Daylighting is more a factor of window geometry and orientation. The 1930s model schools in the USA all had day lighing requirements. This resulted in classrooms with long narrow windows and high ceilings to get daylight to cover the room.
A 24’ x 30’ classroom would have 10’ ceilings with 7’ windows starting around 3’ off the floor. These windows would be on one wall and make up around 40% of the wall.
Thank you for this - the article had me wondering: if they are putting the PMMM film over glass, what's the point? - any extra transparency from the film will just be negated by the glass, but in the paper it appears they have developed a PMMM panel that they used in testing.
The film doesn't create extra transparency, just the opposite, it's a diffuser, it's translucent. It lets light through, but details aren't visible through it. The interesting parts are the radiant cooling and the self-cleaning. However, it's just a thin film, so it needs a substrate like glass to be practically useful.
Can you de-frost it with glucose syrup or honey the way I was shown on a TV science show you can de-frost normal frosted glass? (the refractive index is close enough)
Probably. The effect seems to depend on light interacting with textural surfaces of the PMMM material. If those surfaces are surrounded with a fluid having the same refractive index, the surfaces will disappear as far as first-order optical interactions go.
Glucose syrup or honey or any liquid other than maybe accidentally splashing it with water isn't exactly "casual viewing", and water presumably won't work since it's a "superhydrophobic surface".
Wow, this sounds pretty nice. I remember watching a MedCram video recently that pointed out that long wave IR light has anti-inflammatory properties and that modern IR blocking glass is actually depriving people of many of the beneficial effects of sunlight. If this could get people more IR, it could raise the bar for health across the board. Still, I have some concerns. It's a polymer nanomaterial, so it's probably fairly fragile. The "self cleaning" part is just that it's hydrophobic, which is nice but relies on the nanostructure. Again, probably susceptible to damage. The chemical itself, poly-dimethylsiloxane is pretty common but it appears that they're forming the nanostructures using a mould made via silicon lithography? That's not going to scale at all, nor does the coating seem durable enough for decades of outdoor use.
I only skimmed the paper so please correct me if I'm wrong but this is very far from production-ready.
AFAIK IR blocking film is fairly recent development. In NZ it's only past year when it became required for all new buildings (helps with reducing heating and cooling costs).
Most glass blocks UV tho which makes some marketing shady.
I can't comment on the manufacturing process, but in terms of durability -- would probably just put this in between two panes of glass in a double pane window?
Doesn't that entirely defeat the purpose of this new glass letting in more light than new glass? Or would the outside panes be made of the new glass without the nano structure?
The new material is an extremely thin film that sits on top of a traditional glass substrate: it doesn’t replace the window, and it doesn’t dim light or reduce the spectrum in the same way that frosted glass normally would.
That doesn't really meet the needs of my particular application. I want to let as much light through as possible, just scatter it a bit, but that privacy film stuff reflects quite a lot of light.
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[ 5.5 ms ] story [ 44.0 ms ] threadAlmost everyone I know agrees that classical style building are more beautiful to look at, but all that beautiful stone doesn't let in too much light.
Now we might have materials that allow us to build with a more interesting esthetic and still allow as much natural light as possible.
A 24’ x 30’ classroom would have 10’ ceilings with 7’ windows starting around 3’ off the floor. These windows would be on one wall and make up around 40% of the wall.
But yeah, it's not a security tool.
I only skimmed the paper so please correct me if I'm wrong but this is very far from production-ready.
https://www.sciencedirect.com/science/article/pii/S101113442...
Most glass blocks UV tho which makes some marketing shady.
This is why a window tint probably isn't a good idea for your home.. outside observers can see right in at night when a light is on.
If this Frosty glass performs like regular frosted glass in the dark, that'll be amaze!