A digital camera the size of a grain of salt
Toronto. Science seems to vacillate between analogue and digital concepts. The earliest radio receivers used digital – a “cat’s whisker” and a speck of solid state material.
Significant improvement occurred when technology shifted to analogue – vacuum tubes – then later last century back to digital again.
Similarly but on a much longer time scale, photography was initially analogue (films, glass plates, tintypes, daguerreotypes, salted paper) and then late last century and early this century, digital – with sensors getting smaller and denser raising both sensitivity and resolution.
The earliest photographic lenses too were analogue creating a very tight bundle of light. Multiple lens elements of different glass types and curves corrected distortion and created a flatness of field. Microscope objectives used tiny lenses – the diameter falling as the magnification increased and the NA – numeric aperture – decreased. But always with a great many elements – even more than in a photographic lens, especially as objective magnification and NA both increased.
Now (Monday, Nov 29, 2021) the Scientist Study web site reports results by researchers at Princeton University and the University of Washington that demonstrates a camera and lens the size of a grain of salt. The key to the design was creating a lens that reacted to light in a digital fashion! The result infers much higher resolution and smaller physical size than earlier devices offered.
The last colonoscopy I had, my surgeon offered a tiny camera in a pill capable of spotting a polyp about 5mm in size. Learning that the same pre-procedure cleansing process was used and any polyp discovered would need a colonoscopy anyway to remove it, I declined the pill since the cleansing was always the most onerous part of the procedure. Now a grain of salt size camera with higher resolution makes it time to reconsider ,,,,
My thanks to my friend Russ Forfar, deep in the wilds of southwestern Ontario, for suggesting this post and offering the above links.
