Voltage programmed pixel circuit, display system and driving method thereof
AssigneeIgnis Innovation Inc.
InventorsArokia Nathan, Gholamreza Chaji, Peyman Servati
Life of this patent
Estimating the term…
Abstract
A voltage programmed pixel circuit, display system having the pixel circuit and driving method thereof is provided. The pixel circuit includes a light emitting device, a driving transistor connected to the light emitting device and a programming circuit. The programming circuit adjusts a pixel current during a programming cycle of the pixel circuit.
Claims28
A pixel circuit comprising:
- a light emitting device having a first electrode and a second electrode;
- a driving transistor having a gate terminal, a first terminal and a second terminal, the first terminal of the driving transistor being connected to the first electrode of the light emitting device;
- a first capacitor having first and second terminals, the first terminal of the first capacitor being connected to the gate terminal of the driving transistor, the second terminal of the first capacitor being connected to the first terminal of the driving transistor and the first electrode of the light emitting device;
- a first switch transistor having a gate terminal, a first terminal and a second terminal, the first terminal of the first switch transistor being connected the gate terminal of the driving transistor and the first terminal of the first capacitor;
- and
- a programming circuit for locally adjusting a pixel current during the programming cycle of the pixel circuit, the programming circuit having a programming transistor, the programming transistor being connected to the first electrode of the light emitting device and being biased during the programming cycle of the pixel circuit.
A method of driving a pixel circuit, the pixel circuit comprising a light emitting device having a first electrode and a second electrode;
- a driving transistor having a gate terminal, a first terminal and a second terminal, the first terminal of the driving transistor being connected to the first electrode of the light emitting device;
- a first capacitor having first and second terminals, the first terminal of the first capacitor being connected to the gate terminal of the driving transistor, the second terminal of the first capacitor being connected to the first terminal of the driving transistor and the first electrode of the light emitting device;
- a first switch transistor having a gate terminal, a first terminal and a second terminal, the first terminal of the first switch transistor being connected the gate terminal of the driving transistor and the first terminal of the first capacitor;
- and a programming circuit having a programming transistor, the programming transistor being connected to the first electrode of the light emitting device;
- the method comprising the steps:
- at a programming cycle of the pixel circuit, biasing the programming transistor to locally adjust a pixel current;
- at a driving cycle of the pixel circuit, enabling the programming transistor to be off.
A pixel circuit incorporating a short term biasing condition in which a programming TFT is stable.
A pixel circuit structure comprising two distinct parts having one programming part and one driving part, in which the programming part is under stress for a small fraction of frame time and adjusting the pixel current, while the driving part drives an OLED.
Dependencies are inferred from the claim text.