Spectrometry method and spectrometer for extreme ultraviolet and x-rays

Abstract

The application provides a spectral separation method and a spectrometer for extreme ultraviolet and X-rays. The spectral separation method for extreme ultraviolet and X-rays comprises the following steps: step S1, obtaining an incident light beam, the incident light beam at least containing the spectrum of the extreme ultraviolet and X-ray waveband; step S2, obtaining a focusing mirror of the spectrometer, the incident light beam is incident into the focusing mirror at a grazing incidence angle, and the focusing mirror converges the incident light beam; step S3, obtaining a conical diffraction grating of the spectrometer, the conical diffraction grating is used for receiving the convergent light output by the focusing mirror and diffracting and separating the incident light beam of different wavebands; and step S4, adjusting the relative position between the focusing mirror and the conical diffraction grating, so that the aberration generated between the focusing mirror and the conical diffraction grating is offset, and the conical diffraction grating outputs a focused light beam. The application solves the problems of low efficiency and complex device in the prior art of spectral separation of extreme ultraviolet and X-rays.

Description

Technical Field

[0001] This invention relates to the field of spectral analysis equipment technology, and more specifically, to a method and spectrometer for spectral separation of extreme ultraviolet and X-rays. Background Technology

[0002] Extreme ultraviolet (EUV) and X-ray sources play a crucial role in scientific exploration and industrial research and development. Currently, numerous synchrotron radiation, free-electron lasers, laser plasma sources, and high-harmonic lasers have been constructed worldwide to generate EUV and X-ray lasers for research in materials science, biochemistry, and medicine. During the use of EUV and X-ray sources, it is often necessary to detect the spectrum of the source or to separate monochromatic laser light from multiple wavelengths for application. For example, transient spectral analysis experiments require recording the dynamic changes of harmonic spectra over time, while angle-resolved electron spectroscopy and coherent diffraction imaging require monochromatic and focused beams. Therefore, in many application scenarios, EUV and X-ray sources typically require technical solutions to problems such as spectral detection, spectral monochromatic separation, and beam focusing.

[0003] The electromagnetic wavelengths corresponding to extreme ultraviolet (EUV) and X-rays are very short (UV: 10-121 nm, X-rays: 0.01-10 nm). Various optical materials generally exhibit strong absorption of electromagnetic waves with wavelengths less than 100 nm, making refractive dispersion and focusing schemes (such as prisms and lenses) difficult to apply in the EUV and X-ray bands. Therefore, spectrometers in the EUV and X-ray bands typically use reflective diffraction gratings to separate the spectra, and concave mirrors are often used for beam focusing, employing grazing incidence to improve reflectivity. However, current spectrometers suffer from various problems in spectral analysis. For example, one existing technology proposes a spectrometer that combines a focusing mirror with a diffraction grating. While this structure reduces the number of components used, its overall efficiency is low, approximately 15%. Another existing technology proposes a spectrometer that uses three components to avoid aberrations: two focusing mirrors and one diffraction grating. Although this achieves focused output, it involves too many components, is complex, and difficult to adjust between components, resulting in an overall efficiency of approximately 35%, which is still not ideal.

[0004] In other words, the spectral separation of extreme ultraviolet and X-rays in existing technologies suffers from low efficiency and complex equipment. Summary of the Invention

[0005] The main objective of this invention is to provide a method and spectrometer for spectral separation of extreme ultraviolet (EUV) and X-rays, in order to solve the problems of low efficiency and complex equipment in the existing spectral separation of EUV and X-rays.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for spectral separation of extreme ultraviolet and X-rays is provided, comprising the following steps: Step S1: acquiring an incident beam, the incident beam containing at least the spectra of extreme ultraviolet and X-ray bands; Step S2: acquiring a focusing lens of a spectrometer, causing the incident beam to enter the focusing lens at a grazing incidence angle, the focusing lens converging the incident beam; Step S3: acquiring a conical diffraction grating of the spectrometer, the conical diffraction grating being used to receive the converged light output from the focusing lens and to perform diffraction and spectral separation to separate the incident beams of different bands; Step S4: adjusting the relative position between the focusing lens and the conical diffraction grating so that the aberrations generated between the focusing lens and the conical diffraction grating cancel each other out, while simultaneously causing the conical diffraction grating to output a focused beam.

