The light emitting diode (LED) signal lights as described below replace flashtube or electric arc type signal lights in applications such as emergency signal lights mounted on motor vehicles.
For years, signal lights (for example, strobe lights) have used flashtube or electric arc type light sources. In recent years, flashtube, electric arc type, and incandescent light sources have been replaced by LED light sources. LED light sources have several advantages over flashtube, electrical arc type, and incandescent light sources. LED light sources are smaller, are more energy efficient, and have a longer cycle life. However, replacing flashtube, electrical arc type, and incandescent light sources with LED light sources presents several challenges.
For example, the dispersal of light emitted from a flashtube light source is wider than an LED light source. LED light sources emit a narrow dispersal of light. In applications such as emergency signal lights, a wide dispersal of light is preferred. Current LED signal lights achieve wide light dispersals by arranging LED light sources to point in different directions away from a central point. However, a large number of LED light sources are required to provide light emission in all directions.
Another advantage of LED light sources is that they produce less heat than flashtube, electric arc type, and incandescent light sources. However, the amount of heat produced by LED light sources is still significant, particularly when a large number of LED light sources are needed. In view of the heat produced by LED light sources, current LED signal lights house their LED light sources on a printed circuit board (PCB) that is physically separated from a PCB which houses the rest of the control electronics. Housing the LED light sources and the control electronics on separate PCBs increases the overall footprint or bulk of the signal light.
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