Abstract: A stereo imaging based vision system to monitor the area on the two sides of either a door and control door motion according to the motion of 3D objects in the viewing area. The system calibrated to provide heights above the ground plane for any point in the field of view. Therefore, when any object enters the field of view, it generates interest points called “features”, the heights of which are measured relative to the ground plane. These points are then clustered in 3D space to provide “objects”. These objects are then tracked in multiple frames to provide “trajectories”. Such a system could then control the door motion (open, close, stall) based on the various pieces of information generated about the object.

Abstract: A stereo imaging based vision system is calibrated to provide heights above the ground plane for any point in the field of view. Therefore, when any object enters the field of view, it generates interest points called “features,” the heights of which are measured relative to the ground plane. These points are then clustered in 3D space to provide “objects.” These objects are then tracked in multiple frames to provide “trajectories.” Such a system could then control alarm signals or actuate gates or motion control devices, for example, based on the various pieces of information generated about the object.

Abstract: A two-dimensional (2-D) machine-vision safety-solution involving a method and apparatus for performing high-integrity, high efficiency machine vision. A known structured lighting texture pattern is projected upon a target area. A model image of the pattern on an empty target field is stored during an initial training step. The machine vision safety solution digitally interprets a camera image of the light reflected by the objects in the target area to detect and characterize a pattern in the image. The pattern characterization is then processed to determine if a distortion of the characterization factors is larger than a predetermined threshold, and results in an alarm condition.

Abstract: A freeze-thaw valve is provided using a Peltier heat pump where the thermal short-circuit path between a cooled thermal mass and a heated thermal mass is reduced or absent and the valve state transition time is minimized. The freeze-thaw valve comprises a Peltier heat pump mounted to a heat exchange surface that comprises a cross-drilled copper water jacket or manifold. The Peltier heat pump is operated to maintain a cooled thermal mass at a substantially constant low temperature. A resistance heating element is used to produce a heated thermal mass. The freeze-thaw segment of a fluid conduit is commutated to contact either the heated or the cooled thermal mass to thaw and therefore open the valve or cool and thus close the valve. The operation of the Peltier heat pump at a constant temperature avoids problems inherent in the use of a Peltier heat pump to both heat and cool a freeze thaw segment.

Abstract: A method and apparatus for controlling fraction collection in an eluent stream flowing from an LC column. A triggering detector recognizes the presence of a target substance according to characteristics of chromatographic peaks in the eluent stream and initiates a delay timer to trigger the fraction collector. A waste stream detector is disposed at any distance from the fraction collector to detect peaks in the waste stream flowing from a fraction collector. The signature of fraction collector actuation is seen by the waste stream detector, permitting the delay time to be adjusted for optimal collection of the target compound. The presence or absence of a peak or the characteristics of a remnant peak detected by the waste stream detector are used to confirm that the target component of the eluent stream was collected as intended by the fraction collector.

Abstract: A method of analyzing machine vision images to identify low contrast features such as scratches or cracks on the polished ends of optical fibers. A bank of oriented filters having incremental angles of orientation are tuned to respond to the frequency characteristics of oriented scratches or cracks having an approximate width. The filters are applied to an image to generate a filter response image for each filter orientation. The set of filter response images are combined to form a single data set indicating a magnitude and angle for each pixel in the original image. Elements of the combined data set having corresponding angles and magnitudes are grouped to form contour components that can be optionally input to higher order processes.

Abstract: A method is provided for robustly and efficiently identifying contours in an image of an object. Features are extracted from an image, typically using a Sobel edge detector or a set of large oriented filters, and are locally chained to form contour segments of particular character, such as line segments. A spatial hash table is used to access the contour segments according to the location of their endpoints. Candidate sets for joining to grow contours are reduced by considering only segments having ends in adjacent spatial hash bins. Contour constraints are applied to appropriately choose among the candidates to form contours. The method facilitates robust and efficient scratch detection of fiber-optic end faces, or of any surface that may have smoothly curved scratches.

