  :There is a basic difference between LED and OLED technology. LEDs are made from anorganic, monolithic semiconductor wafers comparable to most of the chips used in electronics. Individual LEDs are cut from such wafern and then contacted by wire bonding or other contacting methods used for chips. In order to build an LED display, sets of RGB LEDs are mounted together by hybrid technology to obtain individual pixels. Due to this mounting technique, the distance between the centers of neighboring pixels is rarely smaller than 1 mm. Therefore, such LED displays are normally used for large-screen applications such as electronic billboards, where the resolution is sufficent for viewing at a distance.  :In contrast, OLEDs are made with organic materials deposited with thin-film technology on a large substrate. The substrates have the full dimensions of the display. The individual diodes, driving electronics and interconnections are made comparable to the internal structure of an integrated circuit (chip), allowing a much denser pixel arrangement as required by high-resolution small displays in smartphones etc.  