Diffraction Limit Sample for Microscope

[entropy111]

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,

 

[Andy Resnick]

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.

 

[entropy111]

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.

 

[Andy Resnick]

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.

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.