Electric light

An electric light, lamp, or light bulb is an electrical device that makes light from electricity. It is the most common way to make lighting when it is dark. These lights usually have a base made of ceramic, metal, glass, or plastic. The base fits into the socket of a light fixture. The light can connect to the socket in different ways, such as a screw-thread base or a bayonet mount.

There are three main types of electric lights. Incandescent lamps work by heating a filament until it glows with electric current. Gas-discharge lamps, like fluorescent lamps, make light through an electric arc in a gas. LED lamps make light when electrons move across a band gap in a semiconductor.

The energy efficiency of electric lighting has gotten much better since the first lights were made in the 19th century. Today, there are many kinds and sizes of modern electric light sources for different uses. Most electric lights use electricity from big power stations, but they can also run on mobile generators or batteries. Battery-powered lights, such as flashlights or electric lanterns, are often used when other lights are not available, like during power outages or when traveling.

History

Before electric lighting became common in the early 20th century, people used candles, gas lights, oil lamps, and fires. In 1799–1800, Alessandro Volta created the voltaic pile, the first electric battery. This led to early experiments with electric lights.

Later inventors improved electric lighting. In 1840, Warren de la Rue made an early electric light bulb using a platinum coil. In the late 1870s and 1880s, Joseph Swan in the UK and Thomas Edison in the US developed practical lamps. By the early 20th century, these had replaced earlier arc lamps. Later came the tungsten filament and the first neon lights. The first practical LED arrived in 1962, and the blue LED in 1994 helped create white LEDs for everyday use.

Types

Main article: Incandescent light bulb

Incandescent light bulbs have a thin coil of tungsten inside a glass bulb. When electricity flows through the tungsten, it heats up and glows, making light. These bulbs are not very energy-efficient because most of the electricity makes heat instead of light. Many places are replacing them with more efficient options like LED bulbs.

Main article: Halogen lamp

Halogen lamps are smaller and brighter than regular incandescent bulbs. They use special glass and gases to make more light with less energy. They also last longer and stay bright for more time.

Main article: Fluorescent lamp

Fluorescent lamps are long, thin tubes that create light using a small amount of mercury and gas. When electricity passes through the tube, the gas glows, and a special coating turns that glow into visible light. These lamps are more energy-efficient than incandescent bulbs but need to be disposed of properly because of the mercury.

Main article: LED lamp

LED, or light-emitting diode, lights are very energy-efficient and can last a long time. They have been used in small devices for years and are now used in many bigger lighting applications. LEDs can turn on and off instantly and don’t produce much heat.

Main article: Arc lamp

Carbon arc lamps were one of the first electric lights. They use two carbon rods that create a bright arc of light when they are brought close together and then pulled apart. These lamps were used for street lighting before being replaced by more modern lights.

Main article: Gas-discharge lamp

Discharge lamps, like neon signs, use gas inside a glass tube to create light. Different gases make different colors. These lamps are very efficient and are often used for street lighting and other large lighting needs. Some types, like low-pressure sodium lamps, produce a strong orange light that helps reduce light pollution.

Characteristics

Many light bulbs come in common shapes and sizes, which makes it easy to pick the right one for different uses. For example, bulbs might be labeled “A19” for their shape and “E26” for the type of base they have. This helps you match the bulb to the right light socket.

When you look at light bulbs, important things to think about include how much light they make (measured in lumens), how much energy they use (measured in watts), and what color the light is (measured in kelvins). Bulbs also have a lifespan, which tells you how many hours they can work before they start to dim or stop working. Some bulbs may last longer or shorter than this time, depending on how they are made and used.

Uses

Electric lamps are not just for lighting; they have many other uses too. For example, they can help plants grow indoors as grow lights, especially in places without natural sunlight like hydroponics systems or for aquatic plants.

They are also used in special ways to help people. Some lamps give off heat and are used in baby incubators or in restaurants. Others are used to help treat health problems like skin conditions or low mood during dark winters.

Cultural symbolism

In Western culture, a lightbulb—especially when it looks like it is lit above someone’s head—shows a sudden idea or inspiration.

A styled light bulb is also used as the logo of the Turkish AK Party.