Abstract: As the time pass in this modern world many changes came into the field of display devices. First came the small LED (Light Emitting Diode) display which shows numeric contain then after jumbo CRT (cathode ray tubes) which is used today also but due bulkiness we do not carry from one place to another and also required large area. Then after came LCD (Liquid crystal display) which is lighter and easy to carry, but the main problem with LCD is that it cannot seen clear picture from different angles. This all problem will be overcome by revolutionary discovery of OLED (Organic Light Emitting Diode).