[0007] Furthermore, in step S2, the focusing lens converges the incident beam and outputs it in the form of reflection; in step S4, the conical diffraction grating separates and outputs the incident beams of different wavelengths in the form of reflection.

[0008] Furthermore, step S4 also includes: step S41: determining the zero-order reflection position of the conical diffraction grating; step S42: adjusting the rotation angle of the focusing lens so that the converging light output by the focusing lens undergoes zero-order reflection on the conical diffraction grating, and so that the focused beam output by the conical diffraction grating is focused on the spectral detection surface of the spectrometer.

[0009] Further, in step S42, the rotation angle of the focusing lens is adjusted so that the diffraction order m of the conical diffraction grating, the wavelength λ of the incident beam, the grating line spacing d of the conical diffraction grating, the angle γ2 of the beam incident on the conical diffraction grating, the elevation angle α of the beam incident on the conical diffraction grating, and the elevation angle β of the focused beam output by the conical diffraction grating satisfy the following: mλ / d=sinγ2(sinα+sinβ).

[0010] Furthermore, in step S42, the focusing mirror has a rotational central axis that is parallel to the conical diffraction grating.

[0011] Furthermore, in step S2, the focusing lens is a tire mirror.

[0012] Furthermore, in step S2, the focusing lens is an ellipsoidal lens.

[0013] Further, in step S2, the incident beam enters the focusing lens at a first grazing incidence angle, and in step S3, the converging light output from the focusing lens enters the conical diffraction grating at a second grazing incidence angle, wherein the first grazing incidence angle is equal to the second grazing incidence angle; or the first grazing incidence angle is not equal to the second grazing incidence angle.

[0014] Further, in step S3, the density of the conical diffraction grating is set to be in the range of greater than or equal to 200 lines / mm and less than 500 lines / mm; or the density of the conical diffraction grating is set to be in the range of greater than or equal to 500 lines / mm and less than or equal to 5000 lines / mm.

[0015] Furthermore, in step S1, the wavelength range of the incident beam satisfies greater than or equal to 0.1 nm and less than or equal to 200 nm.

[0016] Furthermore, in step S42, the diameter of the focused beam received on the spectral detection surface is in the range of greater than or equal to 1 micrometer and less than or equal to 1000 micrometers.

[0017] According to another aspect of the present invention, a spectrometer is provided, which is the spectrometer described above. The spectrometer includes at least a light source, a focusing lens, and a conical diffraction grating along the optical path transmission direction. The light source is capable of emitting at least an extreme ultraviolet beam and an X-ray beam. The focusing lens is used to receive the beam emitted by the light source, focus the beam, and reflect it to the conical diffraction grating. The conical diffraction grating is used to receive the beam from the focusing lens and perform diffraction to separate beams of different wavelengths and project them onto the spectral detection surface of the spectrometer.

[0018] According to the technical solution of this invention, a method for spectral separation of extreme ultraviolet and X-rays includes the following steps: Step S1: Acquire an incident beam, the incident beam containing at least the spectra of extreme ultraviolet and X-ray bands; Step S2: Acquire the focusing lens of the spectrometer, so that the incident beam enters the focusing lens at a grazing incidence angle, and the focusing lens converges the incident beam; Step S3: Acquire the conical diffraction grating of the spectrometer, the conical diffraction grating is used to receive the converged light output from the focusing lens and perform diffraction to separate the incident beams of different bands; Step S4: Adjust the relative position between the focusing lens and the conical diffraction grating so that the aberrations generated between the focusing lens and the conical diffraction grating cancel each other out, and at the same time make the conical diffraction grating output a focused beam.

