Patents Assigned to American Telephone and Telegraph Company AT&T Bell Laboratories
  • Patent number: 5076096
    Abstract: Various methods have been proposed for measuring the viscosity of thermosetting polymers. It has been found that these method are generally inaccurate. A test which avoids the inaccuracies of previous techniques is proposed. In this test the heated thermosetting resin is forced at a known flow rate through a runner and through a capillary tube at the end of the runner. By measuring the pressure differential across the capillary a meaningful measure of viscosity is obtained.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: December 31, 1991
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Lee L. Blyler, Jr., Philip Hubbauer, Gerhard W. Poelzing, Richard C. Progelhof
  • Patent number: 4942574
    Abstract: A high capacity metropolitan area network (MAN) is described. Data traffic from users is connected to data concentrators at the edge of the network, and is transmitted over fiber optic data links to a hub where the data is switched. The hub includes a plurality of data switching modules, each having a control means, and each connected to a distributed control space division switch. Advantageously, the data switching modules, whose inputs are connected to the concentrators, perform all checking and routing functions, while the 1024.times.1024 maximum size space division switch, whose outputs are connected to the concentrators, provides a large fan-out distribution network for reaching many concentrators from each data switching module. The data switching modules chain groups of incoming packets destined for a common outlet of the space division switch so that only one connection in that switch is required for transmitting each group of chained packets from a data switching module to a concentrator.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: July 17, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Bruce R. Zelle
  • Patent number: 4942442
    Abstract: Radiation-induced effects discovered in layered structures of conductor and semiconductor materials are utilized in radiation-sensitive devices such as, e.g., highly linear as well as highly nonlinear position sensors. Such devices includes a structure of alternating layers of conductor and semiconductor materials, and electrical contacts are provided between which a radiation-induced voltage appears. Among suitable layer materials are silicon and titanium, and resulting devices are sensitive to electromagnetic as well as to particle radiation.
    Type: Grant
    Filed: April 27, 1989
    Date of Patent: July 17, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Clyde G. Bethea, Daniel Brasen, Barry F. Levine, Ronald H. Willens
  • Patent number: 4918031
    Abstract: Anisotropic plasma etching is accomplished utilizing a helical resonator operated at relatively low gas pressure. The use of this combination yields an extremely high flux of ionic species with resulting rapid anisotropic etching. A helical resonator in conjunction with suitable precursors is also quite useful for plasma induced deposition.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: April 17, 1990
    Assignee: American Telephone and Telegraph Company,AT&T Bell Laboratories
    Inventors: Daniel L. Flamm, Dale E. Ibbotson, Wayne L. Johnson
  • Patent number: 4916522
    Abstract: An integrated circuit package uses an encapsulant frame which prevents the encapsulant used to seal the integrated circuit chip from the ambient atmosphere from flowing to unwanted areas and to permit the encapsulant to be deposited with a controllable depth.
    Type: Grant
    Filed: April 21, 1988
    Date of Patent: April 10, 1990
    Assignee: American Telephone and Telegraph Company , AT & T Bell Laboratories
    Inventor: Charles Cohn
  • Patent number: 4915472
    Abstract: There is disclosed a connector for two terminal plugs having bores in which are recieved respective optical fibers having free ends terminating at the front ends of such plugs. The connector comprises a longitudinal sleeve of sheet metal having a bottom, back and top and a longitudinal opening at its front. The sleeve contains a guide disposed alongside a longitudinal passage through the sleeve for receiving the two plugs end-to-end. The sleeve top is divided by lateral slits into two central resilient fingers and two resilient tabs at the sleeve ends. The fingers exert forces to press the end-to-end plugs against the guide to align them, while the tabs exert greater forces on the guide to maintain it clamped with the sleeve. The slits extend part way down the back of the sleeve, the guide has beveled edges, and the mentioned opening is bordered by top and bottom lips adapted to be pried apart by a pliers tool.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: April 10, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Wing S. Liu
  • Patent number: 4913659
    Abstract: A terminal board has a base plate and rows and columns of terminals upstanding from such plate. Each terminal comprises (a) an insulative hollow post (b) a metallic terminal strip in the post and having a pair of tangs separated by a contact gap and projecting above part of the post, and (c) a hollow cap fitted on such post to enclose such tangs and gap and shiftable on such post between up and down detained positions. The cap on opposite sides has entrance and exit holes aligned diagonal to such rows and columns, with the entrance hole having an inwardly downward slant and the exit hole being horizontal. With the cap in up position, an insulated lead is fed into the entrance hole and then passed partly or fully through the exit hole which initially impedes full passage through it of the lead.The cap is then pushed on the post to down position to cause the lead to be driven against the tangs and into the contact gap such that the lead's insulation is cut and the metallic core of the lead contacts the tangs.
