Fourier transform of a phase function

Chen
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Hi,

I'm solving an exercise in optics (Fraunhofer diffraction) and reached a mathematical difficulty - I need to find the Fourier transform of a phase function, of the form exp[-i f(x)]. I can't seem to be able to do this. I have an idea that the result should be a series of delta functions, corresponding with the zeroes of x-f(x) (to some factors). Is this true? If not, how can I solve this problem?

If it's relevant to the answer, the function in question f(x) is a periodic triangular wave, with arbitary height/width ratio.

Thanks,
Chen
 
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Disregard, thanks.

Chen
 
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