A symmetrical, flat-field, non-glued Raman spectrometer optical system

Abstract

The present application provides a symmetrical, flat-field, glue-free Raman spectrometer optical system, comprising: a collimating lens group consisting of a first number of coaxially arranged lenses, and an imaging lens group consisting of a second number of coaxially arranged lenses, arranged sequentially from the object side to the image side; the first number of coaxially arranged lenses and the second number of coaxially arranged lenses each include at least one lens with both convex surfaces and at least one lens with both concave surfaces; the lenses in the collimating lens group and the lenses in the imaging lens group are coaxially arranged. In this solution, the focal points of different Raman wavelengths remain planar when the image plane is expanded, perpendicular to the optical axis, and closely align with the planar imaging target surface of current detectors. This reduces processing costs and assembly difficulty, and the structure does not contain glue for gluing the lenses together, thus avoiding the introduction of additional Raman signals spontaneously generated by the glue.

Description

Technical Field

[0001] The present invention relates to the technical field of Raman spectroscopy systems, and in particular to a Raman spectrometer optical system. Background Art

[0002] Raman spectroscopy is a scattering spectrum of molecular chemical bond vibrations, which can be used to obtain information about molecular structure through spectral analysis. It requires no sample preparation and can be measured directly on any gaseous, liquid, or solid sample using a fiber optic probe or through glass, quartz, or optical fibers. It provides fast, simple, repeatable, and, more importantly, non-destructive qualitative and quantitative analysis, making it a key tool for structural analysis of organic compounds. In recent years, numerous studies have demonstrated that Raman spectroscopy can effectively identify the biochemical components of biological substances, thereby obtaining their "whole-organism fingerprints." Therefore, Raman spectroscopy is also an effective analytical tool for rapidly identifying the molecular components within cells of biological substances. The rapid and efficient use of Raman spectroscopy to identify biological substances has attracted widespread attention among researchers.

[0003] Currently, the fingerprint spectra of biological substances are mostly concentrated at 400 cm -1 ~3500cm -1 , and the most prominent carbon-hydrogen (CH) peak in biological matter is located at 2970 cm -1 Therefore, for an excitation wavelength of 532 nm, the corresponding wavelength of the excited Raman signal is 540 nm to 650 nm.

[0004] Raman spectrometers in the prior art mostly use multiple mirrors, including mirrors for beam collimation and mirrors for beam focusing, which use off-axis spherical reflectors, off-axis parabolic reflectors, off-axis hyperbolic reflectors, free-form reflectors, and other forms. Among them, the off-axis spherical reflectors, off-axis parabolic reflectors, and off-axis hyperbolic reflectors are optical systems. However, the optical systems in the prior art solutions have different Raman wavelength focusing points, which appear curved when the image plane is expanded, that is, the image plane is not flat, which is contrary to the current technical status quo that the detector imaging target surface is flat. Another solution in the prior art solution requires the addition of a suitable compensating mirror to achieve the purpose of image flatness. The compensating mirror corrects multiple aberrations such as coma, field curvature, and astigmatism. The surface design is relatively complex, resulting in the inability to meet the requirements of existing conventional processing levels, resulting in a significant increase in processing and assembly costs. In addition, although the use of free-form reflectors can reduce the placement of compensating mirrors, it involves the processing and assembly of free-form surfaces, and the difficulty coefficient and research and development cost of assembling multiple off-axis free-form mirrors are also very high.

[0005] Therefore, the optical system in the existing technical solution has a technical problem in which the focusing points of different Raman wavelengths appear curved when the image plane is expanded, that is, the image plane is not flat. At the same time, the assembly difficulty coefficient and research and development cost of the multiple off-axis free-form surface mirrors involved are very high. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the technical problem in the optical system of the prior art that the focal points of different Raman wavelengths present a curved surface state when the image plane is expanded, that is, the image plane is not flat. At the same time, the technical defects of the high difficulty coefficient and development cost of assembling multiple off-axis free-form surface mirrors involved are overcome, thereby providing a symmetrical, flat-image-field, and non-glued Raman spectrometer optical system.

[0007] According to an embodiment of the present application, a symmetrical, flat-field, glue-free Raman spectrometer optical system is provided, comprising:

[0008] A collimating lens group consisting of a first number of lenses arranged on the same optical axis, and an imaging lens group consisting of a second number of lenses arranged on the same optical axis, arranged sequentially from the object side to the image side;

[0009] The first number of lenses arranged on the same optical axis and the second number of lenses arranged on the same optical axis each include at least one lens with both sides being convex and at least one lens with both sides being concave;

[0010] The lenses in the collimating lens group and the lenses in the imaging lens group are arranged on the same optical axis.

[0011] Preferably, the first quantity and the second quantity are both 6;

[0012] The lenses constituting the collimating lens group are a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens;

[0013] The lenses constituting the imaging lens group are the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens and the twelfth lens.

[0014] Preferably, both mirror surfaces of the first lens are convex surfaces;

[0015] Both mirror surfaces of the second lens are convex;

[0016] Both mirror surfaces of the third lens are concave;

[0017] Both mirror surfaces of the fourth lens are concave;

[0018] Both mirror surfaces of the fifth lens are convex;

[0019] One mirror surface of the sixth lens is convex, and the other mirror surface is concave. The sixth lens has a concave surface facing the object side and a convex surface facing the image side.

[0020] Preferably, the first lens includes a first mirror surface and a second mirror surface; the first mirror surface is the mirror surface of the first lens facing the object side, and the second mirror surface is the mirror surface of the first lens facing the image side;

[0021] The second lens includes a third mirror surface and a fourth mirror surface; the third mirror surface is the mirror surface of the second lens facing the object side, and the fourth mirror surface is the mirror surface of the second lens facing the image side;

[0022] The third lens includes a fifth mirror surface and a sixth mirror surface; the fifth mirror surface is the mirror surface of the third lens facing the object side, and the sixth mirror surface is the mirror surface of the third lens facing the image side;

[0023] The fourth lens includes a seventh mirror surface and an eighth mirror surface; the seventh mirror surface is the mirror surface of the fourth lens facing the object side, and the eighth mirror surface is the mirror surface of the fourth lens facing the image side;

[0024] The fifth lens includes a ninth mirror surface and a tenth mirror surface; the ninth mirror surface is the mirror surface of the fifth lens facing the object side, and the tenth mirror surface is the mirror surface of the fifth lens facing the image side;

[0025] The sixth lens includes an eleventh mirror surface and a twelfth mirror surface; the eleventh mirror surface is the mirror surface of the sixth lens facing the object side, and the twelfth mirror surface is the mirror surface of the sixth lens facing the image side;

[0026] The curvature radius of the first mirror is 733.29 to 742.50 mm, the mirror spacing of the first mirror is 13.10 to 15.90 mm, and the effective clear aperture of the first mirror is 20.54 to 21.65 mm; the curvature radius of the second mirror is -327.40 to -323.20 mm, the mirror spacing of the second mirror is 90.74 to 95.34 mm, and the effective clear aperture of the second mirror is 20.66 to 22.43 mm;

