What is the Full Form of LED, its application and principle?

Safalta expert Published by: Saumya Sahoo Updated Sun, 18 Sep 2022 12:11 PM IST

About LED 

A light-emitting diode (LED) is a semiconductor light source that emits light when an electric current is passed through it. Electrons in semiconductors recombine with holes, releasing energy in the form of photons (packets of energy). The color of the light (corresponding to photon energy) is determined by the energy required for an electron to cross the semiconductor bandgap. White light is obtained by using layers of light-emitting phosphors on multiple semiconductors or semiconductor devices.  Check here Free Current Affairs Magazine DOWNLOAD NOW  

LED applications

LED applications can be divided into five main categories:

  1. A visual signal in which light travels more or less directly from a light source to the human eye to convey a message or meaning

  2. Lighting that reflects light off objects to give a visual response from those objects

  3. Measurement and interaction of processes without human vision

  4.  Narrowband photosensors in which the LED operates in reverse bias and responds to incident light rather than emitted light  

  5. Indoor cultivation, including cannabis.

Principle of LED

A light-emitting diode is a semiconductor light-emitting device that combines a P-type semiconductor with a high hole concentration and an N-type semiconductor with a high electron concentration. When a suitable forward voltage is applied across the PN junction, electrons and holes recombine and release energy in the form of light.


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What is LED?

A light-emitting diode (LED) is a semiconductor light source that emits light when an electric current is passed through it. Electrons in semiconductors recombine with holes, releasing energy in the form of photons (packets of energy). The color of the light (corresponding to photon energy) is determined by the energy required for an electron to cross the semiconductor bandgap. White light is obtained by using layers of light-emitting phosphors on multiple semiconductors or semiconductor devices.

What are the applications of LED?

LED applications can be divided into five main categories:

  1. A visual signal in which light travels more or less directly from a light source to the human eye to convey a message or meaning

  2. Lighting that reflects light off objects to give a visual response from those objects

  3. Measurement and interaction of processes without human vision

  4.  Narrowband photosensors in which the LED operates in reverse bias and responds to incident light rather than emitted light  

  5. Indoor cultivation, including cannabis.

Describe briefly the principle of LED.

A light-emitting diode is a semiconductor light-emitting device that combines a P-type semiconductor with a high hole concentration and an N-type semiconductor with a high electron concentration. When a suitable forward voltage is applied across the PN junction, electrons and holes recombine and release energy in the form of light.

What are the types of LED?

LED type

Various types of LEDs or light-emitting devices are available on the market. They differ in shape, size, and how the circuit is formatted. They are affordable and have better lighting and efficiency. It is also durable as it will last a long time.

  1. High-Power LEDs: As the name suggests, these LEDs provide higher output power. Consume more than 1 watt of power. Since they have higher power, the luminosity is also greater. They also last longer than CFLs (Compact Fluorescent Lights) and incandescent bulbs and are more environmentally friendly. The installation requires a cooling system as it gives off a lot of heat. High-power LEDs are mainly used in street lights, lamps, traffic lights, etc.

  2. Miniature LEDs: These types of LEDs are common these days. Small in size, fit quickly. It can be easily integrated into a circuit board and does not require any heating or cooling equipment. These are on the market in the 5V and 12V range. It is used in various electronic devices such as mobile phones and calculators.

  3. Application specific: Next, some LEDs are created to perform specific functions. Some application-specific LED examples are; Blinking LEDs, Bi-color LEDs, Tricolor, RGB tri-colour LEDs, Alphanumeric LEDs, and multicolors.

What are the advantages and disadvantages of LED?

Procs of LEDs

  • Energy saving: This is one of the important reasons to consider LED bulbs. This technology was developed to save 80% energy. In addition, LED energy does not generate heat or noise.

  • Durable properties: LED lights are durable enough to run long races. It is an LED bulb that can be used for many years at a reasonable price.

  • Eco-Friendly: Users are considering LED bulbs because they are eco-friendly and do no harm to the environment. LED technology does not require cadmium, lead, or mercury. The best part about this non-toxic technology is that it can be recycled with a minimum recycling rate.

  • Impressive Images with Low Maintenance

  • Costs: LED TVs provide impressive, crystal-clear images with vibrant colors. LED lights also converge with low maintenance costs.

Cons of LEDs

LED lights are expensive these days. Apart from that, the performance of an LED light is completely dependent on the temperature of the environment in which the light is placed. If the ambient temperature is high, the bulb will overheat and fail.

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