Fiber optic which is an inherent chemical sensor
AssigneeST&E, Inc.
InventorStanley M. Klainer
Life of this patent
Estimating the term…
Abstract
A fiber optic element is used to detect the presence of chemical or biological species by measuring changes in the total internal reflection characteristics of the element produced by changes in the index of refraction of a clad or layer of a material which reacts with the chemical or biological species.
Claims34
A method of forming a chemically or biologically sensing optical fiber having a core which transmits light of a predetermined wavelength and a fiber optic clad surrounding the core and made of a material with an index of refraction less than the core and which reacts with a predetermined chemical or biological species to produce measurable changes in the transmission of light through the optical fiber in the presence of the predetermined chemical or biological species, the method comprising:
- first selecting a clad material for its reaction properties with the predetermined chemical or biological species;
- then selecting a core material which is effectively index matched to the clad to form an optical fiber;
- forming a fiber optic element from the thus-selected core and clad materials.
A chemically or biologically sensing optical fiber comprising:
- a core which transmits light of a predetermined wavelength;
- a reactive layer surrounding the core and made of a material which reacts with a predetermined chemical or biological species to produce measurable changes in the transmission of light through the optical fiber in the presence of the predetermined chemical or biological species;
- a fiber optic clad surrounding the reactive layer and which is porous to the predetermined chemical or biological species;
- wherein the reactive layer has an index of refraction greater than the core and the core has an index of refraction greater than the clad.
A chemically or biologically sensing optical fiber comprising:
- a core which transmits light of a predetermined wavelength;
- a fiber optic clad surrounding the core and made of a material with an index of refraction less than the core and which reacts with a predetermined chemical or biological species to produce measurable changes in transmission of light through the optical fiber in the presence of the predetermined chemical or biological species;
- an internal light source selected from the group consisting of phosphors and fluorophores.
A method of detecting the presence of a predetermined chemical or biological species comprising:
- forming a chemically or biologically sensing optical fiber having a core which transmits light of a predetermined wavelength and a fiber optic clad surrounding the core and made of a material with an index of refraction less than the core and which reacts with a predetermined chemical or biological species to produce measurable changes in the transmission of light through the optical fiber in the presence of the predetermined chemical or biological species by the steps of first selecting a clad material for its reaction properties with the predetermined chemical or biological species, (b) then selecting a core material which is effectively index matched to the clad to form an optical fiber, (c) forming a fiber optic element from the thus-selected core and clad materials;
- transmitting a light beam of the predetermined wavelength into the sensing optical fiber;
- detecting changes in the transmission of the light beam through the sensing optical fiber caused by reaction of the clad with the predetermined chemical or biological species.
A chemically sensing optical fiber comprising:
- a clad selected from the group consisting of cobaltous chloride, iodine, and barium chloride;
- a core having a refractive index greater than the clad and selected to effectively match the clad.
A method of detecting the presence of a predetermined chemical or biological species comprising:
- forming a chemically or biologically sensing optical fiber having a core which transmits light of a predetermined wavelength, a reactive layer surrounding the core and made of a material which reacts with a predetermined chemical or biological species to produce measurable changes in the transmission of light through the optical fiber in the presence of the predetermined chemical or biological species, and a fiber optic clad surrounding the reactive layer and which is porous to the predetermined chemical or biological species, wherein the reactive layer has an index of refraction greater than the core and the core has an index of refraction greater than the clad;
- transmitting a light beam of the predetermined wavelength into the sensing optical fiber;
- detecting changes in the transmission of the light beam through the sensing optical fiber caused by reaction of the clad with the predetermined chemical or biological species.
Dependencies are inferred from the claim text.