The Technology Behind the LED Light (Complete Guide)

We hear the word LED lamp here and there, but what exactly is LED lights and how does it work? LED stands for Light Emitting Diode. An LED lamp is thus a lamp made up of one or more high-intensity LEDs.

A common misconception that many people have is to mistake LED lamps for LED incandescent lamps, but LED is one thing and incandescent lamps another. In other words, they are not the same.

It was a Russian named Oleg Vladimirovich Losev who invented the LED during the 1920s. However, it was not until 1962 that a LED in the visible light spectrum developed. At present, we find LEDs both in the visible light spectrum and above and below, that is, ultraviolet and infrared LEDs.

Three Japanese researchers were awarded the 2014 Nobel Prize in physics for inventing the blue LED. When award winners in the early 1990s received the strong blue rays from their semiconductors, the doors were opened to change the lighting technology from the ground up. Red and green LEDs had been around for a long time, but without the blue light, white light could not be created. But the blue LED remained a challenge ever since the 1960s.

An LED consists of several layers of semiconductor material. When the diode is used with direct current, the light is produced in the active layer. The light generated is decoupled directly or through reflections. In contrast to ordinary stretch reflector lamps, which emit a continuous spectrum, an LED emits light of a certain color. The color of the light depends on the semiconducting material used. Different voltages are necessary to use the diode in forwarding bias.

LEDs are semiconductor crystals. Depending on the composition of the crystal compounds, they emit light in the colors red, green, yellow, or blue as current flows through them. Using an additional yellowish fluorescent layer, blue LEDs also produce white light (luminescence conversion). Another method of producing white light is to mix red, green, and blue LEDs (RGB). This is mainly used since the priority is not generally white light, but rather decorative effects with different full colors.

With the three RGB colors, any number of color tones can be mixed with different proportions of the individual colors. In this way, LED lighting can create a fascinating world of experiences.

How is the LED built up and how does it work?


The LED is a type of semiconductor diode that has the property of only passing current in one direction. That is, it is just like in a regular diode to send current only in one direction in an LED. Therefore, if you connect a faulty LED, no current will pass through, and no light will be emitted from the LED.

The LED is not larger than a grain of sand and consists of several layers of semiconductor material gallium nitride (GaN) and its alloys. In the n-layer there are many free negatively charged electrons, while in the p-layer there are no electrons, where the positively charged holes dominate. Electrical voltage drives electrons and holes against each other, in the meeting, light is emitted. The wavelength of light depends entirely on the semiconductor. The blue light is at the short-wavy end of the rainbow and can only be generated in certain materials.

The two biggest challenges, which no one previously managed, were to build up the gallium nitride crystal and to create an effective β-layer. The award winners also succeeded in increasing the lamp’s efficiency by blending indium (In) and aluminum (Al).

The fact that LEDs have become the obvious replacement is fully understandable. A modern 9 W LED light is as bright as an old 60 W incandescent lamp. Furthermore, a LED lamp lasts much longer, can be made much smaller, and (unlike low energy bulbs) contains no mercury.

Blue is needed to create white

Red, green, and blue light together emit white light. There are two ways to build white LED lights. Blue LED light causes material in the lamp to shine in red and green. Then all the colors blend, and out comes white light. The second way is to build a lamp of three LEDs – blue, red, and green – which the eye perceives together as white.

Compared to the old light sources, LEDs require less energy (measured in watts) to emit light (measured in lumens). Material consumption is also decreasing. In addition, the LED lamp does not contain mercury.

Power LED

Power LED is the name of a LED with very high light intensity in relation to power consumption. LEDs are sensitive to heat, and so are Power LEDs. By dissipating the heat that is primarily developed by Power-LED, you can maintain the luminous flux which otherwise decreases with temperature increase. Also, the lifespan of an LED is affected by heat and it is therefore important in strong Power LEDs where the heat output is relatively high, to lead it away so as not to damage components and maintain the luminous flux.

Area of use

If we generally look at where LEDs, ie LEDs, are used, we will find, among other things, status indicators on, for example, your stereo, the remote control (IR LED), LED TV, LED printers (formerly laser printers), modern traffic lights and more.

The LED is used extensively in our society and the LED lamp is only one of the few uses for the LED.

An LED lamp has the following important advantages:

  • Does NOT contain mercury
  • Usually lasts up to about 25,000 hours or more. This is 25 times longer than a regular incandescent light or twice as long as today’s low energy light.
  • Saves at least as much energy as today’s low-energy lamps.
  • Not shock-sensitive or temperature-sensitive
  • Full brightness immediately


  • The technology is under development in terms of brightness, color rendering, and manufacturing cost. It makes it easier to read and examine for what purpose different lamps are suitable.
  • Not all LEDs have a really “warm” light. The development is fast moving forward and it can distinguish a lot between LED lamps A and B.

How do I dim a LED lamp?

The light sources in LED lamps are LEDs. Light is generated from them when electricity passes through the diodes. The more electricity, the more light is generated and vice versa. At dimming, a small amount of current passes, and thus less light is generated and it is then called that the lamp dims.

How do you know if an LED light is dimmable?

Usually, all models of LED lights have a dimmable version. However, make sure that the product description or specifications indicate that the lamp is dimmable. Here you can easily buy dimmable LED lights.

What is required to dim LED lights?

To be able to dim an LED lamp a dimmer is required. Maybe you already have a dimmer in the home for your current lighting. Usually, these are used to dim halogen and incandescent lamps. Each dimmer operates on a certain power, usually 40-08W. If you replace your halogen or incandescent lamps with LED lights, the total power will be lower than the dimmer power. This means that the dimmer does not dim properly, or the light flickers. If your LEDs do not work with a regular dimmer, use an LED dimmer of 0-150W, as + – 85% of the LEDs work in combination with these.

Can you dim a lamp without dimmer?

Thanks to today’s technology it is now also possible to dim a lamp without having a dimmer.


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