Examination apparatus for the examination of an object of interest, the apparatus comprising: - a detector; - a radiation source for X-ray generation for examining an object of interest, the source comprising: at least a first carbon nanotube based emitter for emitting first electrons and at least a second carbon nanotube based emitter for emitting second electrons forming a group of carbon nanotubes based emitters; a target, the group of carbon nanotubes based emitters being located in a circular geometry around the target; a focusing unit (7, 9) for focusing the first and the second electrons onto the target to generate first X-ray photons having a first trajectory and second X-ray photons having a second trajectory and arranged such that the object of interest, being present between the target and the detector, is illuminated by both the first and the second X-ray photons and the detector converts the information of the transmitted X-ray photons into projection images; and characterised in that the target has a cone geometry and the focusing unit is adapted for being operated in such a way, that the first and the second trajectories overlap before reaching the object of interest so that at the position of the object of interest the trajectories of the first and second X-ray photons are not distinguishable from each other. - a detector; - a radiation source for X-ray generation for examining an object of interest, the source comprising: at least a first carbon nanotube based emitter for emitting first electrons and at least a second carbon nanotube based emitter for emitting second electrons forming a group of carbon nanotubes based emitters; a target, the group of carbon nanotubes based emitters being located in a circular geometry around the target; a focusing unit (7, 9) for focusing the first and the second electrons onto the target to generate first X-ray photons having a first trajectory and second X-ray photons having a second trajectory and arranged such that the object of interest, being present between the target and the detector, is illuminated by both the first and the second X-ray photons and the detector converts the information of the transmitted X-ray photons into projection images; and characterised in that the target has a cone geometry and the focusing unit is adapted for being operated in such a way, that the first and the second trajectories overlap before reaching the object of interest so that at the position of the object of interest the trajectories of the first and second X-ray photons are not distinguishable from each other. at least a first carbon nanotube based emitter for emitting first electrons and at least a second carbon nanotube based emitter for emitting second electrons forming a group of carbon nanotubes based emitters; a target, the group of carbon nanotubes based emitters being located in a circular geometry around the target; a focusing unit (7, 9) for focusing the first and the second electrons onto the target to generate first X-ray photons having a first trajectory and second X-ray photons having a second trajectory and arranged such that the object of interest, being present between the target and the detector, is illuminated by both the first and the second X-ray photons and the detector converts the information of the transmitted X-ray photons into projection images; and characterised in that the target has a cone geometry and the focusing unit is adapted for being operated in such a way, that the first and the second trajectories overlap before reaching the object of interest so that at the position of the object of interest the trajectories of the first and second X-ray photons are not distinguishable from each other.