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

被引：82

作者：

Koch M. ^{[1
,4
]}

Hunsche S. ^{[3
]}

Schuacher P. ^{[2
]}

Nuss M.C. ^{[3
]}

Feldmann J. ^{[1
]}

Fromm J. ^{[2
]}

机构：

[1] Inst. für Koch Frequenatechnik, Tu Braunschweig, 33106 Braunschweig

[2] Institut für Holzforschung, Ludwig-Maximilians-Universität, 80797 München

[3] Bell Laboratories, Lucent Technologies, Holmdel, NJ 07733

[4] Lehrst. Photonik und Optoelektronik, Sektion Physik, 80799 München

来源：

Wood Science and Technology | 1998年 / 32卷 / 6期

关键词：

Spectroscopy; Density Mapping; Spectral Range; Measured Absorption; Wood Density;

D O I：

10.1007/BF00702799

中图分类号：

学科分类号：

摘要：

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.

引用

页码：421 / 427

页数：6

共 16 条

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