Barry M Belgorod: Spectacle lens having continuously variable controlled density and fast response time. Schwartz & Weinrieb, July 21, 1981: US04279474 (201 worldwide citation)

A spectacle lens comprises a liquid crystal layer and electrode assembly sandwiched between a pair of identically curved glass plates and layers of polarization material on the outer surfaces of the plates. The optical density of the lens is controlled by applying across the electrodes variable duty ...

Richard P Eckberg, Ronald W LaRochelle: Ultraviolet curable epoxy silicone coating compositions. General Electric Company, Michael J Doyle, John L Young, Philip L Schlamp, July 21, 1981: US04279717 (148 worldwide citation)

Epoxy functional diorganosiloxane fluids are combined with bis-aryl iodonium salts, particularly linear alkylate bis-dodecylphenyl iodonium salts to form a silicone coating composition effective for rendering surfaces non-adherent to other surfaces which would normally adhere thereto, and which will ...

Michel Vert, Francois Chabot, Jean Leray, Pascal Christel: New prosthesis parts, their preparation and their application. Agence Nationale de Valorisation de la Recherche, Institut National de la Sante et de la Recherche Medicale, Cushman Darby & Cushman, July 21, 1981: US04279249 (141 worldwide citation)

Osteosynthesis parts are made of an absorbable polymer composition consisting of a matrix of lactic acid homopolymer, or a copolymer very high in lactic acid units, having discrete reinforcement elements embedded therein. The reinforcement elements are made of glycolic acid homopolymer or copolymers ...

Randall K B Chun, Donn E Larsen: Digital data communication system. The Boeing Company, David G Pursel, Robert L Gullette, July 21, 1981: US04280221 (137 worldwide citation)

A digital data communication system including a data source and a source interface, a digital data bus, for transferring encoded information from the data source to one or more receivers, each having a receiver interface. The source interface is adaptable for controlling the rise and fall times of t ...

Donald H Wells: Variable mutual transductance tuned antenna. William Preston Hickey, July 21, 1981: US04280129 (136 worldwide citation)

An electromagnetic tuning device for RF circuits and particularly loading coils for antennas is disclosed. The preferred devices have a coil which produces a generally torroidal shaped electromagnetic field that is intensified by either a core of ferromagnetic material or a second coil inside the ot ...

E Roy John: Rapid automatic electroencephalographic evaluation. Eliot S Gerber, July 21, 1981: US04279258 (134 worldwide citation)

The rapid automatic examination and evaluation of large numbers of subjects by electroencephalography is accomplished by removably securing electrodes to the head of each subject under test to provide a plurality of channels of brain wave information corresponding to different head regions. The brai ...

Jan D Miller: Air-sparged hydrocyclone and method. University of Utah, July 21, 1981: US04279743 (126 worldwide citation)

An air-sparged hydrocyclone apparatus and method, the apparatus including a substantially hollow, cyclone body having a cylindrical section and a downwardly oriented conical section. An inlet, an overflow and an underflow are also provided in the cyclone body. At least a portion of the wall of the c ...

Robert A Administrator of the National Aeronautics and Space Administration with respect to an invention of Frosch, Taylor G Wang, Daniel D Elleman: Method and apparatus for producing concentric hollow spheres. Monte F Mott, John R Manning, July 21, 1981: US04279632 (104 worldwide citation)

Hollow spheres with precisely concentric inner and outer spherical surfaces are formed by applying vibrations to a nonconcentric hollow sphere while it is at an elevated temperature at which it is fluid or plastic, the vibrations producing internal flows which cause the inner and outer surfaces to b ...

Robert L Eisenhart: Electrical coupler. Jackson Jones & Price, July 21, 1981: US04280112 (104 worldwide citation)

An electrical coupler for transmitting high frequency electrical signals from a coaxial transmission to a microstrip transmission line. The coupler is adapted to match the characteristic impedance of the two media and the electromagnetic field patterns of the two media at the interfaces therewith. T ...

Michael T Martin: X-ray scaling catheter. George W Finch, July 21, 1981: US04279252 (99 worldwide citation)

A standard angiography catheter is modified by placing at least two radio opaque markers therein a known distance apart adjacent its distal end to enable the calculation and correction of errors due to X-ray magnification.