Dye and pigment-free structural colors and angle-insensitive spectrum filters

摘要

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.

主权项

1. A transmission-type angle insensitive optical spectrum filtering device comprising:
a localized plasmonic nanoresonator assembly comprising a multi-layered metal material layer comprising a metal layer sandwiched between two highly reflective metal layers, wherein the metal layer defines at least one nanogroove and a dielectric material disposed within the at least one nanogroove and disposed adjacent to one of the two highly reflective metal layers, wherein 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 transmit a filtered output having a predetermined range of wavelengths that displays angle insensitivity so that the predetermined range of wavelengths varies less than or equal to about 20 nm from an incidence angle of 0° to an incidence angle of 90° with respect to the filtering device.