Spectral Discrimination Sensors Based on Nanomaterials and Nanostructures: A Review

Imaging sensors as a critical technology are greatly significant in numerous light detection applications including security monitor, smart mobile devices, machine vision, navigation, self-driving, drones and remote sensing etc. In particular, spectral imaging technology such as multispectral and hyperspectral imaging are attracting more and more attention due to the available spectral and spatial information, which provide an opportunity for deeper cognition of the detected object. However, conventional strategy for wavelength sensing by complicated optical system has obstacle in achieving lightweight, low cost, high quality image and high pixel densities. Therefore, new emerging strategies based on the nanomaterials and nanostructures involving filter-assisted and filter-free light detection are explored to achieve precise spectral discrimination. Here, we review the latest advances of these emerging approaches for spectral discrimination. Furthermore, every filter-assisted and filter-free strategy was discussed and compared in detail by analyzing their fundamental physical principles.