On a sunny day (Mon, 21 Mar 2005 08:00:18 -0500) it happened DustyMars
wrote in :

In article ,
says...
I consider designing a low-cost AO system for a small telescope. It
seems we have all necessary resources: we produce deformable mirrors and
wavefront sensors, we also produce closed-loop AO systems with up to 59
channels, so integration wouldn't be too complicated as all structural parts
are available.

On the other hand we have little experience with astronomy and therefore any
advice would help.

The preliminary tech requirements:

1. To be mounted in 1.25 inch ocular socket (2" socket??). To be used with
telescopes with diameter in the range 25cm to 1m.

2. Aberration free afocal mirror system, transparent in the visible and
near IR and fully operational even with AO switched off. To achieve this,
we'll use a system with a field of a couple of mm (in the primary focus)
for a foacl ratio of 1/10. The field and F# are compromized to reduce the
complexity of the optics, but the field will be limited anyway by the
anisoplanatism of the AO and the F# must be small for a HR imaging

3. To have al least 19 degrees of freedom (depending on the seeing can be
good to correct up to ~13 Zernike terms to about 10% of the uncorrected
value). 37 degrees of freedom is also possible but I'm not sure a small
scope really will collect enough light to correct that many terms in real
time.

4. To operate on a natural star with magnitude of at least 4 (with a 25cm
telescope), using 50% of light for running the AO and 50% for registration.

5. To be easy in setting up and running. To use single +12V power supply
and three cables connecting the system with the deformable mirror
controller and the dedicated control laptop PC.

6. The total weight of the optical correction unit mounted to the telescope
not to exceed 1kg. Mirror controller incl power supply - also 1 kg, add some
extra for cables and laptop.


The system is supposed to provide a diffraction-limited imaging in a rather
bad seeing conditions. It will allow stable imaging of bright objects such
as stars, double stars and planets. Another advantage of using such a
system is that it will correct the aberrations of the telescope, improving
the quality of optics, for instance making the period of mirror cooling also
available for observations. In fact, correction of the static aberrations
can be done on a bright star once, and then the system can be used in
static correction mode.

The project is technically feasible (although quite expensive in its
development stage), but I still have my doubts regarding its usefulness:

An interesting article on the practical application of Adaptive optics
can be found he
http://www.journals.uchicago.edu/AJ/...90240/brief/99
0240.abstract.html
I have been wondering if somehow fluid lenses could be used for adaptive
optics in a telescope.
Then you could use electical voltages to change lens properties locally.
http://www.heise.de/newsticker/resul...einze%20Linsen
It is a German article, in short it describes a lens formed by a layer of oil
on a layer of some other fluid, with an electical field applied.
These lenses are extremely small, a French company has already made a zoom
objective for a cellphone camera with this technology.
http://www.varioptic.com/en/
It uses less power then a mechanical construction.
I wonder if a big one could be made....