Illuminating History

Welcome to Becoming Sage, where the ordinary becomes extraordinary! My name is Elan Baumgarten and I’m excited to illuminate a very important tool that has allowed humankind to rapidly increase their technological evolution. It is so important that an entire developing country’s GDP can be calculated just by measuring the output from this one invention. The system for this has to do with the amount of infrastructure that gets built up, illuminating the night sky with light output from those buildings and structures. It helps when accurate data can’t be gleaned from records or other sources. Today’s episode is on the light bulb! The first person that most think of when someone brings up the invention of the light bulb is Thomas Edison, and it is a fair thing to think. He was responsible for the first incandescent light bulb with his work around the year 1880. He was not the first to start working with light though. In 1835, British scientists and inventors were proving artificial electric light possible with the arc lamp. Those scientists and others around the world would work on the incandescent lamp for the next 40 years. They were largely tinkering with the filament, the substance that becomes illuminated when an electric current flows through it, creating heat. They also experimented with the actual contents of the bulb. Do you put inert gas inside? Do you vacuum everything out? These were important questions that scientists had to ask to bring us into the modern age of illumination that we all know. Lightbulbs used to have incredibly short life spans and were costly to produce - making them a poor replacement for candlelight until major changes were implemented. Edison and his team’s first objective was to fix the filament - allowing for longer lifespans. By 1879 they had developed a carbon filament. Edison also experimented with platinum filaments but decided that carbon was still the better option. These carbon filaments lasted for an average of 14 and a half hours, much longer than anything before. That doesn’t even compare to the filament that he would end up using for the next decade though. After some more research and experimentation Edison discovered that by using a bamboo-based filament he was able to give his light bulbs a lifespan of over 1,200 hours! He didn’t just improve the filaments though. Edison made a better vacuumed bulb that had less gas inside, as well as inventing what is now the standard for light bulb socket fittings. Edison’s creation, innovation, and manufacturing related to the light bulb has been disputed because of multiple people and companies also working on it with patents both in the U.S. and England. Eventually, through a series of mergers, two companies, one in England and the other in the United States, emerged to be the primary light manufacturers. The American company was a merger of the Thomas-Houston Electric Company, which was producing incandescent lamps under the patent of inventors William Sawyer and Albon Man, and Thomas Edison’s lighting company. They called it General Electric. Edison also merged with an English company owned by Joseph Swan after a series of legal battles regarding the rights to these creations. Incandescent light isn’t nearly as efficient as fluorescent light which is anywhere from 4-6 times more efficient. Fluorescent light was discovered in the 19th Century, just like incandescent light. Two Germans, a glassblower and a physician, discovered it. They took a long glass tube and sucked all of the air out - then they ran an electric current through it. It was named the Geissler tube. The Geissler tube is something known as a discharge lamp. In the 1890s, both Edison and Nikola Tesla conducted experiments with fluorescent lights; neither scientist actually produced them. They didn’t gain traction until the 20th Century when people started needing more efficient lights. The efficiency of a light bulb is calculated by dividing the light emitted by the watts that it consumes. They were eventually used in a number of different creations including neon lights, street lights, and fluorescent lights. The sudden use of fluorescent lighting is thanks to a man named Peter Cooper Hewitt. He created a bluish green light by shooting an electrical current through mercury vapor, all controlled by a ballast. The ballast controlled the strength of the current. His lamp was much more efficient than the incandescent lights that Edison produced. Unfortunately their use was limited because of the blue-green coloring. He patented his creation in 1900. Fast forward a few decades and we are into the 1920s and 30s when European scientists were experimenting with neon tubes that they had coated in phosphors. Phosphors are a material that are luminescent. Research programs for similar lamps in the United States were created and at the 1939 World Fair in New York they were demonstrated to the United States Navy. These lights became vastly popular in the United States. In 1973, designers once again set out to find efficient bulbs that could be used in residential spaces. They were prompted to do this by the oil crisis caused by an embargo from the Arab members of the Organization of Petroleum Exporting Countries. In 1976, Edward Hammer of General Electric successfully bent the fluorescent tube into a spiral which is known as the very first compact fluorescent light. GE shelved the design because of the high manufacturing costs. By the mid 1980s compact fluorescent lights, or CFLs, hit the markets. Early CFLs did have some problems like bulkiness, issues with fitting into fixtures, and an overall low light output. It’s been well over 30 years since CFLs were introduced to markets and they have become much more efficient both in their usage and their cost! Perhaps one of, if not the most common lighting tool of today’s world is the light-emitting diode, or as most people know them, LEDs. LEDs convert electricity into light using a semiconductor and are incredibly small, usually under a square millimeter. They don’t need reflectors or diffusers - instead LEDs project in a singular direction. All of these things are what make them the most energy efficient lights out there! There are even light implements that are primarily used for the screens of today’s technology, such as LCDs and OLEDs. Thank you for listening to Becoming Sage, where the ordinary becomes truly extraordinary. My name is Elan Baumgarten. Join us next week for another episode of extraordinary history!