{HEAD ~ The infrared light emitting device} 12, wherein {TAIL ~ the p type} doped compound semiconductor protection layer has the same composition as any one of the first n type compound semiconductor layer and the π layer 
wherein
{ HEAD ~ The infrared light emitting device } 12 , wherein { TAIL ~ the p type } doped compound semiconductor protection layer has the same composition as any one of the first n type compound semiconductor layer and the π layer
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH