Global Patent Index - EP 1265205 B1

EP 1265205 B1 20050119 - Linear smoke detector

Title (en)

Linear smoke detector

Title (de)

Linearer Rauchmelder

Title (fr)

Détecteur de fumée linéaire

Publication

EP 1265205 B1 20050119 (DE)

Application

EP 01114103 A 20010609

Priority

EP 01114103 A 20010609

Abstract (en)

[origin: EP1265205A1] The device transmits a light beam along a measurement path. A retroreflector rotates the polarization plane of an incident light beam by a defined angle. An active polarizer between transmitter and a receiver is associated with an analyzer transmissive for light with a defined polarization plane and performs controlled rotation of the polarization plane in two different planes. The receiver combines the received signals caused by light in these two planes. <??>The device has a transmitter (1) of a light beam along a measurement path, a receiver (2) and a retroreflector (3) that rotates the polarization plane of an incident light beam by a defined angle. An active polarizer (4) in the beam path after the transmitter and before the receiver is associated with an analyzer (5) transmissive for light with a defined polarization. The polarizer performs controlled rotation of the polarization plane in two different planes and the receiver combines the received signals caused by light in these two planes. <??>An Independent claim is also included for a method of operating a smoke alarm.

IPC 1-7

G08B 17/12; G08B 17/103

IPC 8 full level

G08B 17/103 (2006.01)

CPC (source: EP)

G08B 17/103 (2013.01)

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

DOCDB simple family (publication)

EP 1265205 A1 20021211; EP 1265205 B1 20050119; AT E287568 T1 20050215; DE 50105124 D1 20050224

DOCDB simple family (application)

EP 01114103 A 20010609; AT 01114103 T 20010609; DE 50105124 T 20010609