Is the revolution running in lighting? Indeed, the lighting domain is facing a unique technology breakthrough with the emergence of new kinds of devices and luminaries based on semiconductor chips, so-called Light-Emitting-diodes or LEDs. In the beginning, the low power and fluxes of LED lighting impeded them from being used for lighting and kept them confined to indicator applications. However, the invention of the blue LED in the middle of the 1980s gave access to white light combining red, green and blue LEDs or by means of partial photo conversion of blue light to yellow light using phosphors. White LEDs in their turn have made electronic lighting accessible, opening new business opportunities to companies. Consequently, labs and companies have focused their efforts on increasing LED lighting efficiencies and fluxes. All these efforts have already led to significant results.
LED lighting is a recent phenomenon, but LED deployment in this field of application now seems inevitable. The LEDs have become a credible alternative to incandescent lamps, soon to be banned because of their energy inefficiency. The multiple benefits of LED lighting and the continuous increase in their performance allied to the decrease of their manufacturing costs are likely to make them competitive when compared to fluorescent lamps and tubes. Will 2009 mark the true take-off of LED lighting? We do not know yet, but in any case High Brightness white LEDs have become a reality and it is the objective of this book to give to its readers a wide scientific and technological overview of what they are, including all LED manufacturing steps, aspects related to their photoelectric characterization up to characteristics of the light they produce. It also offers opportunities to organic LEDs.
