Tandem OLEDs having low drive voltage

US7075231B1 · kind B1 · utility

Assignee

• EASTMAN KODAK COMPANY · US

Inventors

• Liang-Sheng Liao · Rochester, US
• Tukaram K. Hatwar · Penfield, US
• Kevin P. Klubek · Webster, US
• J. Ramon Vargas · Webster, US
• Dustin L. Comfort · Webster, US

Key dates

• Filing date: Jan 3, 2005
• Grant date: Jul 11, 2006
• Expiry date: Jan 3, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10K2102/351

Abstract

A tandem OLED includes an anode, a cathode, and at least two electroluminescent units disposed between the anode and the cathode, wherein each of the electroluminescent units includes at least one hole-injecting layer, one hole-transporting layer, one organic light-emitting layer, one electron-transporting layer, and one electron-injecting layer. The OLED also includes at least one intermediate connector, wherein each of the intermediate connectors includes at least one layer, and wherein each of the intermediate connectors is disposed between electroluminescent units, wherein the thickness of each layer in each of the electroluminescent units and the intermediate connectors is selected to satisfy the test condition that the voltage drop from the anode to the cathode is less than 4.0 V×N (the number of electroluminescent units) at 20 mA/cm2.