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Science_Lab_Yellow / Lesson 8: How Do Lenses Work

How Do Lenses Work

What will we be learning today?

  • In this lesson, we are going to learn all about how lenses work.

  • How Do Lenses Work?

    Lenses are pieces of transparent materials with curved surfaces that use the refraction of light to make images. Convex lenses curve outward, while concave lenses curve inward. The diagrams on the next couple slides show how these lenses form images.




    Convex lenses form images by refracting light rays together. The size and position of the image depend on how far the object is from the lens.



    Concave lenses form images by refracting light rays apart. These images are always right-side up and smaller than the object.




    Telescope have convex lenses



    Binoculars work like a pair of small telescopes-one for each eye. They are used for viewing distant objects. Unlike most telescopes, binoculars give an enlarged, right-side-up view.



    Lenses used in microscopes help you see a tiny world that is invisible to your unaided eye.


    Let's Review What We Learned Today!

  • Convex Lenses - bulge outward at the middle (form images by refracting light rays

  • together - size and position of the image depend on how far the object is from the lens)

  • Concave Lenses - "cave in" in the middle (form images by refracting light rays apart - images are always right-side up and smaller than the object)

  • Different lenses are used in telescopes, binoculars and microscopes