Materials and architectures for efficient harvesting of singlet and triplet excitons for white light emitting OLEDs
First Claim
Patent Images
1. An organic light emitting device comprising:
- a cathode,an emissive region, andan anodewherein,the emissive region consists of;
a fluorescent layer comprising a fluorescent emitting dopant, and a charge-transporting dopant in a host material,one or more phosphorescent layers, each comprising a phosphorescent emitting dopant, and a charge-transporting dopant in a host material, andan optional spacer layer between the fluorescent layer and a phosphorescent layer comprising a charge-transporting dopant in a host material,wherein the host material for the fluorescent layer, the host material for the phosphorescent layers and the host material for the spacer layer, if present, are the same material; and
wherein the charge-transporting dopant is a hole-transporting dopant or the charge-transporting dopant is an electron-transporting dopant, wherein if the charge-transporting dopant is a hole-transporting dopant, the HOMO level of the hole-transporting dopant is above and closer to the vacuum energy level than the HOMO level of the fluorescent emitting dopant and the HOMO level of the phosphorescent emitting dopant or if the charge-transporting dopant is an electron-transporting dopant, the LUMO level of the electron-transporting dopant is below the LUMO level of the fluorescent emitting dopant and the LUMO level of the phosphorescent emitting dopant, and wherein the triplet energy of the charge-transporting dopant is higher than the triplet energy of the host material.
3 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates to organic light emitting devices (OLEDs), and more specifically to OLEDS that emit light using a combination of fluorescent emitters and phosphorescent emitters for the efficient utilization of all of the electrically generated excitons.
47 Citations
13 Claims
-
1. An organic light emitting device comprising:
-
a cathode, an emissive region, and an anode wherein, the emissive region consists of; a fluorescent layer comprising a fluorescent emitting dopant, and a charge-transporting dopant in a host material, one or more phosphorescent layers, each comprising a phosphorescent emitting dopant, and a charge-transporting dopant in a host material, and an optional spacer layer between the fluorescent layer and a phosphorescent layer comprising a charge-transporting dopant in a host material, wherein the host material for the fluorescent layer, the host material for the phosphorescent layers and the host material for the spacer layer, if present, are the same material; and wherein the charge-transporting dopant is a hole-transporting dopant or the charge-transporting dopant is an electron-transporting dopant, wherein if the charge-transporting dopant is a hole-transporting dopant, the HOMO level of the hole-transporting dopant is above and closer to the vacuum energy level than the HOMO level of the fluorescent emitting dopant and the HOMO level of the phosphorescent emitting dopant or if the charge-transporting dopant is an electron-transporting dopant, the LUMO level of the electron-transporting dopant is below the LUMO level of the fluorescent emitting dopant and the LUMO level of the phosphorescent emitting dopant, and wherein the triplet energy of the charge-transporting dopant is higher than the triplet energy of the host material. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An organic light emitting device comprising:
-
a cathode, an emissive region, and an anode wherein the emissive region consists of; a fluorescent layer comprising a first fluorescent emitting dopant and a hole-transporting dopant in a host material, a phosphorescent-sensitized fluorescent layer comprising a phosphorescent emitting dopant, a second fluorescent emitting dopant, and a hole-transporting dopant in a host material, and an optional spacer layer between the fluorescent layer and a phosphorescent layer comprising a charge-transporting dopant in a host material; and wherein the host material for the fluorescent layer, the host material for the phosphorescent-sensitized fluorescent layer and the host material for the space layer, if present, are the same material, wherein the HOMO level of the hole-transporting dopant is above and closer to the vacuum energy level than the HOMO level of the fluorescent emitting dopant and HOMO level of the phosphorescent emitting dopant, and wherein the triplet energy of the hole-transporting dopant is higher than the triplet energy of the host material. - View Dependent Claims (11, 12, 13)
-
Specification