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Mathematically, real space and Fourier space are equivalent (via the Fourier transform). The Fourier domain also has some useful properties, such as efficiency in representing large objects and multi-resolution capabilities. I propose the use of Fourier goggles to automatically perform a Fourier transform
on normal visual input. They could be used for... well, I don't know what.
(???) Optical Fourier transform lab experiment
Here's a student lab experiment on doing the Fourier transform optically. [td, May 05 2001]
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||Err... FFT then. Probably.
||Possibly surprisingly, this is baked. An ordinary lens does a Fourier transform. This is routinely used to do spatial filtering optically -- you transform into Fourier space, use an ordinary neutral density filter to block selected frequencies and transform back. See the link.
||At work we have an optical gadget set up to measure the resolution of the images we put on film.
||Of course, it wasn't really
specified whether the Fourier
transform was with spatial or
temporal. (Spatial is probably a
better approximation; a temporal
Fourier transform would just be a
spectrogram of some sort, I guess.)
||Yes, we learned about optical transforms in image processing class. (You just focus a lens in a certain way, and the 2D transform of the intensity of the image appears.) But goggles! That is genius! I want to try it. Would it give us any information we can't glean with our plain 'ol eyes?
||If I remember right, holography works on somewhat related principles, but the interference patterns for different wavelengths of light do not coincide in any useful way.