Abstract: The present invention provides a plurality of samples, each of which includes particles of a predetermined particle dimension, within narrow predetermined limits, dispersed in a carrier at a predetermined particle concentration. The predetermined particle dimension and the predetermined particle concentration are the same for each sample. However, advantageously, each sample has a different predetermined ratio of a value of an optical property of the particles to a value of the same optical property of the carrier. The present invention also provides a method for selecting a target sample from the plurality of samples to assess the measurement accuracy or the detection sensitivity of an optical particle analyzer as the predetermined ratio approaches 1.

Abstract: System and method for fluorescent light excitation and detection from samples to enhance the numerical aperture and/or reduce the cross-talk of the fluorescent light.

Abstract: A Method and apparatus to accurately measure and display various properties of hydrocarbons and petroleum factions for a small volume of sample in a short period of time in one test with less cost and energy for the analysis by the method of light refection. The refraction of light through the sample is measured and compared to the refraction f the light through vacuum by the apparatus. The method of the invention comprises a property estimation from the apparatus to output a property estimate value. The property estimation means is equipped with a property estimation model for evaluating the property estimate value outputted from the property estimation model. The method is incorporated into standard or otherwise any refractive index test apparatus or refractometer to provide accurate measure of the thermodynamic and transport properties of pure hydrocarbons and undefined multicomponent mixtures such as petroleum factions.

Abstract: A chemical sensor based on an indicator dye wherein a light transmissive element containing the indicator dye is made of a hygroscopic polymer. The polymer may be, for example, a polyimide or PMMA or other polymer. In an alternative embodiment the light transmissive element is doped with metal nanocolloidal particles. One embodiment may include a reference photodiode and differential amplifier to compensate for the fluctuations of the intensity of the light source. The light source may be pulse modulated. The sensor may include calibration means comprising a reference sample of the chemical to be detected and a precision delivery means. A method of fabricating the polymer and metal nanocolloid is disclosed wherein the nanocolloid is produced by generating a pulsed laser plasma in a suspension of metal particles and an organic solvent and adding the resulting solvent colloid to a solution containing the polymer.

Abstract: An objective of the present invention is to provide an optical fiber sensor which has a simple configuration to enable sensitively measuring a refractive index of a measurement medium in a wide range of refractive indexes. An optical fiber sensor according to the present invention includes; an optical fiber having a core in which a short-period gratings are formed and a cladding, the optical fiber being made so that transmission loss occurs due to cladding-propagation-mode leakage at its cladding portion where the short-period gratings are formed; a light source from which light having a wavelength range of the cladding propagation mode is emitted; and a light receiving unit for receiving transmission or reflection light having passed through the cladding at the position where the short-period gratings are formed.

Abstract: An optical refractometer is provided for measuring the refractive index of a liquid. Such a refractometer includes a first optical block having a transparent material whereto is secured a light source, a second optical block having a transparent material whereto is secured a position sensor. The optical blocks are arranged on either side of a conduit wherein the liquid flows.

Abstract: There is described a method for determining a quantitative parameter of a compound in an analysis sample, comprising: providing a scattering medium in physical contact with the analysis sample, the scattering medium having at least one layer, an index of refraction of the scattering medium being superior to an index of refraction of the analysis sample; propagating, in the scattering medium, an incident beam of light having a wavelength substantially corresponding to an absorption wavelength of the compound such that an evanescent wave is generated at an interface between the scattering medium and the analysis sample; taking n intensity measurements of a reflected beam of light for the analysis sample, n being superior to one; and determining the quantitative parameter of the compound using the n intensity measurements for the analysis sample.

Abstract: Methods of measuring the refractive index profile of a transparent cylindrical object, such as a fiber preform, are disclosed. The methods include transmitting light rays through the cylindrical object in a direction transverse to the central axis at different heights and measuring the deflection angles to define a measured deflection function ?m. The methods include numerically fitting a target deflection function ?t to the measured deflection function ?m within a first object region that does not include the object's outer edge. The fit is conducted by varying the yet unknown parameters of the refractive index profile that define the target deflection function to obtain an estimated refractive index profile ?*i(r) over a second object region equal to or greater in size than the first object region. For cylindrical objects having at least one refractive index continuity, the method is applied to the different regions defined by the at least one discontinuity.

