Sample disc and spectrometer for near-infrared diffuse reflection spectrum acquisition

Abstract

The utility model relates to the field of near-infrared analytical instruments, and discloses a paraboloid-shaped sample disc and a spectrograph for near-infrared diffuse reflection spectrum acquisition, the paraboloid-shaped sample disc comprises a sample box for storing samples, the sample box is provided with a first side and a second side which are opposite, the first side of the sample box is transparent, the second side of the sample box is provided with a paraboloid-shaped reflector, and the paraboloid-shaped reflector is arranged on the first side of the sample box; the paraboloid of the paraboloid type reflecting mirror faces the first side of the sample box, and the spectrograph corresponds to the sample box. According to the device, scattered light and transmission light which are not received by the optical fiber originally are utilized through the paraboloid type reflecting mirror and the quartz glass, the absorbance value of a solid sample is increased, the scattering effect is reduced, and the background noise intensity is reduced; wavelength calibration is achieved through the PET sheet and the ceramic white board, and errors caused by light source intensity fluctuation and wavelength drift in the detection process are reduced. Finally, the baseline drift phenomenon and the stray light problem in an optical path system are reduced, the sampling representativeness is improved, the result repeatability and the signal-to-noise ratio are improved, and the spectrum collection accuracy is remarkably improved.

Description

Technical Field

[0001] This application relates to the technical field of near-infrared analysis instruments, and specifically to a sample disk and a spectrometer for near-infrared diffuse reflection spectrum acquisition. Background Art

[0002] In the current near-infrared diffuse reflection sampling process, there is strong scattering and transmission, and the baseline signal has a non-linear response, introducing errors in near-infrared analysis. Therefore, in order to improve the accuracy of near-infrared analysis, it is necessary to study the sample disk. Summary of the Utility Model

[0003] The purpose of this application is to provide a parabolic sample disk and a spectrometer for near-infrared diffuse reflection spectrum acquisition, so as to solve the technical problems raised in the above background art.

[0004] To achieve the above purpose, this application discloses the following technical solutions:

[0005] This application discloses a sample disk for near-infrared diffuse reflection spectrum acquisition in the first aspect. The sample disk includes: a sample box for storing samples. The sample box has opposite first and second sides. The first side of the sample box is transparent, and a parabolic mirror is provided on the second side of the sample box. The parabolic surface of the parabolic mirror faces the first side of the sample box.

[0006] Preferably, the transparent part of the first side of the sample box is quartz glass, sapphire glass or ground glass.

[0007] Preferably, it further includes a housing, and the sample box is detachably arranged on the housing.

[0008] Preferably, the housing has opposite first and second sides of the housing and a side wall of the housing. The first side and the second side of the housing are arranged opposite to each other, and the side wall of the housing is arranged between the first side and the second side of the housing.

[0009] Preferably, a plurality of openings are provided on the first side of the housing, and PET sheets and ceramic white boards are respectively installed on the openings in one-to-one correspondence.

[0010] This application discloses a spectrometer for near-infrared diffuse reflection spectrum acquisition in the second aspect. The spectrometer includes:

[0011] The sample disk for near-infrared diffuse reflection spectrum acquisition as described above;

[0012] A light source;

[0013] A spectrometer;

[0014] An optical fiber having an input end and an output end, wherein the end face of the input end of the optical fiber coincides with the focus of a parabolic mirror, and the output end of the optical fiber is connected to the spectrometer.

[0015] Advantageous effects: The sample disk and spectrometer for near-infrared diffuse reflection spectroscopy of the present application utilize a parabolic mirror and quartz glass to reutilize the scattered light and transmitted light that were not originally received by the optical fiber, thereby enhancing the absorbance value of solid samples, reducing the scattering effect, and lowering the background noise intensity. The PET sheet and ceramic whiteboard are used to calibrate the wavelength, reducing the errors introduced by fluctuations in the light source intensity and wavelength drift during the detection process. Finally, it effectively reduces the baseline drift phenomenon, increases the sampling representativeness, improves the result repeatability, reduces the stray light problem in the optical path system, and enhances the signal-to-noise ratio, significantly improving the accuracy of spectral acquisition. Description of the Drawings

[0016] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0017] Figure 1 Isometric view of the sample disk for near-infrared diffuse reflection spectroscopy provided by the embodiment of the present application;

[0018] Figure 2 Front view of the sample disk for near-infrared diffuse reflection spectroscopy provided by the embodiment of the present application;

[0019] Figure 3 Schematic optical path diagram with a parabolic mirror provided by the embodiment of the present application;

[0020] Figure 4 Schematic optical path diagram without a parabolic mirror provided by the prior art;

[0021] Figure 5 Schematic diagram of absorbance comparison with and without a parabolic mirror for the same standard sample provided by the embodiment of the present application;

[0022] In the figures: 1, parabolic mirror; 2, quartz glass; 3, housing; 4, PET sheet; 5, ceramic whiteboard; 6, with parabolic mirror; 7, light source; 8, optical fiber; 9, without parabolic mirror. Detailed Embodiments

[0023] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0024] In this article, the term "including" is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, the elements defined by the statement "including..." do not exclude the presence of additional identical elements in the process, method, article or device including the said elements.

[0025] In the first aspect, as shown in Figure 1 and Figure 2 , an embodiment discloses a sample disk for near-infrared diffuse reflection spectrum collection. The sample disk includes: a sample box for storing samples. The sample box has opposite first and second sides. The first side of the sample box is transparent, and a parabolic mirror 1 is provided on the second side of the sample box. The parabolic surface of the parabolic mirror 1 faces the first side of the sample box.

