You're looking at over 1 million mirrors. Think about that.
This is the entire headlight unit, and for the sake of scale, assume that pen is of normal size. More than a million mirrors focus the light of over 8,000 individual LED chips, which is how the headlight can selectively leave specified objects in the dark.
As for when you'll see these incredible headlights on the road, Mercedes is a little tight-lipped on that one. The prototypes are already fitted to several cars right now, so it's safe to assume the first cars to feature the production version of the lights will debut in the next year or so.