Interdigitated flame sensor, system and method

Abstract

A flame sensor for combustion flame temperature determination, comprising a first photodiode formed with elongated extending digits, and having a range of optical responsivity within an OH band for producing a first output signal; and a second photodiode formed with for receiving light from a combustion flame and having a range of optical responsivity in a different and overlapping portion of the OH band than the first photodiode device OH band for producing a second output signal; wherein the elongated extensions are positioned with parallel interdigitated longitudinal axis with respect to one another. An optical spectrometer comprises the sensor and a system comprises the sensor. A method for combustion flame temperature determination comprises obtaining a first photodiode signal using a first photodiode device comprising a silicon carbide photodiode with elongated extending digits and having a range of optical responsivity within an OH band; obtaining a second photodiode signal by using a second photodiode device comprising a silicon carbide photodiode with elongated extending digits interdigitated with the elongated extending digits of the first photodiode and a filter, the second photodiode device having a range of optical responsivity in a different and overlapping portion of the OH band than the first photodiode device; and obtaining a ratio using the first and second photodiode signals and using the ratio to determine the combustion flame temperature. A method of fabricating a flame sensor for combustion flame temperature determination, comprises forming a first photodiode with elongated extending digits and having a range of optical responsivity within an OH band for producing a first output signal; forming a second photodiode with elongated extending digits and having a range of optical responsivity in a different and overlapping portion of the OH band than the first photodiode device OH band for producing a second output signal; and positioning the elongated digits of the first photodiode and the second photodiode with parallel interdigitated longitudinal axis with respect to one another.

Dependencies are inferred from the claim text.