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.

 

[sardar]

I would suggest using a sample with a pattern that has a known distance between the features, such as a resolution test target or a grating slide. These types of samples are specifically designed for testing the limits of microscope resolution and can help you accurately determine the diffraction limit of your microscope. Additionally, using a high-quality objective lens and optimizing your microscope's settings can also improve your ability to resolve smaller features. If creating your own sample with small holes is too difficult, these other options may be more feasible and reliable for testing the diffraction limit of your microscope.