Microspectrophotometry of Wood Grain and Color

Authors

  • Howard James Swatland University of Guelph, Canada

DOI:

https://doi.org/10.24203/ajet.v9i1.6519

Keywords:

Microspectrophotometry, Colorimetry, Wood color, Wood grain

Abstract

A reflecting microscope spectrophotometer was used for the colorimetry of wood using CIE (Commission Internationale de l’Éclairage) chromaticity coordinates.  A microscope scanning stage and scanning with optical fibers were used to detect grain patterns. Ten exotic woods with a fine grain structure were tested because they are highly valued in the manufacture of musical instruments and furniture, and they had a wide range in color and grain structure. With lateral illumination (45°) of samples and a large measuring aperture, the results were comparable to those that might be obtained with a commercial colorimeter detecting diffuse Lambertian reflectance. With vertical illumination and coaxial photometry in a microscope, Fresnel reflectance was dominant. The best predictor of CIE x with lateral illumination was reflectance at 400 nm (r = - 0.916, P < 0.0005) and the relationship persisted with vertical illumination (r = -0.67, P < 0.025).   Scanning across woods at 520 nm with a microscope scanning stage, there were relationships of CIE x with scanning peak height (r = 0.75 P < 0.01).   In scanning across 6 cm of wood with optical fibers, there was a relationship of the number of reflectance peaks (from wood grain between dark lines) with peak width (r = - 0.89, P < 0.0005). Woods with a fine grain had numerous small peaks while woods with a coarse grain had a few wide peaks. Thus, there is a connection between the color and grain pattern of wood.

Author Biography

Howard James Swatland, University of Guelph, Canada

University Emeritus Professor

References

Hoadley, R.B. (1980). Understanding Wood. A Craftsman’s Guide to Wood Technology. Taunton Press, Connecticut. 256 pp.

Liu, S., Loup, C., Gril, J., Dumonceaud, O., Thibaut, A., and Thibaut, B. (2005). Studies on european beech (Fagus sylvatica L.). Part 1: Variations of wood colour parameters. Annals of Forest Science. 62 (7): 625-632. https://hal.archives-ouvertes.fr/hal-00546627/document

Moya, R. and Marin, J.D. (2011). Grouping of Tectona grandis (L.f.) clones using wood color and stiffness. New Forests, 2011-11, Vol.42 (3), p.329-345. https://link.springer.com/article/10.1007/s00226-014-0618-3

Meints, T ., Teischinger, A., Stingl, R. and Hansmann, C. (2017). Wood colour of central European wood species: CIELAB characterisation and colour intensification. European Journal of Wood and Wood Products, 75 (4):499-509. https://www.researchgate.net/publication/309444193_Wood_colour_of_central_European_wood_species_CIELAB_characterisation_and_colour_intensification

Viera, H.C., Silva, E., Dos Santos, J.X. , and Nisgoski, S. (2019). Wood colorimetry of native species of Myrtaceae from a Araucaria Forest. Floresta 49(2): 353. https://www.jstor.org/stable/e26921867

Yazaki, Y. (2015). Wood Colors and their Coloring Matters: A Review. Natural Product Communications 10(3):505-12. https://www.jstor.org/stable/e26921867

Swatland, H.J. (2017). A review of microcolorimetry for textile, food, dental and optoelectronic industries. Asian Journal of Engineering and Technology. 5: 140-151. https://www.ajouronline.com/index.php/AJET/article/view/5065

Swatland, H.J. (2018). Colourimetry of chromatic aberration. Quekett Journal of Microscopy 43: 307-314. https://www.researchgate.net/publication/330638074_Colourimetry_of_chromatic_aberration

Swatland, H.J. (1998). Computer Operation for Microscope Photometry. CRC Press, Boca Raton, Florida.

Williamson, S.J. and Cummins, H.Z. (1983). Light and Color in Nature and Art. John Wiley, New York. 488 pp.

Luostarinen, K. and Möttönen, V. (2004). Effect of growing site, sampling date, wood location in trunk and drying method on concentration of soluble proanthocyanidins in Betula pendula wood, with special reference to wood colour. Scandinavian Journal of Forest Research. 19 (3): 234-240.

Downloads

Published

2021-02-25

How to Cite

Swatland, H. J. (2021). Microspectrophotometry of Wood Grain and Color. Asian Journal of Engineering and Technology, 9(1). https://doi.org/10.24203/ajet.v9i1.6519