Re: [ATM] Large Amateur Telescope

["Vladimir Galogaza" <vladimir.galogaza@zg.htnet.hr>]

>I am told that before Lauterbur's 1973 Nature paper, there were reputable
>scientists who said you can't use radio waves to create useful images.

And what is radio astronomy doing?



>Of course MR imaging is really in the magnetic gradient, but it "uses radio
>waves to create images."

Magnetic Resonance of particular atomic nuclei is obtained (for fixed
exciting frequency) only if the magnetic field
has right value. In MRI only some pixels (with known location) have right
magnetic field
intensity and intensity of the response of relaxing nuclei is attached to
those pixels.
Therefore radio frequency wavelength has nothing to do in spatial
determination of image pixels
position which is imaging part of the proces.
Radio waves are present only for nuclear spin fliping and their role in
imaging has nothing to do with phisical fact that
it is not possible to locate (image) objects smaller than used wavelength,
formulation you have used
in this thread.

Vladimir.






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