Why are street lights purple
street lights across cities around the world have been turning purple, and this is due to a manufacturing error caused by outsourced third-party vendors in Asia. Specifically, the problem is due to the packaging that surrounds the LED street lights. Generally, LEDs have been the hot new thing for the past few years because they don't get hot.
Red and green LEDs have existed since the middle of the 20th century, and when companies needed to make white light, companies like Acuity no longer actually needed the red and green ones. This caused a manufacturing error in the phosphor coating delaminating from the LEDs, resulting in the street lights being purple. This manufacturing error and the vagaries of the global supply chain has caused this problem.
Many cities have bought their LED lights from Acuity, and the purple lights are a result of this manufacturer error.
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