Long-wave infrared interferential imaging spectroscopy system based on split-type Sagnac interferometer

Based on split-type Sagnac interferometer, principles of static high-flux interferential imaging spectroscopy were introduced. Equal-ratio depolarizing beam-splitting films working in long-wave infrared were designed and achieved. Design methods of interferometer sizes were given, and interferential light path was verified through TracePro software. By utilizing cryogenic and noncryogenic detectors, the project of infrared interferometer imaging spectrometer was tested with a plastic film transmittance. Measured values from the test turned out to be highly matching with those of high precise Michelson spectrometer, which verified the accuracy of that project. In the end, methods about data rearrangement, baseline correction and apodization were given to preprocess data from push-broom experiment. The results, in turn, verified the feasibility of that systematic working mode.