| Abstract: | Optical spectrum filtering devices displaying minimal angle dependence or
angle insensitivity are provided. The filter comprises a localized
plasmonic nanoresonator assembly having a metal material layer defining
at least one nanogroove and a dielectric material disposed adjacent to
the metal material layer. The dielectric material is disposed within the
nanogroove(s). The localized plasmonic nanoresonator assembly is
configured to funnel and absorb a portion of an electromagnetic spectrum
in the at least one nanogroove via localized plasmonic resonance to
generate a filtered output having a predetermined range of wavelengths
that displays angle insensitivity. Thus, flexible, high efficiency angle
independent color filters having very small diffraction limits are
provided that are particularly suitable for use as pixels for various
display devices or for use in anti-counterfeiting and cryptography
applications. The structures can also be used for colored print
applications and the elements can be rendered as pigment-like particles. |