Abstract: The invention relates to the field of devices for measuring a nonreciprocal effect and especially to the field of fiber-optic gyrometers. Disclosed a device for measuring a nonreciprocal effect comprising a light source, a monomode spatial filter, a Sagnac ring having two branches, a light splitter, and a light detector. The splitter is a polarization splitter. The filter is nonpolarizing. The detector includes a system for analyzing the polarization state. The light splitter devides the light over branches of the ring. The invention can be applied to other devices for measuring a nonreciprocal effect, especially fiber-optic magnetometers.

Abstract: Disclosed are a system and a method for determining coordinates of a three-dimensional measurer probe using a beam phase interference method. Two optical fibers are mounted inside the probe, and detecting means obtains an interference pattern generated by beam emitted from a point beam source mounted at ends of the optical fibers. After that, wave front of the interference pattern is measured and a location of the point beam source is determined through a nonlinear optimization from the wave front, and thereby the coordinates of the three-dimensional measurer probe are set. Because the two optical fibers of the inside of the probe to be measured are located in close vicinity to the three-dimensional object, the present measuring system and method can reduce a measurement error, make a structure of the system simple, and thereby reduce a manufacturing cost.

Abstract: The present invention provides a simple and direct method for the simultaneous correction of steady-state polarized fluorescence intensities, depolarized (or scrambled) by the effects of applied hydrostatic pressure without having to first determine the scrambling factors from a separate experiment. The method involves direct recalculation of the measured polarized data obtained for the sample of interest at the time of data collection.

Abstract: A spectroscope is provided with a point light source which emits a dispersed light having a plurality of wavelengths, a first optical system which collimates the dispersed light which is emitted from the point light source into an approximate parallel light flux, a dispersing element which disperses the approximate parallel light flux, and a second optical system for condensing the dispersed light flux near a focal plane. Aberrations for a plurality of wavelengths of an off-axial light flux are compensated in the second optical system. By doing this, it is possible to provide a spectroscope which has a high wavelength resolution.

Abstract: An interferometric fiber optic encoder readhead for sensing the displacement of a scale grating is disclosed. The detector channels of the readhead are fiber optic detector channels having respective phase grating masks. The fiber optic encoder readhead is configured to detect the displacement of interference fringes arising from the scale grating. In various exemplary embodiments, the fiber optic readhead is constructed and operably positioned according to various design relationships that insure a compact mounting and a relatively ideal sinusoidal signal as a function of displacement. Accordingly, high levels of displacement signal interpolation may be achieved, allowing sub-micrometer displacement measurements. The fiber optic encoder readhead may be assembled in a particularly accurate and economical manner and may be provided in a package with dimensions on the order of 1–2 millimeters.

Abstract: A heterodyne interferometer, adaptive optics system, method of measuring movement of a target and/or variations in a beam propagation medium, and method of controlling an adaptive optics system are provided. The heterodyne interferometer includes an acoustic-optical modulator that can superimpose a RF signal on a source signal, and output a zero order beam and a higher order beam. One of the beams comprises a target beam and the other beam comprises a local oscillator beam. A telescope can receive the target beam, and direct the target beam through the beam propagation medium to the target. A beam splitter can receive the local oscillator beam and the reflected beam from the target, and coherently combine the local oscillator beam and the reflected beam to produce a fringe pattern. A detector can receive the fringe pattern and generate an electrical beat signal, which can be demodulated based upon the RF signal.

Abstract: A device for holding measurement instruments (2), in particular interferometers, is formed from a plurality of structure elements (4, 5, 6, 7) connected to one another and made from at least one material. The at least one material has a very low coefficient of thermal expansion ?. The structure elements (4) on which the measurement instruments (2) are arranged are secured between at least two structure side parts (5) in such a way that the thermal expansions of the structure side parts (5) and of the connections (3) have no effect in the measurement direction of the measurement instruments (2).

Abstract: The optical properties of water impounded in reservoirs such as large tanks with closed covers and in uncovered reservoirs are monitored to detect harmful substances. The system and method comprises illuminating the water with an artificial light source within the enclosure for monitoring of the reservoir. Radiance and irradiance fluxes are measured by one or more multiband radiometers. Changes in radiance and irradiance are used to calculate spectral attenuation coefficients of the water. Fluorescence spectra are measured. A computer look-up table of known absorption and emission spectra is compared to the spectral attenuation to determine if a substance has been detected.

Abstract: An apparatus for cavity enhanced optical detection having an improved flow cell is provided. Sensitivity of the cavity resonance condition to changes in refractive index of an analyte flowing through the flow cell is reduced. More specifically, the round trip optical path defined by the resonant cavity intersects a curved cavity input mirror at a point. This point has a location on the input mirror that is substantially independent of the refractive index of the analyte. In this manner, changes in sample refractive index do not lead to misalignment of the resonant optical cavity.

Abstract: An optical property of a device under test is determined from a detected DUT response signal, or a signal derived therefrom, whereby the DUT response signal represents a signal response of the DUT in response to a composite signal or a signal derived from said composite signal. The composite signal comprises superimposed signals delayed with respect to each other.

