Abstract: The present invention provides an electro-optical distance measurement, wherein a light from a light source (6) is projected toward an object to be measured (2), a reflection light reflected by the object to be measured is received at a photodetection unit (8), the light from the light source is received by the photodetection unit as an inner light via an inner optical path (11), and a distance to the object to be measured is measured according to the result of photodetection of the reflection light and the inner light of the photodetection unit, and wherein a correction information is acquired based on the inner light, the acquired correction information is stored, a correction value is obtained from the correction information based on the reflection light and the inner light, and a distance is calculated from the correction value and the result of photodetection of the reflection light and the inner light.

Abstract: An optical instrument includes a controller and a field head arranged for measuring the refractive index of a medium, or a derivable quantity therefrom. The field head includes a measurement prism having a medium-boundary surface, a first wave guide for providing broad-band light from a broad band light source, a dispersive element for dispersing the broad-band light into at least one component light beam of plural component light beams, so that each incident component light beam has a differently directed propagation path and at least one different wave length, and a condenser for collecting at least one component light beam reflected at the medium-boundary surface into a second wave guide. The dispersive element is arranged to direct at least one component light beam into a critical angle of total reflection from the boundary surface, and at least other light beam component into an angle leading into the condenser arranged to collect at least one other component light beam to be passed to a spectrometer.

Abstract: A method of controlling a light beam in an optical system includes a light source that directs a collimated light beam along a path, through a sample, and toward the active area of a stationary detector. The method includes the step selectively moving a lens into the path of the light beam for spreading the beam in instances where the path of the beam is altered by the sample between the source and the stationary detector. The detector, therefore, is held stationary. Adjustment means are provided for increasing the intensity characteristic of the light that reaches the detector to account for a decrease in intensity that occurs when the lens is in the path of the light beam to spread the beam.

Abstract: A critical-angle refractometer which utilizes an in image of light reflected from an optical interface with a vessel containing a sample under test to determine an optical property of the sample, sample properties are evaluated to prevent improper testing of the sample. This evaluation includes establishing reflectance information associating the amount of reflection with locations in the image; and utilizing a plurality of properties of the reflectance information to determine if the vessel contains a proper sample under test.

Abstract: The invention relates to a device for monitoring a urea solution in a tank of a motor vehicle tank. This device comprises a light source capable of emitting a light beam, a photodetector capable of detecting a portion of a light beam emitted by the light source and a part made of a material allowing the propagation of a light beam emitted by the light source. The part has moreover a surface intended to be in contact with the urea solution. The light source, the photodetector and the part are arranged in such a way that a light beam emitted by the light source is propagated by the surface of the part, by reflection or by refraction, toward the photodetector.

Abstract: A method and apparatus provide identification of a spherical error of a microscope imaging beam path in a context of microscopic imaging of a sample using a microscope having an objective. A coverslip that carries or covers the sample is arranged in the imaging beam path. A measurement beam is guided through the objective onto the sample in a decentered fashion that is outside an optical axis of the objective. The measurement beam is reflected at an interface of the coverslip with the sample and the reflected measurement beam is guided through the objective onto a detector. An intensity profile of the reflected measurement beam is detected with the detector and a presence of a spherical error from the intensity profile is determined qualitatively and/or quantitatively.

Abstract: A device for measuring refractive index of medium based on optical delay technology comprises: a signal processing and controlling module, an optical transmitter module, and an optical receiver module, wherein the signal processing and controlling module controls the optical transmitter module to transmit an optical signal having a certain wavelength; the optical signal is injected into a medium to be measured; the optical signal is transmitted and delayed by the medium; the optical receiver module receives the optical signal delayed, and transforms the optical signal delayed into a electrical signal; the electrical signal is amplified and transmitted to the signal processing and controlling module; the signal processing and controlling module measures a delay time between transmitting and receiving the optical signal; and the refractive index of the medium at the certain wavelength is calculated based on the delay time and a known length of the medium.

