Low reflection articles and related systems and methods
Low reflection articles, and related systems and methods are disclosed. The articles have a surface with primary pores and secondary pores. At least some of the secondary pores contain agent, such, for example, a light absorbing dye.
1. A system, comprising:
an article, comprising a substrate comprising a metal,
wherein:
a surface of the substrate comprises primary pores and secondary pores;
an average diameter of the primary pores is at least four times greater than an average diameter of the secondary pores; and
the system comprises an optical system.
2. The system of claim 1 , wherein the average diameter of the primary pores is at least five times greater than the average diameter of the secondary pores.
3. The system of claim 1 , wherein the average diameter of the primary pores is at least 500 nm.
4. The system of claim 1 , wherein the average diameter of the primary pores is at least 1 μm.
5. The system of claim 1 , wherein the average diameter of the primary pores is at most 5 μm.
6. The system of claim 1 , wherein the article has a region which comprises the primary pores, and the region of the article has a porosity ratio of at least 0.1.
7. The system of claim 1 , wherein the article has a region which comprises the primary pores, and the region of the article has a porosity ratio of at most 0.3.
8. The system of claim 1 , wherein the average diameter of the secondary pores is at most 250 nm.
9. The system of claim 1 , wherein the average diameter of the secondary pores is at least 50 nm.
10. The system of claim 1 , wherein the secondary pores have an average aspect ratio of at least 10.
11. The system of claim 1 , wherein the secondary pores have an average aspect ratio of at most 40.
12. The system of claim 1 , further comprising a light absorbing agent.
13. The system of claim 12 , wherein at least some of the secondary pores comprise the light absorbing agent.
14. The system claim 13 , wherein the light absorbing agent comprises a visible light absorbing agent.
15. The system claim 13 , wherein the light absorbing agent comprises a dye.
16. The system claim 15 , wherein the dye comprises a water-soluble dye.
17. The system of claim 1 , wherein the surface of the article has a fractional reflectance of at most 0.0002 at a wavelength of from 400 nm to 700 nm.
18. The system of claim 1 , wherein:
the surface of the article has a first fractional reflectance at a first wavelength of from 400 nm to 700 nm;
the surface of the article has a second fractional reflectance at a second wavelength of from 400 nm to 700 nm;
the first wavelength is different from the second wavelength; and
the first fractional reflectance is different from the second fractional reflectance.
19. The system of claim 1 , wherein the surface of the article has a fractional reflectance of at most 0.0002 at a wavelength of from 10 nm to 400 nm.
20. The system of claim 1 , wherein the metal comprises a member selected from the group consisting of aluminum, titanium, niobium, tantalum, magnesium and zinc.
21. The system of claim 1 , wherein a portion of the substrate comprises an oxide, and the oxide comprises the metal.
22. The system of claim 21 , wherein the secondary pores are present in the portion of the oxide.
23. The system of claim 1 , wherein the surface of the article comprises a fluoro-aluminate.
24. The system of claim 1 , wherein the surface of the article comprises a hydrated aluminum oxide.
25. The system of claim 1 , wherein the system comprises a member selected from the group consisting of a holographic projection apparatus, a camera, a telescope, a color selective filter, a housing for a photonic sensor, a solar collector, a thermal solar system, an information display system, and a system for storing light sensitive materials.
26. A system, comprising:
an article, comprising a substrate comprising a metal,
wherein:
a surface of the substrate comprises primary pores and secondary pores;
an average diameter of the primary pores is from 500 nm to 15 μm; and
an average diameter of the secondary pores 50 nm to about 250 nm.
27. The system of claim 26 , wherein an average diameter of the primary pores is at least four times greater than an average diameter of the secondary pores.
28. The system of claim 26 , wherein the system comprises a member selected from the group consisting of a holographic projection apparatus, a camera, a telescope, a color selective filter, a housing for a photonic sensor, a solar collector, a thermal solar system, an information display system, and a system for storing light sensitive materials.
29. The system of claim 26 , wherein the system comprises an optical system.