    Type: Grant
    Filed: June 29, 1989
    Date of Patent: April 3, 1990
    Assignee: American Telephone and Telegraph Company, AT & T Bell Laboratories
    Inventor: Clarence E. Doyle
  • Patent number: 4914081
    Abstract: Processes are described for electroplating metal or alloy on superconducting oxides using either a nonaqueous bath or aqueous bath with suitably applied potential. Articles made in accordance with the electroplating process are also described.
    Type: Grant
    Filed: January 15, 1988
    Date of Patent: April 3, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Barry Miller, Joseph M. Rosamilia
  • Patent number: 4914667
    Abstract: In the interest of ease of manufacture, hybrid lasers of distributed-Bragg-reflector type are preferred for use as light sources in optical communications. Such lasers are made to operate away from mode instabilities by adjusting a laser parameter such as, e.g., laser temperature, thereby assuring highly error-free transmission. Alternatively, by suitable design of the Bragg reflector it is possible to render mode instability of negligible influence on error rate.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: April 3, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Greg E. Blonder, Charles H. Henry, Rudolf F. Kazarinov, Nils A. Olsson, Kenneth J. Orlowsky
  • Patent number: 4913517
    Abstract: A communications cable (20) comprising a core (22) of at least one transmission media and a plastic jacket (34) includes provisions for preventing the movement of water within the cable. The cable includes a strength system (32) including longitudinally extending fibrous strength members (32-33) having a relatively high modulus and having water blocking provisions. In one embodiment, each fibrous strength member is treated with a superabsorbent liquid material which when dry fills interstices and covers portions of the exterior thereof. In another embodiment, a filamentary strand material comprising a water swellable fibrous material is wrapped about each fibrous strength member.
    Type: Grant
    Filed: July 11, 1988
    Date of Patent: April 3, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Candido J. Arroyo, Jill B. Fluevog, Krishnaswamy Kathiresan, Parbhubhai D. Patel
  • Patent number: 4912764
    Abstract: An speech analysis and synthesis system where pitch information for excitation is transmitted during voiced segments of speech and modified residual information for excitation is transmitted during unvoiced speech segments along with linear predictive coded (LPC) parameters. The speech analysis portion of the system uses a pitch detection circuit to determine when the speech is voiced or unvoiced and to calculate the pitch information during voiced segments. A multi-pulse excitation forming circuit generates the modified residual signal which is obtained from the cross correlation of the residual signal and the LPC-recreated original signal. The pitch detection circuit controls a multiplexer which selects either the output of the multi-pulse excitation forming circuit or the output of the pitch detection circuit for transmission as the excitation information with LPC parameters to the synthesizer portion of the system.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: March 27, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Walter T. Hartwell, Joseph Picone, Dimitrios P. Prezas
  • Patent number: 4912347
    Abstract: A circuit is disclosed which converts CMOS logic input signals to ECL output signals. A pair of FETs, arranged as a conventional CMOS inverter, responds to the CMOS logic input signals and drives a bipolar transistor operating as a voltage follower. The emitter of the bipolar transistor serves as the output of the buffer providing the ECL output signals. A resistor having a predetermined resistance couples between a voltage source and the base of the bipolar transistor. First one of the pair of FETs couples a constant current source to the resistor and the base of the bipolar transistor when the buffer is supplying an ECL logical "zero" logic signal. The current from the current source passing through the resistor establishes the ECL logical "zero" output voltage. Second one of the pair of FETs shunts the resistor when the buffer is supplying an ECL logical "one" output, allowing faster transitioning of the output of the buffer from an ECL logical "zero" to a logical "one".
    Type: Grant
    Filed: August 25, 1987
    Date of Patent: March 27, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Bernard L. Morris
  • Patent number: 4910452
    Abstract: Efficient high frequency operation of magnetic devices is achieved by utilizing ferrites that have a low power dissipation hysteresis characteristic and by designing these magnetic devices to operate within an operational range where all applied magnetic forces to the magnetic core have a substantially linear constant permeability response. Within this operational range the hysteresis loop of the selected ferrite material approximates an ellipse with very little area encompassed between the increasing and decreasing B-H locus of the hysteresis loop. The cyclic energy dissipation is significantly reduced as compared to conventional magnetic operations and high frequency operation can be achieved with very high efficiencies.
