摘要 |
1. An optical smoke sensor comprising a light source (S) and a light detector (E) arranged at an acute angle (beta) in relation thereto, where the overlap zones of the transmitting lobe (SK) and the receiving lobe (EK) form a measurement zone (MR) in which smoke particles present produce a scattering of light to be received as reflected radiation, wherein the detector (E) is assigned at least one light source (S1, S2) in its direct vicinity, characterised in that a non-scattered light beam (SK1, SK2) which emanates from the light source emerges through an opening (O1, O2) in the housing (G) of the sensor (M), where the angle (alpha) of the transmitting lobe (SK) is at least sufficiently small to correspond to the outlet opening (O), and where the housing has no opening at the point to which the receiving lobe (EK) extends. |