Abstract: A nuclear imaging system in which a substantially on-axis Fresnel zone plate positioned between a source of nuclear radiation in living tissue and a spatial detector is moved in a predetermined time sequence in synchronism with motion of a bar pattern formed at the spatial detector output to improve suppression of unwanted spatial frequency components and to facilitate production of an image of the nuclear source.

Abstract: A membrane type dielectric storage target formed from a thin refractory dielectric film is stretched to form at least a one-sided surface, a first surface portion contacting a conductive wire mesh, a second surface portion having areas coated with conductive material imaging the mesh of the first surface portion. The method contemplates forming the conductive image on the second surface portion by photo-resist, decoration, and breakdown techniques.

Abstract: A semiconductor structure having a surface insulating layer formed as a grid with charges implanted in the insulating material to prevent inversion and, hence, channeling between adjacent semiconductor regions, preferably for use in nonblooming vidicon. The method of manufacturing such a structure uses ion implantation to create immobile positive charges in a grid pattern in an insulating layer in regions spaced from the interface between the insulating layer and the semiconductor body. The insulating layer is of sufficient thickness that substantially all of the charge sites in the insulating layer are separated from the outer surface of the insulator by a sufficient distance to effectively prevent a negative electric field from reaching into the silicon.

Abstract: A coupled ion laser operating at a frequency determined by the energy levels characteristic of the coupling of a lanthanide or actinide group ion with an iron group ion in an orthoaluminate material, such as yttrium orthoaluminate, is described in which low threshold high efficiency starting operation at predetermined frequencies in the region of eye safety is provided.

Abstract: A digital character generator with minimal storage requirements for use in random access display systems. Each character or symbol is made up of patterns of straight line segments called macro-strokes. Each macro-stroke in turn is made up of a predetermined number of connected portions or micro-strokes lying in a straight line. Each micro-stroke is of substantially the same length independent of the number of micro-strokes in a macro-stroke and of the directional orientation of the macrostroke. To store a character or symbol each macro-stroke is divided into its micro-strokes and the micro-strokes resolved into X and Y components. The X and Y components are stored along with the number of micro-strokes in the particular macro-stroke. Along with this information is stored the address and memory of the next macro-stroke within the character or symbol.

Abstract: A temperature compensated acoustic surface wave device, such as a surface wave delay line is provided in which temperature compensation is provided by the deposition of an interdigital electrode structure on a substrate with an overlay film surface of piezoelectric material of a predetermined thickness. A double substrate arrangement is also disclosed in which the interdigital electrode structure is deposited upon the surface of a non-piezo-electric layer which in turn is placed upon the surface of a piezoelectric substrate.

Abstract: A laser heterodyne system is disclosed wherein received reflections of a beam of coherent light are amplified in a laser. The amplified received reflections are heterodyned with the light produced by the laser and the resulting beat frequency is detected using a photodetector. A controller, responsive to the beat frequency, controls, in one case, the frequency of a transmitting laser, and hence the frequency of the received light, and, in another case, the frequency of the light produced by the amplifying laser so that, in either case, the difference between the frequency of the received light and the frequency of the light produced by the amplifying laser is adjusted to maximize the amplification of the received light by the amlifying laser prior to detection by the photodetector.

Abstract: A semiconductor integrated circuit in which accurate location of emitter contacts on diffused emitter regions is achieved by using an apertured multilayered mask on the surface of a semiconductor body through which the impurity forming the emitter region is diffused into the body from an oxidizing atmosphere such that the emitter region diffuses laterally to form junctions beyond the edges of said apertures and beneath the mask for a distance which is a function of the depth of the junctions and the coating formed during the diffusion process is removed by R.F. sputtering which removes the emitter oxide without substantially undercutting the oxide layer beneath the nitride barrier layer of the emitter mask so that the junction on the surface of the semiconductor body produced by the lateral diffusion of the emitter region remains covered by the surface passivating oxide layer. Structures having microminiature emitter areas and depths with and without preferentially etched isolation regions are disclosed.

Abstract: A utensil for heating circular elongated objects with microwave energy is disclosed for securing browning and searing of the exterior surfaces. A plurality of searing members of a curved tapered substantially V-shaped configuration encompass a portion of or all of the elongated object to be heated. The searing means are supported on a microwave transparent frame of a plastic material.

Abstract: A microwave browning plate utilizing members of a relatively low dielectric constant material is provided having a conductive coating on three sides with a load supported on the uncoated side. The induced currents in the conductive material provides for current induced in the dielectric material. An exponentially decreasing fringing electric field is provided as a standing wave adjacent to the uncoated side. A low dielectric constant material may be utilized with the conductive coating and an overall height of one-quarter of a wavelength will result in a thinner microwave plate. Means are provided for restricting the current flow to a desired mode.

Abstract: In a gamma camera having an array of photomultipliers coupled via pulse shaping circuitry and a resistor summing and weighting circuit to a display for forming an image of a radioactive target, the improvement being a modulation circuit for reducing the intensity of points on the display located at positions corresponding to positions of the photomultipliers for removing an apparent image of the array.

Abstract: A signal display system having a visual display and a display signal generator in which a semiconductor junction target has a high conductivity P layer, a low conductivity N layer, and a surface layer of insulating material having holes in the shape of letters or other characters. The target semiconductor junction is reverse biased so that when an electron beam striking the target is scanned over the character apertures, it will produce carrier multiplication in the target and an output signal several orders of magnitude greater than a conventional monoscope. The same principle may be used for a camera pickup tube when beam electrons returning from a light sensitive target are multiplied on striking a reverse biased junction target.

Abstract: In a navigation system in which a beam of radiation is utilized for communicating information to a vehicle, such as an aircraft approaching a landing strip, there is provided a pseudo-noise generated binary code having sequentially generated bits ordered in a sequence of nonrepeating subsequences with each of these bits uniquely representing a value of a coordinate describing the position of the beam of radiation. For example, with an azimuthally scanned beam of radiation, each bit in the code represents an increment in the azimuth angle while the digits of one of the subsequences is sufficient to uniquely determine the azimuth angle. An encoder and a decoder, each similarly structured with a shift register and feedback logic, are disclosed.

Abstract: An apparatus for activating a remote underwater device comprising detecting means responsive to incident acoustic waves provides signal indication of the presence or absence of predetermined frequencies thereof. A logic arrangement decodes only those signal indications indicating a joint presence of some of the pre-selected frequencies and the absence of others of the pre-selected frequencies. This discriminates signals against broad-band acoustic noise. The logic arrangement further includes means for activating the remote underwater device only if the decoded successive signal indications match a predetermined pattern. This further discriminates between a present received acoustic wave and a prior transmitted acoustic wave present because of multipath or reverberation. Lastly, a timing and gating means responsive to a first decoded signal indication couples the detecting means to the logic arrangement only at periodic intervals thereafter.

Abstract: A system for communicating a data channel composed of a multiplicity of telephone-type messages wherein the invention incorporates circuitry for modulating service channel data onto a carrier of the telephone channel data and for demodulating the service data without interfering with the telephone data. An inverse modulator driven by detected telephone data is utilized to recover a carrier which is then tracked by a tracking filter to recover the service data.

Abstract: A microwave transistor package which will accommodate large transistor chips as well as provide sufficient space for the addition of tuning capacitors or other circuits. The lead length inside of the package is minimized. A ceramic mounting pad is brazed to an underlying copper base and a nickel aperture plate is mounted around the mounting pad. The amount of ceramic material used is much less than in prior art devices. Tuning capacitors or other devices are mounted upon the top surface nickel spacer and connected to the transistor chip. In the preferred embodiment, the entire package is hermetically sealed.

Abstract: A radiographic imaging system for high energy radiation utilizing a detector of such radiation and a mask having regions relatively transparent to such radiation interspersed among regions relatively opaque to such radiation. A relative motion is imparted between the mask and the detector, the detector providing a time varying signal in response to the incident radiation and in response to the relative motion. The time varying signal provides, with the aid of a decoder, an image of a source of such radiation.

Abstract: A burner for burning a mixture of a combustible gas and air including a curved wall member provided with a multiplicity of ports distributed throughout a substantial area of the wall. The ports are arranged in an ordered pattern such that every port, with the exception of a few along the edges of the burner, is surrounded by a plurality of closely adjacent ports. The size of each port and the distance between adjacent port edges are such that the jets of the gas-air mixture which issue from the ports merge into a common body of such mixture and form a closed lower pressure pocket around each port below such common body. The outer edges of such pocket are located above the minimum ignition level of each port and below the normal outer flame reach distance of the burner for the gas-air mixture supplied to the burner. As a result the flame produced by the burner may be stabilized in either of two regimes or in a combination of both depending upon the rate at which the mixture is supplied to the burner.

Abstract: A temperature compensated acoustic surface wave device, such as a surface wave delay line is provided in which temperature compensation is provided by the deposition of an interdigital electrode structure on a substrate with an overlay film surface of piezoelectric material of a predetermined thickness. A double substrate arrangement is also disclosed in which the interdigital electrode structure is deposited upon the surface of a non-piezoelectric layer which in turn is placed upon the surface of a piezoelectric substrate.

Abstract: A safety interlock system is disclosed for microwave ovens or other high voltage electrical apparatus incorporating sensor means for detecting any malfunction. Means are provided for interrupting line input power or actuating a failure indicating device or a combination of both. Thermally actuated means, such as bimetallic or meltable elements, as well as circuit breakers, relays and fuses are described. The sensor means are associated with each of the interlocks and do not carry regular equipment-load current until such time as a malfunction of the companion interlock occurs. Replacement of the faulty equipment by authorized personnel and manual resetting of the interrupt or indicating means before the oven is energized again reduce the risk of accidental radiation, electrical shock or damage to the apparatus.