# US 11,906,743 B2 · Display for augmented reality or virtual reality > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,906,743 B2 - Document ID: US11906743B2 - Status: Granted - Kind: B2 - Application number: 17/432,036 - Filed: 2020-01-20 - Published: 2022-06-09 - Granted: 2024-02-20 - Earliest claimed: 2019-03-07 - Assignees: Snap Inc. - Applicants: Snap Inc. - Inventors: Mohmed Salim Valera - Web page: https://patentgrep.com/patent/US11906743B2 ## CPC - G02B 27/0172: {characterised by optical features} - G02B 27/0056: {by using a diffractive optical element} - G02B 27/0081: {with means for altering, e.g. enlarging, the entrance or exit pupil} - G02B 27/1006: {for splitting or combining different wavelengths (G02B27/1086, G02B27/141 take precedence)} - G02B 2027/0123: {comprising devices increasing the field of view} - G02B 2027/0178: {Eyeglass type (eyeglass details G02C)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An augmented reality or virtual reality display device is disclosed. A first input grating (6; 106; 306; 406; 506) is provided on a waveguide assembly to receive light from a first projector (2; 102; 202; 302; 402; 502) and to couple the light into the at least one waveguide. A second input grating (116; 316; 416; 516) is provided to receive light from a second projector (12; 112; 212; 312; 412; 512) and couple the light into the at least one waveguide. An output diffractive optical element couples light out of the at least one waveguide towards a notional viewing position. The first projector provides light to the first input diffractive optical element in a direction that is at a first angle to a waveguide normal vector, and the second projector is configured to provide light to the second input diffractive optical element in a direction that is at a second angle to the waveguide normal vector. The output diffractive optical element is configured to couple light out of the at least one waveguide in a first range of angles for light from the first projector and in a second range of angles for light from the second projector, wherein the first range of angles and the second range of angles are different but are partially overlapping. ## Claims ### Claim 1 An augmented reality or virtual reality display device, comprising: a first projector and a second projector; at least one waveguide assembly, comprising at least one waveguide; a first input diffractive optical element positioned in or on the at least one waveguide assembly configured to receive light from the first projector and to couple the light into the at least one waveguide; a second input diffractive optical element positioned in or on the at least one waveguide assembly configured to receive light from the second projector and to couple the light into the at least one waveguide; an output diffractive optical element positioned in or on the at least one waveguide assembly configured to couple light out of the at least one waveguide towards a notional viewing position; wherein the first projector is configured to provide light to the first input diffractive optical element in a direction that is at a first angle to a waveguide normal vector, and the second projector is configured to provide light to the second input diffractive optical element in a direction that is at a second angle to the waveguide normal vector; wherein the output diffractive optical element is configured to couple light out of the at least one waveguide in a first range of angles for light from the first projector and in a second range of angles for light from the second projector, wherein the first range of angles and the second range of angles are different but are partially overlapping; and wherein the first and second angles are angled respectively away from the output diffractive optical element. ### Claim 2 (depends on 1) The display device of claim 1, wherein the at least one waveguide assembly comprises a first waveguide assembly and a second waveguide assembly, respectively comprising at least one waveguide, and wherein the first input diffractive optical element is configured to couple light from the first projector into the at least one waveguide in the first waveguide assembly and the second input diffractive optical element is configured to couple light from the second projector into the at least one waveguide in the second waveguide assembly. ### Claim 3 (depends on 2) The display device of claim 2, wherein the first waveguide assembly is a stack of waveguides and wherein there is a plurality of first input diffractive optical elements respectively positioned in or on each waveguide in the stack of waveguides, and wherein the first projector is configured to provide a plurality of wavelengths of light which are coupled by the plurality of first input diffractive optical elements into the stack of waveguides. ### Claim 4 (depends on 3) The display device of claim 3, wherein the second waveguide assembly is a stack of waveguides and wherein there is a plurality of second input diffractive optical elements respectively positioned in or on each waveguide in the stack of waveguides, and wherein the second projector is configured to provide a plurality of wavelengths of light which are coupled by the plurality of second input diffractive optical elements into the stack of waveguides. ### Claim 5 (depends on 1) The display device of claim 1, comprising a third projector configured to provide light to a third input diffractive optical element in a direction that is at a third angle to a waveguide normal vector, and wherein the output diffractive optical element is configured to couple light out of the at least one waveguide in a third range of angles for light from the third projector, wherein the second range of angles and the third range of angles are partially overlapping. ### Claim 6 (depends on 2) The display device of claim 2, wherein the first and second projectors are positioned so that they provide light directly to first and second