IR gas analyser for multi-atomic, non-elementary gas - corrects for variations in intensities of different wavelengths with variations source temp. variation

摘要

The analyser contains an absorption cuvette for the gas to be analysed, two interference filters, a radiation receiver for measuring absorption in the measurement gas, a radiation receiver producing a reference signal and an evaluation circuit consisting of a quotient surface. The receiver (14,15) signals are corrected, after processing in amplifiers (16,17), rectifiers (22,23) and low-pass filters (24,25), using a signal representing the state of the radiation source, an amplifier (4) and at least one correction circuit (26,28) in conjunction with the quotient circuit (27). The correction results in a constant quotient of the corrected signal when there is no gas and as the ambient temp. varies. ADVANTAGE - Continuous measurement.