Abstract:
A body of semiconductor material having first and second opposed faces, and containing a region of N type conductivity and a region of P type conductivity separated by a P-N junction. The N type region contains a central portion extending inward from one face partially through the body toward the second face, and a peripheral portion extending completely through the body with its resistivity increasing toward the second face relative to the remainder of the N type region adjacent the P-N junction. The peripheral portion encloses the P type region and extends the P-N junction to the second face where it has the least chance for voltage breakdown.
Abstract:
The exciter, mounted closely behind the deflection yoke on the neck of the tube, has three pairs of external coils which are respectively associated with three pairs of internal pole pieces and are enveloped by a ferromagnetic core.
Abstract:
A method of rebuilding a cathode ray tube, including the penetration of a metallic part of the tube by means of a pointed tool, for example. Defective parts of the vented tube can be replaced or the re-usable parts thereof can be reclaimed. The opening in the metallic part of the tube can be hermetically sealed with a frit material or by sealing to the metallic part a pin that is inserted in the opening therein.
Abstract:
A method for preparing a screen structure comprising a lightabsorbing layer or matrix having therein an array of discretelysized holes filled with luminescent material. A stencil having an array of opaque areas, which areas are larger than the desired holes, is produced on a supporting surface. A photopolymeric film is deposited over the stencil and supporting surface, and light is passed through the surface and stencil, thereby exposing the film. The light in the film is scattered so that the exposed areas extend behind the opaque areas of the stencil producing unexposed areas in the film which are substantially the same size as the desired holes. The unexposed areas of the film and the opaque portions of the stencil are removed, while the exposed areas of the film are retained in place. The retained exposed areas are rendered light-absorbing and the holes therein are filled with luminescent material.
Abstract:
A high power frequency device such as a thyristor or transistor comprises a monolithic body consisting of an emitter assemblage laminated to a base-collector assemblage. The emitter assemblage is a semiconductive wafer of given conductivity type having a plurality of mesas adjacent one surface; a high resistivity ballast layer in each mesa; an insulating film on said one surface and around each mesa; and a layer of high conductivity material, such as heavily doped semiconductive material of opposite conductivity type, on said insulating film over said one surface and surrounding said mesas, the surface of said high conductivity layer being co-planar with the top of said mesas. The base-collector assemblage is a semiconductive wafer which includes at least two layers of mutually opposite conductivity types, the surface of one layer being planar and constituting a major surface of said body.
Abstract:
A test waveform which consists of n separate test signals during n successive time intervals, respectively, is applied to one or more units under test. The response of a unit to a particular one of the signals is ascertained by sensing the output produced by that unit only during times synchronous with times that the test signal is present.
Abstract:
A method for making a multialkali photocathode includes simultaneous evaporation of sodium and antimony alternately with simultaneous evaporation of potassium and antimony. The disclosure includes a photocathode made by the method described.
Abstract:
A radial heat pipe has a plurality of radial struts covered with capillary lining which extend from an outer cylindrical heat output wall to an inner cylindrical heat input wall to assist in returning a working fluid from the heat output wall to the heat input wall. A deformable metallic lining is attached to the outside of the cylindrical heat input wall to provide a close fit with and a good thermal path from a heat source member to the heat input wall. The heat pipe also has a tube extending down its central axis which permits force to be applied to the heat source member to separate the heat source member from the heat pipe.
Abstract:
An electron beam excited laser element including a body of a material which is capable of generating light when excited by an electron beam and having a pair of opposed, substantially parallel, spaced surfaces. A partially reflective layer is provided on one surface of the body to allow emission of a portion of the light from the body. A metal layer is provided over the other surface of the body with at least a portion of the metal layer being spaced from the surface of the body. The metal layer is substantially fully light reflective but transmits the electrons of the electron beam with little loss. When an electron beam is directed at the spaced portion of the metal film, the material of the body is excited to generate light which is emitted through the partially reflective layer. The spacing of the metal layer from the surface of the body reduces the electron beam power necessary to cause lasing of the element.
Abstract:
Apparatus for automatically disposing a record web for operation by the transport of a recorder-reproducer system. The web is first formed into a given shape which approximates the shape of the operating path defined by the transport elements. The web is then interlaced with the elements of the transport. To retract the web, the reverse sequence is utilized.