[0019] This application utilizes only two devices—a focusing lens and a conical diffraction grating—to achieve diffraction and spectral separation of a mixed incident beam of extreme ultraviolet (EUV) and X-rays. This separates the EUV and X-ray beams and focuses them onto the spectral detection surface of the spectrometer, saving on optical components, simplifying the structure, reducing costs, and improving beam transmission efficiency. By adjusting the relative positions of the focusing lens and the conical diffraction grating, aberrations generated between them are canceled out, while the conical diffraction grating outputs a focused beam. This configuration allows for adjustable relative positions, ensuring that the converging light from the focusing lens enters the conical diffraction grating under the desired diffraction conditions. Thus, the conical diffraction grating achieves diffraction and spectral separation while simultaneously outputting a focused beam, and aberrations generated between the two components are canceled out, improving overall efficiency while eliminating aberrations. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 A flowchart of an optional embodiment of the spectral separation method for extreme ultraviolet and X-rays is shown;

[0022] Figure 2 An optical path analysis diagram of a spectrometer in the prior art is shown;

[0023] Figure 3 An optical path analysis diagram of another spectrometer in the prior art is shown;

[0024] Figure 4 An optical path diagram of a spectrometer according to an alternative embodiment of the present invention is shown;

[0025] Figure 5 A schematic diagram of a spectrometer according to an alternative embodiment of the present invention is shown, in which the focusing lens is a tire mirror.

[0026] The above figures include the following reference numerals:

[0027] 10. Incident beam; 20. Focusing lens; 21. Rotation center axis; 22. Tire mirror; 30. Conical diffraction grating; 40. Spectral detection surface. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0030] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0031] like Figure 2 The diagram shows the optical path analysis of a spectrometer in the prior art. This spectrometer uses a combination of a focusing lens and a variable density grating. The variable density grating employs conventional diffraction technology, requiring fewer components and having a simpler structure. The beam converges linearly in the detector plane, and the spectrum is not tunable. As shown in the diagram, in the two-dimensional plane, the elevation angle of the beam incident on the variable density grating is α, and the elevation angle of the diffracted light is β. For extreme ultraviolet and X-rays, the grazing incidence angle of the conical diffraction grating is smaller, resulting in higher diffraction efficiency than conventional diffraction. Therefore, the diffraction efficiency of this scheme is only about 15%, and the light pulse broadening is about 1 picosecond. For the incident light to be parallel, both conventional diffracted light and conical diffracted light are parallel, resulting in no diffraction aberrations.

[0032] like Figure 3 The diagram shows the optical path analysis of another spectrometer in the prior art. This spectrometer uses three optical components: a first focusing mirror, a conical diffraction grating, and a second focusing mirror, resulting in a complex structure with numerous optical components. The first focusing mirror focuses the mixed beam and outputs parallel light that is reflected to the conical diffraction grating. The conical diffraction grating diffracts and separates the mixed beam into beams of different wavelengths, which are then directed to the second focusing mirror. The light emitted from the conical diffraction grating is also collimated parallel light. The second focusing mirror focuses the separated beams onto the spectral detection surface. Since both the incident and emitted light from the conical diffraction grating are parallel, the diffraction process does not produce additional aberrations. Although this scheme can achieve point focusing and tunable spectrum, its overall efficiency is approximately 35%, and the pulse broadening is approximately 0.1 picoseconds, which is still not ideal. Figure 3 It can be seen that in three-dimensional space, the incident angle of the incident light of the conical diffraction grating is γ and the elevation angle is α, and the exit angle of the outgoing light is γ and the elevation angle is β.

