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Diffraction Limit Sample for Microscope

  1. Mar 29, 2013 #1
    Hi all,

    So, I'm trying to "hit" the diffraction limit (i.e. view Rayleigh criterion, or Abbe or Sparrow criterion) with my light microscope . Bought the scope off amazon..it's a typical AmScope that has 2000x magnification limit.... But the trouble is I can't find a good sample of two spots.

    I used my OLED screen on my phone...but the pixels are 85 microns apart...which my microscope can easily resolve.

    Then I turned to MEMS Microsphones http://memsjournal.typepad.com/.a/6a00d8345225f869e20147e315f8a1970b-pi

    which i have a few samples of...the perforation holes are 10.5 microns in diatemer, separated by approx 5.56 microns. My scope can easily resolve them.

    Preparing two small holes 100-600nm apart from one another would be likely too difficult for me to create.

    any ideas on how to view Diffraction Limit, or rayleighs criterion, etc?

    I was thinking maybe slides created for Two Slits Interference experiments.

    Thank you,
  2. jcsd
  3. Mar 29, 2013 #2

    Andy Resnick

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    What's the numerical aperture of your lens?

    Something simple to try: swab the inside of your cheek with a q-tip, and wipe the q-tip on a slide. Add a drop of water, cover with a coverslip, and you'll have hundreds of epithelial cells to look at, full of objects below the diffraction limit. Other objects: diatoms, microspheres, soot.
  4. Mar 29, 2013 #3
    NA = .1 though I have other lens.

    These are the lens i have: http://ecx.images-amazon.com/images/I/51SnU8iFrNL.jpg

    the red one on the right is .1, I can vary from there.

    Re the Epithelial cells: so the cells themselves are sub-diffraction limit? Or the things inside them are?

    Thank you for your reply.
  5. Mar 29, 2013 #4

    Andy Resnick

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    The things inside- your set of lenses are well-suited for looking at cells, either from your mouth or from plants- try peeling off a thin layer from an onion, for example.
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