Meta Platforms Technologies, LLC

Facebook Technologies, LLC

Daniel Guenther Greif

Scott Charles McEldowney

Maxwell Parsons

Brian M Wheelwright

Stephen James McNally

Chadwick Brian Martin

James Laudolff

Jacques Gollier

Wanli Chi

Babak Amirsolaimani

Weichuan Gao

Ziv Magoz

Andrew John Ouderkirk

Giuseppe Calafiore

Fenglin Peng

Katherine Marie Smyth

Tanya Malhotra

Kenneth Alexander Diest

Jonathan Robert Peterson

Yang Yang

Renate Eva Klementine Landig

John Goward

Chloe Astrid Marie Fabien

Zhimin Shi

Stephen John Holmes

Kieran Connor Kelly

Taha Masood

Sihui He

Xiayu Feng

Miaomiao Xu

Nicholas John Diorio, Jr

An apparatus, system, and method for micro-electro-mechanical system (MEMS) micromirror including a plurality of stiffening structures is described. The MEMS micromirror includes a mirror surface to reflect light, a support platform coupled along a mirror surface, and a plurality of stiffening structures formed from or coupled to the support platform. In some examples, a dimensionality or density of the stiffening structures scale across an area of the support platform in a manner to assist in keeping the mirror surface flat under torsional force.

Stiffening structures for micro-electro-mechanical system (MEMS) micromirrors

A light source or projector for a near-eye display includes a light source subassembly optically coupled to a waveguide concentrator. The light source subassembly may include several semiconductor chips each hosting an array of emitters such s superluminescent light-emitting diodes. The semiconductor chips may be disposed side-by-side, with their emitting sides or facets coupled to the waveguide concentrator, which provides a tight array of output light ports on a common output plane of the concentrator. The output diverging beams at the array of output light ports are coupled to a collimator, which collimates the beams and couples them to an angular scanner for scanning the collimated light beams together across the field of view of the display.

Waveguide concentrator for light source

A pupil-replicating lightguide includes a slab of transparent material, a switchable out-coupling grating for out-coupling portions of image light to propagate towards an eyebox, and a switchable tracking grating for redirecting tracking light carrying an eye image towards an eye tracking camera. One of the two gratings may be turned ON while the other is turned OFF, in a time-sequential manner, allowing the combined use of the pupil-replicating lightguide for carrying image light and eye tracking light.

Eye tracking with switchable gratings

A beam scanner includes a substrate, a tiltable reflector hingedly supported by the substrate, and a reflective polarizer. The reflective polarizer is supported over the tiltable reflector and configured to receive and redirect a light beam towards the tiltable reflector for scanning the light beam. A projector includes the beam scanner and a light source providing a light beam. The light beam may be modulated in brightness, color, or polarization synchronously with tilting the reflector, thereby forming an image in angular domain after propagating through a pupil-replicating waveguide. At least one folding mirror may be provided for directing the light beam from the light source around the pupil-replicating waveguide, resulting in a compact overall configuration.

Folded-beam, low-obliquity beam scanner

A light source includes a first set of source elements and a second set of source elements. A respective set of source elements is disposed on a respective substrate and electrically coupled to a respective set of circuit pads formed on a respective top surface of the respective substrate by respective bond wires. At least a portion of the respective top surfaces face each other and are spaced apart from each other to accommodate at least some of the first set of source elements, at least some of the second set of source elements, and at least some of the bond wires. The display device that includes a light source configured to output image light, an optical assembly configured to collimate the image light, a scanning assembly configured to steer the image light, and an output device configured to output the image light for displaying images is also disclosed.

