Abstract: A field sequential color display system (10) employs a liquid crystal device operating as a variable optical retarder (12) which is positioned in front of the screen (40) of a raster scanned cathode ray tube (38) to develop a high quality multicolored image. The liquid crystal device is divided into upper and lower cell segments (34 and 36) to decrease the time between successive color fields. Each cell segment has a separate electrode structure (30 and 32) and a common electrode structure (22) and is separately commanded by a switching circuit (46) to a predetermined optical retardation state when the electron beam scans the portion of the screen covered by the cell segment. The switching circuit provides signals in a predetermined time sequence to the cell segments to minimize the optical cross talk between them and thereby minimize the spurious transmission of colored light from the display system.

Abstract: A polyimide embedded conductor process assures adherence of a metal conductor to a polyimide layer and allows closer spacing between conductors. The conductor is laid on a sacrificial substrate, and then the polyimide layer is laid over the conductor and substrate. The substrate is etched away to expose the conductor, and the polyimide layer may be etched away from the conductor to form attachment tabs.

Abstract: An optical switching device selectively couples an optical port of a first type (e.g., an input port, at which a light beam is introduced into the apparatus) to one of at least two optical ports of a second type (e.g. output ports, from which a light beam leaves the apparatus) which are at predetermined, angularly-spaced positions about a central axis of the device. The device comprises an optical imaging device mounted to rotate about the central axis between a first position, in which the port of the first type is optically conjugate with one of the ports of the second type, and a second position, in which the port of the first type is optically conjugate with the other port of the second type.

Abstract: An integrated circuit package comprises an integrated circuit chip and a flexible sheet-form interconnect member that comprises dielectric material and conductor runs supported by the dielectric material in mutually-insulated relationship and having termination points arranged at the main face of the interconnect member in a pattern that corresponds with the pattern of contact pads on the interconnect face of the chip. The chip and the interconnect member are adhesively bonded together by means of a material that is interposed between the main face of the interconnect member and the interconnect face of the chip, but is not interposed between the contact pads and the termination points, and adheres to both the interconnect member and the chip.

Abstract: Apparatus for defining a bank of sequential windows from a raster-scanned image of a document for storage in a data base. In addition, the apparatus includes a look-up table for each window wherein the bit pattern of the window is used to determine the correction factor which is applied to the next window as the "new" bit from a set of patterns and correction factors derived from well known algorithms developed to minimize the amount of data needed to electronically recreate a given document. The apparatus also includes storage devices to permit the application of the algorithm in overlapping pieces over the face of the document.

Abstract: A delayed sweep oscilloscope having a word recognizer displays multi-digit parameters representing an event count necessary to initiate a delayed sweep, and a word to be recognized on oscilloscope data input lines. The numbers are modified digit-by-digit by rotating a first control knob to move a cursor on the screen to select a digit to be altered and then by rotating a second control knob to alter the selected digit. The control knobs are mounted on the oscilloscope front panel and when not used to modify these parameters, the control knobs may be used to control other oscilloscope functions.

Abstract: A trigger holdoff system particularly useful in digital oscilloscopes is provided in which a holdoff pulse is generated in response to a trigger pulse from a trigger generator and applied to the trigger generator to disable a time base control circuit.

Abstract: A digital oscilloscope provides sine interpolation between sampled data points and includes means for intensifying the cathode-ray-tube display to emphasize portions of the cathode-ray-tube trace corresponding to original samples while deemphasizing portions of the trace representing interpolated information.

Abstract: In accordance with the present invention, a drum (10) has a central shaft (11) which is rotatably mounted to a drum supporting frame (12). A mount (26) pivotally connects one side (30) of the frame (12) to a cabinet (14) for pivoting about a frame pivot (73). A mount (15) rigidly secures the other frame side (32) to the base (14). An isolation mounting bracket (86) supports an optical encoder (84) in position to monitor the velocity of the shaft (11). Bracket (86) has pivots (98, 100) which cooperate with the frame pivot (73) to provide in effect a parallelogram support structure for the optical encoder (84). Thus, the encoder (84) may translate, but not rotate, in response to vibrations of the frame (12) so as to minimize or eliminate erroneous encoder velocity readings otherwise arising from such vibrations.

Abstract: A microprocessor stepper motor drive uses a single acceleration/deceleration profile regardless of the final velocity of the device being driven. A first down counter stores the desired final velocity from a microprocessor. An acceleration/deceleration profile is stored in a storage device and added to the desired final velocity to produce a smooth velocity profile.

Abstract: A visual indication of the relationship between first and second electrical signals, such as the left and right channel signals in a stereophonic audio system, is provided through use of a video vectorscope. The first and second signals are used to modulate the amplitude of two sinusoidal waves at a subcarrier frequency and in phase quadrature, so as to synthesize the chrominance portion of a composite video signal. The two modulated sine waves are additively combined, and the resulting signal is applied to the input terminal of the vectorscope.

