Spectral element

Abstract

A spectroscopic element, comprising: a spectroscopic crystal (10) for spectroscopic X-rays; a first support layer (11) supporting the spectroscopic crystal (10); and a second support layer (12) supporting the first support layer (11), wherein the first support layer (11) has a thermal expansion coefficient greater than that of the spectroscopic crystal (10), and the second support layer (12) has a thermal expansion coefficient smaller than that of the first support layer (11) and has a rigidity greater than that of the first support layer (11).

Description

Technical Field

[0001] The present invention relates to a light splitting element. Background Art

[0002] For a long time, spectroscopic elements used in fluorescent X-ray analysis devices and the like have been known. For example, Japanese Patent Publication No. 2011-117891 (hereinafter referred to as "Patent Document 1") discloses a spectroscopic element having a spectroscopic crystal and a heat-conducting component. The spectroscopic crystal is composed of single crystal silicon or single crystal germanium. The heat-conducting component is composed of an inorganic material containing at least one of carbon nanofibers and carbon nanotubes. The thermal conductivity of the heat-conducting component is greater than the thermal conductivity of the spectroscopic crystal. Therefore, the heat generated in the X-ray irradiation area of ​​the spectroscopic crystal is conducted to the heat-conducting component, and the temperature distribution of the spectroscopic crystal is thus uniformized.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-117891 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] In the spectroscopic element described in Patent Document 1, the difference between the thermal expansion coefficient of the spectroscopic crystal and the thermal expansion coefficient of the heat-conducting member may cause strain in the spectroscopic crystal, thereby reducing the spectroscopic performance. For example, when the thermal expansion coefficient of the heat-conducting member is larger than the thermal expansion coefficient of the spectroscopic crystal, the heat-conducting member bends in a manner that protrudes toward the opposite side of the spectroscopic crystal, thereby causing strain in the spectroscopic crystal.

[0008] An object of the present invention is to provide a spectroscopic element capable of reducing strain generated in a spectroscopic crystal.

[0009] Solutions for solving problems

[0010] The first embodiment of the present invention relates to a spectroscopic element, comprising: a spectroscopic crystal for spectroscopic X-rays; a first support layer for supporting the spectroscopic crystal; and a second support layer for supporting the first support layer, wherein the first support layer has a thermal expansion coefficient greater than that of the spectroscopic crystal, and the second support layer has a thermal expansion coefficient smaller than that of the first support layer and has a rigidity greater than that of the first support layer.

[0011] Effects of the Invention

[0012] The spectroscopic element includes a second support layer having a smaller thermal expansion coefficient than that of the first support layer and having a greater rigidity than that of the first support layer, so that the first support layer can be prevented from bending in a manner protruding toward the second support layer due to the difference between the thermal expansion coefficient of the spectroscopic crystal and the thermal expansion coefficient of the first support layer. Therefore, the strain generated in the spectroscopic crystal is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a front view schematically showing the structure of a spectroscopic element according to one embodiment of the present invention.

[0014] Figure 2 To show Figure 1 A perspective view of a 1 / 4 object model of the beam splitter element is shown.

[0015] Figure 3 This is a perspective view showing a deformed state of the light-splitting element of Example 1.

[0016] Figure 4 This is a perspective view showing a deformed state of the spectroscopic element of Example 2.

[0017] Figure 5 It is a perspective view showing a deformed state of the model of the comparative example. DETAILED DESCRIPTION

[0018] The embodiments of the present invention are described with reference to the accompanying drawings. It should be noted that in the drawings referred to below, the same or corresponding components are marked with the same reference numerals.

[0019] Figure 1 FIG. 1 is a perspective view schematically showing the structure of a spectroscopic element according to one embodiment of the present invention. Figure 1 As shown, the spectroscopic element 1 includes a spectroscopic crystal 10 , a first supporting layer 11 , and a second supporting layer 12 .

[0020] The spectroscopic crystal 10 is configured to split X-rays. The spectroscopic crystal 10 is composed of, for example, a single crystal of germanium, a single crystal of lithium fluoride, or a single crystal of silicon. The spectroscopic crystal 10 has an irradiated surface 10S1 irradiated with X-rays and an opposite surface 10S2 formed on the opposite side of the irradiated surface 10S1.

