Patent ID: 7897270

Claim:
An organic light emitting diode (OLED) display, comprising: a substrate; a first electrode formed on the substrate; a hole transport layer formed on the first electrode and comprising a first material having a first highest occupied molecular orbital (HOMO) level and a first lowest unoccupied molecular orbital (LUMO) level; a hole blocking layer formed on the hole transport layer and comprising a second material having a second HOMO level and a second LUMO level; an emitting layer formed on the hole blocking layer and comprising a third material having a third HOMO level and a third LUMO level; and a second electrode formed on the emitting layer, wherein the second HOMO level is higher than the first HOMO level and the third HOMO level, wherein the second LUMO level is higher than the first LUMO level and the third LUMO level, and wherein the first material comprises at least one of p-phenylenediamine (PPD), phthalocyanine, copper phthalocyanine (CuPc), Transmembrane Phosphatase with TEnsin homology (TPTE), polyaniline, and polythiophene; the second material comprises at least one of 4,4′-N,N′-dicarbozole-biphenyl (CBP), and aluminum(III) bis(2-methyl-8-quinolinato) 4-phenylphenolate (BAlq); and the third material comprises at least one of anthracene, a distyryl compound, a polyfluorene derivative, a (poly) paraphenylenevinylene derivative, a polyphenylene derivative, a polyvinylcarbazole, and a polythiophene derivative.