Abstract: A coupling discriminator for Ethernet standard local area network interface equipment monitors the electrical characteristics of an incoming differential signal pair, discriminates between a signal pair that is direct coupled and a pair that is transformer coupled, and configures the interface equipment for operation with the type of coupling detected.

Abstract: A charge coupled device (CCD) analog shift register in a two-channel serial-parallel-serial (SPS) structure operating in a fast-in/slow-out (FISO) mode for high speed signal acquisition and temporary storage of a plurality of samples. The two CCD arrays are clocked simultaneously, and the input analog signal is demultiplexed to the two arrays. Additional transfer electrodes are provided at the input of one of the arrays, and the other array is provided with a sampling clock which is 180.degree. out of phase with the sampling clock of the first array; two consecutive samples of the input signal are taken during each transfer clock cycle. All signal samples are clocked through the arrays simultaneously and appear at the output at the same time.

Abstract: A rotary control having a variable detent is disclosed. The control, for electrical instruments and the like, includes a manually rotatable shaft to which a plate is coaxially mounted. The plate includes magnetizable flutes extending radially therefrom, each flute corresponding to a rotational stop position of the rotary control. Spaced adjacent the plate is a switchable electromagnet that forms a detent. A control switch in communication with the electromagnet selectably energizes it to engage magnetically the flutes successively as the shaft is manually rotated, stopping the rotary control at each rotational stop position. The switch also de-energizes the electromagnet so that the shaft may be continuously variable. A plurality of electromagnets can be positioned about a plate to vary the locations of the rotational stop positions. In a separate embodiment, a plurality of plates, each with an associated electromagnet, is mounted coaxially on the shaft.

Abstract: A travelling wave sampler has an input terminal for receiving an input signal to be sampled. A first diode has its anode connected to the input terminal, whereas a second diode has its cathode connected to the input terminal. A first delay line is connected between the cathode of the first diode and the anode of a third diode, and a second delay line is connected between the anode of the second diode and the cathode of a fourth diode. A strobe generator provides negative-going strobe pulses to the cathode of the third diode through a first strobe capacitor and provides positive-going strobe pulses to the anode of the fourth diode through a second strobe capacitor. The third and fourth diodes are maintained in zero biased condition when strobe pulses are not provided by the strobe generator and are forward biased during the strobe pulses.

Abstract: A junction field effect transistor circuit is used to detect the power level contained in radio frequency signals over a wide range of frequencies and signal levels. The radio frequency signal is coupled to the drain of a junction field effect transistor, the gate of which is biased at a d.c. potential equal to the pinch off voltage. The radio frequency signal is also coupled to the gate. The resulting current from the source contains a d.c. term proportional to the square of the magnitude of the radio frequency signal, as well as time varying signal components. A low pass filter is employed to remove the time varying signal components from the resulting source current to produce a D.C. output current which is proportional to the power level of the input signal.

Abstract: A potentiometer which provides the function of an on/off switch includes a center conductor connected to a conductive ring and a resistive element concentrically disposed about the conductive ring. The resistive element includes a pair of termination pads and one of the pads includes a branch which is situated outside the outer periphery of the resistive element. As a wiper arm traverses the resistive element it remains in contact with the branch for a brief distance and then loses contact with it. This causes the value of the resistance in the potentiometer to make an abrupt shift in magnitude which can be used to initiate various switching functions.

Abstract: An oscillator produces an output signal which is frequency locked to a reference signal but phased locked to a triggering signal. The oscillator includes a NOR gate having its output fed back to one of its inputs through a programmable delay circuit while the triggering signal is applied to another of its inputs. When enabled by the triggering signal, the output signal of the NOR gate oscillates at a frequency inversely proportional to the delay time of the delay circuit. The delay time is controlled by a control circuit which counts NOR gate output signal cycles occurring during a predetermined number of reference signal cycles and increments the delay time when the count is higher than expected for an oscillator output signal of a desired frequency and decrements the delay time when the count is lower than expected.

Abstract: A method and apparatus for removing undesirable dots and voids which are smaller than the user defined smallest data item of a bit-map image of a picture being scanned by a picture coding system. The bit-map is delayed as it is being generated to form a series of tessellations or windows of data of selected sizes. The windows are propagated through a series of neighborhood-logic elements which with the output data level of the outer ring of neighborhood-logic elements which define the window being examined to determine if those data levels are all of the same sense. If they are all of the same sense, then all of the neighborhood-logic elements which define the interior of the window are set or cleared so that the output data levels of all of the neighborhood-logic elements which define the window are of the same sense.

Abstract: A detector circuit for detecting skew or phase shift of at least three logic signals comprises an OR gate for receiving a plurality of logic signals, an exclusive-OR gate for receiving an output signal from the OR gate as well as a reference logic signal, and a pulse width check circuit responsive to the exclusive-OR gate for providing the skew detection result.