Ming Yan

Light can be combed like hair. Instead of hair, we have frequencies; instead of a comb, a laser. The result is a comb made of thousands of even 'teeth'—frequencies. Such an optical comb helps study molecules and measure time with precision down to quadrillionths of a second. An ordinary comb has teeth spaced evenly apart.

A conventional lidar is like an artist who paints a landscape but sees only gray shadows. It measures distances to each point accurately, but can't tell whether it's looking at rock, wood, or plastic. To learn the composition, you need a spectrometer — a separate device that works slowly and can't keep up with a fast scanner. The new system takes a different approach.