light incidence into the exit pupil 14 of objective 4 when the wavelength dependent heights h are known the chromatic magnification aberration resulting from the correction unit 5 can be designed in such a way that the optical rays s 1 s 2 with the different wavelengths of the ray bundle 15 supplied to the correction unit 5 pass through the exit pupil 14 at the calculated heights h furthermore the axial distance of the ray bundle 15 from the optical axis of the correction optics 3 can be changed in the device of fig1 as is indicated by the double arrow p 2 the penetration depth can be varied via this change of distance the change of distance can occur especially via an actuator not shown when the penetration depth is set in this manner to a value other than the 93 nm as assumed here a reduction of the different wavelength dependent penetration depths is still achieved by means of the correction unit 5 it may occur however that the penetration depths are no longer precisely the same however the difference of the penetration depths is considerably lower in comparison with a case without the corrective unit 5 in accordance with the invention the following table 1 shows the radii and distances of the individual areas of the lenses l 1 to l 5 and the respective refractive index of the used lens materials another possible correction unit 5 is shown in fig3 in this case the correction unit comprises an inclined planar plate 17 and compensates the chromatic differences of the penetration d for 425 nm and 575 nm further possible correction units are shown.