Abstract: A method is provided for remotely measuring index of refraction fluctuations. From a first location, an optical beam is focused at a focal plane located at a second location in a medium of interest. As a result, a beam of energy is backscattered towards the first location. At the first location, a size of the backscattered beam is determined where the size is indicative of strength of fluctuations in the medium's index of refraction.

Abstract: The present invention relates to systems and methods for minimizing or eliminating diffusion effects. Diffused regions of a segmented flow of multiple, miscible fluid species may be vented off to a waste channel, and non-diffused regions of fluid may be preferentially pulled off the channel that contains the segmented flow. Multiple fluid samples that are not contaminated via diffusion may be collected for analysis and measurement in a single channel. The systems and methods for minimizing or eliminating diffusion effects may be used to minimize or eliminate diffusion effects in a microfluidic system for monitoring the amplification of DNA molecules and the dissociation behavior of the DNA molecules.

Abstract: Optical sensor for detecting an analyte (4), the sensor comprising a photonic crystal, the photonic crystal comprising an analyte—sensitive polymeric material (1) which material is deformable by contact with said analyte (1), by which contact an optical property of the photonic crystal is altered or of which material (1) a refractive index is changed by contact with said analyte (4) and which analyte—sensitive material (1) forms part of a periodic structure (3,4) of the photonic crystal, the structure (3,4) having alternating zones of a relatively high refractive index and zones of a relatively low refractive index, which alternating zone are provided in one or two orthogonal directions of the analyte—sensitive material (1).

Abstract: A method and device for periodically perturbing the flow field within a microfluidic device to provide regular droplet formation at high speed.

Abstract: Methodology of determining refractive index and extinction coefficient of a prism shaped material, including simultaneously for a multiplicity of wavelengths using an easy to practice technique.

Abstract: The present invention relates to a microrefractometer using defocusing imaging. The refractometer includes: a target in which a target micrometer and a reference fluid, an index of refraction of which is known, are positioned; an objective lens receiving light that has been emitted from a light source and passed through the target; an aperture including a plurality of pin holes which divide an optical path of the light having passed through the objective lens; and a camera photographing defocused images formed on an image plane of the refractometer by the light having passed through the aperture.

Abstract: An instrument for optically measuring at least one property of a test medium, includes a light source for emission of light, a light management unit for guiding the light onto and/or into and through a detection space in the test medium, a light detection unit for detecting a fraction of the light scattered, reflected or transmitted by the test medium, a power management unit, and a data management unit. The instrument further includes or is coupled to a power source via a source wiring. The power management unit distributes energy from the power source via a buffer wiring to the light source, and via a further wiring to the light detection unit and the data management unit. The data management unit exchanges measurement data via signal wiring with the light detection unit with a receiving unit. The instrument is adapted to be operated in a potentially hazardous environment.

Abstract: The invention relates to a method for in-line measuring the active KOH concentration in a KOH etching process in which process silicon hydroxide is produced by a reduction reaction according to the formula: 2K+ (aq.)+2OH? (aq.)+2H2O+Si?2K+ (aq.)+H2SiO42? (aq.)+2H2 (g). The total concentration of KOH bath is measured by using a refractometer and the measurement result is corrected by the estimated K2H2SiO4 concentration.

Abstract: A method is presented for use in fabrication of metal islands on an oxide substrate. The method comprises: depositing a selected metal on the oxide substrate by evaporation of said selected metal; and annealing a film of the selected metal on said substrate at temperatures including an annealing temperature being less than 50° c lower than a glass transition temperature, thereby forming the metal islands partially embedded in said substrate.