[0026] Specifically, the transparent part of the first side of the sample box is quartz glass 2, or it can also be sapphire glass or ground glass.

[0027] Specifically, it further includes a housing 3, and the sample box is detachably arranged on the housing 3.

[0028] Specifically, the housing 3 has opposite first and second sides of the housing and a housing side wall. The first and second sides of the housing are arranged opposite to each other, and the housing side wall is arranged between the first and second sides of the housing.

[0029] Specifically, a plurality of openings are provided on the first side of the housing, and PET sheets 4 and ceramic whiteboards 5 are respectively installed on the openings in one-to-one correspondence.

[0030] In the second aspect, an embodiment of the present application discloses a spectrometer for near-infrared diffuse reflection spectrum collection. The spectrometer includes:

[0031] The sample disk for near-infrared diffuse reflection spectrum collection as described above;

[0032] A light source;

[0033] A spectrometer;

[0034] An optical fiber. The optical fiber has an input end and an output end. The end face of the input end of the optical fiber coincides with the focus of the parabolic mirror, and the output end of the optical fiber is connected to the spectrometer.

[0035] In a simple example, the input and output of the optical signal during detection are as Figure 3 shown. The thick arrow represents the optical path. A part of the light emitted by the light source passes through the quartz glass and generates diffuse reflection on the surface of the solid sample, and the other part transmits through the solid sample and is reflected by the parabolic mirror towards the optical fiber. After passing through the solid sample for secondary transmission, it is finally received by the optical fiber. On the contrary, the input and output of the optical signal during detection in the prior art are as Figure 4 shown. In the case without a parabolic mirror, the optical fiber only receives the light diffusely reflected from the surface of the solid sample, and the rest of the light transmits into the ordinary sample tray or scatters and dissipates in the gaps of the solid sample.

[0036] In this embodiment, the focus of the parabolic mirror is the receiving section of the optical fiber, and the focus of the parabolic mirror is calculated from the three-dimensional equation of the parabolic mirror;

[0037] The three-dimensional equation of the parabolic mirror is:

[0038]

[0039] where c is the value in the actual optical fiber position coordinates (0, 0, c), is the mathematical equation of the concave surface of the paraboloid, a > 0, b > 0, and the focus of the parabolic mirror is given by the solution (x, y, z) of the three-dimensional equation of the parabolic mirror.

[0040] Designing the parabolic mirror based on the actual optical fiber position coordinates optimizes the optical reflection path and improves the quality of near-infrared diffuse reflection spectrum collection.

[0041] In a simple comparative example, combined with Figure 5 , for the same standard sample, the acquisition parameters are set as wavelength 900 nm - 1700 nm, and the acquisition average number is set as 10 times. It can be seen from the measured comparison data that for the key wavelengths of the sample at 950 nm - 1050 nm and 1100 nm - 1300 nm, the absorbance is significantly improved in the case of having a parabolic mirror.

[0042] In summary, the sample tray and spectrometer for near-infrared diffuse reflection spectrum collection in this embodiment realize the secondary utilization of the scattered light and transmitted light that were not originally received by the optical fiber through the parabolic mirror and quartz glass, improve the absorbance value of the solid sample, reduce the scattering effect, and reduce the background noise intensity; wavelength calibration is achieved through the PET sheet and the ceramic whiteboard to reduce the errors introduced by the fluctuation of the light source intensity and wavelength drift during the detection process. Finally, the baseline drift phenomenon is effectively reduced, the sampling representativeness is increased, the result repeatability is improved, the stray light problem in the optical path system is reduced, the signal-to-noise ratio is increased, and the accuracy of spectrum collection is significantly improved.

[0043] Finally, it should be noted that the above are only the preferred embodiments of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A sample plate for collecting near-infrared diffuse reflectance spectra, characterized in that: The sample tray comprises: a sample box for storing samples, wherein the sample box has a first side and a second side opposite to each other, the first side of the sample box is transparent, and a parabolic reflector is arranged on the second side of the sample box, wherein the parabola of the parabolic reflector faces the first side of the sample box.

2. The sample tray for near-infrared diffuse reflectance spectrum collection according to claim 1, characterized in that: The transparent portion of the first side of the sample box is made of quartz glass, sapphire glass or frosted glass.

3. The sample tray for near-infrared diffuse reflectance spectrum collection according to claim 1, characterized in that: The invention also comprises a housing, on which the sample box is detachably arranged.

4. The sample tray for collecting near-infrared diffuse reflectance spectra according to claim 3, characterized in that: The shell has a first shell side, a second shell side and a shell side wall which are opposite to each other. The first shell side and the second shell side are arranged opposite to each other, and the shell side wall is arranged between the first shell side and the second shell side.

5. The sample tray for collecting near-infrared diffuse reflectance spectra according to claim 4, characterized in that: A plurality of openings are arranged on the first side of the shell, and PET sheets and ceramic whiteboards are mounted on the openings in a one-to-one correspondence.

6. A spectrometer for collecting near-infrared diffuse reflectance spectra, characterized in that: The spectrometer includes: A sample tray for collecting near-infrared diffuse reflectance spectra as described in any one of claims 1 to 5; light source; Spectrometer; The optical fiber has an input end and an output end, the input end face of the optical fiber coincides with the focus of the parabolic reflector, and the output end of the optical fiber is connected to the spectrometer.

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