Method for measuring focal position of micro-focal spot X-ray tube

Abstract

The invention mainly relates to the technical field of X-ray tubes, and provides a method for measuring the focus position of a micro-focal-spot X-ray tube, which mainly comprises a micro-focal-spot X-ray tube to be measured 1, a capillary X-ray convergent lens 2, a high-precision five-dimensional displacement table and computer control system 3, a gas proportional counter tube and high-voltage power supply 4, a digital counter 5 and the like. The position and angle of the capillary X-ray lens 2 in the space are adjusted by controlling the high-precision five-dimensional displacement table 3, when the digital counter 5 displays the maximum count, the central position of the front focus of the capillary X-ray lens is the central position of the focus of the micro-focal spot X-ray tube, and when the digital counter 5 displays the maximum count, the central position of the front focus of the capillary X-ray lens is the central position of the focus of the micro-focal spot X-ray tube. And the angle of the central axis of the capillary X-ray lens is the central axis of the X-ray emitting angle of the micro-focal spot X-ray tube.

Description

Technical Field

[0001] The invention relates to the technical field of X-rays, and in particular to a method for measuring the focal position of a micro-focus X-ray tube. Background Art

[0002] Micro-focus X-ray tube is an important electronic device. It has important application prospects in the fields of X-ray industrial CT, medical imaging, etc. Therefore, it is of great significance to develop high-quality micro-focus X-ray tubes. However, since the focal spot of micro-focus X-ray tubes is very small, even reaching a size of several hundred nanometers, there are errors in the industrial production and assembly process, which causes the position of the micro-focus X-ray tube after leaving the factory to deviate from the center position of the flange of the X-ray tube beryllium window or tube sleeve, and the X-ray emission angle also has a certain degree of deviation. Therefore, measuring the focal position of the micro-focus X-ray is of great significance for the assembly of the instrument and the improvement of the quality of the micro-focus X-ray tube. Summary of the invention

[0003] In view of the deficiencies of the existing technology, the present invention provides a method for measuring the focal position of a micro-focus X-ray tube. The capillary X-ray converging lens is fixed on a high-precision five-dimensional displacement stage by utilizing the characteristic of the capillary X-ray lens in converging X-rays. The position of the capillary X-ray lens fixed on the high-precision five-dimensional displacement stage is adjusted by the high-precision five-dimensional displacement stage so that the center of the focal point of the micro-focus X-ray tube to be measured coincides with the center of the front focal point of the capillary X-ray lens; the central axis of the X-ray beam emitted by the micro-focus X-ray tube to be measured coincides with the central axis of the capillary X-ray lens. The X-ray beam excited from the micro-focus X-ray tube to be measured is transmitted by total reflection on the inner wall of the hollow capillary, and the gas proportional counter tube receives the converged X-ray beam. The intensity of the converged X-ray beam is output through a digital counter connected to the proportional counter tube. When the particle count on the digital counter reaches the maximum value, the center position of the front focal length of the capillary X-ray lens is the center position of the focus of the micro-focus X-ray tube, and the angle of the central axis of the capillary X-ray lens is the central axis of the X-ray emission angle of the micro-focus X-ray tube.

[0004] The present invention provides a method for measuring the focal position of a micro-focus X-ray tube, the method mainly comprising: a micro-focus X-ray tube to be measured 1, a capillary X-ray converging lens 2, a high-precision five-dimensional displacement stage and a computer control system 3, a gas proportional counter and a high-voltage power supply 4, a digital counter 5, etc.;

[0005] The converging capillary X-ray lens is composed of millions of hollow capillary glass tubes fused together at high temperature, and has the function of converging the X-ray beam at the front focal position at the rear focal point after being transmitted by total reflection on the inner wall of the hollow capillary glass tube.

