Patents Represented by Attorney, Agent or Law Firm Leo R. Reynolds
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Patent number: 6330081Abstract: A method and apparatus are provided for canceling crosstalk noise arising on signal lines output from an image sensor. More specifically, the crosstalk noise is canceled by a current mirror that is coupled to the signal line. The current mirror adjusts the voltage level on the signal line by drawing a current therefrom that is proportional to the amount and polarity of the crosstalk noise. The amount of crosstalk noise is determined by an amount of coupling within an A/D converter coupled to the signal lines. The current mirrors can further adjust the voltage on the signal line by drawing a current therefrom that is proportional to crosstalk arising due to a voltage level on another signal line. Such a current mirror allows pixel data to be conveyed to the A/D converter, via the signal lines, without imparting aberrations due to crosstalk noise.Type: GrantFiled: November 20, 1998Date of Patent: December 11, 2001Assignee: Agfa CorporationInventor: Frank Lynn Scholten
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Patent number: 4565940Abstract: A method and apparatus is disclosed in which a piezoelectric film is used to control or dampen vibrations in a mechanical system. Voltage of proper amplitude and phase is fed across the piezoelectric film to induce strain in the film of appropriate phase, amplitude and frequency to dampen beam vibrations of the mechanical system. The film may be applied directly to the mechanical system or an intermediate viscoelastic layer may be provided. Various control functions are described for determining the correct voltage to be applied to the film.Type: GrantFiled: August 14, 1984Date of Patent: January 21, 1986Assignee: Massachusetts Institute of TechnologyInventor: James E. Hubbard, Jr.
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Patent number: 4547622Abstract: An improved photovoltaic device in which a charge separation junction is provided over a charge confining heterojunction. The charge separation junction is a junction formed of an n.sup.+ -doped direct bandgap layer on a p-doped direct bandgap active layer. The charge confining heterojunction is formed by the interface of the active layer with a Back Surface Layer (BSL) of higher bandgap material than the active layer to provide a Back Surface Field (BSF). The percentage of Al in the layers may vary from Y=O to x.ltoreq.0.42. The structure applies to both crystalline and amorphous material.Type: GrantFiled: April 27, 1984Date of Patent: October 15, 1985Assignee: Massachusetts Institute of TechnologyInventors: John C. C. Fan, Ronald P. Gale
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Patent number: 4546500Abstract: A method and apparatus for producing a vessel-equivalent prosthesis is described. A contractile agent such as fibroblast cells, smooth muscle cells or platelets is incorporated into a collagen lattice and contracts the lattice axially around an inner core. After the structure has set, additional layers may be formed in an ordered manner depending on the intended function of the prosthesis. Alternatively, all the layers may be formed concurrently. A plastic mesh sleeve is sandwiched between layers or embedded within the smooth muscle cell layer to reinforce the structure and provide sufficient elasticity to withstand intravascular pressure.Type: GrantFiled: February 26, 1982Date of Patent: October 15, 1985Assignee: Massachusetts Institute of TechnologyInventor: Eugene Bell
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Patent number: 4525871Abstract: An electronic mixer is decribed which utilizes an optoelectronic switch formed from a semi-insulating substrate of indium phosphide doped with a deep level impurity and disposed intermediate a microstrip transmission line. One conductor of the transmission line has a small gap in its metallization. Upon illumination of the gap by laser pulses from a laser source which are absorbed near the semiconductor surface, a photo-generated electron-hole plasma forms thereby providing a conducting path across the gap. An RF signal to be mixed with a LO signal is coupled to one side of the switch. The LO signal controls the Laser source. The output of the switch is therefore the product of the RF and LO signal.Type: GrantFiled: February 3, 1982Date of Patent: June 25, 1985Assignee: Massachusetts Institute of TechnologyInventors: Arthur G. Foyt, Frederick J. Leonberger, Richard C. Williamson
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Patent number: 4518219Abstract: A three-dimensional optical waveguide is disclosed. This waveguide comprises a single crystal semiconductor layer grown upon an insulator which has an index of refraction lower than the semiconductor. The semiconductor layer has a thickness which provides confinement of light propagating in the semiconductor layer in the vertical direction. An effective larger index of refraction over a cross-sectional region of the semiconductor layer provides confinement of light in the lateral direction. This lateral confinement is achieved by side walls in the semiconductor layer which extend toward, but fall short of, the insulator layer.Type: GrantFiled: February 3, 1983Date of Patent: May 21, 1985Assignee: Massachusetts Institute of TechnologyInventors: Frederick J. Leonberger, Ivars Melngailis, Carl O. Bozler, Robert W. McClelland
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Patent number: 4442166Abstract: A selective-black absorber capable of operation at elevated temperatures and high efficiency as a solar energy absorber is described. A cermet of MgO/Au, MgO/Pt, and Cr.sub.2 O.sub.3 /Cr having high solar energy absorptance and low infrared energy emissivity is coated on a substrate having high infrared reflectivity such as Mo coated on stainless steel; Ni coated on Cu, or steel; aluminum, or steel. Typically an absorption coefficient of about 0.93 with an emissivity of about 0.09 is obtained and operation at a temperature of 300.degree.-400.degree. C. is possible depending on the cermet and substrate materials.Type: GrantFiled: January 21, 1982Date of Patent: April 10, 1984Assignee: Massachusetts Institute of TechnologyInventor: John C. C. Fan
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Patent number: 4420873Abstract: A method for fabricating three-dimensional optical waveguides is disclosed. In this method, a single crystal semiconductor layer is grown upon an insulator which has an index of refraction lower than the semiconductor. The semiconductor layer is deposited to a thickness which provides confinement of light propagating in the semiconductor layer in the vertical direction. An effective larger index of refraction over a cross-sectional region of the semiconductor layer is then formed to provide confinement of light in the lateral direction. In the preferred method, the growth of single crystal semiconductor upon the insulator is achieved by a vapor-phase lateral epitaxial overgrowth technique.Devices fabricated according to the method are also disclosed.Type: GrantFiled: January 25, 1980Date of Patent: December 20, 1983Assignee: Massachusetts Institute of TechnologyInventors: Frederick J. Leonberger, Ivars Melngailis, Carl O. Bozler, Robert W. McClelland
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Patent number: 4376285Abstract: An optoelectronic switch has been formed from a semi-insulating substrate of indium phosphide doped with a deep level impurity and disposed intermediate a microstrip transmission line. One conductor of the transmission line has a small gap in its metallization. Upon illumination of the gap by laser pulses which are absorbed near the semiconductor surface, a photogenerated electron-hole plasma forms thereby providing a conducting path across the gap turning the switch "on."A process of fabricating the switch is described, an important feature of which is a heat-treatment process which improves the response time of the switch to .about.50 picoseconds. Another important part of the invention is the formation of an optically semi-transparent metallic film at the gap surface. This provides greater efficiency in the coupling of light into the device at the gap while at the same time maintaining a short electronically non-conductive gap and thus a relatively low ON-state impedance for the switch.Type: GrantFiled: June 23, 1980Date of Patent: March 8, 1983Assignee: Massachusetts Institute of TechnologyInventors: Frederick J. Leonberger, Frederick J. O'Donnell
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Patent number: 4371421Abstract: An improved method and apparatus for crystallizing amorphous or polycrystalline material is disclosed. In this invention, a material which is to be crystallized is formed on a substrate and single crystalline seed material is disposed adjacent and in contact with at least a portion of the material which is to be crystallized. A layer of material which serves as a "wetting agent" is then formed over the material to be crystallized. The structure thus formed is subjected to a heat treatment which melts the material being crystallized and when the material solidifies its crystalline structure is substantially epitaxial based on the seed material. The "wetting agent" layer serves to prevent deleterious balling up of the material during crystallization.Type: GrantFiled: April 16, 1981Date of Patent: February 1, 1983Assignee: Massachusetts Institute of TechnologyInventors: John C. C. Fan, Michael W. Geis, Bor-Yeu Tsaur
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Patent number: 4366338Abstract: A method of compensating grain boundaries or dislocations causing interstices to form particularly in polycrystalline semiconductor materials is disclosed which comprises selectively diffusing opposite impurity-type donor semiconductor material into the interstice to thereby reduce the conductivity of the interstice.Type: GrantFiled: January 9, 1981Date of Patent: December 28, 1982Assignee: Massachusetts Institute of TechnologyInventors: George W. Turner, John C. C. Fan, Jack P. Salerno
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Patent number: 4358146Abstract: A release mechanism which is releasable from the direction of the load and requires that two levers be pulled in sequence and held from the direction of the load for release. Hook-up may be achieved manually with one hand.Type: GrantFiled: February 2, 1981Date of Patent: November 9, 1982Assignee: Massachusetts Institute of TechnologyInventor: Clifford A. Goudey
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Patent number: 4357183Abstract: A method and apparatus is described for producing Ge or a Ge.sub.1-x Si.sub.x heteroepitaxy film on Si by depositing films of Ge or Ge.sub.1-x Si.sub.x on Si and subjecting the body so formed to a controlled temperature environment, wherein the body is rapidly (within a time period t.sub.o of more than about 100 microseconds) brought to a predetermined temperature within the alloy range of the deposited film but less than the melting point of Si. The body is then held at such temperature for a relatively short time not to exceed about 3 minutes, including the time period t.sub.o.Type: GrantFiled: August 13, 1980Date of Patent: November 2, 1982Assignee: Massachusetts Institute of TechnologyInventors: John C. C. Fan, Ronald P. Gale
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Patent number: 4354297Abstract: A fluid power operated fish skinning machine that severs the tail and impales the fish on a wheel. The fish is then rotated past cutting stations where the dorsal fins are removed and the belly flap is cut. The wheel is then stopped opposite a cutting wheel mounted on a drum which is rotatable about its axis in either direction and is pivotable against or away from the fish body. The drum is pivoted against the fish and a transverse slit is made by the cutting wheel in the fish across the backbone near the head of the fish. The drum is then rotated until a gripping device on the drum is disposed in the slit. The gripping device is then pivoted against the drum and grips the skin against the outer surface of the drum. The drum and wheel are then rotated in opposite directions about their axes such that the skin is peeled from the fish.Type: GrantFiled: March 31, 1980Date of Patent: October 19, 1982Assignee: Massachusetts Institute of TechnologyInventors: David G. Wilson, William B. Hoff, III, Roy V. Richard, II