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:
May. 29, 2018
Filed:
Sep. 22, 2011
Denis Sarrasin, Sassenage, FR;
Denis Sarrasin, Sassenage, FR;
Abstract
An active matrix light-emitting diode display screens, and in particular those with organic diodes is discussed. The display screen includes an active matrix of pixels, each pixel including a light-emitting diode, a control MOS transistor for applying a variable voltage or current to the anode of the diode, a selection transistor for applying a variable analog voltage representing a relative level of luminance of the pixel in the image, to the gate of the transistor, during a write phase of this pixel, a storage capacitor for maintaining this voltage on the gate of the transistor outside the write phase. A mean luminance attenuation circuit including a switch for periodically connecting one of the electrodes of the diode, preferably the cathode, to one or other of two fixed potentials, and a switch control circuit for switching with a variable duty cycle according to the desired attenuation.