Observation, wavelength and resolution

[the4thamigo_uk]

Why are short wavelengths (of e.m. radiation say) required for observing the location of a small particle? Classically, I could imagine sending a wave train of light (or a photon) of different frequencies onto an atom in free space. Providing the electrons in the energy levels of the atom can absorb and re-emit those frequencies, then I should be able to locate the particle using a detector with the same precision whatever the wavelength of the incident photon?

So what is the underlying reason why the wavelength of the incident light must be of the same scale as the object?

[Rajini]

Do you know the relationship between the wavelength (of beam/ray that you use to probe the sample/particle etc) and resolution ? Resolution is limited by wavelength.
If not please find some information of the following:
1. Abbe criterion (it gives you some rough comparison of resolution in light, electron microscopes)
2. Scherzer resolution (may be you find some information)
But errors are unavoidable, so you often cannot go much into detail up to pm range.
Errors are Aberration,

[GRDixon]

[QUOTE=the4thamigo_uk;2822448what is the underlying reason why the wavelength of the incident light must be of the same scale as the object?[/QUOTE]

I can recommend "The Feynman Lectures on Physics," Volume 2, Section 29-5 ("The electron microscope).

[Creator]

Imaging detail is a diffraction limited process....
Angular resolution is based on a fairly simple formula called the "Rayleigh criteria".
See... http://en.wikipedia.org/wiki/Angular_resolution

For a more pictorial explanation see : http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/raylei.html

Creator