Glass windows

--- In spacesettlers, joe wrote:

> There are severe efficiency losses for this approach, however. On
> Earth this is being used to retrofit some buildings with natural
> lighting -- but only on the top floor. For the next floor down, the
> losses are so large that it's no longer worth it. Or so I have read
> (though I haven't been able to find the reference, I think it was in
> Technology Review within the last few months).
>
> Best,
> - Joe

That is a serious concern. So much for putting the collectors on an
end-cap. It still might work if the collectors were on the outside of
the cylinder proper.

The guys in Israel didn't use a laser, it was sunlight. The whole
idea was find something cheaper than lasers.

I guess if you make the whole thing out of sapphire, you could just
leave the window areas unpainted. Windows again. Surely they don't
have to take up half your area?

For the Israeli sunlight stuff:
http://www.findarticles.com/p/articles/mi_m1200/is_14_162/ai_93205218