Omniphobic surface for use in user interface device

1. An apparatus, comprising:

a durable porous substrate having an elastic modulus of between 10 GPa and 200 GPa and comprising a multiplicity of tapered pillars formed with a surface of the durable porous substrate, wherein the durable porous substrate comprises a plurality of nanoparticles, each of the plurality of nanoparticles having a mean largest dimension between 10 nm and 250 μm; and

a perfluorinated liquid located within pores of the durable porous substrate, wherein the perfluorinated liquid is a fluoropolymer, the durable porous substrate and the perfluorinated liquid together configured to provide an omniphobic surface having an optical transmission of between 90% and 100%;

wherein the durable porous substrate and the perfluorinated liquid define a display screen;

wherein the display screen is self-repairing;

wherein the perfluorinated liquid is reflowable within the pores of the porous substrate to lower the surface energy of the porous substrate such that the omniphobic surface causes a liquid droplet to have a contact angle of greater than 90 degrees with the omniphobic surface;

wherein the durable porous substrate and the perfluorinated liquid form the omniphobic surface having a Fresnel reflectivity that is less than a Fresnel reflectivity of the durable porous substrate alone to provide a substantially transparent and anti-reflective surface; and

wherein the durable porous substrate comprises glass, and the fluoropolymer comprises fluoroacrylate polymer.

2. An apparatus according to claim 1 , wherein the durable porous substrate further comprises one or more of: glass, alumina, and diamond.

3. An apparatus according to claim 1 wherein the durable porous substrate is a durable substrate which has undergone an etching process to porosity the durable substrate and provide the durable porous substrate.

4. An apparatus according to claim 3 wherein the etching process comprises etching the durable substrate with hydrofluoric acid.

5. An apparatus according to claim 1 wherein the durable porous substrate comprises a porous layer between 10 nm and 500 μm in thickness.

6. An apparatus according to claim 1 wherein the durable porous substrate contains pores, the pores having a mean pore diameter between 10 nm and 250 μm.

7. An apparatus according to claim 1 wherein the apparatus is a module for the display screen or the display screen forms a part of a portable electronic device.

8. An apparatus according to claim 1 wherein the omniphobic surface is configured to resist the wetting of polar and non-polar liquid at the omniphobic surface.

9. An apparatus according to claim 1 wherein the omniphobic surface is configured to have a surface energy of 16 mN/m-20 mN/m.

10. A method, comprising:

providing a durable porous substrate having an elastic modulus of between 10 GPa and 200 GPa and comprising a multiplicity of tapered pillars formed with a surface of the durable porous substrate, wherein the durable porous substrate comprises a plurality of nanoparticles, each of the plurality of nanoparticles having a mean largest dimension between 10 nm and 250 μm; and

locating a perfluorinated liquid within pores of the durable porous substrate, wherein the perfluorinated liquid is a fluoropolymer, the durable porous substrate and the perfluorinated liquid together configured to provide an omniphobic surface having an optical transmission of between 90% and 100%;

lowering the surface energy of the porous substrate based on reflow of the perfluorinated liquid within the pores of the durable porous substrate such that the omniphobic surface causes a liquid droplet to have a contact angle of greater than 90 degrees with the omniphobic surface;

wherein the durable porous substrate and the perfluorinated liquid define a display screen;

wherein the display screen is self-repairing;

wherein the durable porous substrate and the perfluorinated liquid form the omniphobic surface having a Fresnel reflectivity that is less than a Fresnel reflectivity of the durable porous substrate alone to provide a substantially transparent and anti-reflective surface; and

wherein the durable porous substrate comprises glass, and the fluoropolymer comprises fluoroacrylate polymer.