Abstract: This circuit divides power from an input source equally among N different paths, where N is an arbitrary number. These individual path powers can then be amplified separately to take advantage of the full output power ratings for the individual amplifiers, then the outputs from the amplifiers are combined. A combiner circuit, which is the reverse of the divider circuit, then combines the individual powers to a single output. In each of the combiner and divider circuits, the phase angles of the output ports vary from each other by 90 degrees sequentially down the entire chain of N-1 couplers. Each combiner and divider network utilizes N-1 series-connected couplers, preferably interdigitated ones. The interdigitated couplers utilize preselected power division ratios based upon N.

Abstract: This device provides for a substantially orthogonal transition or connection point between a strip transmission line configuration (one conductor, or two conductors sandwiched around a dielectric support, positioned in air between two ground planes such as might be used in a microwave antenna feed network) and a coaxial line section. The particular construction of the "side-launch transition" suppresses spurious parallel plate modes, and, in the case of two conductors surrounding a dielectric, trapped modes which occur between the two conductors. A U-shaped upper "dam" and corresponding lower "dam," electrically interconnected at several points, surround the termination of the stripline conductor(s) and provide suppression of parallel plate molding at the transition. In the case of two conductors surrounding a dielectric, electrical interconnection at the terminal point of the stripline conductors suppresses the trapped modes before they can be launched.

Abstract: This on-line circuit estimates the bit error rate (BER) of a binary data signal stream in the presence of noise uncorrelated with the signal. For a binary data signal having two states, e.g., plus V and minus V biased around a specified reference level (REF), the circuit counts the number of instances in which the received signal deviates more than 2V from the reference level. This accumulated count gives an accurate estimate of the BER over several orders of magnitude variation of the BER. One embodiment counts just the deviations in a positive direction. This circuit functions independently of any bit pattern and can be used for on-line monitoring without decreasing the information carrying capability of the link. The time required to accumulate a statistically significant sample is the same as for a direct comparison between sent and received bits.

Abstract: In a tomographic apparatus and method for reconstructing two dimensional planar slices from linear projections of non-absorbed and non-scattered radiation useful in the fields of medical radiology, microscopy, and non-destructive testing, a beam of radiation in the shape of a fan is passed through an object lying in the same quasi plane as the radiation source and non-absorption and non-scatter thereof is recorded on oppositely situated detectors aligned with said source. There is relative rotation between the source-detector configuration and the object within the quasi-plane. Periodic values of the detected radiation are taken, convolved with certain functions, and back-projected to produce a two-dimensional output picture on a visual display illustrating a facsimile of the object slice. A series of two-dimensional pictures obtained simultaneously or serially can be combined to produce a three-dimensional portrayal of the entire object.

Abstract: An apparatus and method for reconstructing data, a fan beam of radiation is passed through an object, which beam lies in the same quasi-plane as the object slice to be examined. Radiation not absorbed in or scattered by the object slice is recorded on oppositely situated detectors aligned with the source of radiation. Relative rotation is provided between the source-detector configuration and the object. Reconstruction means are coupled to the detector means, and may comprise a general purpose computer, a special purpose computer, and control logic for interfacing between said computers and controlling the respective functioning thereof for performing a convolution and back projection based upon non-absorbed and non-scattered radiation detected by said detector means, whereby the reconstruction means converts values of the non-absorbed and non-scattered radiation into values of absorbed radiation at each of an arbitrarily large number of points selected within the object slice.

Abstract: In an apparatus and method for reconstructing data, a beam of radiation in the shape of a fan is passed through an object lying in the same quasi plane as the radiation source and non-absorption and non-scatter thereof is recorded on oppositely situated detectors aligned with said source of radiation. There is relative rotation between the source-detector configuration and the object within the quasi-plane. Periodic values of the detected radiation are taken, convolved with certain functions, and back-projected to produce a two-dimensional output picture on a visual display illustrating a facsimile of the object slice. A series of two-dimensional pictures obtained simultaneously or serially can be combined to produce a three-dimensional portrayal of the entire object.

Abstract: In an instrument for reconstructing computerized tomograms utilizing penetrating radiation, typically X or gamma radiation, an apparatus and technique are disclosed for removing spectral artifacts and utilizing spectral effects to create output pictures which represent facsimilies of the distribution of molecules according to atomic number and electron density within the object being pictured. Combinations of these pictorial representations are also obtained. Reconstruction errors caused by panchromaticity in the radiation source are avoided. Attenuation within the object by means of photoelectric absorption, Compton scattering and Rayleigh scattering are isolated and analyzed separately. Techniques are disclosed for treating source beams which are arbitrarily thin or of a finite thickness.

