MEASURING THE FIBRIL ANGLE OF FIBERS USING CONFOCAL MICROSCOPY

A new technique for measuring the S2 fibril angle in wood fibres using a confocal microscope in reflectance mode is presented. Polarized las er light is reflected from the fibre and passed through an analyser po laroid crossed with the polarization of the illuminating laser beam Th e measured intensity goes through a minimum whenever the orientation o f the fibrils matches the polarization of either the incoming laser li ght or the analyser As the confocal optics of the microscope allows de fection of only light scattered from on or around the focal plane of t he microscope, optical. interference from the second fibre wall is eli minated. Thus the fibril angle can be measured without extensive sampl e preparation. A number of examples of the new method are presented.