Imaging polarimetry is an essential diagnostic tool in astronomy and solar physics. Standard instruments, other than being generally expensive, complex and/or with moving parts (all of which are problematic features for space applications), provide measurements of the components of the polarized light sampled at different points of time and/or space (depending on the scheme adopted), thus introducing artefacts difficult to eliminate, especially when the subjects are moving or the illumination is variable.
Development of compact on-chip polarization sensitive detectors is therefore of great interest and, recently, polarimetric image sensors based on a pattern of wire-grid polarizers directly deposited on chip have been introduced in the market. In order to obtain compact imaging detectors able to simultaneously detect the polarization state of the light at each pixel, to minimize and control the systematic errors of the polarimetric measures, we investigated a different approach based on the use of organic conjugated systems possessing both high extinction coefficients and emi ssion efficiencies in selected bands, combined with intrinsic anisotropy originating from the 1D molecular structure, which makes them intrinsically sensitive to the polarization of the incoming light.
As a proof of concept, we developed films able to convert the polarization components of the incoming light into different colors, and coupled them to standard color image sensor. Preliminary tests with commercial color cameras are described.