[0027] The curvature radius of the third mirror surface is 228.00 to 232.54 mm, the mirror spacing of the third mirror surface is 12.56 to 14.23 mm, and the effective light aperture of the third mirror surface is 24.31 to 26.78 mm; the curvature radius of the fourth mirror surface is -403.51 to -430.25 mm, the mirror spacing of the fourth mirror surface is 12.50 to 15.04 mm, and the effective light aperture of the fourth mirror surface is 24.88 to 26.67 mm;

[0028] The curvature radius of the fifth mirror surface is -142.68 to -128.50 mm, the mirror spacing of the fifth mirror surface is 7.85 to 8.96 mm, and the effective clear aperture of the fifth mirror surface is 24.35 to 26.34 mm; the curvature radius of the sixth mirror surface is 152.47 to 165.25 mm, the mirror spacing of the sixth mirror surface is 6.75 to 9.21 mm, and the effective clear aperture of the sixth mirror surface is 24.65 to 26.85 mm;

[0029] The curvature radius of the seventh mirror surface is -352.70 to -337.68 mm, the mirror spacing of the seventh mirror surface is 12.70 to 14.21 mm, and the effective clear aperture of the seventh mirror surface is 25.65 to 27.81 mm; the curvature radius of the eighth mirror surface is 109.80 to 117.65 mm, the mirror spacing of the eighth mirror surface is 2.32 to 3.11 mm, and the effective clear aperture of the eighth mirror surface is 29.17 to 31.55 mm;

[0030] The curvature radius of the ninth mirror surface is 138.25 to 140.20 mm, the mirror spacing of the ninth mirror surface is 14.50 to 15.23 mm, and the effective clear aperture of the ninth mirror surface is 29.56 to 31.19 mm; the curvature radius of the tenth mirror surface is -114.22 to -112.95 mm, the mirror spacing of the tenth mirror surface is 36.78 to 38.95 mm, and the effective clear aperture of the tenth mirror surface is 30.65 to 32.85 mm;

[0031] The curvature radius of the eleventh mirror is -70.82 to -68.54 mm, the mirror spacing of the eleventh mirror is 10.54 to 13.20 mm, and the effective light-clearance aperture of the eleventh mirror is 33.54 to 35.12 mm; the curvature radius of the twelfth mirror is -70.45 to -67.55 mm, the mirror spacing of the twelfth mirror is 145.34 to 152.91 mm, and the effective light-clearance aperture of the twelfth mirror is 36.11 to 37.65 mm.

[0032] Preferably, the mirror surface of the seventh lens facing the object side is convex, and the mirror surface facing the image side is concave;

[0033] Both mirror surfaces of the eighth lens are convex;

[0034] Both mirror surfaces of the ninth lens are concave;

[0035] Both mirror surfaces of the tenth lens are concave;

[0036] Both mirror surfaces of the eleventh lens are convex surfaces;

[0037] Both mirror surfaces of the twelfth lens are convex surfaces.

[0038] Preferably, the seventh lens includes a thirteenth mirror surface and a fourteenth mirror surface; the thirteenth mirror surface is the mirror surface of the seventh lens facing the object side, and the fourteenth mirror surface is the mirror surface of the seventh lens facing the image side;

[0039] The eighth lens includes a fifteenth mirror surface and a sixteenth mirror surface; the fifteenth mirror surface is the mirror surface of the eighth lens facing the object side, and the sixteenth mirror surface is the mirror surface of the eighth lens facing the image side;

[0040] The ninth lens includes a seventeenth mirror surface and an eighteenth mirror surface; the seventeenth mirror surface is the mirror surface of the ninth lens facing the object side, and the eighteenth mirror surface is the mirror surface of the ninth lens facing the image side;

[0041] The tenth lens includes a nineteenth mirror surface and a twentieth mirror surface; the nineteenth mirror surface is the mirror surface of the tenth lens facing the object side, and the twentieth mirror surface is the mirror surface of the tenth lens facing the image side;

[0042] The eleventh lens includes a twenty-first mirror surface and a twenty-second mirror surface; the twenty-first mirror surface is the mirror surface of the eleventh lens facing the object side, and the twenty-second mirror surface is the mirror surface of the eleventh lens facing the image side;

[0043] The twelfth lens includes a twenty-third mirror surface and a twenty-fourth mirror surface; the twenty-third mirror surface is the mirror surface of the twelfth lens facing the object side, and the twenty-fourth mirror surface is the mirror surface of the twelfth lens facing the image side;

[0044] The curvature radius of the thirteenth mirror surface is -70.45 to -67.55 mm, the mirror spacing of the thirteenth mirror surface is 145.34 to 152.91 mm, and the effective clear aperture of the thirteenth mirror surface is 36.11 to 37.65 mm; the curvature radius of the fourteenth mirror surface is -70.82 to -68.54 mm, the mirror spacing of the fourteenth mirror surface is 10.54 to 13.20 mm, and the effective clear aperture of the fourteenth mirror surface is 33.54 to 35.12 mm;

[0045] The curvature radius of the fifteenth mirror surface is -114.22 to -112.95 mm, the mirror spacing of the fifteenth mirror surface is 36.78 to 38.95 mm, and the effective clear aperture of the fifteenth mirror surface is 30.65 to 32.85 mm; the curvature radius of the sixteenth mirror surface is 138.25 to 140.20 mm, the mirror spacing of the sixteenth mirror surface is 14.50 to 15.23 mm, and the effective clear aperture of the sixteenth mirror surface is 29.56 to 31.19 mm;

[0046] The curvature radius of the seventeenth mirror surface is 109.80 to 117.65 mm, the mirror spacing of the seventeenth mirror surface is 2.32 to 3.11 mm, and the effective light aperture of the seventeenth mirror surface is 29.17 to 31.55 mm; the curvature radius of the eighteenth mirror surface is -352.70 to -337.68 mm, the mirror spacing of the eighteenth mirror surface is 12.70 to 14.21 mm, and the effective light aperture of the eighteenth mirror surface is 25.65 to 27.81 mm;

[0047] The curvature radius of the nineteenth mirror surface is 152.47 to 165.25 mm, the mirror spacing of the nineteenth mirror surface is 6.75 to 9.21 mm, and the effective clear aperture of the nineteenth mirror surface is 24.65 to 26.85 mm; the curvature radius of the twentieth mirror surface is -142.68 to -128.50 mm, the mirror spacing of the twentieth mirror surface is 7.85 to 8.96 mm, and the effective clear aperture of the twentieth mirror surface is 24.35 to 26.34 mm;

[0048] The curvature radius of the 21st mirror surface is -403.51 to -430.25 mm, the mirror spacing of the 21st mirror surface is 12.50 to 15.04 mm, and the effective clear aperture of the 21st mirror surface is 24.88 to 26.67 mm; the curvature radius of the 22nd mirror surface is 228.00 to 232.54 mm, the mirror spacing of the 22nd mirror surface is 12.56 to 14.23 mm, and the effective clear aperture of the 22nd mirror surface is 24.31 to 26.78 mm;

[0049] The curvature radius of the 23rd mirror is -327.40 to -323.20 mm, the mirror spacing of the 23rd mirror is 90.74 to 95.34 mm, and the effective light aperture of the 23rd mirror is 20.66 to 22.43 mm; the curvature radius of the 24th mirror is 733.29 to 742.50 mm, the mirror spacing of the 24th mirror is 13.10 to 15.90 mm, and the effective light aperture of the 24th mirror is 20.54 to 21.65 mm.

