Abstract: A process for manufacturing an insulated gate field effect semiconductor device having self-aligned contact regions. The process avoids the need for a masking step for the application of interconnecting contacts by providing a dielectric material having a low melting point over the gate region of the semiconductor. The dielectric material is heated to its melting point such that it covers and encapsulates the gate. Contact material is then subsequently provided using the self-alignment feature of the melted dielectric which isolates the gate from the contacts.

Abstract: A solid state microwave power source for providing microwave power to excite an electrodeless lamp is designed so as to provide an acceptable impedance matching characteristic during lamp warm-up when the lamp impedance is high and changing with temperature to provide sufficient power to the lamp during the running state when the lamp impedance is matched to the source. The microwave power source includes a dc power source providing power at variable levels, a microwave oscillator receiving the dc power to produce a microwave signal, and a microwave power amplifier. The oscillator has a transistor in a common base configuration, a microstrip capacitive feedback element to sustain oscillations, and an output impedance matching arrangement formed from microstrip. The microwave signal is amplified in the solid state power amplifier having a power transistor in a common base configuration.

Abstract: A tubular shaped aperture extends through a mounting base and includes two aligned sections of different sizes so that the junction of the two sections provides an abutment. A mirror is positioned within the larger section with the reflective side facing the smaller section and abuts against a ring-shaped spring device therebetween. A plurality of adjustable screws engage the reverse side of the mirror to control the orientation of the mirror relative to the axis of the aperture and to adjust the position of the mirror along the axis.

Abstract: Improved efficacy is obtained in an electrodeless light source of the type having a high frequency electrodeless lamp disposed at the ends of inner and outer conductors of a termination fixture by evacuating the region between the lamp envelope and the outer conductor to reduce conductive and convective heat losses.

Abstract: A half wavelength resonant cavity having inner and outer coaxial conductors is coupled at one end to a dc power source, and a gas discharge electrodeless lamp is disposed in the region between the conductors at the other end of the cavity. Repetitive bursts of radio frequency oscillations occur within the cavity, the oscillations causing breakdown of the fill material within the lamp to produce light.

Abstract: A starting assist control circuit for an electrodeless light source in which a UV source for assisting in starting an electrodeless lamp is coupled in series with the DC supply for a microwave power source for the lamp so that a reduced DC voltage is supplied to the microwave power source at lamp starting. An electronic circuit is provided which continuously decreases the DC current through the UV source and increases the DC voltage for the microwave power source in relation to the amount of light generated by the electrodeless lamp. More specifically, the emitter and collector of a transistor are coupled across the UV source to provide a shunt path and the potential of the base of the transistor is controlled by a photosensitive resistor which senses the amount of light from the lamp. As the lamp generates increased light, the transistor becomes more conductive, thereby continuously decreasing current to the UV source and increasing voltage to the microwave power source.

Abstract: In an optical scanning apparatus for photolithographic processing of faceplates intended for color cathode ray tubes, a light beam from a source is first deflected through an angle related to a predetermined angle of incidence that an electron beam in an operating tube has with respect to a defined faceplate location, and then the deflection point is imaged onto or in the vicinity of the faceplate. This angle of incidence adjustment is accomplished for each faceplate location as the light beam is scanned over the surface of the faceplate. The light source, which is preferably a laser light source, creates a light beam having a wavelength spectrum which exposes the photosensitive material. The beam is deflected by a pair of orthogonally aligned mirrors which are rotated by galvanometers. Each galvanometer is driven by a current from an electrical control, the current being related to the proper angle of incidence for each faceplate location.

Abstract: A bonded bubble memory device includes a non-magnetic first substrate, a thin film layer of magnetic material located on a planar surface of the first substrate, the layer being adapted to sustain cylindrical wall magnetic domains, a second substrate made of a non-magnetic and non-conductive material, a desired pattern of magnetic elements and electrically conductive elements deposited on a planar surface of the second substrate, the pattern including at least three spaced points, the heights of which are equal and predetermined, the thin film layer on the first substrate being in contact with the spaced points on the second substrate so that a controlled spacing is maintained between the thin film layer and the pattern of magnetic elements. A cement composition is applied to portions of the space between the substrates to hold the substrates in a juxtaposed orientation. Advantageous methods of producing the device are also described.

Abstract: A starting assist control circuit for an electrodeless light source in which a UV source for assisting in starting an electrodeless lamp is coupled in series with the dc supply for a microwave power source for the lamp so that a reduced dc voltage is supplied to the microwave power source at lamp starting. At staring, a capacitive impedance element is coupled across the inner and outer conductors of the fixture to provide an additional starting assist by creating a condition of resonance in the fixture. A heat responsive bimetallic switch element associated with both the capacitor and the UV source automatically shorts out the UV source and decouples the capacitor after the lamp has started thereby permitting full dc power to the microwave power source during the operating condition of the lamp.

Abstract: In a gain controlled television receiver the level for detecting noise in a composite video signal is increased during the synchronization pulse intervals of the signal over that during the other intervals of the signal. This level increase is controlled by a gate which is enabled during the simultaneous occurrence of a synchronizing pulse from a sync pulse separator and a flyback pulse from a deflection circuit.

Abstract: An automatic gain control circuit provides a high gain signal representative of the difference in amplitude between the synchronizing pulses of a composite video signal and a predetermined reference level. A common emitter transistor provides high gain amplification of the composite video signal, the emitter of this transistor being biased at the reference level via a voltage reference source. The collector of this transistor is coupled to an emitter follower transistor whose output signal is filtered to produce the gain control signal. A controlled positive feedback signal from the emitter of the second transistor amplifier is coupled to the emitter of the first transistor amplifier, and by matching the feedback resistor to the collector bias resistor of the common emitter transistor, the emitter of this transistor is at a virtual ground thereby providing a high gain.

