An organic light emitting device having an anode, {TAIL ~ a cathode} and an organic layer between the anode and {HEAD ~ the cathode} is provided 
An organic light emitting device having an anode , { TAIL ~ a cathode } and an organic layer between the anode and { HEAD ~ the cathode } is provided
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH