Nanovided spacer materials and corresponding systems and methods
A nanovoided spacer material that is used as a mechanical buffer between at least two optical components. The optical components may include gratings (e.g., Bragg gratings, moth-eye surfaces, etc.) having sensitive and fragile surfaces (e.g., patterned surfaces). The nanovoided spacers may have a predetermined thickness and concentration of nanovoids to provide a given optical property (e.g., a reflection coefficient at an interface between two optical elements). The nanovoided spacer may include a multilayer structure (e.g., two or more layers) of varying refractive index (e.g., to reduce reflections between surfaces of the optical elements). The nanovoided spacer may include from about 10% to 90% nanovoids by volume and may have an average index of refraction of about 1.15. Various other methods, systems, apparatuses, and materials are also disclosed.
1. An optical system, including:
a first optical component comprising a non-patterned surface and a patterned surface having a periodicity of about one nanostructure every 10 nm to 500 nm;
a second optical component spaced from the first optical component, the second optical component comprising a non-patterned surface and a patterned surface having a periodicity of about one nanostructure every 10 nm to 500 nm; and
a polymer material that defines a plurality of nanovoids, each having a diameter of approximately 1000 nm or less, and serves as a buffer between the first optical component and the second optical component, wherein:
a first surface of the polymer material is proximate to and coupled to the patterned surface of the first optical component; and
a second surface of the polymer material is proximate to and coupled to the patterned surface of the second optical component.
2. The optical system of claim 1 , wherein at least one of the first optical component or the second optical component comprises at least one of a refractive element, a polarizing element, or a reflective element.
3. The optical system of claim 1 , wherein a thickness of the polymer material and a concentration of the nanovoids per unit volume in the polymer material are configured to adjust an optical property associated with the optical system, the optical property including at least one of a reflectance, an absorption, or a transmittance of light incident on the optical system.
4. The optical system of claim 1 , wherein the polymer material further comprises:
a first region having a first refractive index corresponding to a first concentration of nanovoids per unit volume; and
a second region having a second refractive index corresponding to a second concentration of nanovoids per unit volume, the first region and the second region being overlapped in a thickness direction of the polymer material.
5. The optical system of claim 1 , wherein the polymer material comprises a concentration of the nanovoids per unit volume that is approximately 10% to approximately 90%.
6. The optical system of claim 1 , wherein the polymer material comprises an average refractive index of about 1.05 to about 1.3.
7. The optical system of claim 1 , wherein the polymer material is fabricated using at least one of a chemical vapor deposition process, a thermal evaporation process, or a spin-coating process.
8. The optical system of claim 1 , wherein the polymer material is laminated to the patterned surface of the first optical component or the patterned surface of the second optical component.
9. The optical system of claim 1 , wherein a surface of the first optical component or a surface of the second optical component is convex, concave, flat, or irregular.
10. The optical system of claim 1 , wherein the polymer material is coupled to the patterned surface of the first optical component or the patterned surface of the second optical component by an adhesive material.
11. The optical system of claim 10 , wherein the adhesive material comprises an index of refraction that is greater than approximately 1.05.
12. A head-mounted display, including:
a display;
a first optical component comprising a non-patterned surface and a patterned surface having a periodicity of about one nanostructure every 10 nm to 500 nm;
a second optical component spaced from the first optical component, the second optical component comprising a non-patterned surface and a patterned surface having a periodicity of about one nanostructure every 10 nm to 500 nm; and
a polymer material that defines a plurality of nanovoids, each having a diameter of approximately 1000 nm or less, and serves as a buffer between the first optical component and the second optical component, wherein:
a first surface of the polymer material is proximate to and coupled to the patterned surface of the first optical component; and
a second surface of the polymer material is proximate to and coupled to the patterned surface of the second optical component.
13. The head-mounted display of claim 12 , wherein the head-mounted display comprises an augmented reality device, a virtual reality device, or a mixed reality device.
14. The head-mounted display of claim 12 , wherein the first optical component or the second optical component comprises at least one of a refractive element, a polarizing element, or a reflective element.
15. The head-mounted display of claim 12 , wherein a thickness of the polymer material and a concentration of the nanovoids per unit volume in the polymer material are configured to adjust an optical property associated with the head-mounted display, the optical property including at least one of a reflectance, an absorption, or a transmittance of light in the head-mounted display.
16. The head-mounted display of claim 12 , wherein the polymer material comprises a concentration of the nanovoids per unit volume that is approximately 10% to approximately 90%.
17. A method, including:
positioning a first optical component comprising a non-patterned surface and a patterned surface having a periodicity of about one nanostructure every 10 nm to 500 nm;
positioning a second optical component spaced from the first optical component, the second optical component comprising a non-patterned surface and a patterned surface having a periodicity of about one nanostructure every 10 nm to 500 nm;
positioning a polymer material that defines a plurality of nanovoids, each having a diameter of approximately 1000 nm or less, and serves as a buffer between the first optical component and the second optical component, wherein:
a first surface of the polymer material is proximate to and coupling the patterned surface of the first optical component; and
a second surface of the polymer material is proximate to and coupling the patterned surface of the second optical component.
18. The method of claim 17 , wherein the polymer material comprises a concentration of the nanovoids per unit volume that is approximately 10% to approximately 90%.
19. The method of claim 17 , wherein the polymer material comprises an average refractive index of about 1.05 to about 1.3.