[0021] The first support layer 11 supports the spectroscopic crystal 10. The first support layer 11 is formed in a flat plate shape. The first support layer 11 has a first support surface 11S1 in contact with the opposite surface 10S2 of the spectroscopic crystal 10, and a first back surface 11S2 formed on the opposite side of the first support surface 11S1. The first support surface 11S1 is bonded to the opposite surface 10S2 of the spectroscopic crystal 10 by an adhesive.

[0022] The first support layer 11 is preferably composed of a light element (e.g., an element lighter than titanium) to suppress the generation of high-energy stray rays (X-rays different from the X-rays separated by the spectroscopic crystal 10) from the first support surface 11S1 when the spectroscopic crystal 10 is irradiated with X-rays. The first support layer 11 has a thermal expansion coefficient greater than that of the spectroscopic crystal 10. In the present embodiment, the first support layer 11 is composed of aluminum. The thickness of the first support layer 11 is preferably set to be greater than 0.1 mm and less than 100 mm, and more preferably set to be greater than 1 mm and less than 7 mm.

[0023] The second supporting layer 12 supports the first supporting layer 11. The second supporting layer 12 is formed in a flat plate shape. The second supporting layer 12 has a second supporting surface 12S1 in contact with the first rear surface 11S2 of the first supporting layer 11 and a second rear surface 12S2 formed on the opposite side of the second supporting surface 12S1.

[0024] The second support layer 12 has a smaller thermal expansion coefficient than the first support layer 11 and has a greater rigidity than the first support layer 11. In the present embodiment, the second support layer 12 is made of stainless steel (SUS). The thickness of the second support layer 12 may be smaller than the thickness of the first support layer 11. The thickness of the second support layer 12 is preferably set to 0.1 mm or more and 100 mm or less, and more preferably set to 1 mm or more and 5 mm or less.

[0025] The spectroscopic element 1 described above is preferably used in an X-ray analyzer, for example, a wavelength dispersive fluorescence X-ray analyzer (WDX) disclosed in Japanese Patent Application Laid-Open No. 2017-223638.

[0026] Then, refer to Figure 2 to Figure 5 The simulation results of the example of the spectroscopic element 1 according to the above-mentioned embodiment and a comparative example thereof will be described.

[0027] Figure 2 A 1 / 4 object model of the spectroscopic element 1 is shown. Figure 2 The point A shown in FIG. 1 is the center of the illuminated surface 10S1 of the spectroscopic crystal 10 .

[0028] Figure 3 In the embodiment 1 shown, the spectroscopic crystal 10 is made of germanium and has a thickness of 1 mm. The first support layer 11 is made of aluminum and has a thickness of 4 mm. The second support layer 12 is made of stainless steel (SUS304) and has a thickness of 3 mm.

[0029] Figure 4 In the illustrated embodiment 2, the spectroscopic crystal 10 and the first support layer 11 are the same as those in the embodiment 1. The second support layer 12 is made of stainless steel (SUS316) and has a thickness of 3 mm.

[0030] Figure 5 In the comparative example shown, the spectroscopic crystal 10 and the first supporting layer 11 are the same as those in Example 1, but the comparative example does not include the second supporting layer 12 .

[0031] A simulation was performed to give a temperature rise of 1.5° C. to Example 1, Example 2, and Comparative Example. Figures 3 to 5 In FIG. 1 , the outer shape of the model when the temperature is increased by 1.5° C. is shown by a solid line, and the outer shape of the model in the state before the temperature increase is shown by a two-dot chain line.

[0032] like Figure 3 As shown in FIG. 1 , the warp d1 of the light-splitting crystal 10 in Example 1 is 0.1 μm. Figure 4 As shown in FIG. 2 , the warp d2 of the light-splitting crystal 10 in Example 2 is 0.02 μm. Figure 5 As shown, the warp d3 of the spectroscopic crystal 10 in the comparative example is 1.2 μm. It should be noted that “warp” refers to the distance between the outer end of the irradiated surface 10S1 in the X-axis direction and the center A in the direction parallel to the Y-axis of each model.

