LASER LIGHT INTERACTION FOR TEXTURE EVALUATION OF NATIVE WOODS AND Eucalyptus grandis W. Hill ex Maiden
DOI:
https://doi.org/10.5902/198050981834Keywords:
“speckle”, laser light, wood texture.Abstract
This work had the objective of study in patterns of the “speckle” as function of the wood texture of Bowdichia virgilioides (sucupira), Swietenia macrophylla (mogno), Balfourodendron riedelianum (pau-marfim) and Eucalyptus grandis wood. The He-Ne laser 10 mW was used to illuminate the wood samples and a digital camera captured the result of the interaction of the wood with the laser light. The results obtained from image analysis were compared with the pattern obtained by microscopic methodology. The captured images show the intensities of each pixel, varying between 0 and 255 in the gray scale. From the images, a central area of 16x16 pixels was removed and analyzed by the application of the convolution function and its Fourier Transform, resulting in the power density spectrum. The results showed that the information obtained by the power density spectrum of the “speckle” space variation allow classing samples of woods with different texture.
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References
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