Abstract: The present invention is a programmable and latching retro-reflective construct suitable for use as an optical label in an optical labeling system. The invention contains retro-reflective structures such as lens beads, corner cubes or other retro-reflecting type structures. The retro-reflective construct further comprises a wavelength selective, programmable and latching reflecting structure located at the reflecting surfaces of the retro-reflective structures. The optical construct can optionally contain additional optical filtering structures. Methods for fabricating the invention are also described.

Abstract: The present invention is a programmable and latching retro-reflective construct suitable for use as an optical label in an optical labeling system. The invention contains retro-reflective structures such as lens beads, corner cubes or other retro-reflecting type structures. The retro-reflective construct further comprises a wavelength selective, programmable and latching reflecting structure located at the reflecting surfaces of the retro-reflective structures. The optical construct can optionally contain additional optical filtering structures. Methods for fabricating the invention are also described.

Abstract: The present invention is a programmable and latching retro-reflective construct suitable for use as an optical label in an optical labeling system. The invention contains retro-reflective structures such as lens beads, corner cubes or other retro-reflecting type structures. The retro-reflective construct further comprises a wavelength selective, programmable and latching reflecting structure located at the reflecting surfaces of the retro-reflective structures. The optical construct can optionally contain additional optical filtering structures. Methods for fabricating the invention are also described.

Abstract: Exemplary embodiments of a structured surface are described which can efficiently reflect, steer or focus incident electromagnetic radiation. The surface impedance may be adjustable and can impart a phase shift to the incident wave using tunable electrical components of the surface. An array of electrodes interconnected by variable capacitors may be used for beam steering and phase modulation. In an exemplary embodiment, the electrodes have a circular configuration.

Abstract: A method for designing artificial impedance surfaces is disclosed. The method involves matching impedance component values required for a given far-field radiation pattern (determined, for example, by holographic means) with measured or simulated impedance component values for the units of a lattice of conductive structures used to create an artificial impedance surface, where the units of the lattice have varied geometry. For example, a unit could be a square conductive structure with a slice (removed or missing material) through it. The measured or simulated impedance components are determined by measuring wavevector values for test surfaces in three or more directions over any number of test surfaces, where each unit of a given test surface has the same geometric shape and proportions as all of the other units of that test surface, but each test surface has some form of variation in the unit geometry from the other test surfaces. These test measurements create a table of geometry vs.

Abstract: The presently disclosed invention provides for the fabrication of porous anodic alumina (PAA) films on a wide variety of substrates. The substrate comprises a wafer layer and may further include an adhesion layer deposited on the wafer layer. An anodic alumina template is formed on the substrate. When a rigid substrate such as Si is used, the resulting anodic alumina film is more tractable, easily grown on extensive areas in a uniform manner, and manipulated without danger of cracking. The substrate can be manipulated to obtain free-standing alumina templates of high optical quality and substantially flat surfaces. PAA films can also be grown this way on patterned and non-planar surfaces. Furthermore, under certain conditions, the resulting PAA is missing the barrier layer (partially or completely) and the bottom of the pores can be readily accessed electrically.

Abstract: Exemplary embodiments of a structured surface are described which can efficiently reflect, steer or focus incident electromagnetic radiation. The surface impedance may be adjustable and can impart a phase shift to the incident wave using tunable electrical components of the surface. An array of electrodes interconnected by variable capacitors may be used for beam steering and phase modulation. In an exemplary embodiment, the electrodes have a circular configuration.

Abstract: A digitally controlled tunable impedance surface. The tunable impedance surface is of the type having a two dimensional array of conducting plates disposed adjacent a dielectric medium; a ground plane spaced from the two dimensional array of conducting plates, the dielectric medium occurring at least between and separating the two dimensional array of conducting plates and the ground plane; and conductors coupling alternating ones of the conducting plates to the ground plane. A plurality of voltage controlled capacitors are coupled between adjacent plates in the two dimensional array of conducting plates and an array of digital to analog converters are disposed preferably on or near the ground plane. Each digital to analog converter has analog output voltage pads coupled to selected ones of adjacent conducting plates and has at least a digital input for receiving digital words representing at least in part analog voltages to be applied to the selected ones of the adjacent conducting plates.

Abstract: The presently disclosed invention provides for the fabrication of porous anodic alumina (PAA) films on a wide variety of substrates. The substrate comprises a wafer layer and may further include an adhesion layer deposited on the wafer layer. An anodic alumina template is formed on the substrate. When a rigid substrate such as Si is used, the resulting anodic alumina film is more tractable, easily grown on extensive areas in a uniform manner, and manipulated without danger of cracking. The substrate can be manipulated to obtain free-standing alumina templates of high optical quality and substantially flat surfaces. PAA films can also be grown this way on patterned and non-planar surfaces. Furthermore, under certain conditions the resulting PAA is missing the barrier layer (partially or completely) and the bottom of the pores can be readily accessed electrically.

Abstract: The presently disclosed invention provides for the fabrication of porous anodic alumina (PAA) films on a wide variety of substrates. The substrate comprises a wafer layer and may further include an adhesion layer deposited on the wafer layer. An anodic alumina template is formed on the substrate. When a rigid substrate such as Si is used, the resulting anodic alumina film is more tractable, easily grown on extensive areas in a uniform manner, and manipulated without danger of cracking. The substrate can be manipulated to obtain free-standing alumina templates of high optical quality and substantially flat surfaces PAA films can also be grown this way on patterned and non-planar surfaces. Furthermore, under certain conditions the resulting PAA is missing the barrier layer (partially or completely) and the bottom of the pores can be readily accessed electrically.