Dear Optiboarders,
I , generally ,ask you what is the real meaning to do an AR coating with a monochrome residual reflection.
This morning i saw some lenses with an achromatic residual reflection produced by an European company .The residual reflection was white and the transmittance near 99.3% .
My first think was : " Right , this IS an AR coating".
If we forget for a moment the consequent production troubles that a producer can meet (not so big trouble really) , Why the Optical market promote a modest AR with a monochrome residual reflection without consider the AR coating as AR coating.
Please don't give answer like : "green or other kind of monochrome reflection is something as a label that identify AR coating".


thanks

Mauro Ventura