High Contrast Visualization of Short Fibers in a Concentrated Fiber Suspension

Abstract

Short fibers in a concentrated fiber suspension are visualized in a high contrast with a suspending fluid. The concentrated fiber suspension becomes transparent by employing an optimal index-of-refraction match of fibers and suspending fluids. Moreover, vinylon fibers as tracers are added to the fiber suspension because vinylon fibers having birefrigence are clearly observed using a transmitted light under crossed nicols.