An X-ray tube includes an emitter, and an electrode assembly. The emitter is configured to emit an electron beam toward a target. The electrode assembly includes at least one electrode having a bias voltage with respect to the emitter. At least one electrode of the electrode assembly is a segmented electrode including a plurality of segments. The plurality of segments includes a first member and a second member. The first member is configured to have a first bias voltage and the second member is configured to have a second bias voltage that is different from the first bias voltage.