Comparison of fiber length analyzers

In recent years, several fiber new fiber length analyzers have been developed and brought to market. The new instruments provide faster measurements and the capability of both laboratory and on-line analysis. Do the various fiber analyzers provide the same length, coarseness, width, and fines measurements for a given fiber sample? This paper provides a comparison of fiber length analyzers over a range of fiber types. Integrated Paper Services, Inc., the USDA FS Forest Products Laboratory, and the Paper Science Department at UW-Stevens Point evaluated six distinct pulp samples using the FS-200, Fibermaster, MorFi, Fiber Lab, FQA (Fiber Quality Analyzer) and HI Res FQA analyzers. Each optical fiber length instrument studied provides repeatable measurements for fiber length, coarseness, width, and fines. However, there were measurement differences between the instruments. Given the fact that the various instruments have unique hardware and software, these measurement differences were expected. Fiber length, width, and coarseness, and fines measurements generally correlate well between instruments indicating that calibration between instruments is possible. Fines measurements do not correlate between the MorFi and the other instruments because the MorFi measures and reports fines on a different basis.