Device and method for measuring alignment errors of a directed beam source

A device for measuring alignment errors of a directed beam source the device comprising:

• a mounting for the beam source,
• a first spatially resolving radiation sensor,
• a beam splitter configured to split a beam generated by the beam source into a first component beam and a second component beam,
• a focusing optics unit arranged in a beam path of the first component beam and having a focal plane in which the first radiation sensor is arranged,
• a second spatially resolving radiation sensor arranged in a beam path of the second component beam,
• a drive configured to bring about relative movement about an axis of rotation between firstly the mounting and secondly the other parts of the device listed above,
• a computing means configured to calculate a tilt and a lateral offset of the beam generated by the beam source the calculation using first locations on the first radiation sensor that the first component beam sweeps over during a rotation of the beam source relative to the other parts of the device listed above and using second locations on the second radiation sensor that the second component beam sweeps over during the rotation of the beam source relative to the other parts of the device listed above.