Abstract: The present invention concerns an interferometer comprising: an optical body adapted in operation to mount a measurement area comprising a film which is capable of acting as a two dimensional environment for surface plasmons and an adjacent reference area; an optical beam generation means for irradiating the reference and measurement areas with radiation capable of generating surface plasmon resonance; optical means for combining radiation reflected from the reference and measurement areas, and pixelated detection means for generating data representing two dimensional images of the combined radiation beams.

Abstract: This specification discloses a measuring apparatus for measuring the wavefront aberration of an optical system for a soft X-ray which can highly accurately measure the wavefront aberration of the optical system without using the soft X-ray. This measuring apparatus has a light source for supplying light of a predetermined wavelength, and a detector disposed at a location whereat an interference fringe is formed by the light of the predetermined wavelength passed through the optical system, and measures the wavefront aberration of the optical system on the basis of the result of the detection by this detector. The predetermined wavelength is a wavelength within a wavelength range of 150 nm to 300 nm.

Abstract: A multi-channel imaging system is calibrated by measuring the geometric distortion in each sub-image, generating corresponding correction factors, and applying such factors to correct subsequent image data. In addition, intensity transfer-function arrays are measured at each pixel, and further used to correct for system and detector nonlinearities and nonuniformity between images. The procedure is repeated over a range of wavelengths to produce a complete set of correction coefficients and transfer functions. When the system is used for interferometric phase measurements, multiple measurements are preferably taken and a random phase offset in the reference path length is introduced at each measurement. The multiple phase data so derived are then averaged to reduce phase-dependent systematic measurement errors.

Abstract: Compound surfaces of a test object are interferometrically measured by a multi-beam probe. One of two measuring beams emerges from the probe at a fixed angle for measuring one of the compound surfaces, and the other measuring beam emerges from the probe at a variable angle for measuring a plurality of other compound surfaces.

Abstract: A measuring system for an apparatus having a bed, a first stage movable in a first direction relative to the bed, and a second stage movable in a second direction at right angles to the first direction, relative to the first stage. A first interferometer measures displacement in the first direction between a first reference reflector and a first target reflector fixed to the first stage. A second interferometer (a) measures displacement in the second direction between a second reference reflector and a second target reflector fixed to the second stage, (b) includes an intermediate reflector fixed to the first stage, (c) produces a beam that extends in the first direction from a position fixed to the bed to the intermediate reflector and in the second direction from the intermediate reflector to the second target reflector and (d) can therefore have a head that is mounted on the bed.

Abstract: Fiber optic particle detector for measurements in a fluid flow, comprising an optical fiber (2,3,12) being acoustically coupled to a mechanical element (11,13,14) adapted to be acoustically coupled to the flow, a fiber optic interferometer (54,56) and a light source (12,51,55) providing light in said optical fiber.

Abstract: An apparatus for measuring fruit properties, in order to classify fruit according to internal qualities, measures the sweetness of a fruit sample using near-infrared spectroscopy. The apparatus includes a pair of waveguides (12), a pair of optic emitter/sensor assemblies (14), a light-interrupting unit (20), and a light detector (40). The light detector calculates the intensity of light, transmitted from a light source and received by the optical emitter/sensor assemblies, thus allowing spectral analysis and interpretation for the determination of sweetness and acidity of a variety of fruits. The light detector controls the light-interrupting unit to interrupt the optical path when the light intensity is reduced. The apparatus is suitable for use in an automated line, for effective and reliable measurement of internal fruit properties, to improve operational efficiency and precision in fruit selection.

Abstract: The optical sampling system performs by detecting the interference effect which is a linear correlation between the signal lights and the optical pulses, so that both the signal lights and the optical pulses can have relatively low intensities, and the reception sensitivity is high. Also, the pulse width of the optical pulses and the amount of delay given to the optical pulses are the only factors that limit the time resolution, so that it is possible to provide the optical sampling system with excellent time resolution and power consumption properties, and it is possible for the optical sampling system to monitor not only the intensity of the signal lights but also the frequency modulation component as well.

Abstract: Provided is a grating interference type optical encoder including a scale board, a diffraction grating located on the scale board, a light receiving element, an illumination optical system for emitting a coherent light fluxes to the diffraction grating on the scale board that relatively moves, to produce two diffraction light fluxes having different orders, an arc-shaped grating for re-emitting to the diffraction grating the two diffraction light fluxes having the different orders which are produced in the diffraction grating portion through a deflection unit, and a light guiding unit for superimposing rediffraction light fluxes produced by rediffracting the diffraction light fluxes re-emitted to the diffraction grating and guiding the superimposed rediffraction light fluxes to the light receiving element.

