Because of the rich color performance and excellent resolution of TFT LCD, this display technology is very suitable for close viewing distance with human eyes, so TFT LCD is widely used in public information signboards (PID) or digital signage board for public or commercial use. Basically, for both PID or digital signage applications, can be located in indoors or semi outdoors environments, such as airports, department stores, and hypermarkets, sometimes, it also can be requested to install in shopping areas, sightseeing areas, street sides or various outdoor and semi-outdoor locations. Therefore, there are many rigorous considerations for specification requirements.