X-ray generator, X-ray inspector and X-ray generation method

• US 6,456,690 B2
• Filed: 12/20/2000
• Issued: 09/24/2002
• Est. Priority Date: 06/08/2000
• Status: Expired due to Fees

• Current Assignee: Medixtec Japan Corporation
• Original Assignee: Medixtec Japan Corporation
• Inventors: Yamada, Koichi, Tanigaki, Takeshige
• Primary Examiner(s): Kim, Robert H.
• Assistant Examiner(s): WANG, GEORGE Y
• Application Number:
  US09/739,834
• Publication Number:
  US 20010050972A1
• Time in Patent Office: 643 Days
• Field of Search: 378/119, 378/127, 378/137, 378/138
• US Class Current: 378/119
• CPC Class Codes: H01J 35/116 Transmissive anodes acting as a window H01J35/186
• CPC Class Codes: H01J 35/147 Spot size control

Abstract

An X-ray generator, an X-ray inspector and an X-ray generation method capable of automatically focusing an energy beam, such as an electron beam for generating an X-ray, on a target are provided. The generation, inspector and the method have been developed by turning an attention on the fact that convergence conditions of an electron beam has a close relationship with a temperature on a surface of an X-ray tube target. The method comprises the steps of measuring the temperature changes at real time by a temperature sensor 14 and automatically controlling a current value of a focusing coil 6.

Claims

1. An X-ray generator comprising:

an energy beam generation source;

a target for generating an X-ray by being irradiated by an energy beam generated from said energy beam generation source, said target comprising a first metal layer having a predetermined pattern and a second metal layer having a predetermined pattern connected to said first metal layer through a hot contact point formed in an insulation layer, said target further comprising an integrally-formed thermocouple temperature sensor within said first metal layer and said second metal layer;

a convergence lens for converging the energy beam proceeding to said target from said energy beam generation source;

a temperature sensor for detecting a temperature near irradiation of said energy beam on said target; and

a control device for controlling a convergence degree of said energy beam on the target by use of said convergence lens, based on a temperature signal detected by said temperature sensor.

2. The X-ray generator as set forth in claim 1, wherein said energy beam generation source is an electron beam generation source.

3. The X-ray generator as set forth in claim 1, wherein said target comprises a tungsten layer and a beryllium layer.

4. The X-ray generator as set forth in claim 1, wherein said convergence lens is a focusing coil.

5. The X-ray generator as set forth in claim 1, wherein said control device controls a current value to be given to said focusing coil based on time differentiation of the temperature detected by said temperature sensor.

6. An X-ray inspector, comprising an X-ray generator including an X-ray generation portion for generating an X-ray, and an X-ray image sensor having an X-ray detection surface for detecting an image of an X-ray transmission light irradiated on an object to be inspected from said X-ray generation portion;

which detects an image by enlarging the core portion of said object to be inspected at an enlarging magnification determined based on a positional relationship of said X-ray generation portion and the object to be inspected;

wherein;

said X-ray generator comprises;

an energy beam generation source,

a target for generating an X-ray by being irradiated by an energy beam generated from said energy beam generation source, said target comprising a first metal layer having a predetermined pattern and a second metal layer having a predetermined pattern connected to said first metal layer through a hot contact point formed in an insulation layer, said target further comprising, an integrally-formed thermocouple temperature sensor within said first metal layer and said second metal layer,

a convergence lens for converging the energy beam passing to said target from said energy beam generation source,

a temperature sensor for detecting a temperature near an irradiation point of said energy beam on said target, and

a control device for controlling a convergence degree of said energy beam on the target by use of said convergence lens, based on a temperature signal detected by said temperature sensor.

7. An X-ray generation method comprising:

detecting a temperature near an irradiation point of an energy beam on a target, the target comprising a first metal layer having a predetermined pattern and a second metal layer having a predetermined pattern connected to the first metal layer through a hot contact point formed in an insulation layer, the target further comprising an integrally-formed thermocouple temperature sensor within the first and second metal layers; and

generating an X-ray by irradiating said energy beam on the target while controlling a convergence degree of said energy beam on the target by use of a convergence lens, based on a signal detected by said detecting the temperature.