OPTICAL SECTIONING OF PULP FIBERS USING CONFOCAL SCANNING LASER MICROSCOPY

Fiber coarseness or wall thickness is an important marker of pulp quality because it affects how fibers respond to papermaking treatments and influences most end-use properties of paper and board products. Confocal microscopy is a powerful new technique that is being widely used to study three-dimensional form and structure. Specimen preparation is simple. Optical sectioning with a confocal scanning laser microscope rapidly generates nondestructive cross-sectional images of wood pulp fibers. Image analysis is then used to determine fiber cross-sectional area, perimeter, and wall thickness, from which coarseness can be calculated. For fiber analysis, the technique is superior to measurement methods that provide only average values and furnish no information on how coarseness is distributed.