Abstract: A two-dimensional (2-D) machine-vision safety method and apparatus performs high-integrity, high efficiency machine vision. The system digitally filters a configurable number of time-sequenced camera images of a viewed area to create a filtered image. Objects within view in a training phase are detected and compared to objects detected in a runtime phase. Each new image is then compared to the previously created model and a pixel-oriented difference image is calculated. The difference image is then processed for segmentation features attributable to an intruder object. Alarm conditions are determined from threshold parameters related to location of the intruder objects. For segmentation results that exceed a predetermined threshold, an alarm condition is set. Setup parameters are automatically generated by analysis of distinctively marked physical boundaries in an image.

Abstract: A method of detecting a road lane in an electronically stored image. An image acquisition device acquires an image of a road lane environment and stores the image as an array of pixels. An edge detector generates a list of feature edges form the image. Lane marker edge pairs are filtered from the list of features according to a set of criteria. Lane marker edge pairs are sorted into lists corresponding to individual lane markers. Individual lane markers defining a left and right boundary of a road lane are geometrically identified. Three dimensional curves are fit along centers of mass of the sets of left and right lane markers to model a road lane boundary.

Abstract: The invention features an optical medium for calibrating UV absorbance detectors, methods for making such an optical medium, and methods for calibrating UV absorbance detectors using such a medium. The optical calibration medium includes a gel-sol silica glass monolith with a rare-earth dopant therein. The rare-earth dopant exhibits at least one spectral feature in at least the far UV range. The constituents of the gel-sol silica glass monolith are selected so the rare-earth doped sol-gel glass monolith exhibits a transmittance in the far UV range so each distinct spectral feature of the rare-earth dopant in the far UV range is discernable. The transmittance in a particular embodiment is at least about 50% at about 250 nm. The rare earth materials selected for use as dopants are those exhibiting a wide range of spectral features, preferably over a range from about 190 nm to about 700 nm and more particularly exhibit at least one distinct spectral feature in the range from about 190 nm to about 300 nm.

Abstract: Gradient performance with high pressure gradient solvent delivery system is optimized by approximation of infinite stroke volume of high pressure pumps by the addition of pulse dampening with backflow prevention to each high pressure pump. The backflow prevention adds sufficient minimum flow resistance, thereby enhancing the performance of the pulse dampening over a wider range of flow rates resulting in consistent gradient performance.

Abstract: A capillary column comprising monodispersed particles. The capillary is formed using a suitable substrate, wherein two plates are bonded together. At least one of the plates comprises a channel where particle beads are housed. Particle bead positions are of defined and equivalent diameter are arranged along the longitudinal axis of the housing structure. These positions are used to position packing material used to occupy the column. The particle beads themselves are of equivalent diameter.

Abstract: A photometric measurement flow cell having measurement path-lengths that can be adjusted down to less than 0.1 mm. The measurement path-length is controlled by both a common flow cell body and the dimensional parameters of a stepped sealing optical element. The stepped optical element includes a stem portion that can be made in various lengths to create a family flow cell measurement path-lengths. The replacement of one stepped element with another having a different stem length within the flow cell creates a reliable method to adjust the measured path-length of the flow cell.

Abstract: A method and apparatus implementing dynamic thresholding techniques in processes that use image subtraction. The subtracted image is separated into a positive difference image using a positive image map and a negative difference image using a negative image map. A positive threshold map and a negative threshold map process a Gaussian filtered first image to generate respective positive and negative dynamic threshold images. The positive and negative threshold map mask out irrelevant areas and implement adaptive gain in pixel thresholds proportional to a difference or contrast between foreground or feature of interest and local background. Dynamic thresholding is a subtraction providing a subtracted positive image and a subtracted negative image. The subtracted positive and subtracted negative images are combined to provide a merged image which is binarized. Edge or Interface detection involves edge detection and true peak detection to find the edge peaks in a pre-image and post image.

