The Invention of Incandescent Lighting
Incandescent light bulbs turn electricity into light by sending an electric current through a thin wire filament typically made of tungsten metal. The filament’s resistance heats the bulb to a point where the filament gets to hot that it glows, producing light. This is why traditional bulbs get so hot when they are turned on.
Long before Thomas Edison patented the first incandescent bulbs in 1879 and 1880, British inventors determined electric light was possible with the arc lamp. In 1835, the first constant electric light was demonstrated. William Sawyer and Albon Man received a U.S. patent for the incandescent lamp, and Joseph Swan first patented the light bulb in England. For the next 40 years, scientists around the world worked on the incandescent lamp, tinkering with the filament and the bulb’s atmosphere, but the combinations extremely short lifespans, were too expensive, or used too much energy to produce light.
In many textbooks, Thomas A. Edison is credited with inventing the modern incandescent light bulb; however, history reflects countless chemists, physicists, and inventors clamored for the honor and substantial payoff (energy.gov).
In 1878, Edison he could create a safer, cheaper, and more reliable incandescent light to replace existing gas lights in just six weeks and gathered a team of 14 engineers, machinists and physicists to do so. The announcement caused gas company stocks to plummet.
Edison and his team created several prototypes which lead to patent filings in 1879 and 1880. Simultaneously Sir Joseph Wilson Swan, who had been working on bulb concepts for thirty years, patented filament-based bulb technology and demonstrated it. There was debate on whether Edison’s light bulb patents infringed on previous patents. Eventually Edison’s U.S. lighting company merged with the Thomson-Houston Electric Company — the company making incandescent bulbs under the Sawyer-Man patent — to form General Electric, and Edison’s English lighting company merged with Joseph Swan’s company in England to avoid patent infringement suits.
Edison is however credited for creating a better vacuum pump to fully remove the air from the bulb and developing the screw base for light bulbs (a standard still used today). Edison went on to develop the centrally located electric generator, the first electric utility and the first electric meter.
The tungsten filament by European inventors in 1904. These new tungsten filament bulbs lasted longer and had a brighter light compared to the carbon filament bulbs. In 1913, Irving Langmuir figured out that placing an inert gas like nitrogen inside the bulb doubled its efficiency. Scientists continued to make improvements on the bulbs, but by the 1950s, researchers still had only figured out how to convert only 10% of the energy into light!
The Halogen Alternative
The halogen light bulb was introduced in 1959 by General Electric. These light bulbs, reduced the uneven evaporation of the filament and darkening of the envelope by filling the lamp with halogen gas rather than an inert gas. Halogen bulbs also lasted longer with an average life of 1,500 hours, and consumed only 15 percent less energy (they still became very hot!).
The Introduction of CFLs
The U.S. oil crisis in the 1970s sparked interest in renewable sources of energy and energy-efficient residential lighting. Lighting engineers began to adapt fluorescent lighting for residential use. Fluorescent lamps had been in use since the 1930s, but they were mainly used for commercial and industrial lighting.
In 1976, Edward E. Hammer, an engineer at GE, bent a fluorescent tube into a spiral shape, creating the first compact florescent lights (CFL). CFLs drive an electric current through a tube that contains argon and mercury vapor. This process creates ultraviolet light that translates into visible light.
During the mid-1980s, the first CFLs began to hit the market starting at $25 to $35. Consumers were hesitant to embrace the new lighting technology due to its price, size, and performance. Early CFLs were big and bulky, and did not fit in many light fixtures. They light bulbs also emitted a low light and performed inconsistently.
Subsequent improvements in CFL prices, performance, and efficiency made them the ideal choice for energy conscious homeowners and business owners. CFLs use 70% less energy than traditional incandescent light bulbs. They also have an average life 10,000 hours, about ten times longer than the average life of an incandescent bulb.
However, it takes CFLs a few moments for them to warm up and reach full brightness. That means they’re not ideal in spots where you want lots of light as soon as you flip the switch, such as a basement stairway. Some struggle to produce light in cold outdoor temperatures. Many cannot be used with a dimmer switch.
CFLs also contain a small amount of mercury, which is very harmful to both your health and the environment. That means it’s bad news to break one (be sure to clean it up safely if you do), and recycle them carefully as you would hazardous household chemicals (check with your community’s waste removal service for instructions).
The Emergence of LED
In 1961, James R. “Bob” Biard and Gary Pittman at Texas Instruments discovered the first light-emitting diode while attempting to create a laser diode. In 1993, Shuji Nakamura developed the first bright blue light-emitting diode, the last component needed to create bright white LED light. Shortly thereafter, scientist experimented with blue, red, and green diodes by coating them with phosphors to make them appear white.
LED light bulbs work by bringing together currents with a positive and negative charge to create energy released in the form of light. The result is a fast source of light that is reliable, instantaneous, and able to be dimmed.
What sets LEDs apart from incandescent bulbs and CFLs is just how long they last. LED light bulbs can last anywhere from 20,000 to 50,000 hours, or up to five times longer than any comparable bulb on the market. Historically, the long life has come at a cost, however as production has increased the cost of LED bulbs have fallen to prices competitive with other alternatives. LED bulbs rarely burn out and rarely need changed. LEDs are composed of durable plastic materials rather than glass, also making hazardous broken glass when a light bulb breaks a thing of the past.
Today, there are a wide variety of American and international LED manufacturers. GE reorganized and established GE Lighting in 2020 to focus on opportunities. Phillips, a dutch incandescent lighting company founded in 1891, continues to provide lighting technology and now offers LED. American providers such as Feit (California) and Acuity brands (Atlanta) produce LED lighting produces domestically.
The Future of LED
In North America alone, the LED lighting market is expected to register incremental growth of close to USD 7 billion by 2022 (Technavio 2018). The market is expected to grow at a compounded annual growth rate of about 12% to 2022. Manufacturers are pouring considerable effort and research dollars into the development of lower cost manufacturing technologies and produce developments in an attempt to capture growth, providing consumers with lighting technologies with enhanced features (such as wifi integration and color adjustability) in the future at lower cost.
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