CA 1988)
C.V. Sellathamby, H.J.J. Seguin, S.K. Nikumb: Opt. Commun. 78, 47–50 (1990)
C.V. Sellathamby, H.J.J. Seguin, S.K. Nikumb: Appl. Opt. 29, 4499–4503 (1990)
A.J.B. Travis: Proc. 5th Int'l Symp. on Gas Flow and Chemical Lasers (1984) pp. 367–372
W.P. Latham, J.D. German: Laser Diagnostics, SPIE Proc. 343, 64–70 (1982)
T.J. Ramos, D.R. Lim, A.C. Lingenfelter: Proc. Medicine and Biology Symposium — ICALED '85, 152–157 (1985)
G.C. Lim, W.M. Steen: Proc. 1st Int'l Conf. on Lasers in Manufact., Brighton, U. K. (1983)
G. Sepold, P.O. Juptner, J. Telepski: High Power Lasers and Their Industrial Applications, SPIE Proc. 650, 167–169 (1986)
E. Beyer, G. Herrziger, R. Kramer, P. Loosen: High Power Lasers and Their Industrial Applications, SPIE Proc. 650, 170–177 (1986)
F.H. White, G.A. Needham: Laser Diagnostics, SPIE Proc. 343, 2–15 (1982)
J.T. Knudtson, K.L. Ratzlaff: Rev. Sci. Instrum. 54, 856–860 (1983)
V.M. Weerasinghe, W.M. Steen: Proc. Int'l Conf. on Applications of Lasers and Electro-optics — ICALED '85, 107–112 (1985)
W.M. Steen, V.M. Weerasinghe: High Power Lasers and Their Industrial Applications, SPIE Proc. 650, 160–165 (1986)
D.R. Akitt, H.J. Seguin, C.V. Sellathamby, H. Reshef: Rev. Sci. Instrum. 63, 1859–1866 (1992)
D.R. Akitt, H.J. Seguin, M.R. Cervenan, S.K. Nikumb: IEEE J. QE-26, 1413–1417 (1990)
F. Martin, J.G. Willman: Laser Focus/Electro. Opt. (USA) 21, 104–111 (1985)
G.P. Anderson: Using a Micro-computer to Measure the Intensity Distribution in a Laser Beam (Central Electricity Generating Board, New York 1987)
R.A. Heyler, S.C. Guggenheimer: Ion-Laser Technol. 8, 107–116 (1989)
V. Fantini, G. Incerti: High Power Lasers and Their Applications, SPIE Proc. 650, 36–38 (1986)
A.E. Siegman: Lasers (University of Science Books, Mill Valley, CA 1986) pp. 558–891
W.F. Krupke, W.R. Sooy: IEEE J. QE-5, 423–431 (1969)
K.H. Nam, H.J.J. Seguin, J. Tulip: IEEE J. QE-15, 44–50 (1979)
H.J.J. Seguin, K.H. Nam, J. Tulip: IEEE J. QE-15, 50–54 (1979)
A.K. Nath, H.J.J. Seguin, V.A. Seguin: IEEE J. QE-22, 268–727 (1986)
V.E. Merchant, M.R. Cervenan, H.J.J. Seguin: Proc. Int'l Conf. on Lasers '85, 642–646 (1985)
Productivity Tools for Optimizing Optical System Performance (Photon, Los Gatos, CA 1989)
C.V. Sellathamby, H.J.J. Seguin, D.R. Akitt, H. Reshef: Rev. Sci. Instrum.(to be published, 1993)
N.C. Kerr, S.E. Clark, D.C. Emmony: Rev. Sci. Instrum. 22, 1034–1036 (1989)
Thermal Image Plate for CO2 and Other Molecular Lasers (Optical Engineering, Inc., Santa Rosa, CA 1986)
S. Bangs: Welding Design and Fabrication, 45–48 (1984)
R.W. Richardson: Industrial Optical Sensing, SPIE Proc. 961, 95–113 (1988)
I. Ferrier: Robotics World 6, 22–24 (1988)
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Sellathamby, C.V., Seguin, H.J.J. & Akitt, D.R. Vision-based system for automatic stabilization of mode, beam steer, and output power of a high-power laser. Appl. Phys. B 57, 267–276 (1993). https://doi.org/10.1007/BF00325205
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DOI: https://doi.org/10.1007/BF00325205