Forensic Examination of Bulb Filaments by the Sem

  • Knud Aage Thorsen


The evaluation of vehicle lighting conditions at the time of an accident is an important forensic task that is accomplished by examination of lamp and lamp remains. Optical and scanning electron microscopy are complementary analytical techniques with growing importance of the latter, due to its high resolution, large depth of focus and the EDS microanalysis option. In order to make light bulb analysis less of an analytical art and more of a reliable investigative technique, a thorough understanding of bulb design, the materials systems used and the functioning of a bulb and its behaviour under impact has to be acquired. In this review an attempt has been made to collect the comprehensive but widely scattered literature relevant in these respects. Case stories are presented ob bulb cases solved with the SEM under reference to the above points of view.


Tungsten Wire Filament Wire Support Post Soret Effect Thermal Etching 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Knud Aage Thorsen
    • 1
  1. 1.Department of MetallurgyThe Technical University of DenmarkLyngbyDenmark

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