Indoor LED (Light Emitting Diode) lights work by using a semiconductor diode that emits light when electricity passes through it.
Here's a breakdown of the process:
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The Diode: An LED is a special type of diode, a semiconductor device with two terminals (anode and cathode) that allows current to flow in only one direction.
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Semiconductor Materials: The diode is made of two types of semiconductor materials: a p-type and an n-type. The p-type material has an excess of "holes" (places where electrons are missing), while the n-type material has an excess of electrons.
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The P-N Junction: When the p-type and n-type materials are joined together, they form a p-n junction. At this junction, some electrons from the n-type material diffuse across to fill the holes in the p-type material, creating a region called the depletion zone.
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Applying Voltage (Forward Bias): When a voltage is applied to the LED in the correct direction (forward bias), electrons from the n-type material are pushed across the junction into the p-type material, and holes from the p-type material are pushed into the n-type material.
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Recombination and Light Emission: When an electron from the n-type material meets a hole in the p-type material, they recombine. This recombination releases energy in the form of photons (light particles). The color of the light emitted depends on the energy gap between the materials, which is determined by the specific semiconductor materials used.
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Encapsulation: The LED is typically encapsulated in a plastic lens that helps to focus the light emitted.
In simpler terms:
- Electricity flows: An electric current passes through the LED.
- Electrons jump: Electrons move from one semiconductor material to another.
- Energy released: When the electrons jump, they release energy in the form of light.
- Light shines: This light is what you see as illumination.
LEDs are energy-efficient because they directly convert electricity into light with minimal heat waste, unlike traditional incandescent bulbs that produce light by heating a filament.
