An extreme ultraviolet spectral line detection instrument

Abstract

This invention discloses an extreme ultraviolet (EUV) spectral line detection instrument, comprising a beam collimator, a filter assembly, a slit component, a grating, and a detector. The filter assembly includes a filter wheel and a filter. The slit component forms a working slit and a calibration slit. The horizontal distance between the working slit and the grating is smaller than the horizontal distance between the detector and the grating, causing the positional relationship between the working slit, the grating, and the detector to deviate from the traditional Rowland circle relationship. When the EUV spectral line detection instrument is working normally, the working optical path is open and the calibration optical path is closed. When the EUV spectral line detection instrument calibrates the working slit light, both the working and calibration optical paths are open. The incident light, collimated by the beam collimator, is filtered by the filter and then enters the first position of the grating through the working slit, converging to the first position of the detector. The incident light, collimated by the beam collimator, is filtered by the filter and then enters the second position of the grating through the calibration slit, converging to the second position of the detector.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of extreme ultraviolet spectral line detection, and particularly relates to a high-sensitivity extreme ultraviolet spectral line detection instrument with on-orbit self-calibration function for space application. BACKGROUND

[0002] There are a large number of celestial objects in the universe, such as stars, active galactic nuclei, supernovae, neutron stars, black holes and interstellar matter, which can radiate a large number of extreme ultraviolet photon radiations. By observing the spectral lines of these astronomical targets in the extreme ultraviolet band, a large number of major scientific problems can be explored, such as the physical phenomena and material composition around the celestial objects, the study of the morphological evolution law of the celestial objects, the analysis of the interstellar matter composition and the study of the origin and evolution of black holes. However, the existing extreme ultraviolet spectral line measurement instruments have problems such as insufficient sensitivity and on-orbit performance degradation, which result in that the weak space astronomical targets cannot be detected with high-precision quantitative spectral lines. SUMMARY

[0003] The present application relates to the field of extreme ultraviolet spectral line detection, and particularly relates to a high-sensitivity extreme ultraviolet spectral line detection instrument with on-orbit self-calibration function for space application.

[0004] To achieve the above-mentioned purpose, the present application provides the following scheme:

[0005] An extreme ultraviolet spectral line detection instrument, comprising a light beam collimator, a filter assembly, a slit component, a grating and a detector, the filter assembly comprising a rotatable filter wheel and at least two filters arranged on the filter wheel, the slit component being formed with a working slit and a calibration slit arranged side by side, the light beam collimator, the filter assembly, the working slit, the grating and the detector forming a working light path, and the light beam collimator, the filter assembly, the calibration slit, the grating and the detector forming a calibration light path, a horizontal distance between the working slit and the grating being less than a horizontal distance between the detector and the grating so that a positional relationship among the working slit, the grating and the detector deviates from a conventional Rowland circle relationship; when the extreme ultraviolet spectral line detection instrument is used for normal operation, the working light path is open, the calibration light path is closed, and an incident light ray collimated by the light beam collimator is incident on the grating at a first position via the working slit and is converged on the detector at a first position; when the extreme ultraviolet spectral line detection instrument is used for calibration of the working slit light, the working light path is open, the calibration light path is open, an incident light ray collimated by the light beam collimator is filtered by the filters, is incident on the grating at the first position via the working slit and is converged on the detector at the first position, and an incident light ray collimated by the light beam collimator is filtered by the filters, is incident on the grating at a second position via the calibration slit and is converged on the detector at a second position.

[0006] Preferably, the working slit has a width of 0.01-0.03 mm and a length of 1-3 mm, the calibration slit has a width of 0.01-0.03 mm and a length of 1-3 mm, a distance between the working slit and the calibration slit is 5-15 mm, a distance between the working slit and the grating and a distance between the calibration slit and the grating are both 45-80 mm, a distance between the detector and the grating is 230-265 mm, and an angle between the incident light ray and a normal line of the detector is 5-15°.

[0007] Preferably, the working slit has a width of 0.02 mm and a length of 2 mm, the calibration slit has a width of 0.02 mm and a length of 2 mm, a distance between the working slit and the calibration slit is 10 mm, a distance between the working slit and the grating and a distance between the calibration slit and the grating are both 65 mm, a distance between the detector and the grating is 245 mm, and an angle between the incident light ray and a normal line of the detector is 10°.

[0008] Preferably, the grating is a grazing incidence concave grating, the grating has a line density of 2600 L / mm, an effective area of 25 mm*25 mm and a light ray grazing incidence angle of 80°.

[0009] Preferably, the grating surface is plated with a metal film.

[0010] Preferably, the detector is a high-sensitivity single-photon area array detector based on an MCP position-sensitive anode, and the detector surface is plated with a KBr cathode.

[0011] Preferably, the filter wheel is provided with at least two metal film filters with the same parameters.

