X-ray generating apparatus includes X-ray generating unit having first and second bottom surfaces and side surface; driving circuit; accommodation housing accommodating the X-ray generating unit and the driving circuit; and insulating component arranged in the accommodation housing and having first insulating member arranged between the driving circuit and the accommodation housing and second insulating member arranged between the X-ray generating unit and the accommodation housing. First space is defined between the first insulating member and the accommodation housing, second space is defined between the second insulating member and the accommodation housing, third space is defined between the side surface and the second insulating member, fourth space is defined by the second bottom surface and internal surface of the first insulating member. The second space communicates with the third space, the first space communicates with the fourth space.

Various systems are provided for a cathode of an X-ray imaging system. In one example, a shield assembly for a cathode comprises a first shield part and a second shield part, the first shield part and the second shield part spaced apart such that the first shield part and the second shield part are not in direct physical contact.

The present invention provides an X-ray source comprising: an anode electrode on which a target is formed; a tubular-shaped first housing which is made of an insulating material and at one end of which the anode electrode is provided; a tubular-shaped second housing which is made of a conductive material and one end of which is connected to the first housing; and a cathode electrode which is provided at the other end of the second housing and has an emitter formed opposite to the target.