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Science_Lab_Yellow / Lesson 8: What are Lasers

What are Lasers

What will we be learning today?

  • In this lesson, we are going to learn about what are lasers.

  • What are Lasers

    You've seen lasers in many places-such as at music events and even the checkout counter at the supermarket. Lasers are devices that produce thin streams of light. What makes light from a laser special?


    What are Lasers

    Regular light from a bulb or a candle has many wavelengths all mixed together. As the light travels away from the bulb or candle, it spreads out and gets less noticeable. It gets weaker and weaker the farther it travels.




    Lasers produce light that does not spread out or become weaker. Lasers, such as this device using a red ruby, produce light by absorbing flashes of light from a coiled tube. Inside the ruby the absorbed light bounces back and forth between mirrors at the ends of the ruby. As a result, the ruby gives off a light of just a few close wavelengths. The wavelengths are all one color and line up "in step." The beam that comes out of the ruby is narrow and direct.











    Lasers are used in astronomy.


  • Now complete your worksheet!