Patent ID: 7385481

Claim:
A signaling control device apparatus comprising: a light source including at least one LED, the light source having a light emitting surface; at least one sensor set to detect an external light load directed to the light emitting surface and generate a control signal indicative of a presence of the external light load, the external light load being one of sunlight and a light from approaching train headlights; and an electrical control system for receiving the control signal indicative of the presence of the external light load and triggering an increase in current being supplied to the at least one LED in response to the received control signal which increased current is being maintained for at least while the external light load is present; wherein the at least one LED and the at least one sensor are disposed on a same printed circuit board; and wherein the current is raised by pulsing the current to cause the at least one LED to pulse at a frequency higher than visually perceivable.