Light transmission of optical glass Light transmission is the ability of optical glass or optical systems to "let through" as many light rays as possible. The light transmission of a good or powerful riflescope should be greater than 90 per cent. The transmission performance or transmission loss of optical devices such as binoculars and riflescopes, etc. depends heavily on the optical coating of the prisms or lenses. Another important factor for the level of transmission loss, [...]