For example, by making the pitch smaller than the wavelength, form bi-refringence can be achieved and pixilated polarization imagers can be created as well as wafer scale retarders. Yet another application is the creation of moth's eye" type anti-reflection surface structures eliminating the need for antireflective coatings.
Wire grid and pixilated wire grid polarizers
Pixilated polarization imagers
Anti-reflection surfaces without the need for AR coatings
DIRECCION WEB: http://www.memsoptical.com/prodserv/products/finepitch.htm