Abstract: An achromatic shearing phase sensor generates an image indicative of at least one measure of alignment between two segments of a segmented telescope's mirrors. An optical grating receives at least a portion of irradiance originating at the segmented telescope in the form of a collimated beam and the collimated beam into a plurality of diffraction orders. Focusing optics separate and focus the diffraction orders. Filtering optics then filter the diffraction orders to generate a resultant set of diffraction orders that are modified. Imaging optics combine portions of the resultant set of diffraction orders to generate an interference pattern that is ultimately imaged by an imager.

Abstract: An interferometry method includes: imaging test light reflected from at least a first portion of a test surface to interfere with reference light on a camera and form an interference pattern, wherein the imaging defines a depth of focus for the light reflected from the test surface, and wherein the test light and reference light are derived from a common source; varying an optical path length difference between the test light and reference light over a range larger than the depth of focus, wherein the optical path length difference corresponds to a difference between a first optical path between the common source and the camera for the test light and a second optical path between the common source and the camera for the reference light; and maintaining the first portion of the test surface within the depth of focus as the optical path length difference is varied.

Abstract: An interferometry apparatus comprises one or more beam generators, a detector, and a plurality of optical paths along which one or more beams of light propagate. Disposed along at least one of the optical paths is an apodization mask to shape one of the beams.

Abstract: An integrated interferometric and intensity based microscopic inspection system inspects semiconductor samples. A switchable illumination module provides illumination switchable between interferometric inspection and intensity based microscopic inspection modes. Complex field information is generated from interference image signals received at a sensor. Intensity based signals are used to perform the microscopic inspection. The system includes at least one illumination source for generating an illumination beam and an integrated interferometric microscope module for splitting the illumination beam into a test beam directed to the semiconductor sample and a reference beam directed to a tilted reference mirror. The beams are combined to generate an interference image at an image sensor. The tilted reference mirror is tilted with respect to the reference beam that is incident on the mirror to thereby generate fringes in the interference image.

Abstract: A method disclosed in this specification is an aberration measuring method in which a light flux converged by a condensing optical system is made incident on a optical system to be measured, the light flux that has passed through the optical system to be measured is reflected by a reflecting optical system having a center of curvature at a light convergence point on a light emergence side of the optical system to be measured is made incident on the optical system to be measure again, and wavefront aberration of the optical system to be measured is detected as interference fringes using the light flux that has passed through the optical system to be measured again. Measurement is carried out while changing the numerical aperture of the optical system to be measured to a numerical aperture larger than a numerical aperture in the actual use, thereby realizing highly precise measurement of the wavefront aberration all over the effective numerical aperture of the optical system to be measured.

Abstract: The interferometer has a diffraction grating 21, a condenser lens 22, a transparent substrate 23, a field lens 24 and an imaging device 25 arranged in this order. The transparent substrate 23 is arranged at the position in the optical axis direction where both focal spots of a zeroth-order diffracted light L21 and a first-order diffracted light L22 are formed. Formed on the transparent substrate 23 is a circular opaque zone 23a whose central position is the central position of the focal spot of the first-order diffracted light L22. Formed at the center of the opaque zone 23a is a pinhole 23b whose central position is the central position of the focal spot of the first-order diffracted light L22. The contrast of the interference fringes observed on the image device 25 is enhanced by the optical interference between the first-order diffracted light L22 passing through the pinhole 23b and the zeroth-order diffracted light L21 passing through the transparent substrate 23.

Abstract: A microscope capable of being shaped into a beam with complete hollow shape by removing the disorder of the wavefront to the erase light, particularly, and capable of improving the spatial resolution by inducing a super-resolution near the limit, is provided.

Abstract: An apparatus for presenting a sample of material for analysis by a laser-based analyzer comprises a chamber, a first window for admitting laser radiation to the chamber, sample presentation means for presenting a sample such that said laser radiation can impinge upon the sample, and a plurality of second windows (76,78,80,82) for receiving radiation emitted from the sample, said plurality of second windows (76,78, 80,82) adapted to pass radiation emitted from the sample to a plurality of detector means. The apparatus further includes a gas inlet (98) and a gas outlet (100) to enable the atmosphere inside the chamber (52) to be controlled.

Abstract: Disclosed herein is a spectrophotometer at least including: an optical waveguide; a light entrance slit provided at an end face on the inner side of the optical waveguide, for bringing an incident light into the optical waveguide; an optical element provided at an end face on the inner side of the optical waveguide or at an interior of the optical waveguide, for separating the incident light brought in the optical waveguide into a spectrum; and a photoelectric conversion device provided at an end face on the inner side of the optical waveguide, for detecting the incident light separated into the spectrum at the optical element; wherein the optical waveguide, the light entrance slit, and the optical element being integrally formed on an optical waveguide board, and a photoelectric conversion device substrate having the photoelectric conversion device formed thereon being mounted on the optical waveguide board.

Abstract: An optical device has a rotatable birefringent crystal. The crystal is rotatable around a first axis (4; 42) and has a crystallographic-optical axis (6; 44) in a plane that is perpendicular to the first axis. In addition, the crystal is rotated around the first axis in order to control a displacement (?x) of a light beam in the plane when the light beam is polarized within the plane and directed onto the crystal.