Combination photoelectric and ionization smoke detector

摘要

An ionization chamber for use in a smoke detector includes first and second outer electrodes and a non-reflective center electrode. The non-reflective center electrode can be formed as a metal electrode having a non-reflective coating or as a non-reflective, conductive plastic elements. The ionization chamber can be incorporated into combination smoke detector which includes a photoelectric sensor. A non-reflective center electrode, associated with the ion-type sensor is symmetrically located in the detector and displaced from the photoelectric sensor.