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The 20th anniversary of Japan’s first LED traffic light – Tokushima City

 The first traffic light equipped with blue LEDs (light-emitting diodes) in Japan was installed in Tokushima City in 1994 at the crossing in front of the headquarters of the Tokushima Prefectural Police.
 In 1993, the prefectural police requested Nichia Corporation (in Anan City) to develop a traffic light using blue LEDs. The blue LED was invented by Shuji Nakamura while he was working for the company. Nakamura, a graduate of the University of Tokushima, is this year’s Nobel Prize winner in Physics, and a professor at the College of Engineering, University of California at Santa Barbara. Through trial and error, the traffic light finally came into use on October 21, 1994, ahead of any other prefecture.
 Incandescent light bulbs then in general use had problems, including its colors becoming hard to recognize when reflecting the glow of the morning or evening sun. LED lamps, on the other hand, emit light in three colors by themselves; their colors are hence easier to distinguish for drivers and pedestrians.
 The LED traffic light has been working for 20 years since its installation without replacing any of its lamps even once. LED lamps became diffused nationwide afterward since LEDs are highly durable, enabling a significant reduction of electricity consumption.
 Tokushima Prefecture started the “LED-valley Project” in 2005, with the aim of promoting lighting industries related to LEDs, the light source of the 21st century. Since then, the number of companies engaged in LED-related production has increased from 10 to 123. In Tokushima, LEDs are now essential for promoting local industries and communities.
 
 
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Plaque commemorating the 20th anniversary of Japan’s first LED traffic light
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Contact : Traffic Control Section, Traffic Department, Headquarters of Tokushima Prefectural Police
Phone or E-mail +81-88-622-3101
Website http://www.police.pref.tokushima.jp/