| 摘要 |
PROBLEM TO BE SOLVED: To provide a flame detector including a window material configuration accommodating to new gasoline-alternative fuel by expanding a flame detection range.SOLUTION: A flame detector includes: a photodiode (1) for detecting an infrared region; a pyroelectric element (2) for detecting mid-infrared region; and window material structures (11, 12, 14, and 15) provided on front faces of the photodiode and the pyroelectric element. The flame detector, after discriminating the flame from a light source, detects an occurrence of flame on the basis of a comparison between an output of the photodiode and an output of the pyroelectric element with respect to a same detection object. A window material capable of expanding a long-wavelength-side sensitivity area of the pyroelectric element to a wavelength side longer than 4 μm are employed as the window material structures (14 and 15) to be provided on the front face of the pyroelectric element. |
