Laser

Laser is a type of light that is very different from ordinary light and capable of amazing feats! For example, it can cut through thick metals, measure distances in space, and even assist doctors during surgery. So how does laser become so special? Let’s learn step by step!

What Is Laser and Why Is It Special?

Laser is an acronym for Light Amplification by Stimulated Emission of Radiation. In simple terms, laser light produces a highly ordered, bright and powerful beam, unlike ordinary light. Normal light, such as from a bulb or the sun, is a mixture of different colors and directions. Laser light, however, travels in a single color, in one direction, and in perfect alignment. This is why it appears like a thin line and can travel extremely long distances!

Laser light does not occur naturally. Scientists produce laser light using special devices. Unlike a flashlight, which spreads light in all directions, laser light remains focused and intense. This property makes lasers an exceptional tool in many fields!

How Does Laser Work?

To produce laser light, scientists use photons, the smallest particles of light. Photons are packets of light energy. To create a laser, energy is first applied to a material such as a gas or crystal. This energy excites the electrons inside the material to higher energy levels. This process is called pumping.

Then, a beam of light is directed at these excited electrons. This light triggers the electrons to release new photons with identical properties. These newly emitted photons form the laser light! To amplify this light, two mirrors are used. The mirrors reflect the light back and forth, and with each reflection, the light becomes stronger. Eventually, a portion of this powerful light escapes through one of the mirrors, forming the laser beam.

This process essentially clones or copies the light, which is why laser light is so uniform and coherent. It is as if a whole army of light particles is marching in perfect unison in a single direction!

Where Are Lasers Used?

Lasers appear in many areas of daily life and science. Here are some examples:

• Medicine: Doctors use lasers for precise surgeries, such as eye operations.
• Technology: DVD players, barcode scanners and laser printers operate using laser light.
• Communication: Internet and television signals are transmitted rapidly thanks to lasers.
• Science: Lasers are used to map the surfaces of planets in space or to analyze the composition of rocks on Mars. For example, NASA’s Curiosity rover uses a laser to study rocks on Mars!
• Distance Measurement: Scientists can measure the distance between the Moon and Earth using lasers. A laser beam is sent to the Moon, reflects back, and the time taken for the round trip is measured to calculate the distance.
• Industry: Lasers are used to cut thick metals or diamonds.

Types of Lasers

Lasers come in different types depending on their size and how they operate. Some are very small, while others are as large as a table! For example:

• Solid, gas or semiconductor lasers: These are named based on the material used to generate the light.
• Continuous or pulsed lasers: These differ based on whether the light is emitted continuously or in short bursts.

The Future of Lasers

Lasers will become even more important in the future! They will be especially crucial in super-advanced technologies such as quantum computers. Perhaps one day, lasers will enable us to travel to even more distant planets in space!

Where have you seen lasers? Maybe in a barcode scanner or a science fiction movie? Lasers are everywhere!