| 摘要 |
PROBLEM TO BE SOLVED: To provide a smoke sensor which presents an effect of ambient light and requires no alignment of optical axis. SOLUTION: The smoke sensor (1) includes: an imaging part (11) for capturing an image; at least a first light source (20a) and a second light source (20b) arranged in an imaging range (ARE) of the imaging part (11) so as to face the imaging part (11); and a signal processing part (12) for allowing the imaging part (11) to image the first and second light sources (20a, 20b) and process imaging signals output according to the light quantities of the first and second light sources (20a, 20b). The first light source (20a) emits light of a first wavelength range, the second light source (20b) emits light of a second wavelength range including a part of a first wavelength range or different from the first wavelength range. The signal processing part (12) detects a change in imaging signal level output from the imaging part (11), and when the imaging signal level is outside a prescribed range, outputs a sensing signal showing that smoke is sensed. COPYRIGHT: (C)2010,JPO&INPIT |
