The History of Neon Signs
The theory behind neon sign technology is rooted in 1675, long before electricity was invented. Jean Picard*, a French astronomer, noticed a faint glow inside a mercury barometer tube. The tube became brighter when it was shaken. However, the reason for the glow (static electricity), was not known at the time.
Although the causes of barometric lighting were not fully understood, they were investigated. After the principles of electricity were established, scientists were able move forward to the creation of various forms of lighting.
Electric Discharge Lamps
The Geissler tube, named after Heinrich Geissler (German glassblower, physicist) was created in 1855. After electric generators were created, many inventors started to experiment with Geissler tubes and other gases. The gas will glow when placed under low pressure.
After years of experimentation, many types of electric discharge lamps and vapor lamps were developed in Europe and America by 1900. The electric discharge lamp, which is simply a light source consisting of a transparent container in which a gas is energized using an applied voltage, is defined as a device that glows when it is lit.
Georges Claude – Inventor and Inventor of The First Neon Lamp
Neon is a Greek word that means “the new gas.” William Ramsey and M. W. Travers discovered neon gas in London in 1898. The rare gaseous element Neon can be found in the atmosphere in a small amount of 65,000. It is made by the liquefaction and fractional distillation of air.
Georges Claude, a French engineer, chemist and inventor, was born Sept. 24, 1870. He died May 23, 1960. Georges Claude presented the first neon lamp in Paris on December 11, 1910.
Georges Claude patented a neon lighting tube in January 1915 – U.S. patent 1,125,476
Georges Claude and Claude Neon, a French company, introduced neon gas signs in the United States. They sold two signs to a Packard car dealer in Los Angeles. Earle C. Anthony bought the signs that read “Packard” at $24,000.
Outdoor advertising quickly adopted neon lighting as a standard. People would stop to stare at neon signs even when they were not lit up, and the first ones were dubbed “liquid flame”.
Make a neon sign
For neon lamps, hollow glass tubes are available in lengths of 4, 5, and 8 feet. The glass is heated with forced air and lit gas to form the tubes. There are many types of glass depending on where they come from. Soft glass can be composed of lead glass, soda-lime and barium glasses. Also, “Hard” glass from the borosilicate group is used. The glass’s working temperature range is dependent on its composition. It can be as low as 1600°F to as high at 2200°F. Propane gas has a temperature of 3000°F.
The tubes are cut (partial cut), while they are still cold. They then get snapped apart when hot. Next, the artisan creates curve and angle combinations. The tube must then be processed after it is completed. The process will vary depending on where you live. In the USA, this is known as “bombarding”. The tube is then partially evacuated from air. Next, the tube is partially evacuated of air. The tube is sealed and argon or neon are backfilled to a specified pressure according to the tube’s diameter. For argon-filled tubes, extra steps are required for mercury injection. Depending on the tube’s length and the climate, this can take between 10-40ul.
Neon gas emits red color. It glows with its distinctive red light at atmospheric pressure. There are more than 150 colors available now. Nearly every color except red can be produced with argon and mercury as well as phosphor. All positive-column discharge lamps can be called neon tubes, regardless of gas filling. In order of discovery, the colors were: blue (Mercury), Co2, white (Co2) and gold (Helium), then different colors for phosphor-coated tubes. The mercury spectrum is rich with ultraviolet light, which causes a phosphor coating to glow inside the tube. You can find phosphors in almost any pastel color.
Additional Notes
Jean Picard is best known for being the first astronomer to accurately measure the length of a degree on a meridian (longitude) line and then calculate the size of the earth. Barometers are devices that measure atmospheric pressure.
Daniel Preston, who provided technical information for this article, deserves special thanks. Preston is an inventor and engineer. He also serves as a member on the technical committee for the International Neon Association. Preston Glass Industries is owned by him.