Error analysis and spectral reconstruction of an infrared static miniature interferometric spectrometer

Scientific-grade spectrometers with high hyperspectral resolution and high spectral accuracy are desirable in miniaturized optical systems to maintain stable and real-time spectral sampling. Fourier transform spectrometers that utilize high-precision moving mirrors generally struggle to enhance their miniaturization and stable real-time performance. A static infrared spectral measurement method is proposed that uses micro/nano-optical devices as the core of static interference and lightweight imaging. The use of micro/nano step mirrors allows for the instantaneous sampling of spectra. By employing an array of micro/nano lenses, interference imaging for each spectral channel can be accomplished. The spectrometer's all-static micro/nano-optical structure results in a reduction in volume and weight of more than half. Enhanced precision in design and fabrication is achieved through optical error analysis via a full-linkage optical field transmission model. An image edge detection-assisted spectral inversion algorithm is proposed, and the sampling stability and reconstruction accuracy are verified. The repeatability accuracy of interference intensity sampling surpasses 2%, and the peak accuracy of the reconstructed spectrum exceeds the resolution.