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US 11,598,919 B2Granted
Artificial reality system having Bragg grating
AssigneeMeta Platforms Technologies, LLC
InventorsYingfei Jiang, Lu Lu, Hao Yu
Life of this patent
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Abstract
An optical assembly may include a waveguide and a Bragg grating configured to couple light into or out of the waveguide. The Bragg grating may include a plurality of layer pairs, wherein at least one layer pair comprises a first material having a first refractive index and a second layer having a second refractive index, and wherein properties of the Bragg grating are selected so that the Bragg grating exhibits a substantially similar diffractive efficiency and diffraction angle for light of at least two colors.
Claims18
An optical assembly comprising:
- a waveguide;
- and
- a Bragg grating configured to couple light into or out of the waveguide, wherein the Bragg grating comprises a plurality of layer pairs, wherein at least one layer pair comprises a first material having a first refractive index and a second layer having a second refractive index, wherein properties of the Bragg grating are selected so that the Bragg grating exhibits a substantially similar diffractive efficiency and a substantially the same diffraction angle for light of at least two colors, wherein the properties of the Bragg grating are selected so that the Bragg grating exhibits a substantially similar diffractive efficiency for light of three colors, wherein each layer pair of the plurality of layer pairs comprises the first material and the second material, and wherein a thickness of each layer pair of the plurality of layer pairs is substantially the same.
A head mounted display comprising:
- a projector;
- and
- an optical assembly comprising:
- a waveguide;
- and
- a Bragg grating configured to couple light into or out of the waveguide, wherein the Bragg grating comprises a plurality of layer pairs, wherein a layer pair comprises a first material having a first refractive index and a second layer having a second refractive index, wherein properties of the Bragg grating are selected so that the Bragg grating exhibits a substantially similar diffractive efficiency and a substantially the same diffraction angle for light of at least two colors, wherein the properties of the Bragg grating are selected so that the Bragg grating exhibits a substantially similar diffractive efficiency for light of three colors, wherein each layer pair of the plurality of layer pairs comprises the first material and the second material, and wherein a thickness of each layer pair of the plurality of layer pairs is substantially the same, and wherein the projector is configured to direct light into the waveguide.
3 more elements
A method comprising:
- determining properties of a Bragg grating so that the Bragg grating exhibits a substantially similar diffractive efficiency and a substantially the same diffraction angle for light of at least two colors, wherein the properties of the Bragg grating are determined so that the Bragg grating exhibits a substantially similar diffractive efficiency for light of three colors, wherein the Bragg grating is configured to couple light into or out of a waveguide, wherein the Bragg grating comprises a plurality of layer pairs, wherein at least one layer pair comprises a first material having a first refractive index and a second layer having a second refractive index, wherein each layer pair of the plurality of layer pairs comprises the first material and the second material, and wherein a thickness of each layer pair of the plurality of layer pairs is substantially the same;
- and
- assembling the Bragg grating with a waveguide.
Dependencies are inferred from the claim text.