公开(公告)号：CH614313A5

公开(公告)日：1979-11-15

申请号：CH564475

申请日：1975-05-02

Applicant: GEN ELECTRIC

Inventor： HEITING ROBERT FRANCIS ,  RATE EDWARD TAYLOR

IPC: H01J35/14 ,  H05G1/52

Abstract: An electron tube such as an x-ray tube has an anode target spaced from an electron beam emitting structure which include a cathode, focusing electrode and a control electrode. The control electrode surface nearest the anode is contoured to conform with selected equipotential values in the electrostatic field between the cathode and anode which equipotential is a predetermined percentage of the total cathode to anode voltage. When the control electrode is operated at a corresponding positive potential, the electrons follow certain trajectories and focus on the anode. Means are provided for varying the control voltage through a range from beam cut-off voltage to various positive voltages that permit control of the focal spot size regardless of the selected beam current and selected anode voltage.

公开(公告)号：CH601915A5

公开(公告)日：1978-07-14

申请号：CH749175

申请日：1975-06-10

Applicant: GEN ELECTRIC

Inventor： RATE EDWARD TAYLOR ,  HEITING ROBERT FRANCIS

IPC: H01J35/04 ,  H01J35/06 ,  H01J35/26 ,  H01J35/14

Abstract: An X-ray generator has a Pierce type electron gun comprising an electron emissive cathode, field shaping electrodes connected thereto, a first accelerating anode spaced from the cathode and an X-ray target anode spaced from the accelerating anode for being impinged upon by a focused electron beam. Control grid means are disposed between the cathode and the first anode. The grid means are constructed such that with use of proper grid potentials, the electron beam may be selectively biased to cutoff or electrons can be withdrawn from selected areas of the cathode or from the entire cathode to produce focal spots of different sizes and various electron current magnitudes on the target anode.

公开(公告)号：FR2275021A1

公开(公告)日：1976-01-09

申请号：FR7518831

申请日：1975-06-17

Applicant: GEN ELECTRIC

Inventor： RATE EDWARD TAYLOR ,  HEITING ROBERT FRANCIS

IPC: H01J35/04 ,  H01J35/06 ,  H01J35/26 ,  H01J35/00

Abstract: An X-ray generator has a Pierce type electron gun comprising an electron emissive cathode, field shaping electrodes connected thereto, a first accelerating anode spaced from the cathode and an X-ray target anode spaced from the accelerating anode for being impinged upon by a focused electron beam. Control grid means are disposed between the cathode and the first anode. The grid means are constructed such that with use of proper grid potentials, the electron beam may be selectively biased to cutoff or electrons can be withdrawn from selected areas of the cathode or from the entire cathode to produce focal spots of different sizes and various electron current magnitudes on the target anode.

公开(公告)号：DE2525159A1

公开(公告)日：1976-01-02

申请号：DE2525159

申请日：1975-06-06

Applicant: GEN ELECTRIC

Inventor： RATE EDWARD TAYLOR ,  HEITING ROBERT FRANCIS

IPC: H01J35/04 ,  H01J35/06 ,  H01J35/26

Abstract: An X-ray generator has a Pierce type electron gun comprising an electron emissive cathode, field shaping electrodes connected thereto, a first accelerating anode spaced from the cathode and an X-ray target anode spaced from the accelerating anode for being impinged upon by a focused electron beam. Control grid means are disposed between the cathode and the first anode. The grid means are constructed such that with use of proper grid potentials, the electron beam may be selectively biased to cutoff or electrons can be withdrawn from selected areas of the cathode or from the entire cathode to produce focal spots of different sizes and various electron current magnitudes on the target anode.

公开(公告)号：DE2518688A1

公开(公告)日：1975-11-13

申请号：DE2518688

申请日：1975-04-26

Applicant: GEN ELECTRIC

Inventor： HEITING ROBERT FRANCIS ,  RATE EDWARD TAYLOR

IPC: H01J35/14 ,  H05G1/52 ,  H01J3/08 ,  H01J35/04

Abstract: An electron tube such as an x-ray tube has an anode target spaced from an electron beam emitting structure which include a cathode, focusing electrode and a control electrode. The control electrode surface nearest the anode is contoured to conform with selected equipotential values in the electrostatic field between the cathode and anode which equipotential is a predetermined percentage of the total cathode to anode voltage. When the control electrode is operated at a corresponding positive potential, the electrons follow certain trajectories and focus on the anode. Means are provided for varying the control voltage through a range from beam cut-off voltage to various positive voltages that permit control of the focal spot size regardless of the selected beam current and selected anode voltage.