[0012] Preferably, the extreme ultraviolet spectral line detection instrument further comprises a housing, and the beam collimator, the filter assembly, the slit component, the grating and the detector are integrated on the housing along an optical path.

[0013] The extreme ultraviolet spectral line detection instrument provided by the present application has the following advantages:

[0014] First, the horizontal distance between the working slit and the grating is less than the horizontal distance between the detector and the grating, the working slit deviates from the curvature circumference of the grating, so that more optimization variables can be obtained, system aberration can be reduced, and the included angle between the outgoing light and the detector can be reduced, so that the detection efficiency can be improved.

[0015] Second, the extreme ultraviolet spectral line detection instrument is provided with a working slit and a calibration slit at the same time, when the extreme ultraviolet spectral line detection instrument is normally working, the working light path is opened to detect the target spectrum through the rotation of the filter wheel; when calibration is performed, the calibration light path is simultaneously enabled, the radiation response attenuation of the working light path is calibrated by comparing the same target spectrum signal of the calibration light path and the working light path, the on-orbit calibration of the working slit light is realized, and high-precision quantitative remote sensing of on-orbit data of the instrument is ensured.

[0016] Third, the working light path and the calibration light path are separated, the working light path is opened to detect the target spectrum, and the calibration light path is in a closed state, so that the grating and the detector area of the calibration light path are not irradiated by light, and performance attenuation can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor based on the drawings shown.

[0018] Figure 1 is a structural schematic diagram of the extreme ultraviolet spectral line detection instrument provided by the embodiment of the present application;

[0019] Figure 2is a top view of an extreme ultraviolet spectral line detection instrument provided by an embodiment of the present application;

[0020] Figure 3 is a structural schematic diagram of a grating provided by an embodiment of the present application;

[0021] Figure 4 is a partial optical path schematic diagram of simultaneous opening of a working optical path and a calibration optical path provided by an embodiment of the present application;

[0022] Figure 5 is a spectral resolution situation schematic diagram of an extreme ultraviolet spectral line detection instrument at 5nm-10nm in a simulation test provided by an embodiment of the present application;

[0023] Figure 6 is a spectral resolution situation schematic diagram of an extreme ultraviolet spectral line detection instrument at 15nm-20nm in a simulation test provided by an embodiment of the present application;

[0024] Figure 7 is a spectral resolution situation schematic diagram of an extreme ultraviolet spectral line detection instrument at 30nm-35nm in a simulation test provided by an embodiment of the present application.

[0025] BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 10, beam collimator; 20, light filtering assembly; 21, light filter wheel; 22, light filter; 30, slit component; 31, working slit; 32, calibration slit; 40, grating; 41, grating seat; 50, detector; 60, shell. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0028] It should be noted that all directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directionality indications also change accordingly.

[0029] It should also be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or can have a middle element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or can have a middle element.

[0030] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0031] like Figures 1 to 4 As shown, this is an extreme ultraviolet (EUV) spectral line detector according to an embodiment of the present invention. The slit, grating, and detector no longer follow the Rowland circle design structure, that is, the slit and detector 50 are not on the curvature circumference of the grating 49. After overcoming this limitation, by setting optimization functions through optical design software, optimization design is carried out on key parameters such as grating lines, grating curvature radius, distance between slit and grating 40, distance between detector 50 and grating 40, and incident angle of detector 50. Finally, an optimized optomechanical system design structure is obtained. Therefore, this EUV spectral line detector has high sensitivity for EUV spectral line detection and also has the ability to self-calibrate on-orbit radiation response.

[0032] Please see Figures 1-4 The extreme ultraviolet spectral line detection instrument of this invention includes a beam collimator 10, a filter assembly 20, a slit component 30, a grating 40, and a detector 50. The filter assembly 20 includes a rotatable filter wheel 21 and at least two filters 22 disposed on the filter wheel 21. The slit component 30 forms a working slit 31 and a calibration slit 32 arranged side by side. The horizontal distance between the working slit 31 and the grating 40 (e.g., ...) is... Figure 2As shown, the horizontal distance between the working slit 31 and the grating 40 refers to the distance in the X direction) is less than the horizontal distance between the detector 50 and the grating 40, so that the positional relationship among the working slit 31, the grating 40 and the detector 50 deviates from the traditional Rowland circle relationship, and the beam collimator 10, the light filtering assembly 20, the working slit 31, the grating 40 and the detector 50 form a working light path, and the beam collimator 10, the light filtering assembly 20, the calibration slit 32, the grating 40 and the detector 50 form a calibration light path; when the extreme ultraviolet spectral line detection instrument is used for normal work, the working light path is opened, and the calibration light path is closed, the incident light rays collimated by the beam collimator 10 are incident on the first position of the grating 40 through the working slit 31, and are converged on the first position of the detector 50; when the extreme ultraviolet spectral line detection instrument is used for on-orbit calibration of the working slit 31 light, the working light path is opened, and the calibration light path is opened, the incident light rays collimated by the beam collimator 10 are filtered by the filter 22, then are incident on the first position of the grating 40 through the working slit 31, and are converged on the first position of the detector 50, and the incident light rays collimated by the beam collimator 10 are filtered by the filter 22, then are incident on the second position of the grating 40 through the calibration slit 32, and are converged on the second position of the detector 50.

