A spectroscopic system which determines a property of a biological structure in a volume of interest of a person includes a low cost objective lens for directing an excitation beam into a volume of interest and for collecting return radiation from the volume of interest. After detection of the return radiation and generation of spectroscopic signals, a correction unit performs a compensation for aberrations of the spectroscopic signals introduced by the low cost objective lens. Since the aberrations of the objective lens strongly depend on the lateral distance of the volume of interest from the optical axis of the objective lens, the correction unit uses a correction table providing an assignment between correction values and various lateral positions of the volume of interest.