Application of high brightness LED railway handheld signal lights

Traditional incandescent light bulb railway handheld signal lights are easy to damage, inconvenient to repair, and traffic accidents occur frequently. However, light emitting diodes ( LEDs ) have the advantages of long service life, good reliability, shock resistance, and not easy to damage. Using these characteristics of LEDs, a new type of light source has been developed to replace incandescent bulbs.

LED is a kind of electroluminescent light source. Its light-emitting principle is that when a forward voltage is applied to both ends of the PN junction, the holes in the P region will flow to the N region; and the electrons in the N region will flow to the P region. As the minority carriers and majority carriers recombine to release energy, part of the energy is converted into heat, and the other part of the energy is converted into light. The color of LED light is determined by the matrix and the doped materials. Except for white light, it is basically a relatively pure monochromatic light. The light color is easy to control, so it can be widely used in various LED traffic lights , LED hand signal lights, LED screens, etc.

Traditional railway handheld signal lights generally use ordinary incandescent bulbs or gas-filled incandescent bulbs as light sources, and produce corresponding red signals, green signals, and yellow signals through red, green, and yellow polycarbonate color filters. On the one hand, it is difficult to accurately control the amount of color powder added during the polycarbonate processing and molding process, resulting in impure signal colors. On the other hand, after long-term use, polycarbonate will gradually turn yellow, especially under sunlight, affecting the color of the signal.

Moreover, the life of incandescent bulbs is only a dozen hours, and they need to be replaced frequently. The continuous working time cannot reach the required 10 hours or more. The lamps are also heavy and inconvenient to carry. Currently, many manufacturers have adopted red, green, and yellow LEDs as signal light sources, and some manufacturers have adopted multiple ultra-bright white LEDs as white light sources, which can fully meet the application requirements of handheld signal lights.