Magic Leap, Inc.

Mauro Melli

Christophe Peroz

Pierre St Hilaire

Dianmin Lin

Evgeni Poliakov

Vikramjit Singh

Michael Anthony Klug

Frank Y Xu

Melanie Maputol West

Chulwoo Oh

Kang Luo

Michael Nevin Miller

Victor Kai Liu

Shuqiang Yang

David Carl Jurbergs

Jeffrey Dean Schmulen

Marlon Edward Menezes

Mohammadreza Khorasaninejad

Zongxing Wang

Samarth Bhargava

Sharad D Bhagat

Chieh Chang

Jason A Schaefer

Robert D TeKolste

Ling Li

Brian George Hill

Ali Karbasi

Evgeni Yuriy Poliakov

Antireflection coatings for metasurfaces are described herein. In some embodiments, the metasurface may include a substrate, a plurality of nanostructures thereon, and an antireflection coating disposed over the nanostructures. The antireflection coating may be a transparent polymer, for example a photoresist layer, and may have a refractive index lower than the refractive index of the nanostructures and higher than the refractive index of the overlying medium (e.g., air). Advantageously, the antireflection coatings may reduce or eliminate ghost images in an augmented reality display in which the metasurface is incorporated.

Antireflection coatings for metasurfaces

Metasurfaces provide compact optical elements in head-mounted display systems to, e.g., incouple light into or outcouple light out of a waveguide. The metasurfaces may be formed by a plurality of repeating unit cells, each unit cell comprising two sets or more of nanobeams elongated in crossing directions: one or more first nanobeams elongated in a first direction and a plurality of second nanobeams elongated in a second direction. As seen in a top-down view, the first direction may be along a y-axis, and the second direction may be along an x-axis. The unit cells may have a periodicity in the range of 10 nm to 1 μm, including 10 nm to 500 nm or 300 nm to 500 nm. Advantageously, the metasurfaces provide diffraction of light with high diffraction angles and high diffraction efficiencies over a broad range of incident angles and for incident light with circular polarization.

Diffraction gratings formed by metasurfaces having differently oriented nanobeams

The present disclosure relates to display systems and, more particularly, to augmented reality display systems. In one aspect, a method of fabricating an optical element includes providing a substrate having a first refractive index and transparent in the visible spectrum. The method additionally includes forming on the substrate periodically repeating polymer structures. The method further includes exposing the substrate to a metal precursor followed by an oxidizing precursor. Exposing the substrate is performed under a pressure and at a temperature such that an inorganic material comprising the metal of the metal precursor is incorporated into the periodically repeating polymer structures, thereby forming a pattern of periodically repeating optical structures configured to diffract visible light. The optical structures have a second refractive index greater than the first refractive index.

Optical elements based on polymeric structures incorporating inorganic materials

Display devices include waveguides with metasurfaces as in-coupling and/or out-coupling optical elements. The metasurfaces may be formed on a surface of the waveguide and may include a plurality or an array of sub-wavelength-scale (e.g., nanometer-scale) protrusions. Individual protrusions may include horizontal and/or vertical layers of different materials which may have different refractive indices, allowing for enhanced manipulation of light redirecting properties of the metasurface. Some configurations and combinations of materials may advantageously allow for broadband metasurfaces. Manufacturing methods described herein provide for vertical and/or horizontal layers of different materials in a desired configuration or profile.

Metasurfaces with light-redirecting structures including multiple materials and methods for fabricating

Plasma etching processes for forming patterns in high refractive index glass substrates, such as for use as waveguides, are provided herein. The substrates may be formed of glass having a refractive index of greater than or equal to about 1.65 and having less than about 50 wt % SiO. The plasma etching processes may include both chemical and physical etching components. In some embodiments, the plasma etching processes can include forming a patterned mask layer on at least a portion of the high refractive index glass substrate and exposing the mask layer and high refractive index glass substrate to a plasma to remove high refractive index glass from the exposed portions of the substrate. Any remaining mask layer is subsequently removed from the high refractive index glass substrate. The removal of the glass forms a desired patterned structure, such as a diffractive grating, in the high refractive index glass substrate.

Patterning of high refractive index glasses by plasma etching

An optical device includes a liquid crystal layer having a first plurality of liquid crystal molecules arranged in a first pattern and a second plurality of liquid crystal molecules arranged in a second pattern. The first and the second pattern are separated from each other by a distance of about 20 nm to about 100 nm along a longitudinal or a transverse axis of the liquid crystal layer. The first and the second plurality of liquid crystal molecules are configured as first and second grating structures that can redirect light of visible or infrared wavelengths.