Abstract: A method of measuring a refractive index distribution includes steps of setting a plurality of different arrangements by a translation movement in a state where an object is arranged in first and second media having refractive indices different from a refractive index of the object, measuring transmissive wavefront of the object for each of media and each of the plurality of arrangements by reference light entering the object (S400), obtaining wavefront aberration corresponding to a difference between each transmissive wavefront and a reference transmissive wavefront (S500), obtaining refractive index distribution of the object by removing an influence of a shape error of the object using wavefront aberration of two media in which the object is arranged at the same position (S70), and obtaining refractive index distribution information of the object based on a plurality of refractive index distributions corresponding to the plurality of arrangements (S80).

Abstract: A critical-angle refractometer which utilizes an in image of light reflected from an optical interface with a vessel containing a sample under test to determine an optical property of the sample, sample properties are evaluated to prevent improper testing of the sample. This evaluation includes establishing reflectance information associating the amount of reflection with locations in the image; and utilizing a plurality of properties of the reflectance information to determine if the vessel contains a proper sample under test.

Abstract: By using two probe optical systems for measurement by disposing the probe optical systems with a test object sandwiched therebetween, an optical path length of light transmitted through the test object which is identified locally is calculated using an interference signal thereof. In addition, a geometrical thickness of the same part is calculated by measuring positions of the probe optical systems, whereby two calculated values are obtained. Based on the values and a calculated value for a reference object, a refractive index distribution of the test object is obtained.

Abstract: A critical-angle refractometer which utilizes an in image of light reflected from an optical interface with a vessel containing a sample under test to determine an optical property of the sample, sample properties are evaluated to prevent improper testing of the sample. This evaluation includes establishing reflectance information associating the amount of reflection with locations in the image; and utilizing a plurality of properties of the reflectance information to determine if the vessel contains a proper sample under test.

Abstract: A refractive index sensor having one or more sources, an adaptive optical element or scanner, imaging optics, a sensing optic, and one or more detectors. The scanner impinges a signal from the source into the sensing optic and onto a sensor-sample interface at sequential angles of incidence. The detector response increases dramatically to signals reflected from the interface at corresponding sequential angles of reflection equal to or greater than a critical angle. The refractive index sensor also uses an input lens between the scanner and the sensing optic and uses an output lens between the sensing optic and the detector. A processor controls the sensor and can determine index of refraction of the fluid sample based on the detector response and scan rate. The sensor can be used in several operational environments from a laboratory to a downhole tool, such as a formation tester to determine properties in a borehole environment.

Abstract: A method includes the steps of measuring a first transmitted wavefront in a first medium having a first refractive index and a second transmitted wavefront in a second medium having a second refractive index different from the first refractive index, and obtaining a refractive index distribution projected value of the object in each orientation by removing a shape component of the object utilizing measurement results of the first transmitted wavefront and the second transmitted wavefront and each transmitted wavefront of a reference object that has the same shape as that of the object and a specific refractive index distribution and is located in one of the first medium and the second medium with the same orientation as that of the object, and calculating a three-dimensional refractive index distribution of the object based on a plurality of refractive index distribution projected values corresponding to the plurality of orientations.

Abstract: A measuring method includes measuring a sum of an optical path length of a test object and a first medium in a first container, introducing light into an area that includes the first medium but does not include the test object and measuring the optical path length of the first medium, measuring a sum of the optical path length of the test object and a second medium in a second container, the second medium having a refractive index different from that of the first medium, introducing the light into an area that includes the second medium but does not include the test object and of measuring the optical path length of the second medium, and calculating a refractive index of the test object based on the measured optical path lengths and an actual distance of an optical path for which each optical path length is measured.

Abstract: A system for controlling a light beam in an optical setup includes a light source that directs a collimated light beam along a path, through a sample, and toward the active area of a stationary detector. A lens is selectively movable into the path of the light beam for spreading the beam in instances where the path of the beam is altered by the sample between the source and the stationary detector. The detector, therefore, is held stationary. Adjustment mechanisms are provided for increasing the intensity characteristic of the light that reaches the detector to account for a decrease in intensity that occurs when the lens is in the path of the light beam to spread the beam.

