VERFAHREN UND VORRICHTUNG ZUM FESTSTELLEN VON FREMDKOERPERN IN FLUIDEN.

摘要

Fluid in a flask (7) positioned between a polariser (16) and analyser (17) is illuminated by a lamp (2) through two windows (13) in a mask (9) while the flask is rotated (27) on a turntable with a revolution counter (6). A video camera (21) is connected to an image processor (22) and monitor (30). The intensity of transmitted light in the vicinity of the optical axis is sampled optoelectronically and compared with an adjustable threshold. Measured values exceeding the threshold identified, and corresp. signals are produced.