LEDs (light-emitting diodes) produce light through the recombination of electrons and holes in a semiconductor material when an electrical current is applied.

Light-emitting diodes (LEDs) are a significant technological advancement in modern lighting and electronics. They operate based on the principle of electroluminescence, where a semiconductor material emits light when an electric current passes through it.

How LEDs Work

1. Semiconductor Structure: LEDs are made from semiconductor materials, typically composed of elements such as gallium arsenide (GaAs) or gallium nitride (GaN). These materials are doped with impurities to create two types of regions: n-type (excess electrons) and p-type (excess holes).

2. Recombination Process: When voltage is applied, electrons are injected into the p-type region and move towards the n-type region where holes are present. The electrons and holes recombine in the depletion region of the diode.

3. Photon Emission: This recombination process releases energy in the form of light (photons). The color of the emitted light depends on the bandgap energy of the semiconductor material—different materials will emit different wavelengths (colors) of light.

4. Efficiency and Lifespan: LEDs are known for their higher efficiency compared to traditional incandescent bulbs, as they convert more energy into light rather than heat. They also have a longer lifespan, often exceeding 25,000 hours of use.

Overall, LEDs represent a fusion of physics and engineering that enables efficient and durable lighting solutions, making them increasingly popular for various applications ranging from general lighting to sophisticated display technologies.