For what it's worth, you can find a nice detailed description of Microsoft's approach to sub-pixel anti-aliasing in "Optimal Filtering for Patterned Displays" [1]. There is also a follow-on, "Displaced Filtering for Patterned Displays" [2].

Interestingly, both papers feature an aliased zone plate. :-)

[1] http://research.microsoft.com/pubs/68972/optfilt.pdf

[2] http://research.microsoft.com/pubs/68631/sid2000.pdf