Abstract: Augmented reality and virtual reality display systems and devices are configured for efficient use of projected light. In some aspects, a display system includes a light projection system and a head-mounted display configured to project light into an eye of the user to display virtual image content. The head-mounted display includes at least one waveguide comprising a plurality of in-coupling regions each configured to receive, from the light projection system, light corresponding to a portion of the user's field of view and to in-couple the light into the waveguide; and a plurality of out-coupling regions configured to out-couple the light out of the waveguide to display the virtual content, wherein each of the out-coupling regions are configured to receive light from different ones of the in-coupling regions. In some implementations, each in-coupling region has a one-to-one correspondence with a unique corresponding out-coupling region.

Abstract: A virtual image generation system comprises a planar optical waveguide having opposing first and second faces, an in-coupling (IC) element configured for optically coupling a collimated light beam from an image projection assembly into the planar optical waveguide as an in-coupled light beam, a first orthogonal pupil expansion (OPE) element associated with the first face of the planar optical waveguide for splitting the in-coupled light beam into a first set of orthogonal light beamlets, a second orthogonal pupil expansion (OPE) element associated with the second face of the planar optical waveguide for splitting the in-coupled light beam into a second set of orthogonal light beamlets, and an exit pupil expansion (EPE) element associated with the planar optical waveguide for splitting the first and second sets of orthogonal light beamlets into an array of out-coupled light beamlets that exit the planar optical waveguide.

Abstract: A method and system for increasing dynamic digitized wavefront resolution, i.e., the density of output beamlets, can include receiving a single collimated source light beam and producing multiple output beamlets spatially offset when out-coupled from a waveguide. The multiple output beamlets can be obtained by offsetting and replicating a collimated source light beam. Alternatively, the multiple output beamlets can be obtained by using a collimated incoming source light beam having multiple input beams with different wavelengths in the vicinity of the nominal wavelength of a particular color. The collimated incoming source light beam can be in-coupled into the eyepiece designed for the nominal wavelength. The input beams with multiple wavelengths take different paths when they undergo total internal reflection in the waveguide, which produces multiple output beamlets.

Abstract: Architectures are provided for selectively outputting light for forming images, the light having different wavelengths and being outputted with low levels of crosstalk. In some embodiments, light is incoupled into a waveguide and deflected to propagate in different directions, depending on wavelength. The incoupled light then outcoupled by outcoupling optical elements that outcouple light based on the direction of propagation of the light. In some other embodiments, color filters are between a waveguide and outcoupling elements. The color filters limit the wavelengths of light that interact with and are outcoupled by the outcoupling elements. In yet other embodiments, a different waveguide is provided for each range of wavelengths to be outputted. Incoupling optical elements selectively incouple light of the appropriate range of wavelengths into a corresponding waveguide, from which the light is outcoupled.

Abstract: A method of operating an eyepiece waveguide includes directing light from a projector to impinge on an incoupling grating (ICG). The method also includes diffracting a first fraction of the light from the projector into a first portion of the eyepiece waveguide, propagating the first fraction of the light into a second portion of the eyepiece waveguide, and diffracting the first fraction of the light out of the eyepiece waveguide. The method further includes diffracting a second fraction of the light from the projector into the second portion of the eyepiece waveguide, propagating the second fraction of the light into the first portion of the eyepiece waveguide, and diffracting the second fraction out of the eyepiece waveguide.

Abstract: Images perceived to be substantially full color or multi-colored may be formed using component color images that are distributed in unequal numbers across a plurality of depth planes. The distribution of component color images across depth planes may vary based on color. In some embodiments, a display system includes a stack of waveguides that each output light of a particular color, with some colors having fewer numbers of associated waveguides than other colors. The waveguide stack may include multiple pluralities (e.g., first and second pluralities) of waveguides, each configured to produce an image by outputting light corresponding to a particular color. The total number of waveguides in the second plurality of waveguides may be less than the total number of waveguides in the first plurality of waveguides.

Abstract: A wearable display system includes a fiber scanner including an optical fiber and a scanning mechanism configured to scan a tip of the optical fiber along an emission trajectory defining an optical axis. The wearable display system also includes an eyepiece positioned in front of the tip of the optical fiber and including a planar waveguide, an incoupling diffractive optical element (DOE) coupled to the planar waveguide, and an outcoupling DOE coupled to the planar waveguide. The wearable display system further includes a collimating optical element configured to receive light reflected by the incoupling DOE and collimate and reflect light toward the eyepiece.

Abstract: Architectures are provided for selectively outputting light for forming images, the light having different wavelengths and being outputted with low levels of crosstalk. In some embodiments, light is incoupled into a waveguide and deflected to propagate in different directions, depending on wavelength. The incoupled light then outcoupled by outcoupling optical elements that outcouple light based on the direction of propagation of the light. In some other embodiments, color filters are between a waveguide and outcoupling elements. The color filters limit the wavelengths of light that interact with and are outcoupled by the outcoupling elements. In yet other embodiments, a different waveguide is provided for each range of wavelengths to be outputted. Incoupling optical elements selectively incouple light of the appropriate range of wavelengths into a corresponding waveguide, from which the light is outcoupled.

Abstract: Disclosed is an improved diffraction structure for 3D display systems. The improved diffraction structure includes an intermediate layer that resides between a waveguide substrate and a top grating surface. The top grating surface comprises a first material that corresponds to a first refractive index value, the underlayer comprises a second material that corresponds to a second refractive index value, and the substrate comprises a third material that corresponds to a third refractive index value.

