| 摘要 |
In a diffused radiation smoke detector (D), the power supply of the evaluation unit (A) and the signal feedback to said unit are carried out exclusively through an optical path owing to radiation guiding elements (L1, L2), whereas all electric components are provided in the evaluation unit (A) at a distance apart from the smoke detector (D). By means of collimation devices (4, 6) provided at the ends (3, 8) of the optical fibers a substantially parallel area of radiation, respectively reception having a small diameter is created, thereby reducing the disturbing radiation level in the smoke detector while enhancing the sensitivity. As the smoke detector (D) has no metal part, it is sensitive neither to temperature nor to corrosion and its utilization is particularly well adapted to an explosive environment and to an environment subjected to electric perturbations. |