Compact array light source for scanning display

A scanning projector display includes a light engine comprising N emitters coupled to a collimator for providing a fan of N light beams of variable optical power levels, where N&#x3e;1. The N emitters are spaced apart from each other such that pixels of the image simultaneously energized by neighboring ones of the N emitters are non-adjacent. A scanner receives and angularly scans the fan of N light beams about first and second non-parallel axes to provide an image in angular domain. A controller coupled to the scanner and the light engine causes the scanner to simultaneously scan the fan of N light beams about the first and second axes, and cause the light engine to vary the optical power levels of the N emitters with time delays such that adjacent pixels of the image are energized by different ones of the N emitters.

Image painting with multi-emitter light source

A display device includes a relay waveguide and a scanner. The scanner is configured to angularly scan image light for coupling into the waveguide, and includes a scanning reflector and a second reflector disposed between the scanning reflector and an input coupler of the waveguide. The scanning reflector has an aperture for the image light to propagate therethrough toward the second reflector. The second reflector is configured to reflect at least a portion of the image light received through the aperture back toward the scanning reflector and to transmit at least a portion of the image light reflected from the scanning reflector toward the input coupler. The arrangement enables a compact design of the display.

Display with a compact beam scanner

A display device including a laser-based light engine is disclosed. Optical interference effects due to the coherent nature of a laser light source are mitigated by shortening a coherence length of the laser source. The coherence length shortening is achieved by at least one of the following: providing a multiple longitudinal mode laser source, pulsing a laser source to achieve spectral broadening, or providing multi-emitter laser source(s) with emission wavelength varying from emitter to emitter.

Suppressing coherence artifacts and optical interference in displays

A scanning projector for a display apparatus includes a first scanning reflector configured to steer a light beam in a first plane, a second scanning reflector configured to steer the light beam received from the first scanning reflector in a second plane, and beam relay optics configured to relay a first pupil defined at the first scanning reflector to a second pupil defined at the second scanning reflector, and to relay the second pupil to an output pupil of the scanning projector. The beam relay optics may include a concave reflector and a polarization beam splitter coupled to a scanning reflector in a triple pass configuration.

Scanning projector with multipath beam relay

A waveguide coupler may be coupled to a multi-beam light source, such as an array of superluminescent light-emitting diodes. The waveguide coupler includes a substrate having an end facet and a surface, e.g. a top flat surface, adjoining the end facet. At least one tilted reflector is supported by the substrate. A plurality of waveguides supported by the substrate extend between the end facet and the at least one tilted reflector. The at least one tilted reflector is configured to redirect light propagating in the plurality of waveguides to the surface of the substrate. In this manner, the waveguide coupler may provide an array of surface emission points on a substrate. All the surface emission points are disposed in one plane and may be suitably configured for subsequent joint collimation for use e.g. in a scanning projector display.

Integrated waveguide coupler and light source

A driver for powering a pulsed light source of a scanning projector display is configured to provide a succession of powering electric pulses to the light source. Duration of the powering electric pulses is less than a pixel time interval during which a scanner of the projector display is directing the light beam to form a corresponding pixel of the image to be displayed. The amplitude of the powering electric pulses is proportionally higher, such that the light pulse has a pulse energy similar to the light energy provided by the light source when continuously driven through the pixel time interval. This enables the light source to be operated at a steeper portion of the electro-optical transfer curve, thereby improving the wall plug efficiency of the scanning projector display.

Driving scanning projector display with pulses shorter than pixel duration

A controller for a tiltable MEMS reflector is configured to oscillate the reflector about X axis or about X and Y axes, and to obtain information about current and past tilt angles. The controller is configured to evaluate tilt angles of the tiltable MEMS reflector at a later moment of time based on the previously obtained information about the tilt angles of the tiltable MEMS reflector at the different earlier moments of time. The controller may be further configured to energize the light source providing a light beam to the tiltable MEMS reflector at the later moment of time with brightness and color corresponding to the brightness and color of a pixel that will be painted by the tiltable MEMS reflector at the later moment of time. A statistical model may be combined with machine learning to accurately predict future tilt angles of the tiltable MEMS reflector.

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Redmond, WA, United States of America

Daniel Guenther Greif