Abstract: The invention relates to a substantially transparent container for liquids on one side of which are opaque light and opaque dark areas of color observable through the container for evaluating contained liquid for particulate impurities. The container is particularly useful for pharmaceutical liquids.

Abstract: A pulsed electromagnetic radiation (EMR) source and an interferometer are used to obtain spectra from the surface of a sample. The pulsed EMR source uses a broadband radiation source and a monochromator to generate monochromatic radiation. Alternatively, a tunable laser can be used as the monochromatic radiation source. The modulated radiation impinges on the surface of interest where it is absorbed. The absorption of radiation causes the surface of the sample to expand. This change in dimension is then detected by an interferometer which employs a monochromatic radiation source to measure the instantaneous distance between the sample surface and the interferometer. The detection system of the interferometer can be an imaging device such as a video camera to obtain the spatial distribution of chemical composition of the sample surface.

Abstract: An optical interferometer system is described which precisely measures the angle of rotation of a mirrored surface about a desired axis of rotation without sensitivity to rotation of the surface about an axis perpendicular to the desired axis of measurement. Measurements of the angle or position of a surface are made without attaching any optical or other components to the surface. In operation, a laser beam is passed through a beam splitter which provides two secondary beams. Each of the beams is then passed through a respective optical assembly, each of which is essentially a mirror image of the other. Each of the optical assemblies comprises a unique combination and arrangement of optics which provides a folded optical path wherein the laser beam passes through the system optics and is reflected multiple times by the mirror being measured. Each of the beams then passes back through its respective optical section and is detected by optical means.

Abstract: A gas sample chamber that is particularly advantageous for use with a semiconductor laser has the form of an elongated hollow tube with a specularly reflective inside surface, a semiconductor laser located at one end of the tube and a detector located at the opposite end of the tube. In one embodiment, apertures in the wall of the tube permit a gas to enter and leave the sample chamber by free diffusion. In another embodiment the gas flows into the hollow tube from a pressurized source through a port or is drawn through the tube by a suction pump. In other embodiments, the tube is partitioned into two successive sections by means of a window located within the tube. The window is transparent to radiation of two different wavelengths that coincide with the absorption bands of two different gases. The semiconductor laser is tuned to these wavelengths successively so that two gas components can be detected and measured simultaneously.

Abstract: An interferometer is provided which includes a source for generating a source beam of linearly polarized coherent light along a light path; a non-polarizing beam splitting, combining and resplitter disposed in the path of the source beam for splitting the source beam into a reference beam and a measuring beam and for recombining the reference and measuring beams into an interfering beam and resplitting the interfering beam into a first output beam and a second output beam; a reference reflector positioned in the reference beam for causing the reference beam to traverse a reference path and return to the non-polarizing beam splitting means; a measuring reflector spaced a distance to be measured from the non-polarizing beam splitter for causing the measuring beam to traverse a measured path and return to the non-polarizing beam splitter; a half wave plate in one of the reference and measuring beams for rotating the polarization of the measuring beam relative to the reference beam prior to recombining the measur

Abstract: A luster detector arranged such that an output light beam of an LED is applied to a surface through a light projecting lens as an irradiating light beam having a predetermined width. Rays of light reflected from the surface are applied through a condenser lens to a line sensor. Of the rays of light reflected from the surface, the rays of light reflected regularly form a light spot on a light detecting section extending in the longitudinal direction of the light detecting section. Hence, even if the light receiving position is shifted, the light detecting operation is positively achieved. A detecting circuit determines the light reception distribution of the sensor to detect the luster of the surface.

Abstract: The present invention is a method for analyzing irregular-shaped chunked silicon for low-level contaminates. The method comprises selecting a zonable-chunk of silicon and float-zoning the chunk of silicon to effect a distribution of surface contaminates into the bulk of a monocrystal of silicon. The float-zoned monocrystalline silicon is then processed into a wafer suitable for analysis for low-level contaminates.

