OSA's Digital Library

Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 48, Iss. 27 — Sep. 20, 2009
  • pp: 5190–5196

Hardware accelerated optical alignment of lasers using beam-specific matched filters

Abdul A. S. Awwal, Kenneth L. Rice, and Tarek M. Taha  »View Author Affiliations

Applied Optics, Vol. 48, Issue 27, pp. 5190-5196 (2009)

View Full Text Article

Enhanced HTML    Acrobat PDF (345 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Accurate automated alignment of laser beams in the National Ignition Facility (NIF) is essential for achieving extreme temperature and pressure required for inertial confinement fusion. The alignment achieved by the integrated control systems relies on algorithms processing video images to determine the position of the laser beam images in real time. Alignment images that exhibit wide variations in beam quality require a matched-filter algorithm for position detection. One challenge in designing a matched-filter-based algorithm is to construct a filter template that is resilient to variations in imaging conditions while guaranteeing accurate position determination. A second challenge is to process images for thousands of templates in under a second, as may be required in future high-energy laser systems. This paper describes the development of a new analytical template that captures key recurring features present in the beam image to accurately estimate the beam position under good image quality conditions. Depending on the features present in a particular beam, the analytical template allows us to create a highly tailored template containing only those selected features. The second objective is achieved by exploiting the parallelism inherent in the algorithm to accelerate processing using parallel hardware that provides significant performance improvement over conventional processors. In particular, a Xilinx Virtex II Pro field programmable gate array (FPGA) hardware implementation processing 32 templates provided a speed increase of about 253 times over an optimized software implementation running on a 2.2 GHz AMD Opteron core.

© 2009 Optical Society of America

OCIS Codes
(070.5010) Fourier optics and signal processing : Pattern recognition
(220.1140) Optical design and fabrication : Alignment
(100.3008) Image processing : Image recognition, algorithms and filters
(140.3538) Lasers and laser optics : Lasers, pulsed
(100.4999) Image processing : Pattern recognition, target tracking
(150.5758) Machine vision : Robotic and machine control

ToC Category:
Fourier Optics and Signal Processing

Original Manuscript: February 10, 2009
Revised Manuscript: August 31, 2009
Manuscript Accepted: September 1, 2009
Published: September 15, 2009

Abdul A. S. Awwal, Kenneth L. Rice, and Tarek M. Taha, "Hardware accelerated optical alignment of lasers using beam-specific matched filters," Appl. Opt. 48, 5190-5196 (2009)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. E. I. Moses and C. R. Wuest, “The National Ignition Facility: laser performance and first experiments.,” Fusion Sci. Technol. 47, 314-322 (2005).
  2. E. Bliss, M. Summers, F. Holloway, and B. Johnson, “Shiva alignment systems,” J. Opt. Soc. Am. 68, 547-547 (1978).
  3. E. Stout, V. Miller-Kamm, J. Spann, and P. Van Arsdall, “Prototype distributed object-oriented architecture for image-based automatic laser alignment,” Proc. SPIE 3047, 214-221(1997).
  4. R. A. Zacharias, N. R. Beer, E. S. Bliss,et al., “Alignment and wavefront control systems of the National Ignition Facility,” Opt. Eng. 43, 2873-2884 (2004). [CrossRef]
  5. K. Wilhelmsen, A. Awwal, W. Ferguson, B. Horowitz, V. Miller Kamm, and C. Reynolds, “Automatic alignment system for The National Ignition Facility,” Proceedings of 2007 International Conference on Accelerator and Large Experimental Control Systems (ICALEPCS07), 486-490 (ICALEPCS, 2007), http://accelconf.web.cern.ch/accelconf/ica07/PAPERS/ROAA02. PDF
  6. C. A. Haynam, P. J. Wegner,et al., “National Ignition Facility laser performance status,” Appl. Opt. 46, 3276-3303(2007). [CrossRef] [PubMed]
  7. National Ignition Facility and Photon Science, “LIFE: clean energy from nuclear waste,” https://lasers.llnl.gov/missions/energy_for_the_future/life/.
  8. R. Irwan and R. G. Lane, “Analysis of optimal centroid estimation applied to Shack-Hartmann sensing,” Appl. Opt. 38, 6737-6743 (1999). [CrossRef]
  9. Z. Jiang, S. Gong, and Y. Dang, “Numerical study of centroid detection accuracy for Shack-Hartmann wavefront sensor,” Opt. Laser Technol. 38, 614-619 (2006). [CrossRef]
  10. J. Arines and J. Ares, “Minimum variance centroid thresholding,” Opt. Lett. 27, 497-499 (2002). [CrossRef]
  11. S. Chang and C. P. Grover, “Centroid detection based on optical correlation,” Opt. Eng. 41, 2479-2486 (2002). [CrossRef]
  12. A. A. S. Awwal, Wilbert A. McClay, W. S. Ferguson, J. V. Candy, T. Salmon, and P. Wegner, “Detection and tracking of the back-reflection of KDP images in the presence or absence of a phase mask,” Appl. Opt. 45, 3038-3048 (2006). [CrossRef] [PubMed]
  13. A. A. S. Awwal, K. L. Rice, and T. M. Taha, “Fast implementation of matched-filter-based automatic alignment image processing,” Opt. Laser Technol. 41, 193-197 (2009). [CrossRef]
  14. A. A. S. Awwal, R. Leach, K. L. Rice, and T. M. Taha, “Higher accuracy template for corner cube reflected image,” Proc. SPIE 7072, 70720V (2008). [CrossRef]
  15. A. B. Vander Lugt, “Signal detection by complex spatial filtering,” IEEE Trans. Inf. Theory 10, 139-145 (1964). [CrossRef]
  16. J. L. Horner and J. Leger, “Pattern recognition with binary phase-only filters,” Appl. Opt. 24, 609-611 (1985). [CrossRef] [PubMed]
  17. A. A. S. Awwal, M. A. Karim, and S. R. Jahan, “Improved correlation discrimination using an amplitude-modulated phase-only filter,” Appl. Opt. 29, 233-236 (1990). [CrossRef] [PubMed]
  18. M. A. Karim and A. A. S. Awwal, Optical Computing: An Introduction (Wiley, 1992).
  19. A. Awwal, S. W. Ferguson, and C. Law “Uncertainty detection for NIF normal pointing images,” Proc. SPIE 6695, 66950R (2007). [CrossRef]
  20. “FFT code and related material,” http://www.jjj.de/fft.

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.


Fig. 1 Fig. 2 Fig. 3
Fig. 4 Fig. 5

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited