Patents by Inventor Janos Hajto

Janos Hajto has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7260297
    Abstract: The present invention describes a fluorescent dye doped polymer based optical wave-guide structure. The described polymers can be used to fabricate a range of display elements and illumination systems which work without the use of external electrical power. This is due to the process of the fluorescent dyes absorbing ambient light and then subsequently emitting light which is conducted by the polymer host material to a point where it is emitted. The emitted light can be of a range of colours depending upon the type of dye that polymers are doped with. There is a constant contrast between the light power flux emitted for the wave-guide structure and the light power flux of the ambient light. There is also provided a method in which a dielectric stack mirror layer fabricated on the surface of the polymer which can be used to improve the efficiency and the contrast of those optical elements.
    Type: Grant
    Filed: December 16, 2004
    Date of Patent: August 21, 2007
    Assignee: The Court of Napier University
    Inventors: Janos Hajto, Colin Hindle, Andrew Graham
  • Publication number: 20050179366
    Abstract: A field emission device having improved properties and which finds use in display devices, such as a flat panel displays. Known devices and displays suffer from problems such as complexity of fabrication and limited color gamut. The present device provides a field emission backplate which is made from a substantially semiconductor based material and has a plurality of grown tips. The device also includes at least one electro-luminescent or photo-luminescent material having a fluorescent material such as a fluorescent dye doped material chemically attached thereto.
    Type: Application
    Filed: December 17, 2004
    Publication date: August 18, 2005
    Inventors: Mervyn Rose, Ravi Silva, John Shannon, Janos Hajto
  • Publication number: 20050111813
    Abstract: The present invention describes a fluorescent dye doped polymer based optical wave-guide structure. The described polymers can be used to fabricate a range of display elements and illumination systems which work without the use of external electrical power. This is due to the process of the fluorescent dyes absorbing ambient light and then subsequently emitting light which is conducted by the polymer host material to a point where it is emitted. The emitted light can be of a range of colours depending upon the type of dye that polymers are doped with. There is a constant contrast between the light power flux emitted for the wave-guide structure and the light power flux of the ambient light. There is also provided a method in which a dielectric stack mirror layer fabricated on the surface of the polymer which can be used to improve the efficiency and the contrast of those optical elements.
    Type: Application
    Filed: December 16, 2004
    Publication date: May 26, 2005
    Inventors: Janos Hajto, Colin Hindle, Andrew Graham
  • Patent number: 5541869
    Abstract: The resistance of a resistive memory element, e.g. a synaptic element is programmed, e.g. adjusted to a target value, by pulses of a constant height and variable width. One polarity gives an increase in resistance; the other polarity gives a decrease. A short pulse applied after a longer pulse appears to have no effect. After each polarity change short pulses can again be used to make small adjustments. In a preferred embodiment longer and longer pulses are used until the resistance overshoots the target value. After overshooting the polarity is reversed and a second series of pulses is used to obtain a closer approach to the target. The resistive element comprises a resistive layer located between two electrodes, e.g. a matrix of amorphous silicon doped with boron containing V. One electrode is Cr and the other is V.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: July 30, 1996
    Assignee: British Telecommunications, plc
    Inventors: Mervyn J. Rose, Janos Hajto, Alan E. Owen, Ian S. Osborne, Anthony J. Snell, Peter G. Le Comber, deceased
  • Patent number: 5360981
    Abstract: An analogue memory device comprises a layer of doped amorphous silicon located between a first conducting layer metal contact layer of V, Co, Ni, Pd, Fe or Mn. It has been found that the selection of one of these metals as the contact exerts a significant effect on the properties of the device, e.g. the selection of Al, Au or Cu gives no switching whereas Cr, W, Ag give digital instead of analogue switching.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: November 1, 1994
    Assignee: British Telecommunications public limited company
    Inventors: Alan E. Owen, Anthony J. Snell, Janos Hajto, Peter G. Lecomber, Mervyn J. Rose