Once it is trapped in a tube, neon becomes invisible and dull. Then it can be zapped by electricity. Neon literally pulled from thin air, became the brightest light in the modern world. It is a symbol for progress and an integral part of the electronic age.
Philip Marlowe was the hard-boiled detective hero in Raymond Chandler’s detective novels. He was correct about neon. The lights that lit up the night sky in more than a thousand cities had been invented out of nothing. The air itself was the source of the colorful words and images. These mysterious gases were extracted from the atmosphere and placed in glass tubes and then zapped by electric current to produce luminous reactions. Lights fueled by neon and other noble gases were icons for commerce and entertainment in the 20th century. They illuminated the modern age. Early computers and calculators used small neon tubes to create circuits and display circuits. Many of the elaborate neon signs are no longer in use. However, these tubes with gas filled inside still shine brightly on a smaller scale and are treasured for their unique light.
Aristocrats of the Air
The history of neon began in 1890s with Sir William Ramsay, a Scottish chemist. Ramsay is best known for discovering four noble gases (neon argon krypton and xenon). He also identified and characterized helium, a second noble gas, and won the Nobel Prize. These six elements form a family distinguished by their inability to bond with other molecules. These noble gases were named for their “nobility”, their insolence.
It took a while before the atmosphere lost all its secrets. The mystery gas was discovered by Henry Cavendish, a prominent chemist, in 1785. They began to attack air using brute-force methods, including reaction, combustion, and absorption, in 1894. This was to remove every atom of oxygen and nitrogen from the atmosphere. Red-hot copper was used to remove oxygen from the air in an early experiment. The deoxygenated oxygen was then passed through red-hot magnesium and soda lime. Copper oxide and phosphoric acidide were used to remove the nitrogen. The remaining oxygen and nitrogen were removed by further steps. They named the residual gas argon (derived in part from the Greek word for “the inactive, lazy one”)
Although argon is less than 1% in the atmosphere, Ramsay believed that other rare gases were hidden in the air. These elements were discovered by Ramsay and Morris W. Travers in the summer 1898. They began with purified argon that had been liquefied at low temperatures. Then they added heat to separate gases that could be boiled at temperatures above and below the boiling point of argon. They discovered neon, krypton and xenon.
These rare gases may not be visible to the naked eye but glow with brilliant colors when they are sealed in glass tubes and energized by high voltage. These gas-discharge tube were named after the electric discharge that caused them to light up. They would be the basis of neon lamps. Ramsay found the neon light to be particularly striking. Ramsay described neon’s light as a “bright flame-colored light consisting of many reds, oranges, and yellow lines” in his 1904 Nobel Prize lecture. Travers was even more eloquent. The tube’s crimson glow was an unforgettable sight that you will never forget. It was worth all the hard work of the past two years and all the challenges that remained before the research was completed. . . We were the only ones who saw a glow like this.
Exploiting the Air
Liquid air, especially oxygen, was first used in theater lighting and industrial welding in the late 19th century. The Joule-Thomson Effect is the basis of all liquefying gas techniques. This effect can be seen in your home or office whenever you use pressurized air to dust your computer keyboard. As the air expands through a nozzle, it drops temperature and condensation forms. Ramsay was working on isolating his gases when the first practical methods for liquefying air on large scales were discovered. He made sure to mention William Hampson in his Nobel Prize lecture.
Like Hampson, Carl von Linde, and many others in England and Germany, Georges Claude, a Parisian engineer and inventor, used the Joule–Thomson effect on liquefying water. This allowed for huge amounts of production (up to 10,000 cubic metres per day). Paul Delorme, his former schoolmate, was also his co-founder of L’Air Liquide in 1902. It grew quickly to become a multinational company. Claude also conducted scientific research while selling liquid oxygen for industrial uses. He had initially hoped to find more noble gases by analysing large volumes of liquefied oxygen, but he was forced into admitting that after Ramsay, there was no further work. His next project combined leftover neon from his air liquefaction with his disapproval of the excessive brightness of electrical lighting.
Lines of Light
Gas tubes were not just used by Claude to provide light. Inventions were inspired by Thomas Edison’s commercial success with incandescent lightbulbs. Daniel McFarlan Moore was an Edison employee who filled 10-foot glass tubes under low pressure with carbon dioxide or nitrogen and added electrodes at the ends. These “Moore lamps”, which lit brightly when electrified, were much more efficient than the incandescent carbon-filament bulbs. Although the lamps were useful for general lighting in shops and offices, they were costly to install (a glass plumber had to connect them on-site), required high voltage electricity and were prone to leaking. His company was bankrupted in 1910 when better incandescent lamps using tungsten filaments replaced Moore’s tubes.
Claude quickly discovered that Moore’s idea of neon was more than switching gases. His tubes produced a brilliant glow but the impurities that were released from the hot electrodes quickly dimmed it. The problem of metallic buildup around electrodes caused the tubes to flicker too quickly, but a carbon filter fixed that. Claude used larger electrodes to keep the tubes cooler. The tubes burned brightly and consistently for as many as 1,200 hours.
