Abstract: A plasma probe enables simultaneous localized electrostatic measurements and optical emission spectroscopy. The probe has a support arm with an elongated longitudinally extending section and a bend section at the end of which is supported an electrical probe element composed of back-to-back charge collection plates separated by an insulating spacer. The inner plate faces an opening in the end of the elongated support arm section which defines a collimating channel. An optical fiber extends through the support arm and has an aperture in the collimating channel to receive light emitted from the plasma between the end of the elongated section of the support arm and the inner charge collection plate. The electrical probe element acts as a blocking element to block light emitted from the plasma outside of the region between the electrical probe element and the end of the support arm section.

Abstract: An apparatus and method identify at least one attribute of an article for use in accurately reproducing the article. The apparatus includes at least one detector having an array of cells. At least one cell, in the detector array, the sensor cell, is provided with an extra colored coating or is painted with an extra color. When the article is scanned by the detector, the at least one sensor cell will read a different color value from the other cells due to the extra coating applied to it. The color that the at least one sensor cell would have output without the extra coating is interpolated from the detection results of the neighboring cells. This color and the color actually detected by the at least one sensor cell are then input to a controller which determines the at least one attribute of the scanned article using a model, such as a neural network, an expert system, a fuzzy logic model, and the like. The controller performs appropriate processing based on the at least one determined attribute.

Abstract: A colorimeter for reading color bars of printed sheets or the like includes a longitudinally extending base including a paper stop along which a sheet to be tested for color may be positioned. An autonomously operating colorimeter head is moved along the base in a direction parallel to the edge of the sheet by means of an electric motor mounted on the base and driving an helical thread lead screw engaging an X-axis carriage supporting the head. The head is moved by operation of the lead screw in a direction parallel to the edge of the sheet, referred to as the direction of the X-axis. The head includes an electric motor and a Y-axis transport supporting an optics unit. The optics unit is moved within the head in a direction parallel to a Y-axis, extending perpendicularly to the X-axis. The optics unit is preferably a spectrophotometer including a rotating wheel provided with a plurality of individual filters, spaced apart along the periphery of the wheel.

Abstract: A spectrograph for analyzing the chemical composition of a sample is disclosed. Scattered light from a sample cell is collected by one or more optical fibers and is introduced into a collimating lens as a linear optical signal. The collimating lens directs the optical signal to a reflective diffraction grating which reflects the signal into a focusing lens. The focusing lens focuses the optical signal onto a charge coupled device array which converts the optical signal into a electronic signal. Aberration correction is provided by the collimating and focussing lenses. The electronic signal is analyzed and converted by computer into a representation of the chemical analysis of the sample stream.

Abstract: A method and system are provided for suppressing or filtering multiple reflections which corrupt photometric (grey scale or color) or height measurements within optical systems such as imaging systems. The reflections may originate within the instrument (i.e. back reflections) or may be inter-reflections between one or more surfaces in a scene. In one embodiment, a beam of electromagnetic energy generated by a source is polarized in a first rotational sense, is transmitted to a point of interest (i.e., scene) of an object, is reflected and received by a receiver having a polarizer which passes reflected electromagnetic energy having a second rotational sense opposite the first rotational sense. In this way, unwanted reflections from the point of interest having the first rotational sense are suppressed and back-reflections to the source of electromagnetic energy are substantially eliminated.

Abstract: The present invention involves a combination of active and passive optical or opto-electronic device alignment techniques. Passive alignment is used for two axial lateral directions and all three axial rotational directions (yaw, pitch and roll). In such passive alignment, only the substrate is micromachined with passive alignment structures. One-dimensional active alignment is then used for the remaining axial lateral direction.

Abstract: A target device for use in aligning a target station to a reference line-of-sight established by a laser alignment beam is mountably secured to the target station. The target device includes a tooling tube and a beam splitter for reflecting a portion of the alignment beam to a focusing objective. The focusing objective transmits the portion of the alignment beam to a position sensing detector for alignment measurement. The target device is designed to pivot about a target mount center reference point located in the tooling tube. The focusing objective and the beam splitter focus the image of the position sensing detector at the target mount center to produce a virtual image of the position sensing detector at the target mount center. By taking the alignment measurement at the target mount center, inaccurate measurements created by misalignment of the tooling tube with respect to the alignment beam are eliminated.

