| 摘要 |
An integral cathode (200) for use with x-ray devices (102). The integral cathode (200) includes an emitter (202) made of a refractory metal such as tungsten, preferably doped with rhenium to afford malleability during constructions and assembly. The integral ctahode (200) also includes a support cartridge (204), preferably composed of an electrically non-conductive material such as ceramic, in which the emitter (202) is received. The support cartridge (204) electrically isolates the cathode (200) from the other components and structures of the x-ray device (102). Additionally, the support cartridge (204) serves to impose, and maintain, a parbolic curve in the emitter (202). The parabolic form of the emitter (202) naturally shapes an electron beam by causing electrons discharged from the emitter to converge at a focal spot (106). In this way, both the emission and focusing functions of the cathode (200) are integrated and performed by a single part.
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