Chirality Sensor using an Electro-Optic-Polymer Circular-Polarization Modulator

Conventional optical waveguide modulators failed to provide modulated output of circularly polarized light. In this program, Radiant Research, Inc. (RRI) proposes a miniaturized circular-polarization modulator (CPM) that operates at arbitrary modulationrates up to 100 GHz and at various optical wavelengths from 700 to 1600 nm. Specifically, the CPM will take the output of a laser diode and produce a free-space laser beam that alternates in time between left- and right-hand-circular states ofpolarization, without any moving parts. For BMDO, the CPM provides a source of polarization modulated light for remote sensing, scanned object detection in fog, and imaging polarimetry. Innovative is the use of electro-optic (E0) polymer prepared in a veryspecialized manner as developed by RRI. We anticipate that the specifications of the CPM will exceed those of any other compact integrated-optic device capable of controlling dynamically the polarization of a laser beam, which include good output-beamprofile, high-extinction polarization purity, low drive-power consumption, need for only low voltages, and use of only a single high-speed voltage source. The use of EQ polymer provides for mass manufacture at a cost lower than any other technology. Thecompelling nature of our technology has attracted $765,000 in matching funding.Anticipated Benefits/Potential Commercial Applications of the Research or Development. The proposed CPM will make possible new commercial products that are not possible using today's bulky photoelastic, liquid-crystal, and inorganic-crystal polarizationmodulators. The CPM can be used in laser-based polarimeters for detection of chiral molecules. In addition, the CPM can be used in free-space and fiber-based optical communications systems requiring circular-polarization encoding or polarizationscrambling.