Abstract: Scanning interferometer and method of using same providing for rapid, reliable detection of chemical compounds that are readily implemented in low-cost, portable configurations for application in a variety of monitoring and detection applications. A scanning double-beam interferometer, particularly a Michelson interferometer, in which the length of at least one of the optical paths (or arms) of the interferometer is selectively adjustable by use of an actuator in which rotational displacement of a rotatable element is converted into linear displacement of at least one reflective surface which forms an end of an optical path of the interferometer is employed to obtain interferograms of electromagnetic radiation attenuated, emitted, scattered or reflected from a sample. The length of the optical path that is adjusted is determined using an optical detection scheme, particularly where marking on the rotatable element are detected to determine linear displacement of the reflective surface.

Abstract: The invention relates to an interferometer, comprising at least a beam splitter (10), an end mirror (11) for returning beams (S2, S3), and a set of mirrors (12, 13, 14, 15) for reflecting the beams (S2, S3) between the beam splitter (10) and the end mirror (11), at least some of said mirrors (12, 13, 14, 15) being mounted on a rigid structure (17) which is arranged to be rotatable around an axis (A). Said set of mirrors comprises at least one pair of planar mirrors, constituted by two plane mirrors (12, 13), and two angular mirrors (14, 15), constituted by plane mirrors and arranged to deflect a course of the beam (S2, S3) hitting the angular mirror (14, 15) and to direct the beams (S2, S3), guided from the beam splitter (10) by way of at least one pair of plane mirrors (12, 13) to the angular mirrors (14, 15), to the end mirror (11) and back to the beam splitter (10).

Abstract: Probes, and systems and methods for optically scanning a conical volume in front of a probe, for use with an imaging modality, such as Optical Coherence Tomography (OCT). A probe includes an optical fiber having a proximal end and a distal end and defining an axis, with the proximal end of the optical fiber being proximate a light source, and the distal end having a first angled surface. A refractive lens element is positioned proximate the distal end of the optical fiber. The lens element and the fiber end are both configured to separately rotate about the axis so as to image a conical scan volume when light is provided by the source. Reflected light from a sample under investigation is collected by the fiber and analyzed by an imaging system. Such probes may be very compact, e.g., having a diameter 1 mm or less, and are advantageous for use in minimally invasive surgical procedures.

Abstract: A system for analyzing a thin film uses an energy beam, such as a laser beam, to remove a portion of a contaminant layer formed on the thin film surface. This cleaning operation removes only enough of the contaminant layer to allow analysis of the underlying thin film, thereby enhancing analysis throughput while minimizing the chances of recontamination and/or damage to the thin film. An energy beam source can be readily incorporated into a conventional thin film analysis tool, thereby minimizing total analysis system footprint. Throughput can be maximized by focusing the probe beam (or probe structure) for the analysis operation at the same location as the energy beam so that repositioning is not required after the cleaning operation. Alternatively, the probe beam (structure) and the energy beam can be directed at different locations to reduce the chances of contamination of the analysis optics.

Abstract: An interferometer spectrometer that has reduced alignment sensitivity is described herein. Parallelism of an output ray pair formed by a single input ray is not affected by variations in relative alignment of the components. In comparison to other compensated interferometer designs, lateral separation errors in the output ray pair due to optical component misalignment are reduced. The reduced alignment sensitivity may be accomplished by utilizing simple planar components that are common to both light paths. The reduced alignment sensitivity and simplicity in design provides a more compact and more robust interferometer, with reduced manufacturing costs associated therewith. An elliptical field of view light source that utilizes an array of collimator lenses is also described. The light source provides a more compact design than a single circular collimator lens of the same area, and is suitable for single channel or multi-channel use.

Abstract: A measuring apparatus comprising a measuring chip, an optical incidence system, a photodiode array, a differentiation part, and a computation part. The differentiation part differentiates an optical detection signal output from each light-receiving element, in a direction where light-receiving elements are juxtaposed, at intervals of outputs of two adjacent light-receiving elements. The computation part specifies a reference light-receiving element, then judges whether or not values of the optical detection signals of a first predetermined number of light-receiving elements increase monotonously in directions going to both sides, and computes a position of a dark line on the basis of a value obtained by differentiating the outputs of a second predetermined number of light-receiving elements sandwiching the reference light-receiving element when it is judged that the values of the optical detection signals increase monotonously, in the above-described direction.

Abstract: A multispectral selective reflection Lidar system generates alternating pulses of at least two wavelengths and senses returns for determining the presence of a predetermined material absorbing and reradiating one wavelength as selective reflections, but not the other. A detector can readily determine the presence or absence or an absorbing and reradiating return. The system is for preferred use as an orbiter sensor about a planetary body, such as a Jupiter moon, for determining the presence of organic material and for the relay of information back to earth.

Abstract: This invention is an apparatus for imaging metrology, which in particular embodiments may be integrated with a processor station such that a metrology station is apart from but coupled to a process station. The metrology station is provided with a first imaging camera with a first field of view containing the measurement region. Alternate embodiments include a second imaging camera with a second field of view. Preferred embodiments comprise a broadband ultraviolet light source, although other embodiments may have a visible or near infrared light source of broad or narrow optical bandwidth. Embodiments including a broad bandwidth source typically include a spectrograph, or an imaging spectrograph. Particular embodiments may include curved, reflective optics or a measurement region wetted by a liquid. In a typical embodiment, the metrology station and the measurement region are configured to have 4 degrees of freedom of movement relative to each other.

Abstract: A long life laser wavelength meter is based on a Michelson interferometer with a flexure scanner. The scanner has a bar, preferably balanced about a pivot axis defined by a flexural pivot which supports the bar. Retroreflectors are mounted on the bar, equally spaced from the pivot axis. Long life is obtained by cycling or oscillating the bar over a limited range of angular movement within the bending limits of the flexure, which obtains a predicted, essentially infinite cycle life of the flexure. A large optical path length change for each scan of the oscillating bar is obtained through the use of the retroreflectors which fold the optical paths of each arm of the interferometer before reaching a fixed end mirror. The end mirror directs each optical path back through the same set of optical components, including the retroreflectors, to a beamsplitter which combines the light beams from both paths creating an optical interference beam output to a detector.

Abstract: A modulated reflectance measurement system includes two lasers for generating a probe beam and an intensity modulated pump beam. The probe beam is in the visible spectrum and the pump beam is in the ultra-violet spectrum. The pump and probe beams are joined into a collinear beam and focused by an objective lens onto a sample. Reflected energy returns through the objective and is redirected by a beam splitter to a detector. A lock-in amplifier converts the output of the detector to produce quadrature (Q) and in-phase (I) signals for analysis. A processor uses the Q and/or I signals to analyze the sample.

Abstract: A tilt compensator and delay element for use in an interferometer. The interferometer can be a scanning or a non-scanning interferometer. For example, the interferometer can be a Michelson-Morley interferometer or a Mach-Zehnder interferometer having a scanning mirror. The tilt compensator and delay element removes the tilt effects of the scanning mirror in two axes. The interferometer receives light and passes the light through a beam splitter. The light passed through the beam splitter is reflected by at least two mirrors. The beam splitter and the mirrors are positioned in a first plane. The tilt compensator and delay element of the present invention is provided with an odd number of mirrors. The odd number of mirrors includes at least three mirrors. For example, the odd number of mirrors in the tilt compensator and delay element can include three mirrors, five mirrors, seven mirrors, nine mirrors, etc.

Abstract: A method and apparatus for performing optical microscopy in one to three dimensions employs a spectral self-interference fluorescent microscopy technique that includes providing at least one fluorescent microscopy sample (220a, 220b), at least one objective lens (201), and a reflecting surface (204). The fluorescent sample is disposed between the objective lens and the reflecting surface, the distance (d1, d2) from the sample to the reflecting surface is several to several tens times an excitation wavelength. Excitation light (216) causes the fluorescent sample to emit light (214), at least a portion (214b) of which is reflected by the reflecting surface. The objective lens collects both the reflected light and the light emitted directly by the fluorescent sample (214a). The direct and reflected light interferences causing spectral oscillations in the emission spectrum.

Abstract: The optical interferometer in which the incident light beam 3 is branched into 2 optical paths of the reflection light and the transmission light which cross at right angle with each other by the beam splitter 4, and on each optical path, the reflection light is totally reflected by the first reflection unit 5, and the transmission light is totally reflected by the second reflection unit 6, and the reflection lights by both reflection units 5 and 6 are wave-combined again by the beam splitter 4, and received by the light receiver 7. The beam splitter 4 by which the incident light beam is wave-separated and wave-combined, is arranged with a little inclination from the vertical to the incident light beam.

Abstract: An interferometer spectrometer that has reduced alignment sensitivity is described herein. Parallelism of an output ray pair formed by a single input ray is not affected by variations in relative alignment of the components. In comparison to other compensated interferometer designs, lateral separation errors in the output ray pair due to optical component misalignment are reduced. The reduced alignment sensitivity may be accomplished by utilizing simple planar components that are common to both light paths. The reduced alignment sensitivity and simplicity in design provides a more compact and more robust interferometer, with reduced manufacturing costs associated therewith. An elliptical field of view light source that utilizes an array of collimator lenses is also described. The light source provides a more compact design than a single circular collimator lens of the same area, and is suitable for single channel or multi-channel use.