Abstract: An apparatus for measuring a spectral characteristic of a fluorescent sample, being provided with: a first illuminator for emitting a beam in a wavelength range including the ultraviolet spectrum; a second illuminator for emitting a beam in a wavelength range longer than a first cutoff wavelength; a spectral radiance factor measuring device for measuring first and second total spectral radiance factors of a fluorescent sample by illuminating the fluorescent sample by the first illumination device and second illumination device, respectively; a memory for storing weight coefficients for weighting first and second total spectral radiance factors; and a calculator for calculating a total spectral radiance factor of the fluorescent sample in accordance with the following equation using measured first and second total spectral radiance factors and a weight coefficient:B.sub.t (.lambda.)=A(.lambda.).multidot.Bt.sub.1 (.lambda.)+{1-A(.lambda.)}.multidot.Bt.sub.2 (.lambda.)wherein:Bt(.lambda.

Abstract: A chemically and mechanically robust optical Raman spectroscopy probe assembly that can be incorporated in a cone penetrometer (CPT) for subsurface deployment. This assembly consists of an optical Raman probe and a penetrometer compatible optical probe housing. The probe is intended for in-situ chemical analysis of chemical constituents in the surrounding environment. The probe is optically linked via fiber optics to the light source and the detection system at the surface. A built-in broadband light source provides a strobe method for direct measurement of sample optical density. A mechanically stable sapphire window is sealed directly into the side-wall of the housing using a metallic, chemically resistant, hermetic seal design. This window permits transmission of the interrogation light beam and the resultant signal. The spectroscopy probe assembly is capable of accepting Raman, Laser induced Fluorescence, reflectance, and other optical probes with collimated output for CPT deployment.

Abstract: In a process for choosing a color most closely replicating an object's actual color, a computer processor programmed with a database of sets of digital color data and the corresponding formulas for producing those colors using one or more thermal transfer foils, or vinyl sheet materials, is provided. The process includes sensing an object's color and producing a set of digital color data representing the sensed color. The set of digital data representing the sensed color is then supplied to the computer processor which is operated to compare the supplied set of digital color data to the digital color data stored in the database. The computer processor then outputs, to a display, a listing of the closest color matches found in the database, to the sensed color. The user then selects the color and formula defined by the digital information stored in the database corresponding to a color producible using thermal transfer foils or vinyl sheet materials, to that most closely matching the sensed color.

Abstract: An automatic control system comprises a construction machine provided on a construction site and equipped with a ground leveling implement and a target; a survey unit for projecting a beam of tracking light toward the target and receiving reflected tracking light from the target to determine a coordinate position of the target; a storage unit for storing finished-plane height data corresponding to coordinate positions; a computation unit for determining a finished target height at the coordinate position of the target and for computing a deviation between the finished target height and a measured target height; and a transmitter for transmitting the deviation toward the construction site. The survey unit operates in a finished-height data drive mode in which the tracking light is moved vertically so that the height of the tracking light at the horizontal coordinate position is at the finished target height.

Abstract: Disclosed is a laser level device that includes a reference surface, and a laser beam generator that is coupled to the reference surface. The laser level device also includes a compensator that is supported proximate to the reference surface. The compensator has a pendulum that includes a polygonal body with at least a four point suspension. The compensator also has optics that are coupled to the polygonal body in the path of a laser beam that is produced by the laser beam generator to redirect the laser beam, and a keeper that is coupled to the reference surface and is at least partially surrounding the polygonal body such that an air gap may be provided between the polygonal body and the keeper. The laser level device further includes a beam sweeper that is supported above the reference surface in the path of the redirected laser beam to sweep the redirected laser beam in a plane.

Abstract: A grade measurement device for use with a transmitter operable to produce a radiant energy beam. The grade measurement device includes a base and a support member. The support member is movably coupled to the base. A detector operable to detect the radiant energy beam is disposed on the support member at a selected position. The detector is also operable to indicate detection of the radiant energy beam. A connection mechanism couples the support member and the base.

