Abstract: There is disclosed a waveguide for use in an augmented reality or virtual reality display. The waveguide comprises a plurality of optical structures in a photonic crystal. The plurality of optical structures are arranged in an array to provide at least two diffractive optical elements. Each of the two diffractive optical elements is configured to receive light from an input direction and couple it towards the other diffractive optical element which can then act as an output diffractive optical element, providing outcoupled orders towards a viewer. The plurality of optical structures respectively have a shape, when viewed in the plane of the waveguide, comprising twelve substantially straight sides, six of the sides having respective normal vectors at a first angle, and the other six of the sides having respective normal vectors at a second angle which is different to the first angle.

Abstract: An optical device for an augmented reality or virtual reality display. A first input diffractive optical element is arranged on a waveguide to receive light from a projector, couple a first portion of the light into the waveguide along a first path, and allow a second portion of the light to pass through. A second input diffractive optical element is arranged to receive the second portion of the light and couple a third portion of the received light along a second path. An output diffractive optical element receives light along the first and second paths and couples the received light out of the waveguide towards a viewer at a first pattern of positions for light along the first path and at a second pattern of positions for light along the second path, providing a first and second plurality of exit pupils corresponding to the first and second pattern of positions.

Abstract: An optical waveguide combiner includes an optical waveguide substrate and an optical input region. The optical input region includes an optical input diffractive grating integrated in, or disposed on, the optical waveguide substrate. An optical output region includes an optical output diffractive grating integrated in, or disposed on, the optical waveguide substrate, At least one non-diffractive region includes at least one optical non-diffractive array of nanostructures, wherein said at least one optical non-diffractive array of nanostructures is integrated in, or disposed on, the object side of said optical waveguide substrate and at least partially surrounds at least said optical output grating; wherein the external visible reflectance of said at least one non-diffractive array of nanostructures is substantially equal to the external visible reflectance of said optical output grating.

Abstract: There is disclosed a waveguide for use in an augmented reality or virtual reality display. The waveguide comprises a plurality of optical structures in a photonic crystal. The plurality of optical structures are arranged in an array to provide at least two diffractive optical elements. Each of the two diffractive optical elements is configured to receive light from an input direction and couple it towards the other diffractive optical element which can then act as an output diffractive optical element, providing outcoupled orders towards a viewer. The plurality of optical structures respectively have a shape, when viewed in the plane of the waveguide, comprising twelve substantially straight sides, six of the sides having respective normal vectors at a first angle, and the other six of the sides having respective normal vectors at a second angle which is different to the first angle.

Abstract: An optical structure is disclosed for use in an augmented reality display. The structure includes a waveguide (52) and an input diffractive optical structure (54) configured to receive light from a projector and couple the received light into the waveguide (52). An output diffractive optical structure (60) is configured to receive light from the input diffractive optical element (54) in an input direction, wherein the output diffractive optical structure comprises at least a first diffractive optical element (30) and a second diffractive optical element (32) with different respective diffraction efficiencies, wherein the first diffractive optical element has a relatively high diffraction efficiency and the second diffractive optical element has a relatively low diffraction efficiency and the first and second diffractive optical elements are overlaid on one another in or on the waveguide. The output diffractive optical structure (60) comprises a first portion (62) and a second portion (64).