Abstract: A circuit for unambiguously indicating the presence and comparative values of output signals from a plurality of sensors includes first and second comparators respectively providing first and second comparison signals having high or low logic levels. A source of reference voltages provides individual reference voltages to one input terminal of each of the comparators. A first sensor is arranged between a source of operating potential and a second input terminal of the first comparator. The first sensor switches the operating potential on and off of the second input terminal in accordance with the reception of energy by the first sensor to vary the output terminal of the first comparator between high and low logic levels when the reference potential exceeds the operating potential. A second sensor arranged is between the source of operating potential and the second input terminal of the second comparator.

Abstract: A system for reducing crosstalk in an optical scanning device for recording and reading optical data and magneto-optical data arranged in tracks of a recording medium includes a source for providing two light beams which are scanned along the tracks. The light beams are polarized in two polarization directions, are focused onto one of the tracks and are separated by a predetermined distance along the direction of the tracks, when incident on the tracks. Reflected light from the recording medium is focused onto first and second pairs of sensors. The difference of the signals from the first pair of sensors is compared with a delayed version of the difference of the signals from the second pair of sensors to provide a further signal representing magneto-optically recorded data. Signals from a first sensor of each pair of sensors may be summed to detect optically recorded data.

Abstract: A first input signal has successive zero amplitude crossings. A first comparator generates a first bilevel output signal responsive to the first input signal. The first comparator has a hysteresis characteristic which is switched on at each said zero crossing of the first input signal and switched off prior to each occurrence of the next following zero crossing. A second input signal has successive zero amplitude crossings and is displaced in phase relative to the first input signal. A second comparator generates a second bilevel output signal responsive to the second input signal. The hysteresis characteristic is switched on by level transitions of the first bilevel output signal and switched off by level transitions of the second bilevel output signal. The first and second input signals may be sinusoidal. The hysteresis characteristic may controlled by first and second flip/flops, which are set by the first bilevel output signal and reset by the second bilevel output signal.

Abstract: A method of recording bursts of digital data onto a rotating recording medium having a helical data track moving at a fixed linear rate with respect to a read/write unit includes the steps of temporarily storing the data bursts and reducing the data rate of the bursts during storage. The bursts are stored as clusters at spaced locations around the track while leaving pauses between the clusters. The pauses are used to relocate the read/write head to the position where the next burst will be recorded before recording the next burst.

Abstract: Direction determining logic for a regulation circuit which guides a detection device along the data tracks of a recording medium receives an HF signal indicating when the detection device scans a dirty or damaged area of the recording medium, and a tracking error signal when the detection device leaves the track. The direction determining logic includes first and second multiple input terminal logic gates for respectively providing first and second complimentary output signals. A bistate logic circuit is selectively responsive to the HF signal and the tracking error signal and provides complementary output signals to one input terminal of each of the multiple input terminal logic gates. Other logic selectively inhibits the other input terminal of one of the multiple input terminal logic gates as the detection device scans a dirty or damaged area of the recording medium and the other of the multiple input terminal logic gates when the tracking device leaves the track.

Abstract: A system for controlling the number of data tracks crossed by the tracking head of a recording/playback device as the tracking head moves in a desired direction over a recording medium includes a counter having n output terminals. The counter is initially set to a count representative of the desired number of data tracks to be crossed as the tracking head moves in the desired direction. An further counter, also having n output terminals individually corresponding to the output terminals of the counter, is set to a predetermined count. Counting pulses are provided to the counter when the tracking head moves in the desired direction and to the further counter when the tracking head moves in a direction opposite from the desired direction. The output terminals are compared and a stop signal is generated when all terminals of both counters show that both counters are in the same state.

Abstract: In a method of compensating for the tolerance errors in a digital-to-analog converter (D/A) the tolerance errors of the D/A are measured and individual correction factors are provided for each of the errors. The correction factors are stored and one of them is arithmetically combined with a portion of the digital number being converted to produce a combined signal. The combined signal is input into the digital-to-analog converter to produce an analog signal accurately representative of the digital signal.

Abstract: An automatic gain control circuit includes an amplifier, the gain of which is to be controlled, and an input terminal for receiving an analog input signal. A first signal path is arranged between the input terminal and the amplifier and includes a controllable switch and a first filter. A second signal path is responsive to the input terminal and includes an analog-to-digital converter for providing digital signals representative of levels of the analog input signal. A signal processor receives the digital signals and provides control signals. A pulse width modulator receives the control signals and provides a pulse width modulated signal, the width of which varies in accordance with the digital signals, to the controllable switch.

