Tunable plasmonic filter

• US 8,462,420 B2
• Filed: 12/21/2007
• Issued: 06/11/2013
• Est. Priority Date: 12/29/2006
• Status: Active Grant

• Current Assignee: NanoLambda, Inc.
• Original Assignee: NanoLambda, Inc.
• Inventors: Lee, Byounghee, Choi, Byung Il
• Primary Examiner(s): TRA, TUYEN Q
• Application Number:
  US12/521,416
• Publication Number:
  US 20100046060A1
• Time in Patent Office: 1,999 Days
• Field of Search: 359/277, 359/276, 359/278, 359/282, 359/284, 359/286, 359/287
• 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:

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 operable for applying 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,

wherein the metal plasmonic filter comprises interdigitated plasmonic filter structures, and

wherein the modulating voltage or current source is adapted to apply a voltage or current to a first part and a second part of the interdigitated plasmonic filter structures, and

wherein the first and second parts of the interdigitated plasmonic filter structures are configured such that incident light is resonant with at least one plasmonic mode on the interdigitated plasmonic filter structures, and a predetermined wavelength perturbs the interdigitated plasmonic structures in surface plasmon energy bands for wavelength selective transmission of light.

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

3. The flat panel display of claim 2, further comprising a light source which comprises a back light unit.

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

5. The flat panel display of claim 4, further comprising an external light source.

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

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

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

9. The filter of claim 1, wherein the modulating voltage or current source is operable for applying a voltage or current indirectly to, or between portions of, or to a substrate of the metal plasmonic filter to modulate intensity of light transmitted through the filter.

10. The filter of claim 1, wherein the modulating voltage or current source is operable for applying a voltage or current indirectly to, or between portions of, or to a substrate of the metal plasmonic filter to modulate wavelength of light transmitted through the filter.

11. 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 operable for applying 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,

wherein the metal plasmonic filter is located between electrodes connected to the modulating voltage or current source, and

wherein the metal plasmonic filter comprises plasmonic filter structures configured such that incident light is resonant with at least one plasmonic mode on the structures, and a predetermined wavelength perturbs the plasmonic structures in surface plasmon energy bands for wavelength selective transmission of light.

12. 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,

wherein the metal plasmonic filter electrically contacts the substrate which is electrically connected to the modulating voltage or current source, and

wherein the metal plasmonic filter comprises plasmonic filter structures configured such that incident light is resonant with at least one plasmonic mode on the structures, and a predetermined wavelength perturbs the plasmonic structures in surface plasmon energy bands for wavelength selective transmission of light.

13. 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;

wherein the step of transmitting light through the metal plasmonic filter comprises transmitting light through the metal plasmonic filter located between electrodes connected to the modulating voltage or current source; and

wherein the metal plasmonic filter is configured such that a predetermined wavelength perturbs the plasmonic structures in surface plasmon energy bands for wavelength selective transmission of light.