Flame sensor

摘要

A flame sensor according to the invention enables automatic monitoring and/or control of the condition of combustion of a flame such as perfect combustion or imperfect combustion by detection of particular infra-red radiations emitted by the flame. The flame sensor includes a rotary disc having two sets of band-pass filters mounted thereon, a single photoelectric conversion device for measuring intensity of radiations having passed said band-pass filters and a division circuit for providing a ratio of an output of the photoelectric conversion device containing the wavelength of a resonant radiation of a carbon dioxide to an output of the photoelectric conversion device containing no such wavelength.