Claude was finally successful and filed his first patent in 1910 for neon lighting. He demonstrated his invention in December at the Salon de l’Automobile, Paris Motor Show. The exhibition building was filled with thousands of incandescent lamps that glowed off the shiny metal cars below. Two neon tubes measuring 40 feet glowed bright orange-red outside, on the colonnade. Modern technology was displayed: The newest cars and lighting, made possible by Paris’s rapidly expanding electrical network.
Although red neon is not the best for general lighting, Claude insisted that neon could be used in certain situations. This included illuminating monuments or in advertising where neon was “the most dazzling and appealing of lights, the better it is.” In a Parisian barbershop, on the Boulevard Montmartre, Claude placed the first ever neon advertising sign. Soon, a large sign on the roof for Cinzano, an Italian vermouth manufacturer, was installed. Illumination for the entrance to the Paris Opera soon followed. To make the most of his invention, Claude founded Claude Neon to sell neon signage franchises. Although the franchises were expensive ($100,000 plus royalties), there were many openings around the globe, particularly in major American cities. The neon sign was quickly becoming a household brand. Although the first neon signs were simple, animation and a variety of colors would follow later. Business owners competed to trace their signatures onto buildings and rooftops. Claude’s sign-monopoly lasted into the 1920s and was eventually broken by former employees who leaked his trade secrets.
A new sign language
It was not in New York or Las Vegas that the first neon signs were created in the United States. In fact, the population of Los Angeles was only a few thousand at the time. Earle C. Anthony, an entrepreneur, was a pioneer in many modern businesses, including radio, automobiles and gas stations. He founded the first California Packard Motor Car Company dealership in 1915. This luxury brand was a staple of Californian life. Anthony saw Claude’s neon signs while visiting Paris. He then ordered a promotion for his downtown showroom in 1923. Two signs with the words “Packard” in elegant font were traced in orange neon tubing and a clear blue border. This was most likely made by adding mercury to neon. Anthony made a good investment by purchasing the signs for $1,250. This is half the cost of a single-six Touring five-passenger Packard Single-Six Touring car in 1923. They caused traffic jams because people stopped to admire their intense glow.
It was not in New York or Las Vegas that the first neon signs were created in America, but in Los Angeles.
The neon was unstoppable from that moment on. It was truly “the new one”, a symbol for modern industry, commerce and progress in a world still reeling from the horrors of World War I as well as the effects of Great Depression.
“Darkness brings out a million bright electric signs, making the night live in New York, London, Shanghai and Denver. A new sign language is available. . . Corning Glass Works’ 1937 advertisement proclaimed, “Written in glass!” It supplied neon tubes and supplies. Claude’s use neon at the Paris Motor Show was undoubtedly a sign of the times, as neon quickly became a part of American automobile culture, especially in the United States. The American interstate highway system was developing and neon signs promoted businesses catering to motorists. New York, Los Angeles and Las Vegas were all famous for their neon signs, which enticed people to accept and deny nighttime pleasures such as going to the movies, eating at restaurants, gambling and dancing.
While many people learn how to make neon signs from working with experienced sign makers, a few trade schools, such as the Egani Neon School in New York City, also teach the technique. A sign maker would start by drawing a design on an asbestos sheet. Then heat a glass tube with a torch or burner to make bends and curves. He then blows through the tube frequently to prevent it from breaking. The next steps were to attach electrodes to the tube and to evacuate the air inside. Finally, the interior was “bombarded” with high voltage to clean it. The tube was then sealed with small amounts of gas, usually a neon-argon mix, sometimes with a bit mercury. Finally, the tube was “aged” by an electrical current to remove any impurities and maintain a constant luminosity. For durability and enhanced light, the tubes were mounted to a support plate made of metal. The sign was completed once the electrical apparatus had been added.
There were more than 40 color combinations possible by changing the gas mixture or coating the tubes. Despite the limitations of this delicate and difficult medium, there were many forms and shapes possible. Block letters, flowing cursive text, combinations of lines or geometric designs, as well as pictures of any kind, from a shoe or fish in the shop window to elaborate, large-scale moving signs affectionately called “spectaculars”. These signs dazzled the eye with elaborate timing devices that activated tubes in succession. They displayed outlines of huge dancing showgirls or speeding trains. Spectaculars required hundreds of feet of tubing, miles of electrical wiring and were masterpieces in art and technology.
Neon was not just used to illuminate signs. In the 1950s and 1960s, neon tubes were key components in some digital circuits. Because electricity works in neon tubes, this unusual application was possible. Only when a tube is lit, electrons flow through it. A neon tube must be lit at a voltage higher than the one needed to keep it lit. A tube can be controlled by small voltage changes (seen as light) to maintain a voltage between on and off. The tube could be used to regulate the flow of current to control digital circuits by being a binary switch.
