Light-emitting diode into a lower energy level and releases energy in the form of a photon. The wavelength of the light emitted, and thus its color, depends on the band gap energy of the materials forming the "p-n junction". In silicon or germanium diodes, the electrons and holes usually recombine by a "non-radiative transition", which produces no optical emission, because these are indirect band gap materials. The materials used for the LED have a direct band gap with energies corresponding to near-infrared, visible, or near-ultraviolet light. LED development began with infrared and red devices made with gallium arsenide. Advances in materials science
LED display low-power. Displacement of the electromagnetic scan systems included the removal of inductive deflection, electron beam and color convergence circuits and has been a significant achievement. The unique properties of the light emitting diode as an emissive device simplifies matrix scanning complexity and has helped the modern television adapt to digital communications and shrink into its current thin form factor. The 1977 model was monochromatic by design. The efficient Blue LED completing the color triad, did not arrive for another decade. Large displays now use high-brightness diodes to generate a wide spectrum of colors. It took three decades and organic light-emitting