Abstract: An optical part driving device for moving an optical part, comprises; a driving timing pulley, a pair of driven timing pulleys, a timing belt wound by the driving timing pulley and the driven timing pulleys and connected with the optical part between the pair of driven timing pulleys, and a pair of tension pulleys for tensing the timing belt on both sides of the driving timing pulley.

Abstract: An optical interferometer in which a reference light and a light to be measured interfere with each other includes a casing, a movable optical part which is movable with respect to the casing, a fixed optical part which is fixed to the casing, and an attachment emember for attaching the movable optical part to the casing and for removing the movable optical part form the casing.

Abstract: An interferometer spectrometer that has reduced alignment sensitivity is described herein. Parallelism of an output ray pair formed by a single input ray is not affected by variations in relative alignment of the components. In comparison to other compensated interferometer designs, lateral separation errors in the output ray pair due to optical component misalignment are reduced. The reduced alignment sensitivity may be accomplished by utilizing simple planar components that are common to both light paths. The reduced alignment sensitivity and simplicity in design provides a more compact and more robust interferometer, with reduced manufacturing costs associated therewith. An elliptical field of view light source that utilizes an array of collimator lenses is also described. The light source provides a more compact design than a single circular collimator lens of the same area, and is suitable for single channel or multi-channel use.

Abstract: A novel variation of Michelson's interferometer uses tilt- and shear-compensation optics to allow various mirror motions to produce variation of path difference. The tilt-compensation mechanism consists of two complementary reflections from a single plane mirror and, in some cases, the beamsplitter, to produce a beam having a constant angle of propagation, typically the same as the input beam. Using a retroreflector to invert the image of a single plane mirror or a sequence of plane mirrors before the second reflections produces complementary reflections. A particularly efficient embodiment of the present invention uses one or more balanced disk-shaped mirrors to effect very rapid variation of path difference by nutation or precession. Other advantages of tilt-compensation include photometric stability. This interferometer has applications in spectrometry, spectral imaging and metrology.

Abstract: An analytical method of qualitative and optionally quantitative determination of the occurrence of polymerization/coagulation in a fluid containing polymerizable/coagulable components is described. The method comprises the steps of directing incident beams of electromagnetic radiation through a transparent support on which a film of electrically conducting material is placed, to the back of the film, at angles equal to or greater than the critical angle for total reflection, and measuring changes in the reflected beams due to changes in the surface plasmon resonance angle. Repeated measurements are correlated to the occurrence and magnitude of changes with qualitative and optionally quantitative occurrence of polymerization/coagulation in the fluid. The analytical method is not volume dependent since only one (small) surface of the measuring instrument needs to be in contact with the fluid. Further, the method can also be applied to poorly transparent fluids such as blood.

Abstract: An instrument for determining spectral content of an input light. The instrument has a rotating optical element that separates an input light into two partial beams and thereby introduces a variable OPD between the partial beams. The instrument then records an interferogram as a function of the variable OPD and thereby Fourier or Fast Fourier transforms the interferogram into a spectrogram so that the spectral content of the input light is revealed.

Abstract: An interferometer device includes a first prism portion and a second prism portion. The first prism portion has a semi-transparent surface, a beam incident surface and a beam emerging surface. The beam incident surface receives an incident light beam at a wavelength of &lgr; and at an angle of incidence &thgr; with respect to a normal to the beam incident surface. The second prism portion has a surface that corresponds to the semi-transparent surface of the first prism portion and a beam emerging surface that corresponds to the beam emerging surface of the first prism portion. The first and second prism portions are attached to each other at the semi-transparent surface of the first prism portion and the surface of the second prism portion corresponding to the semi-transparent surface.

Abstract: An apparatus measures the diameter, relative concentration and weight of particles. The detection of scattered light produced when light is projected at particles drawn into a nozzle-shaped measuring space is used to measure particle diameter, particle concentration is measured based-on variations in the intensity of transmitted light, and particle weight is measured based on changes in operating frequency of a crystal oscillator resulting from the adhesion of particles on the surface of the crystal oscillator.

Abstract: An image processing apparatus for processing a half tone image comprises: an input device to input an image signal; an image forming circuit to form an image onto a recording medium such as a photosensitive drum on the basis of the image signal supplied by the input device; a generator to generate a plurality of image data having different densities; a density detector to detect a density of the image formed on the recording medium by the image forming circuit on the basis of the image data generated from the generator; and a forming circuit to form a plurality of density conversion coefficients to convert the density of the image signal supplied by the input device on the basis of the densities of the plurality of images which are detected by the density detector.