VORRICHTUNG ZUM OPTISCHEN NACHWEIS VON SCHWEBETEILCHEN

摘要

The device serves for the optical detection of suspended particles. The radiation from a source (2) is polarised via a liquid-crystal cell (4) in a temporally periodic fashion in two mutually perpendicular planes ( phi @, phi PARALLEL ). The radiation scattered by the suspended particles in the chamber (1) and situated in these planes is used to generate a signal which is proportional to the degree of polarisation of the scattered radiation and depends linearly on the mean diameter @ of the particles. By logical combination (13, 14) of this signal with a signal proportional to the scattered radiation, a signal is produced which is proportional to the product of @ and the number n of particles. The device is applied in display units for suspended particles. <IMAGE>