Archived posting to the Leica Users Group, 1997/02/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 07:10 PM 12-02-97 -0500, Marc wrote: >The color of the coating tells us little except as an indicator of what >chemicals were used in the compound. I suggest you contact the Galahad of >expertise on this, John Van Stelten <focalpt@ecentral.com> -- who just did a >superlative job on my 1.5/7.5cm CZJ Biotar in LTM, by the by, received this >day -- for further information. Actually, the colour of the coating tells us the thickness of the coating(s). The colours are caused by intereference of the incoming light waves with light that is reflected back from the various interfaces between coatings, and coatings and glass. Ideally, if the coatings were doing their job, you wouldn't see anything at all reflected back when you looked at a lens. The coatings are intended to match the impedence between air and glass. Dan C.