Slanted Grating Turns Weak Light into Pure Color
Imagine blinds that don't just block or let through light but change its color. Light hits the slanted stripes, and some rays come out a different shade, as if a white beam, passing through the slits, turned green. That's exactly how this new surface works: on a thin film of lithium niobate (a material that can transform light), there are slanted stripes of titanium dioxide.