Method for characterizing fibrous materials using stokes parameters

Abstract

An apparatus (200) for determining fiber orientation parameters of a sheet of material during a production process includes a polarized radiation generating system (201, 202) operable for providing polarized radiation having a frequency of at least 1×108 Hz. The radiation is aligned to be incident on a sheet of material to be characterized (203). A polarimeter (204, 205) is aligned to receive the radiation transmitted by the sheet of material (203). A photodetector (206) is provided for measuring radiation received after polarization processing by the polarimeter. A processor (207) is coupled to the photodetector (206) for calculating Stokes parameters of the moving sheet (203) based upon intensities of the radiation received and determines at least one parameter relating to fiber orientation of the moving sheet based upon the Stokes parameters.

Dependencies are inferred from the claim text.