Abstract: A method for characterizing a sample includes the steps of (a) providing a semiconductor material; (b) applying at least one of an electric field, a pulsed or cw light source, a change in temperature and/or a change in pump pulse intensity to the semiconductor material; (c) absorbing pump light pulses in a portion of the semiconductor material and measuring changes in optical constants as indicated by probe light pulses applied at some time t following the absorption of the pump light pulses; and (e) associating a measured change in the optical constants with at least one of a surface charge, dopant concentration, trap density, or minority carrier lifetime.

Abstract: A Raman chemical imaging system uses a laser illumination source for illuminating an area of a sample. The spectrum of scattered light from the illuminated area of the sample is collected and a collimated beam is produced therefrom. An Evans Split-Element type liquid crystal tunable filter (LCTF) selects a Raman image of the collimated beam. A detector collects the filtered Raman images which are subsequently processed to determine the constituent materials. The Evans Split-Element-type LCTF suitable for high-definition Raman chemical imaging is incorporated into an efficient Raman imaging system that provides significant performance advantages relative to any previous approach to Raman microscopy. The LCTF and associated optical path is physically compact, which accommodates integration of the LCTF within an infinity-corrected optical microscope. The LCTF simultaneously provides diffraction-limited spatial resolution and 9 cm.sup.

Abstract: A method and apparatus for determining an axial relationship by viewing a target with an image inverter and determining the relationship of the optical axis of the image inverter relative to the position of the target by comparing the inverted view against another view. The image inverter can act as level by comparing the inverted image with a direct view of the target, or can measure an angle defined by the first target, the image inverter and a second target offset along a second axis. A mirror associated with the image inverter can provide a reflection of the second target along the reflective axis of the mirror, thus providing a measurement of the angle defined by the intersection of the reflective axis and the optical axis. Each target can comprise a bar, which can divide two contrasting portions to clarify the comparison of the inverted image and the direct or reflected image. The bar can be oriented horizontally or vertically, or at any appropriate orientation to support survey of angles or lines.

Abstract: A portable spectrophotometer includes a rotating wheel provided with a plurality of filters having filter characteristics in the 400 to 700 nanometer wavelength range. The filters are moved between an optical conduit and a photoelectric sensor as the wheel is rotated. In one embodiment, a lamp housing contains three object illuminating lamps circumferentially spaced apart by 120.degree. and projecting light onto the object sample at a 45.degree. angle to the object sample. Light reflected from the object sample is conducted through the optical conduit and focused on the optical sensor by means of a focusing lens. A blocking filter is interposed between the lens and the wheel and serves to block light outside of the 400 to 700 nanometer wavelength range. A side sensor receives light from one of the three lamps through the filters as the wheel is rotated and provides output signals which are used as reference signals for the individual filters.

Abstract: An apparatus and method for in situ spectral measurement is disclosed. The apparatus uses a low-resolution grating to disperse light and thereby image a spectrum thereof. The imaged spectrum is converted into a digital electrical signal and is processed in order to enhance the spectral information. The resulting spectral information is analogous to that captured using a higher resolution spectral imager with optical processing of the spectral data.

Abstract: Methods for wavelength determination of a monochromatic light beam are described. The methods involve a detector unit containing at least one pair of photo detectors. One of the detectors in each detector pair is covered with a variable attenuator and the other is not covered by the variable attenuator. The optical transmission coefficient of the variable attenuator is a monotonic function of wavelength. Under illumination of a monochromatic light, the photocurrents produced in the detectors with and without the variable attenuator are compared. The relative values of the photocurrents are used to determine the wavelength of the monochromatic light.

Abstract: The present invention involves a combination of active and passive optical or opto-electronic device alignment techniques. Passive alignment is used for two axial lateral directions and all three axial rotational directions (yaw, pitch and roll). In such passive alignment, only the substrate is micromachined with passive alignment structures. One-dimensional active alignment is then used for the remaining axial lateral direction.