Abstract: An interferometer used as a rotation sensor is constructed using a strand of optical fiber, a portion of which is formed into a sensing loop. A pair of light waves are caused to counterpropagate in the sensing loop and are combined to form an optical output signal that has an intensity that varies in accordance with the difference in the phases of the two counterpropagating light waves. A phase modulator is positioned on the optical fiber in the sensing loop at a location such that the two counterpropagating light waves are modulated approximately 180 degrees out of phase. The time-varying phase modulation causes a time-varying phase difference that is combined with a rotationally-induced Sagnac effect phase to provide a total phase difference that is detected by a photodetector. The photodetector provides an electrical output signal that is processed to determine the Sagnac phase difference. The rotation rate is then calculated from the Sagnac phase difference.

Abstract: A method of profiling a rough surface of an object includes moving the object along a z axis so that a highest point of the rough surface is optically aligned with and outside of the focus range of a solid-state imaging array. An interferogram of the rough surface then is produced by means of a two beam interferometer. The solid-state imaging array is operated to scan the rough surface along x and y axes to produce intensity data for each pixel of the solid-state imaging array for a plurality of frames each shifted from the other by a preselected phase difference. The modulation for each pixel is computed from the intensity data. The most recently computed modulation of each pixel is compared with a stored prior value of modulation of that pixel. The prior value is replaced with the most recently computed value if the most recently computed value is greater.

Abstract: A system and method for generating a desired displacement of an object, i.e., a target, from a reference position with ultra-high accuracy utilizes a Fabry-Perot etalon having an expandable tube cavity for resolving, with an Iodine stabilized laser, displacements with high accuracy and for effecting (as an actuator) displacements of the target. A mechanical amplifier in the form of a micropositioning stage has a platform and a frame which are movable relative to one another, and the tube cavity of the etalon is connected between the platform and frame so that an adjustment in length of the cavity effects a corresponding, amplified movement of the frame relative to the cavity. Therefore, in order to provide a preselected magnitude of displacement of the stage frame relative to the platform, the etalon tube cavity is adjusted in length by a corresponding amount. The system and method are particularly well-suited for use when calibrating a high accuracy measuring device.

Abstract: In a signal processing apparatus and method, original two-phase signals each having the possibility of amplitude fluctuation are received by an input portion. From the original two-phase signals received by the input portion, new two-phase signals are formed by a signal processing portion. The signal processing portion forms an intermediate stage two-phase signal and a phase component eliminated signal having the phase components of the original signals eliminated therefrom in parallel from the original two-phase signals, and eliminates the fluctuation component of amplitude by the offsetting process of respective ones of the two-phase signals and the phase component eliminated signal to thereby form the new two-phase signals. The new two-phase signals have a predetermined phase relation with the original two-phase signals. The new two-phase signals are output from an output portion. This specification also discloses a displacement detecting apparatus using such a signal processing apparatus.

Abstract: Angular motion sensor signals from an inertial integrating rate sensor are provided to a translation device that provides a translated output signal that is substantially the same as an input sensor signal translated in frequency by an amount equal to a reference frequency. The translated output signal is provided to a phase detector that provides a detector output signal indicative of phase differences between the translated output signal and a feedback signal. The phase detector output signal is provided to a voltage controlled oscillator which provides an oscillator output signal that is related to the phase detector output signal. The voltage controlled oscillator signal is provided to a counter that is capable of providing a count that is representative of a highly resolved measure of angular rotation. In addition, the counter is capable of providing the feedback signal that is related to the variable frequency output signal.

Abstract: A sequential demultiplexing receiver for a network of sensors (20) using spectrum modulation encoding, the receiver being essentially constituted by an integrated optical circuit comprising a substrate (34) that is birefringent or semiconductive on which there are formed mode couplers or mode converters (38) operating by the electro-optical effect and that are sequentially activated at high frequency to generate optical path length differences matching those of the sensors.

Abstract: A polarizing optical arrangement wherein a linearly polarized signal beam cluster is generated. The signal beam cluster is created from interfering partial beam clusters and is linearly polarized. The azimuth of oscillation of the linearly polarized signal beam cluster is dependent on the mutual phase relationship of the aforementioned partial beam clusters. A splitter grating splits the linearly polarized signal beam cluster into partial beam clusters that are analyzed by analyzers, detected by photoelectric transducers and phase-shifted electrically from one another.

