Abstract: A beam deflection technique for simultaneous measurements of the thickness, refractive index and optical absorption of transparent materials using a charge coupled device (CCD) camera is provided. The method comprises measuring beam deflection after transmission through or reflection off a sample of interest at variable incidence angles to the sample surface. The measurement of beam deflection as a function of incident angle is related through Snell's Law directly to the sample thickness and sample index of refraction.

Abstract: A fluid detector system for identifying a fluid or detecting presence of a substance in a fluid. The fluid detector includes at least two optical conductors, optical detectors coupled to outputs from the optical conductors; and a comparer for comparing the outputs from the detectors. Each optical conductor has an outer reflective surface. A first one of the optical conductors has a section with at least a portion of its outer reflective surface removed. The comparer can determine an optical refraction index of fluid at the section of the first optical conductor which has the portion of the outer reflective surface removed.

Abstract: An apparatus for performing optical measurements comprising a first prism having a first sample surface, the first sample surface operatively arranged to receive a first sample, the first sample surface operatively arranged to reflect incident light, a first detector operatively arranged to measure intensity of light reflected from the first sample surface of said first prism, a second prism having a second sample surface, the second sample surface operatively arranged to receive a second sample, the second sample surface operatively arranged to reflect incident light, a second detector operatively arranged to measure intensity of light reflected from the second sample surface of the second prism, and, means to determine an optical characteristic based on the intensities of light measured by said first and the second detectors. The invention also includes a method for performing optical measurements.

Abstract: The present invention provides a method for inferring optical parameters of a sample in a predictive spectral range by use of the known values of the optical parameters in a predetermined measurement spectral range. The method of the present invention capitalizes on the Forouhi-Bloomer dispersion equations for the optical constants n and k.

Abstract: In a projection optical system for projecting and transferring a pattern on a projection original R onto a photosensitive substrate W, one or a plurality of lenses having an in-homogeous radial refractive index about the optical axis are used, while one or a plurality of aspheric surfaces for correcting the aberration resulting from the in-homogeousness in refractive index of lenses are provided.

Abstract: Disclosed herein is a measuring apparatus utilizing attenuated total reflection. The measuring apparatus is equipped with a dielectric block, a thin film layer formed on one surface of the dielectric block, an optical system for making a light beam enter the dielectric block so that a condition for total internal reflection is satisfied at an interface between the dielectric block and the thin film layer, and a two-piece photodiode for detecting the light beam totally reflected at the interface. When attenuated total reflection is detected a plurality of times for a single sample, the two-piece photodiode is disposed at a predetermined position relative to a dark line when a first measurement is made. The two-piece photodiode is also disposed at the same position as the predetermined position stored in a storage unit when a second measurement and measurements thereafter are made.

Abstract: The invention relates to refractometry and attenuated reflectance spectrometry in a wellbore environment. Specifically, it pertains to a robust apparatus and method for measuring refractive index of fluids along a continuum (rather than in steps), and for measuring attenuated reflectance spectra, and for interpreting the measurements made with this apparatus to determine a variety of formation fluid parameters. The present invention provides a method and apparatus to distinguish between gas and liquid based on the much lower index of refraction of gas. It can also be used to monitor fluid sample clean up over time. The refractive index of a wellbore fluid is determined from the fraction, R, of light reflected off the interface between a transparent window that has a known refractive index and this fluid. Preferably, the refractive index is measured at some wavelength of light for which the fluid is not highly attenuating.

Abstract: Phase manipulation is used to produce a high contrast electron microscope image. A phase plate is placed at the back focal plane of an objective lens and used to form a differential contrast image.

Abstract: An optoelectronic liquid sensor indicates failure of operative components therein. The sensor includes a light source, a light detector, and a transparent probe which functions as a primary liquid sensing prism. The transparent probe is of a suitable configuration permitting internal reflection of light transmitted therethrough from the light source, along a primary light path for reception by the light detector, when the light-impinged surface of the primary prism is in air. When the same surface of the probe is submersed in or exposed to liquid, light from the light source traveling along the primary light path is refractively transmitted into the liquid, and therefore almost no light reaches via the primary light path. A secondary light path is provided, along which a fraction of the light from the light source is also transmitted via internal reflection within a transparent body to the light detector.