Abstract: Closely spaced windings of wire are laid down on a revolving drum and retained in place by an adhesive substrate previously mounted on the drum. The cylinder of wire with an adhesive substrate which is formed is cut and removed from the drum and spread into a flat sheet. The wire side of the sheet is placed in contact with the epoxied surface of an elongated plate. The plate traverses the wire sheet in a strip proximate one terminal edge thereof dividing the sheet into a major portion which will ultimately form the lead wires to the head and a minor portion which is trimmed off in later step. After the epoxy has dried, the adhesive substrate is removed and the newly exposed side of the wire is placed in contact with the epoxied surface of a second elongated plate. The two plates form an elongated sandwich containing the wire embedded in epoxy. The ends of the wire forming the minor portion are trimmed and the end surface of the sandwich is polished to form the finished recording head.

Abstract: Image detection and intensification under exceedingly low levels of illumination, as of 10.sup.-2 to 10.sup.-5 foot candles, is made possible by combining the advantages of conventional inverter image tubes with those of recently developed microchannel plate wafer tubes. Under environmental conditions necessitating an overall luminous gain of 50,000, a microchannel plate wafer tube is coupled to the output of a conventional inverter image tube permitting cone viewing by operating personnel. This is made possible by operating the microchannel plate wafer tube at low electron gain levels such that microchannel plate noise characteristics are maintained at acceptable levels. The objectives of reduced size, weight, and power consumption approximating that of a single stage of the presently used three stage night vision systems are thereby achieved.

Abstract: In a method and apparatus for electrostatically recording on a dielectric coated sheet, a recording head carrying a stylus array is spaced apart from the sheet to form an ionization gap. A charge image is transferred to the sheet by applying an activating voltage between selected styli and a back-up electrode. All styli receive a D.C. bias voltage and selected styli additionally receive "write" pulse voltage. The sum of the bias and write pulse voltages exceeds the threshold breakdown voltage of the gap to ionize the air in the gap under the selected styli. The charge image, created by the ionized air, is subsequently toned to form a visible image. The magnitude of the threshold breakdown voltage is dependent on the length of the gap and the required magnitude of the write pulses depends in part on how accurately the length of the gap is maintained constant.

Abstract: In an image tube, a microchannel electron multiplier plate is disposed between the photocathode and a cathodoluminescent output screen for multiplying the electron current of electron images. Electrodes are deposited upon the input and output face of the microchannel electron multiplier plate. On the output face the electrode is deposited into the ends of the microchannels to a distance of approximately 2 diameters of the individual channels. A semiconductive material, such as zinc sulphide, is deposited over the output electrode in the output ends of the microchannels for causing the secondary electrons emitted from the end portions of the microchannels to show a narrow energy spread, whereby the resolution of the intensified output image is enhanced.

Abstract: In an electrophotographic camera, a photon image to be recorded is focused through an optically transparent substrate and transparent electrode onto the back surface of a photoconductive layer. The charge-retentive surface of an electrographic recording paper is disposed adjacent the photoconductive layer and the conductive backing of the paper is connected to an electrode for impressing a charge transfer potential across the photoconductor layer and the charge-retentive layer of the paper. When the potential is impressed across the photoconductor, increased conduction caused in the photoconductor by the photon image to be recorded are establish a charge transfer to the charge-retentive surface of the recording paper to form a charge image of the object to be recorded. The charge image is subsequently developed by applying charged toner particles to the image for developing same.

Abstract: An electrophotographic camera is disclosed. The camera employs a novel photoconductive plate, the composition of which is disclosed together with the method of making same. In the camera, a photo image to be recorded is focused thrugh an optically transparent substrate and transparent electrode onto the back surface of a photoconductive layer. The charge-retentive surface of an electrographic recording paper is disposed adjacent the photoconductive layer and the conductive backing of the paper is connected to an electrode for impressing a charge transfer potential across the photoconductor layer and the charge-retentive layer of the paper. When the potential is impressed across the photoconductor, electrons liberated in the photoconductor by the photon image to be recorded are transferred to the charge-retentive surface of the recording paper to form a charge image of the object to be recorded. The charge image is subsequently developed by applying charged toner particles to the image for developing same.

Abstract: Apparatus for measuring gas comprising a gas sensing unit having a gas inlet membrane and being evacuated by a sputter ion pump via a restrictive conductance. Said conductance has a very low value relative to the pumping speed of the pump, whereby a change in the pumping speed of the pump causes substantially no change in the pumping speed with which the gas sensing unit is evacuated, so that the output signal of said gas sensing unit is a true reflection of the gas entering said inlet, without distortion which would otherwise be caused by changes in pumping speed of said pump.