[0050] Preferably, the focal length of the first lens is 301.66 mm, the focal length of the second lens is 229.52 mm, the focal length of the third lens is -102.55 mm, the focal length of the fourth lens is ~119.41 mm, the focal length of the fifth lens is 85.47 mm, the focal length of the sixth lens is 949.10 mm, the focal length of the seventh lens is 949.10 mm, the focal length of the eighth lens is 85.47 mm, the focal length of the ninth lens is -119.41 mm, the focal length of the tenth lens is ~102.55 mm, the focal length of the eleventh lens is 229.52 mm, and the focal length of the twelfth lens is 301.66 mm.

[0051] Preferably, the refractive index / Abbe coefficient of the first lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the second lens is 1.65 / 55.9, the refractive index / Abbe coefficient of the third lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the fourth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the fifth lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the sixth lens is 1.76 / 27.5, the refractive index / Abbe coefficient of the seventh lens is 1.76 / 27.5, the refractive index / Abbe coefficient of the eighth lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the ninth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the tenth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the eleventh lens is 1.65 / 55.9, and the refractive index / Abbe coefficient of the twelfth lens is 1.74 / 44.9.

[0052] Preferably, the numerical aperture of the collimating lens group is greater than or equal to 0.12 and less than 0.15.

[0053] Preferably, the distance from the object-side rear surface of the entrance slit to the object-side front end surface of the first lens of the collimating lens group is greater than or equal to 170 mm and less than 185 mm.

[0054] The embodiment of the present application provides a symmetrical, flat-field, non-glued Raman spectrometer optical system, comprising a collimating lens group and an imaging lens group arranged on the same optical axis, wherein the lenses in the collimating lens group and the lenses in the imaging lens group are arranged on the same optical axis, and similarly, each lens group includes lenses with both sides being concave and both sides being convex. In this solution, the focal points of different Raman wavelengths still present a planar state when the image plane is unfolded, perpendicular to the optical axis, and very consistent with the current detector imaging target surface being a plane. In addition, in this solution, the structural form reduces processing costs and assembly difficulty in a completely symmetrical form between the imaging lens group and the collimating lens group, and the structure does not contain glue for gluing the lenses, and will not introduce additional Raman signals spontaneously generated by the glue, thereby achieving the technical requirements of symmetry, flat field, and non-gluing. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0056] Figure 1 A schematic diagram of a symmetrical, flat-field, non-glued Raman spectrometer optical system provided in an embodiment of the present application;

[0057] Figure 2a This is a light spot diagram of 650nm Raman wavelength when the 590nm Raman wavelength falls on the center of the detector under the 600gr / mm grating of the optical system provided in an embodiment of the present application;

[0058] Figure 2b A transfer function diagram of the optical system provided in an embodiment of the present application at a Raman wavelength of 650 nm when the Raman wavelength of 590 nm falls at the center of the detector under a 600 gr / mm grating;

[0059] Figure 3a A light spot diagram of 590nm Raman wavelength when the optical system provided by an embodiment of the present application falls at the center of the detector under a 600gr / mm grating;

[0060] Figure 3b A transfer function diagram of the optical system provided in an embodiment of the present application at a Raman wavelength of 590 nm when the Raman wavelength falls at the center of the detector under a 600 gr / mm grating;

[0061] Figure 4a This is a diagram of the light spots of 530nm Raman wavelength when the 590nm Raman wavelength falls on the center of the detector under the 600gr / mm grating of the optical system provided in an embodiment of the present application;

[0062] Figure 4b A transfer function diagram of a Raman wavelength of 530 nm for the optical system provided in an embodiment of the present application when a Raman wavelength of 590 nm falls at the center of the detector under a 600 gr / mm grating;

[0063] Figure 5 The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 650nm, 650nm±0.2nm, and 590nm Raman wavelength falling at the center of the detector under a 600gr / mm grating.

[0064] Figure 6The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 590 nm and 590 nm ± 0.2 nm, when the 590 nm Raman wavelength falls at the center of the detector under a 600 gr / mm grating;

[0065] Figure 7 The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 530 nm and 530 nm ± 0.2 nm, when the 590 nm Raman wavelength falls at the center of the detector under a 600 gr / mm grating;

[0066] Figure 8a A light spot diagram of a 650nm Raman wavelength when a 623.5nm Raman wavelength falls at the center of the detector under a 1200gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0067] Figure 8b A transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 650 nm when the Raman wavelength of 623.5 nm falls at the center of the detector under a 1200 gr / mm grating;

[0068] Figure 9a A light spot diagram of a symmetrical, flat-field, non-glued Raman spectrometer optical system provided by an embodiment of the present invention, with a 623.5 nm Raman wavelength falling at the center of the detector under a 1200 gr / mm grating;

[0069] Figure 9b A transfer function diagram of the 623.5 nm Raman wavelength of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention when the 623.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating;

[0070] Figure 10a A light spot diagram of a 597nm Raman wavelength when a 623.5nm Raman wavelength falls at the center of the detector under a 1200gr / mm grating for the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0071] Figure 10b A transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 597 nm when the Raman wavelength of 623.5 nm falls at the center of the detector under a 1200 gr / mm grating;

[0072] Figure 11The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 650 nm, 650 nm ± 0.08 nm, and 623.5 nm at the center of the detector under a 1200 gr / mm grating.

[0073] Figure 12 The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 623.5 nm and 623.5 nm ± 0.08 nm, when the 623.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating;

[0074] Figure 13 The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths of 597 nm ± 0.08 nm when the Raman wavelength of 623.5 nm falls at the center of the detector under a 1200 gr / mm grating;

[0075] Figure 14a A light spot diagram of a 589nm Raman wavelength when a 561.5nm Raman wavelength falls at the center of the detector under a 1200gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0076] Figure 14b A graph showing the Raman wavelength transfer function at 589 nm for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a 1200 gr / mm grating and a Raman wavelength of 561.5 nm falling at the center of the detector;

[0077] Figure 15a A light spot diagram of a 561.5 nm Raman wavelength when the 561.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating for the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0078] Figure 15b A transfer function diagram of the 561.5 nm Raman wavelength of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention when the 561.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating;

[0079] Figure 16a A light spot diagram of a 534nm Raman wavelength when a 561.5nm Raman wavelength falls at the center of the detector under a 1200gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0080] Figure 16bA transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 534 nm when the Raman wavelength of 561.5 nm falls at the center of the detector under a 1200 gr / mm grating;

[0081] Figure 17 1 is a point diagram of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 561.5 nm falling at the center of the detector under a 1200 gr / mm grating, at three Raman wavelengths: 589 nm and 589 nm ± 0.08 nm.

[0082] Figure 18 1 is a point diagram of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, when the 561.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating, at three Raman wavelengths: 561.5 nm and 561.5 nm ± 0.08 nm.