Abstract: An interferometer used as a rotation sensor is constructed using a strand of optical fiber, a portion of which is formed into a sensing loop. A pair of light waves are caused to counterpropagate in the sensing loop and are combined to form an optical output signal that has an intensity that varies in accordance with the difference in the phases of the two counterpropagating light waves. A phase modulator is positioned on the optical fiber in the sensing loop at a location such that the two counterpropagating light waves are modulated approximately 180 degrees out of phase. The time-varying phase modulation causes a time-varying phase difference that is combined with a rotationally-induced Sagnac effect phase to provide a total phase difference that is detected by a photodetector. The photodetector provides an electrical output signal this is processed to determine the Sagnac phase difference. The rotation rate is then calculated from the Sagnac phase difference.

Abstract: A displacement information measuring apparatus comprising light emitting source for emitting two light fluxes, acoustic optical device for giving a predetermined frequency difference to the two light fluxes from the light emitting source, optical system having a diffraction grating upon which at least one light flux of two light fluxes having the predetermined frequency difference given by the acoustic optical device is vertically incident so that the light fluxes are diffracted, the optical system causing at least one light flux from the diffraction grating to be incident upon an object in which the displacement information is to be measured, and detector for performing a detection by interference of one light flux incident upon said object and emergent from said object with the other of the two light fluxes, the displacement information of the object being obtained from a beat signal corresponding to the frequency difference and obtained from the detector, wherein the optical system is constituted such that

Abstract: A remote seismic sensing system is provided which operates as a bipolarized, differential mode, LDI (laser differential interferometry) system to detect electrical signals produced at a remote location. In preferred embodiments, the system is used in seismic surveying to detect array signals. An amplified array signal (the electrical signal is coupled to an array retroreflector apparatus (target). The array signal is obtained from an array of seismic detectors, e.g., geophones or hydrophones. The amplified array signal increases the velocity of a Doppler shifting optical component on the target. The target converts a defused sensing beam into two polarized return sensing signals, both of the return sensing signals having been Doppler shifted by the target to contain frequency components that represent motions, e.g., ground motions and wind motions, that are common to both signals and to contain a difference signal which represents the array signal.

Abstract: An optical fiber surface plasmon resonance (SPR) sensor includes both a metal layer and an overlay or underlay material on its surface. Existing fiber based SPR devices are inherently incapable of monitoring aqueous systems which have a refractive index ranging between 1.33 and 1.35, and existing prism based SPR sensors have proved too cumbersome for online chemical and biochemical analyses. Inclusion of the overlay or underlay material on the SPR sensor allows monitoring media with a refractive index from 1.00 to the 1.39 barrier and above. Hence, the SPR sensor allows monitoring important biochemical and chemical aqueous processes where the media typically have a refractive index between 1.33 and 1.35. In operation, samples are simply applied to the sensing region of the SPR sensor where the metal layer and overlay or underlay materials are coated, introducing a polarized beam of light into the optical fiber, and detecting surface plasmon resonance.

Abstract: An interferometric fiber optic gyroscope employing an integrated, width pshed, optic chip containing annealed proton exchange waveguides and a Mach-Zehnder interferometer for sensing a ramp induced signal from loop closing electronics to achieve a highly improved gyroscope scale factor linearity and dynamic range. An edge light emitting diode (ELED) operating at 1.3.mu. wavelength is employed as the light source in the gyroscope. A decorrelator optical fiber segment is employed between the light source and the chip, and a Lyot depolarizer optical fiber segment is employed between the chip and one side of the fiber optic coil. Also, an intermediate output of the loop closing electronics is shown to have reduced scale factor sensitivity to light source wavelength change.

Abstract: A dual function readhead for a reflectance instrument is located in a housing for the instrument. A first light source for emitting radiation for reflectance readings and transmitting data is mounted in the readhead. In addition, a first photodetector is mounted in the readhead for detecting or receiving reflectance readings. A format or interface access port is defined in the readhead. An interface is provided that includes a second photodetector for detecting data transmitted by the first light source. A microprocessor is also provided for decoding data received by the second photodetector. A second light source may also be included with the interface for transmitting commands or data to the first photodetector. Software for controlling the operation of the first light source and the first photodetector is also provided.