TESTING OF LASER-DOPPLER TECHNIQUE FOR ME ASURING TEXTILE LENGTH

The measurement of the lengths of all kinds of textile materials by me ans of machines poses many problems to industry. The mechanical pick-r tp method still commonly used to determine the lengths of fabrics lead s to considerable measurement errors due to slip and the action of for ces. These errors can be clearly reduced by application of the non-con tact laser Doppler technique. The paper reports on the first practical rise of a laser Doppler length measuring instrument in measuring mach ines for textiles. The structure of the instrument and the measurement results obtained are presented and discussed.