[0083] Figure 19 1 is a point diagram of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 561.5 nm falling at the center of the detector under a 1200 gr / mm grating, at three Raman wavelengths: 534 nm and 534 nm ± 0.08 nm.

[0084] Figure 20a A light spot diagram of a 650nm Raman wavelength when a 637nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating for the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0085] Figure 20b A transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 650 nm and a Raman wavelength of 637 nm falling at the center of the detector under an 1800 gr / mm grating;

[0086] Figure 21a A light spot diagram of a symmetrical, flat-field, non-glued Raman spectrometer optical system provided by an embodiment of the present invention, with a 637 nm Raman wavelength falling at the center of the detector under an 1800 gr / mm grating;

[0087] Figure 21b A transfer function diagram of the 637 nm Raman wavelength of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention when the 637 nm Raman wavelength falls at the center of the detector under an 1800 gr / mm grating;

[0088] Figure 22aA light spot diagram of a 624nm Raman wavelength when a 637nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0089] Figure 22b A transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 624 nm when the Raman wavelength of 637 nm falls at the center of the detector under an 1800 gr / mm grating;

[0090] See also Figure 23 1 is a point diagram of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, when the 637 nm Raman wavelength falls at the center of the detector under an 1800 gr / mm grating, at three Raman wavelengths: 650 nm and 650 nm ± 0.045 nm;

[0091] See also Figure 24 1 is a point diagram of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, when the 637 nm Raman wavelength falls at the center of the detector under an 1800 gr / mm grating at three Raman wavelengths: 637 nm and 637 nm ± 0.045 nm;

[0092] See also Figure 25 1 is a point diagram of the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 637 nm falling at the center of the detector under an 1800 gr / mm grating, at three Raman wavelengths: 624 nm and 624 nm ± 0.045 nm;

[0093] Figure 26a A light spot diagram of a 604nm Raman wavelength when a 549nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0094] Figure 26b A transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 604 nm when the Raman wavelength of 549 nm falls at the center of the detector under an 1800 gr / mm grating;

[0095] Figure 27a A light spot diagram of a 590nm Raman wavelength when a 549nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0096] Figure 27bA transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 549 nm falling at the center of the detector under an 1800 gr / mm grating, at a Raman wavelength of 590 nm;

[0097] Figure 28a A light spot diagram of a 576nm Raman wavelength when a 549nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating for the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention;

[0098] Figure 28b A transfer function diagram of the optical system of a symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention, with a Raman wavelength of 549 nm falling at the center of the detector under an 1800 gr / mm grating, at a Raman wavelength of 576 nm;

[0099] Figure 29 The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 604 nm and 604 nm ± 0.045 nm, when the Raman wavelength of 549 nm falls at the center of the detector under an 1800 gr / mm grating;

[0100] Figure 30 The optical system of the symmetrical, flat-field, un-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 549 nm and 549 nm ± 0.045 nm, when the 549 nm Raman wavelength falls at the center of the detector under an 1800 gr / mm grating;

[0101] Figure 31 The optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 534 nm and 534 nm ± 0.045 nm when the 549 nm Raman wavelength falls at the center of the detector under an 1800 gr / mm grating. DETAILED DESCRIPTION

[0102] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0103] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0104] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components; wireless connections or wired connections. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0105] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0106] Example 1

[0107] The present invention provides a symmetrical, flat-field, non-glued Raman spectrometer optical system to overcome the problem in conventional optical systems where the focal points of different Raman wavelengths present a curved surface when the image plane is unfolded (i.e., the image plane is not flat), which is contrary to the current technical problem that the detector imaging target surface is flat. For details, see Figure 1 As shown, the embodiment of the present application provides a symmetrical, flat-field, non-glued Raman spectrometer optical system, comprising:

[0108] A collimating lens group 11 composed of a first number of lenses arranged on the same optical axis, and an imaging lens group 12 composed of a second number of lenses arranged on the same optical axis, arranged sequentially from the object side to the image side;

[0109] The collimating lens group 11 and the imaging lens group 12 each include at least one lens with both sides being convex and at least one lens with both sides being concave;

[0110] The lenses in the collimating lens group and the lenses in the imaging lens group are arranged on the same optical axis.

[0111] In one embodiment, the first number and the second number are both 6;

[0112] The lenses constituting the collimating lens group are the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5 and the sixth lens L6;

[0113] The lenses constituting the imaging lens group are seventh lens L7, eighth lens L8, ninth lens L9, tenth lens L10, eleventh lens L11 and twelfth lens L12.

[0114] Furthermore, in the embodiments of the present application,

[0115] Both mirror surfaces of the first lens L1 are convex;

[0116] Both mirror surfaces of the second lens L2 are convex;

[0117] Both mirror surfaces of the third lens L3 are concave;

[0118] Both mirror surfaces of the fourth lens L4 are concave;

[0119] Both mirror surfaces of the fifth lens L5 are convex;

[0120] One mirror surface of the sixth lens L6 is convex, and the other mirror surface is concave. The sixth lens L6 has a concave surface facing the object side and a convex surface facing the image side.

[0121] Furthermore, in the embodiments of the present application,

[0122] The first lens L1 includes a first mirror surface and a second mirror surface; the first mirror surface is the mirror surface of the first lens facing the object side, and the second mirror surface is the mirror surface of the first lens facing the image side;

[0123] The second lens L2 includes a third mirror surface and a fourth mirror surface; the third mirror surface is the mirror surface of the second lens facing the object side, and the fourth mirror surface is the mirror surface of the second lens facing the image side;

[0124] The third lens L3 includes a fifth mirror surface and a sixth mirror surface; the fifth mirror surface is the mirror surface of the third lens facing the object side, and the sixth mirror surface is the mirror surface of the third lens facing the image side;

[0125] The fourth lens L4 includes a seventh mirror surface and an eighth mirror surface; the seventh mirror surface is the mirror surface of the fourth lens facing the object side, and the eighth mirror surface is the mirror surface of the fourth lens facing the image side;

[0126] The fifth lens L5 includes a ninth mirror surface and a tenth mirror surface; the ninth mirror surface is the mirror surface of the fifth lens facing the object side, and the tenth mirror surface is the mirror surface of the fifth lens facing the image side;

[0127] The sixth lens L6 includes an eleventh mirror surface and a twelfth mirror surface; the eleventh mirror surface is the mirror surface of the sixth lens facing the object side, and the twelfth mirror surface is the mirror surface of the sixth lens facing the image side;

[0128] The curvature radius of the first mirror is 733.29 to 742.50 mm, the mirror spacing of the first mirror is 13.10 to 15.90 mm, and the effective clear aperture of the first mirror is 20.54 to 21.65 mm; the curvature radius of the second mirror is -327.40 to -323.20 mm, the mirror spacing of the second mirror is 90.74 to 95.34 mm, and the effective clear aperture of the second mirror is 20.66 to 22.43 mm;

[0129] The curvature radius of the third mirror surface is 228.00 to 232.54 mm, the mirror spacing of the third mirror surface is 12.56 to 14.23 mm, and the effective light aperture of the third mirror surface is 24.31 to 26.78 mm; the curvature radius of the fourth mirror surface is -403.51 to -430.25 mm, the mirror spacing of the fourth mirror surface is 12.50 to 15.04 mm, and the effective light aperture of the fourth mirror surface is 24.88 to 26.67 mm;