Abstract: Systems and methods for identifying refractive-index fluctuations of a target are described in this application. One embodiment includes identifying one or more properties of emergent light, the emergent light to be emergent from a target, and determining refractive-index fluctuations of the target based on the one or more properties of the emergent light. The determining refractive-index fluctuations further comprises determining one or more of the variance of the refractive-index fluctuations and the spatial correlation length of the refractive-index fluctuations. The determining refractive-index fluctuations further comprises determining one or more of the variance of the refractive-index fluctuations and the spatial correlation length of the refractive-index fluctuations.

Abstract: A system for testing a reflective display device includes a testing apparatus and a computer. The testing apparatus includes one or more light emitters, one or more light detectors, an analog-to-digital converter (ADC) module, and a microcontroller unit (MCU). The light emitters are for projecting light onto a reflective display device located on the testing apparatus. The light detectors are for sensing reflected light from the reflective display device, and generating electricity according to a luminance of the reflected light. The ADC module is for receiving the electrical signals from the light detectors, and producing a digital output according to voltages of the electrical signals. The MCU is configured for reading the digital output of the ADC module. The computer is for processing the digital output and displaying results after processing.

Abstract: A sample can be illuminated for analysis using apparatus including a light source, a planar waveguide, and a refractive volume. The light source provides light along a propagation vector. The planar waveguide is oriented such that the propagation vector is perpendicular to the normal vector of the planar waveguide and offset from the planar waveguide in a direction parallel to the normal vector of the planar waveguide. The refractive volume is positioned proximate to the planar waveguide and can optically coupling light provided by the light source to the planar waveguide.

Abstract: Method and apparatus for precision non-destructive non-contact control of super small differences of pressure, which is used for non-destructive control of tightness of various products regardless of the method of sealing and the state of the internal volume of products, with the apparatus consisting of a body of the control unit of the device, working and control units, sensitive membrane, transparent window of the control unit, connecting pipes of the control and working chambers, electronic speckle interferometer, the base that is isolated from the vibration, and the electronic processing unit for monitoring results and presenting results on the display. The bending of the membrane characterizes the quality of sealing of the investigated object and is determined by the laser method of non-contact electronic speckle interferometry.

Abstract: An inspection instrument includes main unit, Brix testing unit, weight measurement unit, display unit, control unit, and label printer; both of Brix and weight of an object pending test are tested and measured at the same time by the Brix testing unit and the weight measurement unit; resultant data are directly displayed on the inspection instrument by the display unit; data are directly printed on a label; and the label is outputted to be directly attached to the fruit.

Abstract: The present invention relates to a thermally compensated optical sensing system for identifying various types of liquid fuels and/or the ratio in liquid fuel mixtures on real time. In this system, an optical fiber is used as a light guide and a sensor device for determining the refractive index of liquid fuels through the principle of reflectivity. Starting from a light source, light is transmitted interiorly of the optical fiber to the test probe which is in contact with the fuel. The optical signal resulting from the interaction between light and fuel is a function of refractive indexes of the optical fiber and the fuel, the wavelength of light used, and the fuel temperature. The system proposed herein relates to the use of this optical system in liquid fuels by using optical fibers having suitable refractive indexes as a function of the fuel type and/or fuel mixture being analyzed, allowing the sensitivity of the optical system to be optimized according to application requirements.

Abstract: A method for measuring the optical properties of multifocal ophthalmic lenses. Collimated light is passed through an ophthalmic lens and onto an array of lenslets. Light exiting the array of lenslets is detected by a sensor. Blurred spots and/or double spots may represent diffractive zones of the wavefront. A centroid of the spot or a brighter of two spots may be used to determine the lateral position of the spot. Theoretical calculations, laboratory measurements, clinical measurements and experimental image spots may be generated, compared and cross-checked to determine a monofocal equivalent lens. A Modulation Transfer Function (MTF) may be used to evaluate and compare a diffractive lens and a monofocal equivalent lens.

Abstract: An exemplary refractive-index sensor includes a photonic crystal microcavity structure, a light source, and a detector. The photonic crystal microcavity structure includes a photonic crystal layer having first holes and a second hole. The first holes are arranged in a pattern of staggered parallel rows. The second hole is located at an approximate center point of the middle row of the pattern rather than a first hole. A diameter of the second hole is less than that of each of the first holes. Some of the first holes disposed at each of opposite ends of a diagonal row having the second hole are omitted to define an input waveguide and an output waveguide. The light source is adjacent to the input waveguide. The detector is adjacent to the output waveguide.

