Patents by Inventor Leo Karl

Leo Karl 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).

  • Doped semiconductor material and process for production thereof
    Patent number: 7858967
    Abstract: The invention relates to a doped organic semiconductor material with increased charge carrier density and more effective charge carrier mobility, which may be obtained by doping an organic semiconductor material with a chemical compound comprising one or several organic molecular groups (A) and at least one further compound partner (B). The desired doping effect is achieved after cleavage of at least one organic molecular group (A) from the chemical compound by means of at least one organic molecular group (A) or by means of the product of a reaction of at least one molecular group (A) with another atom or molecule.
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: December 28, 2010
    Assignee: Novaled AG
    Inventors: Martin Pfeiffer, Leo Karl, Ansgar Werner, Torsten Fritz
  • Protective circuit for a network-controlled thyristor bridge
    Patent number: 6903911
    Abstract: A protective circuit (SCH) for a line-commutated thyristor bridge (B, B?), which is designed for feeding energy of a power circuit connected to the bridge and also for feedback from this circuit, and which is connected between the thyristor bridge and the power circuit. In a series branch of the protective circuit, there is at least one IGBT transistor (GT1, GT2), which is biased in the feedback direction with an inverse-parallel diode (D1, D2; D1p), and which can be deactivated for the appearance of a tipping recognition signal (sk, Us1), which is supplied by a control circuit (AST) associated with the transistor.
    Type: Grant
    Filed: July 5, 2001
    Date of Patent: June 7, 2005
    Assignee: Siemens AG Osterreich
    Inventors: Wilhelm Reischer, Leo Karl, Heinz Pichorner, Franz Wöhrer
  • Doped organic semiconductor material and method for production thereof
    Publication number: 20050040390
    Abstract: The invention relates to a doped organic semiconductor material with increased charge carrier density and more effective charge carrier mobility, which may be obtained by doping an organic semiconductor material with a chemical compound comprising one or several organic molecular groups (A) and at least one further compound partner (B). The desired doping effect is achieved after cleavage of at least one organic molecular group (A) from the chemical compound by means of at least one organic molecular group (A) or by means of the product of a reaction of at least one molecular group (A) with another atom or molecule.
    Type: Application
    Filed: February 20, 2003
    Publication date: February 24, 2005
    Inventors: Martin Pfeiffer, Leo Karl, Ansgar Werner, Torsten Fritz
  • Protective circuit for a network-controlled thyristor bridge
    Publication number: 20030160286
    Abstract: A protective circuit (SCH) for a line-commutated thyristor bridge (B, B′), which is designed for feeding energy of a power circuit connected to the bridge and also for feedback from this circuit, and which is connected between the thyristor bridge and the power circuit. In a series branch of the protective circuit, there is at least one IGBT transistor (GT1, GT2), which is biased in the feedback direction with an inverse-parallel diode (D1, D2; D1p), and which can be deactivated for the appearance of a tipping recognition signal (sk, Us1), which is supplied by a control circuit (AST) associated with the transistor.
    Type: Application
    Filed: March 12, 2003
    Publication date: August 28, 2003
    Inventors: Wilhelm Reischer, Leo Karl, Heinz Pichorner, Franz Wohrer