Nano bi-material electromagnetic spectrum shifter

Patent metadata

Field	Value
Publication number	US-10191193-B2
Application number	US-201615281087-A
Country	US
Kind code	B2
Filing date	Sep 30, 2016
Priority date	Sep 30, 2015
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

The present invention relates to a nano bi-material, electromagnetic spectrum shifter based on said nano bi-material and method to produce said electromagnetic spectrum shifter using said nano bi-material. In particular, the present invention provides nano bi-material based electromagnetic spectrum shifter, e.g. color filters, with a wide range of transmission and color tunability and methods to produce said color filters. The present invention has applications in color filtration and production of color filters; reflector and production of reflectors; and electromagnetic spectrum shifter and production of electromagnetic spectrum shifters.

First claim

We claim:

1. A tunable electromagnetic spectrum shifter comprising: at least two different nano particles deposited as at least one layer onto at least one surface of one or more transparent, translucent, or reflective substrates; wherein the at least two different nano particles are plasmonically coupled and electromagnetic spectrum shifting is achieved via plasmonic coupling between the at least two different nano particles in the at least one layer of at least two different nano particles; wherein the at least two different nano particles are within 1-15 nm of each other on the at least one surface of an one or more transparent, translucent, or reflective substrate; and wherein relative positions of the at least two different nano particles in each pair of the at least two different nano particles are in random three-dimensional direction in respect with other pairs such that the at least two different nano particles in each of said at least one layer of at least two different nano particles are not arranged as one layer of one nano particles stacked on top of another layer of the other one nano particles.

2. The tunable electromagnetic spectrum shifter according to claim 1 , further comprising at least one transparent protective layer further deposited to protect said at least one layer of at least two different deposited nano particles.

3. The tunable electromagnetic spectrum shifter according to claim 1 wherein thickness of any one of said at least one layer of at least two different nano particles is at least 1 nm and no more than 15 nm.

4. The tunable electromagnetic spectrum shifter according to claim 1 wherein average nano particle size of any one of said at least two different nano particles is in a range of 10 nm to 60 nm in circular disc diameter.

5. The tunable electromagnetic spectrum shifter according to claim 1 wherein the distance between the at least two different nano particles is at least 1 nm.

6. The tunable electromagnetic spectrum shifter according to claim 1 wherein the at least two different nano particles comprise one nano metal particles and at least one other different nano particles being sequentially deposited onto said at least one surface of the one or more transparent, translucent, or reflective substrate to form said at least one layer of the at least two different nano particles.

7. The tunable electromagnetic spectrum shifter according to claim 6 wherein the one nano metal particles is composed of metals which are screened plasma frequency at near-ultraviolet region or visible spectral regions such that the resonance is tunable in the visible spectral region due to the red-shift phenomenon in the presence of said at least one other different nano particles which are within 1-15 nm of the one nano metal particles, and have a relatively lower absorption in visible spectral region such that a relatively higher overall transmittance is resulted in said shifter.

8. The tunable electromagnetic spectrum shifter according to claim 6 wherein the at least one other different nano particles is composed of materials comprising metal, metal oxide, metal carbonate, or inorganic compounds.

9. The tunable electromagnetic spectrum shifter according to claim 8 wherein when said metal oxide, metal carbonate and inorganic compounds are optically transparent the deposition thickness of the at least one other different nano particles is more than 15 nm.

10. The tunable electromagnetic spectrum shifter according to claim 6 wherein the at least one other different nano particles acts as a color modifier in said shifter.

11. The tunable electromagnetic spectrum shifter according to claim 1 wherein transmission or color of said shifter is tunable by varying materials for any one or more of the at least two different nano particles and/or by varying the deposition thickness of any one or more of the at least two different nano particles.

12. The tunable electromagnetic spectrum shifter according to claim 1 wherein said transparent or translucent substrate comprises glass, quartz, fused silica, and sapphire, and wherein said substrate has a smooth and unmarked or non-textured surface.

13. The tunable electromagnetic spectrum shifter according to claim 1 wherein one of said at least two different nano particles is metal based while the other of said at least two different nano particles is either metal based or an inorganic compound.

14. The tunable electromagnetic spectrum shifter according to claim 1 wherein said one of the at least two different nano particles is silver or aluminum nano particles while said the other of the at least two different nano particles comprises nano particles of chromium, aluminum, titanium, MoO3, Cs2CO3 and LiF.

15. The tunable electromagnetic spectrum shifter according to claim 2 wherein said transparent protective layer comprises alumina and poly(methyl methacrylate).

16. The tunable electromagnetic spectrum shifter according to claim 1 wherein said electromagnetic spectrum shifter comprises a tunable color filtration apparatus and a reflector.

17. A process of making the tunable electromagnetic spectrum shifter according to claim 1 comprising: depositing a first nano particles onto at least one surface of an one or more transparent, translucent, or reflective substrate via a first physical vapor deposition method;
depositing at least one further nano particles which is different to the first nano particles onto said substrate or the first nano particles via the first physical vapor deposition method or a second physical vapor deposition method in order to form at least one layer of two different nano particles;
depositing at least one transparent protective layer onto the surface of said at least one layer of two different nano particles via any one of the first and second physical vapor deposition methods physical vapor deposition method or a solution process or an adhesive process.

18. The process according to claim 17 , wherein the first physical deposition method and the second physical deposition method comprising resistive thermal evaporation, electron beam evaporation, sputtering and ion plating; wherein the solution process is a spin coating process; and wherein the adhesive process is a physical process of attaching a transparent adhesive film.

19. A tunable electromagnetic spectrum filter comprising: at least two different nano particles deposited as at least one layer onto at least one surface of an one or more transparent or translucent substrates; wherein the at least two different nano particles are plasmonically coupled and electromagnetic spectrum filtering is achieved via plasmonic coupling between the at least two different nano particles in the at least one layer of at least two different nano particles; wherein the at least two different nano particles are within 1-15 nm of each other on the at least one surface of an one or more transparent or translucent substrate; and wherein relative positions of the at least two different nano particles in each pair of the at least two different nano particles are in random three-dimensional direction in respect with other pairs such that the at least two different nano particles in each of said at least one layer of at least two different nano particles are not arranged as one layer of one nano particles stacked on top of another layer of the other one nano particles.

20. A tunable electromagnetic spectrum reflector comprising: at least two different nano particles deposited as at least one layer onto at least one surface of

Assignees

• Univ Hong Kong Baptist Univ

Inventors

• Cheah Kok Wai
• Ching Suet Ying

Classifications

• C03C2217/45

  Inorganic continuous phases · CPC title

• C23C14/18

  on other inorganic substrates · CPC title

• C03C17/38

  at least one coating being a coating of an organic material · CPC title

• C03C2217/479

  Metals · CPC title

• C03C2217/258

  Ti, Zr, Hf · CPC title