"Chris L Peterson" wrote in message
...
On Mon, 21 Mar 2005 14:03:07 GMT, Jan Panteltje
wrote:

I have been wondering if somehow fluid lenses could be used for adaptive
optics in a telescope...

The most basic AO correction is for image shift (usually called
tip/tilt). Any system needs to address this, and it isn't obvious how
fluid lenses could do so.

Beyond that, there are many high order corrections. While this can
involve a change in focus, which a variable lens could correct for, the
corrections are typically achieved by altering the wavefront over
multiple zones- something a single lens can't do.

The usual actuator for AO is a flexible mirror, and this is not the
difficult part of the problem. A flexible mirror can be made quite
inexpensively these days, especially if there were some high volume
application.


The flexible mirror, by itself, if useless unless coupled with actuators that
can deform it, a computer to drive the actuators based on some measurements of
the wavefront distortion, and a means to take those measurements. For amateur
use this probably means something quite a bit smaller and far more economical
than what the professionals use. Whether such a device can be made small enough
and economical enough is one question. Whether enough amateurs will use it is
another.

As I see it, you might invent a telescope whose primary, probably a mirror, can
do it, but its utility might be questionable, depending on the method chosen to
measure the wavefront distortion, but an add-on to an existing system doesn't
seem to be practical. Then there's the question of the economics of it all.

This has been the trend for decades now. The professionals come up with some
idea for their requirements. Some amateurs with enough resources to try it for
themselves find a more economical way to do it, but there is either not enough
interests in the possibilities or enough amateurs with the right resources to
copy the attempt. If both of these problems are overcome, then it starts making
significant inroads into the amateur community. Autoguiding, CCD imaging, even
webcams which can be seen as fast data takes ala scintillation imagers (but used
for different purposes and goals) were done via this route. Not everything has
flowed in this direction of course, because the requirements of the
professionals don't necessarily overlap with those of the amateur, but some
have.
--
Sincerely,
--- Dave
----------------------------------------------------------------------
It don't mean a thing
unless it has that certain "je ne sais quoi"
Duke Ellington
----------------------------------------------------------------------