Part 5 - What is LED?

LED, short for Light Emitting Diode, is a semiconductor device that emits light when electricity flows through it.
LEDs have a different mechanism than traditional incandescent or fluorescent light bulbs.

The biggest feature of LEDs is their high energy efficiency.
Conventional light bulbs lose a lot of energy as heat when emitting light, but LEDs emit light with almost no heat.
Therefore, LEDs require less power to achieve the same brightness, dramatically lowering energy consumption.

Additionally, LEDs have a long lifespan and last longer compared to regular lighting.
The lifespan of LEDs [*] is said to be approximately 50,000 hours or more, which is several dozen times longer than the lifespan of a typical incandescent light bulb.
This reduces the frequency of replacing LED lights and significantly reduces maintenance costs.

LED lights are equipped with dimming and color toning functions, allowing you to choose from a variety of colors and brightness.
In addition, because it is small and has a high degree of freedom in design, it is characterized by a wide variety of lighting equipment.

We can expect further technological innovations in the future, leading to more efficient and sustainable lighting.

[*] Lifespan: When lit under the conditions specified by the lighting equipment manufacturer, the total lighting time until the LED module stops lighting, or the total lighting time until the total luminous flux falls to 70% of the value measured at the beginning of lighting. Whichever shorter time is estimated.

Mechanism and principle of LED

LEDs are semiconductor devices that emit light. I will briefly explain its mechanism and principle.


LEDs are mainly composed of three layers.
There are conductive layers called P-type layer and N-type layer, which have different electronic properties.
The P-type layer lacks electrons, and the N-type layer has a surplus of electrons. The part where these two layers join is called the P-N junction layer.
The principle behind LEDs is that electrons and holes combine in this P-N junction layer, and energy is released in the process.

Additionally, the color of the LED's emission is controlled by the type of semiconductor material and additives.
By combining different materials and additives, a wide range of colors such as red, green, and blue can be achieved.

Three characteristics that make LED innovative

LEDs are revolutionizing the lighting industry.
Let's take a look at how LEDs are superior in terms of efficiency, sustainability, and design.

[Efficiency]

LED is an innovative lighting technology that boasts greater energy efficiency than traditional lighting.
LEDs don't waste much energy when converting electricity to light.
One of the reasons LEDs are so energy efficient is that they generate very little heat when producing light.
In general incandescent light bulbs, a lot of power is dissipated as heat at the same time as the light is emitted, but LEDs efficiently convert electricity into light, so most of the power is converted into light.

Incandescent light bulbs dissipate more than 80% of their heat energy and produce only a small amount of light.
On the other hand, LEDs convert more than 90% of their power into light, so they waste less energy.
It has high luminous efficiency and can produce bright light with little electricity.

This has resulted in reduced power consumption and reduced environmental impact.
Compared to traditional lighting, LEDs can save up to 80% more power.
High light efficiency and effective light distribution ensure you get the brightness you need while minimizing power consumption.

The latest LED technology is opening up the future of sustainable lighting, offering more attractive and effective lighting solutions.

Additionally, LED lights have a long lifespan and provide sustainable energy efficiency.
Typical LEDs have a lifespan of tens of thousands of hours or more, which is several times longer than traditional lighting.
This reduces the frequency of replacing LED lights and significantly reduces maintenance costs.

Additionally, LEDs allow for effective light distribution.
LEDs are directional, meaning they can focus their light in a specific direction.
This property allows light to be delivered efficiently where it is needed.
For example, LED desk lights were originally prone to creating multiple shadows due to their directivity, but as technology has advanced recently, multiple shadows are less likely to occur, and LEDs have become mainstream in desk lights.

[Persistence]

LEDs are also superior in terms of sustainability.
Unlike incandescent and fluorescent bulbs, which experience light degradation over time, LEDs maintain a constant brightness (up to 70% of their initial brightness) until near the end of their lifespan.
The average lifespan of an incandescent light bulb is about 1,000 hours, and that of a fluorescent light is about 10,000 hours, but LEDs generally have a long lifespan of over 50,000 hours.

LEDs have a longer lifespan than incandescent or fluorescent lights, so they need to be replaced less often.
This reduces the frequency of replacement and maintenance, significantly reducing costs.
Additionally, it is expected to contribute to a sustainable society as it emits less CO2 and produces less waste.
The reason why LED is said to be a revolutionary technology is that it not only reduces energy costs, but also reduces the burden on the global environment.

[Designability]

LEDs are attracting attention as an innovative light source due to their compact and thin design.
LEDs are used in a variety of applications due to their characteristics, and their small and thin designs offer many benefits.

First, LEDs allow for very compact sizes compared to traditional lighting technologies.
This makes it easy to integrate into tight spaces and slim designs.
For example, it is used as a small but powerful light source in a variety of products, including lighting for smartphone and tablet displays and car headlights.

The low-profile design of LEDs also provides significant benefits for decorative purposes and for use in certain environments.
As a thin light source, it is often incorporated into building exteriors and interior lighting designs.
By combining it with flexible materials, it can flexibly respond to curves and complex shapes.
This makes it possible to create attractive lighting effects for store displays and indoor design elements.

The compact and thin design of LEDs enables their innovative use in a wide variety of application areas.
The compact size and thin profile give designers and product developers more freedom to think.

summary

The increased energy efficiency and energy savings of LEDs have important implications for the environment.
Lower electricity consumption reduces greenhouse gas emissions and helps mitigate climate change.
Reducing energy consumption also leads to a reduction in electricity demand, contributing to the stabilization of energy supply.

The efficiency, sustainability, and design of LEDs have also revolutionized the lighting industry.
It's safe to say that LEDs promise a bright future, with energy savings and environmental benefits, long lifespans and reduced maintenance costs, a wide variety of benefits, and an expanding range of applications.




Written by: BARREL Editorial Department
Supervised by: Yuki Oe (Lecturer, Department of Lifestyle Design, Faculty of Human Culture, University of Shiga Prefecture)
Lecturer at the University of Shiga Prefecture, Faculty of Human Culture (Department of Lifestyle Design).
She specializes in architectural environments, light environments, lighting environments, and color environments.
She is a member of the Architectural Institute of Japan/Illumination Institute of Japan.
After completing her doctoral course at Nara Women's University Graduate School of Humanities, she worked in technology planning at Sharp.
She worked as an assistant professor in the Faculty of Science and Technology at Tokyo University of Science and as a part-time lecturer at Osaka Jonan Women's Junior College before reaching her current position.