photoelectric smoke detector



  • A smoke detector that incorporates a photoelectric device. In such a device, for instance, a light source and a photosensitive device may be arranged in a manner that the rays from said source ordinarily do not strike the sensor. When particles of smoke cross the path of the light rays, light scattered by said smoke makes some of the light fall upon the sensor. Alternatively, the light beam may be directed at the sensor, and light scattered by the smoke reduces the intensity of the light reaching the detector. Also spelled photo-electric smoke detector. Also called projected-beam smoke detector.
  • synonymprojected-beam smoke detector