OMNIDIRECTIONAL REFLECTOR

• US 20110128616A1
• Filed: 02/05/2011
• Published: 06/02/2011
• Est. Priority Date: 08/12/2007
• Status: Active Grant

• Current Assignee: Toyota Motor Corporation
• Original Assignee: Toyota Motor Corporation, Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Ishii, Masahiko, Banerjee, Debasish, Zhang, Minjuan
• Granted Patent: US 9,063,291 B2
• Time in Patent Office: Days
• US Class Current: 359/359
• CPC Class Codes: G02B 5/0825 the reflecting layers comprising dielectric materials only
• CPC Class Codes: G02B 5/085 at least one of the reflecting layers comprising metal
• CPC Class Codes: G02B 5/285 comprising deposited thin solid films G02B5/281 - G02B5/289 take precedence; multilayered film filters for fibre optic multiplexing G02B6/29361

Abstract

An omnidirectional structural color (OSC) having a non-periodic layered structure. The OSC can include a multilayer stack that has an outer surface and at least two layers. The at least two layers can include at least one first index of refraction material layer A1 and at least one second index of refraction material layer B1. The at least A1 and B1 can be alternately stacked on top of each other with each layer having a predefined thickness d_A1 and d_B1, respectively. The d_A1 is not generally equal to the d_B1 such that the multilayer stack has a non-periodic layered structure.

Claims

1. An omnidirectional structural color (OSC) having a non-periodic layered structure, said OSC comprising:

a multilayer stack having an outer surface and at least two layers, said at least two layers having at least one first index of refraction material layer A1 and at least one second index of refraction material layer B1, said at least one A1 and B1 alternately stacked on top of each other;

said at least A1 and B1 having a predefined thickness of d_A1 and d_B1 with said d_A1 not generally equal to said d_B1 such that said multilayer stack has a non-periodic layered structure; and

wherein said multilayer stack has a first omnidirectional reflection band, said first omnidirectional reflection band reflecting more than 50% of a narrow band of electromagnetic radiation of less than 500 nanometers when said outer surface is exposed to a generally broad band of electromagnetic radiation (such as white light) at angles between 0 and 45 degrees normal to said outer surface.

2. The OSC of claim 1, further comprising at least one third index of refraction material layer C1 having a predefined thickness d_C1, said at least one A1, B1 and C1 alternately stacked on top of each other and said d_C1 thickness not generally equal to said d_A1 and d_B1.

3. The OSC of claim 2, wherein said first omnidirectional reflection band reflects more than 50% of a narrow band of electromagnetic radiation of less than 200 nanometers when said outer surface is exposed to a generally broad band of electromagnetic radiation at angles between 0 and 60 degrees normal to said outer surface.

4. The OSC of claim 2, wherein said first omnidirectional reflection band reflects more than 50% of a narrow band of electromagnetic radiation of less than 200 nanometers when said outer surface is exposed to a generally broad band of electromagnetic radiation at angles between 0 and 80 degrees normal to said outer surface.

5. The OSC of claim 2, wherein said first omnidirectional reflection band reflects more than 50% of a narrow band of electromagnetic radiation of less than 100 nanometers when said outer surface is exposed to a generally broad band of electromagnetic radiation at angles between 0 and 45 degrees normal to said outer surface.

6. The OSC of claim 2, wherein said multilayer stack has a second omnidirectional reflection band reflecting more than 50% of infrared electromagnetic radiation having a wavelength of less than 400 nanometers.

7. The OSC of claim 2, wherein A1, B1, and C1 are selected from a group consisting of titania, silica, mica, zirconium oxide, niobium oxide, chromium and silver.

8. The OSC of claim 2, further comprising at least one fourth index of refraction material layer D1 having a predefined thickness d_D1, said at least one A1, said at least one B1, said at least one C1 and said at least one D1 alternately stacked on top of each other and said multilayer stack having at least at least four layers;

said d_D1 thickness not generally equal to said d_A1, d_B1 and d_C1.

11. The OSC of claim 1, wherein A1, B1, C1 and D1 are selected from a group consisting of titania, silica, mica, zirconium oxide, niobium oxide, chromium and silver.

12. The OSC of claim 10, further comprising at least one fifth index of refraction material layer E1 having a predefined thickness d_E1, said at least one A1, said at least one B1, said at least one C1, said at least one D1 and said at least one E1 alternately stacked on top of each other and said multilayer stack having at least at least five layers;

said d_E1 thickness not generally equal to said d_A1, d_B1, d_C1 and d_D1.

13. The OSC of claim 12, wherein A1, B1, C1, D1 and E1 are separately selected from a group consisting of titania, silica, mica, zirconium oxide, niobium oxide, chromium and silver.

14. A process for omnidirectionally reflecting a narrow band of electromagnetic radiation, the process comprising:

providing a multilayer stack having an outer surface and at least two layers, the at least two layers having at least one first index of refraction material layer A1 and at least one second index of refraction material layer B1, the at least one A1 and B1 alternately stacked on top of each other;

the at least A1 and B1 having a predefined thickness of d_A1 and d_B1 with the d_A1 thickness not generally equal to the d_B1 thickness such that the multilayer stack has a non-periodic layered structure; and

providing a source of broadband electromagnetic radiation;

exposing the multilayer stack to the broad band electromagnetic radiation at angles between 0 and 45 degrees normal to the outer surface; and

reflecting more than 50% of a narrow band of electromagnetic radiation less than 500 nanometers wide.

15. The process of claim 14, further comprising the multilayer stack having at least three layers with at least one third index of refraction material layer C1 having a predefined thickness d_C1 not equal to d_A1 and d_B1, the at least one A1, B1 and C1 alternately stacked on top of each other.

16. The process of claim 15, further comprising the multilayer stack having at least four layers with at least one fourth index of refraction material layer D1 having a predefined thickness d_D1 not equal to d_A1, d_B1 or d_C1, the at least one A1, B1, C1 and D1 alternately stacked on top of each other.

17. The process of claim 15, further comprising the multilayer stack having at least five layers with at least one fifth index of refraction material layer E1 having a predefined thickness d_E1 not equal to d_A1, d_B1, d_C1 or d_D1, the at least one A1, B1, C1, D1 and E1 alternately stacked on top of each other.

18. The process of claim 15, further comprising reflecting more than 50% of infrared electromagnetic radiation having a wavelength of less than 400 nanometers.

19. The process of claim 15, wherein A1, B1 and C1 are selected from a group consisting of titania, silica, mica, zirconium oxide, niobium oxide, chromium and silver.

20. The process of claim 15, wherein A1, B1, C1 and D1 are selected from a group consisting of titania, silica, mica, zirconium oxide, niobium oxide, chromium and silver.

21. The process of claim 15, wherein A1, B1, C1, D1 and E1 are selected from a group consisting of titania, silica, mica, zirconium oxide, niobium oxide, chromium and silver.