"Richard J Kinch" wrote in message
. ..
Dave writes:

How clear is it and would it be OK to use in front of a window?

Expensive. Ages rapidly in sunlight. Susceptible to many oils and
solvents.

Rich is right on. There *are* ploycarbonate sheets with UV filtering
coatings. This must face outside to protect the sheet. Polycarbonate has a
soft surface and will scratch easy. This may be a concern if clarity is an
issue.

Why not use acrylic? While polycarbonate is the toughest, acrylic still has
many times the impact strength of glass, it is much lower cost and it won't
haze over in the sunlight. While it scratches easier than glass it is less
suseptable to hazing due to fine surface scratches than polycarbonate.

John