The neon signs that we are familiar with begin their lives as tubes of leaded glass. These tubes are heated slowly with blowtorches and bent into patterns, words and pictures. After the tube is bent into the desired shape, an electrode is welded onto the end of the tube, and the entire thing is tightly sealed. A vacuum pump is used to remove all of the air from the glass tube. Although not as easy to assemble as an led sign, the effects of a neon sign are brighter.

Once the air is gone, the pump is reversed, and Neon gas is injected into the glass. Neon is the most commonly used, but it is not the only gas that can be used to create those familiar glowing lights; Argon is another commonly used gas, which creates a bright blue glow instead of Neon’s red. For other shades of reds, yellows, and purples, gases like Helium, Krypton, and Xenon can be used. Using combinations of gases, especially Argon, Murcury, and Phosphorous, there are a total of over 150 colors that can be created.

These gases are all part of the group of elements known as the “noble gases”. They are so-called because of their low reactivity with other elements. This low reactivity makes them well suited for use in lighting, as they will not cause any adverse chemical reactions with the glass or metal in the electrodes.

When the Neon gas has completely filled the glass, an electrical supply is attached to the electrode that seals the tube. The high-voltage electrical current is turned on, and the charge will excite the gas molecules, causing them to glow brightly. These bright signs can even be seen in the daylight.

One of the earliest commercial ventures to use Neon lighting as advertising was a car dealership in Los Angeles, California. The owner purchased two signs that said “Packard”, and they were a huge success. Passers-by stopped to stare, and called the extraordinary lights “liquid fire”.

Today, Neon, much like led signs,  is used all over the country to illuminate and excite people. It’s used for advertising and for works of art. Separate portions of signs are often combined and programmed to turn on and off, which create the illusion of animation.

Las Vegas, Nevada is known as the “Neon Capital of the World”. Other cities, such as Reno, NV and Tokyo, Japan, are also well known for their incredible nighttime displays of Neon lights. Neon signs and neon lights are beautiful works of art, and the science that underlies this beauty is fascinating.