Abstract: An optical device for combining RGB optical signals in a single waveguide. The device includes a plurality of DOEs. A first DOE is configured to receive an optical signal at input propagation angles and to diffract the optical signal based on spectrum such that predominately one spectrum of light is diffracted in a first direction and path and predominately a second spectrum of light is diffracted in a second different direction and path. The first DOE is configured to diffract light into a second DOE. The second DOE is configured to diffract light into a third DOE. The third DOE is configured to diffract light into an eye box keeping output propagation angles substantially parallel to the input propagation angles. A summation of grating vectors for each of the paths is substantially equal to zero.

Abstract: An optical waveguide that performs both in-coupling and out-coupling using two diffractive optical elements is provided. Each optical element is a diffraction grating and can be applied to the same or different surface of the optical waveguide. The diffraction gratings overlap to form two overlapping regions. The first overlapping region in-couples light into the waveguide and the second overlapping region out-couples light from the optical waveguide. Because the optical waveguide only uses two gratings, and therefore only has two grating vectors, the optical waveguide is easier to manufacture than optical waveguides with a greater number of grating vectors.

Abstract: Disclosed are an apparatus and method for providing additional degrees of freedom for diffraction gratings of an output waveguide in a near-eye display device. The near-eye display device includes an imager to generate an image based on light from a light source. The device further includes a waveguide to input a light wave representing the image received from the imager and to output the light wave representing the image toward an optical receptor of a user. The waveguide includes a plurality of diffractive optical elements (DOEs) in a common light path from an input of the waveguide to an output of the waveguide. The DOEs include a plurality of periodic diffraction patterns. Each of the periodic diffraction patterns is represented by a diffraction pattern vector. The periodic diffraction patterns are determined such that a vector summation of the diffraction pattern vectors equals zero.

Abstract: Devices, systems and methods that include specialized waveguide assemblies are provided for performing light transformations. Some waveguide assemblies include a waveguide and a compensating lens. The waveguide includes a front surface and a back surface, wherein the waveguide is configured to receive external light at the front surface and transmit the external light through the waveguide to the back surface. The compensating lens is located on the back surface and is configured to direct light emitted from the back surface toward an exit pupil proximate the back surface. The compensating lens has an input surface oriented toward the waveguide and an opposing output surface oriented away from the waveguide. The waveguide can sometimes increase a user's field of view with minimal distortion on a mixed reality display.

Abstract: An optical waveguide that performs both in-coupling and out-coupling of projected light is provided. The out-coupling region of the waveguide comprises a single-sided or double-sided diffraction grating with at least one of the grating structures conformally coated with a high refractive index material. To reduce the unwanted reflection of light on the waveguide surfaces coated with the high refractive index material, additional antireflective coatings are applied to the diffraction grating areas with the high refractive index coating. The additional antireflective coatings may be very thin to avoid in-coupling, and therefore avoid interference in one or more light rays propagating in the optical waveguide. Alternatively, the antireflective coatings may be very thick to promote in-coupling such that the resulting interference becomes consistent across all light rays propagating in the optical waveguide.

Abstract: A waveguide configured for use with a near-eye display (NED) device can include a light-transmissive substrate configured to propagate light rays through total internal reflection and a diffractive optical element (DOE) on a surface of the substrate that is configured to input and/or output light rays to and/or from the substrate. According to some embodiments the DOE can include a diffraction grating made of first material having a first refractive index and a coating of a second material over the diffraction grating, the second material having a second refractive index that is not equal to the first refractive index.

Abstract: An optical waveguide that performs both in-coupling and out-coupling using two diffractive optical elements is provided. Each optical element is a diffraction grating and can be applied to the same or different surface of the optical waveguide. The diffraction gratings overlap to form two overlapping regions. The first overlapping region in-couples light into the waveguide and the second overlapping region out-couples light from the optical waveguide. Because the optical waveguide only uses two gratings, and therefore only has two grating vectors, the optical waveguide is easier to manufacture than optical waveguides with a greater number of grating vectors.

Abstract: An optical device for combining RGB optical signals in a single waveguide. The device includes a plurality of DOEs. A first DOE is configured to receive an optical signal at input propagation angles and to diffract the optical signal based on spectrum such that predominately one spectrum of light is diffracted in a first direction and path and predominately a second spectrum of light is diffracted in a second different direction and path. The first DOE is configured to diffract light into a second DOE. The second DOE is configured to diffract light into a third DOE. The third DOE is configured to diffract light into an eye box keeping output propagation angles substantially parallel to the input propagation angles. A summation of grating vectors for each of the paths is substantially equal to zero.

Abstract: An optical waveguide that performs both in-coupling and out-coupling using two diffractive optical elements is provided. Each optical element is a diffraction grating and can be applied to the same or different surface of the optical waveguide. The diffraction gratings overlap to form two overlapping regions. The first overlapping region in-couples light into the waveguide and the second overlapping region out-couples light from the optical waveguide. Because the optical waveguide only uses two gratings, and therefore only has two grating vectors, the optical waveguide is easier to manufacture than optical waveguides with a greater number of grating vectors.

Abstract: A waveguide display includes multiple diffractive optical elements (DOEs) that are configured to in-couple image light, provide expanded exit pupil in two directions, and out-couple the image light to a user. An in-coupling DOE is configured to split the full field of view (FOV) of the image light into left and right portions. The left and right FOV portions are respectively propagated laterally in left and right directions in intermediate DOEs which comprise upper and lower portions. The intermediate DOEs provide for exit pupil expansion in a horizontal direction while coupling light to an out-coupling DOE. The out-coupling DOE provides for exit pupil expansion in a vertical direction and out-couples image light with expanded exit pupil for the full FOV. The intermediate DOE portions are configured to steer image light back towards the center of the waveguide to avoid dark areas or stripes in portions of the out-coupling DOE.

