Radiation generating tube and radiation generating apparatus using the same

An x-ray radiation generating tube, comprising:

• a cathode connected to an electron emitting member including an electron emitting portion;
• an anode which includes a target that generates a ray when irradiated with electrons emitted from the electron emitting portion;
• and
• an insulating tube disposed between the cathode and the anode to surround the electron emitting member,
• wherein:
• the insulating tube includes an electrical potential defining disposed at an intermediate portion of the insulating tube between the cathode and the anode in a longitudinal axis direction, the electrical potential defining member being electrically connected to an electrical potential defining unit, and the potential of the electrical potential defining member being controlled to be higher than the potential of the cathode and lower than the potential of the anode;
• a boundary of the electrical potential defining member and the insulating tube does not face a portion of the anode exposed to the inside of the radiation generating tube;
• the electrical potential defining member does not include a corner which faces the portion of the anode exposed to the inside of the radiation generating tube;
• and
• an end of the electrical potential defining member on the inner side of the radiation generating tube is covered with an insulating member.

An x-ray radiation generating tube, comprising:

• a cathode connected to an electron emitting member including an electron emitting portion;
• an anode which includes a target that generates a ray when irradiated with electrons emitted from the electron emitting portion;
• and
• an insulating tube disposed between the cathode and the anode to surround the electron emitting member,
• wherein:
• the insulating tube includes an electrical potential defining disposed at an intermediate portion of the insulating tube between the cathode and the anode in a longitudinal axis direction, the electrical potential defining member being electrically connected to an electrical potential defining unit, and the potential of the electrical potential defining member being controlled to be higher than the potential of the cathode and lower than the potential of the anode;
• a boundary of the electrical potential defining member and the insulating tube does not face a portion of the anode exposed to the inside of the radiation generating tube;
• the electrical potential defining member does not include a corner which faces the portion of the anode exposed to the inside of the radiation generating tube;
• the electrical potential defining member is provided on an outer surface of the insulating tube;
• and
• another electrical potential defining member which is capacitively coupled to the electrical potential defining member is fixed to an inner surface of the insulating tube so as to face the electrical potential defining member via the insulating tube.