Based on the 2-diphenylamino-7-(2,2-diphenylvinyl)-9,9′-spirobifluorene(DPV) as emitter layer,high efficient blue organic light-emitting diodes(OLEDs) with a typical structure of ITO/m-MTDATA(30 nm)/NPB(20 nm)/DPV(d nm)/BCP(10 nm)/Alq3(30 nm)/LiF(1 nm)/Al(100 nm) were fabricated via the thermal vacuum deposition method.By adjusting the thickness of the DPV layer,the electroluminescent(EL) characteristics of the devices were investigated.The test results indicate that the maximum luminous efficie...