title: Retroreflective imaging system for optical labeling and detection of microorganisms.
abstract: A retroreflective imaging system for imaging microscopic targets over macroscopic sampling areas is introduced. Detection of microorganism-bound retroreflector (RR) targets across millimeter-scale samples is implemented according to retroreflection directionality, collimation, and contrast design characteristics. Retroreflection directionality is considered for corner-cube (CC) and spherical geometries. Spherical-RRs improve directionality and reliability. Retroreflection collimation is considered for spherical-RRs. Retroreflective images for micro-CC-RRs and micro-spherical-RRs with varying refractive indices show optimal results for high refractive index BaTiO3 micro-spherical-RRs. A differential imaging technique improves retroreflection contrast by 35 dB. High refractive index micro-spherical-RRs and differential imaging, together, can detect microscopic RR targets across macroscopic areas.
authors.forename: Mark H
authors.initials: MH
authors.lastname: Bergen
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Nichols
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Collier
authors.forename: Xian
authors.initials: X
authors.lastname: Jin
authors.forename: Balakrishnan
authors.initials: B
authors.lastname: Raja
authors.forename: Deborah J
authors.initials: DJ
authors.lastname: Roberts
authors.forename: Paul
authors.initials: P
authors.lastname: Ruchhoeft
authors.forename: Richard C
authors.initials: RC
authors.lastname: Willson
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Holzman