We prepared two kinds of OLED devices by spin coating, which have three-layer structures[a:ITO/MEH-PPV/Al] and [b: ITO/MEH-PPV/Ca:Al].是什么意思_We prepared two kinds of OLED devices by spin coating, which have three-layer structures[a:ITO/MEH-PPV/Al] and [b: ITO/MEH-PPV/Ca:Al].在线翻译_英语_读音_用法_例句