CAREER: Ultra-compact High-speed Infrared Polarimetric Spectroscopic (IRPS) Imaging system

Arizona State University, Scottsdale AZ

Investigators

Abstract

Polarization, similar to intensity and wavelength, contains important information of light. Polarimetric imaging provides quantitative measurements of the polarization state at individual pixels while spectrometers capture the intensity information at each specific wavelength of light. Infrared polarimetric spectroscopic imaging technique combines the advantages of both infrared spectroscopy and polarimetric imaging. It not only enables chemical mapping of objects, but can also provide spatial information of molecular structure, morphology, homogeneity and surface conditions, which are essential for chemical analysis, biomedical imaging, cancer diagnosis, space and industrial applications. Existing Infrared polarimetric spectroscopic imaging system often suffer from bulky physical size, long image collection time, low spatial resolution and limited operation wavelength range. The objective of this CAREER project is to design and implement compact broadband high speed infrared polarimetric spectroscopic imaging systems. The proposed systems are compact, fast, broadband and have the potential to provide complete and accurate measurements with high spatial and frequency resolution. They can become powerful enabling tools for medical researchers, doctors and others. Such systems can potentially also be adopted in industries for material analysis and process monitoring. The education and outreach program of this CAREER project will promote multidisciplinary research involving nanotechnology, optical imaging, infrared spectroscopy and biomedical engineering by involving undergraduate and high school students in research activities. A group of 5-6th grade students will be introduced to optic engineering in an online/hybrid program developed by the PI and a course on metasurfaces and metamaterials and their applications will be developed. The research outcomes will be disseminated to the public, industry, medical researchers, doctors and other application experts to increase public awareness, collect feedback and seek opportunities to move the technology toward practical applications. This project is aimed to design and implement ultra-compact infrared polarimetric spectroscopic imaging systems with broadband wavelength coverage and fast imaging collection speed. The focus is to demonstrate and integrate metasurface-based polarization state generator and analyzer with broadband mid-infrared source and imaging sensor to improve the system compactness, imaging collection speed and measurement accuracy. The proposed polarization state generator and analyzer devices will be investigated and implemented by exploiting unique properties of high speed tunable metasurfaces. Theoretical and experimental analyses will be carried out to study the performance of the proposed system and explore the fundamental limitations of imaging speed, measurement accuracy, spatial and spectral resolution. The impacts of device and system imperfections, such as fabrication deviations, noise, alignment error, will also be investigated. Infrared polarimetric spectroscopic imaging measurements of thin films and other samples will be performed with prototype systems to explore the advantages and limitations of the proposed system in practical applications for future guidance on device and system improvement. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.