Abstract: In some embodiments, the pathlength difference (retardation) in a step scanning infrared (IR) spectrometer interferometer is maintained under AC servomechanism (servo) control for a first period following a step change, and under DC servo control for a second period following the first period. Data is acquired during and/or after the DC servo control period. Switching off the AC servo control prior to data acquisition allows limiting the dither-frequency noise that could otherwise affect signals of interest, particularly in fast-time-scale applications such as high-speed time-resolved spectroscopy (TSR). A mirror position control circuit controls a mirror position stepping as well as switching a mirror servo control from AC to DC.

Abstract: The present invention relates to a vibration-insensitive interferometer using a high-speed camera and a continuous phase scanning method. The interferometer measures a measurement target by completely isolating influences of externally occurring vibrations from a frequency domain. The interferometer includes a light source unit for emitting light. A light transmission unit radiates the light emitted from the light source unit to the measurement target, splits light reflected from the measurement target into reference light and measurement light, and allows the reference light and the measurement light to interfere with each other, thus generating an interference fringe. A continuous phase scanning unit for radiates the reference light split by the light transmission unit through continuous phase scanning.

Abstract: A temperature measuring apparatus includes a light source, a first splitter, a second splitter, a reference beam reflector, an optical path length adjuster, a reference beam transmitting member, a first to an nth measuring beam transmitting member and a photodetector. The temperature measuring apparatus further includes a controller that stores, as initial peak position data, positions of interference peaks respectively measured in advance by irradiating the first to the nth measuring beam onto the first to the nth measurement point of the temperature measurement object, and compares the initial peak position data to positions of interference peaks respectively measured during a temperature measurement to thereby estimate a temperature at each of the first to the nth measurement point.

Abstract: A vibration detection device that includes a light source that emits a laser beam; an interferometer, which includes two vibrating bodies that are capable of reflecting the laser beam, that splits the laser beam to cause interference patterns; and a detector that detects vibrations on the basis of the interference patterns.

Abstract: A first light beam and a second light beam having discrete wavelength bands are emitted form a light source unit, and enter a light divider. The light divider separates each light beam into a measuring light beam and a reference light beam. The measuring light beams are irradiated on a measurement target, and reflected light beams, which are reflected at various depth positions of the measurement target, are caused to enter a combiner. The reference light beams propagate through optical fibers to enter the combiner. Interference light beams formed by the reflected light beams and the reference light beams for each of the first and second light beams are photoelectrically converted into interference signals. A tomographic image is obtained employing the interference signals for each of the first and second light beams.

Abstract: An optical tomograph is equipped with: a light source unit for emitting a plurality of light beams, the wavelengths of which are swept within different predetermined wavelength bands respectively with the same period; light divider which divides each light beam into a measuring light beam and a reference light beam; light beam combiner which combines reflected light beams, which are the measuring light beams reflected by a measurement target when the measuring light beams are irradiated thereon, with a reference light. An interference light detector detects an interference light beam, which is formed by the reflected light beam and the reference light combined by the light beam combiner, for each of the light beams as an interference signal. A tomographic image processor generates a tomographic image of the measurement target employing the plurality of interference signals detected by the interference light detector.

Abstract: An instrument for use in a borehole, the instrument including a pressure tuned light source disposed in a housing adapted for insertion into the borehole.

Abstract: Image quality of tomographic images obtained by optical tomographic measurement is improved. Spatial frequency processes are administered on a tomographic image, with the frequency processing properties (high frequency gain) in the scanning direction of a measuring light beam set to be lower than the frequency processing properties (high frequency gain) in the direction of the optical axis of the measuring light beam. For example, a smoothing process that removes high frequency components is administered to the tomographic image only in the scanning direction. Alternatively, a sharpening process that emphasizes high frequency components is administered to the tomographic image only in the direction of the optical axis.

Abstract: A physical quantity measuring system according to the present invention comprises: an optical fiber having fiber Bragg gratings; a light source connected to the optical fiber; an arrayed waveguide grating connected between the light source and the optical fiber via an optical branching filter, and having output channels of which central wavelengths of at least three output channels are included in a one-tenth loss band of a reflected light by the fiber Bragg grating; light receiving devices for receiving light output from the output channels on a one-to-one basis; and a central reflected wavelength change detecting unit connected to the light receiving devices for estimating a change in a central reflected wavelength based on a physical quantity, by calculating first and second group signals from light receiving signals corresponding to the at least three output channels, and by calculating a differential signal between the first and the second group signals.

Abstract: Methods, systems, apparatus and devices for using a modified PDH technique to measure the FSR of an etalon with one part per 104 precision.

Abstract: There is provided a pointing device including a light source that provides incident light for illuminating a front surface of a substrate at a predetermined angle of incidence, the substrate having a rear surface as well as the front surface and being transparent to the wavelength of the incident light, a detector that detects the intensity of speckle light from the front and rear surfaces, the speckle light generated from the incident light, and legs that are in contact with the substrate and charge the front surface of the substrate through friction between the legs and the substrate.

