This book presents topical research in the field of light-emitting diodes and the systems, uses and efficiency of optoelectronics. Topics discussed include fabricating high efficiency organic light-emitting diodes for flat panel displays and solid-state lighting; reliability estimation from the junction to the packaging of LED; next-generation intelligent and green energy LED backlighting 3D display; inorganic-organic hybrid emitting material fabricated by solvothermal synthesis and photonic bandgap defect structure based on IV-VI semiconductors.