Graphene serving as cathode of X-ray tube and X-ray tube thereof

Graphene serving as the cathode of an X-ray tube, and a high-efficiency graphene cathode field emission X-ray tube. The graphene cathode field emission X-ray tube is high in conversion efficiency and less in stray radiation, reduces radiation dosage acting upon human body when used in the fields of medical treatment, security inspection and the like; the graphene cathode field emission X-ray tube is easy to realize a micro-focus X-ray tube, strong in emissive power and high in voltage resistance, and can be applied to the fields of semiconductor detection, industrial flaw detection and the like; in addition, the graphene cathode field emission X-ray tube is good in controllability, free from cathode heating. The graphene cathode field emission X-ray tube also has the characteristics of good stability and long service life.