Higher Accuracy Template for Corner Cube Reflected Image

Conference · Fri Jul 11 04:00:00 EDT 2008

DOI:https://doi.org/10.1117/12.798704· OSTI ID:945722

Awwal, A S; Rice, K L; Leach, R R; Taha, T M

Video images of laser beams are analyzed to determine the position of the laser beams for alignment purpose in the National Ignition Facility (NIF). Algorithms process beam images to facilitate automated laser alignment. One such beam image, known as the corner cube reflected pinhole image, exhibits wide beam quality variations that are processed by a matched-filter-based algorithm. The challenge is to design a representative template that captures these variations while at the same time assuring accurate position determination. This paper describes the development of a new analytical template to accurately estimate the center of a beam with good image quality. The templates are constructed to exploit several key recurring features observed in the beam images. When the beam image quality is low, the algorithm chooses a template that contains fewer features. The algorithm was implemented using a Xilinx Virtex II Pro FPGA implementation that provides a speedup of about 6.4 times over a baseline 3GHz Pentium 4 processor.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 945722
• Report Number(s): LLNL-CONF-405484
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
ACCURACY
ALGORITHMS
ALIGNMENT
DESIGN
IMPLEMENTATION
LASERS
OPTICS
US NATIONAL IGNITION FACILITY