[0130] The curvature radius of the fifth mirror surface is -142.68 to -128.50 mm, the mirror spacing of the fifth mirror surface is 7.85 to 8.96 mm, and the effective clear aperture of the fifth mirror surface is 24.35 to 26.34 mm; the curvature radius of the sixth mirror surface is 152.47 to 165.25 mm, the mirror spacing of the sixth mirror surface is 6.75 to 9.21 mm, and the effective clear aperture of the sixth mirror surface is 24.65 to 26.85 mm;

[0131] The curvature radius of the seventh mirror surface is -352.70 to -337.68 mm, the mirror spacing of the seventh mirror surface is 12.70 to 14.21 mm, and the effective clear aperture of the seventh mirror surface is 25.65 to 27.81 mm; the curvature radius of the eighth mirror surface is 109.80 to 117.65 mm, the mirror spacing of the eighth mirror surface is 2.32 to 3.11 mm, and the effective clear aperture of the eighth mirror surface is 29.17 to 31.55 mm;

[0132] The curvature radius of the ninth mirror surface is 138.25 to 140.20 mm, the mirror spacing of the ninth mirror surface is 14.50 to 15.23 mm, and the effective clear aperture of the ninth mirror surface is 29.56 to 31.19 mm; the curvature radius of the tenth mirror surface is -114.22 to -112.95 mm, the mirror spacing of the tenth mirror surface is 36.78 to 38.95 mm, and the effective clear aperture of the tenth mirror surface is 30.65 to 32.85 mm;

[0133] The curvature radius of the eleventh mirror is -70.82 to -68.54 mm, the mirror spacing of the eleventh mirror is 10.54 to 13.20 mm, and the effective light-clearance aperture of the eleventh mirror is 33.54 to 35.12 mm; the curvature radius of the twelfth mirror is -70.45 to -67.55 mm, the mirror spacing of the twelfth mirror is 145.34 to 152.91 mm, and the effective light-clearance aperture of the twelfth mirror is 36.11 to 37.65 mm.

[0134] In the embodiments of this application,

[0135] The mirror surface of the seventh lens facing the object side is convex, and the mirror surface facing the image side is concave;

[0136] Both mirror surfaces of the eighth lens are convex;

[0137] Both mirror surfaces of the ninth lens are concave;

[0138] Both mirror surfaces of the tenth lens are concave;

[0139] Both mirror surfaces of the eleventh lens are convex surfaces;

[0140] Both mirror surfaces of the twelfth lens are convex surfaces.

[0141] Furthermore, in the embodiments of the present application,

[0142] The seventh lens includes a thirteenth mirror surface and a fourteenth mirror surface; the thirteenth mirror surface is the mirror surface of the seventh lens facing the object side, and the fourteenth mirror surface is the mirror surface of the seventh lens facing the image side;

[0143] The eighth lens includes a fifteenth mirror surface and a sixteenth mirror surface; the fifteenth mirror surface is the mirror surface of the eighth lens facing the object side, and the sixteenth mirror surface is the mirror surface of the eighth lens facing the image side;

[0144] The ninth lens includes a seventeenth mirror surface and an eighteenth mirror surface; the seventeenth mirror surface is the mirror surface of the ninth lens facing the object side, and the eighteenth mirror surface is the mirror surface of the ninth lens facing the image side;

[0145] The tenth lens includes a nineteenth mirror surface and a twentieth mirror surface; the nineteenth mirror surface is the mirror surface of the tenth lens facing the object side, and the twentieth mirror surface is the mirror surface of the tenth lens facing the image side;

[0146] The eleventh lens includes a twenty-first mirror surface and a twenty-second mirror surface; the twenty-first mirror surface is the mirror surface of the eleventh lens facing the object side, and the twenty-second mirror surface is the mirror surface of the eleventh lens facing the image side;

[0147] The twelfth lens includes a twenty-third mirror surface and a twenty-fourth mirror surface; the twenty-third mirror surface is the mirror surface of the twelfth lens facing the object side, and the twenty-fourth mirror surface is the mirror surface of the twelfth lens facing the image side;

[0148] The curvature radius of the thirteenth mirror surface is -70.45 to -67.55 mm, the mirror spacing of the thirteenth mirror surface is 145.34 to 152.91 mm, and the effective clear aperture of the thirteenth mirror surface is 36.11 to 37.65 mm; the curvature radius of the fourteenth mirror surface is -70.82 to -68.54 mm, the mirror spacing of the fourteenth mirror surface is 10.54 to 13.20 mm, and the effective clear aperture of the fourteenth mirror surface is 33.54 to 35.12;

[0149] The curvature radius of the fifteenth mirror surface is -114.22 to -112.95 mm, the mirror spacing of the fifteenth mirror surface is 36.78 to 38.95 mm, and the effective clear aperture of the fifteenth mirror surface is 30.65 to 32.85 mm; the curvature radius of the sixteenth mirror surface is 138.25 to 140.20 mm, the mirror spacing of the sixteenth mirror surface is 14.50 to 15.23 mm, and the effective clear aperture of the sixteenth mirror surface is 29.56 to 31.19 mm;

[0150] The curvature radius of the seventeenth mirror surface is 109.80 to 117.65 mm, the mirror spacing of the seventeenth mirror surface is 2.32 to 3.11 mm, and the effective light aperture of the seventeenth mirror surface is 29.17 to 31.55 mm; the curvature radius of the eighteenth mirror surface is -352.70 to -337.68 mm, the mirror spacing of the eighteenth mirror surface is 12.70 to 14.21 mm, and the effective light aperture of the eighteenth mirror surface is 25.65 to 27.81 mm;

[0151] The curvature radius of the nineteenth mirror surface is 152.47 to 165.25 mm, the mirror spacing of the nineteenth mirror surface is 6.75 to 9.21 mm, and the effective clear aperture of the nineteenth mirror surface is 24.65 to 26.85 mm; the curvature radius of the twentieth mirror surface is -142.68 to -128.50 mm, the mirror spacing of the twentieth mirror surface is 7.85 to 8.96 mm, and the effective clear aperture of the twentieth mirror surface is 24.35 to 26.34 mm;

[0152] The curvature radius of the 21st mirror surface is -403.51 to -430.25 mm, the mirror spacing of the 21st mirror surface is 12.50 to 15.04 mm, and the effective clear aperture of the 21st mirror surface is 24.88 to 26.67 mm; the curvature radius of the 22nd mirror surface is 228.00 to 232.54 mm, the mirror spacing of the 22nd mirror surface is 12.56 to 14.23 mm, and the effective clear aperture of the 22nd mirror surface is 24.31 to 26.78 mm;

[0153] The curvature radius of the 23rd mirror is -327.40 to -323.20 mm, the mirror spacing of the 23rd mirror is 90.74 to 95.34 mm, and the effective light aperture of the 23rd mirror is 20.66 to 22.43 mm; the curvature radius of the 24th mirror is 733.29 to 742.50 mm, the mirror spacing of the 24th mirror is 13.10 to 15.90 mm, and the effective light aperture of the 24th mirror is 20.54 to 21.65 mm.

