Light transmitting concrete
Three years ago, Hungarian architect �ron Losonczi invented LiTraCon, the first light transmitting concrete.
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A wall made of LitraCon has the strength of traditional concrete but thanks to an embedded array of optical glass fibers, view of the outside world, such as the silhouette of trees, houses and passersby, are transmitted inside the building.
The wall can be quite thick as the fibers work without any loss in light up to 20 m.http://www.we-make-money-not-art.com/archives/003654.php