JPH032699A - X-ray device - Google Patents

Abstract

PURPOSE:To obtain an extremely intensified and monochromatized X-ray by multiplying a plurality of X-rays that are a plurality of X-rays emitted from a plurality of X-ray generating parts and applied to an asymmetrically cut monochrometer to be monochromatized. CONSTITUTION:A heating electric current and a negative high voltage are fed simultaneously to filaments F1, F2 and 3, and therewith electrons are discharged from each filaments F1, F2 and F3, and are accelerated thereby. As the result, X-rays X1, X2 and X3 progressing to the same direction are emitted from each region E1, E2 and E3. These X-rays X1, X2 and X3 are projected into an asymmetrically cut monochrometer 2 and an X-ray X which is a very narrow single beam monochromatized to a direction having very small angle to a cut surface of the asymmetically cut monochrometer 2, is reflected. In this way, the X-ray X which is monochromatized and is strongly intensified, can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to
Regarding line equipment.

[Prior Art] In precise X-ray diffraction measurements, X-rays generated by an X-ray target are made monochromatic using a crystal monochromator or the like.

Generally, the intensity of this monochromated X-ray is significantly lower than that of the original X-ray. This is because the reflectance of the crystal monochromator used for monochromating is low.

Therefore, conventionally, when performing measurements with a high S/N ratio using monochromatic X-rays, it has been common to use powerful X-ray generators.

By the way, as an X-ray generator capable of generating powerful X-rays, a so-called rotating anticathode X-ray generator is known (see, for example, Japanese Patent Publication No. 52-46679). This makes it possible to obtain powerful X-rays by circulating cooling water through a cylindrical target while rotating it and irradiating the outer peripheral surface with electron beams. According to this, it is possible to obtain extremely strong X-rays, so that a certain level of intensity can be maintained even after being made monochromatic with a crystal monochromator.

[Problems to be Solved by the Invention] However, in order to obtain powerful X-rays above a certain level with the above-mentioned rotating anticathode X-ray device, it is necessary to increase the diameter of the cylindrical target or increase the rotation speed. There is a need to increase the cooling properties by using the following methods, but each has its limits. Moreover,
Increasing the diameter of a rotating target is extremely difficult in practice due to various design problems. That is, if we take into consideration the things that are necessarily required to increase the diameter of the rotating target, even if the diameter is slightly increased, the device will become significantly larger. Therefore, in the method of obtaining monochromatic X-rays using a conventional rotating anticathode / There was a certain limit to improving the N ratio.

The present invention has been made against the above-mentioned background, and is an X-ray device that can obtain monochromatic X-rays with significantly higher intensity than conventional ones using a relatively small X-ray generator. The purpose is to provide the following.

[Means for Solving the Problems] The present invention solves the above problems by having the following configuration.

A plurality of X-ray generators capable of extracting a plurality of X-ray beams that are close to each other and traveling in the same direction, and a plurality of X-ray beams that are incident from a direction forming a specific angle with the surface (cut surface). and an asymmetric cut monochromator that reflects only the X-rays having a specific wavelength among the X-rays included in the X-ray beam in a direction forming a slight angle with the cut surface.

[Function] In the above configuration, a plurality of X-ray beams that are close to each other and proceed in the same direction are taken out from the plurality of X-ray generating units, and the surfaces (cut surfaces) of the X-ray beams are taken out to the asymmetric cut monochromator. When the beam is incident from a direction forming a specific angle with the cut surface, only the X-rays having a specific wavelength among the X-rays included in the X-ray beam can be extracted from the direction forming a slight angle with the cut surface. This results in
Monochromatic X-rays can be obtained.

In this case, the monochromatic X-ray beam taken out from a direction making a slight angle with the cut surface has many areas overlapping with each other when reflected from the cut surface, becoming one extremely narrow beam. That is, a plurality of X-rays, each of which is made monochromatic of the plurality of X-ray beams incident on the cut surface, overlap with each other to form one beam.

Therefore, the obtained monochromatic X-rays are powerful and have approximately the same intensity as a plurality of monochromatic X-rays superimposed.

Here, since each of the plurality of X-ray generators may be relatively small, the The line generating section can be made extremely small and inexpensive.

For example, in the above-mentioned X-ray generating section, the tube current is 250 mA.
When monochromatic X-rays are obtained using two rotating anticathode X-ray generators, the intensity of the monochromatic X-rays can be increased by a tube current of 500
It corresponds to the intensity obtained using a rotating anticathode X-ray generator of mA.

A rotating anticathode X-ray generator with a tube current of 250 mA usually
The rotating anode cathode has a diameter of about 100 mm and is relatively easy to design, but the tube current is about 500 mm.
mA rotating anticathode X-ray generator requires a target diameter of 150 mm or more, making it extremely large-scale, difficult to design and manufacture, and the production cost is higher than that of the 250 mA tube current. It is extremely expensive, almost three times as expensive.

[Embodiment] FIG. 1 is a partial cross-sectional view showing the configuration of a first embodiment of the present invention. The first embodiment will be described in detail below with reference to FIG.

In FIG. 1, reference numeral 1 indicates an X-ray target, reference numeral F1.
F2. F3 is the first, second, and third filament, respectively, and 2 is an asymmetric cut monochromator.

The X-ray target 1 is made of Cu, Mo, or other metal, and although not shown, cooling water is allowed to flow inside. Note that the X-ray target 1 is grounded and maintained at zero potential.

The filament F1. F2. F3 is made of tungsten or the like, and although not shown, is capable of passing a heating current through each, and is also capable of applying a negative high voltage (several tens of Kv).

The X-ray target 1 and the filaments F1, F2, and F3 constitute a plurality of X-ray generating sections in the present invention, and are formed at a predetermined angle (usually,
Three X-rays X1 traveling in the same direction (several degrees)
, X2'+X3 can be taken out.

The asymmetric cut monochromator 2 is made of Si.

It is made of crystals such as SiO2 or LiF, and is cut from a direction forming a specific angle (γ) with a specific lattice plane of these crystals, such as the (001) plane. Then, by making X-rays containing multiple wavelength components incident on the cut surface (surface) from a specific incident direction (direction θ with the cut surface), monochromatic X-rays can be extracted in a direction that satisfies Bragg's diffraction conditions. This is how it was done.

In this case, if the angle of reflection from the cut surface is selected to form an extremely small angle (Δθ) with the cut surface, even if the incident X-ray beam is relatively wide, it can be monochromatic. The width of the reflected X-rays is extremely narrow. That is, this means that even if the incident X-ray beam consists of a plurality of X-ray beams, the monochromatic reflected X-rays will be emitted as one beam.

In the above configuration, now the filament F1. F
, 2, When a heating current and a negative high voltage are passed through F3, electrons fly out from each of the filaments Fi, F2, and F3 and are accelerated, as shown by arrow e in the figure, and the X-ray target 1 each of said filaments F1
．． X-ray generation area E1 facing F2 and F3. F2,
Collision with F3.

As a result, each area E1. E2. From E3, X-rays X1 traveling in the same direction as shown in FIG.
X2 and X3 are emitted.

These X-rays X1, X2, and X3 are incident on the asymmetrical cut monochromator 2 at an incident angle; θ), and in a direction that forms an extremely small angle (=reflection angle: Δθ) with the cut surface (surface) of the asymmetrical cut monochromator 2. It reflects X-rays, which are a single thin monochromatic beam. That is, this makes it possible to obtain monochromatic X-rays.

According to the embodiment described above, the obtained monochromatic X-rays X are obtained by overlapping a plurality of X-rays obtained by monochromating each of the plurality of X-ray beams generated from the plurality of X-ray generating units. Therefore, its intensity is approximately equivalent to that of multiple monochromatic X-rays superimposed.

Here, since each of the plurality of X-ray generators may be relatively small, the The line generating section can be made extremely small and inexpensive.

(Second example) FIG. 2 is a partial sectional view showing the configuration of the second embodiment.

As shown in FIG. 2, in this embodiment, the X-ray targets constituting a plurality of X-ray generating sections are divided into separate and independent targets 201, 202, and 203, respectively. The rest of the structure is the same as that of the first embodiment.

This embodiment also provides the same advantages as the first embodiment.

In each of the above embodiments, an example is shown in which one asymmetrical cut monochromator is used, but if the width of the incident X-ray beam is wide, multiple asymmetrical cut monochromators whose cut surfaces are aligned on the same plane may be A meter may also be used.

[Effects of the Invention] As detailed above, the present invention allows a plurality of X-rays emitted from a plurality of X-ray generating units to be incident on an asymmetric cut monochromator, so that each of the plurality of incident X-ray beams is A plurality of monochromatic X-rays are overlapped, thereby making it possible to obtain powerful monochromatic X-rays having an intensity equivalent to that of a plurality of monochromatic X-rays superimposed.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing the configuration of an X-ray apparatus according to a first embodiment of the present invention, and FIG. 2 is a partial sectional view showing the configuration of an X-ray apparatus according to a second embodiment of the present invention. 1... X-ray target, 2... Asymmetric cut monochromator, Fl, F2. F3...first, second and third
filament, El, E2. E3...X-ray generation area, Xl, X2, X3...X-ray beam, X...monochromatic X-ray beam. Applicant Mac Science Co., Ltd.

Claims (1)

[Scope of Claims] A plurality of X-ray generators capable of extracting a plurality of X-ray beams that are close to each other and proceed in the same direction; an asymmetrical cut monochromator that receives an X-ray beam and reflects only the X-rays having a specific wavelength among the X-rays contained in the X-ray beam in a direction forming a slight angle with the cut surface. X-ray equipment.