Scientists at Harvard University have come up with a way of making tiny, high resolution flat lenses that work within the visible spectrum. The advancement may have major consequences for endoscopy, surgical microscopy, and other clinical and pre-clinical technologies that can benefit from smaller, high quality lenses.
Closeup of titanium dioxide nanofins on a glass substrate
Unlike conventional lenses that are shaped pieces of glass or other material, Harvard’s “metalenses” are actually nano-scale constructs made of titanium dioxide that force light to travel so as to replicate a real lens. This has allowed the team to use the lens to actually resolve objects smaller than the wavelength of light.
There are certainly limitations to the technology and these are not exactly direct replacement for wide spectrum lenses, as each has to be made for a specific frequency of light.
Here’s a computer simulation showing the functionality of the new lenses followed by a Harvard podcast discussing the technology:
Study in Science: Metalenses at visible wavelengths: Diffraction-limited focusing and subwavelength resolution imaging…
Via: Harvard Gazette…