Abstract: A microscope for total internal reflection microscopy. The microscope includes at least one light source configured to provide an illumination light to an illumination beam path for an evanescent illumination of a specimen so as to reflect the illumination light at an interface to the specimen or a specimen cover so as to return reflection light into the illumination beam path, an objective through which the illumination light and detection light are directable, a detection device, and a coupling device. The coupling device includes a mirror disposed in the illumination beam path. The mirror has a reflecting surface and a hole, the hole being configured to pass the illumination light there through so as to couple the illumination light into the illumination beam path.

Abstract: A refractive index distribution measurement method includes the steps of measuring a first transmission wavefront of a test object by introducing reference light to the test object immersed in a first medium having a first refractive index lower than that of the test object by 0.01 or more, measuring a second transmission wavefront of the test object by introducing the reference light to the test object immersed in a second medium having a second refractive index lower than that of the test object by 0.01 or more and different from the first refractive index, and obtaining a refractive index distribution of the test object based on a measurement result of the first transmission wavefront and a measurement result of the second transmission wavefront.

Abstract: An apparatus and method for optically detecting the presence of an analyte in a solution is presented. An embodiment comprises a waveguide resonator that is optically coupled to a fluid in a fluidic conduit so that the resonant wavelength of the waveguide resonator is based on the refractive index of the fluid.

Abstract: An improved refractometer for automatically determining the refractive index of a test subject by using principles embodied in Brewster's Angle, the refractometer comprising a light source, a light detector, a subject mount for securing the test subject to the device, a positioning device to orient the light source and light detector to the subject such that the angles of the light source and light detector to the subject are substantially identical, a data gathering device to automatically retrieve relevant data regarding the angles of the light source and light detector to the subject and the light intensity of the reflected light, and a computational device to process the data using algorithms taking into account the principles embodied in Brewster's Angle and/or Fresnel Equations in order to arrive at the refractive index of the test subject.

Abstract: A total reflection illuminated sensor chip is employed to detect a target substance, by: supplying a sample containing the target substance onto a detecting portion formed on a surface of a dielectric prism, irradiating a measuring light beam onto the interface between the prism and the detecting portion through a transmitting surface of the prism such that conditions for total reflection are satisfied, and utilizing evanescent waves generated at the detecting portion. The sensor chip includes a protective member for protecting the transmitting surface. The protective member is provided a predetermined distance away from the transmitting surface to form a transmitting space, which is open at least toward the downward direction. The sensor chip is configured such that the interface can be irradiated by the measuring light beam that enters the transmitting space from below the transmitting space and passes through the transmitting surface.

Abstract: The invention provides an apparatus for measuring the differential refractive index for liquid chromatography which greatly improves the sensitivity while having quick responsiveness to refractive index difference of sample liquid, as well as a differential refractive index detector and a measurement method for a differential refractive index using the same. The apparatus for measuring a differential refractive index having a flow cell deflecting a measurement beam in accordance with the refractive index difference between a reference liquid and a sample liquid for measuring the change of the deflection angle on the basis of the refractive index difference of the measurement beam transmitted between the reference liquid and the sample liquid, wherein the flow cell comprises three independent chambers including a first chamber, a second chamber adjacent to the first chamber and a third chamber adjacent to the second chamber.

Abstract: The invention concerns an equipment for monitoring an immersion lithography device provided with a main light source and a projection optics for printing images on a wafer. The propagating medium extending from the projection optics to the wafer consists of a liquid (3). The equipment comprises: a chamber (51) for receiving at least part of said liquid (3), a diffraction grating (50) immersed in the chamber; a secondary light source (271) for emitting a secondary incident beam (20) towards the grating so as to obtain a diffracted beam; angle measuring members (57) capable of measuring at least one diffraction angle corresponding to a maximum intensity of an order of diffraction of the beam diffracted by the grating (500), and computing means (505) for calculating an estimate of a physical quantity concerning the refractive index of the liquid.

