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:
Oct. 05, 2010
Filed:
Feb. 20, 2006
Matthieu Richard, Fourcatier, FR;
Matthieu Richard, Fourcatier, FR;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The obstruction detection device for an infrared intruder detection system comprises at least one transparent facet having a roughened surface; a light emitter arranged for emitting light towards the roughened surface; a light detector arranged for detecting the intensity of light, which is transmitted or reflected or diffracted by the roughened surface into a specific direction of space; and an output device for outputting an alarm-signal, when an absolute difference between the intensity of the detected light and a reference value exceeds a threshold value. A liquid or spray applied onto the roughened surface changes its scattering patterns. This change triggers the alarm-signal.