Abstract: Improved calibration of optical wavelength measuring instruments. In a first embodiment, improved calibration is achieved in an optical wavelength measuring instrument by performing calibration measurements at a plurality of known wavelengths and using an average calibration constant derived from the plurality of measurements. In a second embodiment, improved calibration is achieved by performing calibration measurements at a plurality of known wavelengths and calculating a linear or higher order calibration model, or a periodic model. These approaches may be extended by segmenting the wavelength range and using different calculated calibration values, or different calibration models, for each segment.

Abstract: A light emitting diode (LED) driver pad comprising a multiplying digital to analog converter (MDAC), which allows for differing LED characteristics to be matched digitally. Either a plurality of MDACs are integrated onto a single integrated circuit, one MDAC per color of LED, or a single MDAC may be multiplexed to drive a plurality of different color LEDs. The MDAC allows for LED operating current to be set digitally, while allowing an overall brightness or intensity control, thus achieving uniform color balance over a range of operating characteristics.

Abstract: Wavelength reference standard using multiple gasses and calibration methods using same. A wavelength reference using absorption lines of multiple gasses provides stable reference wavelengths over multiple regions of interest of the optical spectrum. The gasses may be in separate cells or combined in one cell. Improved calibration using the reference is achieved by performing calibration measurements at a plurality of known wavelengths and using an average calibration constant derived from the plurality of measurements. In a second embodiment, improved calibration is achieved by performing calibration measurements at a plurality of known wavelengths and calculating a higher order calibration model, such as a least-squares linear fit. Both approached may be extended by segmenting the wavelength range and using calculated calibration values for each segment.

Abstract: Method for identifying low charge, low weight ions with multiple charge states in mass spectrographic analysis. Ions are matched to a charge series by testing peak width, isotope spacing, and isotope ratios, using instrument resolution and information derived from the instrument spectrum. By following these tests erroneous assignment of ions to a series are avoided, providing higher quality data to the user.

Abstract: Graphics tablet scanning and error reduction. Errors are detected and reduced by reading a plurality of points, sorting the points, and selecting the median point. Errors are detected and reduced by comparing the range of lowest to highest points with a preset limit and signaling an error if the limit is exceeded. Errors are detected and reduced in a resistive tablet by placing a load resistance on the output of the tablet and comparing the output voltage with predetermined limits, characterizing the contact area into valid and invalid contacts.

Abstract: Method and apparatus for accurately determining the charge state of a battery is disclosed. The charge state is derived from the battery voltage, which is corrected for errors introduced by temperature and series resistance. Error from series resistance is minimized by either making an open circuit voltage measurement, or by making a plurality of voltage measurements under known load conditions, calculating the series resistance from these measurements, and calculating an equivalent open circuit voltage, compensating for the voltage drop caused by the series resistance of the battery. Errors introduced by temperature induced shifts in battery voltage are corrected by reading the battery temperature and correcting the battery voltage to a reference temperature. The battery voltage corrected for temperature and series resistance effects is used to compute charge state by table look up or algebraically.

Abstract: A mechanically latching button for a cursor control device such as a mouse or trackball is disclosed. The latching mechanism improves performance during dragging operations, while not affecting the button's rapid response needed for ordinary clicking. A first embodiment uses a stepped button. In a second embodiment, a sliding latch button is used. In a third embodiment, a push latch button is used. In a fourth embodiment, a snap action latch with a latch release button is used.

Abstract: A stochastic priority based scheduler for selecting executable tasks in a computer system is disclosed. The stochastic priority based scheduler selects tasks on the basis of a random number weighted by task priority. Since every task has a nonzero finite probability of being selected, the probability being proportional to the task priority, all tasks, even low priority ones, have a chance of being selected, thus eliminating the lockout problem.

Abstract: An improved degauss coil for use with cathode ray display tubes is disclosed. The degauss coil is formed from conductive traces placed directly on to a plastic part attached to or adjacent the front bezel surrounding the cathode ray tube. Alternatively, the conductive traces may be placed directly on to the bezel itself. The invention allows for a very narrow bezel border surrounding the cathode ray tube.

