The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 01, 2003
Filed:
May. 22, 2001
Rung-Ywan Tsai, Tao-Yuan Hsien, TW;
Chia-Shy Chang, Hsinchu, TW;
Ching-Ian Chao, Hsinchu, TW;
Mu-Yi Hua, Miao-Li Hsien, TW;
Industrial Technology Research Institute, Hsinchu, TW;
Abstract
The present invention relates to an organic light-emitting device which provides an electroluminescence (EL) or photoluminescence (PL) device with high external quantum efficiency. The present invention forms a composite film layer with continuously changing refraction indices between an ITO transparent electrode and a substrate made of plastic or glass. The refraction index of the composite film layer is the same as the ITO electrode at the interface with the ITO electrode. It decreases along the direction perpendicular to the substrate in a linear or nonlinear way. The refraction index is the same as that of the plastic or glass at the interface with the substrate. This way can avoid reflection due to the difference in the refraction index across the interface. The excited light originally trapped in the ITO electrode can be guided outwards. A preferred mean is to incorporate a photon wave guide formed at the interface between the substrate and the air to increase the external quantum efficiency of this type of organic light-emitting devices.