Re: [APML]: What is Adaptive Optics?

[konomi@mail.geocities.com]

> therefore, I would call this "active" optics and not "adaptive" optics?
> I would think that "adaptive" refers to an actual physical deformation
> of the shape of some imaging surface, while "active" refers to a shift
> in orientation of some refective mirror, like the "adaptive optics"
> (really "active") as offered by SBIG?

There seem to be many definitions being tossed around at the moment 
relating to active and adaptive optics.  While I have at times gotten 
testy with various uses of the words folks use, I have started to 
apply my own loose definition.  If the "system" provides a factor of 
10 improvement in the seeing, ie from 1 arcsecond to 0.1 arcsecond or 
better, I call it a "good adaptive optics" system, if it does not I 
call it a "poor adaptive optics" system.  At this point folks who are 
offering tip/tilt correctors will often point out that there system 
is actually really good for an active optics system. 

One should also worry about strell ratio improvements but that is 
another aspect of the story.

Cheers,

Scott
---------------
Dr. Scott Teare
University of Illinois and Mt. Wilson Observatory
Mt Wilson, California.