The world of science is full of acronyms. One of the more well-known acronyms is the word "LASER," which stands for Light Amplification by Simulated Emission of Radiation. Light particles (photons) oscillate, or move back and forth, through space at some frequency, or number of oscillations per unit of time. Laser light is different from normal light because it is made of photons of a single frequency that are also organized in the way they are emitted: lasers produce a narrow beam of a single frequency of light.

In order to focus create a laser, one must be able to manipulate the frequency and direction of photons in a precise manner. This requires a strictly controlled optical cavity built with specially made materials.

Once you are able to generate laser beams, you can manipulate them for many practical uses. Lasers are found in places that you might not realize. Products like CD and DVD players rely on lasers to detect the patterns of data found on the silicon surfaces of CD and DVD media. Since the speed of light is a constant 186,000 meters per second, lasers can be used as a very precise measuring tool in fields like particle physics and astronomy. They are also used in law enforcement devices to measure traffic speed quickly and at great distances. Called LIDAR (Light Detection And Ranging) devices, these machines generate low-power laser pulses that reflect off moving vehicles and back to the device. The device then determines the distance and speed of the targeted vehicle. The ability to generate extremely powerful lasers has also led to the development of new weapons and cutting tools.

To learn more about lasers, check out Get Close to a Nuclear Fission Reaction!.

To learn about how light particles travel, check out Light Particles Acting Like Waves: The Uncertainty Principle.

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