What They Say
Researchers from Cornell’s School of Applied and Engineering Physics and Samsung’s SAIT have made a new metalens that can be focused using voltage instead of mechanically moving its components. Metalenses are flat arrays of nano-antennas or resonators, less than a micron thick, that act as focusing devices. But until now, once a metalens was fabricated, its focal length was hard to change, according to Melissa Bosch, doctoral student and first author of a paper detailing the research in the American Chemical Society’s journal Nano Letters.
The new idea uses liquid crystals to tailor the local phase response of the metalens and a voltage-actuated metalens with continuous zoom and up to 20% total focal shift was reported. The group fabricated a bifocal metalens that facilitates high-contrast switching between two discrete focal lengths upon application of a 9.8 Vpp voltage bias.
At the moment, the lens only works on a single wavelength of red, but the group is working on developing full spectrum lenses.
What We Think
This is Intriguing, but single wavelength optics and multi-wavelength optics can be very different. This is definitely in the R part of R&D. (BR)
