Light degradation sensing LED signal with light pipe collector

摘要

An LED signal with an LED light pipe collector and intelligent light degradation sensor. The light pipe collector captures LED light normally lost in a generally horizontal direction and redirects it into a generally vertical direction through use of total internal reflection. The light degradation sensor monitors LED signal light output. When light output degrades to a preset level, an electrical circuit triggers a disabling short circuit to deactivate the LED signal.