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THz-imaging: a new method for density mapping of wood

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Summary

This paper presents a new technique for fast and non-intrusive density mapping of wood based on far-infrared spectroscopy. The transmission of a piece of beech 1.7 mm thick is investigated between 0.1 and 2.5 THz. In this spectral range we find wood to be fairly transparent, but density inhomogeneities and structural details such as annual rings become visible in the transmission profile. The measured absorption correlates well with the wood density independently obtained by the gravitometric-volumetric method. Thus it finally becomes possible to transform the THz images into 2-dimensional density maps.

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Author notes

  1. M. Koch

    Present address: Lehrstuhl für Photonik und Optoelektronik, Sektion Physik, Ludwig-Maximilians-Universität, Amalienstr. 54, 80799, München, Germany

Authors and Affiliations

  1. Institut für Koch frequenatechnik, Tu Braunschweig, Schleinitesk 22, 33106, BraunSchweig, Germany

    M. Koch & J. Feldmann

  2. Institut für Holzforschung, Ludwig-Maximilians-Universität, Winzererstr. 45, 80797, München, Germany

    P. Schumacher & J. Fromm

  3. Bell Laboratories, Lucent Technologies, 101 Crawfords Corner Road, 07733, Holmdel, NJ, USA

    S. Hunsche & M. C. Nuss

Authors
  1. M. Koch
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  2. S. Hunsche
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  3. P. Schumacher
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  4. M. C. Nuss
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  5. J. Feldmann
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  6. J. Fromm
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Additional information

The skillful technical help of Mrs. M. Rinas is greatly appreciated.

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Koch, M., Hunsche, S., Schumacher, P. et al. THz-imaging: a new method for density mapping of wood. Wood Sci.Technol. 32, 421–427 (1998). https://doi.org/10.1007/BF00702799

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  • DOI: https://doi.org/10.1007/BF00702799

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