公开(公告)号：EP4174814A1

公开(公告)日：2023-05-03

申请号：EP21204785.6

申请日：2021-10-26

申请人： Carrier Fire & Security EMEA BV

发明人： MANSFELD, Sebastian ,  MILEK, Tadeusz ,  SULKOWSKI, Lukasz ,  MORUSIEWICZ, Marcin

IPC分类号： G08B29/04 ,  G08B13/193

摘要： A motion detector (1) for a security system comprises a primary sensing system including a PIR sensor (5) configured to detect movement of a person within a monitored environment (2), and an ancillary sensing system including a first emitter (7), a second emitter (8) and a receiver (9) configured to detect masking of the primary sensing system.
Masking by an object (10) in the monitored environment (2) is determined using the first emitter (7) and the receiver (9) based on a time-of-flight of an optical signal emitted into the monitored environment (2) and reflected by the object (10). Masking by obscuring of a window (4) of the motion detector (1) is determined using the second emitter (8) and the receiver (9) based on the intensity of light transmission from the second emitter (8) through the window (4) to the receiver (9).