Optical Sensor and Method

• US 20140254977A1
• Filed: 03/08/2013
• Published: 09/11/2014
• Est. Priority Date: 03/08/2013
• Status: Active Grant

• Current Assignee: Predrag Mikulic, Saurabh Mani Tripathi, Wojtek J. Bock
• Original Assignee: Predrag Mikulic, Saurabh Mani Tripathi, Wojtek J. Bock
• Inventors: Bock, Wojtek J., Tripathi, Saurabh Mani, Mikulic, Predrag
• Granted Patent: US 10,168,471 B2
• Time in Patent Office: Days
• US Class Current: 385/12
• CPC Class Codes: G01D 5/35316 using a Bragg gratings
• CPC Class Codes: G01N 21/7743 the reagent-coated grating coupling light in or out of the waveguide
• CPC Class Codes: G02B 6/02085 characterised by the grating profile, e.g. chirped, apodised, tilted, helical

Abstract

An optical sensor has a waveguide having a core, a cladding having an outer surface and a long period fiber grating. The core, the cladding and the long period fiber grating collectively provide at least two resonant wavelengths. The optical sensor also has binding sites on the outer surface of the cladding for binding to elements to be detected to the outer surface of the cladding. The cladding may be thinned down to a thickness sufficiently low produce the resonant wavelengths. The binding sites include agents for binding to the elements to be detected with the agents being covalently bonded to the surface of the cladding. Example binding sites can include bacteriophages for detecting E. coli bacteria, Palladium for detecting hydrogen, or synthetic DNA for detecting viruses of certain molecules for example.

Claims

1. An optical sensor comprising:

a waveguide having a core, a cladding having an outer surface and a long period fiber grating, the core, the cladding and the long period fiber grating collectively providing at least one split resonance; and

binding sites on the outer surface of the cladding for binding to elements to be detected to the outer surface of the cladding.

2. An optical sensor according to claim 1 wherein the cladding is thinned down to a thickness sufficiently low produce the at least one split resonance.

4. An optical sensor according to anyone on claim 1 to 3 wherein the binding sites comprise agents for binding to the elements to be detected, the agents being covalently bonded to the surface of the cladding.

5. An optical sensor according to anyone of claim 1 to 4 wherein the binding sites comprise a biophage.

6. An optical sensor according to anyone of claim 1 to 4 wherein the binding sites comprise a bacteriophage.

7. An optical sensor according to anyone of claim 1 to 4 wherein the binding sites comprise Palladium.

8. An optical sensor according to anyone of claim 1 to 4 wherein the binding sites comprise synthetic DNA.

9. An optical sensor according to anyone of claim 1 to 4 wherein the binding sites comprise at least two different types of binding sites capable of binding to different types of elements.

10. An optical sensor comprising:

a waveguide having a core, a cladding having an outer surface and a long period fiber grating, the core, the cladding and the long period fiber grating collectively providing at least one resonant wavelength; and

binding sites covalently bonded on the outer surface of the cladding for binding to elements to be detected to the outer surface of the cladding.

11. A method of fabricating an optical sensor having a waveguide with a core, cladding having an outer surface and a grating, the method comprising:

etching the cladding at the outer surface to thin the cladding down to a thickness sufficiently low to produce at least two resonant wavelengths.

12. A method according to claim 11 comprising:

covalently bonding binding sites to the outer surface of the cladding for allowing elements to be detected to bind to the outer surface of the cladding.

13. A method according to claim 11 wherein the grating is a long period fiber grating.

14. A method of fabricating an optical sensor having a waveguide with a core, cladding having an outer surface and a grating, the method comprising:

covalently bonding binding sites to the outer surface of the cladding for allowing elements to be detected to bind to the outer surface of the cladding.

15. A method according to claim 14 wherein the grating is a long period fiber grating.