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Using organic photodetectors for multispectral sensing is attractive due to their unique capabilities to tune spectral response, transmittance, and polarization sensitivity. Existing methods lack tandem multicolor detection and exhibit high spectral cross talk. We exploit the polarization sensitivity of organic photodetectors, together with birefringent optical filters to design single-pixel multispectral detectors that achieve high spectral selectivity and good radiometric performance. Two different architectures are explored and optimized, including the Solc-based and multitwist-retarder-based organic photodetectors. Although the former demonstrated a higher spectral resolution, the latter enables a more compact sensor as well as greater flexibility in device fabrication. 

Simultaneous spectral and polarimetric imaging enables versatile detection and multimodal characterization of targets of interest. Current architectures incorporate a 2×2 pixel arrangement to acquire the full linear polarimetric information causing spatial sampling artifacts. Additionally, they suffer from limited spectral selectivity and high color crosstalk. Here, we demonstrate a bio-inspired spectral and polarization sensor structure based on integrating semitransparent polarization-sensitive organic photovoltaics (P-OPVs) and liquid crystal polymer (LCP) retarders in a tandem configuration. Color tuning is realized by leveraging the dynamic chromatic retardation control of LCP films, while polarization sensitivity is realized by exploiting the flexible anisotropic properties of P-OPVs. The structure is marked by its ultra-thin design and its ability to detect spectral and polarimetric contents along the same optical axis, thereby overcoming the inherent limitations associated with conventional division-of-focal plane sensors.