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Photonics

physical science Maturity 7-9 Next article →

Photonics is a branch of science that studies light. It focuses on how we make, find, and move light. This light is made of tiny bits called photons.

Aphrodita aculeata (Sea mouse)
Aphrodita aculeata (Sea mouse)

Scientists use photonics to do many different jobs. These jobs include sending signals or sensing the world around us. Most work happens with visible light or near-infrared light. This is the light we can see or that is very close to it. Photonics is a very big field with many uses.

How does photonics work in steps? First, a light source creates photons. We use things like LEDs or lasers to do this. Next, the light travels through a medium. Glass or plastic fibers can guide the light along a path. Sometimes the light signal gets weak during its trip. An amplifier, like an erbium-doped fiber amplifier, makes the signal stronger. Finally, a detector catches the light. Photodetectors, such as those in digital cameras, turn the light back into information.

People have been studying light for a long time. This is called classical optics. In 1905, Albert Einstein explained how light works using the photoelectric effect. The specific word "photonics" appeared later in the 1960s. A man named John W. Campbell even suggested the name in a 1954 letter. He said photonics is to optics what electronics is to electrical engineering. By the 1980s, the term became very common. This happened as companies started using fiber-optic cables for data.

There are many important facts about this science. The word comes from the Greek word "phos," which means light. In the 1970s, scientists developed optical fibers for sending information. These fibers helped build the infrastructure for the Internet. Many tools use photonics every single day. A barcode scanner uses light to read labels. Remote controls use light to talk to a TV. Even solar cells use light to collect energy for our homes.

Photonics connects to many things you already know. You might use a laser printer to print school papers. You likely use a CD or Blu-ray player to watch movies. Doctors even use lasers for eye surgery or to fix vision. In factories, lasers are used for welding and cutting metal. Even in the military, sensors use light to help with search and rescue. This science is everywhere in our modern world.

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