Organic light emitting diode display

• US 20120043894A1
• Filed: 05/06/2011
• Published: 02/23/2012
• Est. Priority Date: 08/19/2010
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Koh, Byung-Sik
• Granted Patent: US 8,531,099 B2
• Time in Patent Office: Days
• US Class Current: 315/151
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than one capacitor
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: H10K 59/13 comprising photosensors that control luminance

Abstract

An organic light emitting diode (OLED) display includes a substrate, an organic light emitting element including a first electrode, an organic emission layer, and a second electrode on the substrate, a driving thin film transistor turning on/off first power supplied to the first electrode and including a first active layer including zinc oxide (ZnO), a photo sensor disposed between the substrate and the organic emission layer and including a second active layer sensing light emitted from the organic emission layer, and a controller controlling at least one of the first power and a second power supplied to the second electrode according to the intensity of the light sensed by the photo sensor.

Claims

1. An organic light emitting diode (OLED) display comprising:

a substrate;

an organic light emitting element including a first electrode, an organic emission layer, and a second electrode on the substrate;

a driving thin film transistor that turns on/off first power supplied to the first electrode, and including a first active layer including zinc oxide (ZnO);

a photo sensor disposed between the substrate and the organic emission layer, and including a second active layer that senses light emitted from the organic emission layer; and

a controller controlling at least one of the first power and a second power supplied to the second electrode according to an intensity of light sensed by the photo sensor.

2. The OLED display as claimed in claim 1, wherein the second active layer includes amorphous silicon.

3. The OLED display as claimed in claim 2, further comprising a switching thin film transistor that turns on a third power that controls the driving thin film transistor and including a third active layer.

4. The OLED display as claimed in claim 3, wherein the third active layer includes the same material as the first active layer.

5. The OLED display as claimed in claim 3, wherein the third active layer includes the same material as the second active layer.

6. The OLED display as claimed in claim 1, wherein the photo sensor further comprises a sensor input end and a sensor output end contacting respective ends of the second active layer, and wherein a sensing thin film transistor is connected with the sensor input end.

7. The OLED display as claimed in claim 1, further comprising a light blocking layer disposed between the second active layer and the substrate.

8. The OLED display as claimed in claim 7, wherein the light blocking layer contacts the second active layer.

9. The OLED display as claimed in claim 7, wherein the light blocking layer comprises at least one of titanium nitride (TiN_x) and aluminum nitride (AlN_x).