[Chaos-l] flat lenses

[Alexey Toptygin]

On Mon, 27 Aug 2012, Robert Nielsen wrote:

> Alexey,
>
> OK ... having a degree in physics (which I haven't used in a long time) 
> ... it seems to me that you could focus more than one wavelength at the 
> same time, by putting different sets of nano antennas, sorta like your 
> cell phone has a fractal antenna that receives multiple frequencies at 
> the same time.  But they would be discrete, specific wavelengths ... so 
> you still wouldn't get the same view as with a normal refractor.  But 
> perhaps you could pick up multiple wavelengths, like a UHC filter ...

IIUC that would either mean you'd be splitting up the lens area into parts 
that focus each wavelength (and thus the effective apperature at each 
wavelength would decrease) and/or you'd get multiple focal lengths at each 
wavelength (one from each 'focusing system' targeted at a particular 
wavelength) so in the focal plane you'd get defocused 'images' at each 
wavelength from the 'focusing systems' designed for the other wavelengths 
of interest.

 			Alexey