Abstract: A method for measuring the refractive index of a material with Bragg gratings includes the emission of a collimated radiation beam (9) from a radiation source (4) with a large spectrum and orientation thereof along a direction normal to the material (2) to be examined, the propagation of the collimated radiation beam (9) entering the material (2), then a Bragg diffraction grating (3) that is obliquely placed to the direction of the collimated radiation beam (9), and again the material (2), the subjection to spectral analysis of the collimated radiation beam exiting the material (2), the grating (3) producing a minimum in the spectrum subjected to the spectral analysis in accordance with Bragg's law, and the calculation of the refractive index of the material (2) from the measure of the wavelength corresponding to the minimum in thus spectrum. A relevant apparatus is described.

Abstract: A multi-channel swept wavelength optical interrogation system and a method are described herein that enable the interrogation of one or more biosensors which for example could be located within the wells of a microplate. In one embodiment, the optical interrogation system comprises: (a) a tunable laser that emits an optical beam which has a predetermined sequence of distinct wavelengths over a predetermined time period; (b) a distribution unit that splits the optical beam into a plurality of interrogation beams; (c) an array of optical interrogation units that receive and direct the interrogation beams towards an array of biosensors; (d) the array of optical interrogation units receive a plurality of reflected interrogation beams from the array of biosensors; (e) a data processing device that receives and processes information associated with the reflected interrogation beams to determine for example whether or not there was a biochemical interaction on anyone of the biosensors.

Abstract: Disclosed is a method and apparatus for determining the birefringence autocorrelation length of a fiber in a non-destructive manner. The PMD of an optical fiber is measured over a first optical spectrum. A Faraday rotation angle is measured over a second optical spectrum. The birefringence autocorrelation length is determined from the measuring of the PMD and the Faraday rotation angle.

Abstract: A swept-angle SPR measurement system deflects an optical beam over a range of deflection angles according to a control signal and maps the deflected beam to a target within a range of incidence angles that corresponds to the range of deflection angles.

Abstract: Systems and methods for identifying refractive-index fluctuations of a target are described in this application. One embodiment includes identifying one or more properties of emergent light, the emergent light to be emergent from a target, and determining refractive-index fluctuations of the target based on the one or more properties of the emergent light. The determining refractive-index fluctuations further comprises determining one or more of the variance of the refractive-index fluctuations and the spatial correlation length of the refractive-index fluctuations. The determining refractive-index fluctuations further comprises determining one or more of the variance of the refractive-index fluctuations and the spatial correlation length of the refractive-index fluctuations.

Abstract: Apparatus, methods, and systems provide emitting and negatively-refractive focusing of electromagnetic energy. In some approaches the negatively-refractive focusing includes negatively-refractive focusing from an interior field region with an axial magnification substantially greaters than one. In some approaches the negatively-refractive focusing includes negatively-refractive focusing with a transformation medium, where the transformation medium may include an artificially-structured material such as a metamaterial.

Abstract: An assay technique for label-free, highly parallel, qualitative and quantitative detection of specific cell populations in a sample and for assessing cell functional status, cell-cell interactions and cellular responses to drugs, environmental toxins, bacteria, viruses and other factors that may affect cell function.

Abstract: An optical element for resonating and reflecting incident light having a wavelength includes a periodic structure formed of protrusions and recessions. A period of the periodic structure is equal to or less than the wavelength of the incident light. The incident light having the wavelength is resonated and reflected by a resonance caused between the incident light and the protrusions and recessions. Widths of the protrusions are spatially changed.

Abstract: An apparatus for detecting a property of fuel detects the property of fuel at the time of fuel supply. A measuring chamber member is provided to a fuel tank. The greater portion of fuel supplied from a fuel supply nozzle falls down from a fuel supply aperture via a flow outlet into the fuel tank. However, a part of the fuel remains in a measuring space defined between a portion below the flow outlet and a bottom portion. A fuel property detection sensor is fitted to a main body so as to oppose the measuring space. When application of a cap to the fuel supply aperture has been detected by a fuel supply cap sensor, if increase of the remaining fuel amount has been detected by a remaining fuel amount sensor, or if the engine is started, a controller measures the property of the fuel with the fuel property detection sensor.

