1. A method for generating spectral images of an object in an optical system comprising the steps of: illuminating the object with a modified illumination profile of the optical system; producing a reflected, transmitted or fluorescence light image of the illuminated object by introducing a second optical system; re-imaging the light image on at least one detector after modifying the light's optical state to achieve both high-spectral and high-temporal resolution imaging; and scanning the object by a scanning means.