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US 7,248,173 B2Granted
Smoke detector
AssigneeNittan Company, Limited
InventorsRyoichi Yamasaki, Takeshi Ueno, Yasunori Oya
Life of this patent
Estimating the term…
Abstract
A dark chamber is adapted to accommodate smoke particles. A photo emitter and a photo detector are disposed in the dark chamber. In a first region, a region where light emitted from the photo emitter passes and a region where the photo detector is capable of detecting light are overlapped, so that light emitted from the photo emitter and scattered by the smoke particles is detected by the photo detector. A photo converger converges light passed through the first region at a second region where is an outside of the first region.
Claims8
A smoke detector, comprising:
- a dark chamber, adapted to accommodate smoke particles;
- a photo emitter, disposed in the dark chamber;
- a photo detector, disposed in the dark chamber;
- a first region, at which an illumination region where light emitted from the photo emitter passes and a light detecting region where the photo detector is capable of detecting light are overlapped, so that light emitted from the photo emitter and scattered by the smoke particles is detected by the photo detector;
- and
- a reflective photo converger, which converges light passed through the first region at a second region which is located outside of the first region.
3 more elements
Dependencies are inferred from the claim text.