# US 2014/0192957 A1 · X-ray generation apparatus and x-ray radiographic apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0192957 A1 - Document ID: US20140192957A1 - Status: Published application - Kind: A1 - Application number: 14/241,817 - Filed: 2012-08-29 - Published: 2014-07-10 - Earliest claimed: 2011-08-31 - Assignees: Canon Kabushiki Kaisha - Inventors: Miki Tamura; Tamayo Hiroki; Shigeki Matsutani; Takao Ogura; Kazuyuki Ueda; Yoshihiro Yanagisawa; Ichiro Nomura - Web page: https://patentgrep.com/patent/US20140192957A1 ## CPC - H01J 35/116: {Transmissive anodes (acting as a window H01J35/186)} - G01N 23/04: and forming images of the material - H01J 35/16: Vessels; Containers; Shields associated therewith - H05G 1/70: Circuit arrangements for X-ray tubes with more than one anode; Circuit arrangements for apparatus comprising more than one X ray tube {or more than one cathode (H05G1/58 takes precedence)} - H01J 35/186: {used as targets or X-ray converters} - H01J 2235/168: against charged particles - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H05G: X-RAY TECHNIQUE (investigating or analysing materials by the use of X-rays G01N23/00; apparatus for X-ray photography G03B42/02; X-ray tubes H01J35/00; TV systems having X-ray input H04N5/321) ## Abstract In an X-ray generation apparatus of transmission type including an electron emission source, and a target generating an X-ray with collision of electrons emitted from the electron emission source against the target, the X-ray generation apparatus further includes a secondary X-ray generation portion generating an X-ray with collision of electrons reflected by the target against the secondary X-ray generation portion, and the secondary X-ray generation portion and the target are arranged such that the X-ray generated with the direct collision of the electrons against the target and the X-ray generated with the collision of the electrons reflected by the target against the secondary X-ray generation portion are both radiated to an outside. X-ray generation efficiency is increased by effectively utilizing the electrons reflected by the target. ## Claims ### Claim 1 A X-ray generation apparatus of transmission type comprising: an electron emission source; and a target generating an X-ray with collision of electrons emitted from the electron emission source against the target, wherein the X-ray generation apparatus further comprises a secondary X-ray generation portion generating an X-ray with collision of electrons reflected by the target against the secondary X-ray generation portion, and the secondary X-ray generation portion and the target are arranged such that the X-ray generated with the direct collision of the electrons against the target and the X-ray generated with the collision of the electrons reflected by the target against the secondary X-ray generation portion are both radiated to an outside. ### Claim 2 (depends on 1) The X-ray generation apparatus according to claim 1, further comprising an electron passage surrounded by and formed in an electron passage forming member, and positioned on one side of the target closer to the electron emission source, wherein the electrons emitted from the electron emission source collide against the target after passing through the electron passage, and the secondary X-ray generation portion is disposed in the electron passage and protrudes to cover above a surface of the target against which the electrons collide. ### Claim 3 (depends on 1) The X-ray generation apparatus according to claim 1, wherein the target reflects 20% to 60% of the colliding electrons. ### Claim 4 (depends on 2) The X-ray generation apparatus according to claim 2, wherein an angle θ formed by the secondary X-ray generation portion and the target satisfies a following relationship of: 10°<θ<85°. ### Claim 5 (depends on 2) The X-ray generation apparatus according to claim 2, wherein a cross-sectional area of the electron passage at least at an end thereof on a side closer to the target is increased in comparison with a cross-sectional area of the electron passage on a side farther away from the target, and at least a part of an inner wall surface of a region of the electron passage where the cross-sectional area thereof is increased serves as the secondary X-ray generation portion. ### Claim 6 (depends on 5) The X-ray generation apparatus according to claim 5, wherein an opening size (2R) of the electron passage at the end thereof on the side farther away from the target and a distance (Z) from an end of the secondary X-ray generation portion on the side closer to the target to an end of the secondary X-ray generation portion on the side farther away from the target satisfy a following relationship of: 2R≦Z≦20R. ### Claim 7 (depends on 5) The X-ray generation apparatus according to claim 5, wherein the cross-sectional area of the electron passage is increased toward at least the end thereof on the side closer to the target with a step-like change. ### Claim 8 (depends on 5) The X-ray generation apparatus according to claim 5, wherein the cross-sectional area of the electron passage is continuously increased toward at least the end thereof on the side closer to the target. ### Claim 9 (depends on 8) The X-ray generation apparatus according to claim 8, wherein the cross-sectional area of the electron passage is linearly increased toward at least the end thereof on the side closer to the target. ### Claim 10 (depends on 8) The X-ray generation apparatus according to claim 8, wherein the cross-sectional area of the electron passage is increased toward at least the end thereof on the side closer to the target such that a cross-section of the electron passage has an upwardly convex circular-arc shape. ### Claim 11 (depends on 8) The X-ray generation apparatus according to claim 8, wherein the cross-sectional area of the electron passage is increased toward at least the end thereof on the side closer to the target such that a cross-section of the electron passage has a downwardly convex circular-arc shape. ### Claim 12 (depends on 1) The X-ray generation apparatus according to claim 1, wherein at least a part of the X-ray generated upon the collision of the reflection electrons against the secondary X-ray generation portion transmits through a region of the target against which the electrons collide. ### Claim 13 (depends on 12) The X-ray generation apparatus according to claim 12, wherein the target is made of one of tungsten, tantalum and molybdenum. ### Claim 14 The X-ray generation apparatus according to claim wherein the secondary X-ray generation portion is made of one of tungsten, tantalum and molybdenum. ### Claim 15 (depends on 12) The X-ray generation apparatus according to claim 12, wherein the target is disposed on a surface of a support base, which surface is positioned to face the electron emission source. ### Claim 16 (depends on 15) The X-ray generation apparatus according to claim 15, wherein the support base is made of one of diamond, silicon nitride, and aluminum nitride. ### Claim 17 (depends on 2) The X-ray generation apparatus according to claim 2, wherein the electron emission source is disposed inside a vacuum vessel, and the electron passage forming member is disposed in an opening of the vacuum vessel. ### Claim 18 (depends on 17) The X-ray generation apparatus according to claim 17, wherein the vacuum vessel is disposed in an envelope, and an insulating medium is filled in an empty space between the vacuum vessel and the envelope. ### Claim 19 (depends on 18) The X-ray generation apparatus according to claim 18, wherein a voltage control unit configured to output a voltage signal for controlling the generation of the X-ray is disposed inside the envelope. ### Claim 20 An X-ray radiographic apparatus comprising: an X-ray generation apparatus of transmission type including; an electron emission source, and a target generating an X-ray with collision of electrons emitted from the electron emission source against the target, the X-ray generation apparatus further including a secondary X-ray generation portion generating an X-ray with collision of electrons reflected by the target against the secondary X-ray generation portion, the secondary X-ray generation portion and the target being arranged such that the X-ray generated with the direct collision of the electrons against the target and the X-ray generated with the collision of the electrons reflected by the target against the secondary X-ray generation portion are both radiated to an outside; an X-ray detector configured to detect an X-ray having been radiated from the transmission-type X-ray generation apparatus and having transmitted through a subject; and a control unit configured to control the X-ray generation apparatus and the X-ray detector.