Richard Feynman’s 1959 lecture “There’s plenty of room at the bottom” envisioned atomic pick and place to build complex nanoscale machines. The lecture is often considered the conceptual birth of nanotechnology.
I am sure this is not the first time conductive AFM has been used to achieve nanoscale patterning to build a useful piece of tech, but very cool nonetheless.
Amazing that this can be achieved at such a low cost. The DVD optical pickup is truly a marvel of engineering, incorporating fairly complicated optics into such a small space. The focusing lens additionally has a electromagnetically controlled suspension system for adjusting the focus, so in theory you should be able to achieve z positioning of the microspheres as well. It would be great if the red dvd laser could be filtered out and the microscopic fluctuations of the trapped particle could be imaged with the camera to estimate the trap stiffness.
A similar optical pickup made of optical components from newport or thorlabs would run you a few thousand dollars, whereas these dvd optical pickups can be had for $10-20.
Here is another great paper (and accompanying youtube video) that shows optical trapping, atomic force microscopy, and even imaging with a dvd optical pickup.
what about computational methods? i have always wondered how stacking many short exposures without tracking compares to deconvolution of a single long exposure. it seems that there is software able to do this by taking into account both motion blur and the PSF of the imaging system:
this paper came out a few years ago using super resolution fluorescence and dna origami to track unwinding of dna by single helicase enzymes! its not an easy technique but it is doable with the right equipment (the 2014 Nobel Prize in chemistry was for super resolution microscopy)
I am sure this is not the first time conductive AFM has been used to achieve nanoscale patterning to build a useful piece of tech, but very cool nonetheless.
https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf