Abstract: A wearable display system includes an eyepiece stack having a world side and a user side opposite the world side. During use, a user positioned on the user side views displayed images delivered by the wearable display system via the eyepiece stack which augment the user's field of view of the user's environment. The system also includes an optical attenuator arranged on the world side of the of the eyepiece stack, the optical attenuator having a layer of a birefringent material having a plurality of domains each having a principal optic axis oriented in a corresponding direction different from the direction of other domains. Each domain of the optical attenuator reduces transmission of visible light incident on the optical attenuator for a corresponding different range of angles of incidence.

Abstract: An augmented reality display system. The system can include a first eyepiece waveguide with a first input coupling grating (ICG) region. The first ICG region can receive a set of input beams of light corresponding to an input image having a corresponding field of view (FOV), and can in-couple a first subset of the input beams. The first subset of input beams can correspond to a first sub-portion of the FOV. The system can also include a second eyepiece waveguide with a second ICG region. The second ICG region can receive and in-couple at least a second subset of the input beams. The second subset of the input beams can correspond to a second sub-portion of the FOV. The first and second sub-portions of the FOV can be at least partially different but together include the complete FOV of the input image.

Abstract: A rainbow-free waveguide display, a near-eye display incorporating the rainbow-free waveguide, and methods of manufacturing the rainbow-free waveguide are provided. The display includes a waveguide display configured to direct image light to an eyebox plane having a length (LEyebox) and to a user's eye. The waveguide display includes a waveguide combiner and an out-coupler grating, wherein the out-coupler grating has a grating period ?OC such that all angles of incidence ?in of light from an external light source, result in diffracted angles ?out, that miss the user's eye.

Abstract: Embodiments of the present disclosure describe waveguides having device structures with multiple portions and methods of forming the waveguide having multiportion device structures. The plurality of device structures are formed having two or more portions. The materials of the plurality of portions are chosen such that impedance matching is enabled between the portions to reduce reflection of light from the optical device.

Abstract: Diffraction gratings provide optical elements in head-mounted display systems to, e.g., incouple light into or out-couple light out of a waveguide. These diffraction gratings may be configured to have reduced polarization sensitivity. Such gratings may, for example, incouple or outcouple light of different polarizations with similar level of efficiency. The diffraction gratings and waveguides may include a transmissive layer and a metal layer. The diffraction grating may comprises a blazed grating.

Abstract: Waveguide combiners having a pass-through in-coupler grating are described herein. The waveguide combiners include at least one microdisplay and a stack of at least two waveguide layers. In one configuration of a waveguide combiner described herein, the green FOV and the blue FOV only propagate in a first waveguide and the red FOV only propagates in a second waveguide. In another configuration of a waveguide combiner described herein, the blue FOV, the red FOV, and the green FOV only propagate in the first waveguide, the second waveguide, and a third waveguide respectively. The waveguide combiners including the stack of waveguide layers reduces luminance non-uniformity, color non-uniformity, double-images, and other non-uniformities of the overlayed images from a first microdisplay and, in some embodiments, a second microdisplay.

Abstract: An eyepiece waveguide for an augmented reality display system may include an optically transmissive substrate, an input coupling grating (ICG) region, a multi-directional pupil expander (MPE) region, and an exit pupil expander (EPE) region. The ICG region may receive an input beam of light and couple the input beam into the substrate as a guided beam. The MPE region may include a plurality of diffractive features which exhibit periodicity along at least a first axis of periodicity and a second axis of periodicity. The MPE region may be positioned to receive the guided beam from the ICG region and to diffract it in a plurality of directions to create a plurality of diffracted beams. The EPE region may overlap the MPE region and may out couple one or more of the diffracted beams from the optically transmissive substrate as output beams.

Abstract: Techniques for artifact mitigation in an optical system are disclosed. Light associated with a world object is received at the optical system, which is characterized by a world side and a user side. Light associated with a virtual image is projected onto an eyepiece of the optical system, causing a portion of the light associated with the virtual image to propagate toward the user side and light associated with an artifact image to propagate toward the world side. A dimmer of the optical system positioned between the world side and the eyepiece is adjusted to reduce an intensity of the light associated with the artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer.

Abstract: The present disclosure relates to a metal machining apparatus having a gas nozzle for generating a gas jet. The apparatus also has a nozzle exit opening on one end on the outside; an electronic camera for acquiring a digital image of the end of the gas nozzle with the nozzle exit opening. The apparatus also includes a pattern recognition module for mapping the digital image to at least one nozzle pattern from the group of nozzle state and/or nozzle type.

Abstract: Techniques for artifact mitigation in an optical system are disclosed. Light associated with a world object is received at the optical system, which is characterized by a world side and a user side. Light associated with a virtual image is projected onto an eyepiece of the optical system, causing a portion of the light associated with the virtual image to propagate toward the user side and light associated with an artifact image to propagate toward the world side. A dimmer of the optical system positioned between the world side and the eyepiece is adjusted to reduce an intensity of the light associated with the artifact image impinging on the dimmer and an intensity of the light associated with the world object impinging on the dimmer.