Liquid crystal diffractive devices with nano-scale pattern and methods of manufacturing the same

A display system comprises a waveguide having light incoupling or light outcoupling optical elements formed of a metasurface. The metasurface is a multilevel (e.g., bi-level) structure having a first level defined by spaced apart protrusions formed of a first optically transmissive material and a second optically transmissive material between the protrusions. The metasurface also includes a second level formed by the second optically transmissive material. The protrusions on the first level may be patterned by nanoimprinting the first optically transmissive material, and the second optically transmissive material may be deposited over and between the patterned protrusions. The widths of the protrusions and the spacing between the protrusions may be selected to diffract light, and a pitch of the protrusions may be 10-600 nm.

Metasurfaces for redirecting light and methods for fabricating

In some embodiments, a display device includes one or more waveguides having a vapor deposited light absorbing film on edges of the waveguide to mitigate ghost images. In some embodiments, the film is formed directly on the edge of the waveguide by a vapor deposition, such as an evaporative deposition process. In some embodiments, the light absorbing films may comprise carbon, for example carbon in the form of one or more allotropes of carbon, such as fullerenes, or black silicon.

Waveguides with light absorbing films and processes for forming the same

The present disclosure generally relates to display systems, and more particularly to augmented reality display systems and methods of fabricating the same. A method of fabricating a display device includes providing a substrate comprising a lithium (Li)-based oxide and forming an etch mask pattern exposing regions of the substrate. The method additionally includes plasma etching the exposed regions of the substrate using a gas mixture comprising CHF3 to form a diffractive optical element, wherein the diffractive optical element comprises Li-based oxide features configured to diffract visible light incident thereon.

Method of fabricating display device having patterned lithium-based transition metal oxide

Methods are disclosed for fabricating molds for forming eyepieces having waveguides with integrated spacers. The molds are formed by etching deep holes (e.g., 5 &#x3bc;m to 1000 &#x3bc;m deep) into a substrate using a wet etch or dry etch. The etch masks for defining the holes may be formed with a thick metal layer and/or multiple layers of different metals. A resist layer may be disposed over the etch mask. The resist layer may be patterned to form a pattern of holes, the pattern may be transferred to the etch mask, and the etch mask may be used to transfer the pattern into the underlying substrate. The patterned substrate may be utilized as a mold onto which a flowable polymer may be introduced and allowed to harden. Hardened polymer in the holes may form integrated spacers. The hardened polymer may be removed from the mold to form a waveguide with integrated spacers.

Method of fabricating molds for forming eyepieces with integrated spacers

An optical system comprises an optically transmissive substrate comprising a metasurface which comprises a grating comprising a plurality of unit cells. Each unit cell comprises a laterally-elongated first nanobeam having a first width; and a laterally-elongated second nanobeam spaced apart from the first nanobeam by a gap, the second nanobeam having a second width larger than the first width. A pitch of the unit cells is 10 nm to 1 &#x3bc;m. The heights of the first and the second nanobeams are: 10 nm to 450 nm where a refractive index of the substrate is more than 3.3; and 10 nm to 1 &#x3bc;m where the refractive index is 3.3 or less.

Metasurfaces with asymetric gratings for redirecting light and methods for fabricating

An optical device includes a liquid crystal layer having a first plurality of liquid crystal molecules arranged in a first pattern and a second plurality of liquid crystal molecules arranged in a second pattern. The first and the second pattern are separated from each other by a distance of about 20 nm and about 100 nm along a longitudinal or a transverse axis of the liquid crystal layer. The first and the second plurality of liquid crystal molecules are configured as first and second grating structures that can redirect light of visible or infrared wavelengths.

A Procedural EBL system implements a user-provided oracle function (e.g., associated with a specific pattern) to generate control instructions for electron beam drive electronics in an on-demand basis. A control system may invoke the oracle function to query the pattern at individual point locations (e.g., individual x,y locations), and/or it may query the pattern over an area corresponding to a current field being addressed by the beam and stage positioner, for example. This Procedural EBL configuration manages control and pattern generation so that the low-level drive electronics and beam column may remain unchanged, allowing it to leverage existing EBL technologies.

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San Leandro, CA, United States of America

Mauro Melli