Abstract: The present invention relates to a microrefractometer using defocusing imaging. The refractometer includes: a target in which a target micrometer and a reference fluid, an index of refraction of which is known, are positioned; an objective lens receiving light that has been emitted from a light source and passed through the target; an aperture including a plurality of pin holes which divide an optical path of the light having passed through the objective lens; and a camera photographing defocused images formed on an image plane of the refractometer by the light having passed through the aperture.

Abstract: The measuring method includes a step of causing reference light to enter an object placed in a first medium to measure a first transmitted wavefront, a step of causing the reference light to enter the object placed in a second medium to measure a second transmitted wavefront, a step of measuring first and second placement positions where the object is placed in the first and second media, and a calculating step of calculating an internal refractive index distribution of the object by using measurement results of the first and second transmitted wavefronts. The calculating step calculates the internal refractive index distribution from which a shape component of the object is removed by using the measurement results of the first and second transmitted wavefronts, and first and second reference transmitted wavefronts of a reference object to be placed at positions identical to the first and second placement positions.

Abstract: A method of detecting the presence of bacterial spores in a sample comprises non-destructively to the spores carrying out the steps of assessing the absorption, reflectance, and/or index of refraction (IOR) of the sample, subjecting the sample to UV radiation, and reassessing the absorption, reflectance, and/or index of refraction (IOR) of the sample to determine the presence or absence of spores. A detector is also disclosed.

Abstract: The method measures first transmitted wavefronts and second transmitted wavefronts by respectively causing reference light to enter an object placed in plural placement states in a first medium and a second medium, calculates an aberration sensitivity with respect to changes of the placement state of the object, and calculates an alignment error of the object in each placement state by using the aberration sensitivity and the first and second transmitted wavefronts measured in each placement state. The method further calculates first and second reference transmitted wavefronts respectively acquirable when causing the reference light to enter the reference object placed in placement states including the alignment errors in the first medium and the second medium, and calculates a refractive index distribution of the object which a shape component thereof is removed, by using the first and second transmitted wavefronts and the first and second reference transmitted wavefronts.

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: A method includes measuring a transmitted wavefront of a test object by introducing reference light into the test object arranged in a medium having a refractive index different from a refractive index of the test object, and calculating a refractive index distribution of the test object by using a measurement result of the transmitted wavefront. The measuring step measures a first transmitted wavefront for a first wavelength and a second transmitted wavefront for a second wavelength different from the first wavelength. The calculating step calculates the refractive index distribution of the test object by removing a shape component of the test object utilizing measurement results of the first and the second transmitted wavefront, and a transmitted wavefront of a reference object arranged in the medium for each of the first and second wavelengths. The reference object has the same shape as the test object and a specific refractive index distribution.

Abstract: The present invention is directed to temperature modulated refractive index measurement. In accordance with the invention a method for determination of the complex temperature coefficient of the refractive index of a sample is provided, wherein the determination of the complex temperature coefficient of the refractive index of the sample is based on a refractive index measurement. Furthermore, the refractive index of the sample is measured over a period of time, wherein the temperature of the sample is modulated over said period of time and the complex temperature coefficient of the refractive index is calculated on the basis of the refractive index measurement over the period of time and the temperature modulation over the period of time. Additionally, a measurement system, in particular comprising a temperature control system and a processing system to carry out the above method, is disclosed.

Abstract: A refractive index measurement apparatus 1 includes a light source 10, a measurement cell (12, 22) including a sample (125, 226) as an object of refractive index measurement and diffracting light incident from the light source, a detector 13 that detects the amount of diffracted light in at least one diffraction order other than zero order of diffracted light exiting from the measurement cell, and a control unit 15 that determines refractive index of the sample corresponding to measured value of the amount of diffracted light detected in at least one diffraction order by the detector.