[0033] In summary, due to limitations imposed by dispersive elements and diffraction aberrations, the resolution of a spectrometer is reduced due to these aberrations. To avoid this reduction in spectral resolution, existing technologies employ the two solutions described above. Figure 2To avoid aberrations, the proposed solution uses a variable density grating line period, which increases manufacturing costs. Furthermore, due to the use of traditional diffraction, the diffraction efficiency is only about 15%. Figure 3 The proposed scheme collimates the beam into parallel light before grating diffraction, and then focuses the parallel light after diffraction. The total number of components is three, making the structure relatively complex.

[0034] To address the problems of low efficiency and complex equipment in the spectral separation of extreme ultraviolet (EUV) and X-rays in existing technologies, this invention provides a method and spectrometer for spectral separation of EUV and X-rays.

[0035] like Figure 1 , Figure 4 and Figure 5 As shown, a method for spectral separation of extreme ultraviolet (EUV) and X-rays includes the following steps: Step S1: Acquire an incident beam 10, the incident beam 10 containing at least the spectra of the EUV and X-ray bands; Step S2: Acquire the focusing lens 20 of the spectrometer, so that the incident beam 10 enters the focusing lens 20 at a grazing incidence angle, and the focusing lens 20 converges the incident beam 10; Step S3: Acquire the conical diffraction grating 30 of the spectrometer, the conical diffraction grating 30 is used to receive the converged light output from the focusing lens 20 and perform diffraction to separate the incident beams 10 of different bands; Step S4: Adjust the relative position between the focusing lens 20 and the conical diffraction grating 30 so that the aberrations generated between the focusing lens 20 and the conical diffraction grating 30 cancel each other out, and at the same time make the conical diffraction grating 30 output a focused beam.

[0036] This application utilizes only two devices, a focusing lens 20 and a conical diffraction grating 30, to achieve diffraction and spectral separation of a mixed incident beam 10 of extreme ultraviolet and X-rays. This separates the extreme ultraviolet and X-ray beams and focuses them onto the spectral detection surface 40 of the spectrometer, saving on optical components, simplifying the structure, reducing costs, and improving beam transmission efficiency. By adjusting the relative positions of the focusing lens 20 and the conical diffraction grating 30, aberrations generated between them are canceled out, while the conical diffraction grating 30 outputs a focused beam. This configuration makes the relative positional relationship between the focusing lens 20 and the conical diffraction grating 30 adjustable, allowing the converging light output from the focusing lens 20 to enter the conical diffraction grating 30 under the desired diffraction conditions. Thus, the conical diffraction grating 30 achieves diffraction and spectral separation while outputting a focused beam, and the aberrations generated between the two are canceled out, improving overall efficiency while eliminating aberrations.

[0037] This application proposes a spectral separation method based on conical diffraction technology for beams in the extreme ultraviolet and X-ray bands. The spectrometer employs a conical diffraction scheme with a grating for spectral separation, and a focusing mirror 20, specifically a concave mirror, is used for beam focusing. By adjusting the focusing mirror 20 or the conical diffraction grating 30, the conical diffraction aberrations and the reflection aberrations of the concave mirror can be mutually compensated, achieving single-spectrum monochromatic beam focusing.

[0038] Specifically, in step S2, the focusing lens 20 converges the incident beam 10 and outputs it in the form of reflection; in step S4, the conical diffraction grating 30 separates and outputs the incident beams 10 of different wavelengths in the form of reflection. That is to say, both the focusing lens 20 and the conical diffraction grating 30 are reflective. Since various optical materials generally have strong absorption of electromagnetic waves with wavelengths less than 100nm, this setting avoids the situation where extreme ultraviolet and X-ray light is absorbed when passing through the focusing lens 20 and the conical diffraction grating 30, thus affecting the light transmission efficiency and ensuring the stability of light transmission.

