Passive, Active Stokes Polarization Imaging System

The ability for polarization to provide additional information in difficult detection scenarios has strong potential to address a variety of hypervelocity interceptor applications. The targeting of a boost phase missile requires a sensor that can both acquire the target and perform plume / hardbody discrimination. For midcourse scenarios, debris and decoy clouds, low thermal contrast, and target orientation determination can also be measured an active or passive imaging polarimeter. In re-entry phase, an imaging polarization sensor can provide aimpoint selection and orientation determination in the presence of a wake. Imaging polarimeters have the disadvantage of reduced throughput due to the polarizer transmission. When an on-demand polarizer is integrated with appropriate optics, the resulting imaging system becomes a dual-mode imager that has both conventional intensity imaging and imaging polarimeter capabilities. This dual-mode system has the advanced discrimination advantages of the imaging polarimeter while maintaining the throughput advantages of a conventional seeker, thus enabling long detection ranges as well as clutter and decoy rejection for the end game. The marriage of the on-demand polarizer with imaging polarimetry is the key innovation of this SBIR effort and if successful will represent a revolutionary advance in capability for missile seeker technology.