An apparatus for producing three-dimensional work pieces is provided. The apparatus comprises a carrier configured to receive multiple layers of raw material, and an irradiation unit configured to generate a radiation beam and to direct the radiation beam to predetermined sites of an uppermost layer of the raw material in order to solidify the raw material at the predetermined sites. The irradiation unit comprises a radiation source configured to generate the radiation beam, a first scanning unit configured to receive the radiation beam and to scan the radiation beam over a first irradiation area of the uppermost layer of the raw material, a second scanning unit configured to receive the radiation beam and to scan the radiation beam over a second irradiation area of the uppermost layer of the raw material, and a switching unit configured to direct the radiation beam generated by the radiation source to the first scanning unit or the second scanning unit. The apparatus further comprises a control unit configured to perform control of the switching unit to switch from a first switching state, in which the radiation beam is directed to the first scanning unit and not to the second scanning unit, to a second switching state, in which the radiation beam is directed to the second scanning unit and not to the first scanning unit.