[0006] Furthermore, the high-precision five-dimensional translation stage can move in five directions of space with a step distance of 0.5 micrometers through a computer control program;

[0007] Furthermore, the gas proportional counter tube receives the X-ray beam converged by the capillary X-ray lens, and the X-ray excites the gas in the proportional counter tube to generate ionization. The ionized particles move from the positive and negative electrodes under the action of high voltage, and the number of particles is displayed by the counter;

[0008] Furthermore, the digital counter receives the signal from the proportional counter tube and displays it. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the technical drawings required in the current technical description. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0010] Figure 1 A schematic diagram of the structure of a method for measuring the focal position of a micro-focus X-ray tube provided by an embodiment of the present invention; DETAILED DESCRIPTION

[0011] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0012] The embodiments of the present application will be described below in conjunction with the accompanying drawings, but the present invention is not limited thereto.

[0013] like Figure 1 As shown, a method for measuring the focal position of a micro-focus X-ray tube provided by an embodiment of the present invention is provided. The method for measuring the focal position of a micro-focus X-ray tube comprises a micro-focus X-ray tube 1 to be measured, a capillary X-ray converging lens 2, a high-precision five-dimensional translation stage and a computer control system 3, a gas proportional counter and a high-voltage power supply 4, a digital counter 5, etc.

[0014] The X-ray beam excited by the micro-focus X-ray tube 1 to be measured adjusts the position and angle of the capillary X-ray lens 2 in the five-dimensional direction of space through a high-precision five-dimensional displacement stage and a computer control system 3, so that the center of the focal spot of the micro-focus X-ray tube to be measured coincides with the center of the front focal length of the capillary X-ray lens, and the central axis of the angle of the X-ray beam emitted by the micro-focus X-ray tube to be measured coincides with the central axis of the capillary X-ray lens, and the intensity of the X-ray beam converged by the capillary X-ray lens is displayed through a gas proportional counter 4 and a digital counter 5. When the digital counter 5 displays the maximum count, the center position of the front focal point of the capillary X-ray lens is the center position of the focus of the micro-focus X-ray tube, and the angle of the central axis of the capillary X-ray lens is the center line of the X-ray emission angle of the micro-focus X-ray tube.

[0015] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for measuring the focal position of a micro-focus X-ray tube, characterized in that: The system comprises a micro-focus X-ray tube to be tested (1), a capillary X-ray converging lens (2), a high-precision five-dimensional displacement stage and a computer control system (3), a gas proportional counter tube and a high-voltage power supply (4), and a digital counter (5). The micro-focus X-ray tube (1) to be tested is used to generate an X-ray beam, and the capillary X-ray converging lens (2) is fixed on a high-precision five-dimensional displacement stage (3). The computer control software of the high-precision five-dimensional displacement stage (3) is used to adjust the spatial position of the five-dimensional displacement stage so that the center of the focus of the micro-focus X-ray tube (1) to be tested coincides with the center of the front focus of the capillary X-ray converging lens (2); when the central axis of the X-ray emission of the micro-focus X-ray tube (1) to be tested coincides with the central axis of the capillary converging lens (2). When the count displayed by the digital counter (5) connected to the gas proportional counter tube and the high-voltage power supply (4) is the maximum, the central position of the front focus of the capillary X-ray converging lens is the central position of the focus of the micro-focus X-ray (1) to be tested, and the central axis angle of the capillary X-ray converging lens (2) is the central axis of the X-ray emitted by the micro-focus X-ray tube to be tested.

2. The capillary X-ray converging lens (2) according to claim 1 is fixed on a high-precision five-dimensional translation stage (3), and is made of millions of hollow capillary glass tubes drawn at high temperature. The inner diameter of the hollow glass tubes is less than 10 microns, and has a front focus for collecting X-rays and a rear focus for converging X-rays.

3. According to the high-precision five-dimensional translation stage and computer control system (3) described in claim 1, the minimum step size of the high-precision five-dimensional translation stage is 0.5 microns, and it moves in five dimensions in space under the control of computer software.

4. According to the gas proportional counter tube and high-voltage power supply (4) described in claim 1, after the gas proportional counter tube receives the X-rays converged by the capillary X-ray lens (2), the gas inside the gas proportional counter tube is ionized, and the particles move toward the positive and negative electrodes of the proportional counter tube under the action of high voltage.

5. The digital counter (5) according to claim 1 is connected to the gas proportional counter tube (4), receives the signal output by the gas proportional counter tube (4) and displays it on the digital counter.

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