Abstract: A lithographic process utilizing soft x-rays or ions to achieve high resolution is disclosed. The process is particularly useful and semiconductor processing where high resolution is required to achieve a high density. The process utilizes a mask to selectively expose a photoresist to soft x-rays of flood beams of ions. The mask comprises a thin metallic foil supported by a frame such that the foil is in tension. The frame includes optical alignment keys. A second patterned layer of metal is affixed to the foil to form areas which are non-transparent to the soft x-rays or flood ion beams for delineating the elements of a semiconductor circuit, for example. This permits the mask to be optically aligned using conventionally techniques with high resolution being achieved due to the short wavelength of the x-ray radiation or the ion beams.

Abstract: A laser utilizing mercury halides as the lasing medium is disclosed. Electrodes selectively coated with a mercury gettering material are utilized to establish a glow discharge in the lasing medium. Proper ratio of mercury to bromine is maintained in the lasing medium to ensure long life operation.

Abstract: The invention relates to a system for sequentially analyzing each data point representing a digitized video line image and modifying the point to improve the quality of the image based upon an examination of surrounding data points. Specifically, data comprising a digitized scanned image with each point represented by a one bit digital signal is stored such that a matrix of data is continually supplied to a data multiplexer. The data multiplexer selects the portion of the matrix data to be compared to predetermined criteria to determine whether or not the data point being analyzed should be changed to improve the quality of the image.

Abstract: The invention comprises an optical interferometer system utilizing optical fibers. Titanium is diffused into the surface of lithium niobate substrate to form an optical waveguide utilized by the interferometer. The central portion of the optical waveguide is divided into two substantially parallel sections. Grooves between and alongside the optical waveguide are etched into the surface of the lithium niobate to optically decouple the waveguide sections from each other and from the substrate. A first electrode is positioned between the parallel sections of the optical waveguide with second and third electrodes positioned alongside these sections. These electrodes are utilized to subject the optical waveguides to an electrical field to differentially modulate the velocity of optical energy in the parallel sections or waveguide in response to an electrical signal.

Abstract: The invention comprises a system for deflecting an optical beam in response to an electrical signal. A collimated optical beam is generated utilizing any convenient means. The collimated light beam is injected into an optical wave guide positioned between two electrodes. One electrode is substantially coextensive with the surface of the waveguide. The second electrode comprises a series of spaced stripes parallel to the optical beam and having varying length across the surface of the electro-optically sensitive material. The electro-optically sensitive material is subjected to a varying electrical field by applying an electrical voltage to the electrodes causing the velocity of propagation of the light through the electro-optically sensitive material to vary across the layer. This changes the phase relationship of the optical beam across its diameter as it emerges from the edge of the electro-optically sensitive material. This results in a deflection of the electro-optical beam.

Abstract: The invention comprises a jam resistant radar system. The system comprises a primary radar transmitter which is coupled to a primary antenna having a predominant main beam and sidelobes. A second wide beam antenna is coupled to a second radar transmitter which transmits a signal having a frequency spectrum encompassing the main beam with the power density being substantially equal to the power density of the sidelobes of the primary antenna. The second transmitter is frequency modulated over a spectrum in discrete steps while the primary transmitter is pulse-to-pulse or look-to-look randomly modulated over the spectrum. This prevents a listening jammer positioned in the sidelobes from determining the pulse-to-pulse or look-to-look frequency being used by the primary radar transmitter.

Abstract: An automatic test system controlled by a general purpose digital central processor is disclosed. The central processor accepts test programs in a high level compiler language such as Atlas. The Atlas program is compacted into a simplified language which is utilized to communicate with test devices via a standard IEEE 488 data bus. Each of the test devices includes a programmable interface digital processor which performs any translation that may be necessary in order to permit specific test instruments coupled to the central processor via the interface processor to perform the tests specified by the high level test programs. A switching matrix also communicates with the digital processor to connect the appropriate test device to the unit under test.

Abstract: A test system utilizing a plurality of programmable test instruments each capable of executing portions of a test program with the test program being written in a compiler language such as ATLAS, for example, is disclosed. Programs specifying the tests to be performed are written in a compiler language such as ATLAS and transferred to a central control processor utilizing standard peripheral equipment. The central control processor communicates with a plurality of test instruments utilizing a series of data busses. In executing the test program, the control processor first segments the program into a series of individual tests to be performed. The test instruments are interrogated to determine which of the test instruments is currently capable of executing a specific sequence of the test program. Once an instrument has been identified which can execute the program segment, the control process transfers that segment to the instrument capable of executing the test.

Abstract: A rotary coupler for coupling a microwave signal to a rotating antenna is disclosed. The preferred embodiment comprises a section of waveguides formed into a circle and split into two pieces along the long wall of the waveguide. The two sections of waveguide are positioned to rotate with respect to each other with energy coupled into one portion of the waveguide along its narrow wall and coupled out of the second portion along its narrow wall. An isolation element is utilized at both the input and output ports to assure directional coupling into the split wall waveguide. More than one of the coupling devices can be monitored around a ship's mast, for example, to couple a plurality of microwave systems to a single multiple bandwidth rotating antenna.

Abstract: The variable impedance circuit comprising the invention provides a circuit having an impedance which varies in response to an input signal. The invention utilizes a control circuit which samples the load current and compares it to the demand signal to generate a control signal. The control signal is coupled to a load driver circuit to cause the required current to flow through this circuit. The load driver circuit and one or more substantially identical load circuits are series coupled to form a variable impedance circuit having the desired voltage and current capability.