[0154] In this embodiment of the present application, the focal length of the first lens is 301.66 mm, the focal length of the second lens is 229.52 mm, the focal length of the third lens is -102.55 mm, the focal length of the fourth lens is -119.41 mm, the focal length of the fifth lens is 85.47 mm, the focal length of the sixth lens is 949.10 mm, the focal length of the seventh lens is 949.10 mm, the focal length of the eighth lens is 85.47 mm, the focal length of the ninth lens is -119.41 mm, the focal length of the tenth lens is -102.55 mm, the focal length of the eleventh lens is 229.52 mm, and the focal length of the twelfth lens is 301.66 mm.

[0155] In the embodiment of the present application, the refractive index / Abbe coefficient of the first lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the second lens is 1.65 / 55.9, the refractive index / Abbe coefficient of the third lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the fourth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the fifth lens is 1.74 / 44.9, and the refractive index / Abbe coefficient of the sixth lens is 1.76 / 27.5, the refractive index / Abbe coefficient of the seventh lens is 1.76 / 27.5, the refractive index / Abbe coefficient of the eighth lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the ninth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the tenth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the eleventh lens is 1.65 / 55.9, and the refractive index / Abbe coefficient of the twelfth lens is 1.74 / 44.9.

[0156] In the embodiment of the present application, the numerical aperture of the collimating lens group is greater than or equal to 0.12 and less than 0.15.

[0157] In the embodiment of the present application, the distance from the entrance slit away from the object-side rear surface to the object-side front end surface of the first lens of the collimating lens group is greater than or equal to 170 mm and less than 185 mm.

[0158] The symmetrical, flat-field, and glue-free Raman spectrometer optical system provided in the embodiments of the present application can achieve aberration correction, including spherical aberration, coma, astigmatism, field curvature, distortion, etc., to meet the requirements of a flat-field Raman spectrometer optical system. The structural form uses a completely symmetrical form of the imaging lens group and the collimating lens group to reduce processing costs and assembly difficulty. The structure does not contain glue for gluing lenses, and will not introduce additional Raman signals spontaneously generated by the glue, thereby achieving the technical requirements of symmetry, flat field, and glue-free. At the same time, the image quality index of the optical system provided in the embodiment of the present application is that the spectral resolution is better than 0.2nm at a groove density of 600gr / mm, the spectral resolution is better than 0.08nm at a groove density of 1200gr / mm, and the spectral resolution is better than 0.045nm at a groove density of 1800gr / mm. It should be noted that the actual grating can be set according to actual needs. If the Raman signal coverage range within a single field of view of the optical system detector is desired to be large and the spectral resolution requirement is not considered, a grating with a smaller groove density can be selected. Conversely, if a higher spectral resolution is required but the coverage range of the Raman signal within a single field of view of the detector is not considered, a grating with a higher groove density can be selected.

[0159] Several specific embodiments of the symmetrical, flat-field, and glue-free Raman spectrometer optical system provided by the embodiments of the present application are listed below: Specific embodiment 1:

[0161] See also Figure 2a 、 Figure 2b 、 Figure 3a 、 Figure 3b 、 Figure 4a and Figure 4b As shown, they are the spot diagrams and transfer function diagrams of 650nm Raman wavelength, 590nm Raman wavelength and 530nm Raman wavelength when the 590nm Raman wavelength falls on the center of the detector under the 600gr / mm grating of the optical system provided by the embodiment of the present application, respectively. Figure 2a This is a spot diagram showing the image of an ideal object point at a Raman wavelength of 650nm after imaging through the entire optical system (with a plane grating with a groove density of 600gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 650nm is 9.349μm, and the image point size within the 100% energy range is 27.905μm, demonstrating excellent aberration balance and imaging. Figure 2b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 2a and Figure 2b It can be concluded that the transfer function curves in the meridional and sagittal directions of the 650nm Raman wavelength are close to the diffraction limit, indicating that the imaging contrast of the optical system at the 650nm Raman wavelength is extremely high and the imaging layering is clear. Figure 3a A spot diagram showing the light spot size at a 590 nm Raman wavelength after an ideal object point is imaged by the optical system provided by this application (the plane grating has a groove density of 600 gr / mm). The figure shows that the RMS image point size of the ideal object point at a 590 nm Raman wavelength is 14.151 μm, and the image point size within the 100% energy range is 17.659 μm, indicating good aberration balance and excellent imaging. Figure 3b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 3a and Figure 3b It can be concluded that the transfer function curves in the meridian and sagittal directions of the 590nm Raman wavelength are greater than 0.3 at 40lp / mm, indicating that the imaging contrast of the optical system at the 590nm Raman wavelength is very high and the imaging layering is clear. Figure 4a This is a spot diagram showing the image of an ideal object point at a 530nm Raman wavelength after imaging through the entire optical system (with a plane grating with a groove density of 600gr / mm). The figure shows that the RMS image size of the ideal object point at a 530nm Raman wavelength is 8.054μm, and the image size within the 100% energy range is 13.606μm, demonstrating excellent aberration balance and imaging. Figure 4bThe vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 4a and Figure 4b It shows that the transfer function curves of the meridian and sagittal directions of the 590nm Raman wavelength are greater than 0.6 at 40lp / mm, indicating that the imaging contrast of the optical system at the 530nm Raman wavelength is very high and the imaging layering is clear. Figure 2a 、 Figure 2b 、 Figure 3a 、 Figure 3b 、 Figure 4a and Figure 4b It can be concluded that when the 590nm Raman wavelength falls at the center of the detector under the 600gr / mm grating, the optical system provided in the embodiment of the present application has high imaging contrast at the 650nm Raman wavelength, 590nm Raman wavelength and 530nm Raman wavelength, and the imaging layering is clear.

[0162] Figure 5 The optical system of the symmetrical, flat-field, unbonded Raman spectrometer provided in an embodiment of the present invention shows a point diagram of three Raman wavelengths: 650nm, 650nm±0.2nm, and 590nm Raman wavelength falling at the center of the detector under a 600gr / mm grating. The middle point is the image point formed by the 650nm Raman wavelength, the upper point is the image point formed by the 650.2nm Raman wavelength, and the lower point is the image point formed by the 649.8nm Raman wavelength. As can be seen from the figure, when the central Raman wavelength is 650nm, two adjacent Raman wavelengths of 0.2nm are completely separable, indicating that the Raman spectral resolution of the embodiment of the present invention is at least better than 0.2nm under a 600gr / mm grating. Figure 6 The optical system of the symmetrical, flat-field, unbonded Raman spectrometer provided in an embodiment of the present invention shows a point diagram of three Raman wavelengths: 590nm, 590nm±0.2nm, when the 590nm Raman wavelength falls at the center of the detector under a 600gr / mm grating. The middle point is the image point formed by the 590nm Raman wavelength, the upper point is the image point formed by the 590.2nm Raman wavelength, and the lower point is the image point formed by the 589.8nm Raman wavelength. The figure shows that when the central Raman wavelength is 590nm, two adjacent Raman wavelengths of 0.2nm are completely separable, indicating that the Raman spectral resolution of the embodiment of the present invention is at least better than 0.2nm under a 600gr / mm grating. Figure 7The optical system of the symmetrical, flat-field, unbonded Raman spectrometer provided in an embodiment of the present invention shows a point diagram of three Raman wavelengths: 530nm, 530nm±0.2nm, when the 590nm Raman wavelength falls at the center of the detector under a 600gr / mm grating. The middle point is the image point formed by the 530nm Raman wavelength, the upper point is the image point formed by the 530.2nm Raman wavelength, and the lower point is the image point formed by the 529.8nm Raman wavelength. The figure shows that when the central Raman wavelength is 530nm, two adjacent Raman wavelengths of 0.2nm are completely separable, indicating that the Raman spectral resolution of the embodiment of the present invention is at least better than 0.2nm under a 600gr / mm grating.

