EP 0005352 A1 19791114 - Radiation detection intruder alarm apparatus.
Title (en)
Radiation detection intruder alarm apparatus.
Title (de)
Einrichtung zur Meldung von Einbruch durch Strahlungsdetektion.
Title (fr)
Dispositif d'alarme anti-intrusion par détection de radiation.
Publication
Application
Priority
GB 1683278 A 19780427
Abstract (en)
Radiation detection apparatus includes a first detector (6) for detecting radiation at a wavelength which is preferably in the infra-red region, and means for sensing the presence of an obturating element (11), which element acts to prevent operating of the first detector. The sensing means includes a transmitter (14) which transmits a signal at a second wavelength, and a second detector (15) responsive to and arranged to receive the signal in the presence of the obturating element, preferably by reflection of the signal from the element. An alarm (10) may be activated in response to detection of radiation or of the transmitted signal.
IPC 1-7
IPC 8 full level
G08B 13/193 (2006.01); G08B 29/04 (2006.01)
CPC (source: EP)
G08B 13/193 (2013.01); G08B 29/046 (2013.01)
Citation (search report)
PROCEEDINGS 1973 CARNAHAN CONFERENCE ON ELECTRONIC CRIME COUNTERMEASURES, April 25-27, 1973 Kentucky (US) F. SCHWARZ: "Design and application of a wide field, passive, infrared intrusion detector", pages 138-144 * page 140, left-hand column, line 7 to page 141, left-hand column, line 33; page 142, left-hand column, line 28 to right-hand column, last line *
Designated contracting state (EPC)
BE CH DE FR IT LU NL SE
DOCDB simple family (publication)
DOCDB simple family (application)
EP 79300724 A 19790427; GB 1683278 A 19780427