Abstract: Images perceived to be substantially full color or multi-colored may be formed using component color images that are distributed in unequal numbers across a plurality of depth planes. The distribution of component color images across depth planes may vary based on color. In some embodiments, a display system includes a stack of waveguides that each output light of a particular color, with some colors having fewer numbers of associated waveguides than other colors. The waveguide stack may include multiple pluralities (e.g., first and second pluralities) of waveguides, each configured to produce an image by outputting light corresponding to a particular color. The total number of waveguides in the second plurality of waveguides may be less than the total number of waveguides in the first plurality of waveguides, and may be more than the total number of waveguides in a third plurality of waveguides, in embodiments that utilize three component colors.

Abstract: An augmented reality system includes a light source configured to generate a virtual light beam. The system also includes a light guiding optical element having an entry portion, an exit portion, and a surface having a diverter disposed adjacent thereto. The light source and the light guiding optical element are configured such that the virtual light beam enters the light guiding optical element through the entry portion, propagates through the light guiding optical element by at least partially reflecting off of the surface, and exits the light guiding optical element through the exit portion. The light guiding optical element is transparent to a first real-world light beam. The diverter is configured to modify a light path of a second real-world light beam at the surface.

Abstract: A display assembly suitable for use with a virtual or augmented reality headset is described and includes the following: an input coupling grating; a scanning mirror configured to rotate about two or more different axes of rotation; an optical element; and optical fibers, each of which have a light emitting end disposed between the input coupling grating and the scanning mirror and oriented such that light emitted from the light emitting end is refracted through at least a portion of the optical element, reflected off the scanning mirror, refracted back through the optical element and into the input coupling grating. The scanning mirror can be built upon a MEMS type architecture.

Abstract: A method of displaying an image to a viewer includes operating a fiber scanning projector to produce a scanned light beam incident on an incoupling diffractive optical element (DOE) coupled to a waveguide. A portion of the light beam is reflected via a reflective back surface of the incoupling DOE. The reflected portion of the scanned light beam is incident on a reflective optical element, which reflects the light beam back to the incoupling DOE. The returning light beam is then diffracted by the incoupling DOE to produce a second pass first diffracted light beam. The second pass first diffracted light beam is propagated within the planar waveguide via total internal reflection (TIR) to an outcoupling DOE, which directs a portion of the second pass first diffracted light beam toward an eye of a viewer to display the image to the user.

Abstract: A method of fabricating a fiber scanning system includes forming a set of piezoelectric elements. The method also includes coating an interior surface and an exterior surface of each of the set of piezoelectric elements with a first conductive material. The method also includes providing a fiber optic element having an actuation region and coating the actuation region of the fiber optic element with a second conductive material. The method also includes joining the interior surfaces of the set of piezoelectric elements to the actuation region of the fiber optic element and poling the set of piezoelectric elements. The method also includes forming electrical connections to the exterior surface of each of the set of piezoelectric elements and the fiber optic element.

Abstract: A fiber scanning projector includes a piezoelectric element and a scanning fiber passing through and mechanically coupled to the piezoelectric element. The scanning fiber emits light propagating along an optical path. The fiber scanning projector also includes a first polarization sensitive reflector disposed along and perpendicular to the optical path. The first polarization sensitive reflector includes an aperture and the scanning fiber passes through the aperture. The fiber scanning projector also includes a second polarization sensitive reflector disposed along and perpendicular to the optical path.

Abstract: A retina image template matching method is based on the registration and comparison between the images captured with portable low-cost fundus cameras (e.g., a consumer grade camera typically incorporated into a smartphone or tablet computer) and a baseline image. The method solves the challenges posed by registering small and low-quality retinal template images captured with such cameras. Our method combines dimension reduction methods with a mutual information (MI) based image registration technique. In particular, principle components analysis (PCA) and optionally block PCA are used as a dimension reduction method to localize the template image coarsely to the baseline image, then the resulting displacement parameters are used to initialize the MI metric optimization for registration of the template image with the closest region of the baseline image.

Abstract: Disclosed is an improved diffraction structure for 3D display systems. The improved diffraction structure includes an intermediate layer that resides between a waveguide substrate and a top grating surface. The top grating surface comprises a first material that corresponds to a first refractive index value, the underlayer comprises a second material that corresponds to a second refractive index value, and the substrate comprises a third material that corresponds to a third refractive index value.

Abstract: An augmented reality system includes a light source configured to generate a virtual light beam. The system also includes a light guiding optical element having an entry portion, an exit portion, and a surface having a diverter disposed adjacent thereto. The light source and the light guiding optical element are configured such that the virtual light beam enters the light guiding optical element through the entry portion, propagates through the light guiding optical element by at least partially reflecting off of the surface, and exits the light guiding optical element through the exit portion. The light guiding optical element is transparent to a first real-world light beam. The diverter is configured to modify a light path of a second real-world light beam at the surface.

Abstract: A display assembly suitable for use with a virtual or augmented reality headset is described and includes the following: an input coupling grating; a scanning mirror configured to rotate about two or more different axes of rotation; an optical element; and optical fibers, each of which have a light emitting end disposed between the input coupling grating and the scanning mirror and oriented such that light emitted from the light emitting end is refracted through at least a portion of the optical element, reflected off the scanning mirror, refracted back through the optical element and into the input coupling grating. The scanning mirror can be built upon a MEMS type architecture.

Abstract: An augmented reality (AR) device is described with a display system configured to adjust an apparent distance between a user of the AR device and virtual content presented by the AR device. The AR device includes a first tunable lens that change shape in order to affect the position of the virtual content. Distortion of real-world content on account of the changes made to the first tunable lens is prevented by a second tunable lens that changes shape to stay substantially complementary to the optical configuration of the first tunable lens. In this way, the virtual content can be positioned at almost any distance relative to the user without degrading the view of the outside world or adding extensive bulk to the AR device. The augmented reality device can also include tunable lenses for expanding a field of view of the augmented reality device.