Abstract: Three-dimensional grating device includes two (crossed) diffraction gratings, exhibits diffraction efficiency substantially independent of the incident polarization inside an optical communication spectral window from 1.5-1.6 ?m. The gratings are characterized by different periods in two directions, chosen to support only one dispersive diffraction order in addition to the zero-(specular) order. Gratings may be orthogonal. Exemplary grating profiles include but are not limited to sinusoidal and truncated pyramidal (trapezoidal) profiles. A method for diffracting polarization independent light with 90% or higher efficiency. Applications include various wavelength control devices particularly useful in telecommunications.

Abstract: A reflection grating device with a continuous non-reflecting dielectric adjusting layer disposed between a grating structure and one or more continuous reflecting layers is disclosed that operates in an order of interest, such as the 1st order or 3rd order of diffraction, with high efficiency and near-exclusion of unwanted orders. Such devices can be employed, for example, in telecommunication and laser applications.

Abstract: A double-layer grating structure for efficient retroreflection of incident radiation and efficient transmission of the undiffracted incident radiation is disclosed. The grating is constructed of two spaced-apart layers of periodically arranged metal stripes, wherein the stripes in one layer overlap with gaps between the stripes in the second layer. The layers are encapsulated with a dielectric material. A method for producing such grating is also described.

Abstract: Three-dimensional grating device includes two (crossed) diffraction gratings, exhibits diffraction efficiency substantially independent of the incident polarization inside an optical communication spectral window from 1.5-1.6 ?m. The gratings are characterized by different periods in two directions, chosen to support only one dispersive diffraction order in addition to the zero- (specular) order. Gratings may be orthogonal. Exemplary grating profiles include but are not limited to sinusoidal and truncated pyramidal (trapezoidal) profiles. A method for diffracting polarization independent light with 90% or higher efficiency. Applications include various wavelength control devices particularly useful in telecommunications.