I love these descriptions of how flat and regular the Zeiss mirrors need to be for ASML EUV lithography.
The accuracy required would allow you to shoot a golf ball on the moon with a laser.
Or put differently, if you were to extend the mirror over the size of Germany, the imperfection would be at most 20 micrometer, thinner than hair.
https://bookwyrm.social/user/fj/quotation/6797524
