Electroluminescence
Electroluminescence is a scientific process in which an electrical current stimulates a material to emit light. Discovered in the early 20th century, this phenomenon became commercially viable in the 1950s when scientists began developing electroluminescent lamps. The process involves passing an electrical current through a semiconductor, which contains small holes, allowing electrons to move and generate visible light. Electroluminescent devices, including LED lights and displays, are known for their energy efficiency and longevity, making them suitable for various applications such as indicator lights and screens in electronic devices.
While they consume less power and produce minimal heat, which is advantageous in temperature-sensitive environments, some types of electroluminescent lighting can be dimmer compared to traditional lighting options. Additionally, initial development and production costs were high, although advancements have made these technologies more accessible. Despite these challenges, electroluminescent lighting has largely shifted from niche applications to widespread use, particularly in home lighting and digital displays, reflecting its growing importance in contemporary technology.
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Electroluminescence
Electroluminescence is a scientific process in which an electrical current causes a substance to emit light. It was first discovered in the early twentieth century but was not commercially utilized until the 1950s. Electroluminescence functions by running carefully controlled electrical currents along semiconductors filled with tiny holes. As the current passes through the semiconductor, the electrons are forced to travel over the holes, creating visible light. By controlling the current and semiconductor, scientists have created electroluminescent devices in a variety of brightness levels and colors.
Modern electroluminescence offers numerous advantages over more traditional forms of lighting. It requires very little electricity to operate and lasts for far longer than incandescent bulbs. This makes it ideal for indicator lights, electronic screens, and other important roles. It can also be found powering electronic billboards and lighting homes in the form of LED lights. However, many types of electroluminescence are dimmer than other forms of lighting, making them inefficient for lighting larger spaces. Additionally, many types of electroluminescent lighting are more expensive than traditional alternatives.
Background
Electroluminescence was first observed under scientific conditions by the researcher Henry Joseph Round in 1907. At the time, Round was researching silicon carbide, not forms of illumination. However, he reported that when a current was passed through a silicon carbide detector, it created a faint yellow light. At the time, scientists did not see any significant commercial uses for this phenomenon.
Though scientists continued experimenting with electroluminescence throughout the 1910s and 1920s, the next breakthrough would not occur until 1936. George Destriau discovered that when an electric current was applied to zinc sulphide, the substance would glow in a manner similar to Round’s observations. Destriau coined the term “electroluminescence” to describe this phenomenon.
Following the end of World War II, scientists continued researching electroluminescence. They hoped that, through harnessing the phenomenon, they might be able to create a new form of commercial and industrial lighting. Scientists combined electroluminescent phosphors and steel plates to create the first electroluminescent lamps in the 1950s. During that period, scientists theorized that they would be able to use electroluminescence to create extremely bright, long-lasting lamps. However, in practice, they were only able to create lights that lasted for roughly five hundred hours. Additionally, the process for creating such lights was both difficult and expensive.
During the 1970s, numerous major electronics manufacturers believed that electroluminescence would be a primary lighting and visual device in the future. For this reason, they began assigning teams of researchers to develop electroluminescent devices. Specifically, many believed the electroluminescent devices would replace liquid crystal displays (LCDs), allowing for greater contrast and visual clarity.
In 1981, the first electroluminescent displays (ELDs) that could display multiple colors were released. When the electroluminescent properties of blue phosphorous were explored in 1993, the variety of colors available to ELDs quickly increased. Throughout the 1990s, ELDs continued to compete with established LCDs.
During the twenty-first century, electroluminescent lamps, also known as LED lights, rapidly grew in popularity. These devices slowly began to replace traditional incandescent bulbs. Though they were more expensive than incandescent bulbs, they used less power and lasted for much longer periods. Many LED bulbs could change their colors also, allowing consumers to adapt their lighting to their current needs.
Overview
Electroluminescence is a scientific phenomenon that uses the careful control flow of electricity to create visible light. It most commonly occurs when an electrical current is passed through certain materials. Unlike other forms of electrical illumination, electroluminescence does not emit heat.
In order to create electroluminescence, electricity is passed through a semiconductor filled with tiny holes. A semiconductor is a substance with an electrical conductivity value somewhere between that of a conductor and an insulator. As the electrical charge passes through the semiconductor, electrons are forced to travel over large numbers of tiny holes. The specially charged electrons travel through the air as photons, which can be perceived by the human eye. By varying the types of semiconductors and the electrical current that passes through them, scientists have created electroluminescent devices that produce light in various colors and levels of brightness.
Electroluminescent devices offer a variety of advantages over other sources of lighting. They require relatively little electricity to function and may last for extremely long periods without malfunctioning. Additionally, because the reaction that causes electroluminescence does not generate heat, they are ideal for temperature-sensitive environments. Though electroluminescent devices were once difficult and expensive to develop, their prices have become much more affordable as they were adopted by various industries across the world.
Some of the earliest adopters of electroluminescent lighting were the automobile and aircraft industries, which used small electroluminescent devices to illuminate display panels. This ensured that important indicator lights could reliably be illuminated with little to no maintenance. In the modern era, electroluminescent lighting has been adapted for a variety of purposes. Its low power consumption and small size make it ideal for lighting the screens of many electronic devices. This includes both small electronic devices, such as cellular phones and personal computers, as well as large electronic devices, such as digital billboards. In the form of LED lamps, electroluminescent lights have also overtaken incandescent lighting as the dominant form of home lighting throughout much of the world.
Despite its numerous advantages, electroluminescent lighting is not without drawbacks. Though they require comparatively little electricity, powering electroluminescent devices requires a significant amount of voltage. This is not a problem when a device must be connected to a power line to function. However, battery-operated devices will require a converter circuit to provide the necessary voltage. Additionally, certain types of electroluminescent lights struggle to produce high lumen ratings, making them inefficient for lighting large indoor spaces.
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