Elecronically tunable optical periodic surface filters with an alterable resonant frequency

• US 5,619,365 A
• Filed: 05/30/1995
• Issued: 04/08/1997
• Est. Priority Date: 06/08/1992
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Frazier, Gary, Ryan, Daniel J., Hoffman, Richard G. II, Rhoads, Charles M., Kesler, Oren B.
• Primary Examiner(s): Epps, Georgia Y.
• Assistant Examiner(s): Robbins, Thomas
• Application Number:
  US08/453,531
• Time in Patent Office: 679 Days
• Field of Search: 359/248, 359/291, 343/909
• US Class Current: 359/248
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G01S 3/781 Details
• CPC Class Codes: G02F 1/0126 Opto-optical modulation, i.e. control of one light beam by another light beam, not otherwise provided for in this subclass
• CPC Class Codes: G02F 1/015 based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction G02F1/03 takes precedence
• CPC Class Codes: G02F 1/017 Structures with periodic or quasi periodic potential variation, e.g. superlattices, quantum wells
• CPC Class Codes: G02F 1/01716 Optically controlled superlattice or quantum well devices
• CPC Class Codes: H01Q 15/002 said selective devices being reconfigurable or tunable, e.g. using switches or diodes
• CPC Class Codes: H01Q 3/2676 Optically controlled phased array
• CPC Class Codes: H01Q 3/46 Active lenses or reflecting arrays
• CPC Class Codes: H01S 3/105 by controlling the mutual position or the reflecting properties of the reflectors of the cavity , e.g. by controlling the cavity lengthH01S3/10076, H01S3/13 take precedence
• CPC Class Codes: H01S 3/115 using intracavity electro-optic devices

Abstract

Generally and in one form of the invention this is a periodic surface filter comprising at least one element at a surface of the filter and electronic controls to change the optical characteristics of the element. The surface filter comprising and electronically tunable electro-optic material to alter the resonant frequency of the element.

Claims

1. A tunable surface filter comprising:

a. at least one element at a surface of said filter; and

b. an electronically tunable electro-optic material to alter the resonant frequency of said element.

2. The filter of claim 1, wherein said tunable electro-optic material is a quantum well heterostructure.

3. The filter of claim 1, wherein electron state population and depletion is used to modulate the optical properties of said quantum well heterostructure.

4. The filter of claim 1, wherein said quantum well comprises a single quantum well fabricated such that population or de-population of electrons of the lowest conduction band quantum well state produces the maximum modulation of the center resonant frequency of said element.

5. The filter of claim 1, wherein said quantum well comprises a multiple quantum well superlattice fabricated such that population or de-population of electrons of the lowest conduction band superlattice state produces the maximum modulation of the center resonant frequency of said element.

6. The filter of claim 1, wherein a conducting overcoat electrically connects isolated elements.

7. The filter of claim 6, wherein said overcoat is metal.

8. The filter of claim 1, wherein a conducting undercoat electrically connects isolated elements.

9. The filter of claim 8, wherein said undercoat is metal.

10. The filter of claim 8, wherein said undercoat is a doped semiconductor.

11. The filter of claim 1, wherein said filter is a bandpass filter.

12. The filter of claim 1, wherein said filter is a bandreject filter.

13. The filter of claim 1, wherein said filter is periodic.