The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 07, 2008
Filed:
Oct. 20, 2003
Norbert Fruehauf, Sindelfingen, DE;
Norbert Fruehauf, Sindelfingen, DE;
Universitaet Stuttgart, Stuttgart, DE;
Abstract
A driving circuit for an image point of an image screen which has an organic light-emitting diode includes a capacitor, a feedback coupling, a first thin film transistor as a current-driving transistor for the diode, a second transistor which is connected by a current-conducting electrode with a gate of the first transistor and by a second current-conducting electrode with a data conductor and by its gate electrode with a scanning signal conductor, a third thin film transistor which during driving its gate through a driving conductor taps a diode driving current and an output of the first transistor and supplies a current measuring- and voltage regulating circuit, the current measuring- and voltage regulating circuit providing to the data conductor a voltage signal which is dependent on a current measuring result and a voltage comparison, so that the diode during driving of the gate of the third transistor due to its non-linear switching characteristic acts as a switch for a current deviation in the current measuring- and voltage regulating circuit.