X-RAY TUBE

摘要

In an X-ray tube having an X-ray shielding member (110) allowing an electron ray to pass through an electron passing hole toward a target (108), separately from the cathode-side opening of the electron pass¬ ing hole, a gas exhaust path (112) allowing communication between the inside and outside of the electron passing hole is provided so that gas molecules generated in the electron passing hole can be easily diffused out of the electron passing hole. The degradation of the cath¬ ode caused by accelerated collisions with the cathode, of cations gen¬ erated by collisions of electrons with gas molecules generated in the electron passing hole by a desorption phenomenon due to electron ray irradiation to the target, is reduced.