Measurement of the dynamic structure function of fluorescently labeled complex fluids by Fourier imaging correlation spectroscopy

Wave-number-resolved time-correlation functions of density fluctuations are determined from purely incoherent fluorescence signals using a new method, Fourier imaging correlation spectroscopy (FICS). We demonstrate the applic ation of FICS to chemical and biological samples with ultrahigh signal sens itivity and time resolution superior to direct imaging methods. We outline the theory that establishes the connection between FICS observables and sta tistical mechanical quantities describing liquid state dynamics.