An optochemical sensor for determining a measurement signal, which correlates with a concentration of an analyte of a measuring fluid, comprises: a sensor cap including a sensor spot, wherein the sensor spot contains at least one analyte-sensitive indicator dye and a state description indicator which reflects the aging state of the sensor spot; a radiation source to radiate excitation radiation onto the sensor spot and to excite a luminescence of the indicator dye; a radiation receiver to receive reception radiation emitted by the sensor spot; and a sensor circuit electrically connected to the radiation source and the radiation receiver and configured to control the radiation source and to generate, based on an intensity of luminescence and/or a phase angle of luminescence, a measurement signal representing the concentration of the analyte in the measuring fluid in contact with the sensor spot.

Embodiments include a fiber optic probe comprising an optical fiber, and a sensor component attached to the optical fiber, the sensor component including an asymmetric microlens array imprinted on a stimuli-responsive hydrogel. Embodiments further include a method of fabricating a fiber optic probe comprising depositing a stimuli-responsive hydrogel precursor solution on a substrate mold, the substrate mold including a concave asymmetric microlens array; contacting an end of an optical fiber with the stimuli-responsive hydrogel precursor solution deposited on the substrate mold; and exposing the end of the optical fiber and the stimuli-responsive hydrogel precursor solution to light to form a stimuli-responsive hydrogel sensor imprinted with a convex asymmetric microlens array and attached to the end of the optical fiber. Embodiments further include systems comprising the fiber optic probes.

Embodiments include a fiber optic probe comprising an optical fiber, and a sensor component attached to the optical fiber, the sensor component including an asymmetric microlens array imprinted on a stimuli-responsive hydrogel. Embodiments further include a method of fabricating a fiber optic probe comprising depositing a stimuli-responsive hydrogel precursor solution on a substrate mold, the substrate mold including a concave asymmetric microlens array; contacting an end of an optical fiber with the stimuli-responsive hydrogel precursor solution deposited on the substrate mold; and exposing the end of the optical fiber and the stimuli-responsive hydrogel precursor solution to light to form a stimuli-responsive hydrogel sensor imprinted with a convex asymmetric microlens array and attached to the end of the optical fiber. Embodiments further include systems comprising the fiber optic probes.

There is provided a method of calibrating a sensor comprising a luminescent compound having a luminescence that depends on the concentration of an analyte, and a detector configured to detect light emitted by the luminescent compound, the method comprising providing a component comprising the luminescent compound in a package that maintains exposure of the luminescent compound to the analyte at a known first concentration, assembling the component into the sensor and measuring a first value of a characteristic of the luminescence of the luminescent compound while exposed to the analyte at the first concentration, measuring a second value of the characteristic of the luminescence of the luminescent compound while exposed to the analyte at a known second concentration different from the first concentration, and determining parameters representing the dependence of the characteristic of the luminescence on concentration of the analyte using the first value and the second value.

The present disclosure relates to an optical sensor having a light source that emits light on a sensor layer, wherein the sensor layer can be brought into contact with a medium, wherein the first sensor layer emits emission light as a function of the incident light and a concentration of a measured value of the medium; a receiver, which receives the emission light; a first light guide, which conducts light from the light source onto a first region of the sensor layer and conducts emission light from the first region of the sensor layer to the receiver; and a second light guide independent of the first light guide which conducts light from the light source onto a second region of the first sensor layer and conducts emission light from the second region of the sensor layer to the receiver.

An optical fiber having metallic micro/nano-structure on end-facet, and a fabrication method and an application method thereof. The metallic micro/nano-structure is a micro-nano structure resonance cavity on a metallic film, and generates surface plasmon resonance when an optical fiber guided wave is incident. In the fabrication method according to the present invention, the metallic micro/nano-structure on the surface of the substrate is aligned with and is adhered to the end-facet of the optical fiber, and is removed for transferring to the end-facet of the optical fiber. In the application method according to the present invention, the end-facet of the optical fiber is contacted with or moved towards a medium, and a refractive index of the medium is measured by measuring reflection of an optical fiber guided wave by the metallic micro/nano-structure resonance cavity.

A method for manufacturing an ion sensor, especially a pH measurement sensor, based on optical fibre, including the following steps: cleaving the optical fibre, with free hydroxyl groups appearing on the cleavage surface, grafting a layer of trifunctional silane directly on free hydroxyl groups having appeared accordingly on the cleavage surface of the optical fibre, without a prior external activation step, grafting a layer of difunctional silane on the cleavage surface of the optical fibre, and grafting a fluorescent dye.

The invention relates to a method for detecting a local change in refractive index of a dielectric medium located on the surface of an optical sensor, said optical sensor comprising for this purpose a waveguide comprising a region, called the active region, covered with at least one metallic layer in contact with the dielectric medium, said method comprising the following steps: a) emitting a light beam at the input of the waveguide so that this light beam can be propagated, within the waveguide, according to at least N propagation modes, where N is a natural integer such that N≥2; b) measuring the intensity of at least one zone of the spatial distribution of the intensity of the light beam reflected by said active region of the optical sensor; and c) detecting the local change in the refractive index of the dielectric medium by means of a database supplying the link between the intensity of said at least one zone of the spatial distribution of the intensity of the light beam reflected by the active region of the optical sensor and a change in refractive index of a reference medium.

The present application discloses a sensor for determining a measurand correlated with a concentration of at least one analyte belonging to the class of reactive oxygen species in a measuring fluid, the sensor including a sensor element having an indicator substance, wherein the indicator substance is oxidized into an oxidized form of the indicator substance by the at least one analyte, a means for generating a flow of current in the sensor element that causes a reduction of the oxidized form of the indicator substance and thereby regeneration of the indicator substance, an optical measuring sensor to detect measuring radiation influenced by the oxidized form of the indicator substance and to generate an electrical measuring signal using the influenced measuring radiation, and a sensor switch connected to the optical measuring sensor to receive the measuring signal and to ascertain a measured value of the measurand using the measuring signal.

Disclosed is a surface plasmon resonance sensor. The surface plasmon resonance sensor includes an optical fiber; a microfiber provided at an end of the optical fiber; and a nanostructure provided in a specific region of the microprobe. The specific region of the microprobe is present at a position separate by a predetermined distance from the end of the optical fiber, and, in the nanostructure, a conductive layer is provided at an interval of a nano size at each of both sides of an insulating layer.