[0039] Specifically, adjusting the relative position between the focusing lens 20 and the conical diffraction grating 30 in step S4 involves adjusting the rotation angle of the focusing lens 20. This includes:

[0040] Step S41: Determine the zero-order reflection position of the conical diffraction grating 30;

[0041] Step S42: Adjust the rotation angle of the focusing lens 20 so that the converging light output by the focusing lens 20 undergoes zero-order reflection on the conical diffraction grating 30, and the focused beam output by the conical diffraction grating 30 is focused onto the spectral detection surface 40 of the spectrometer. The focusing lens 20 can be adjusted in real time. Adjusting the rotation angle of the focusing lens 20 not only achieves the zero-order diffraction effect of the conical diffraction grating 30, but also allows the aberrations generated by the focusing lens 20 and the conical diffraction grating 30 to compensate and cancel each other out. Simultaneously, it allows the conical diffraction grating 30 to output a focused beam, avoiding the need for additional focusing elements. After diffraction and dispersion by the conical diffraction grating 30, beams of different wavelengths are separated in space at different diffraction angles. For a specific wavelength, a beam with a narrow spectral bandwidth can be obtained spatially, compensating for and eliminating aberrations of a specific spectral bandwidth, optimizing the focusing point of the narrow spectral bandwidth beam, and obtaining high spectral resolution. The converging beam generated by the conical diffraction grating 30 has high temporal and spatial coherence. Spectrometers have high efficiency in beam reflection and diffraction, and low signal loss.

[0042] Specifically, the focusing lens 20 has an individual angle adjustment function, which optimizes the spot size of the beam corresponding to a specific wavelength on the spectral detection surface 40 by rotating the focusing lens 20 or a single degree of freedom, so that the desired wavelength is close to the region of zero-order reflection. In one alternative embodiment of this application, the finally separated extreme ultraviolet and X-ray beams are used for static and transient spectral analysis. In another alternative embodiment of this application, the finally separated extreme ultraviolet and X-ray beams are used for static and dynamic imaging applications.

[0043] like Figure 4 As shown, the spectrometer mentioned in the above method includes two core components: a focusing lens 20 and a conical diffraction grating 30. An incident beam 10 with extreme ultraviolet and X-ray wavelengths first illuminates the focusing lens 20. After being focused and reflected by the focusing lens 20, it then enters the conical diffraction grating 30. Through diffraction by the conical diffraction grating 30, the incident beam 10 is separated and emitted in space according to its wavelength. In step S42, the rotation angle Δ of the focusing lens 20 is adjusted so that the diffraction order m of the conical diffraction grating 30, the wavelength λ of the incident beam 10, the grating line spacing d of the conical diffraction grating 30, the angle γ2 of the beam incident on the conical diffraction grating 30, the elevation angle α of the beam incident on the conical diffraction grating 30, and the elevation angle β of the focused beam output from the conical diffraction grating 30 satisfy the following relationship: mλ / d=sinγ2(sinα+sinβ). The diffraction angle of the conical diffraction grating 30 is based on this diffraction formula.

[0044] refer to Figure 4 In the diagram, the light source is a point source, which emits an incident beam 10 with a total divergence angle of 2θ. γ is the grazing incident angle; for the focusing lens 20, the grazing incident angle is γ1; for the conical diffraction grating 30, the grazing incident angle is γ2. Δ is the rotation angle of the focusing lens 20. Adjusting the rotation angle Δ changes the position of a specific wavelength beam on the spectral detection surface 40, achieving spectral tuning. The focusing lens 20 has a rotation central axis 21, which rotates around. The rotation central axis 21 is parallel to the conical diffraction grating 30.

[0045] In one optional embodiment of this application, such as Figure 5 As shown, the focusing lens 20 in step S2 is a tire mirror 22.

[0046] In another optional embodiment of this application, the focusing lens 20 in step S2 is an ellipsoidal lens.

[0047] Specifically, the incident beam 10 enters the focusing lens 20 with a grazing incidence, and the converging light output from the focusing lens 20 also enters the conical diffraction grating 30 with a grazing incidence. In step S2, the incident beam 10 enters the focusing lens 20 with a first grazing incidence angle γ1. In step S3, the converging light output from the focusing lens 20 enters the conical diffraction grating 30 with a second grazing incidence angle γ2. The first grazing incidence angle γ1 is equal to the second grazing incidence angle γ2; or the first grazing incidence angle γ1 is not equal to the second grazing incidence angle γ2. This can be set according to the actual situation.

