SBIR Phase I: Electro-optic liquid crystal microspectrometers as rapid and inexpensive optical sensors.

This Small Business Innovation Research phase I project will utilize contemporary electro-optic (EO) device principles (based on unique liquid crystal materials and configurations) to develop a fully functional chip-scale spectrometer and hyperspectral imaging device. Liquid crystal materials can be used to create analog electro-optically tunable reflective or transmissive filters with narrow optical bandgaps (< 20nm) which, when coupled with a photodetector or array detector, creates a two component non-dispersive spectrometer or hyperspectral imager, respectively. This mode of operation is markedly different than that required in display technology, where liquid crystals are using as digital light valves with color filters. The proposed spectrometer with its fabrication method eliminates the need for expensive gratings or focal plane arrays, enabling fabrication of ultra-compact and inexpensive microchip spectrometers (< 1 cm3 size scale). If successful the manufacturing of this device will have an impact in cost or space-sensitive applications that only require lower resolution spectral scanning. The PI and the team will utilize liquid crystal micro-spectrometer technology as the chief component in its core technology in identifying anemia noninvasively using reflectance spectra from blood vessels lining the inner surface of the eyelid (conjunctiva). Compact optical spectrometers, as the one proposed in this work, have applicability in numerous fields within and beyond medical devices, including on-line screening tools in manufacturing, active elements in fluorescence microscopy, and wavelength selective devices in telecommunications. Explorations of these types of devices will not only enhance the knowledgebase in liquid crystals beyond display technologies, but also drive spectroscopy into fields where instrumentation had previously been restrictive.