Abstract: An eyepiece waveguide for an augmented reality display system may include an optically transmissive substrate, an input coupling grating (ICG) region, a multi-directional pupil expander (MPE) region, and an exit pupil expander (EPE) region. The ICG region may receive an input beam of light and couple the input beam into the substrate as a guided beam. The MPE region may include a plurality of diffractive features which exhibit periodicity along at least a first axis of periodicity and a second axis of periodicity. The MPE region may be positioned to receive the guided beam from the ICG region and to diffract it in a plurality of directions to create a plurality of diffracted beams. The EPE region may overlap the MPE region and may out couple one or more of the diffracted beams from the optically transmissive substrate as output beams.

Abstract: An anti-reflective waveguide assembly comprising a waveguide substrate having a first index of refraction, a plurality of diffractive optical elements disposed upon a first surface of the waveguide and an anti-reflective coating disposed upon a second surface of the waveguide. The anti-reflective coating preferably increases absorption of light through a surface to which it is applied into the waveguide so that at least 97 percent of the light is transmitted. The anti-reflective coating is composed of four layers of material having different indices of refraction that the first index of refraction and an imaginary refractive index less than 1×10?3 but preferably less than 5×10?4.

Abstract: An eyepiece waveguide for an augmented reality display system. The eyepiece waveguide can include an input coupling grating (ICG) region. The ICG region can couple an input beam into the substrate of the eyepiece waveguide as a guided beam. A first combined pupil expander-extractor (CPE) grating region can be formed on or in a surface of the substrate. The first CPE grating region can receive the guided beam, create a first plurality of diffracted beams at a plurality of distributed locations, and out-couple a first plurality of output beams. The eyepiece waveguide can also include a second CPE grating region formed on or in the opposite surface of the substrate. The second CPE grating region can receive the guided beam, create a second plurality of diffracted beams at a plurality of distributed locations, and out-couple a second plurality of output beams.

Abstract: Waveguides comprising materials with refractive index greater than or equal to 1.8 and methods of patterning waveguides are disclosed. Patterned waveguides comprising materials with refractive index greater than or equal to 1.8 can be incorporated in display devices, such as, for example wearable display devices to project virtual images to a viewer.

Abstract: An anti-reflective waveguide assembly comprising a waveguide substrate having a first index of refraction, a plurality of diffractive optical elements disposed upon a first surface of the waveguide and an anti-reflective coating disposed upon a second surface of the waveguide. The anti-reflective coating preferably increases absorption of light through a surface to which it is applied into the waveguide so that at least 97 percent of the light is transmitted. The anti-reflective coating is composed of four layers of material having different indices of refraction that the first index of refraction and an imaginary refractive index less than 1×10?3 but preferably less than 5×10?4.

Abstract: The present disclosure relates to a metal machining apparatus having a gas nozzle for generating a gas jet. The apparatus also has a nozzle exit opening on one end on the outside; an electronic camera for acquiring a digital image of the end of the gas nozzle with the nozzle exit opening. The apparatus also includes a pattern recognition module for mapping the digital image to at least one nozzle pattern from the group of nozzle state and/or nozzle type.

Abstract: An eyepiece waveguide for an augmented reality display system. The eyepiece waveguide can include an input coupling grating (ICG) region. The ICG region can couple an input beam into the substrate of the eyepiece waveguide as a guided beam. A first combined pupil expander-extractor (CPE) grating region can be formed on or in a surface of the substrate. The first CPE grating region can receive the guided beam, create a first plurality of diffracted beams at a plurality of distributed locations, and out-couple a first plurality of output beams. The eyepiece waveguide can also include a second CPE grating region formed on or in the opposite surface of the substrate. The second CPE grating region can receive the guided beam, create a second plurality of diffracted beams at a plurality of distributed locations, and out-couple a second plurality of output beams.

Abstract: Disclosed are techniques for improving the color uniformity of a display of a display device. A plurality of images of the display are captured using an image capture device. The plurality of images are captured in a color space, with each image corresponding to one of a plurality of color channels. A global white balance is performed to the plurality of images to obtain a plurality of normalized images. A local white balance is performed to the plurality of normalized images to obtain a plurality of correction matrices. Performing the local white balance includes defining a set of weighting factors based on a figure of merit and computing a plurality of weighted images based on the plurality of normalized images and the set of weighting factors. The plurality of correction matrices are computed based on the plurality of weighted images.

Abstract: A method for displaying an image using a wearable display system including directing display light from a display towards a user through an eyepiece to project images in the user's field of view, determining a relative location between an ambient light source and the eyepiece, and adjusting an attenuation of ambient light from the ambient light source through the eyepiece depending on the relative location between the ambient light source and the eyepiece.

Abstract: A pupil separation system includes an input surface, a central portion including a set of dichroic mirrors, a first reflective surface disposed laterally with respect to the central portion, and a second reflective surface disposed laterally with respect to the central portion. The pupil separation system also includes an exit face including a central surface operable to transmit light in a first wavelength range, a first peripheral surface adjacent the central surface and operable to transmit light in a second wavelength range, and a second peripheral surface adjacent the central surface and opposite to the first peripheral surface. The second peripheral surface is operable to transmit light in a third wavelength range.