[0048] Specifically, in step S3, the density of the conical diffraction grating 30 is set to be greater than or equal to 200 lines / mm and less than 500 lines / mm; or the density of the conical diffraction grating 30 is set to be greater than or equal to 500 lines / mm and less than or equal to 5000 lines / mm. In an optional embodiment of this application, the conical diffraction grating 30 has a density greater than or equal to 200 lines / mm, or a density greater than or equal to 500 lines / mm, or a density greater than or equal to 5000 lines / mm. 5000 lines / mm refers to 5000 lines within a 1mm range.

[0049] In step S1, the wavelength range of the incident beam 10 satisfies greater than or equal to 0.1 nm and less than or equal to 200 nm. Of course, the wavelength of the incident beam 10 can also be greater than 200 nm. Preferably, the wavelength range of the incident beam 10 is within the range of greater than or equal to 0.1 nm and less than or equal to 200 nm. In optional embodiments of this application, the incident beam 10 has a wavelength greater than or equal to 0.1 nm; or the incident beam 10 has a wavelength greater than or equal to 1 nm; or the incident beam 10 has a wavelength greater than or equal to 5 nm; or the incident beam 10 has a wavelength greater than or equal to 10 nm; or the incident beam 10 has a wavelength greater than or equal to 100 nm; or the incident beam 10 has a wavelength greater than or equal to 200 nm.

[0050] Specifically, the spectrum of the incident beam 10 is a narrow-band harmonic beam in the extreme ultraviolet and X-ray bands. Alternatively, the spectrum of the incident beam 10 is an isolated harmonic in the extreme ultraviolet and X-ray bands. Or, the spectrum of the incident beam 10 is a supercontinuum harmonic in the extreme ultraviolet and X-ray bands. The pulse width of the incident beam 10 having extreme ultraviolet and X-ray bands is in the range of 100 femtoseconds to 10 attoseconds.

[0051] In step S42, by adjusting the rotation angle of the focusing mirror 20, the diameter of the focused beam received on the spectral detection surface 40 is made to be greater than or equal to 1 micrometer and less than or equal to 1000 micrometers, thereby optimizing the focused beam spot.

[0052] This application also provides a spectrometer, which includes at least a light source, a focusing lens 20, and a conical diffraction grating 30 along the optical path transmission direction. The light source emits an incident beam 10, which includes at least an extreme ultraviolet beam and an X-ray beam. The focusing lens 20 receives the beam emitted by the light source, focuses the beam, and reflects it to the conical diffraction grating 30. The conical diffraction grating 30 receives the beam from the focusing lens 20 and performs diffraction to separate beams of different wavelengths and project them onto the spectral detection surface 40 of the spectrometer. The spectrometer of this application includes only one focusing lens 20 and one conical diffraction grating 30. The focusing lens 20 and the conical diffraction grating 30 can be set separately or combined in the same module, and the focusing lens 20 has an independent angle adjustment function.

[0053] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0054] 1. The transmission efficiency of the extreme ultraviolet spectrometer is improved. The scheme uses a conical diffraction grating 30 to achieve conical diffraction, with an average diffraction efficiency of ≥60%. The reflection efficiency of the concave mirror under grazing incidence conditions is ≥85%. Therefore, the overall efficiency of the spectrometer in this application is estimated to be as high as 50%.

[0055] 2. Wavelength tunable: The position of the light beam on the spectral detection surface 40 of the spectrometer can be continuously adjusted by adjusting the reflection of the focusing lens 20, thus achieving spectral tuning.

[0056] 3. High spectral resolution: The conical diffraction aberration and the reflection aberration of the focusing lens 20 can compensate for each other. After the spectrum is separated by the conical diffraction grating 30, the single-spectral beam will converge into a point on the spectral detection surface 40, realizing point convergence and improving spectral resolution.

