[stevenrace]

Simply put, glass is molecularly geometric - building actuated buttons into the glass itself isn't very probable. But a film of actuated buttons could be added much like with capacitive touch sensors today.

Microfluidics is near the 100nm range today. Throw in a bit of ferrofluid and something like this is at least plausible. The challenge is in making all this transparent. The microfluidic channels would need to not create a 'screen door effect' and the fluid transparent.

The Royal Society of Chemistry's 'Lab on Chip' Youtube Channel [1] is a good place to daydream about the future of such things.

[1] http://www.youtube.com/user/labonachipVideos/videos

[reticulated]

You might also find this video [1] interesting. Although it's not clear how far this company has actually got with the technology.

[1] http://vimeo.com/43431035

[stevenrace]

@1m18s you see a syringe of fluid - so it's something similar. Maybe two laser-cut capacitive films with non-conductive fluid pumped through to make static 'buttons'. Probably a better MVP than what I suggested earlier :).

Thanks for the link.

[xerophtye]

If your target audience are the visually impaired, why do you need to make them transparent?