High Performance Infrared Gas Measurement System Based on a Semiconductor Gas Sensor IR Source with Tunable Fabry-Pérot Filter

摘要

In this work, a miniature infrared (IR) spectrometer for gas analysis was realized by using arnmicrostructured Fabry-Pérot interferometer as a tunable filter. Two of these filters were applied for tworndifferent wavelength ranges (3.9 to 5.0 μm and 8 to 10.5 μm, respectively). Thus, a wide range ofrngases can be detected and quantified. A semiconductor gas sensor was used as IR radiation source.rnWith filter modulation frequencies of several Hz, optical spectra can be recorded quickly and severalrngases can be monitored simultaneously. Furthermore, a computer model of the system was createdrnwhich describes all the steps of the measurement chain and calculates the influences on the measurementrnat each step. To generate the models of the Fabry-Pérot filters (FPF), for example, the devicesrnwere characterized using Fourier Transform Infrared (FTIR) spectroscopy. Gas measurements werernperformed in the two wavelength ranges to demonstrate the functionality of the system’s operatingrnmode as a low cost spectrometer.