[0033] As described above, the spectroscopic element 1 of the present embodiment includes the second support layer 12 having a smaller thermal expansion coefficient than the first support layer 11 and having a greater rigidity than the first support layer 11, and therefore, it is possible to suppress the first support layer 11 from bending in a manner protruding toward the second support layer 12 due to the difference between the thermal expansion coefficient of the spectroscopic crystal 10 and the thermal expansion coefficient of the first support layer 11. Therefore, the strain generated in the spectroscopic crystal 10 is reduced.

[0034] In addition, it should be understood that the embodiments disclosed this time are illustrative in all aspects and are not restrictive. The scope of the present invention is disclosed not by the description of the above embodiments but by the claims, and includes all changes within the meaning and scope equivalent to the claims.

[0035] [Way]

[0036] Those skilled in the art will appreciate that the above-mentioned multiple exemplary embodiments are specific examples of the following aspects.

[0037] (Item 1) The above-mentioned spectroscopic element in one embodiment comprises: a spectroscopic crystal for spectroscopic X-rays; a first support layer for supporting the above-mentioned spectroscopic crystal; and a second support layer for supporting the above-mentioned first support layer, wherein the above-mentioned first support layer has a thermal expansion coefficient larger than the thermal expansion coefficient of the above-mentioned spectroscopic crystal, and the above-mentioned second support layer has a thermal expansion coefficient smaller than the thermal expansion coefficient of the above-mentioned first support layer and has a rigidity greater than the rigidity of the above-mentioned first support layer.

[0038] The spectroscopic element described in item 1 includes a second support layer having a smaller thermal expansion coefficient than that of the first support layer and having a greater rigidity than that of the first support layer, so that the first support layer can be prevented from bending in a manner protruding toward the second support layer due to the difference between the thermal expansion coefficient of the spectroscopic crystal and the thermal expansion coefficient of the first support layer. Therefore, the strain generated in the spectroscopic crystal is reduced.

[0039] (Item 2) In the spectroscopic element described in Item 1, the thickness of the first supporting layer is preferably 1 mm or more.

[0040] According to the spectroscopic element described in item 2, even if stray rays (X-rays different from the X-rays separated by the spectroscopic crystal) are generated from the surface of the second support layer when the spectroscopic crystal is irradiated with X-rays, at least a part of the stray rays is absorbed by the first support layer. Therefore, the analysis accuracy of the X-rays separated by the spectroscopic element is improved.

[0041] (Item 3) In the spectroscopic element described in Item 1 or Item 2, it is preferred that: the above-mentioned spectroscopic crystal is composed of germanium or lithium fluoride, the above-mentioned first supporting layer is composed of aluminum, and the above-mentioned second supporting layer is composed of stainless steel.

[0042] According to the spectroscopic element described in item 3, since the first supporting layer is made of aluminum, the first supporting layer can be manufactured at a relatively low cost, and the first supporting layer has high processability, and the generation of stray rays from the first supporting layer can also be reduced.

[0043] Description of Reference Numerals

[0044] 1 spectroscopic element, 2 support, 3 excitation source, 4 slit, 5 X-ray linear sensor, 10 spectroscopic crystal, 10S1 irradiated surface, 10S2 opposite surface, 11 first supporting layer, 11S1 first supporting surface, 11S2 first back surface, 12 second supporting layer, 12S1 second supporting surface, 12S2 second back surface, 100 X-ray spectrometer, S sample.

Claims

1. A spectroscopic element, comprising: Spectroscopic crystals for splitting X-rays; a first supporting layer supporting the spectroscopic crystal; and a second supporting layer supporting the first supporting layer, The first support layer has a thermal expansion coefficient greater than that of the spectroscopic crystal. The second support layer has a thermal expansion coefficient smaller than that of the first support layer and has a rigidity greater than that of the first support layer. The spectroscopic crystal is composed of germanium or lithium fluoride. The first supporting layer is composed of aluminum, The second supporting layer is made of stainless steel.

2. The spectroscopic element according to claim 1, wherein: The thickness of the first support layer is greater than 1 mm.

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