Abstract: A system and method of reconstructing an image of a structure having periodic variations in index of refraction. Electromagnetic waves are projected onto the structure and the resulting diffracted electromagnetic waves are measured, wherein the step of measuring includes the step of determining a plurality of intensities DE. Refractive terms can then be calculated as a function of the intensities DE.

Abstract: An optical configuration for measuring a difference in refractive index between a first sample and a second sample comprises partitioned first and second optical interfaces symmetrically illuminated by an illumination beam to provide first and second partial beams defined by the refractive index of the first and second samples, respectively. A linear scanned array is aligned in a meridional plane of the optical configuration for detection purposes, and an optical multiplexor is provided upstream of the linear scanned array for receiving the first and second partial beams and defining first and second optical channels carrying optical signal information corresponding to the first and second partial beams. The optical multiplexor switches between optical channels, such that the linear scanned array detects either the first or second optical channel at a given time. Thus, differential measurements are possible using a single linear array.

Abstract: A sensor array is bonded to or molded together with a micro-lens array to form a sensor cartridge. The micro-lenses of the micro-lens array are configured to focus light incident on the sensors, into the sensors. An alignment structure has a mating profile that receives and engages one or more micro-lenses from the micro-lens array to laterally align the cartridge to enable repeatable precise positioning of the cartridge.

Abstract: The present invention relates to the field of medical technique, and more precisely relates to refractometers used for determining vision parameters. A refractometer of the present invention increases the accuracy of measuring vision parameters while simplifying refractometer design. This device can further be used to train the eye muscles using corresponding medical methodologies. The first embodiment of the refractometer comprises an optical focusing element (1), a test-object (2), an optical axis (3), and a measuring element (4). The optical focusing element is in optical alignment with the test-object, which in the case of a normal vision placed in the focus of the optical focusing element. The optical focusing element and the test-object are arranged so as to allow their mutual displacement along the optical axis.

Abstract: A method for designing and tuning a refractive index of a magnetic fluid is performed by adjusting some characteristic parameters. The characteristic parameters include the type of carrier, the type of magnetic particles, the concentration of the magnetic ingredient; the wavelength of an intended light onto the magnetic fluid layer; the strength of applied magnetic field; the sweep rate of the magnetic field; the direction of the applied magnetic field; the strength of applied magnetic field associated with the thickness of the magnetic fluid layer; and the strength of applied magnetic field associated with the temperature. A magnetic fluid with a designed value of refractive index under zero magnetic field is synthesized by carefully selecting the carrier and the volume concentration of the magnetic particles, and this value can further be tuning around the designed value by changing the forgoing characteristic parameters.

Abstract: The invention relates to refractometry and attenuated reflectance spectrometry in a wellbore environment. Specifically, it pertains to a robust apparatus and method for measuring refractive index of fluids along a continuum (rather than in steps), and for measuring attenuated reflectance spectra, and for interpreting the measurements made with this apparatus to determine a variety of formation fluid parameters. The present invention provides a method and apparatus to distinguish between gas and liquid based on the much lower index of refraction of gas. It can also be used to monitor fluid sample clean up over time. The refractive index of a wellbore fluid is determined from the fraction, R, of light reflected off the interface between a transparent window that has a known refractive index and this fluid. Preferably, the refractive index is measured at some wavelength of light for which the fluid is not highly attenuating.

Abstract: An eye model system for remotely predicting the in-vivo performance of a vision altering optic includes a representative cornea, a dispersion medium, and a retinal surface. The corneal surfaces provide anatomical shape, optical power, and higher order aberration content. The dispersion medium mimics chromatic dispersion in an actual eye. The retinal surface is moveable to provide selected defocus. A humidity and temperature enclosure may be provided. Model eye elements can be tilted or decentered to simulate actual conditions. An associated method for remotely measuring the performance of a vision altering optic to predict its performance in-vivo includes making topography, wavefront, interferometry, PSF, MTF, or other optical and/or physical measurements of the model eye system with and without the optic in combination.

