Enhancement of wire diameter measurements: Comparison between Fraunhofer diffraction and Lorenz-Mie theory


LEBRUN D., BELAID S., Ozkul C. , REN K., GREHAN G.

OPTICAL ENGINEERING, cilt.35, ss.946-950, 1996 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 35 Konu: 4
  • Basım Tarihi: 1996
  • Doi Numarası: 10.1117/1.600703
  • Dergi Adı: OPTICAL ENGINEERING
  • Sayfa Sayıları: ss.946-950

Özet

The Fraunhofer diffraction is compared with a numerical simulation based on the Lorenz-Mie theory to improve the performance of a laser diffraction instrument. This instrument, based on the analysis of diffraction fringes at the focal plane of a lens, is especially suitable for individual wire diameter measurements. We show that the error due to Fraunhofer approximation increases with an increase of the reflectivity and a decrease of the object diameter. Comparison with Lorenz-Mie theory enables us to correct these errors. For a given object, the laser diffraction instrument reproduces diameter measurements with a very small dispersion. (C) 1996 Society of Photo-Optical instrumentation Engineers.