Abstract: A variable width pulse generator includes a plurality of logic stages which are coupled cascade. Each stage is arranged to select one of a plurality of clock signals of differing phase applied thereto responsive to particular bits of a data word defining the pulse width. All of the stages are initially disabled by a precharge pulse occurring at the beginning of each variable pulse interval. The successive stages are enabled by the occurrence of a clock pulse of a clock signal selected by the previous stage. The lastmost stage provides an output corresponding to the width pulse.

Abstract: A variable width pulse generator includes a plurality of logic stages which are coupled in cascade. Each stage is arranged to select one of a plurality of clock signals of differing phase applied thereto responsive to particular bits of a data word defining the pulse width. All of the stages are initially disabled by a precharge pulse occurring at the beginning of each variable pulse interval. The successive stages are enabled by the occurrence of a clock pulse of a clock signal selected by the previous stage. The lastmost stage provides an output corresponding to the variable width pulse.

Abstract: A transistor has a superlattice in the channel region. The superlattice has alternate interleaved layers of undoped wide and narrow bandgap materials with the layers extending in a direction parallel to the channel region. Preferably a narrow band gap layer is adjacent a gate insulator to provide maximum increase in mobility.

Abstract: A system for inputting a multi-bit input to a computer in response to the closing of a single switch includes a multi-line to a single line encoder. A plurality of input switches individually set different input position numbers into the encoder. When the input from a binary counter equals the number, the number is output to the computer.

Abstract: A support for establishing the sealing length of kinescopes includes a pivotable support. The support is contoured to conform with a contoured neck area of the kinescope whereby the contour references the envelope to a seal plane.

Abstract: A system for sequentially refreshing segments of the stored voltage characteristics of electron guns includes a clock gate. The clock gate passes clock pulses to a counter which refreshes the stored voltage signals. After a predetermined number of counts, the counter inhibits the clock gate until a vertical blank pulse enables the clock gate and the counter resumes counting.

Abstract: A welding apparatus for welding a washer to a frame retaining spring while the washer and the spring are in engagement with a stud affixed to the sidewall of a kinescope panel. A welding head is suspended by an articulated joint and by flexible straps whereby the welding head is free to pivot and to flex to assure engagement with the parts to be welded when the spring is out of alignment with the welding head.

Abstract: A system for converting the frequency of a pulse train to a binary number includes an output counter which converts the pulse train to the binary number. Sampling time periods are applied as pulses to a comparator through another counter. The number of desired sampling periods is set into the comparator. The comparator enables the counter during the sampling time periods and inhibits the output counter on the termination of the total sampling time periods. The output of the output counter, therefore, is a binary representation of the frequency of the incoming pulse train during the total sampling time period.

Abstract: Electron emissive material is applied to a line cathode by surrounding the cathode with cylinders at the locations where deposition of the material is desired and voltage biasing the cylinders positive with respect to the line filament for a prescribed time.

Abstract: An electron beam guide assembly for a flat panel display device includes an acceleration electrode having two portions separated by a longitudinal slit. The display device also includes electrodes on support walls which divide the device into channels. By properly voltage biasing the acceleration electrode portions and the support wall electrodes, an electron beam is simultaneously directed to a particular color producing material and transversely scanned across the channels. A color display, therefore, can be produced using one electron beam per channel.

Abstract: A system for measuring figures projected onto a charge coupled device (CCD) sums the data from a preselected number of adjacent pixels in a particular pixel line. The sum signal is divided by a full pixel signal to provide a mean pixel signal. The mean pixel signal is multiplied by a dimension per pixel value to provide a dimension signal representative of the dimension being measured. The dimension signal is compared with a reference dimension to determine the acceptability of the figure being measured.

Abstract: An evacuated envelope having a plurality of spaced, parallel support walls extending between and substantially perpendicular to flat substantially parallel front and back walls to provide a plurality of parallel channels extending along the front and back walls. The front and back walls and the support walls are of an electrically insulating material, typically glass. Compressed between each of the support walls and the front wall is a metal strip which serves as the tip of the support wall and which extends along the entire length of the support wall. Each tip is tapered in thickness from a thickness substantially equal to the thickness of the support wall at the support wall to a thinner thickness at the front wall. Means is provided between each metal tip and either the support wall or the front wall to prevent movement of the tip transversely of the channels. A shadow mask extends across each of the channels and extends between the metal tips and the support walls.