An apparatus for the detection of spectral information along a geometrical line with a dispersive element, which is suspended from an axis of rotation, for the spectral dispersion of electromagnetic radiation from a range on the geometrical line into spectral constituents, a line detector for the detection of the spectral constituents of the radiation emanating from the range on the geometrical line and a dispersive-element deflector, the deflector being designed to deflect the dispersive element on the axis of rotation, so that depending on an angle of deflection a radiation from another range of the geometrical line is incident on the line detector.