Abstract: Described herein are devices and methods for making extremely accurate measurements in a medium by continuously measuring the index of refraction of the medium such as water or biological tissue. Also described herein is a device for constantly measuring the index of refraction, and using the index of refraction data to constantly calibrate the optical measurement device. In addition, a primary measurement device (a ladar) that is optimized for data collection in a volume backscattering medium such as water or biological tissue is described, along with data results from the lab.

Abstract: A method for measuring optical properties of an optically variable marking applied on an object, the method including the steps of illuminating the optically variable marking so as to form a first light reflected by the marking at a first view angle and a second light reflected by the marking at a second view angle, the first and second lights having different spectral compositions as a result of the optically variable marking, refracting the second reflected light through a optical unit so as to redirect the second reflected light toward an optical sensor, capturing the first light and the second refracted light with the optical sensor simultaneously; and determining optical properties of the optical variable marking based on the captured first and second lights.

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: Plasmon-integrated sensing mechanism comprised of three fundamental parts: a grating structure (2) with a specific metalization thickness (1) for the coupling of photons with the surface plasmons; a fluidic channel structure (4) in which liquid solutions with different refractive indexes will be streamed; and a photo-sensitive substrate (3) that can detect the light (8) which encounters changes in its intensity as the result of excitation of surface plasmons. The photo-sensitive substrate (3) may work according to photo-diode principle or it may work according to plasmon-assisted photo-resistor principle by using thin film amorphous carbon which exhibits resistance change sensitive to temperature.

Abstract: Quantifying a refractive index of a test medium by obtaining spectral data representative for an optical signal being modulated with an optical transfer characteristics of a photonic sensor, the modulation being obtained by combining modulation of a first electromagnetic wave component in an optical filter element with a first periodic transfer spectrum having a first free spectral range and modulation of a second electromagnetic wave component in an optical filter element with a second periodic transfer spectrum having a second free spectral range being different from the first free spectral range. A relative is change induced in the second periodic transfer spectrum by bringing the test medium in proximity with the optical filter element with the second periodic transfer spectrum. The refractive index of the test medium is quantified by determining a wavelength offset of an envelope signal in said spectral data.

Abstract: Systems for enhancing the sensitivity of detecting an optical signal using nonlinear optics and method of performing the same. In one embodiment, a single-photon detection system includes an optical amplifier realized in a waveguide, and a photodetector coupled to an output of the optical amplifier. A light detection and ranging system includes the optical amplifier coupled to an optical source and one photodetector. In another embodiment, a photodetection system includes a plurality of optical frequency converters, coupled to an optical source, that sequentially convert a wavelength of photons of the optical source to a final wavelength, and a single-photon photodetector coupled to the optical frequency converters to detect single photons produced by the optical source. In another embodiment, an optical sensor includes an optical pump, and a transducer including an optical ring cavity coupled to the optical pump and configured to utilize optical four-wave mixing to detect an external stimulus.

Abstract: A downhole fluid analysis tool has a housing and a flow passage for downhole fluid. A device disposed in the tool housing relative to the flow passage has a one or more sources, one or more sensing optics, one or more detectors, and control circuitry. The source generates an input signal. The sensing optic has a refractive index (RI) higher than crude oil and other expected constituents. A sensing surface of the optic optically coupled to the source interfaces with a downhole fluid. When the variable RI of the downhole fluid reaches a defined relationship to the optic's RI, the input signal interacting with the sensing surface experiences total internal reflection, and the reflected signal from the sensing surface remains in the sensing optic and reflects to a detector. The control circuitry monitors the detector's response and indicates gas break out if the response is above a threshold.

Abstract: A device includes one or more reflector components. Each reflector component comprises layer pairs of epitaxially grown reflective layers and layers of a non-epitaxial material, such as air. Vias extend through at least some of the layers of the reflector components. The device may include a light emitting layer.

