Organic electroluminescent device including charge transport buffer layer
US6614176B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2001 |
| Grant date | Sep 2, 2003 |
| Priority date | — |
| Expiry date | Jun 3, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/917
Abstract
An organic electroluminescent device includes a substrate, and an anode, a hole transport layer, a plurality of light emitting layers, an electron transport layer and a cathode in sequence laminated on the substrate, and a charge transport buffer layer. The charge transport buffer layer adjusts the proportion of excitons generated by two light emitting layers by adjusting a film thickness, and is formed between the light emitting layers. In the organic electroluminescent device, excitons are formed directly on a separate emission region, rather than at the interface between the hole transport layer and the light emitting layers, by forming the charge transport buffer layer between light emitting layers. As a result, lowering of the luminous efficiency is prevented at the interface due to formation of an exciplex. Further, the luminescence ratio of a dichromatic luminous region is adjusted by adjusting the thickness of the charge transport buffer layer, thus easily attaining color tuning.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.