This is an example of fritted glass as used in windows at the downtown branch of the Minneapolis Public Library. The pane on the right contains the elements which make the glass visible, and/or the interior of the building less visible. Light does pass through this glass. The pane on the left is normal window glass, showing the reflection common in certain situations. Birders have requested the Minnesota Vikings to use fritted glass in the stadium under construction in an effort to lessen collisions by birds with exterior stadium glass, some 200,000 square feet of it. The photo is of the only fritted glass I could locate locally, with modest effort. I don't know the degree to which this example contains the fritting material -- high degree, medium, or low. It does, however, show how fritting can appear. It certainly shows why birds would be less likely to collide with the pane on the right versus the pane on the left, and, if vision through the glass is desired, it shows why fritting, at least to this extent, might not be chosen.