The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 22, 2022
Filed:
Sep. 26, 2019
Siemens Schweiz Ag, Zürich, CH;
Thomas Bachels, Benzenschwil, CH;
Mathias Staeger, Menzingen, CH;
SIEMENS SCHWEIZ AG, Zurich, CH;
Abstract
Various embodiments include a scattered light smoke detector comprising: a two-color LED for emitting light of a first wavelength and a second wavelength; a photosensor spectrally matched with said two-color LED; and a control unit connected to the two-color LED and to the photosensor. The control unit is configured to control the two-color LED to emit light of the first wavelength or the second wavelength and to detect a photosensor signal of the photosensor. The control unit is further configured to analyze the photosensor signal for a first scattered radiation intensity and a second scattered radiation intensity allocated respectively to the first wavelength and the second wavelength. There is a polarizer optically connected upstream of the photosensor or downstream of the two-color LED. The polarizer polarizes light passing through at different intensities in dependence upon the respective wavelength of said light.