OK, there is more to RF spectrum than just 802.11b (well, lets call it microwave to encompass all the frequency ranges that have issues with water absorption and going through walls ofr any great distance)
an alternate approach might be tick a different part of the spectrum or wait for UWB devices to become available...
however, another way might be to stencil a wireless antennae onto a window. for example fractal antennaes are available with a very small foot print. The idea would be to stencil an appropriate antenna shape onto a window with conductive media (seveal conductive paints are available) or to buy a fractal antenna of the guys linked above (after all, you wouldn't want to infringe their patent would you?)
I have to say I agree. "Nothing to see here, move along." (sorry, bad pun alert)
Basically, it's all about grain boundaries, relative refractive indicies and strength versus toughness. alumina is very strong (able to resist force), but not neccessarily very tough (able to survive damage). The classic Mat eng way to toughen AND strengthen a material is to reduce the grain size. Make the grain size too small to interact with visible light ( 0.4 microns) and you have transparent materials. Well, alright, sometimes. Other things get in the way too, but basically anything that is translucent as large relatively pure cryatals will also be clear as a super fine crystalline solid. Bulk properties and surface properties also count. Which is why it won't work with Al metal. translucent alumina tubing (as used in furnaces) has been around for a long time. - in that case it is usually quite large xrystals. The principal described for transparent concrete seems basically the same. Also, glass-ceramics (Dow Arcosteel (?)) is dasically the same principal. I wonder how they are doing it? Are there any Al2O3 rich glasses that could be converted to Al2O3 by heat treatment? Has anyone tried this with Geopolymer?
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why not just use seethrough solar panels? (see www.sta.com.au) - DSC dye-sublimation solar collectors are cool!
OK, there is more to RF spectrum than just 802.11b (well, lets call it microwave to encompass all the frequency ranges that have issues with water absorption and going through walls ofr any great distance)
an alternate approach might be tick a different part of the spectrum or wait for UWB devices to become available...
however, another way might be to stencil a wireless antennae onto a window. for example fractal antennaes are available with a very small foot print. The idea would be to stencil an appropriate antenna shape onto a window with conductive media (seveal conductive paints are available) or to buy a fractal antenna of the guys linked above (after all, you wouldn't want to infringe their patent would you?)
I have to say I agree. "Nothing to see here, move along." (sorry, bad pun alert)
Basically, it's all about grain boundaries, relative refractive indicies and strength versus toughness. alumina is very strong (able to resist force), but not neccessarily very tough (able to survive damage). The classic Mat eng way to toughen AND strengthen a material is to reduce the grain size. Make the grain size too small to interact with visible light ( 0.4 microns) and you have transparent materials. Well, alright, sometimes. Other things get in the way too, but basically anything that is translucent as large relatively pure cryatals will also be clear as a super fine crystalline solid. Bulk properties and surface properties also count. Which is why it won't work with Al metal.
translucent alumina tubing (as used in furnaces) has been around for a long time. - in that case it is usually quite large xrystals.
The principal described for transparent concrete seems basically the same. Also, glass-ceramics (Dow Arcosteel (?)) is dasically the same principal. I wonder how they are doing it? Are there any Al2O3 rich glasses that could be converted to Al2O3 by heat treatment? Has anyone tried this with Geopolymer?