You See Nanoscale Differences, and You Didn't Even Know It

In a paper published in the Optical Society’s Optica, a research team from the University of Stuttgart and the University of Eastern Finland has harnessed the human eye’s color-sensing strengths to give the eye the ability to distinguish between objects that differ in thickness by no more than a few nanometers — about the thickness of a cell membrane or an individual virus. This ability to go beyond the diffraction limit of the human eye was demonstrated by teaching a small group of volunteers to identify the remarkably subtle color differences in light that has passed through thin films of titanium dioxide under highly controlled and precise lighting conditions, according to the press release.The result was a remarkably consistent series of tests that revealed a hitherto untapped potential, one that rivals sophisticated optics tools that can measure such minute thicknesses, such as ellipsometry.Read more.