Patent ID: 8351575

Claim:
A radiation source for X-ray generation for examining an object of interest, the source comprising: a first carbon nanotube for emitting first electrons in response to a first acceleration voltage applied to the first carbon nanotube and a second carbon nanotube for emitting second electrons in response to a second acceleration voltage applied to the second carbon nanotube, the second acceleration voltage being adjusted independently from the first acceleration voltage; a target; and a focusing unit for focusing the first and the second electrons onto the target to generate first X-ray photons of a first energy having a first trajectory and second X-ray photons of a second energy having a second trajectory, wherein a difference between the first and second acceleration voltages enables a difference of energy between the first X-ray photons and the second X-ray photons, and wherein 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.