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General Science => General Science => Topic started by: thedoc on 29/11/2011 15:11:11

Title: How could you design a lensless microscope?
Post by: thedoc on 29/11/2011 15:11:11

Changhuei Yang explains his design for a lensless microscope...
Read a transcript of the interview by clicking here (http://www.thenakedscientists.com/HTML/content/interviews/interview/1877/)

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Title: How could you design a lensless microscope?
Post by: CliffordK on 01/12/2011 09:29:33

Interesting.
Interpolated resolution by moving the light source.

What about a time delay?  Lots of pixels would be an advantage, & great for looking at static stained slides.

However, if it takes... say 5 seconds to take an image, then it would be difficult to get a good image of living tissue like one gets when looking at a drop of pond water.

They also don't really list the interpolated resolution. 
The average eukaryote cell may be 10 microns, so 4 microns would allow it to be visualized, but with limited detail.
The average prokaryote cell is about 2 microns...  so that would give you about 4 cells per pixel.  Not too good.

Of course, technology will improve over time.

A traditional light microscope is limited to about 0.2 microns, or about 1/20^th of the non interpolated lensless microscope above, but some techniques push them down into the nanometer range.

Perhaps there is a way to merge some of the technologies.

Title: How could you design a lensless microscope?
Post by: syhprum on 01/12/2011 19:04:52

Any scanner that examines an image thru a small aperture can be regarded as a lensless microsope, with a sufficiently bright light source and a small enough aperture resolution of less than the wavelength of the light used can be achieved.
An early use was the Farnsworth image dissector used by J L Baird in his early 240 line TV transmissions from Alexander Palace.