    Type: Grant
    Filed: May 16, 1989
    Date of Patent: March 20, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Frederick T. Dickens, Felipe Sarasola, Norman G. Ziesse
  • Patent number: 4909816
    Abstract: A preform for fabrication of a glass fiber optical transmission line is prepared by chemical reaction of vapor ingredients within a glass tube. Reaction, which may be between chlorides or hydrides of, for example, silicon and germanium with oxygen, occurs preferentially within a constantly traversing hot zone. Flow rates and temperature are sufficient to result in glass formation in the form of particulate matter on the inner surface of the tube. The particulate matter deposits on the tube and is fused with each passage of the hot zone. Continuous rotation of the tube during processing permits attainment of higher temperatures within the heated zone without distortion of the tube.
    Type: Grant
    Filed: July 26, 1983
    Date of Patent: March 20, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: John B. MacChesney, Paul B. O'Connor
  • Patent number: 4909592
    Abstract: A communications cable comprising a core of transmission media such as optical fibers, for example, disposed in a core tube and a sheath system (32) includes provisions for preventing the movement of water within the cable core. Water blocking provisions (26) are disposed in the core tube and may comprise a tape or a yarn, for example, or both. The tape may comprise substrate tapes between which is disposed a superabsorbent material in powder form which upon contact with water swells and inhibits the further movement of the water. In another embodiment, a water swellable yarn may extend longitudinally linearly with the optical fibers in the core.
    Type: Grant
    Filed: September 29, 1988
    Date of Patent: March 20, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Candido J. Arroyo, Paul F. Gagen
  • Patent number: 4908935
    Abstract: In a hybrid integrated circuit encapsulation process, each lead array (14) is encompassed by an elongated C-shaped barrier member (17) which clamps onto the portions of the lead array adjacent the substrate (11); that is, opposite sides of a slot (18) in the barrier member grasp opposite sides of the leads. Thereafter, the uncured RTV silicone (15) is dispensed onto the substrate, flows over and encompasses chips (12) mounted on the surface of the substrate and is prevented from flowing along the leads (14) by the C-shaped members (17), each of which, due to its configuration, constitutes a barrier to fluid flow, either along the length of the various leads or over the top of the C-shaped member. In one embodiment, levers (19) may be integrated onto the C-shaped member opposite the substrate to aid in prying open the slot to permit the leads to be easily inserted into the C-shaped member.
    Type: Grant
    Filed: March 22, 1989
    Date of Patent: March 20, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Brent J. Blumenstock
  • Patent number: 4907259
    Abstract: A call appearance reservation arrangement where any number of the call appearances of a directory number are reservable, and where a reservation type is defined for the directory number such that calls to and from the reserved call appearances are processed in accordance with one of a number of possible reservation types, such types for example including: (1) origination only, (2) termination only, and (3) origination and priority termination only.
    Type: Grant
    Filed: November 6, 1987
    Date of Patent: March 6, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Dewey A. Frech
  • Patent number: 4904036
    Abstract: Optoelectronic chips, such as Group III-V compound lasers and photodiodes, are mounted on a single-crystal silicon base, and are optically interconnected to one another by silica waveguides and couplers integrally formed on the base. Integrated circuit chips to provide electronic function are also mounted on the base. Various schemes for optically coupling and aligning lasers, photodiodes and optical fibers to the waveguides are described. Also described is the use of a single-crystal silicon lid, which serves to provide optical and electrical isolation between chips on the base, as well as a plug-in arrangement in which the edges of the base are adapted to receive parallel guide rods.
    Type: Grant
    Filed: March 3, 1988
    Date of Patent: February 27, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Greg E. Blonder
  • Patent number: 4904043
    Abstract: A dual wavelength optical coupler is disclosed which provides either bidirectional or unidirectional communication at different wavelengths over a single fiber. The coupler utilizes a dichroic filter and a set of three lenses to achieve dual wavelength communication. Additional blocking filters may be incorporated to decrease the degree of optical crosstalk present in the system.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: February 27, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Rudolph C. Schweizer
  • Patent number: RE33266
    Abstract: A folded bit line configured DRAM, with standard even and odd rows of memory cells, also includes spare even and odd rows of memory cells which can be substituted for standard rows found to have defective cells or interconnections. Each of the decoders associated with a standard row includes provision for being disconnected if found to be associated with a defective row. One common spare decoder is associated with one spare even and one spare odd row of memory cells. Each spare decoder is designed normally to be deselected for any address but to be able to assume the address of any disconnected standard row. Disconnection of a standard decoder and substitution of a spare decoder with the appropriate even or odd row are made possible by appropriate inclusion of fusible links which are selectively opened by laser irradiation. The use of one spare decoder with both an even and odd row serves to reduce the number of needed spare decoders and thus reduces overall chip size.
    Type: Grant
    Filed: January 15, 1987
    Date of Patent: July 17, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventor: Austin C. Dumbri