Abstract: A hydraulic amplifier system for an ultra-high pressure liquid chromatography system. The hydraulic amplifier system includes a hydraulic cylinder comprising a primary piston chamber in which a primary piston is disposed and a secondary piston chamber in which a secondary piston is disposed. The cross-sectional area of the primary piston is larger than the cross-sectional area of the secondary piston. The difference in the cross-sectional areas of the pistons creates an amplification of the pressure in the primary piston chamber and a reduction in flow rate.

Abstract: An improved method and apparatus for identifying peaks and for determining the boundaries of those peaks, and boundaries of multiple peaks and shoulders within chromatograms. The method and apparatus effects real time identification and determination of the boundaries of these peaks for the purpose of fraction collection. The method and apparatus determines the boundary of a peak within a detector response profile that comprises data points plotted graphically on an X and Y-axis wherein the X-axis represents a first variable and the Y-axis represents a second variable, each variable having a value. The plot at each of the data points has a slope. Data points having a slope which deviates from a consistent value define a peak, and data points having a slope with a consistent value define a baseline.

Abstract: A three-dimensional (3-D) machine-vision obstacle detection solution involving a method and apparatus for performing high-integrity, high efficiency machine vision. The machine vision obstacle detection solution converts two-dimensional video pixel data into 3-D point data that is used for calculation of the closest distance from the vehicle to points on the 3-D objects, for any object within view of at least one imaging device configured to provide obstacle detection. The obstacle detection apparatus includes an image acquisition device arranged to view a monitored scene stereoscopically and pass the resulting multiple video output signals to a computer for further processing. The multiple video output signals are connected to the input of a video processor adapted to accept the video signals. Video images from each camera are then synchronously sampled, captured, and stored in a memory associated with a general purpose processor.

Abstract: A LC column cartridge comprising a memory component integrally attached to it at the time of its manufacture, as well as a method for producing such a LC column cartridge with an integral memory component is disclosed. The memory component is a semiconductor memory chip. The amount of data stored will depend upon the memory capacity of the component, and how the data is recovered will depend on whether or not a microcontroller is incorporated in the component itself. Components could be read only or read/write or be partitioned with a read only area for manufacturing information and a read/write area for usage data. The information stored could vary from the minimal amount of data required to identify the column and its quality control test performance in text format to a full quality control trace and usage history.

Abstract: High pressure capillary liquid chromatography solvent delivery is effected at substantially low volume and atmospheric pressure. The low volume solvent composition is subsequently pressurized and expelled at high pressure into a receiving device such as a column. The solvent composition is expelled from a fluid metering system configured to deliver liquids at low pressures to a storage matrix via an isolation valve. The solvent composition is delivered to the storage matrix in reverse order such that the first volume of liquid delivered into the storage matrix is the last volume of liquid expelled out. Liquid pre-existing within the storage matrix is transferred into a fluid accumulator in fluid communication with the storage matrix. The fluid accumulator is enveloped in a pressure caisson which can be pressurized or depressurized in response to sensor signals obtained from a fluid volume displacement transducer and a pressure sensor, in accordance with solvent composition cycle formation.

Abstract: A method of inspecting semiconductor die and lead frame assemblies uses rotation invariant/scale invariant processing methods of machine vision data. A training image is acquired and processed to form a training model. A runtime image is acquired and processed using rotation invariant/scale invariant tools to find a runtime instance of the trained model and produce x, y, theta and scale information. The runtime instance is aligned to the train time model, or vice versa, and then compared to the train time model. The features and edges from the runtime image are compared to features and edges of the training model to identify discrepancies as possible defects. The possible defects are further processed with a morphological filter and/or a blob filter to further refine images of the defects. Alternative implementations of the invention measure adhesive wet-out around semiconductor dies and provide measurements of die rotation.