Because incandescent bulbs were not running efficiently, research on electric light continued to expand. In the 19th century, Heinrich Geissler (glassblower) and Julius Plücker (physician) discovered that it’s possible to produce light by expelling almost all the air out from a long glass tube and letting an electrical current pass through it. This invention became known as the Geissler tube (type of discharge lamp), but it did not gain popularity until the 20th century, when scientists looked for ways to enhance its lighting efficiency. Discharge lamps became the origin of many modern lighting technologies like low-pressure sodium lamps, fluorescent tubes, and neon lights.
In the 1890s, Thomas Edison and Nikola Tesla experimented on fluorescent lamps, but it was Peter Cooper Hewitt who made a breakthrough in the early 1900s. He made a blue-green light by letting electric current pass through mercury vapour and integrated a ballast (a device that’s connected to the tube that regulates the current flow). Although Hewitt’s fluorescent lamps were far more efficient than incandescent bulbs, they were not as versatile because of their colour.
European scientists started researching neon tubes covered with phosphorus in the late 1920s and early 1930s. These findings began further studies, and by the mid and late 1930s, these improved fluorescent lamps were being demonstrated at the New York World’s Fair. After that we jump to around 1976, the birth of compact fluorescent light (CFL) signalled a new dawn in the lighting industry. However, the first CFLs were pricey, bulky, didn’t fit well with fixtures, had low light output and were inconsistent in performance. Because of these setbacks, the technology was further developed, and since the 1990s, considerable improvements were seen in the price, efficiency, and lifespan.
What comes next after fluorescents?
After years of research and development, the world was introduced to one of the fastest evolving lighting technologies at present, light-emitting diodes (LEDs). LEDs are a solid-state type of lighting that uses semi-conductors to convert energy into light and emit it in a specific direction, reducing the need for diffusers and reflectors, which ends up trapping light. LEDs are the brightest, most energy-efficient, longest-lasting lighting solution you can get currently, and it’s by far the most superior.