Abstract: In the context of the method according to the present invention, the matter for which the refractive index is to be determined, is made available in the form of a theoretically determinable scattering or diffraction pattern. Two or more orders of diffraction are then defined to form at least one intensity ratio. At least one intensity distribution is formed by irradiating the scattering pattern using one light beam of a defined shape. Subsequently thereto, the intensity ratio is formed based on the orders of diffraction of the intensity distribution. In addition, at least one portion of a characteristic curve is determined, which represents the dependency of the intensity ratio on the refractive index, and, with whose assistance, the corresponding refractive index can be assigned to the intensity ratio formed.

Abstract: A method for measuring the optical parameters of a phase object, comprising recording a moiré pattern viewed through said phase object, said moiré pattern being formed by illuminating by means of a source of diffuse light, first and second gratings positioned in the space between said light source and said phase object, wherein the plane of said first grating is parallel to the plane of said second grating, and calculating the optical parameters of interest from said moiré pattern.

Abstract: A sensor apparatus and associated method for sensing and monitoring specific binding of analyte to an immobilized binding layer are disclosed. The apparatus preferably comprises an automatic critical angle refractometer having a linear scanned array and an optical system for illuminating a portion of the array, which illumination depends upon the refractive index of the binding layer deposited on an optically transparent element. The apparatus further includes a flow cell for bringing the analyte in contact with the binding layer. The apparatus also includes a computer for receiving and processing refractive index data from the critical angle refractometer during the reaction between the analyte and the layer, which computer may be peripherally connected to the refractometer or enclosed within the refractometer housing.

Abstract: In order to measure the refractive index of a medium (18), for example a liquid or a gas, this system comprises a waveguide (14) having a blazed Bragg grating (16), the spectral response of which depends on the refractive index of the medium, a light source (20) in order to make this light interact with the grating, means (22) for the spectral analysis of the light which has interacted with the grating, means (24) for recovering the spectrum provided by the spectral analysis means and means (26) to correlate, from the recovered spectrum, the spectral response of the grating with one value of the refractive index of the medium.

Abstract: The invention relates to a refractometer and to a method of measuring the refractive index of a medium. An incident light ray is directed onto an interface consisting of a medium of known refractive index and of the medium studied, then the intensity of the reflected light ray is measured. The incident and reflected light rays are propagated in an optical fiber section. The ratio between the intensity of the incident ray and the intensity of the reflected ray allows the refractive index of the medium studied to be calculated by means of Fresnel's formulas.

Abstract: The present invention provides a method and system for controlling mineral scale deposition from a formation fluid. The rate at which scaling is occurring is measured in real time using an attenuated total reflectance probe and a photometer. The results are then used to determine whether to increase, decrease or leave unchanged addition of anti-scaling additives.

Abstract: Disclosed are a method and an apparatus for precision optical measurement of solute concentration and temperature of a transparent liquid. The apparatus includes a vessel (12) which contains a sample of liquid (14), the refractive index of which is to be determined, a light source (22) and a beam position sensor (30). The vessel (12) has an entrance side and an exit side, with a known angular relationship therebetween, and is situated in a known ambient The light source (22) is located so as to cause a beam of light to impinge on the entrance side at an angle with respect to a normal to an outer surface of the entrance side, to pass through the liquid (14), and to then pass through the exit side, from which it exits at an angle with respect to a normal to an outer surface of the exit side. The beam position sensor (30) provides data for determining the exit angle thereby permitting the refractive index of the liquid to be determined, based on the angles.

Abstract: Optical sensors and methods are disclosed. The resonance energy transfer between a donor and acceptor pair on a surface is monitored. The change in resonance energy transfer as a function of the change in refractive index of a sensing area disposed between the donor and acceptor pair is utilized to provide various sensing methods and structures.

Abstract: Optical sensors and methods are disclosed. The resonance energy transfer between a donor and acceptor pair on a surface is monitored. The change in resonance energy transfer as a function of the change in refractive index of a sensing area disposed between the donor and acceptor pair is utilized to provide various sensing methods and structures.