Abstract: A diffractive beam expander for use in an augmented-reality display is disclosed. The device can include a optical substrate with a first diffractive optical element having a first diffractive grating disposed on one surface and a second diffractive grating disposed on the opposing surface. Portions of the first and second diffractive gratings overlap to define an in-coupling area configured to receive a beam of incoming light. The first diffractive optical element expands at least part of the received light beam by odd-order diffraction expansion in a first region and a second region and expands at least part of the received light beam by even-order diffraction expansion in a third region. The light components by the first diffractive optical element are then coupled into a second diffractive optical element, which is configured to out-couple at least part of the expanded diffracted light components to exit the substrate by diffraction.

Abstract: Disclosed are an apparatus and method for reducing interference for a near-eye display device. The near-eye display device includes an imager, a spatial light modulator and a waveguide. The imager generates an image based on light from a coherent light source. The spatial light modulator modulates phases of a plurality of coherent light rays representing the image received from the imager. The waveguide receives and guides the light rays having varied phases such that light rays propagating within the waveguide are incoherent with each other.

Abstract: An input-coupler of an optical waveguide includes one or more Bragg polarization gratings for coupling light corresponding to the image in two different directions into the optical waveguide. The input-coupler splits the FOV of the image coupled into the optical waveguide into first and second portions by diffracting a portion of the light corresponding to the image in a first direction toward a first intermediate component, and diffracting a portion of the light corresponding to the image in a second direction toward a second intermediate component. An output-coupler of the waveguide combines the light corresponding to the first and second portions of the FOV, and couples the light corresponding to the combined first and second portions of the FOV out of the optical waveguide so that the light corresponding to the image and the combined first and second portions of the FOV is output from the optical waveguide.

Abstract: Disclosed are an apparatus and method for reducing interference for a near-eye display device. The near-eye display device includes an imager, a spatial light modulator and a waveguide. The imager generates an image based on light from a coherent light source. The spatial light modulator modulates phases of a plurality of coherent light rays representing the image received from the imager. The waveguide receives and guides the light rays having varied phases such that light rays propagating within the waveguide are incoherent with each other.

Abstract: Devices, systems and methods that include specialized waveguide assemblies are provided for performing light transformations. Some waveguide assemblies include a waveguide and a compensating lens. The waveguide includes a front surface and a back surface, wherein the waveguide is configured to receive external light at the front surface and transmit the external light through the waveguide to the back surface. The compensating lens is located on the back surface and is configured to direct light emitted from the back surface toward an exit pupil proximate the back surface. The compensating lens has an input surface oriented toward the waveguide and an opposing output surface oriented away from the waveguide. The waveguide can sometimes increase a user's field of view with minimal distortion on a mixed reality display.

Abstract: Disclosed are an apparatus and method for providing additional degrees of freedom for diffraction gratings of an output waveguide in a near-eye display device. The near-eye display device includes an imager to generate an image based on light from a light source. The device further includes a waveguide to input a light wave representing the image received from the imager and to output the light wave representing the image toward an optical receptor of a user. The waveguide includes a plurality of diffractive optical elements (DOEs) in a common light path from an input of the waveguide to an output of the waveguide. The DOEs include a plurality of periodic diffraction patterns. Each of the periodic diffraction patterns is represented by a diffraction pattern vector. The periodic diffraction patterns are determined such that a vector summation of the diffraction pattern vectors equals zero.

Abstract: A diffractive beam expander for use in an augmented-reality display is disclosed. The device can include a optical substrate with a first diffractive optical element having a first diffractive grating disposed on one surface and a second diffractive grating disposed on the opposing surface. Portions of the first and second diffractive gratings overlap to define an in-coupling area configured to receive a beam of incoming light. The first diffractive optical element expands at least part of the received light beam by odd-order diffraction expansion in a first region and a second region and expands at least part of the received light beam by even-order diffraction expansion in a third region. The light components by the first diffractive optical element are then coupled into a second diffractive optical element, which is configured to out-couple at least part of the expanded diffracted light components to exit the substrate by diffraction.

Abstract: Disclosed are an apparatus and method for reducing ghost image effects and rainbow effects in a near-eye display device. The near-eye display device includes an imager to generate an image based on light from a light source. The near-eye display device further includes at least one planar waveguide. The waveguide inputs light representing the image from the imager at an input surface and outputs the light representing the image toward an optical receptor of a user from an output surface. The waveguide is mounted in an opposite tilt angle. The tilt angle of the waveguide and grating periods of diffraction optical elements of the waveguide serve to reduce ghost image effects and rainbow effects.

Abstract: Lightweight, compact, and cost-efficient solutions for increasing the exit pupil size for use in laser-scanner and waveguide based augmented-reality displays are disclosed. Light from a laser-scanner is focused onto intermediate image plane; a diffuser is positioned at the intermediate image plane to steer light efficiently in a desired direction; the pupil is then expanded with a lens assembly; the lens assembly can contain one or more aspherical and/or free-form optics; the output of the lens assembly can then act as the input to a waveguide plate or stack; and the result is a large field-of-view image with sufficiently large exit pupil to overcome/reduce the pupil-replication problem.

Abstract: A waveguide configured for use with a near-eye display (NED) device can include a light-transmissive substrate configured to propagate light rays through total internal reflection and a diffractive optical element (DOE) on a surface of the substrate that is configured to input and/or output light rays to and/or from the substrate. According to some embodiments the DOE can include a diffraction grating made of first material having a first refractive index and a coating of a second material over the diffraction grating, the second material having a second refractive index that is not equal to the first refractive index.