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Hologram Telescope



 
 
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  #11  
Old April 26th 05, 01:41 AM
thanatos
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there are severl ways to do this

1) a hot plasma is transparent, and magnetically confinable/ shapeable -
google Fresnel Oscillations
2) water is a polar molecule - use a static field to shape a water lens
3) if you look at the eigenmodes of oscillation of a 'drum' you may be able
to produce a fresnel zone plate in some kind of optical medium via magneto
acoustics
4) with the advent of new electro optice materials, it may be possible to
induce optical holographic effects in a material

couple this with high speed detectors and image processing and it may be
possible to have super resolved holographic imaging


soon if not now


"phoenix" wrote in message
oups.com...

Theoretically. Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front. I like the idea of a very lightweight
0 wave error 6" refractor that I can carry at my back when
hiking and just putting it on the equally lightweight image
stabilizer mount when the sky has a great view.

In 4000 A.D. Can the above occur.. theoretically??

phoenix



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  #12  
Old April 26th 05, 05:32 AM
Coppy Littlehouse
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phoenix wrote:

Strong mass can bend light. Maybe putting heavy neutron star matter
at the periphery of the tube?? But then it's no longer lightweight
unless 4000 A.D. technology has developed antigravity so you can
take it along with you as well as higgs field suppressor to prevent
the heavy neutron star mass from being formed while being carried.


If you have anti-gravity at your disposal, you won't need neutron star
matter. The anti-gravity emitter can bend (unbend?) light all by
itself. That's all you need, an anti-gravity lens. It would work like
the Einstein Cross gravitational lens, only smaller and the other way
around.

http://www.astr.ua.edu/keel/agn/qso2237.html

  #13  
Old April 26th 05, 08:58 AM
Martin Brown
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phoenix wrote:
Theoretically. Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front. I like the idea of a very lightweight
0 wave error 6" refractor that I can carry at my back when
hiking and just putting it on the equally lightweight image
stabilizer mount when the sky has a great view.

In 4000 A.D. Can the above occur.. theoretically??


Theoretically anything that is not prevented by the laws of physics is
possible. However, many practical limitations do get in the way. Most
notably that a hologram uses diffraction and so will suffer from
horrific chromatic abberations unless it is used for monochromatic
light. Fresnel zone plates can already be used to form crude images by
diffraction. If you can live with the image quality. e.g



They have their own following in the pinhole camera community.

You could argue with some justification that modern aperture synthesis
radio telescopes are in effect holographic instruments since they
combine the phase compensated coherent signals sampled at various
locations (and times) to compute what would have been seen by a real
filled aperture.

The phase compensation issues are so difficult that I doubt if anyone
will ever make a portable optical aperture synthesis scope...

Regards,
Martin Brown
  #14  
Old April 26th 05, 04:50 PM
[email protected]
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"Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front."

Not quite, but about 15 years ago I read an article in Advanced Optics
that whowed if you took a 1 wave reflector, a laser, and a holographic
plate, that you could print the wavefront error on that plate. Then
later after the plate was developed, you could use the plate to convert
the scope from a 1 wave monster into a 1/3 wave--almost
tollerable--scope. However, the colimation tollerances with respectof
plate to optical axis were "really stiff".

Mitch

  #15  
Old April 26th 05, 06:25 PM
Dan Mckenna
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A while ago I saw a product called "digilens"
that was 3 ? diffractive lenses in one lens holder.
You could switch between them with an address line.
The optical properties of this optic were programmed at the factory.
The one I saw (photo) had 2 positive and one negitive lenses of
different focal lengths IIRC

Dan


wrote:
"Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front."

Not quite, but about 15 years ago I read an article in Advanced Optics
that whowed if you took a 1 wave reflector, a laser, and a holographic
plate, that you could print the wavefront error on that plate. Then
later after the plate was developed, you could use the plate to convert
the scope from a 1 wave monster into a 1/3 wave--almost
tollerable--scope. However, the colimation tollerances with respectof
plate to optical axis were "really stiff".

Mitch


  #16  
Old April 27th 05, 04:44 AM
Drew
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On 25 Apr 2005 03:14:12 -0700, "phoenix" wrote:


Theoretically. Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front. I like the idea of a very lightweight
0 wave error 6" refractor that I can carry at my back when
hiking and just putting it on the equally lightweight image
stabilizer mount when the sky has a great view.

In 4000 A.D. Can the above occur.. theoretically??


I can't see holographic equipment being very portable at first. Even
when it is, I'm sure it will be easier to simply GO within a few dozen
light years of the Great Orion Nebula and get a real view or take up a
nice spot on Ganymede on the sub-Jovian side at night and watch the
GRS spin or use 10x50 binoculars to watch the latest Pele eruption on
Io. Guess we'll still need telescopes to see galaxies though. :-)

Later generation light intensifiers and liquid mirrors are likelier to
make amateur astronomy more enjoyable before the advent or portable or
amateur holography equipment.

-Drew

  #17  
Old April 27th 05, 02:19 PM
phoenix
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Drew wrote:
On 25 Apr 2005 03:14:12 -0700, "phoenix" wrote:


Theoretically. Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front. I like the idea of a very lightweight
0 wave error 6" refractor that I can carry at my back when
hiking and just putting it on the equally lightweight image
stabilizer mount when the sky has a great view.

In 4000 A.D. Can the above occur.. theoretically??


I can't see holographic equipment being very portable at first. Even
when it is, I'm sure it will be easier to simply GO within a few

dozen
light years of the Great Orion Nebula and get a real view or take up

a
nice spot on Ganymede on the sub-Jovian side at night and watch the
GRS spin or use 10x50 binoculars to watch the latest Pele eruption on
Io. Guess we'll still need telescopes to see galaxies though. :-)

Later generation light intensifiers and liquid mirrors are likelier

to
make amateur astronomy more enjoyable before the advent or portable

or
amateur holography equipment.

-Drew


Maybe a 4" holographic lens is a bad idea. Perhaps it would
be far more useful to have much bigger aperture like 10"
refractor. As you know. Big aperture refractor costs like
crazy. Maybe they can invent something that can collect the
photons in a say 20 inches area and focus the beam to the
focal point that doesn't even use glass but other methods
such some kind of wave guide to guide all the waves into a
point at the focal plane. Got any idea how or what that can
do it roughly even on a theoretical basis first awaiting
technology advances thousands of years far into the future.
Well. It's not bad to start thinking of it now as we may be
able to build a rough device that can do it.

P

  #18  
Old May 2nd 05, 07:08 AM
Ten Dog Lawn
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William McHale wrote:

RichA wrote:
On 25 Apr 2005 03:14:12 -0700, "phoenix" wrote:



Theoretically. Is it possible to construct a telescope using
holographic lens such that you flick a switch and the lens
just formed at the front. I like the idea of a very lightweight
0 wave error 6" refractor that I can carry at my back when
hiking and just putting it on the equally lightweight image
stabilizer mount when the sky has a great view.

In 4000 A.D. Can the above occur.. theoretically??

phoenix


No. I don't care what they could do on the Enterprise holodeck, it
was all nonsense. But, maybe a ring of controllable and tiny black
holes around the periphery of the objective opening could be used to
"bend light" to achieve the results you're looking for. Kind of like
how an electron microscope uses magnets instead of lenses to
manipulate electrons.


You could also put a single slightly larger black hole in the center of the
objective opening. Of course this would not make refractor people happy since
you would now have an obstructed system.


not to mention instant vanishing of the observer! Oooooops.




 




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