Abstract: An optical scanning apparatus for manufacturing cathode ray tubes having a faceplate with an inner surface layer of photosensitive material and an adjacent apertured mask wherein a light beam from a light source is applied to a deflection device controlled by a control circuit to effect deflection of the light beam at an angle related to the angle of incidence of an electron beam in a cathode ray tube. The deflected light beam is imaged onto the inner surface of the faceplate of the cathode ray tube through the apertured mask, and a device is provided for scanning the deflected light beam over the surface of the faceplate in a predetermined pattern to effect exposure of the photosensitive material in the proper locations for registration with the landing location of an electron beam in the cathode ray tube.

Abstract: A logic level converter converts an input signal having first and second voltage levels to an output signal having first and third voltage levels in which the voltage excursion of the output signal is greater than that of the input signal. The converter comprises first and second cross-coupled inverters in which the second inverter provides the output signal and is biased with respect to the first and third voltage levels and in which the first inverter is biased with respect to the third voltage level and the digital input signal. A voltage divider is associated with the first inverter to insure sufficient voltage swing for proper switching of the inverters. The inverters have dissimilar gains to insure that when the inverters are biased at equal voltages, the inverters always assume a predetermined state. The converter is implemented with PMOS field effect transistors and includes capacitors for increasing switching speed.

Abstract: An improved optical fiber coupler for use with eccentrically mounted optical fibers is disclosed in which a V-groove coupler block is utilized for receiving and locating the mating pair of connectors. The connectors are circularly cylindrical and each lies in an end of a V-groove recess. The V-groove at one end of the coupler block is offset relative to the V-groove at the other end by the incorporation of a thin shim on one of the faces of the V-groove. The thickness of the shim determines the amount of offset.

Abstract: The signal path between the input and output of a baseband video switch has a control point to which a signal representative of a switch control signal and a switchable constant current source are coupled. A pair of diodes and a switchable, high impedance buffer are disposed in series between the input terminal and the control point. A diode and a switchable driver are connected in series between the control point and the output terminal. A biasing arrangement responsive to the control signal biases the control point, and the current source. When the control signal is of one level, the diode junctions disposed in the path of the video signal are reverse-biased and the current source is off. When the control signal is of the other level, the diode junctions are forward-biased and the constant current source is on. A resistor load coupled between the input terminal and the control point provides a load for the signal when the switch is off.

Abstract: A transducer converts an acoustic signal into a digital pulse code signal through optical encoding techniques. A pulsed light source emits a beam of light along a predetermined path. A digital optical encoder is located in the path and emits a digitally encoded light beam having regions in which light is present and regions in which there is an absence of light. A rotatable mirror which is located in the path of the encoded beam is connected to a diaphragm so that the angle of deflection of the encoded beam is a function of the acoustic signal. An array of digitally encoded photoconductive elements is located in the path of the deflected encoded beam. Threshold circuitry monitors the variation in the resistance of the photoconductive elements and produces an N bit digital pulse code representative of the magnitude and polarity of the acoustic signal during each occurrence of a pulsed light beam.

Abstract: A television display system is described in which a full resolution, interlaced scanned display of real-time images is provided on a bistable matrix display panel. The display system has a gray scale with 64 discrete levels of brightness. The brightness levels are achieved with each panel cell turning on for one of 63 different accumulative intervals of time in response to digitized TV signals. From zero to six separate pulses of light are produced from each cell. The durations of these pulses form a geometric progression such that each of the sixty-four possible combinations of pulses has a distinct cumulative time interval. The analog TV signal is converted to a 6-bit digital word for each cell of the display panel. A memory and control system are provided for storage of the words. The least significant bit of the digitized TV signal controls the shortest pulse for the particular cell, and the most significant bit controls the longest pulse.

Abstract: A white light source is described in which a trivalent metallic ultraphosphate is irradiated with a low voltage electron beam. The metallic ions are generally restricted to the lanthanide rare earth ions and yttrium. The material so irradiated emits light in a spectral continuum centered in the visible portion of the electro-magnetic spectrum. This emission is, however, in addition to any narrow bandwidth light emission of the type generally associated with a transition of the metallic ion involving the electrons of the 4f shell.

Abstract: A tunable microwave cavity permits adjustment of the penetration of a power coupling probe into the main cavity by adjusting a grounded element of the cavity. A pair of conductive tubes are in telescoping relationship and have mutually engaging threads so that a rotation of one tube causes one tube to pass over the other. A first one of the tubes is mounted to the main cavity and around an aperture in the cavity wall. A power coupling connector is mounted with the second tube, and a rotating electrical contactor is disposed between the outer conductor of the connector and the second tube so that the connector does not rotate with the second tube. A power coupling probe affixed to the end of the inner conductor of the connector assumes various penetration depths within the main cavity in response to a rotation of the second tube. The cavity may be used in a light source including a high frequency power source and an electrodeless lamp disposed in the main cavity.

Abstract: In a light source excited with power at a high frequency, an electrodeless lamp is located in a termination fixture comprising an inner and outer conductor, the lamp being located at the end of the inner conductor. An internal tuning element is located within the fixture for creating a resonant condition when the lamp is to be started to create a maximum electric field for initiating breakdown and excitation of the fill material within the lamp. The tuner may comprise a variable capacitance coupled in parallel across the conductors at the power input end of the fixture or a variable inductance connected across the conductors at the lamp end of the fixture.