Abstract: A distance measurement device of the present invention detects a subject image with separation from the background and determines the distance to the subject regardless of backlit or forelit situations. In the distance measurement device, the subject is imaged onto two sensor arrays through different optical paths having parallax. The displacement of one of image signals output from the sensor arrays relative to the other is detected to determine the distance to the subject. On the basis of output signals of the sensor arrays, an object detector unit in a CPU determines a main area in the entire area of each sensor array which is occupied by the main subject image. On the basis of output signals from the main area in each sensor array detected by the object detector unit, a correlation operation unit calculates the displacement of the subject image on one sensor array relative to the subject image on the other sensor array.

Abstract: An atomic absorption photometer with a hollow cathode lamp and a deuterium lamp uses for each a power source which receives a variable current and switches it on and off so as to output a constant voltage.

Abstract: An objective lens holder that holds an objective lens that directs a laser beam onto a disk is formed of a permanent magnet. Yokes are arranged at the periphery of the objective lens holder, with a focus coil and tracking coil fixed to them. One end of a wire-shaped flexible body is connected to one side face of the objective lens holder, the objective lens holder being thereby suspended and supported. Since the objective lens holder has applied to it displacement components with five degrees of freedom, excluding the axial direction of the flexible body, tilting of the optical axis of the objective lens can be generated. Consequently, coma aberration of the objective lens is reduced and high density recording and reproducing can be achieved.

Abstract: A method and an apparatus for determining the coverage of the interface between a liquid first phase and a liquid or gaseous second phase by at least one molecular species, at least the following procedural steps being carried out successively: the generation of a stream of droplets which contain at least the liquid first phase, in such a way that the droplets move along a droplet trajectory, and the non-contact determination of a measure of the coverage of the interface by the at least one molecular species at at least two different points along the droplet trajectory.

Abstract: A system (10, 110, 210) for detecting particles (144) on a surface of a substrate-supporting chuck (14, 114, 214) including an inspection subsystem (128, 130, 131, 116, 250, 252, 222, 216) for analyzing the surface of the chuck (14, 114, 214) to determine if any particles (144) are thereon, a movable table (16, 116, 216) for holding the chuck (14, 114, 214) to inspect it and for moving the chuck (14, 114, 214) during inspection, and a control unit (22, 122, 222) for moving the movable table (16, 116, 216) relative to the inspection subsystem (128, 130, 131, 116, 250, 252, 222, 216) to inspect the surface of the chuck (14, 114, 214) and to produce an indication signal if a particle (144) is detected on the surface of the chuck (14, 114, 214).

Abstract: A compact portable instrument for determining the percentage concentration of a material in a solution such as the amount of concentrate in an output from an Aqueous Film Forming Foam generator used to extinguish fires. The instrument comprises a refractive index sensor with a reflective type refractometer prism having a measuring surface in contact with liquids placed in a sample holder formed by an opening through a retainer plate. The measuring surface of the prism covers that opening and presses the retainer plate towards an outer surface of the instrument, that outer surface having entrance and exit ports for sample liquids at that opening. The refractometer senses the refractive index of liquid in the sample holder and, when properly calibrated, provides an output to a digital display that directly indicates the percentage concentration of material in the liquid.

Abstract: Apparatus for determining the level of fluid in a vessel comprises a fixed optical emitter for emitting light into the vessel, a light steering means for steering light emitted by the fixed optical emitter, the light steering means for steering the light to reflect from a surface of one of the vessel and a substance within the vessel, a window for receiving the steered light prior to transmission to the vessel, a detector for receiving light from the vessel, and a processing system for determining distance from the vessel or substance in accordance with a predetermined geometric relationship. The apparatus may additionally comprise a level for determining a number of degrees out of plumb of the vessel. Also, the apparatus may comprise an acoustic transmitter and receiver for determining the depths of first and second liquids in the vessel which are immiscible in one another.

Abstract: A lens distortion measurement system has a first grating of a first pitch on a transparent support such as a quartz reticle. The reticle is disposed between an illumination source and the lens system whose distortion is to be measured. An image sensor is provided within the image projection field of the lens system. A second grating of a second (different) pitch is provided on another transparent support, disposed between the lens system and the image sensor. Optionally, a relay lens is disposed between the second support and the image sensor. Illumination propagates from the illumination source through the first support, through the lens system, through the second support and is incident on the image sensor. The illumination forms a Moire fringe having a pitch orders of magnitude greater than the pitches of the first and second gratings.

Abstract: A light-measuring device is disclosed for continuously and accurately measuring the intensity of light beams of from low intensity to high intensity. The intensity of a light beam to be measured is measured by a photodiode. A bias voltage is applied to the photodiode by a bias power source to improve the saturation characteristic. When the measured light beam is of high intensity, an analog switch and a photo MOS relay are switched on. When measuring a light beam with medium intensity, only the analog switch is turned off and a bias voltage is not applied to the photodiode. When measuring a light beam with low intensity, the bias voltage is not applied to the photodiode by switching off the photo MOS relay.

Abstract: The present invention provides a dimensioning system for determining the minimum size box necessary to enclose an object traveling on a moving conveyor. The dimensioning system is comprised of a light source which generates a scan beam that is moved by a mirrored wheel. A line scan camera whose field of view tracks the moving scan beam receives images of the scan beam and outputs a signal which is processed to compute a three dimensional box structure of the scanned object.

Abstract: A system for locating sources of degradation of an optical path of an optical transmission system comprises means for transmitting (1) along the path a test pattern signal having a frequency spectrum predominately in a band below a data traffic rate means (4) for recovering the test pattern at a plurality of separate points in the path means (4) for determining an amount of pattern degradation from the shape of the recovered pattern, and means (5) for comparing the amounts of pattern degradation at the separate points to locate the source. A broad range of types of degradation can be detected efficiently, and the results used to take corrective action.