Abstract: Apparatus and method for determining at least one parameter, e.g., concentration, of at least one analyte, e.g., urea, of a biological sample, e.g., urine. A biological sample particularly suitable for the apparatus and method of this invention is urine. In general, spectroscopic measurements can be used to quantify the concentrations of one or more analytes in a biological sample. In order to obtain concentration values of certain analytes, such as hemoglobin and bilirubin, visible light absorption spectroscopy can be used. In order to obtain concentration values of other analytes, such as urea, creatinine, glucose, ketones, and protein, infrared light absorption spectroscopy can be used. The apparatus and method of this invention utilize one or more mathematical techniques to improve the accuracy of measurement of parameters of analytes in a biological sample.

Abstract: A method and apparatus for fluid analysis includes a sensor for determining the index of refraction of a fluid. Advanced methods of fluid analysis relate index of refraction and other measured physical characteristics of the fluid.

Abstract: A method and system for determining a spatially local index of refraction in optical materials is provided. Light, including a near-field intensity, is collected above a surface of the material. A probe is oscillated at a plurality of frequencies and in a substantially perpendicular manner relative to the surface of the material to detect the near-field intensity of the light. A distance of the probe from the surface of the material is modulated. Based on a ratio of the near-field intensity of the light detected at the plurality of frequencies, the local index of refraction is determined.

Abstract: An optoelectronic liquid sensor indicates failure of operative components therein. The sensor includes a light source, a light detector, and a transparent probe which functions as a primary liquid sensing prism. The transparent probe is of a suitable configuration permitting internal reflection of light transmitted therethrough from the light source, along a primary light path for reception by the light detector, when the light-impinged surface of the primary prism is in air. When the same surface of the probe is submersed in or exposed to liquid, light from the light source traveling along the primary light path is refractively transmitted into the liquid, and therefore almost no light reaches via the primary light path. A secondary light path is provided, along which a fraction of the light from the light source is also transmitted via internal reflection within a transparent body to the light detector.

Abstract: A beam deflection technique for simultaneous measurements of the thickness, refractive index and optical absorption of transparent materials using a charge coupled device (CCD) camera is provided. The method comprises measuring beam deflection after transmission through or reflection off a sample of interest at variable incidence angles to the sample surface. The measurement of beam deflection as a function of incident angle is related through Snell's Law directly to the sample thickness and sample index of refraction.

Abstract: The use of an intensity spectrum as a fingerprint to determine the layer structure of a semiconductor wafer product or partial product, thereby to determine the routing history of the product through a production line and prevent routing errors. Also, a production line having a plurality of successive stages for construction of a product such as a semiconductor wafer, and routers for transferring partly constructed product between the stages such that each stage receives a respective predefined partly constructed product as its input.

Abstract: A hand-held automatic refractometer comprises a completely fluid-sealed housing enclosing a wireless transmitter for transmitting digital measurement data to a remote computer having a corresponding receiver connected thereto. The refractometer housing protects the internal components, including the transmitter, from damage caused by test fluids and cleaning fluids.

Abstract: The invention relates to a method and system for measuring the internal refractive index of an optical fiber preform with high precision. The internal refractive index of an optical fiber preform (2) is measured from the state of bending of a light ray (4) passing across the optical fiber preform (2), so that the refractive index distribution of the optical fiber preform (2) is found on the basis of the angle of bending of the light ray calculated from a specific relation between a light ray start position (8) and a light ray detection position (9). The surface of a light source (1) is scanned by a knife-edge (6) and the light ray start position (8) on the light source is determined depending on the interception of the light ray (4) by the knife-edge (6) or the de-interception of the light ray, thereby learning the start position (8) of the detected light ray (4) on the light source (1).

Abstract: A device for controlling the quality of microdroplets deposited on a substrate comprises a light source for illuminating the substrate which has the microdroplets deposited thereon. An image generator is provided for receiving the light which has been produced by the light source, fallen through the substrate or reflected by the substrate, so as to generate an image. Furthermore, an identifier and an analyzer are provided for analyzing the generated image with respect to patterns created in said image as a result of a refractive effect produced by microdroplets deposited on the substrate.

