|
The process is one which utilizes a vacuum chamber.
The lens is first cleaned. A base coat of clear lacquer is applied to the lens surface. After curing, the lens is placed is a vacuum chamber which is then pumped down to a few microns of pressure. When the chamber is fully evacuated, heating elements built into the bottom of the chamber are activated heating several small ribbons of pure aluminum. Because the metal is in an atmosphere considerably below its vapor pressure it sublimates directly to a gas. The gas distributes itself uniformly through out the chamber, coating (changes phase) everything including the lens with a very shinny coating of aluminum. Vacuum is released, the vessel returns to atmospheric and the lens is removed.
Because this coating is extremely thin and fragile, another coating of clear lacquer is applied for protection.
The lens appears to have been chrome plated. Nope, just aluminum.
There is another process for electroplating plastic with real chrome, but that's another story.
Gary Kitterman
'56 C-73 "Babe"
|
Back to the Home of the Forward Look Network