A light-emitting diode (LED) is a semiconductor light source.
LEDs are used as indicator lamps in many devices, and are increasingly used for
lighting. Introduced as a practical electronic component in 1962, early LEDs
emitted low-intensity red light, but modern versions are available across the
visible, ultraviolet and infrared wavelengths, with very high brightness.
When a light-emitting diode is forward biased (switched on), electrons are able to recombine with holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. An LED is often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern. LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved robustness, smaller size, faster switching, and greater durability and reliability. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output.
Light-emitting diodes are used in applications as diverse as replacements for aviation lighting, automotive lighting (particularly brake lamps, turn signals and indicators) as well as in traffic signals. The compact size, the possibility of narrow bandwidth, switching speed, and extreme reliability of LEDs has allowed new text and video displays and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances
When Light-emitting diodes are used in LED signs, it allows for this very small but very bright light that is similar in brightness to neon to do amazing things. LED signs are made up of many small individual LED light bulbs that can be independently programmed which allows for some amazing animation possibilities. This is the primary reason that led signs with animation have gained so much popularity over the years. Las Vegas used to be referred to as the “neon capital of the world” (among other things) but today, more than one half of the signs and displays there are LED due to its amazing and versatile features. LED signs are the way to go in digital advertising. LED signs are more advantageous in terms of durability, energy efficiency, and reliability than Neon and other forms of lighting.
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