Abstract: A method for determining the voltage sensitivity of the distance between the mirrors of a Fabry-Perot interferometer in a measuring device, which is intended to measure a predefined gas (CO2), of which at least one absorption maximum or minimum is known. At least two calibration point are defined device specifically using a reference gas (N2) in controlled conditions. A ‘virtual’ signal-control-voltage sensitivity curve, is formed with the aid of the calibration points formed using the reference gas (N2), ratios of the measurement points of the predefined gas (CO2) and of the corresponding values of the reference-gas curve are formed, and at least one voltage value corresponding to the minimum or maximum is defined from the ratios, in which case, on the basis of the wavelengths of the absorption minima or maxima of the gases (CO2, N2) being measured, the voltage sensitivity of the distance between the mirrors can be defined unequivocally.

Abstract: This publication discloses a method for determining the voltage sensitivity of the distance between the mirrors of a Fabry-Perot interferometer in a measuring device, which is intended to measure a predefined gas (e.g., CO2), of which at least one absorption maximum (ABS) or minimum is known. According to the method, at least two calibration point are defined device specifically using a reference gas (N2) in controlled conditions, in such a way that at least one of the calibration points (ABS) includes information on the control-voltage-signal-pair for one absorption maximum (ABS) of the gas being measured, and the other a corresponding pair for the reference measurement (REF), and the signal-control-voltage sensitivity is determined for the predefined gas (e.g., CO2). According to the invention, a “virtual” signal-control-voltage sensitivity curve, for example, a straight line, is formed with the aid of the calibration points formed using the reference gas (e.g.