[0163] Combine Figure 5 、 Figure 6 and Figure 7 It can be concluded that the optical system provided in the embodiment of the present application can completely separate two adjacent Raman wavelengths of 0.2 nm under a 600 gr / mm grating. Therefore, it can be determined that the Raman spectral resolution is at least better than 0.2 nm under a 600 gr / mm grating.

[0164] In the examples of this application, see Figure 8a 、 Figure 8b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 650nm Raman wavelength when the 623.5nm Raman wavelength falls on the center of the detector under a 1200gr / mm grating. Figure 8a This figure shows the spot size of an ideal object point at a Raman wavelength of 650nm after imaging through the entire optical system (the plane grating has a groove density of 1200gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 650nm is 9.224μm, and the image point size within the 100% energy range is 26.142μm, indicating very good aberration balance and excellent imaging. Figure 8b The vertical axis is the normalized OTF mode, and the horizontal axis is the spatial frequency, in lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. The figure shows that the transfer function curves in the meridional and sagittal directions of the 650nm Raman wavelength are close to the diffraction limit. Figure 8a 、 Figure 8b This shows that the imaging contrast of the optical system at 650nm Raman wavelength is extremely high, and the image layering is clear. Figure 9a 、 Figure 9b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of the 623.5nm Raman wavelength when the 623.5nm Raman wavelength falls on the center of the detector under a 1200gr / mm grating. Figure 8aThis is a spot diagram showing the image of an ideal object point at a Raman wavelength of 623.5 nm after imaging through the entire optical system (with a plane grating with a groove density of 1200 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 623.5 nm is 6.561 μm, and the image point size within the 100% energy range is 10.618 μm, demonstrating excellent aberration balance and imaging. Figure 9b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 9a 、 Figure 9b It shows that the transfer function curves in the meridian and sagittal directions of the 623.5nm Raman wavelength are close to the diffraction limit, indicating that the imaging contrast of the optical system at the 623.5nm Raman wavelength is extremely high and the imaging layering is clear. Figure 10a 、 Figure 10b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 597nm Raman wavelength when the 623.5nm Raman wavelength falls on the center of the detector under a 1200gr / mm grating. Figure 10a This figure shows the spot size of an ideal object point at a Raman wavelength of 597 nm after imaging through the entire optical system (the plane grating has a groove density of 1200 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 597 nm is 17.455 μm, and the image point size within the 100% energy range is 22.410 μm, indicating good aberration balance and excellent imaging. Figure 10b The vertical axis represents the normalized OTF modulus, and the horizontal axis represents spatial frequency (lp / mm). The solid line represents the meridional transfer function curve, and the dashed line represents the sagittal transfer function curve. The figure shows that the meridional and sagittal transfer function curves for the 597nm Raman wavelength are greater than 0.1 at 40 lp / mm, indicating that the optical system has high image contrast and distinct depth at this 597nm Raman wavelength.

[0165] Therefore, comprehensive Figure 8a 、 Figure 8b 、 Figure 9a 、 Figure 9b and Figure 10a 、 Figure 10b It can be concluded that when the 623.5nm Raman wavelength falls at the center of the detector under the 1200gr / mm grating, the optical system provided by the embodiment of the present application has high imaging contrast at the 650nm, 623.5nm Raman wavelengths, and 597nm Raman wavelengths, and the imaging layering is clear.

[0166] See also Figure 11As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 650nm, 650nm±0.08nm when the Raman wavelength of 623.5nm falls at the center of the detector under a 1200gr / mm grating. The middle point is the image point formed by the Raman wavelength of 650nm, the upper point is the image point formed by the Raman wavelength of 650.08nm, and the lower point is the image point formed by the Raman wavelength of 649.92nm. It can be seen from the figure that when the central Raman wavelength is 650nm, two adjacent Raman wavelengths of 0.08nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.08nm under a 1200gr / mm grating.

[0167] See also Figure 12 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 623.5nm and 623.5nm±0.08nm when the 623.5nm Raman wavelength falls at the center of the detector under a 1200gr / mm grating. The middle point is the image point of the 623.5nm Raman wavelength, the upper point is the image point of the 623.5nm Raman wavelength, and the lower point is the image point of the 623.42nm Raman wavelength. It can be seen from the figure that when the central Raman wavelength is 623.5nm, two adjacent Raman wavelengths of 0.08nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.08nm under a 1200gr / mm grating.

[0168] See also Figure 13 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths of 597nm±0.08nm when the Raman wavelength of 623.5nm falls at the center of the detector under a 1200gr / mm grating. The middle point is the image point of the 597nm Raman wavelength, the upper point is the image point of the 597.08nm Raman wavelength, and the lower point is the image point of the 596.92nm Raman wavelength. It can be seen from the figure that when the central Raman wavelength is 597nm, the two adjacent Raman wavelengths of 0.08nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.08nm under a 1200gr / mm grating.

[0169] Therefore, combined Figure 11 、 Figure 12 and Figure 13 It can be concluded that the Raman spectrum resolution of the optical system provided in the embodiment of the present application is at least better than 0.08 nm at a 1200 gr / mm grating.

[0170] In the examples of this application, see Figure 14a 、 Figure 14bAs shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 589nm Raman wavelength when the 561.5nm Raman wavelength falls on the center of the detector under a 1200gr / mm grating. Figure 14a This figure shows the spot size of an ideal object point at a Raman wavelength of 589 nm after imaging through the entire optical system (the plane grating has a groove density of 1200 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 589 nm is 18.772 μm, and the image point size within the 100% energy range is 23.833 μm, indicating good aberration balance and excellent imaging. Figure 14b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 14a 、 Figure 14b It can be concluded that the transfer function curves in the meridian and sagittal directions at the Raman wavelength of 589nm are both greater than 0.1 at 40lp / mm, indicating that the imaging contrast of the optical system at this Raman wavelength is high and the imaging layering is clear.

[0171] In the examples of this application, see Figure 15a 、 Figure 15b As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of 561.5nm Raman wavelength when the 561.5nm Raman wavelength falls on the center of the detector under a 1200gr / mm grating. Figure 15a This is a spot diagram showing the image of an ideal object point at a Raman wavelength of 561.5 nm after imaging through the entire optical system (with a plane grating with a groove density of 1200 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 561.5 nm is 12.554 μm, and the image point size within the 100% energy range is 15.722 μm, indicating well-balanced aberrations and excellent imaging. Figure 15b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 15a 、 Figure 15b It can be shown that the transfer function curves in the meridian and sagittal directions of the 561.5nm Raman wavelength are both greater than 0.45 at 40lp / mm, indicating that the imaging contrast of the optical system at this Raman wavelength is very high and the imaging layering is clear.