Abstract: A hand-held automatic refractometer comprises a completely fluid-sealed housing enclosing a wireless transmitter for transmitting digital measurement data to a remote computer having a corresponding receiver connected thereto. The refractometer housing protects the internal components, including the transmitter, from damage caused by test fluids and cleaning fluids.

Abstract: A system for reprocessing and sterilizing a previously used endoscope having at least one lumen is disclosed. The reprocessing system includes a reaction chamber into which individual chemical components of a sterilant are transferred by pneumatic force. The system includes a central processor which controls the asynchronous reprocessing and sterilization of at least two endoscopes. A novel sterilant is also disclosed. Also disclosed is a combination of the sterilization device and the sterilant and methods of using the same.

Abstract: A sensor apparatus and associated method for sensing and monitoring specific binding of analyte to an immobilized binding layer are disclosed. The apparatus preferably comprises an automatic critical angle refractometer having a linear scanned array and an optical system for illuminating a portion of the array, which illumination depends upon the refractive index of the binding layer deposited on an optically transparent element. The apparatus further includes a flow cell for bringing the analyte in contact with the binding layer. The apparatus also includes a computer for receiving and processing refractive index data from the critical angle refractometer during the reaction between the analyte and the layer, which computer may be peripherally connected to the refractometer or enclosed within the refractometer housing.

Abstract: The surface contribution to appearance of an object is characterized using a plurality of viewing and illumination angles. The color determining and surface contribution are determined to aid in the predicting of the appearance of an object as well as matching an object to another object.

Abstract: The present invention provides a method for inferring optical parameters of a sample in a predictive spectral range by use of the known values of the optical parameters in a predetermined measurement spectral range. The method of the present invention capitalizes on the Forouhi-Bloomer dispersion equations for the optical constants n and k.

Abstract: A surface plasmon sensor which can be placed under a liquid sample or in a humid atmosphere during operation. The surface plasmon sensor is constituted of a dielectric block 11, a metal film 12 which is superposed on one surface of the dielectric block 11, a light source 14 for generating a light beam 13, a front optical system 15 which enables the light beam 13 to realize a variety of angles of incidence on an interface 11a between the dielectric block 11 and the metal film 12, each of the angles satisfying a condition for total reflection on the interface 11a, including those angles satisfying a condition for the surface plasmon resonance, and a photodetector 16 which detects a state of the surface plasmon resonance by measuring intensity of the light beam 13 after the light beam 13 is totally reflected at the interface 11a.

Abstract: A device and a method enable the rapid, quantitative evaluation of a large collection of ligands for binding affinity with a certain immobilized receptor, the improvements being that binding pan be detected without the need for a label and that binding is carried out in solution phase at a high rate. The instrument has at least two embodiments, one is based on a sensitive absorption photometer and the other on a sensitive light scatter photometer operating at a specific resonance wavelength, &lgr;R, of small, metallic, colloidal particles. The resonance is present in small particles having a complex refractive index with real part n(&lgr;) approaching 0 and imaginary part k(&lgr;) approaching 2 simultaneously at a specific wavelength &lgr;R. The particles are substantially spherical and substantially smaller than &lgr;R. The receptor is immobilized on a suspension of such particles and ligand binding is detected by a change in optical absorption or light scatter at the resonance wavelength.

Abstract: A detection system for use in detecting the presence of a non-aqueous organic measurand is provided. The system comprises a fibre-optic probe assembly incorporating an optical fibre which is susceptible to micro bending anywhere along its length, and a body of material contained within a rigid containment structure, wherein said body comprises a material selected from the group consisting of a rubber, plastic and semi-crystalline/rubbery polymeric material which is subject to a volumetric change capable of inducing a microbend in said optical fibre in the presence of said non-aqueous organic measurand and wherein the body of material is a substantially continuous coating which has a thickness prior to contact with the non-aqueous measurand of less than 7.

