Light-emitting device and organic electroluminescence light-emitting device
US8704253B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 2004 |
| Grant date | Apr 22, 2014 |
| Priority date | — |
| Expiry date | Sep 4, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10K85/6565
Abstract
In conventional organic EL light-emitting devices, the ITO used for a transparent electrode has a refractive index of about 2.0 larger than the refractive index of 1.5 of a transparent glass substrate. As a result, the mode of most of light traveling from the transparent electrode toward the glass substrate is the transparent electrode guided mode, and no light is emitted from the transparent electrode toward the glass substrate. According to the invention, the light extraction efficiency of conventional light-emitting devices such as organic EL light-emitting devices is improved by using mode conversion means so as to solve the problem that conventional light-emitting devices such as organic EL light-emitting devices have low light extraction efficiencies. A light-emitting device of the invention comprises a light-emitting layer on a substrate and mode conversion means for converting the mode from the guided mode into an emission mode. The mode conversion means is provided in the substrate, in the light-emitting layer, or at the interface between the substrate and the light-emitting layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.