[0033] As shown, the first position of the grating 40 and the second position of the grating 40 are two positions of the grating 40, and the two positions are different. Figure 4 As shown, the first position of the grating 40 and the second position of the grating 40 are two positions of the grating 40, and the two positions are different.

[0034] The working mode of the extreme ultraviolet spectral line detection instrument is as follows: the extreme ultraviolet space astronomical target light rays are irradiated on the light filtering assembly 20 after passing through the beam collimator 10, and the out-of-band stray light from far ultraviolet to infrared is filtered out by the light filtering assembly 20; the filter wheel 21 selects the working slit 31 or the calibration slit 32; the light rays enter the inside of the detection instrument through the filter 22 and the slit, and are incident on the grating 40 at a grazing incidence angle; the grating 40 converges the light rays on the detector 50 after performing light splitting on the incident light rays; the detector 50 collects the spectral line images of different wavelengths of the incident photons in the form of single-photon imaging, and obtains the extreme ultraviolet spectral line distribution of the space astronomical target.

[0035] In addition, when the extreme ultraviolet spectral line detection instrument is normally working, the working light path is opened to detect the target spectrum by rotating the filter wheel 21, and the calibration light path is in a closed state; when calibration is performed, the calibration slit 32 is enabled, and the radiation response attenuation of the working light path is calibrated by comparing the same target spectral signal of the calibration light path and the working light path.

[0036] The extreme ultraviolet spectral line detection instrument has the following advantages:

[0037] First, the horizontal distance between the working slit 31 and the grating 40 is less than the horizontal distance between the detector 50 and the grating 40, the working slit 31 is deviated from the curvature circumference of the grating 40 with the detector 50, so that more optimization variables can be obtained, the system aberration can be reduced, and the included angle between the outgoing light and the detector 50 can be reduced, so that the detection efficiency can be improved.

[0038] Second, the extreme ultraviolet spectral line detection instrument is provided with the working slit 31 and the calibration slit 32, when the extreme ultraviolet spectral line detection instrument works normally, the working light path is opened to detect the target spectrum through the rotation of the filter wheel 21; when calibration is performed, the calibration light path is simultaneously started, the same target spectrum signal is detected through the comparison between the calibration light path and the working light path, the radiation response attenuation of the working light path is calibrated, the on-orbit calibration of the working slit 31 light is realized, and high-precision quantitative remote sensing of on-orbit data of the instrument is ensured.

[0039] Third, the working light path and the calibration light path are separated, the working light path is opened to detect the target spectrum, and the calibration light path is in a closed state, so that the grating 40 and the detector 50 region of the calibration light path are not irradiated by light, and performance attenuation can be avoided.

[0040] Understandably, the beam collimator 10 is used to limit the angle range of the incident light, and the angle range of the incident light can be limited by controlling the size and overall length of the light inlet of the beam collimator 10.

[0041] Preferably, the width of the working slit 31 is 0.01 mm-0.03 mm, the length is 1 mm-3 mm, the width of the calibration slit 32 is 0.01-0.03 mm, the length is 1 mm-3 mm, the distance between the working slit 31 and the calibration slit 32 is 5 mm-15 mm, the distance between the working slit 31 and the grating 40 and the distance between the calibration slit 32 and the grating 40 are both 45 mm-80 mm, the distance between the detector 50 and the grating 40 is 230 mm-265 mm, and the included angle between the incident light and the normal line of the detector 50 is 5°-15°.

[0042] Exemplarily, the width of the working slit 31 is 0.02 mm, the length is 2 mm, the width of the calibration slit 32 is 0.02 mm, the length is 2 mm, the distance between the working slit 31 and the calibration slit 32 is 10 mm, the distance between the working slit 31 and the grating 40 and the distance between the calibration slit 32 and the grating 40 are both 65 mm, the distance between the detector 50 and the grating 40 is 245 mm, and the included angle between the incident light and the normal line of the detector 50 is 10°. When the extreme ultraviolet spectral line detection instrument is used for detection, the highest spectral resolution can be obtained in the extreme ultraviolet band, and the spectral resolution is better than 0.3 nm in the range of 5 nm-30 nm.

[0043] Preferably, the grating 40 is a blazed concave grating, the grating 40 has a ruling density of 2600 L / mm, an effective area of 25mm*25mm, and a light grazing incidence angle of 80°.

