Without Googling it, do you know what it is?
My office had some installed.
It's a glazing film that's put over glass.
Depending on how you place it and which style it is, it can blur from one angle but appear clear looking straight on.
The installers were jerks the whole time and being that they get paid regardless, they couldn't spare so much as an inch for me. Naturally I wanted at least 6" x 3".
Seems very expensive as it's still new but if anyone knows someone in the glazing business, this would seem like a new idea for photo protection.
Problem would be getting it off if ever needed.