Abstract: Apparatus, methods, and systems provide negatively-refractive focusing and sensing of electromagnetic energy. In some approaches the negatively-refractive focusing includes providing an interior focusing region with an axial magnification substantially greater than one. In some approaches the negatively-refractive focusing includes negatively-refractive focusing with a transformation medium, where the transformation medium may include an artificially-structured material such as a metamaterial.

Abstract: Apparatus, methods, and systems provide negatively-refractive focusing and sensing of electromagnetic energy. In some approaches the negatively-refractive focusing includes providing an interior focusing region with an axial magnification substantially less than one. In some approaches the negatively-refractive focusing includes negatively-refractive focusing with a transformation medium, where the transformation medium may include an artificially-structured material such as a metamaterial.

Abstract: The present invention describes (bio)chemo-functional waveguide grating structures consisting of at least one (bio)chemo-functional waveguide grating structure unit or at least one (bio)chemo-functional sensor location with beam guidance permitting light beam separation, as well as detection methods for parallel analysis which are marking-free or based on marking.

Abstract: The device for detecting changes in the refractive index of a dielectric medium comprises: at least one metallic layer (300) ready to be placed in contact with the dielectric medium (200); at least one light source (20) configured to direct transversal magnetic (TM) polarized light towards such metallic layer, so that the light is reflected on such metallic layer; coupling means (10); and at least one detector (31) configured to receive light reflected by the metallic layer and to detect at least one feature of such light. According to the invention, the metallic layer contains a ferromagnetic material. The invention also relates to a method.

Abstract: A critical wavelength refractometer is provided. A broadband light source (413) is optically coupled to a sensor (401), the sensor having at least one sensing surface (407). As the light from the broadband light source passes through the sensor, it undergoes multiple internal reflections against the sensing surface. Due to the index of refraction of the material in contact with the sensing surface, a portion of the light passing through the sensor is reflected while a second portion of the light is transmitted through the sensing surface and into the material. A detector (421) coupled to the sensor measures the spectral intensity of the light that passes completely through the sensor after having undergone the multiple internal reflections against the sensing surface. A microprocessor (423) coupled to the detector determines the critical wavelength based on the spectral intensity measurement, thereby allowing the index of refraction of the material to be determined.

Abstract: A refractometer is disclosed having a light source and an optical window to be positioned in a process liquid. A beam of rays is directed from the light source to an interface (RP) between the process liquid and the optical window and leading back part of the beam of rays refracted from the interface to the inside of the optical window. An image formed in the above manner is observed. The beam of rays from the light source is directed to the interface (RP) between the process liquid and the optical window from the side of the process liquid and in the direction of the interface.

Abstract: An exposure apparatus including a projection optical system for projecting a pattern of a reticle onto a plate to be exposed, via a liquid that is filled in a space between the projection optical system and the plate, a supply pipe for supplying the liquid to the space between a final surface in the projection optical system and the plate, a recovery pipe for recovering the liquid from the space between the final surface in the projection optical system and the plate, and a measuring apparatus for measuring a refractive index of the liquid. The measuring apparatus includes (i) a cell for accommodating the liquid and transmitting light, wherein the cell is connected to one of the supply pipe and the recovery pipe, and (ii) a detector for detecting an incident position of the light refracted by the liquid in the cell.

Abstract: Device for measuring at least one of diffusion, absorption and refraction of a sample, having a radiation source, at least one receiving element, an optical imaging element and a protection element, the radiation source and the receiving element being arranged on the sensor side of the optical imaging element, the protection element being arranged on the sample side of the imaging element and adjacent to the imaging element and the radiation source. A refraction radiation source and a refraction receiver are arranged on the sensor side of the imaging element and arranged relative to the imaging element so that the refraction radiation of the sample specularly reflected by the sample side interface of the protection element can essentially be received by the refraction receiver and the radiation specularly reflected by the imaging element side interface of the protection element essentially cannot be received by the refraction receiver.

Abstract: A system for measuring light absorption levels includes a light source providing a light beam and a container for a liquid. The container includes an opening to provide access to the liquid. A prism is disposed over the opening and is operable to direct at least a first portion of the light beam toward the opening to the liquid such that the at least a portion of the first portion of the light beam is reflected back from the liquid forming an attenuated beam. A detector is operable to measure at least one of a portion of the attenuated beam and a second portion of the light beam. The detector is operable to produce at least one of a liquid measurement signal and a reference signal. A device is operable to compute a ratio of the liquid measurement signal to the reference signal to determine a signal ratio.

