Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
152 words
Apparatus for detecting changes in chemical or physical parameters, comprising: a sensing optical fibre including a core surrounded by a relatively sensitive cladding the absorption spectrum of which varies with changes in chemical or physical parameters when these are applied to said relatively sensitive cladding; and transmissive optical fibre means, including a core surrounded by a relatively insensitive cladding the absorption spectrum of which tends not to vary with changes in the chemical or physical parameters when these are applied to said relatively insensitive cladding, for connecting at least one end of the sensing optical fibre to a remote light source and a remote detector; the core of the sensing optical fibre having substantially the same diameter as the core of the transmissive fibre means; said relatively insensitive cladding refractive index being less than the refractive indices of the cores of both the sensing optical fibre and the transmissive optical fibre means.
Claim 2
Dependent Claim
152 words
Apparatus for detecting changes in chemical or physical parameters, comprising: a sensing optical fibre including a core surrounded by a relatively sensitive cladding the absorption spectrum of which varies with changes in chemical or physical parameters when these are applied to said relatively sensitive cladding; and transmissive optical fibre means, including a core surrounded by a relatively insensitive cladding the absorption spectrum of which tends not to vary with changes in the chemical or physical parameters when these are applied to said relatively insensitive cladding, for connecting at least one end of the sensing optical fibre to a remote light source and a remote detector; the core of the sensing optical fibre having substantially the same diameter as the core of the transmissive fibre means; said relatively insensitive cladding refractive index being less than the refractive indices of the cores of both the sensing optical fibre and the transmissive optical fibre means.
Claim 3
Dependent Claim
62 words
Apparatus as claimed in claim 1, in the configuration of a probe having a reflective sensitive end and a remote end connectable to both said light source and said detector so that light fed into the remote end is transmitted to the sensitive end, and at least a portion thereof is reflected back to the remote end for collection by the detector.
Claim 4
Dependent Claim
46 words
Apparatus as claimed in claim 2 wherein: the core of the sensing optical fibre is made reflective at one end; and the other end of said sensing optical fibre extends from the transmissive optical fibre for conveying light both to and from the sensing optical fibre.
Claim 5
Dependent Claim
93 words
Apparatus as claimed in claim 2 wherein: there are provided two sensing optical fibre portions each having an end which leads into a different transmissive fibre, these sensing optical fibre portions lying adjacent each other and joined by a reflective coupling means whereby light launched from source into the remote end of one transmissive fibre travels through that fibre, through one portion of the sensing optical fibre to be reflected into the other portion there and thence along the other transmissive fibre for detection at the remote end of said other transmissive fibre.
Claim 6
Dependent Claim
34 words
Apparatus as claimed in claim 1, wherein said sensing optical fibre is constructed and arranged to have opposite ends thereof connected to a light source and detector respectively via the transmissive optical fibre means,
Claim 7
Dependent Claim
52 words
Apparatus as claimed in claim 5 and further including: a container of fluid; wherein the sensing optical fibre is located within said container of fluid, and the end portions thereof are constructed and arranged to be connected via the transmissive optical fibre means to a light source and detector outside the container.
Claim 8
Dependent Claim
18 words
Apparatus as claimed in claim 5, wherein the sensing optical fibre is in the form of a coil.
Claim 9
Dependent Claim
25 words
Apparatus as claimed in claim 1, wherein: the relatively sensitive cladding for the sensing optical fibre comprises a chemochromic material embedded in a solid carrier.
Claim 10
Dependent Claim
29 words
Apparatus as claimed in claim 8 wherein the chemochromic material comprises at least one pH sensitive dye and wherein the solid carrier comprises a water insoluble, water swellable material.
Claim 11
Dependent Claim
28 words
Apparatus as claimed claim 1, wherein: the relatively sensitive cladding comprises a material which can quantitatively undergo an irreversible colour change when subjected to physical or chemical parameters.