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A comment on FFTs and Optical Lenses. Parent comment

Re:FFTs and Optical Lenses by skierscott on Tuesday May 27, 2014 @10:39PM (#7808109)
You are correct; the FFT or DFT is not the same thing as the continuous-time Fourier transform (CFT).

This technical report[1] examining the relation between the DFT and CFT shows in eq. 20 that the DFT is just the CFT evaluated at w=k2pi/(N*T). As N becomes large (number of pixels is large), this approaches the CFT.

I left this detail out; I wanted to put this in terms the reader knew.

[1]:http://bsp.pdx.edu/Reports/BSP-TR0201.pdf

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Re:FFTs and Optical Lenses by panic on Tuesday May 27, 2014 @11:42PM (#7808293)
If you just left out one "F" from "FFT" it would be more precise and less confusing. Is there any reason to bring the Fast Fourier Transform algorithm up at all?
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Re:FFTs and Optical Lenses by science404 on Wednesday May 28, 2014 @08:00AM (#7809460)
Not to the mention the fact that the FFT is an algorithm to compute the DFT. So calling the Fourier transform an FFT is even more of a misnomer.
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