A Compact, Low Power Device Using Mie Resonance for Multispectral Polarization Image Detection

The changing global nuclear security landscape requires new imaging tools for remote detection applications. Integrating multiple imaging applications into one sensor has that advantage of reducing unmanned aerial vehicle payloads which can result in enhanced, streamlined data collection with fewer flights. While gathering different optical field signatures such as intensity, wavelength, and polarization can provide a detailed understanding of objects and activities in a scene, combing different physical measurement techniques is fraught with design tradeoffs. Different aspects of image quality (e.g., information about incident photons’ spatial coordinates, intensity, wavelength, time, and polarization) need to be balanced with weight, size and ability to withstand environmental damage as well as the need for efficient data transmission and the ability to make sense of the huge amounts of information collected. This proposal utilizes wavelength- and subwavelength-sized Mie photo sensor pixels to integrate multiple, high resolution, imaging modalities into a single, compact and low power snapshot imaging device that exceeds the performance of current systems and enables improved system footprint size/weight/power (SWaP) metrics. The Mie photo sensor characteristics allow for new and powerful array designs which can be used to create novel multimodal imaging systems tailored to the specific imaging application. Importantly, with the dramatically improved structure and device physics of the photo sensing element, more visual data (e.g., spectral, polarimetric) can be collected within an imaging array without increasing the size of the focal plane array. Phase I demonstrated that different shaped pixels have unique, complex response patterns to different wavelengths and polarizations. Substantial portions of the fabrication process have been developed with multiple portions of these processes integrated into a continuous flow. The process has been slow and methodical, supporting the feasibility of fabricating Mie photo sensors with the desired dimension control for demonstrating wavelength and polarization selectivity. The goals of the Phase II project are to demonstrate target wavelength and polarization selectivity employing clusters of complementary sensors; develop a fabrication process for low-volume production of imaging pixels that are on the same scale of visible light’s wavelength or smaller and complete a comprehensive sensor and array response characterization. This novel imaging system would play an important role in the detection and characterization of global nuclear security threats, cross-cutting functions and foundational capabilities across nonproliferation, counterterrorism, and emergency response mission areas, enabling effective emergency response, advanced safeguards, efficient treaty verification, and other government applications. It also has important commercial remote sensing applications including precision agriculture, security, and land management.