Micro-dynamic optical device

• US 6,384,953 B1
• Filed: 06/29/2000
• Issued: 05/07/2002
• Est. Priority Date: 06/29/2000
• Status: Expired due to Term

• Current Assignee: The Government Of The United States As Represented By The Secretary Of The Navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Russell, Stephen D., Shimabukuro, Randy L.
• Primary Examiner(s): Dang, Hung Xuan
• Assistant Examiner(s): TRA, TUYEN Q
• Application Number:
  US09/607,579
• Time in Patent Office: 677 Days
• Field of Search: 359/585, 359/578, 359/579, 359/245, 359/263, 359/254, 359/250, 359/298, 359/318, 359/320, 359/322, 359/222, 359/586, 359/588, 359/584, 359/267, 359/260, 349/105, 349/106, 349/196
• US Class Current: 359/245
• CPC Class Codes: G01J 3/26 using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 5/008 Surface plasmon devices diffractive gratings with a pitch less than or comparable to the wavelength G02B5/1809; surface plasmons in integrated optics G02B6/1226; optical analysis of materials by means of surface plasmons G01N21/553

Abstract

Disclosed is an optical modulating device capable of use as a light-valve, display, optical filter or Fabry-Perot cavity, for example. The device lends itself to batch processing, and is compatible with monolithic integration with silicon, silicon-germanium, silicon-on-sapphire (SOS) or silicon-on-quartz (SOQ) advanced microelectronic technology (NMOS, PMOS and CMOS) for integrated control circuitry, electrical addressing, system interfacing, and the like. The device forgoes the complexities of liquid crystal constructions, and avoids the need to position and fix piezoelectric spacers within layers of the device. The invention includes first and second transparent layers that are disposed to oppose one another. Metallic layers are disposed upon the inwardly facing surfaces of the transparent layers and these are arranged to oppose each other. Spectral coupling layers are disposed upon the outwardly facing surfaces of the transparent layers opposite of the metallic layers. Electrodes are disposed upon the inwardly facing surface of the first and second transparent layers. An optical cavity is created between the metallic layers, and voltage is applied to the opposing electrodes to adjust the air gap between the metallic layers. Adjustment of this air gap permits light passing through the device to be controlled. To facilitate movement of one transparent layer with respect to another, one or more flexible portions are incorporated into at least one of the layers.

Claims

1. A light valve comprising:

first and second transparent layers, said layers disposed to oppose one another and thereby have inwardly facing surfaces and outwardly facing surfaces;

first and second metallic layers, one such metallic layer disposed upon a portion of said inwardly facing surface of said first transparent layer and the other said metallic layer disposed upon a portion of said inwardly facing surface of said second transparent layer wherein said metallic layers are disposed to oppose each other; and

first and second spectral coupling layers, one such spectral coupling layer disposed upon said outwardly facing surface of said first transparent layer opposite of said first metallic layer and the other said spectral coupling layer disposed upon said outwardly facing surface of said second transparent layer opposite of said second metallic layer;

wherein said metallic layers are spaced-apart to create an air gap therebetween, said metallic layers and said air gap creating an optical cavity through which light is selectively transmitted, and wherein said air gap is adjustable upon an application of heat to said layers so that light passed through said optical cavity is controlled.

2. The light valve according to claim 1 wherein said light valve is produced in batch processing.

3. The light valve according to claim 1 wherein said light valve is produced through batch processing in which said light valve is manufactured in halves each including a said transparent layer, a said metallic layer, and a said spectral coupling layer, wherein said halves are then aligned in opposing couples.

4. The light valve according to claim 3 wherein said halves are fabricated in substantially the same plane.

5. The light valve according to claim 1 wherein surface plasmon resonance is generated at each of the interfaces of said metallic layers and said air gap.

6. The light valve according to claim 1 wherein said metallic layers are of the same metal and thickness.

7. The light valve according to claim 1 wherein a change in said air gap has the effect of changing the wavelength of said light transmitted through said optical cavity.

8. The light valve according to claim 1 wherein said coupling layers include diffraction gratings.

9. The light valve according to claim 1 wherein said metallic layers are silver.

10. The light valve according to claim 1 wherein said metallic layers are each a combination of metal layers.

11. The light valve according to claim 1 wherein said metal layers are chosen from the group of Al, Ag, Au and Rh.

12. The light valve according to claim 1 wherein said first transparent layers is movable with respect to said second transparent layer, said first transparent layer including integral flexible mounts to enable said air gap to lessen or enlarge.

13. The light valve according to claim 12 wherein said flexible mounts each include a cantilever.

14. The light valve according to claim 12 wherein said light valve is produced through batch processing.

15. A light valve comprising:

first and second transparent layers, said layers disposed to oppose one another and thereby have inwardly facing surfaces and outwardly facing surfaces;

first and second metallic layers, one such metallic layer disposed upon a portion of said inwardly facing surface of said first transparent layer and the other said metallic layer disposed upon a portion of said inwardly facing surface of said second transparent layer wherein said metallic layers are disposed to oppose each other;

first and second spectral coupling layers, one such spectral coupling layer disposed upon said outwardly facing surface of said first transparent layer opposite of said first metallic layer and the other said spectral coupling layer disposed upon said outwardly facing surface of said second transparent layer opposite of said second metallic layer; and

first and second electrodes, one such electrode disposed upon a portion of said inwardly facing surface of said first transparent layer and the other said electrode disposed upon a portion of said inwardly facing surface of said second transparent layer wherein said electrodes are disposed to oppose each other;

wherein said metallic layers are spaced-apart to create an air gap therebetween, said metallic layers and said air gap creating an optical cavity through which light is selectively transmitted, and wherein said air gap is adjustable upon an application of voltage to said electrodes so that light passed through said optical cavity is controlled.

16. The light valve according to claim 15 wherein said light valve is produced in batch processing.

17. The light valve according to claim 15 wherein said light valve is produced through batch processing in which said light valve is manufactured in halves each including a said transparent layer, a said metallic layer, a said spectral coupling layer and a said electrode, wherein said halves are then aligned in opposing couples.

18. The light valve according to claim 17 wherein said halves are fabricated in substantially the same plane.

19. The light valve according to claim 15 wherein surface plasmon resonance is generated at each of the interfaces of said metallic layers and said air gap.

20. The light valve according to claim 15 wherein said metallic layers are of the same metal and thickness.

21. The light valve according to claim 15 wherein a change in said air gap has the effect of changing the wavelength of said light transmitted through said optical cavity.

22. The light valve according to claim 15 further including a variable voltage supply connected to said first and second electrodes so that said electrodes may be selectively drawn together by application of voltage thereto to change said air gap and thereby alter a characteristic of said light transmitted through said optical cavity.

23. The light valve according to claim 22 wherein said characteristic of said light is wavelength.

24. The light valve according to claim 15 wherein said coupling layers include diffraction gratings.

25. The light valve according to claim 15 wherein said metallic layers are silver.

26. The light valve according to claim 15 wherein said metallic layers are each a combination of metal layers.

27. The light valve according to claim 15 wherein said metal layers are chosen from the group of Al, Ag, Au and Rh.

28. The light valve according to claim 15 wherein said first transparent layers is movable with respect to said second transparent layer, said first transparent layer having integral flexible mounts to enable said air gap to lessen or enlarge according to application of said voltage.

29. The light valve according to claim 28 wherein said flexible mounts each include a cantilever.

30. The light valve according to claim 28 wherein said light valve is produced through batch processing.