These neon switches can be connected together to make circuits for a variety of purposes, including simple accounting and measurement of events that happen faster than human eyes can count. A 1961 advertisement in a magazine stated that glow lamps filled with Airco neon make computers think faster. The neon glow lamp is what makes the electronic computer possible. It allows for dazzling speed, compactness, and economics. . . Many of the amazing advances in defense and business technology would be greatly slowed.”
Neon was truly ‘the new one’, a symbol for modern industry, commerce and progress in a world still reeling from the traumas of World War I, the Great Depression, and other effects.
Another advantage of neon tubes was their use in computers and other technical equipment. They ran cooler than incandescent bulbs and were therefore more efficient, making them ideal for use as indicators lights and displays. The Nixie tube, which is short for “Numeric Indiator eXperimental Number.”) was a common neon display. The Nixie tube, which was introduced in 1955, is the “Numeric Indicator eXperimental No. 1” type. The small neon bulb featured wires that resembled numerals, letters or other symbols. They lit up when the current was turned off.
The ANITA Mk VII, and Mk VIII electronic desktop calculators may be the greatest electronic success of Neon. They were invented by Norbert Kitz, a British Bell Punch Company employee. The display of the ANITA machines had a Nixie tube look. This feature was highlighted in an advertisement: “Answers to questions are recorded in large, lit-up figures that defy you from misreading them.”
The calculating logic was driven by neon-filled switching tubes inside the ANITAs. ANITAs were introduced in 1961-62 for 355 Pounds Sterling (roughly $1,000 today) and sold at a rate of 10,000 per annum to businesses such as banks, accounting firms, department stores, and other businesses. ANITA calculators had a size of 1 by 1.5 feet (31 cm by 46 cm) and a weight over 30 pounds (14 kg) each. However, they were quieter and more efficient than older mechanical calculators and smaller than the large (and expensive) computers of the time. This 1965 article explains:
The tubes are an accountant’s dream. A typical tube today has a life expectancy that is several thousand times greater than the traditional thermionic [vacuum] tub, even though they use voltages of the exact same order. They are cheaper than vacuum tubes or semiconductor devices. They don’t require expensive materials or high purity manufacturing.
However, neon tubes were almost obsolete by the 1970s. Transistors were the most popular electronic switching elements and light-emitting devices (LEDs) started to replace Nixie tubes. However, neon still shines brightly in DIY electronics. Hobbyists today seek out vintage Nixie tubes to build clocks or a watch. Some even create retro-style neon circuits.
Neon: Old and new
The reign of neon in signage was also very brief. Neon signs were affected by nighttime blackouts in the United States during World War II. Many large neon signs were not relit. New types of plastics and fluorescent tubes made it possible to replace them with cheaper, lower-maintenance signs. Many neon signs that were no longer in use were considered eyesores by many municipalities. However, dedicated preservationists and collectors worked hard to save and restore this authentic Americana.
Today, neon signs are usually small and simple. However, the 1970s saw the start of a small-scale revival in neon that continues to this day. Sign makers were attracted to neon’s retro look and appeal. They bent tubes to make signs in different styles and passed their knowledge on to the next generation. Architects used neon to accent buildings both inside and outside. Artists explored new avenues with neon, using light to create abstract sculptures.
Even though giant television screens and lighted billsboards have replaced the neon “spectaculars”, neon still lights up the night in towns and cities around the world, from Las Vegas to Tokyo, and everywhere in between. What about the original neon signs of the United States? Although Packard cars have long since disappeared, Earle C. Anthony’s showroom in downtown Los Angeles remains. A replica neon sign advertising the new function of the building is visible above the entrance. It glows in brilliant blue-white: “Packard Lofts.”
Xenon freezes the moment
While all noble gases can produce stunning illumination, xenon was a key player in the development and use of flash photography or high-speed. The xenon-filled tubes, which are filled with xenon, produce intense, brief bursts light that can freeze film motion.
Harold Edgerton, an electrical engineer professor at the Massachusetts Institute of Technology invented high-speed photography. He used many types of flash technology including strobe lamps. One of his most famous images is a milk droplet with a crown-shaped shape captured in mid-splash. Edgerton used argon or mercury for his first flash lamps, but he switched to xenon during the 1940s. Xenon flash tubes proved to be a great choice for color photography. The glow of xenon in a discharge tube, unlike neon’s bright red or argon’s purple, is very similar to sunlight. This allows photographers to capture natural color indoors better than with argon and neon.
Professional photographers could not use the original xenon flash tube and its associated electronics, which were developed in 1940s. Miniaturized xenon flash tube were made small enough to be standard features on regular cameras by the 1970s. Although light-emitting diodes, or LEDs, are used to flash cell phones and digital cameras, most cameras, especially high-end, still benefit from the natural colors and intensity of xenon light. Think of xenon next time you are taken with a flash.