Abstract: A process for creating a work of art from a base medium, crayon and ink that comprises selecting a base medium that affords a surface to which crayon and ink can adhere, applying a crayon to the surface of said base medium, removing from the surface of said base medium any excess crumbs of crayon that failed to firmly adhere to the surface of said base medium, applying ink over the surface of the areas of crayon and the surface of the areas of the base medium that are free of crayon, removing substantially all the ink other than a thin film of ink from the surface of the areas of crayon and the surface of the areas of the base medium that are free of crayon before the ink is allowed to dry, allowing the thin film of ink to dry on the surface of the areas of crayon and the surface of the areas of base medium that are free of crayon, and rubbing the surface of the areas of crayon and the surface of the areas of the base medium that are free of crayon to remove a portion of the dried ink and produce a sheen to t

Abstract: A game timing apparatus and method for simultaneously timing events for two players is disclosed. The method involves presetting a pair of clocks for respective initial time periods, starting one of the clocks to time a first player's move, simultaneously stopping one clock and starting the other, and incrementing or decrementing each of the clocks by a time interval once for each move or a group of moves. The apparatus includes a pair of clock means, a pair of start switches for starting and stopping the clock means, and a compensation means for incrementing or decrementing each clock means by a time interval.

Abstract: A rail connector for use in connecting pipe rails to pipe posts includes a circular tubular member with a reduced sleeve which fits inside a pipe rail and substantially conforms to the inner surface of the pipe rail to provide a tight fit between the connector and pipe rail. The connector includes a mechanism for adjusting the diameter of the sleeve to provide a tight fit between the sleeve and the rail. This mechanism includes a wedge member having substantially rounded sides such that minor deviations in the machining of the sleeve can be accommodated. Also disclosed is a mechanism for locking the pipe rail on the connector so that the pipe cannot be removed.

Abstract: An apparatus usable in process control applications for detecting the position of a movable element in a sensor wherein first and second beams of light, each having different wavelengths and each preferably being alternately generated with respect to one another by a light source, are transmitted to a filter by means of an optical fiber cable connected between the light source and filter. The filter and the movable element cooperate for modulating the intensity of the first beam in accordance with the position of the movable element and thereby transforming that first beam into a measurement beam which appears at an output stage of the filter. The filter also transmits the second beam therethrough unaffected by the movable element and produces a reference beam appearing at the output stage. A first optical detector coupled to the light source the respective intensities of the two light beams being transmitted towards the filter.

Abstract: An element interacting with a stream of a fluid moving through a pipe generates periodic sub-flows at a rate that varies in accordance with changes in the velocity of the moving fluid. The generation of sub-flows also modulates the electrical charges contained in and moving with the fluid thus permitting a detector which is responsive to the energy being radiated by the modulated charges to produce a sensor signal having a frequency corresponding to the generating rate of the periodically produced sub-flows. In one preferred embodiment, the element is a vortex-shedding body and the sub-flows are vortices being shed therefrom. Electrical circuitry which receives the sensor signal converts it into a flow signal representative of the velocity of the moving fluid.

Abstract: A vortex-shedding mass flowmeter which includes a shedding body mounted in a pipe containing a flowing fluid, a first detecting element that responds to the vortices generated when the fluid flows past a surface of the shedding body for producing a velocity signal proportional to the flow rate of the fluid, a second detecting element for sensing in a measuring plane that includes the surface of the shedding body where vortices are generated a moving fluid characteristic dependent on the product of fluid density and the square of the fluid flow rate, and electronic circuitry coupled to the outputs of the first and second detecting elements for producing therefrom a mass flow rate signal. In one preferred embodiment, the second detecting element is a pitot-type head device which senses a pressure differential between static and dynamic pressures existing at two locations on the measuring plane.

Abstract: A small line-size vortex meter comprising a small-diameter flow tube cast with an integral vortex-shedding bar and an external sensor housing. The outer surface of the housing is formed with an approximately circular recess extending towards the flow tube and communicating with the interior of the tube through side-by-side impulse ports located adjacent one end of the vortex-shedding bar. Inserted into the central region of the recess is a sensor body having diaphragms on opposite sides to respond to vortex pressure fluctuations transmitted through the impulse ports to chambers along the sides of the sensor body. The sensor body comprises an oil-filled capsule with the diaphragms serving to transmit the pressure fluctuations to a piezo-electric sensor element which produces corresponding electrical signals.