waveguide assemblies. ### Claim 7 (depends on 6) The display device of claim 6, wherein the first and second input diffractive optical elements are offset from one another in the first and second waveguide assemblies so that light can be coupled directly from the first and second projectors to the first and second input diffractive optical elements respectively. ### Claim 8 (depends on 1) The display device of claim 1, wherein the first and second input diffractive optical elements are positioned in or on the at least one waveguide assembly on either side of the output diffractive optical element. ### Claim 9 (depends on 8) The display device of claim 8, comprising a periscope for coupling light from the first projector to the first input diffractive optical element so that the first projector and the second projector can be positioned on the same side of the output diffractive optical element. ### Claim 10 (depends on 8) The display device of claim 8, wherein the first and second input diffractive optical elements are positioned above and below the output diffractive optical element from the perspective of a user. ### Claim 11 (depends on 8) The display device of claim 8, wherein the first and second input diffractive optical elements are positioned to the left and right of the output diffractive optical element from the perspective of a user. ### Claim 12 (depends on 11) The display device of claim 11, further comprising a third projector and a fourth projector, and a third input diffractive optical element and a fourth input diffractive optical element, wherein the third and fourth input diffractive optical elements are positioned above and below the output diffractive optical element from the perspective of a user. ### Claim 13 (depends on 1) The display device of claim 1, further comprising a prism positioned between the first projector and the at least one waveguide assembly to reduce the spread of angles of light rays from the first projector where they encounter the at least one waveguide assembly. ### Claim 14 (depends on 9) The display device of claim 9, wherein the first and second input diffractive optical elements are positioned above and below the output diffractive optical element from the perspective of a user. ### Claim 15 (depends on 9) The display device of claim 9, wherein the first and second input diffractive optical elements are positioned to the left and right of the output diffractive optical element from the perspective of a user. ### Claim 16 A method for projecting light via an augmented reality or virtual reality display device, comprising: projecting light from a first projector; directing the light from the first projector toward a first input diffractive optical element positioned in or on at least one waveguide assembly having at least one waveguide in a direction that is at a first angle to a waveguide normal vector; coupling the light from the first projector into at the least one waveguide; projecting light from a second projector; directing the light from the second projector toward a second input diffractive optical element positioned in or on the at least one waveguide assembly in a direction that is at a second angle to the waveguide normal vector; coupling the light from the second projector into the at least one waveguide; and coupling light out of the at least one waveguide towards a notional viewing position via an output diffractive optical element positioned in or on the at least one waveguide assembly; wherein the output diffractive optical element is configured to couple light out of the at least one waveguide in a first range of angles for light from the first projector and in a second range of angles for light from the second projector, wherein the first range of angles and the second range of angles are different but are partially overlapping; and wherein the first and second angles are angled respectively away from the output diffractive optical element. ### Claim 17 (depends on 16) The method of claim 16, wherein the at least one waveguide assembly comprises a first waveguide assembly and a second waveguide assembly, respectively comprising at least one waveguide, and wherein the first input diffractive optical element is configured to couple light from the first projector into the at least one waveguide in the first waveguide assembly and the second input diffractive optical element is configured to couple light from the second projector into the at least one waveguide in the second waveguide assembly. ### Claim 18 (depends on 17) The method of claim 17, wherein the first waveguide assembly is a stack of waveguides and wherein there is a plurality of first input diffractive optical elements respectively positioned in or on each waveguide in the stack of waveguides, and wherein the first projector is configured to provide a plurality of wavelengths of light which are coupled by the plurality of first input diffractive optical elements into the stack of waveguides. ### Claim 19 (depends on 18) The method of claim 18, wherein the second waveguide assembly is a stack of waveguides and wherein there is a plurality of second input diffractive optical elements respectively positioned in or on each waveguide in the stack of waveguides, and wherein the second projector is configured to provide a plurality of wavelengths of light which are coupled by the plurality of second input diffractive optical elements into the stack of waveguides. ### Claim 20 (depends on 16) The method of claim 16, further comprising: projecting light from a third projector; and directing the light from the third projector to a third input diffractive optical element in a direction that is at a third angle to a waveguide normal vector; wherein the output diffractive optical element is configured to couple light out of the at least one waveguide in a third range of angles for light from the third projector, wherein the second range of angles and the third range of angles are partially overlapping.