The invention provides an optical analysis system for efficient compensation of spectroscopic broadband back-ground, such as spectroscopic fluorescence background or background signals that are due to the dark current of a detector. The optical analysis system effectively provides multivariate optical analysis of a spectroscopic signal. It provides wavelength selective detection of various spectral components that are indicative of a superposition of spectroscopic peaks or bands and their broadband background. Additionally, the optical analysis system is adapted to acquire spectral components that predominantly correspond to the broadband background of the spectroscopic peaks or bands. Wavelength selective selection of various spectral components is performed on the basis of reconfigurable multivariate optical elements or on the basis of a position displacement of a spatial optical transmission mask.