Abstract: Integrated spectroscopy systems are disclosed. In some examples, integrated tunable detectors, using one or multiple Fabry-Perot tunable filters, are provided. Other examples use integrated tunable sources. The tunable source combines one or multiple diodes, such as superluminescent light emitting diodes (SLED), and a Fabry Perot tunable filter or etalon. The advantages associated with the use of the tunable etalon are that it can be small, relatively low power consumption device. For example, newer microelectrical mechanical system (MEMS) implementations of these devices make them the size of a chip. This increases their robustness and also their performance. In some examples, an isolator, amplifier, and/or reference system is further provided integrated.

Abstract: A method and apparatus for measuring the optical thickness and absolute physical thickness of an optically transparent object utilizes a reflective interferometric process. A broadband optical signal is directed toward the object to be measured, and a pair of signals reflected off of the object are processed to determine the optical thickness of the object. When used with an optical fiber preform, the technique can be used to measure the outer diameter of the preform and control the drawing process. If the index of refraction of optically transparent object is known, the absolute physical thickness can also be determined.

Abstract: A interferometer that has no moving parts and can acquire an interferogram in a single exposure is disclosed. Embodiments according to the invention can be used for polychromatic and/or monochromatic detection and include a fixed-position element that divides a beam segment into a plurality of parallel sub-beams of successively increasing path lengths. Embodiments according to the invention can be constructed from separate elements or can be combined into a one-piece device to provide increased stability and ruggedness.

Abstract: An interleaver device and associated methods of manufacturing and calibration that use a laser bending technique to adjust the relative position of interferometers of the interleaver. The interleaver device includes a laterally divided housing with two lateral portions separated by supports. The supports are web like structures, the length of which can be adjusted in a predictable or measurable manner in response to a laser beam. The laser bending calibration and manufacturing technique uses a laser and a feedback and control system to adjust the spacing and angular relation between the lateral portions by partially melting one or more of the supports. The feedback and control system includes an optical detector, a computer, and a positioning system. This combination of components allows the interleaver device to be calibrated to precisely adjust the separation between channels within a WDM optical signal.

Abstract: The invention is directed to the provision of a device and method for measurement of angle of rotation for measuring in a non-contacting fashion the concentration of an optically active substance such as a sugar, amino acid, vitamin, or the like dissolved in a sample. According to the invention, A coherent beam is split into two beams, one being an object beam and the other being a reference beam, the object beam passed through the sample is converted by a quarter wave plate into mutually perpendicular polarization components having therebetween a phase difference proportional to the angle of rotation produced by the sample, and the angle of rotation produced by the sample is obtained from the phase difference occurring between beat signals produced by causing the object beam with the reference beam.

Abstract: Time-correlation methods for determining pulse characteristics from a modelocked ultrafast laser include a cross-correlation method and an auto-correlation method. In the cross-correlation method, pulses from the laser and pulses from another modelocked laser are incident on a two-photon detector that responds when the pulses overlap in time. The lasers are synchronized to the same frequency and the phase difference between pulses from the two lasers is varied to vary the temporal pulse overlap while recording the detector response. Pulse characteristics are determined from recorded data representing the detector response as a function of phase difference. In the auto-correlation method, pulses from one laser are divided into two components. One component follows a fixed delay path before being temporally overlapped at the detector with another component that has not been delayed. The temporal overlap is varied by varying the pulse repetition frequency.

Abstract: A displacement pickup is provided which includes a displaceable scale (12) having defined therein a first area (12a) where positional information is recorded with a predetermined pitch and a second area (12b) where positional information is recorded with a predetermined pitch different from that in the first area (12a), a first reading system (10) to read the positional information recorded in the first area (12a), a first phase detector (14) to detect a first phase on the basis of the positional information read by the first reading system (10), a second reading system (11) to read the positional information recorded in the second area (12b), a second phase detector (15) to detect a second phase on the basis of the positional information read by the second reading system (11), a phase comparator (16) to make a comparison between the first and second phases, and an origin signal generator (17) to generate an origin signal according to the result of comparison from the phase comparator (16).

Abstract: A wavefront measurement system has a source of electromagnetic radiation. An imaging system focuses the electromagnetic radiation at an object plane. A first grating is positioned in the object plane and has a plurality of rulings with randomized height. A stage moves the first grating parallel to the rulings. A projection optical system projects an image of the first grating onto an image plane. A second grating is at the image plane. A detector behind the second grating receives a fringe pattern produced by the second grating.

Abstract: A biosensor embodying the invention includes a sensing volume having an array of pores sized for immobilizing a first biological entity tending to bind to a second biological entity in such a manner as to change an index of refraction of the sensing volume. The biosensor further includes a ring interferometer, one volumetric section of the ring interferometer being the sensing volume, a laser for supplying light to the ring interferometer, and a photodetector for receiving light from the interferometer.