Smoke detector utilizing ambient-light sensor, external sampling volume, and internally reflected light

摘要

In accordance with certain embodiments, a smoke detector utilizes a reflected-light signal and sensed ambient light to determine the presence of smoke particles.

主权项

1. A smoke detector comprising:
a housing; disposed within the housing, a light source configured to (i) direct light outside of the housing, and (ii) emit an interior portion of light within the housing substantially without emission therefrom; disposed within the housing, one or more light detectors configured to detect light from the light source that is reflected back into the housing, at least one said detector being configured to detect light from the interior light portion within the housing; disposed at least partially within or on the housing, an ambient-light sensor for sensing an ambient light level outside of the housing; and an evaluation circuit for determining the presence of smoke particles outside the housing based at least in part on (a) the detected light, (b) a luminance of light detected from the interior light portion, and (c) at least one of (i) the sensed ambient light level or (ii) a temporal evolution of the sensed ambient light level.