113 results about "Waveguide sensor" patented technology

According to embodiments of the present invention, a distributed pressure and shear stress sensor includes a flexible substrate, such as PDMS, with a waveguide formed thereon. Along the waveguide path are several Bragg gratings. Each Bragg grating has a characteristic Bragg wavelength that shifts in response to an applied load due to elongation/compression of the grating. The wavelength shifts are monitored using a single input and a single output for the waveguide to determine the amount of applied pressure on the gratings. To measure shear stress, two flexible substrates with the waveguide and Bragg gratings are placed on top of each other such that the waveguides and gratings are perpendicular to each other. To fabricate the distributive pressure and shear sensor, a unique micro-molding technique is used wherein gratings are stamped into PDMS, for example.

The present invention is directed to a waveguide sensor as well as to an evanescent field induced evanescent field induced sensor system for use in diagnostic housing and an integrated waveguide sensor comprising: a waveguide layer,—capture compounds applied on the upper surface of said waveguide layer for 5 specific bonding to target substances,—a cladding layer surface of said waveguide layer,—a filter which is transmitting for luminescent radiation while absorbs and/or reflects radiation of excitation radiation, wherein the filter is arranged below the lower 10 surface of said cladding layer, at least one detector for sensing luminescent radiation, wherein the detector is arranged below the lower surface of said filter, a substrate that is connected with the detector and comprises the electrical interface of said detector; wherein 15 between the upper surface of the waveguide layer and along at least a lower surface section of the housing a channel is formed for receiving a fluidic probe; and the luminescent radiation is generated by luminescent tag bound to target substances as a result of their excitation by the evanescent field. This provides an improved sensitivity of the evanescent field induced sensor 20 system.

A side-hole optical cane for measuring pressure and/or temperature is disclosed. The side-hole cane has a light guiding core containing a sensor and a cladding containing symmetrical side-holes extending substantially parallel to the core. The side-holes cause an asymmetric stress across the core of the sensor creating a birefringent sensor. The sensor, preferably a Bragg grating, reflects a first and second wavelength each associated with orthogonal polarization vectors, wherein the degree of separation between the two is proportional to the pressure exerted on the core. The side-hole cane structure self-compensates and is insensitive to temperature variations when used as a pressure sensor, because temperature induces an equal shift in both the first and second wavelengths. Furthermore, the magnitude of these shifts can be monitored to deduce temperature, hence providing the side-hole cane additional temperature sensing capability that is unaffected by pressure. Additionally, the side-hole cane can be used to measure a differential pressure between a first pressure ported to the side-holes and a second external pressure.

Methods and apparatuses are provided that greatly expand the utility of conventional hollow waveguide-based sensors via either straight, substrate-integrated channels or via meandering (e.g., circuitous, curved or folded optical paths) waveguide sensor designs. Full- or hybrid-integration of the meandering hollow waveguide with light source, detector, and light-guiding optics facilitates compact yet high-performance gas/vapor and/or liquid sensors of the substrate-integrated hollow waveguide sensor.

The invention provides an integrated optical waveguide sensor module (200) with reduced signal modulation and increased sensitivity. An optical waveguide sensor module (200) comprises an optically transparent substrate (210) having a first and a second interface and an optical waveguide film (220) disposed on the substrate (210) with the first interface (225) therebetween, wherein the film (220) comprises at least one grating pad (235) that is optically coupled therewith. The substrate (210) and the optical waveguide film (220) are configured to reduce parasitic interference within the substrate.

A waveguide magneto-optic sensor provides a signal indicative of the value and/or direction of a detected magnetic field by a spectral shift of the characteristic resonant spectral feature of the sensor is disclosed. The sensor does not suffer from vibrations, fiber bending or other light intensity noise and provides an absolute self-referencing signal. The sensor elements can easily be coupled to optical fibers and read with scanning spectrometers or scanning lasers calibrated against NIST-traceable gas absorption standards.

An optical waveguide sensor for glucose measurement comprises a substrate, a first optical waveguide layer formed on a surface of the substrate, an entrance grating and an exit grating which are formed contacting with the first optical waveguide layer and being spaced from each other, a second optical waveguide layer located between the entrance grating and the exit grating while being in contact with the first optical waveguide layer, the second optical waveguide layer having a higher refractive index that that of the first optical waveguide layer, and a functioning layer containing an enzyme and a coloring reagent which is formed on the second optical waveguide layer.