Abstract: Disclosed is a system for the characterization of thin films and interfaces between thin films through measurements of their mechanical and thermal properties. In the system light is absorbed in a thin film or in a structure made up of several thin films, and the change in optical transmission or reflection is measured and analyzed. The change in reflection or transmission is used to give information about the ultrasonic waves that are produced in the structure. The information that is obtained from the use of the measurement methods and apparatus of this invention can include: (a) a determination of the thickness of thin films with a speed and accuracy that is improved compared to earlier methods; (b) a determination of the thermal, elastic, and optical properties of thin films; (c) a determination of the stress in thin films; and (d) a characterization of the properties of interfaces, including the presence of roughness and defects.

Abstract: A method for determining a cell crossing number of a shadowline between illuminated and dark regions of a linear scanned array of photosensitive cells, and an automatic refractometer using the method, are disclosed. The array is scanned to extract a response signal from each of the photosensitive cells, and the response signals are converted from are converted from analog form to digital pixels, thus yielding a set of data points that collectively represent an illumination distribution curve over the array. A range of cells within which the shadowline resides is established by analyzing the illumination curve data. The second derivative of the illumination distribution curve over the established range of cells is calculated and the greatest positive area bounded by the second derivative is identified. The centroid of the greatest positive area is found and its cell number coordinate is deemed the cell crossing number of the shadowline.

Abstract: An apparatus and method for on-column analysis in flash chromatography. The detection scheme utilizes refractive index changes as analytes move through an illuminated region of a chromatography column. The column packing material is a diffuse scattering medium when the refractive index of the solvent is significantly different than that of the packing material. The magnitude of the signal depends on the degree to which the refractive index mismatch is changed as an analyte passes through the illuminated region. This detection scheme provides a simple, inexpensive means for monitoring the end of a flash chromatography column to determine the exit time of the species of interest, thus greatly reducing the post-column analysis time. Additionally, the detector is movable along the length of the column, offering the potential to monitor separations as they occur.

Abstract: A sensor for measuring the change in refractive index of a liquid uses the lowest critical angle of a normal fiber optic to achieve sensitivity when the index of the liquid is significantly less than the index of the fiber core. Another embodiment uses a liquid filled core to ensure that its index is approximately the same as the liquid being measured.

Abstract: The invention relates to a refractometer comprising an optical module (4) arranged floatingly inside a housing structure, which module comprises an optical window (2) to be positioned in a process fluid (3), and means for forming an illuminating beam and for directing it into the process fluid (3) through the optical window (2) and for directing back the part of the illuminating beam that is reflected from the process fluid, and further, means for watching the image formed in said manner. The optical module (4) is arranged to be supported against the housing structure by means of sealing (5) arranged between the optical window (2) and the housing structure. In order to provide a device suitable for difficult conditions, the housing structure part (6) in contact with the process fluid (3) against which the optical window (2) is arranged to be supported via sealing (5) is formed of a material that is chemically durable, mechanically rigid and durable and has good thermal conductivity.

Abstract: This document describes an optical sensor unit and a procedure for the specific detection and identification of biomolecules at high sensitivity in real fluids and tissue homogenates. High detection limits are reached by the combination of i) label-free integrated optical detection of molecular interactions, ii) the use of specific bioconstituents for sensitive detection and iii) planar optical transducer surfaces appropriately engineered for suppression of non-specific binding, internal referencing and calibration. Applications include the detection of prion proteins and identification of those biomolecules which non-covalently interact with surface immobilized prion proteins and are intrinsically involved in the cause of prion related disease.

Abstract: The present invention relates to a method for the determination of refractive indices, ranging over a wide range of values. It also relates to a method for the determination of the birefringence of liquid crystals. Further, it relates to optical instruments used for such determinations.

Abstract: An apparatus for measuring an optical characteristic of an ablation standard object having a known ablation rate, as compared with an object to be processed having a unknown ablation rate which is ablated with laser beam, the apparatus comprising a retaining device for retaining the ablation standard object so that a surface thereof may be at the predetermined height, a refractive power measuring device for measuring a refractive power of the ablation standard object, which includes a projecting optical system for projecting target luminous flux for use in refractive power measurement onto the ablation standard object retained by the retaining device and a detecting optical system for detecting the target luminous flux projected by the projecting optical system, a moving device for moving the refractive power measuring device to the predetermined measuring position in order to measure the refractive power of the ablation standard object, and an output device for outputting results measured by the refractive p