Light-emitting diode superior for illumination in terms of color rendering, whereas one cannot appreciate the color of red or green objects illuminated only by the yellow (and remaining blue) wavelengths from the YAG phosphor. The first white LEDs were expensive and inefficient. However, the light output of LEDs has increased exponentially, with a doubling occurring approximately every 36 months since the 1960s (similar to Moore's law). The latest research and development has been propagated by Japanese manufacturers such as Panasonic, Nichia, etc. and later by Korean and Chinese factories and investment such as: Samsung, Solstice, Kingsun, and countless others. This trend is
Light-emitting electrochemical cell Light-emitting electrochemical cell A light-emitting electrochemical cell (LEC or LEEC) is a solid-state device that generates light from an electric current (electroluminescence). LECs are usually composed of two metal electrodes connected by (e.g. sandwiching) an organic semiconductor containing mobile ions. Aside from the mobile ions, their structure is very similar to that of an organic light-emitting diode (OLED). LECs have most of the advantages of OLEDs, as well as additional ones: There are two distinct types of LECs, those based on inorganic transition metal complexes (iTMC) or light emitting polymers. iTMC devices are often more efficient than their LEP based