TUNABLE PLASMONIC FILTER

• US 20100046060A1
• Filed: 12/21/2007
• Published: 02/25/2010
• Est. Priority Date: 12/29/2006
• Status: Active Grant

• Current Assignee: NanoLambda, Inc.
• Original Assignee: Nanalambda Incorporated
• Inventors: Choi, Byung Il, Lee, Byounghee
• Granted Patent: US 8,462,420 B2
• Time in Patent Office: Days
• US Class Current: 359/277
• CPC Class Codes: G02F 1/19 based on variable-reflection or variable-refraction elements not provided for in groups G02F1/015 - G02F1/169
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G02F 2201/124 interdigital
• CPC Class Codes: G02F 2203/10 plasmon

Abstract

A tunable plasmonic filter or an optical filtering method discloses plasmonic filter structure and a voltage or current source. An intensity or wavelength of light transmitted through the filter structure is modulated by the intensity of a voltage or current from the voltage or current source. The plasmonic filter structure is located between electrodes electrically connected to the voltage or current source. The plasmonic filter structure is configured such that the incident light is resonant with at least one plasmonic mode on the structure, and a predetermined wavelength will perturb the metallic plasmonic structure in surface plasmon on energy bands for the wavelength selective transmission of light.

Claims

1. A tunable plasmonic filter comprising:

interdigitated plasmonic filter structures; and

a voltage or current source;

wherein an intensity or wavelength of light transmitted through the filter structures is modulated by intensity of a voltage or current from the voltage or current source, where one end of the source is connected to a first part of interdigitated plasmonic filter structure and the other end of the source is connected to a second part of interdigitated plasmonic filter structure.

2. A filter set forth in claim 1, wherein the first and second part of interdigitated plasmonic filter structures are configured such that the incident light is resonant with at least one plasmonic mode on the structures, and a predetermined wavelength will perturb the metallic plasmonic structures in surface plasmon energy bands for the wavelength selective transmission of light.

3. A filter set forth in claim 1, wherein the first and second part of interdigitated plasmonic filter structures are made of metal.

12. A transmissive flat panel display comprising the filter of claim 1.

13. A flat panel display set forth in claim 12, further comprising a light source which comprises a back light unit.

14. A reflective flat panel display comprising the filter of claim 1.

15. A flat panel display set forth in claim 14, further comprising an external light source which is used as a light source.

16. A multispectral imaging device comprising the filter of claim 1.

17. A photodetector array comprising the filter of claim 1.

18. An optical modulator comprising the filter of claim 1.

4. A tunable plasmonic filter comprising:

a plasmonic filter structure; and

a voltage or current source;

wherein an intensity or wavelength of light transmitted through the filter structure is modulated by intensity of a voltage or current from the voltage or current source; and

said plasmonic filter structure is located between electrodes electrically connected to the voltage or current source.

5. A filter set forth in claim 4, wherein the electrodes comprise optically transparent plates.

6. A filter set forth in claim 4, wherein the plasmonic filter structure is configured such that the incident light is resonant with at least one plasmonic mode on the structure, and a predetermined wavelength will perturb the metallic plasmonic structure in surface plasmon energy bands for the wavelength selective transmission of light.

7. A filter set forth in claim 4, wherein the plasmonic filter structure comprises a plurality of metal islands, or multiple apertures in a metal film or a metal embossing array on a metal film.

8. A tunable plasmonic filter comprising:

a plasmonic filter structure; and

a voltage or current source;

wherein an intensity or wavelength of light transmitted through the filter structures is modulated by intensity of a voltage or current from the voltage or current source; and

the plasmonic filter structure electrically contacts a substrate which is electrically connected to the voltage or current source.

9. A filter set forth in claim 8, wherein said substrate comprises an optically transparent piezoelectric material.

10. A filter set forth in claim 8, wherein the plasmonic filter structure is configured such that the incident light is resonant with at least one plasmonic mode on the structure, and a predetermined wavelength will perturb the metallic plasmonic structure in surface plasmon energy bands for the wavelength selective transmission of light.

11. A filter set forth in claim 8, wherein the plasmonic filter structure comprises a plurality of metal islands, or multiple apertures in a metal film or a metal embossing array on a metal film.

19. A tunable plasmonic filter, comprising:

a metal plasmonic filter comprising at least one of subwavelength sized plasmonic structures or apertures; and

a modulating voltage or current source which in operation is adapted to apply a voltage or current indirectly to, or between portions of, or to a substrate of the metal plasmonic filter to modulate at least one of intensity or wavelength of light transmitted through the filter.

20. An optical filtering method, comprising:

transmitting light through a metal plasmonic filter comprising at least one of subwavelength sized plasmonic structures or apertures, such that at least one plasmon mode on the filter is resonant with incident light to produce a transmitted filtered light; and

modulating at least one of intensity or wavelength of the transmitted light by a voltage or current applied indirectly to, or between portions of, or to a substrate of the metal plasmonic filter.