Traffic Control System

Traffic signal lights

Incandescent bulbs used to be the light source, but in recent years, light-emitting diodes (LEDs) have been replacing them nationwide.
Compared to incandescent bulbs, LEDs have features such as improved visibility by preventing the “pseudo-lighting phenomenon” that makes it appear as if the light is on when the sun is shining in the west, energy saving (approximately 1/6), and long life (approximately 6-8 years).

Traffic signals lights for vehicles

The diameter of the lens must be between 20 and 45 cm according to the Road Traffic Law Enforcement Regulations, with 25 cm being the most common in recent years.
The hood to protect the lights from sunlight was essential in the days when incandescent bulbs were used as light sources, but as incandescent bulbs have been replaced by LED light sources, traffic lights without a hood have become common.

Pedestrian signal lights (with the elapsed time indicator)

The lens is square, and according to the Enforcement Regulations of the Road Traffic Law, the size of the lens is between 20 and 25 cm, with 25 cm being the most common size.
When incandescent bulbs were used as the light source, the doll was white (bulb color) and the surrounding area was red or blue (green). The light source is now LED and only the doll part emits red or blue (green) light, and the design of the doll has also been changed.
The elapsed time indicator has also been integrated with the pedestrian signal lights.