Abstract: An environmental sensing device includes an interferometric modulator which permanently actuates, in a visually-detectable manner, in response to being exposed to a predetermined environmental threshold or condition. The device can include a reactive layer, coating, or proof mass disposed on a movable member of the interferometric modulator. The reactive layer, coating, or proof mass can expand, contract, bend, or otherwise move when exposed to a predefined chemical, level of humidity, temperature threshold, type of radiation, and/or level of mechanical shock, causing the interferometric modulator to collapse and permanently indicate such exposure.

Abstract: A system, arrangement, computer-accessible medium and process are provided for determining information associated with at least one portion of an anatomical structure. For example, an interference between at least one first radiation associated with a radiation directed to the anatomical structure and at least one second radiation associated with a radiation directed to a reference can be detected. Three-dimensional volumetric data can be generated for the at least one portion as a function of the interference. Further, the information can be determined which is at least one geometrical characteristic and/or at least one intensity characteristic of the portion based on the volumetric data.

Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An illumination system delivers the electromagnetic radiation to an object plane. A source of a diffraction pattern is in the object plane. A projection optical system projects the diffraction pattern onto an image plane, which includes a mechanism (e.g., a shearing grating) to introduce the lateral shear. A detector is located optically conjugate with the pupil of the projection optical system, and receives an instant fringe pattern, resulting from the interference between sheared wavefronts, from the image plane. The diffraction pattern is dynamically scanned across a pupil of the projection optical system, and the resulting time-integrated interferogram obtained from the detector is used to measure the wavefront aberration across the entire pupil.

Abstract: An optical tomographic imaging apparatus capable of obtaining a high resolution tomographic image rapidly. In the apparatus, light beams having different wavelength ranges with portions of the ranges overlapping with each other are outputted from light source units, each of which is split into measuring and reference beams in each of the beam splitting units. A reflected beam reflected from a measuring object when the measuring beams are irradiated onto the measuring object is combined with the respective reference beams in the respective beam combining units, and a plurality of interference beams generated when the reflected beam is combined with the respective reference beams is detected in the respective interference light detection units, thereby interference signals are generated and a tomographic image is generated using the generated interference signals.

Abstract: Arrangements and methods are provided for obtaining data associated with a sample. For example, at least one first electro-magnetic radiation can be provided to a sample and at least one second electro-magnetic radiation can be provided to a reference (e.g., a non-reflective reference). A frequency of such radiation(s) can repetitively vary over time with a first characteristic period. In addition, a polarization state of the first electro-magnetic radiation, the second electro-magnetic radiation, a third electro-magnetic radiation (associated with the first radiation) or a fourth electro-magnetic radiation (associated with the second radiation) can repetitively vary over time with a second characteristic period which is shorter than the first period. The data for imaging at least one portion of the sample can be provided as a function of the polarization state.

Abstract: A method and apparatus for estimating bandwidth of laser output light is described which may include a dispersive element producing a dispersed output having a plurality of spectrum images from at least a portion of the laser output light. An array of light detecting elements is oriented to receive the dispersed output together with a shifting mechanism that moves the array, the dispersed output, or both, relative to each other. Electronics may be provided for determining the widths of at least two spectrum images at different phases of registration between the spectrum images and light detector elements and for averaging the widths to estimate a laser output bandwidth. The-spectrum images formed by the laser output light may be under-sampled, e.g., in the spatial or time domains.

Abstract: An optical multilayer mirror of a Fabry-Perot interferometer includes a reinforcing section provided as a side wall of each of second and fourth high refractive-index layers. The reinforcing section is configured to support a portion of each of the second and fourth high refractive-index layers covering a top surface of each of first and second low refractive-index layers and reach first and third high refractive-index layers via each of the first and second low refractive-index layers, respectively. Even when the first and second low refractive-index layers lack a mechanical strength with a high n ratio achieved by selecting materials for the first through fourth high refractive-index layers and the first and second low refractive-index layers, the reinforcing section helps prevent the second and fourth high refractive-index layers from being bent. The optical multilayer mirror thus features a wide high-reflectance band.

Abstract: Apparatus and method for detecting the presence or amount or rate of binding of an analyte in a sample solution is disclosed. The apparatus includes an optical assembly having first and second reflecting surfaces separated by a distance “d” greater than 50 nm, where the first surface is formed by a layer of analyte-binding molecules, and a light source for directing a beam of light onto said first and second reflecting surface. A detector in the apparatus operates to detect a change in the thickness of the first reflecting layer resulting from binding of analyte to the analyte-binding molecules, when the assembly is placed in the solution of analyte, by detecting a shift in phase of light waves reflected from the first and second surfaces.

Abstract: A stroboscopic imaging interferometer system includes an environmental chamber having a novel viewing window equipped with a rigidly integrated beam splitter and piezo actuated reference mirror for illuminating a device providing an object beam and reference mirror for providing a reference beam, upon the reflection of both beams, produces interference of the object beam by the reference beam for providing absolute phase observations of the device, that may be a MEMS device under test.