Most lighting designers believe that all LED products are of the same quality, and only a few of these manufacturers can produce high-quality leds.Low quality leds are sufficient for simple indication applications.But high quality leds must be used in many areas that require consistency, reliability, solid state indication or lighting, especially in harsh environments such as highways, military/aviation, and industrial applications. In New York subway station and other environments, safety requirements are very demanding, LED must meet the fundamental factors of high quality requi...