Abstract: A system for performing vertical spectrophotometric determinations uses a vessel which has an upper transparent surface and a lower transparent surface which are spaced apart to define a known fixed pathlength through which a light beam is transmitted. The vessel also includes a portion disposed above the upper surface which may be a spout having an opening for allowing the introduction of substances into the containment portion.

Abstract: An energy beam threat discrimination system (110) adapted for use with laser beam energy (134). The system (110) includes an first detector (114) for detecting a first laser signal. A second detector (112) detects a coherent laser signal. A timer circuit (124, 126) establishes a time interval between the detection of the first laser signal and the detection of the coherent laser signal and provides an output (130) in response thereto. A control circuit (128, 130) determines, based on the output (130), if the first laser signal and/or the second laser signal is threatening. In a specific embodiment, the first detector (114) provides an event detection flag (118) as an output in response to the detection of a first laser signal. The first detector (114) includes a high sensitivity laser light detector (142), a pre-amplifier (144), and an analog threshold circuit (146). The coherent detector (112) provides a coherent detection flag (116) as an output in response to the detection of the coherent laser signal.

Abstract: A system and method in which the chromatic dispersion characteristic, as a function of distance along a section of transmissive fiber, is measured. First and second optical signals are launched into a fiber under test to thereby generate, by a four-wave mixing process in the fiber, a probe signal. Because of a wave-vector phase mismatch, the probe signal power oscillates with a spatial frequency that can be measured as a function of distance in the fiber. The intensity oscillations are measurable as, for example, temporal variations in the Rayleigh backscattered light detected at the input end of the fiber. According to the present invention, the dispersion parameter at one or both of the first and second optical signal wavelengths, as a function of length along the fiber, is derived directly from these intensity oscillation measurements. From this information, it is possible to further derive maps at other wavelengths of interest.

Abstract: The collection of spectral information is enhanced through the formation of multiple zones of excitation and emission. In one embodiment, a plurality of the zones are located within a sample substance, thereby increasing the efficiency of sample spectrum collection. In another embodiment, a reference substance is positioned so as to enclose at least one of the excitation/collection zones. The reference substance adds a known spectrum to the collection path, enabling analytical instrumentation to compare the sample and reference spectra for calibration purposes. In a further embodiment, one of the zones may be positioned within a sealed volume, and compositional changes in the sealed volume may be detected and used for leak-detection purposes.

Abstract: A birefringence measuring apparatus 30 measures a birefringence of a transparent substrate D1 of an optical disc D having a reflective layer D2 thereon by detecting a reflected light beam L2, which is a reflection of a light beam L1 from the disc. The light beam irradiates the disc at an incident angle of ".alpha.", penetrates the transparent substrate, and reflected by the reflective layer. The light beam emitted from a light source 1 has a coherence length shorter than an optical path length P which is a sum of optical paths P1 and P2. The optical path P1 is a distance from the surface of the transparent substrate to the reflective layer, and the optical path P2 is a distance from the reflective layer to the surface of the transparent substrate.

Abstract: In a method and apparatus for evaluating the performance characteristics of fiber-optic endoscopes, a beam of light defining a predetermined intensity pattern is transmitted through the endoscope from a tip end through an eyepiece end of the endoscope. The intensity pattern of the beam defines either a uniform intensity, or an intensity which varies sinusoidally in a predetermined direction across the beam. The following tests are performed in order to evaluate both the optical fibers and the lens system of the endoscope, and the intensity pattern is selected in accordance with the requirements of the respective test: (i) a light loss test, (ii) a reflective symmetry test, (iii) a lighted fibers test, (iv) a geometric distortion test, and (v) a MTF test. A video system generates signals indicative of the optical intensity of the beam after transmission through the endoscope at each of a plurality of predetermined locations within the beam.

Abstract: A fixed optic sensor system (200) comprising a sensor system (210), and electronic sub-system (205) and a communications means (215). The system can be used for detecting the presence of various sample (236) properties and in that regard has widespread application by leveraging off various miniaturized sensor configurations including surface plasmon resonance (50), fluorescence (80), light transmission (125) and others (150). In one embodiment, the communications means (215) is a wireless transmitter/receiver. In another embodiment, a hand held instrument (358) can be used on-site and communicates with the sensor (350) to receive sample (352) related data and transmit it to a remote processing system (370) for further analysis. In yet another embodiment, a hand held instrument (403) has a plurality of cardiac marker binding ligands (400) deposited on the sensor/sample interface providing a medical diagnosis and point-of-care device (403).

Abstract: A mean optical power controller that controls power using a voltage controlled optical attenuator (VCOA) is disclosed. This controller uses a control loop in which a signal indicative of the present optical power level is compared to a signal indicative of the desired optical power level, with the difference then being used as input into the VCOA. This controller generates the required variety of signals indicative of the desired optical power level, or reference signals, without having to rely on a CPU. It does this by storing in a local storage means the voltage-values of the reference signals required to realize each supported user-defined optical power level. During the operation of the controller, the voltage-value corresponding to each selected power-level is passed to one or more DACs, where it is converted into a reference signal.

Abstract: An apparatus and method for simultaneously testing a plurality of optical fibers, preferably using optical time domain reflectometry, wherein the apparatus includes a light source for providing a pulse of light, at least one splitter means positioned for receiving the pulse of light and for splitting the pulse of light into at least two substantially identical pulses of light, and a plurality of coupling means, each connected to one of the optical fibers under test and each positioned for receiving one of substantially identical pulses of light and directing that pulse of light into an optical fiber. In a preferred embodiment, the backscattered signals from the optical fibers are directed back through the coupling means to a plurality of receivers and data averagers.