Laser extinction measuring device - measures high dust concentrations using laser beam and laser line filter removing extraneous light

摘要

The device measures dust content of gases in gas channels. It utilises the properties of a laser beam, such as high light intensity, small beam divergence and monochromatic light. It, therefore, makes possible direct and continuous measurement of high dust concentrations ingas channels with any desired dia. The whole channel dia. can be used for measurement even with large channels. The monochromatic light makes possible the use of a laser line filter, so that the device is very insensitive to generally disturbing external light.