3 ms·

A rough ASCII sketch to illustrate this: Regular lens: _____ / \ / \ Fresnel lens: _____ /|/ \|\

• anc84 7y ago
  That does not work at all and just confused me. The angles must change on the interrupted parts to follow the general curve of the lens' surface. https://commons.wikimedia.org/wiki/File:Fresnel_lens.svg https://commons.wikimedia.org/wiki/File:Fresnel_lens.svg is a very good illustration.
  • crottypeter 7y ago
    As a counterpoint the GPs diagram was useful for me (perhaps because I have a background involving some study of optics). Granted the parents picture is way better than the rough ASCIIart