[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [ATM] refractive index of air

On Mon, 13 Aug 2007, Bob May wrote:

> The ambiguity came in because a prvious poster in this thread
> mentioned that working on the edge causes the ROC to change.

No problem. I think it is not uncommon for the edge to conform
to a different ROC than the center. I believe by convention, we
use ROC for a sphere determined from the central axis. The
departure from sphere for all other profiles is an off axis
phenomenon. In this case, any single point off axis can conform
to some other sphere, but the curve derived from multiple
off axis points cannot conform to a sphere. It is also
possible to actually have some aberration off axis that is
spherical and has a different ROC than the central axis. That
is usually a surface defect we are trying to remove.

Dominic

_______________________________________________
ATM mailing list http://www.atmlist.net/