Abstract: An apparatus arranged to analyze a multi-layer optical material structure, the apparatus constituted of: a control unit, a light source outputting light; and a light receiver arranged to receive the light from the light source after interaction with the target structure, the control unit arranged to: detect the amplitude of the received light as a function of wavelength; perform a transform of a function of the detected amplitudes to the optical thickness domain; determine, responsive to a planned composition of the target multi-layer structure, optical thickness and amplitude of expected peaks of the performed transform to the optical thickness domain which correspond with interactions with single interface between layers; identify actual peaks of the performed transform to the optical thickness domain which correspond with interfaces between layers; and determine at least one physical characteristic of the target structure responsive to the determined peaks.

Abstract: A system for detecting the presence of an analyte in a moving substrate or sample handling device is disclosed, providing means (26,30) for integrated triggering of data acquisition with a detector means (28) and data acquisition with a detector means (28). In particular, a surface Plasmon resonance “lab on disk” reader system is disclosed.

Abstract: An immersion refractometer includes a microchamber having an inlet and an outlet for allowing a sample containing microorganism particles to flow therethrough, wherein the microchamber comprises at least one trapping site for trapping a microorganism particle in each respective trapping site, and a micromixer for mixing a plurality of liquids to form an external medium, wherein the micromixer and the microchamber are in fluid communication to introduce the external medium into the microchamber. Use of the present immersion refractometer in a method of identifying microorganism particles contained in a sample is also provided.

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: The method includes first and second steps of placing an object in first and second media whose refractive indices are lower than that of the object, and of causing the reference light to enter the object to measure first and second transmitted wavefronts. When light rays entering a peripheral portion of the object and passing through a same point of the object are defined as first and second light rays, the method causes these light rays to proceed in directions mutually different to change an NA of the reference light such that the reference light after being transmitted through the object is brought closer to collimated light than that before entering the object. The method calculates an effective thickness of the object using geometric thicknesses thereof and calculates a refractive index distribution thereof using the first and second transmitted wavefronts and the effective thickness.

Abstract: Method and apparatus for detecting a species in a dilute medium, the species having a spectral feature, the apparatus comprising: a beam source arranged to generate a first laser beam and a second laser beam coherent with each other, and having a matching chirp pattern. Beam guide arranged to pass at least the first laser beam through the dilute medium; a beam mixer arranged to mix the first and the second laser beams to form a mixed beam. Detector arranged to detect, during the chirp pattern, the mixed beam and to measure changes in the mixed beam caused by refractive index variations in the dilute medium across a spectral feature. Output providing a signal that changes in response to the measured changes.

Abstract: A refractometer has a housing (1), a measurement cell (8) arranged in the housing (1), and a lid unit (2). The lid unit has a base plate (3) with a cutout (7) allowing access to the measurement cell, and a lid (4) for covering the measurement cell. The lid is connected to the base plate by way of a hinge. The lid unit also has a lid insert (11, 17, 18, 28, 31, 35, 39) that is arranged replaceably in the lid. The lid unit (2) is detachably connected to the housing by means of a connecting element that is itself connected to the base plate.

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 method includes measuring a transmitted wavefront of a test object by introducing reference light into the test object arranged in a medium having a refractive index different from a refractive index of the test object, and calculating a refractive index distribution of the test object by using a measurement result of the transmitted wavefront. The measuring step measures a first transmitted wavefront for a first wavelength and a second transmitted wavefront for a second wavelength different from the first wavelength. The calculating step calculates the refractive index distribution of the test object by removing a shape component of the test object utilizing measurement results of the first and the second transmitted wavefront, and a transmitted wavefront of a reference object arranged in the medium for each of the first and second wavelengths. The reference object has the same shape as the test object and a specific refractive index distribution.

Abstract: A critical-angle refractometer which utilizes an in image of light reflected from an optical interface with a vessel containing a sample under test to determine an optical property of the sample, sample properties are evaluated to prevent improper testing of the sample. This evaluation includes establishing reflectance information associating the amount of reflection with locations in the image; and utilizing a plurality of properties of the reflectance information to determine if the vessel contains a proper sample under test.