Abstract: Systems and methods of controlling traffic including a traffic signal. The traffic signal including one or more lamps configured to each display a plurality of patterns by selectively powering different groups of bulbs. Embodiments of the invention include lamps configured to alternatively display an arrow pattern, a filled circle pattern, a bar pattern or other pattern meaningful to traffic control. The pattern displayed is optionally dependant on available power sources, ambient light, traffic flow, time of day or day of week. Embodiments of the invention include a bulb assembly including different groups of bulbs and configured to be controlled using as few as two hot electrical inputs.

Abstract: A traffic priority defining system implemented by emergency vehicles at an intersection. A signal, designated the second electronic signal, post emanation, is electronically verified as to source and sent to the controller for a traffic control device, such as a tricolor traffic light, to override the primary signal operating the traffic light for opposing traffic. One of the colored lights, usually yellow, is actuated to a second operational mode, to display an icon of an emergency situation. The specified color light's incandescent bulb resumes normal full to yield a yellow glow at the proper time.