[0057] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0058] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0059] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for spectral separation of extreme ultraviolet and X-rays, characterized in that, Includes the following steps: Step S1: Obtain the incident beam (10), which contains at least the extreme ultraviolet and X-ray spectra; Step S2: Obtain the focusing lens (20) of the spectrometer, so that the incident beam (10) enters the focusing lens (20) at a grazing incident angle, and the focusing lens (20) converges the incident beam (10); Step S3: Obtain the conical diffraction grating (30) of the spectrometer. The conical diffraction grating (30) is used to receive the converging light output by the focusing lens (20) and perform diffraction to separate the incident beam (10) of different wavelengths. Step S4: Adjust the relative position between the focusing lens (20) and the conical diffraction grating (30) so that the aberrations generated between the focusing lens (20) and the conical diffraction grating (30) cancel each other out, and at the same time make the conical diffraction grating (30) output a focused beam; Step S4 further includes: Step S41: Determine the zero-order reflection position of the conical diffraction grating (30); Step S42: Adjust the rotation angle of the focusing lens (20) so that the converging light output by the focusing lens (20) undergoes zero-order reflection on the conical diffraction grating (30) and the focused beam output by the conical diffraction grating (30) is focused on the spectral detection surface (40) of the spectrometer. In step S42, the rotation angle of the focusing lens (20) is adjusted so that the diffraction order m of the conical diffraction grating (30), the wavelength λ of the incident beam (10), the grating line spacing d of the conical diffraction grating (30), the angle γ2 of the beam incident on the conical diffraction grating (30), the elevation angle α of the beam incident on the conical diffraction grating (30), and the elevation angle β of the focused beam output by the conical diffraction grating (30) satisfy the following: mλ / d=sinγ2(sinα+sinβ).

2. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S2, the focusing lens (20) converges the incident beam (10) and outputs it in the form of reflection; In step S4, the conical diffraction grating (30) separates and outputs the incident beams (10) of different wavelengths in the form of reflection.

3. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S42, the focusing lens (20) has a rotation center axis (21) that is parallel to the conical diffraction grating (30).

4. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S2, the focusing lens (20) is a tire mirror (22).

5. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S2, the focusing lens (20) is an ellipsoidal lens.

6. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S2, the incident beam (10) enters the focusing lens (20) at a first grazing incident angle. In step S3, the converging light output by the focusing lens (20) enters the conical diffraction grating (30) at a second grazing incident angle. The first grazing angle of incidence is equal to the second grazing angle of incidence; or The first grazing angle of incidence is not equal to the second grazing angle of incidence.

7. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S3, The density of the conical diffraction grating (30) is set to be greater than or equal to 200 lines / mm and less than 500 lines / mm; or The density of the conical diffraction grating (30) is set to be greater than or equal to 500 lines / mm and less than or equal to 5000 lines / mm.

8. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S1, the wavelength range of the incident beam (10) satisfies greater than or equal to 0.1 nm and less than or equal to 200 nm.

9. The spectral separation method for extreme ultraviolet and X-rays according to claim 1, characterized in that, In step S42, the diameter of the focused beam received on the spectral detection surface (40) is in the range of greater than or equal to 1 micrometer and less than or equal to 1000 micrometers.

10. A spectrometer, characterized in that, The spectrometer is any one of claims 1 to 9. The spectrometer includes at least a light source, a focusing lens (20), and a conical diffraction grating (30) along the optical path transmission direction. The light source is capable of emitting at least extreme ultraviolet light beams and X-ray beams. The focusing lens (20) is used to receive the light beam emitted by the light source, focus the light beam, and reflect it to the conical diffraction grating (30). The conical diffraction grating (30) is used to receive the light beam from the focusing lens (20) and perform diffraction to separate the light beams of different wavelengths and project them onto the spectral detection surface (40) of the spectrometer.

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