Exposure optics and device for producing a three-dimensional object

An exposure optics as an equipping and/or retrofitting optics for a device for producing a three-dimensional object by selectively solidifying building material, layer by layer, at positions that correspond to a cross-section of the object to be produced in the respective layer by electromagnetic radiation, wherein the device comprises a radiation source capable of emitting the electromagnetic radiation in a plurality of beams each of which is suited to cause solidification of the building material at positions of a layer of the building material applied in a working surface of the device, the positions corresponding to the cross-section of the object to be produced, when impinging on the positions, the exposure optics comprising:

• at least a first beam source facing lens system having a first focal length f1 and a second working surface facing lens system having a second focal length f2, the lens systems being arranged in the beam paths of the radiation emitted by the radiation source, the beam paths being in a straight linear array between the lens systems,
• the focal plane of the first lens system and the focal plane of the second lens system coinciding in a plane between the two lens systems;
• and
• the focal length f1 of the first lens system is equal to or greater than the focal length f2 of the second lens system, and the beams from the working surface sided lens system are focused to impinge substantially perpendicular on the working surface.