Fourier Transform Spectroscopy - Converting Spectra From Time Domain To Frequency Domain

Converting Spectra From Time Domain To Frequency Domain

S(t) = \int_{-\infty}^\infty I(\nu) e^{- i\nu 2\pi t}\,d\nu

The sum is performed over all contributing frequencies to give a signal S(t) in the time domain.

I(\nu) = \int_{-\infty}^\infty S(t) e^{i\nu 2\pi t}dt

gives non-zero value when S(t) contains a component that matches the oscillating function.
Remember that

Read more about this topic:  Fourier Transform Spectroscopy

Famous quotes containing the words converting, time, domain and/or frequency:

    “A way of certifying experience, taking photographs is also a way of refusing it—by limiting experience to a search for the photogenic, by converting experience into an image, a souvenir. Travel becomes a strategy for accumulating photographs.”
    —Susan Sontag (b. 1933)

    “As yesterday and the historical ages are past, as the work of today is present, so some flitting perspectives and demi-experiences of the life that is in nature are in time veritably future, or rather outside of time, perennial, young, divine, in the wind and rain which never die.”
    —Henry David Thoreau (1817–1862)

    “While you are divided from us by geographical lines, which are imaginary, and by a language which is not the same, you have not come to an alien people or land. In the realm of the heart, in the domain of the mind, there are no geographical lines dividing the nations.”
    —Anna Howard Shaw (1847–1919)

    “One is apt to be discouraged by the frequency with which Mr. Hardy has persuaded himself that a macabre subject is a poem in itself; that, if there be enough of death and the tomb in one’s theme, it needs no translation into art, the bold statement of it being sufficient.”
    —Rebecca West (1892–1983)