EP 0025983 A3 19810422 - ARRANGEMENT TO PREVENT FALSE ALARMS BY PASSIVE INFRARED-MOVEMENT SIGNALLERS
Title (en)
ARRANGEMENT TO PREVENT FALSE ALARMS BY PASSIVE INFRARED-MOVEMENT SIGNALLERS
Publication
Application
Priority
DE 2937923 A 19790919
Abstract (en)
[origin: US4307388A] In an infrared motion alarm an optical filter arranged in front of an input of an infrared detector is attached to a heat sink in the form of a solid metal crucible in order to reduce the sensitivity to glass-penetrating electromagnetic radiation. Changes in radiation absorbed in the optical filter are either captured in the thermal sink or decelerated at least as to the characteristic thermal radiation of the optical filter and no longer fall within the characteristic range of change of the motion alarm.
IPC 1-7
IPC 8 full level
G08B 13/00 (2006.01); G08B 13/19 (2006.01); G08B 13/193 (2006.01); G08B 29/18 (2006.01)
CPC (source: EP US)
G08B 13/19 (2013.01 - EP US); G08B 13/193 (2013.01 - EP US); G08B 29/18 (2013.01 - EP US); Y10S 250/01 (2013.01 - EP)
Citation (search report)
- DE 2103909 A1 19710819 - OPTICAL COARING LAB INC
- DE 2836462 A1 19800306 - WOERL ALARM AUGUST WOERL INHAB
- FR 2080963 A1 19711126 - OPTICAL COATING LABORATORY INC
- US 2278936 A 19420407 - LINDSAY MAXWELL H A, et al
- US 3188830 A 19650615 - COWANS KENNETH W
Designated contracting state (EPC)
AT BE CH FR IT NL SE
DOCDB simple family (publication)
EP 0025983 A2 19810401; EP 0025983 A3 19810422; BR 8005968 A 19810331; DE 2937923 A1 19810611; DE 2937923 C2 19840524; GB 2059056 A 19810415; GB 2059056 B 19830824; JP S5652791 A 19810512; US 4307388 A 19811222
DOCDB simple family (application)
EP 80105602 A 19800918; BR 8005968 A 19800918; DE 2937923 A 19790919; GB 8029898 A 19800916; JP 13002780 A 19800918; US 15783180 A 19800609