Just had an elderly gentleman come in to tell me that when he is riding the Sky Train his vision is clearer when looking through the windows of the Sky Train. He has repeated this test numerous times and finds an improvement with or without his glasses on. This effect does not happen through regular windows only through thick glass.

From a sky train tech I know came this reply "All I can tell you it is thick glass and double vacuum sealed. Some are tinted and they all have a thick plastic on them called “Vandal Shield”.

Would anyone be able to advise me how to duplicate this effect with spectacle lenses?