RESUMEN
We present the experimental demonstration of what are to our knowledge the first two-dimensional planar plasmonic lenses formed by an array of spatially varying cross-shaped apertures in a metallic film for Fresnel-region focusing. The design utilizes localized surface plasmon resonances occurring inside the apertures, accompanied by an aperture geometry dependent phase shift, to achieve the desired spatial phase modulation in the transmitted field. The performance of lenses with different design configurations was evaluated using a confocal scanning optical microscope, and the effects of diffraction on the optical response of these microscale devices are discussed.
Asunto(s)
Lentes , Nanotecnología/instrumentación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
A novel application of quantitative phase imaging under linearly polarized light is introduced for studying unstained anisotropic live cells. The method is first validated as a technique for mapping the two-dimensional retardation distribution of a well-characterized optical fiber and is then applied to the characterization of unstained isolated cardiac cells. The experimental retardation measurements are in very good agreement with the established Brace-Köhler method, and additionally provide spatially resolved cell birefringence and phase data.