Wafer-Scale, Quasi-Random Thin-film Filters for Reconstructive Spectrometer Applications

Abstract

The miniaturization of the spectrometer is essential for commercial applications. The reconstructive spectrometer is less affected by the relationship between size and resolution than conventional spectrometers. The photonic structure (i.e., nanowire, and thin film filter) of reconstructive spectrometer act as response function, and restore the original signal by solving the linear equation. However, it is difficult to commercialize due to complex fabrications and challenges to mass production. In this study, we provide simple wafer-scale fabrication method by adopting multi-stack linear variable deposition.The proposed reconstruction spectrometer restores the original optical signal with relatively good accuracy and a low mean square error ( 5 ×10−4). The reconstructive spectrometer is compatible with CMOS sensors and can be mass-production due to a small number of fabrication processes, so it is expected to be applied to various fields such as medicine, food, and mobile integration.