Abstract: An electric field sensor is obtained by directly forming an electrooptical film of Fabry-Perot resonator structure on a polished surface at a tip of an optical fiber by an aerosol deposition method.

Abstract: We describe a fuel monitoring system, comprising: an evanescent wave fuel sensor for monitoring said fuel, the sensor comprising a light source and a transducer for providing an electrical signal in response to light from said light source, and having a light path between said light source and said transducer including an evanescent wave sensing region; and a processor coupled to said fuel sensor, for converting said electrical signal from said transducer into a signal characterising said monitored fuel; and an output coupled to said processor, for outputting a signal responsive to said fuel characterising signal. We further describe apparatus for jointly determining depth of fluid in a tank and characterising the fluid according to depth, and a fluid storage tank having a three dimensional structure for containing fluid, and a three-dimensional array of fibre-optic sensors integrated into said tank structure. Embodiments may use cavity ring-down spectroscopy.

Abstract: There is provided a sensing chip capable of measuring a refractive index by utilizing a long-range surface plasmon polariton, accurately measuring an accumulative refractive index in a wide range, and more easily enabling sealing for measurement. The present invention relates to the sensing chip which has a thin metal film or a strip-like metal grown on an underlayer, and has a dielectric that limits a refractive index and a dielectric buffer layer on an upper surface and a lower surface of the thin metal film or the strip-like metal. The dielectric buffer layer is attached onto the thin metal film or the strip-like metal. The thin metal film or the strip-like metal and the buffer layer are sandwiched between two dielectric layers. A hole is made in a surface of the upper dielectric layer to serve as a measurement groove.

Abstract: A method of recovering and recycling solvents, comprising, during printing or coating of solvent-recoverable and recyclable printing ink composition comprising solvents, a step of recovering the solvents vaporized in a solvent recovery apparatus, a step of separating the solvents obtained into one or more single solvents and/or one or more azeotropic compositions of two or more solvents by multi-stage distillation, and a step of recycling them as a printing ink raw material and/or dilution solvent raw material.

Abstract: In optical measurement utilizing total reflection, various types of measurement are selectively performed. The invention provides an optical measurement apparatus using total reflection, including a light source, a measurement optical system, and a light detector. The measurement optical system is an infinity-corrected positive lens formed of an optical member having a planar surface orthogonal to an optical axis of the measurement optical system at a front focal position. One side of the optical axis of the measurement optical system is used as a projection optical system for radiating measurement light onto a specimen, and another side is used as a photometric optical system for acquiring reflected light from the specimen.

Abstract: The invention provides compositions and methods for detection of interaction of molecules.

Abstract: A swept-angle SPR measurement system deflects an optical beam over a range of deflection angles according to a control signal and maps the deflected beam to a target within a range of incidence angles that corresponds to the range of deflection angles.

Abstract: An exemplary refractive-index sensor includes a photonic crystal microcavity structure, a light source, and a detector. The photonic crystal microcavity structure includes a photonic crystal layer having first holes and a second hole defined therein. The first holes are arranged in a regular pattern of staggered parallel rows. The second hole is at an approximate center of the regular pattern, instead of a first hole. A diameter of the second hole is different from that of the first holes. The first holes at each of opposite ends of the row having the second hole are omitted, thereby defining an input waveguide and an output waveguide. The light source is adjacent to the input waveguide. The detector is adjacent to the output waveguide.

Abstract: A method for fabricating a tunable Fabry-Perot cavity comprises etching a substrate to form two reflectors separated by an air gap and an electrostatic mechanism. One of the two reflectors is mobile and connected to the electrostatic mechanism. Therefore, operation of the electrostatic mechanism moves the mobile reflector to change the thickness of the air gap and thereby tune the Fabry-Perot cavity. A tunable Fabry-Perot cavity fabricated with the above method comprises: a substrate; two reflectors formed in the substrate and separated by an air gap having a thickness, wherein one of the two reflectors is mobile; and an electrostatic mechanism formed in the substrate and connected to the mobile reflector. The mobile reflector connected to the electrostatic mechanism is moved upon operation of the electrostatic mechanism to change the thickness of the air gap and thereby tune the Fabry-Perot cavity.