Measurement of light reflection, transmission, and dispersion qualities of web materials - by measuring the amt. of fleck beam reflected from the material

摘要

Arrangement for checking the optical quality of reflective and transparent materials by an optical measurement technique using at least one illumination unit (1) and at least one receptor/evaluation unit (3.1,3.2), novel in that (i) one or more illumination units are placed in front of, above and/or under the test material (2.1,2.2), with an adjacent transparent body (40) having a light obscuring patch (4.1) arranged to produce a fleck beam, and (ii) at least one receptor/evaluation unit (3.1,3.2) is installed, by which the light reflected, refracted, or dispersed by the test material (2.1,2.2) is measured by at least a detector preceded by a pin-hole stop, or a computer enhanced imaging CCTV camera, and where the fleck beam is incident on the test material at an angle of 0-85 deg. USE/ADVANTAGE - Monitoring of manufactured quality of light reflective and transmitting materials, and especially quality control of paper, such as photographic printing and other transparent plastics coated/laminated papers. Rapid, reproducible measurements which are less susceptible to distortion by superficial variations, and free of subjective influence.