LED lamps
LED lamps, or LED lights, are a modern type of lighting that employs electroluminescence, a technology first discovered in the early 20th century but only developed into practical applications in the 1960s. Unlike traditional incandescent bulbs that generate light through a heated filament, LED bulbs use solid-state lighting technology, which makes them significantly more energy-efficient—utilizing up to 75% less electricity. They also have a much longer lifespan, typically lasting over 25,000 hours compared to just 1,000 hours for incandescent bulbs.
Despite their advantages, LED lights can be more expensive to purchase upfront, which may be a barrier for some consumers. They also offer versatility by providing light in various colors and dimming options. However, there are concerns about potential adverse effects on vision and sleep patterns, particularly related to blue LED light exposure. As a result, consumers are advised to limit usage of these lights, especially before bedtime. Overall, LED lamps have become a dominant lighting choice in many regions due to their efficiency and longevity, marking a significant shift in lighting technology.
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LED lamps
LED lamps, also called LED lights or LED bulbs, are a type of lighting that utilizes electroluminescence. Electroluminescence was first discovered in the early twentieth century but did not evolve into LED lighting until the 1960s. Initially, LED lights were too short-lived, dim, and expensive for everyday use. However, over time, they improved beyond the capabilities of incandescent bulbs. In many regions, LED bulbs have overtaken incandescent bulbs as the dominant form of lighting.
LED lamps offer many advantages over traditional incandescent lighting. They use less electricity, offer light in a variety of colors, and last far longer than incandescent bulbs. However, LED lights are often more expensive than traditional counterparts, making them difficult for some people to purchase in bulk. Additionally, scientists have expressed concerns that LED light may be damaging to vision. For this reason, they have cautioned consumers to avoid prolonged exposure to particularly powerful LED lights, such as blue LED lights. They have also cautioned consumers to avoid utilizing LED lights before bed, as perceiving blue LED lights may interfere with the body’s circadian rhythm.
Background
Electroluminescence, the concept used in the creation of LED lights, was first discovered in 1907 by Henry Joseph Round. However, the light produced by Round’s experiments was extremely dim. Round decided that the phenomenon was not valuable in that form, and though further experiments were conducted, no major developments were made.
In 1961, scientists Gary Pittman and James Robert Biard continued Round’s work, creating an infra-red LED light. At the time, the duo was working on the creation of laser technology, and created their infra-red LED light by accident. However, because the light was not visible to humans, they decided that it had little practical use. The following year, Nick Holonyak Jr. created the first LED to produce visible red light. Throughout the rest of the 1960s, researchers refined the concept of the LED, working to increase its visual output and its electrical efficiency.
Some LED lights were marketed as commercial products during the 1960s. These lights were created to serve as replacement lights in appliances and vehicles. However, at the time, LED lights were far more expensive than their incandescent counterparts. Additionally, the LED lights of the 1960s were fairly dim. This limited their primary usage to indicators, not genuine light sources. For these reasons, commercial LED light sales remained low. Though the price of LED lights dropped in the 1970s, the product’s limited applications continued to hold back sales.
Japanese scientist Shuji Nakamura significantly improved the technology used to make blue LED lights, vastly increasing their brightness. This breakthrough, which eventually earned Nakamura a Nobel Prize, also helped make commercial LEDs bright enough to serve as sources of illumination. Through enhancing the design and brightness of blue LEDs, manufacturers soon developed white LEDs, further increasing their potential for everyday usage.
Though early white LED flashlights were expensive to manufacture and less efficient than their modern counterparts, the technology utilized in LED lights continued to improve. The first commercial LED flashlight entered the market in 2001. Soon after, LED light sources slowly began phasing out incandescent light sources.
Overview
LED stands for “light emitting diode.” Though past forms of LED lighting were inefficient, modern LED lighting uses significantly less power to produce light levels similar to those produced by incandescent lights. This made LED lights more appealing to consumers, resulting in their rapid adoption across various industries.
Incandescent bulbs generate light by heating a piece of metal called a filament. When heated to extreme temperatures, the filament glows. The heat of the filament is greatly increased by a vacuum maintained within the glass inside the bulb. LED bulbs do not work in the same manner. Instead, LED lightbulbs use solid state lighting (SSL) technology. They use semiconductor devices called diodes, which conduct electricity. Through manipulating the paths of electrons, careful arrangements of diodes can be used to create visible light. When scientists learned to make LED lights as bright or brighter than traditional incandescent bulbs, companies began to produce replacement bulbs for use in homes.
LED lights offer many advantages over incandescent bulbs. Because the light is not being produced by a heated piece of metal, LED bulbs do not get hot. This reduces the capacity of the bulb to start fires and means that bulbs can be changed without the risk of burns. Additionally, because LED bulbs do not allow energy to escape as heat, they create light in a much more efficient manner than incandescent bulbs. In most cases, LED lights utilize up to 75 percent less energy than their traditional counterparts.
Because their ability to produce light does not rely on heat, LED bulbs are much more stable than incandescent bulbs, allowing them to last for significantly greater periods of time. The average LED lightbulb lasts for more than 25,000 hours of use. The average incandescent bulb lasts for just 1,000 hours of use. Many LED bulbs also contain diodes that produce different colors of light, allowing consumers to change the color of their bulbs at will.
Despite the many advantages of LED lightbulbs, some factors still limit their spread. Most LED bulbs are significantly more expensive than incandescent bulbs when purchased. Though they may cost a homeowner less money in utility costs by consuming less power, equipping a large house with LED lightbulbs may be cost prohibitive.
Additionally, many scientists have expressed concern that LED light may be damaging to the human eye. They have theorized that LED has the potential to disrupt the human sleep schedule in a different manner than incandescent light. For these reasons, many scientists recommend limiting exposure to powerful blue LED lights.
Bibliography
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