A broadly tunable surface plasmon coupled wavelength filter for visible and near infrared hyperspectral imaging

A BROADLY TUNABLE SURFACE PLASMON-COUPLED WAVELENGTH FILTER FOR VISIBLE AND NEAR INFRARED HYPERSPECTRAL IMAGING AJAYKUMAR ZALAVADIA Bachelor of Pharmacy Rajiv Gandhi University of Health Sciences 2007 Master of Science in Analytical Chemistry Governors State University 2009 Submitted in partial fulfillment of the requirements for the degree DOCTOR OF PHILOSOPHY IN CLINICAL AND BIOANALYTICAL CHEMISTRY at the CLEVELAND STATE UNIVERSITY May 2018 We hereby approve this dissertation for Ajaykumar H Zalavadia, Candidate for the Doctor of Philosophy in Clinical-Bioanalytical Chemistry degree for the Department of Chemistry and Cleveland State University’s College of Graduate Studies Date: Dr John F Turner II, Department of Chemistry ( Dissertation Committee Chairperson ) Date: Dr David W Ball, Department of Chemistry ( Dissertation Committee Member ) Date: Dr Mekki Bayachou, Department of Chemistry ( Dissertation Committee Member ) Date: Dr Baochuan Guo, Department of Chemistry ( Dissertation Committee Member ) Date: Dr Petru S Fodor, Department of Physics ( Dissertation Committee Member ) Date of Defense: March 8th, 2018 Dedicated to Bansari… ACKNOWLEDGEMENT I am eternally grateful to my advisor Dr John F Turner, II for his invaluable guidance since 2010, neither a thank you, nor this acknowledgement is enough to gratify your contribution in making the person I am today I will try my very best to not let you down ever I would like to thank Dr Petru S Fodor, for giving me the opportunity to serve as a graduate assistant for the scanning electron microscopy facility, through which I also have received financial support during my dissertation research work I would like to express my gratitude to my committee members Dr David Ball, Dr Mekki Bayachou, Dr Baochuan Guo, and Dr Taysir Nayfeh for their suggestions about my research during my candidacy and annual reports I would also like to thank the Department of Chemistry for providing me the opportunity to be a teaching assistant to advance my teaching skills, the College of Sciences for awarding me the Doctoral Dissertation Research Award for 2014 and the Cleveland State University’s college of graduate studies for giving me the opportunity to advance my career and pursue a doctorate degree Dear Mom, Dad and Bansari, I will be forever in debt for your unconditional love during the good and the bad times of my life and never giving up on me, without your emotional and financial support I would not have been able to pursue my dreams I am thankful to my friends and colleagues for all the productive, and non-productive but fun; time spent together on campus or off campus You know who you are without being named individually A BROADLY TUNABLE SURFACE PLASMON-COUPLED WAVELENGTH FILTER FOR VISIBLE AND NEAR INFRARED HYPERSPECTRAL IMAGING AJAYKUMAR ZALAVADIA ABSTRACT Hyperspectral imaging is a set of techniques that has contributed to the study of advanced materials, pharmaceuticals, semiconductors, ceramics, polymers, biological specimens, and geological samples Its use for remote sensing has advanced our understanding of agriculture, forestry, the Earth, environmental science, and the universe The development of ultra-compact handheld hyperspectral imagers has been impeded by the scarcity of small widefield tunable wavelength filters The widefield modality is preferred for handheld imaging applications in which image registration can be performed to counter scene shift caused by irregular user motions that would thwart scanning approaches In the work presented here an electronically tunable widefield wavelength filter has been developed for hyperspectral imaging applications in the visible and near-infrared region Conventional electronically tunable widefield imaging filter technologies include liquid crystal-based filters, acousto-optic tunable filters, and v electronically tuned etalons; each having its own set of advantages and disadvantages The construction of tunable filters is often complex and requires elaborate optical assemblies and electronic control circuits I introduce in the work presented here is a novel widefield tunable filter, the surface plasmon coupled tunable filter (SPCTF), for visible and near infrared imaging The SPCTF is based on surface plasmon coupling and has simple optical design that can be miniaturized without sacrificing performance The SPCTF provides diffraction limited spatial resolution with a moderately narrow nominal passband (