Fibre orientation determn. - using varied orientation of test piece and microwave beam to give alignment without contact or damage to test material

摘要

To determine the orientation of fibres in a variety of materials, without damage or contact with the material, the orientation of the test piece is varied in a quasi optical microwave measurement zone in relation to the field strength vector of the beam. The resulting signal changes give the deg. of orientation and the mean orientation alignment of the fibres in the test piece. The measured signal run is pref. developed by rotating the transmitter and/or receiver in relation to the test piece, or the relative orientation is provided by rotating the test piece. The relative orientation can also be provided by rotating the direction of polarisation under electrical control. The transmission measurement at the front side is through a suitable mirror placed in position. A local assessment of the deg. of fibre orientation is provided by a beam limiter, to allow a screening of the sample in one or two dimensions. ADVANTAGE - The system can be set to match the geometry of the test piece to increase the range of quality checks which can be performed.