Abstract: A method of lithographically forming a pattern on a surface is disclosed. The surface on which the pattern is to be formed is first coated with a resist layer. A mask preferably consisting of a beryllium of foil and a pattern gold layer affixed thereto is then positioned in overlying relationship to the resist layer. The thickness of the beryllium foil is selected such that it is transparent to high energy particles of a preselected energy while the combination of the pattern gold areas and the beryllium foil is impervious to these particles. A flood beam of high energy particles is directed such that it impinges on the beryllium foil thereby exposing the resist in areas not protected by the combination of the beryllium foil and the gold. The resist layer is processed to produce a patterned layer.

Abstract: A glass disc-shaped thyristor is disclosed. The thyristor comprises a body of semiconductive material having a first emitter region, a first base region, a second base region and a second emitter region therein. A cathode electrode and a gate electrode are affixed to one major surface, and an anode electrode is affixed to the second major surface of the body of semiconductor material. The cathode electrode is disc-shaped and is concentrically positioned with respect to the annular-shaped gate electrode. A ring-shaped glass member is affixed to a first major surface of the body of semiconductive material and to the edges of the cathode and base electrodes to form a seal protecting a PN junction at the interface of the first emitter and base regions. An anode electrode is affixed to the second major surface of the body of semiconductive material.

Abstract: A system for comparing the frequency of a voltage controlled oscillator to a stable reference oscillator to generate control signals which maintain the voltage controlled oscillator in phase lock with the reference oscillator. The circuit utilizes a digital frequency comparator to determine whether the output frequency of the voltage controlled oscillator is above or below the reference frequency. When the frequency of the oscillator is either above or below the desired value, pulses are generated which are integrated to produce a DC signal which changes the frequency of the oscillator to achieve the desired value. Additionally, a continuous electrical signal is generated when the output of the voltage controlled oscillator is in phase with the reference signal. When phase lock is achieved the output of the frequency determining circuit goes to zero and phase lock is maintained by the continuous electrical signal.

Abstract: A system for adjusting the sidelobe response of a main antenna is disclosed. This iterative process results permits the sidelobe canceling in sequential step reduction in interference thereby greatly reducing the time required to respond to changes in the characteristics of the interference. The response of the phased array is adjusted by combining the composite signal from the main antenna with signals from auxiliary channels which have an adjustable phase and amplitude. The desired amplitude and phase of the auxiliary channels is determined using an iterative mathematical process which emphasizes the most recent data. Emphasizing the most recent data permits the system to be used in the scanning mode or to reduce interference from moving sources.

Abstract: The invention comprises a microwave oscillator using a stripline circuit. The active device utilized in the oscillator is a bipolar transistor. A microstrip circuit is coupled to the emitter of the transistor while the collector is coupled to ground. This generates a negative impedance characteristic at the base of the transistor at the operating frequency. The operating frequency is determined by a varactor which is series tuned with an inductor. The impedance of the series tuned circuit is transformed to match the input impedance of the transistor by a microstrip circuit. Microstrip isolation circuits are utilized to couple appropriate bias signals to the emitter and the base to establish the proper operating point for the bipolar transistor. The output signal is taken from the base circuit of the transistor through the series combination of two microstrip circuits and a capacitor. A second varactor is loosely coupled to the base circuit of the transistor to provide for fine tuning.

Abstract: An interface circuit for coupling a digital processor to a core memory. The interface circuit accepts as inputs address signals, data signals, and control signals from the processor and output date from the core memory. The output of the interface circuit consists of control signals to control the memory and a parallel digital data word having 2N bits where N is the number of parallel bits transferred by the digital processor during the execution of an instruction to transfer data to or input data from an external device. To store a digital data word in a particular location in the core memory, the digital processor first transfers a digital data word having N bits to a buffer memory which is a part of the interface circuit. Next, the digital processor executes a store in memory instruction.

Abstract: A display system utilizing a non-linear raster generator is disclosed. As is conventional in raster scan displays, the scanning is controlled by two electrical signals arbitrarily designated the X and Y deflection signals. In the preferred embodiment, two memories are used to store signals which provide constants to control the amount of the non-linearity of the raster. These constants are processed to generate X and Y deflection signals which are generally hyperbolic in nature. This type of display is particularly useful for displaying mapping signals produced from airborne doppler radar.

Abstract: A system for magnifying a selected portion of a digital image as disclosed. The portion of the image to be magnified is selected and then each digital sample comprising the portion to be magnified is repeated in both the horizontal and the vertical direction to expand the selected portion of the image.

Abstract: A directional optical fiber signal tapping assembly. A light pipe rod encircles and accepts stray light rays leaving the otherwise bare outer surface of a length of optical fiber in a region following a location having a bend that induces a selected degree of outward leakage of optical signal rays in the bend following longitudinal light pipe region. Curvature of one end of the light pipe rod conducts the extracted optical signal sample to an optical detector device.

Abstract: A duplex module for simultaneous bidirectional transmit-receive communication with the end of an optical fiber or fiber bundle. The end face of an optical fiber in optical coupling registry with one end of a common bidirectional transmit-receive optical path is tilted to divert any transmit signal back-reflected from such end out of such path. The other end of the transmit-receive path is affiliated with signal receiver and transmitter means via a beam splitter.