Patent ID: 9678008
Date: 2017-06-13
CPC Classifications: G01N

Claim:
1. A device for measuring scattered light from a measurement volume with compensation for background signals, comprising at least one light sensor having at least two separately evaluable light-sensitive elements, a single imaging optical system, wherein the light-sensitive elements are arranged in the image plane and the measurement volume is arranged in the corresponding object plane of the optical system, the visual ranges of the light-sensitive elements are completely separate from each other in the object plane and overlap each other behind the object plane, a light transmitter with a collimated light beam, which only passes through, or at least primarily passes through, the visual range of the one light-sensitive element within an area extending through the object plane and bordering the measured volume such that this light-sensitive element detects scattered light from the measurement volume and background light from the overlapping visual ranges behind the subject plane, and the other light-sensitive element detects no or significantly less scattered light from the measurement volume and background light from the overlapping visual areas behind the object plane, and a diaphragm that is arranged between the optical system and the light-sensitive elements that restricts the visual ranges of the light-sensitive elements behind the object plane such that the areas of the two visual ranges which do not overlap each other are partially or completely hidden.