Abstract Blue electroluminescence was observed form single layer polymer OTFEL devices.The device has a structure of glass substrate/ITO/ethetting layer/Mg:Ag electrode.Perylene doped poly (9-vinylcarbazole) was used as an emitting layer. The film was fabricated by spin coated method with chloroform solution. The excitation and emission spectra of perylene. PVCz and perylene doped PVCz thin films has been measured. The PL spectrum of perylene doped PVCz is that of perylene

but the excitation spectra is the same of PVCz. This shows that energy transition take place between PVCz and perylene. The emission spectra of EL cell is the same as that of PL emission spectrum of perylene. thus perylene molecular are the mian emitters. The I-V and B-V characteristic were measured. It is found that they have a good rectify property

a brightness of 59 cd/m

2

is observed at 12V dc.