Freeware | December 1, 2006

Full Article: Laser Ultrasonic Measurement Of Bending Stiffness On Moving Paper: A Mill Demonstration

Source: Polytec

A laser-based ultrasonic system for non-contact, in-process measurement of the elastic properties of paper was successfully tested at an operating paper mill with web speeds exceeding 20 m/s. The paper's flexural rigidity and out-of-plane shear rigidity were calculated from the frequency dependence of the phase velocity of ultrasonic waves generated in the moving paper by a pulsed Nd:YAG laser and detected with a Polytec Laser Vibrometer.