A detection system for a first specific material is provided by which an interferometer, having a reference waveguide segment and a test waveguide segment, is enhanced. The test waveguide segment carries a second capture material for specifically capturing said first specific material that may be present in a fluid specimen. Capture of the first specific material is detected by an interference pattern produced by combining coherent light beams passing through the waveguide segments. To enhance by orders of magnitude the detection limits of the test, the waveguide segments are subjected to an alternating or pulsed electrical or magnetic fields. This same signal is fed to a lock-in amplifier that is associated with computational means by which the interference pattern is interpreted. The invention further includes a waveguide system in which capture of the first specific material is detected by fluorescence. Detection of the fluorescent signal is enhanced relative to noise by subjecting the waveguide segment to alternating or pulsed electrical or magnetic signal.

A waveguide sensor capable of direct, real-time detection and monitoring of analytes in the vicinity of the waveguide surface without requiring the tagging or labeling of the analyte, is described. Analytic and numerical calculations have predicted that by locally detecting either changes in the evanescent field or changes in the light coupled out of the waveguide as a result of the presence of the analyte, high detection sensitivity will be able to be achieved.

An optical-waveguide sensor chip includes an optical waveguide having a first substance immobilized on the surface thereof, the first substance being specifically reactive with an analyte substance, and fine particles dispersed on the optical waveguide and having a second substance immobilized on the surface thereof, the second substance being specifically reactive with the analyte substance.

The invention discloses an optical waveguide sensor and preparation methods thereof. The optical waveguide sensor comprises a structure as follows: an optical waveguide substrate medium consists of heat resisting optical materials and is provided with linear optical waveguides, and in which an optical grating structure is arranged in the linear optical waveguides. The invention further discloses many preparation methods of the structure. Another waveguide sensor comprises a structure as follows: the optical waveguide substrate medium consists of heat resisting optical materials and is provided with linear optical waveguides, and an optical grating structure is further arranged on the surface of the optical waveguide substrate. The invention further discloses many preparation methods of the structure. Because the optical waveguide apparatus has a simple module structure or a structure with few modules, the optical grating on the optical waveguide channel only has a harmonic module or few modules. When the environment temperature is changed, the refractive index of the optical waveguide material and the period of the optical waveguide grating can be changed, therefore, the change of temperature can be measured by measuring the change of wavelength of harmonic wave of the optical grating in the optical waveguide channel on the optical waveguide substrate. Due to the adoption of the laser technology and microelectronic production process, a plurality of optical waveguide grating sensing apparatuses can be further produced on a same substrate with low production cost and high efficiency.

The invention relates to the technical field of waveguide sensors. A novel Michelson interferometer for sensing measurement is designed by using the principle of waveguide nonlinear environment, and has a basic structure that two output ports of a 2*2 waveguide coupler of Mach-Zehnder interferometer are connected by waveguide, wherein the splitting ratio of the waveguide coupler is 1 to 1; or the middle part of a small section of waveguide (fiber) is directly rolled to manufacture a 2*2 waveguide coupler of which splitting ratio is 1 to 1; and the waveguide coupler is connected with another 2*2 waveguide coupler to form the Michelson interferometer. The waveguide interference sensor with low cost and same phase change and reflectivity at two reflection parts is provided with the novel Michelson interferometer structure so as to achieve the effects of improving interference contrast and improving measurement sensitivity.

Methods and apparatuses that sense physical parameters, such as pressure and strain, using optical waveguide sensors are described. A light source emits light at a predetermined wavelength along an optical waveguide having a fiber Bragg grating optical sensing element. That sensing element reflects light in accord with a sloped shape function of reflected light amplitude verses wavelength. A receiver converts the reflected light into electrical signals and an analyzer then determines a physical parameter based on changes of amplitude of the reflected light. The analyzer also maintains the wavelength of the light such that the wavelength corresponds to a slope wavelength of the shape function.

A device for use in measuring stratified fluid levels in a container is disclosed. The device has a microwave transceiver sensor head attached to a waveguide sensor rod which is enclosed by a gauge tube. The rod end tubes are comprised of sections which allow them to be assembled or disassembled in a close quarters environment. The tube has a plurality of circumferentially and longitudinally spaced slots providing for the equalization of stratified fluids within the tube. The rod is generally radially centered in the tube by the use of a plurality of spacers which reside in notches in the rod. The spacers are adapted to not penetrate the slots in the tube. The rod can be removed from the tube for cleaning without draining the tank. Additionally, once the rod is removed from the tube, a cleaner brush or scraper can be used to remove any barnacles or other debris from within the tube and the longitudinal slots in the tube.