Activity 3


 
The Fresnel Lens


Introduction

Your task: determine if this "Fresnel" lens in your Optics Kit will behave the same as a regular lens.

Procedure

  • Gather these items from your Optics Kit:
    • a Fresnel lens (the flat, ridged lens)
    • Lenses A and B

  • Compare the Fresnel lens to Lens A and B. How is a Fresnel lens similar to a "regular" lens? How is it different?

  • Feel the surface of the Fresnel lens. What do you notice? Make a sketch in your notebook of how you think the surface might look up close.

  • See the previous Activity, Lenses, and follow the instructions for measuring the focal length and magnification of your Fresnel lens.



  • How does the magnification of the Fresnel lens compare to that of the other lenses? Is its focal length shorter or longer than the other lenses?

  • Can you find a practical use of a Fresnel lens in cars, flashlights, camping lanterns...?

To read more about Fresnel lenses, go to the Fresnel Lens Readings



Page authored by ACEPT W3 Group
Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1504
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