High-resolution thin "guest-host" micropolarizer arrays for visible imaging polarimetry

We report a micropolarizer array technology exploiting "guest-host" interactions in liquid crystals for visible imaging polarimetry. We demonstrate high resolution thin micropolarizer arrays with a 5 μm×5 μm pixel pitch and a thickness of 0.95 μm. With the "host" nematic liquid crystal molecules photo-aligned by sulfonic azo-dye SD1, we report averaged major principal transmittance, polarization efficiency and order parameter of 80.3%, 0.863 and 0.848, respectively across the 400 nm-700 nm visible spectrum range. The proposed fabrication technology completely removes the need for any selective etching during the fabrication/integration process of the micropolarizer array. Fully CMOS compatible, it is simple and cost-effective, requiring only spin-coating followed by a single ultraviolet-exposure through a "photoalignment master". This makes it well suited to low cost polarization imaging applications.