[0044] Further, the grating 40 is coated with a metal film, such as a gold film or a silver film.

[0045] Preferably, the detector 50 is a high-sensitivity single-photon area array detector based on MCP, and the detector 50 is coated with a KBr cathode, so as to improve the detection sensitivity of the extreme ultraviolet spectral line detection instrument to weak extreme ultraviolet spectral lines and maximize the signal-to-noise ratio of spectral line detection.

[0046] The at least two filters 22 are the same in parameters and are metal film filters, which can filter out far ultraviolet to infrared non-working band stray light. That is, the filter wheel 21 is provided with at least two metal film filters which are the same in parameters.

[0047] Preferably, the extreme ultraviolet spectral line detection instrument further comprises a shell 60, and the beam collimator 10, the filter assembly 20, the slit component 30, the grating 40 and the detector 50 are integrated on the shell 60 along an optical path, so as to improve the integration of the extreme ultraviolet spectral line detection instrument and facilitate installation and placement.

[0048] Optionally, the grating 40 is installed on the shell 60 through a grating seat 41.

[0049] The spectral resolution performance of the extreme ultraviolet spectral line detection instrument of the embodiment of the application is analyzed by using an extreme ultraviolet spectral instrument design software. As shown in the simulation test, the spectral resolution of the extreme ultraviolet spectral line detection instrument of the embodiment of the application at 5nm-10nm, 15nm-20nm and 30nm-35nm is as shown in the following table. Figures 5-6 As can be seen from the table, the spectral lines of different wavelength regions with a wavelength interval of 0.3nm can be clearly distinguished, that is, the spectral resolution of the system is better than 0.3nm.

[0050] The above description is only preferred embodiments of the application, and does not limit the patent scope of the application. Any equivalent structural transformation made according to the content of the specification and drawings, or direct / indirect application in other related technical fields under the inventive concept of the application is included in the patent protection scope of the application.

Claims

1. An extreme ultraviolet spectral line detection instrument, characterized in that, The system includes a beam collimator, a filter assembly, a slit component, a grating, and a detector. The filter assembly includes a rotatable filter wheel and at least two filters disposed on the filter wheel. The slit component forms a working slit and a calibration slit arranged side by side. The beam collimator, the filter assembly, the working slit, the grating, and the detector form a working optical path, and the beam collimator, the filter assembly, the calibration slit, the grating, and the detector form a calibration optical path. The horizontal distance between the working slit and the grating is smaller than the horizontal distance between the detector and the grating, so that the positional relationship between the working slit, the grating, and the detector deviates from the traditional Rowland circle relationship. The extreme ultraviolet (EUV) When the spectral line detection instrument is in normal operation, the working optical path is open and the calibration optical path is closed. The incident light, after being collimated by the beam collimator, enters the first position of the grating through the working slit and is then converged to the first position of the detector. When the extreme ultraviolet spectral line detection instrument is used for calibration of the working slit light, the working optical path is open and the calibration optical path is open. The incident light, after being collimated by the beam collimator, is filtered by the filter and enters the first position of the grating through the working slit, and is then converged to the first position of the detector. The incident light, after being collimated by the beam collimator, is filtered by the filter and enters the second position of the grating through the calibration slit, and is then converged to the second position of the detector.

2. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, The working slit has a width of 0.01mm-0.03mm and a length of 1mm-3mm. The calibration slit has a width of 0.01mm-0.03mm and a length of 1-3mm. The distance between the working slit and the calibration slit is 5mm-15mm. The distance between the working slit and the grating and the distance between the calibration slit and the grating are both 45mm-80mm. The distance between the detector and the grating is 230mm-265mm. The angle between the incident light and the normal to the detector is 5°-15°.

3. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, The working slit has a width of 0.02 mm and a length of 2 mm. The calibration slit has a width of 0.02 mm and a length of 2 mm. The distance between the working slit and the calibration slit is 10 mm. The distance between the working slit and the grating and the distance between the calibration slit and the grating are both 65 mm. The distance between the detector and the grating is 245 mm. The angle between the incident light ray and the normal of the detector is 10°.

4. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, The grating is a grazing incidence concave grating with a grating line density of 2600 L / mm, an effective area of ​​25mm*25mm, and a grazing incidence angle of 80°.

5. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, The grating surface is coated with a metal film.

6. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, The detector is a high-sensitivity single-photon array detector based on MCP position-sensitive anode, and the detector surface is coated with KBr cathode.

7. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, At least two metal thin-film filters with identical parameters are installed on the filter wheel.

8. The extreme ultraviolet spectral line detection instrument as described in claim 1, characterized in that, The extreme ultraviolet spectral line detector also includes a housing, on which the beam collimator, the filter assembly, the slit component, the grating, and the detector are integrated along the optical path.

Images