Optical identification element having non-waveguide photosensitive substrate with diffraction grating therein

• US 20050220408A1
• Filed: 02/22/2005
• Published: 10/06/2005
• Est. Priority Date: 02/19/2004
• Status: Active Grant

• Current Assignee: Illumina Incorporated
• Original Assignee: CyVera Corporation (Illumina Incorporated)
• Inventors: Putnam, Martin A.
• Granted Patent: US 7,433,123 B2
• Time in Patent Office: Days
• US Class Current: 385/37
• CPC Class Codes: G02B 6/021 characterised by the core or cladding or coating, e.g. materials, radial refractive index profiles, cladding shape
• CPC Class Codes: G06K 19/06018 one-dimensional coding
• CPC Class Codes: G06K 19/06046 Constructional details

Abstract

An optical identification element (also known herein as a microbead) is provided made from pieces of an optical fiber or substrate that includes an inner core or region being surrounded by an outer cladding region, the optical fiber or substrate having an identification code imparted therein containing coded information. The identification code may be in the form of a Bragg grating inscribed or written in either the inner core or outer cladding. The optical identification element may be microscopic in size having a length in a range of 1-1,000 microns or smaller; or for larger applications may have a length of 1.0-1,000 millimeters or more. The outer diameter may be as small as less than 1,000 microns, as well as in a range of 1.0 to 1,000 millimeters for larger applications. Using manufacturing techniques developed in conjunction with the development of the element, one optical fiber or substrate can be drawn and processed to produce hundreds of thousands, as well as even a million or more of such unique microbeads.

Claims

1. An optical identification element comprising an optical substrate that includes an inner region being surrounded by an outer region, the optical substrate having an identification code imparted therein.

2. A optical identification element according to claim 1, wherein the identification code is written in the optical substrate as a Bragg grating.

3. A optical identification element according to claim 1, wherein the identification code is written in the inner region.

4. A optical identification element according to claim 1, wherein the identification code is written in the outer region.

5. A optical identification element according to claim 1, wherein the inner region has an index of refraction less than or equal to the outer region.

6. A optical identification element according to claim 1, wherein the outer region has an index of refraction less than or equal to the inner region.

7. A optical identification element according to claim 1, wherein the inner region is a photosensitive optical region.

8. A optical identification element according to claim 1, wherein the outer region is a non-photosensitive optical region.

9. An optical identification element comprising an inner region being surrounded by an outer region, having an index of refraction less than or equal to the outer region, and also having the Bragg grating inscribed therein.

10. A optical identification element according to claim 9, wherein the inner region is a photosensitive optical region.

11. A optical identification element according to claim 9, wherein the outer region is a non-photosensitive optical region.

12. A optical identification element according to claim 9, wherein the photosensitive optical region has a diameter that is no larger than 30 microns.

13. A optical identification element according to claim 9, wherein the photosensitive optical region has a diameter that is about 12 microns.

14. A optical-identification element according to claim 13 wherein the non-photosensitive optical region has a diameter that is in a range of 30-130 microns.

15. A optical identification element according to claim 9, wherein the photosensitive optical region has a diameter that is about 24 microns, and the non-photosensitive optical region has a diameter that is about 125 microns.

16. A optical identification element according to claim 9, wherein the photosensitive optical region has a diameter that is about 12 microns, and the non-photosensitive optical region has a diameter that is about 65 microns.

17. A optical identification element according to claim 9, wherein the photosensitive optical region has a diameter that is about ⅕

the diameter of the non-photosensitive optical region.

18. A optical identification element according to claim 10, wherein the photosensitive optical region is doped with Boron.

19. A optical identification element according to claim 10, wherein the photosensitive optical region is doped with excess amounts of Boron when compared to the amount of doping used for a standard telecom optical fiber.

20. A microbead comprising an optical element having a photosensitive core surrounded by a non-photosensitive cladding, the photosensitive core having an index of refraction less than or equal to the non-photosensitive cladding so as not to form an optical waveguide, and the photosensitive optical region also having a Bragg grating inscribed therein.

21. A microbead according to claim 20, wherein the photosensitive core has a diameter that is no larger than 30 microns.

22. A microbead according to claim 20, wherein the photosensitive core has a diameter that is about 12 microns.

23. A microbead according to claim 20, wherein the non-photosensitive cladding has a diameter that is in a range of 30-130 microns.

24. A microbead according to claim 20, wherein the photosensitive core has a diameter that is about 24 microns, and the non-photosensitive cladding has a diameter that is about 125 microns.

25. A microbead according to claim 20, wherein the photosensitive core has a diameter that is about 12 microns, and the non-photosensitive cladding has a diameter that is about 65 microns.

26. A microbead according to claim 20, wherein the photosensitive core has a diameter that is about ⅕

the diameter of the non-photosensitive cladding.

27. A microbead according to claim 20, wherein the photosensitive core is doped with Boron.

28. A microbead according to claim 20, wherein the photosensitive core is doped with excess amounts of Boron when compared to a standard telecom optical fiber.