The History and Evolution of Traffic Lights

06 29 2020
April Spears

History of Traffic Lights


The traffic lights around today are top of the line. Some of them, like ours, are even solar powered to combine optimal functionality with efficiency. 

Traffic lights are often overlooked, despite the fact that they play an integral role in road safety. Without them, we wouldn’t be able to navigate the roads without the risk of accidents, especially not with the kind of traffic that we have to deal with today. 

Given that nearly 40% of all crashes are estimated to occur at intersections, it’s abundantly clear that without those who put their energy and effort into developing this road safety  technology, things could be far worse. 

In this post, we’re covering the evolution of the often overlooked traffic light and giving some insight into how they helped to pave the way to road safety over time. 

The Early Beginnings of Traffic Lights 

Before we gained access to wide spread electricity, traffic lights and other roadside lighting like street lights were powered by gas and flame… And they were actually around quite a bit before cars came into the picture. They started out as a means to provide signaling of railroad activity to warn and alert those riding on horseback, as well as a way to provide pedestrians with a secure way to cross roads with the increase of horse and buggy traffic. 

These very early traffic lights first took root in London. They were controlled manually by police officers through the use of Semaphore arms during the day, and at night time they relied on gas to illuminate in darkness. 

Up until the 1900s in the United States, police officers primarily manually directed traffic through a combination of using hand signals from towers which allowed them to get a good view of traffic. However, in some areas red and green gas powered lights were used.

The Rise of Electricity

The Rise of Electricity

By the turn of the century, it became clear that a better, more efficient system for monitoring traffic was needed due to the increase of people becoming interested in driving cars rather than relying on horses and trains. 

It was in the year 1912 when the idea of the possibility of having an electric traffic light popped into the head of a police officer. By the time 1914 came around, the first electric traffic light had become a reality and was installed in the city of Cleveland, Ohio. 

The early electric traffic lights contained only red and green colors, and rather than having a yellow light, emitted a loud buzzing sound to alert drivers and pedestrians of the upcoming transition between stop and go. 

Despite being electric rather than gas powered, these early lights still required that someone operate them and manually switch the colors of the lights. 

Automatic Traffic Lights 

By the time the year 1920 rolled around, automatic traffic lights were phasing out the first renditions of the electric lights that were manually operated. The first automatic traffic lights were timed to changed at fixed intervals, but drivers soon realized that this caused quite a bit of unnecessary waiting. 

To remedy this, the lights were fit with microphones that could detect sounds from upcoming traffic, with the noise or lack of noise or lack of noise signaling the change of light color. However, people realized that they could just honk to get the light to change in their favor, and this was dangerous. 

As a solution to the problem, once a light was triggered to change it would not changed again based on traffic sounds for at least another 10 seconds. 

Computerized Detection 

By the mid 1900s, computers had been invented and people saw it as a prime opportunity to take the evolution of the traffic lights even further. Computerized detection was a huge step up from relying on traffic sounds, and allowed for lights to change more efficiently and more reliably. This was not only good for drivers but for traffic pattern monitoring and control during emergency situations. 

From the 1990s Onward 

By the time that we were approaching the year 2000, computers had grown more advanced and allowed for even more features to be included within traffic lights. Most notably, countdown timers, which allowed drivers to better gauge whether or not they would be able to safely make it through a light before turning. 

It’s estimated that nearly 165,000 accidents are caused yearly by people who run red lights, so as simple as count down technology may seem, it was a hugely important step. Without it, who knows how many accidents we would have from light running each year. 

Looking to Upgrade Your Traffic Lights? 

We’re proud to offer a wide range of sustainable, environmentally friendly lighting solutions that combine the best of the technology that we have today with the power of solar energy. With a wide selection of traffic products and lighting solutions, we’re committed to being a part of making roads and intersections safer for both pedestrians and drivers. 

When browsing our selection you'll find everything from pedestrian crossing systems, traffic control systems, time clocks, and more. 

You can learn more about our offerings in the products section, or, just reach out to us directly

We typically respond within two days or less, so you’ll be able to get your project going in no time.