[0172] In the examples of this application, see Figure 16a 、 Figure 16bAs shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 534nm Raman wavelength when the 561.5nm Raman wavelength falls on the center of the detector under a 1200gr / mm grating. Figure 16a This figure shows the spot size of an ideal object point at a 534nm Raman wavelength after imaging through the entire optical system (with a plane grating with a groove density of 1200gr / mm). The figure shows that the RMS image point size of the ideal object point at a 534nm Raman wavelength is 5.762μm, and the image point size within the 100% energy range is 9.623μm, demonstrating excellent aberration balance and imaging. Figure 16b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 16a and Figure 16b It can be concluded that the transfer function curves in the meridional and sagittal directions at the 534nm Raman wavelength are close to the diffraction limit, indicating that the imaging contrast of the optical system at this Raman wavelength is extremely high and the imaging layering is clear.

[0173] Therefore, combined Figure 14a 、 Figure 14b 、 Figure 15a 、 Figure 15b and Figure 16a 、 Figure 16b It can be concluded that when the 561.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating, the optical system provided by the embodiment of the present invention has extremely high imaging contrast at the 589 nm Raman wavelength, the 561.5 nm Raman wavelength, and the 534 nm Raman wavelength, and the imaging layering is clear.

[0174] See also Figure 17 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 589nm and 589nm±0.08nm, when the Raman wavelength of 561.5nm falls on the center of the detector under a 1200gr / mm grating. The middle point is the image point of the Raman wavelength of 589nm, the upper point is the image point of the Raman wavelength of 589.08nm, and the lower point is the image point of the Raman wavelength of 588.92nm. Figure 17 It can be seen that when the central Raman wavelength is 589 nm, two adjacent Raman wavelengths of 0.08 nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.08 nm under a 1200 gr / mm grating.

[0175] See also Figure 18As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 561.5 nm and 561.5 nm ± 0.08 nm, when the 561.5 nm Raman wavelength falls at the center of the detector under a 1200 gr / mm grating. The middle point is the image point formed by the 561.5 nm Raman wavelength, the upper point is the image point formed by the 561.58 nm Raman wavelength, and the lower point is the image point formed by the 561.42 nm Raman wavelength. Figure 18 It can be seen that when the central Raman wavelength is 561.5 nm, two adjacent Raman wavelengths of 0.08 nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.08 nm under a 1200 gr / mm grating.

[0176] See also Figure 19 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 534nm and 534nm±0.08nm, when the Raman wavelength of 561.5nm falls on the center of the detector under a 1200gr / mm grating. The middle point is the image point of the Raman wavelength of 534nm, the upper point is the image point of the Raman wavelength of 534.08nm, and the lower point is the image point of the Raman wavelength of 533.92nm. Figure 19 It can be seen that when the central Raman wavelength is 534 nm, two adjacent Raman wavelengths of 0.08 nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.08 nm under a 1200 gr / mm grating.

[0177] Combine Figure 17 、 Figure 18 and Figure 19 It can be concluded that the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by the embodiment of the present invention has a Raman spectrum resolution of at least better than 0.08 nm at a 1200 gr / mm grating.

[0178] See also Figure 20a 、 Figure 20b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 650nm Raman wavelength when the 637nm Raman wavelength falls on the center of the detector under an 1800gr / mm grating. Figure 20a This figure shows the spot size of an ideal object point at a Raman wavelength of 650nm after imaging through the entire optical system (the plane grating has a groove density of 1800gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 650nm is 11.027μm, and the image point size within the 100% energy range is 33.128μm, indicating good aberration balance and excellent imaging. Figure 20bThe vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 20a 、 Figure 20b It shows that the transfer function curves in the meridian and sagittal directions of the 650nm Raman wavelength are both greater than 0.6 at 40lp / mm, indicating that the imaging contrast of the optical system at this Raman wavelength is very high and the imaging layering is clear.

[0179] See also Figure 21a 、 Figure 21b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of the 637nm Raman wavelength when the 637nm Raman wavelength falls on the center of the detector under an 1800gr / mm grating. Figure 21a This figure shows the spot size of an ideal object point at a Raman wavelength of 637 nm after imaging through the entire optical system (with a plane grating with a groove density of 1800 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 637 nm is 6.816 μm, and the image point size within the 100% energy range is 21.727 μm, indicating very good aberration balance and excellent imaging. Figure 21b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 21a 、 Figure 21b It shows that the transfer function curves in the meridian and sagittal directions of the 637nm Raman wavelength are close to the diffraction limit, indicating that the imaging contrast of the optical system at this Raman wavelength is extremely high and the imaging layering is clear.

[0180] See also Figure 22a 、 Figure 22b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 624nm Raman wavelength when the 637nm Raman wavelength falls on the center of the detector under an 1800gr / mm grating. Figure 22a This figure shows the spot size of an ideal object point at a Raman wavelength of 624 nm after imaging through the entire optical system (the plane grating has a groove density of 1800 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 624 nm is 9.965 μm, and the image point size within the 100% energy range is 14.634 μm, indicating good aberration balance and imaging quality. Figure 22b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 22a 、 Figure 22b It shows that the transfer function curves in the meridian and sagittal directions of the 624nm Raman wavelength are both greater than 0.5 at 40lp / mm, indicating that the imaging contrast of the optical system at the 624nm Raman wavelength is very high and the imaging layering is clear.

[0181] Therefore, combined Figure 20a 、 Figure 20b 、 Figure 21a 、 Figure 21b 、 Figure 22a 、 Figure 22b It can be concluded that the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by the embodiment of the present invention has very high imaging contrast at 650nm Raman wavelength, 637nm Raman wavelength, and 624nm Raman wavelength when the 637nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating, and the imaging layering is clear.

[0182] See also Figure 23 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 650nm, 650nm±0.045nm when the Raman wavelength of 637nm falls at the center of the detector under an 1800gr / mm grating. The middle point is the image point formed by the Raman wavelength of 650nm, the upper point is the image point formed by the Raman wavelength of 650.045nm, and the lower point is the image point formed by the Raman wavelength of 649.955nm. It can be seen from the figure that when the central Raman wavelength is 650nm, two adjacent Raman wavelengths of 0.045nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045nm under an 1800gr / mm grating.

[0183] See also Figure 24 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 637nm and 637nm±0.045nm when the 637nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating. The middle point is the image point formed by the 637nm Raman wavelength, the upper point is the image point formed by the 637.045nm Raman wavelength, and the lower point is the image point formed by the 636.955nm Raman wavelength. It can be seen from the figure that when the central Raman wavelength is 637nm, the two adjacent Raman wavelengths of 0.045nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045nm under the 1800gr / mm grating.

[0184] See also Figure 25As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 624nm and 624nm±0.045nm when the Raman wavelength of 637nm falls at the center of the detector under an 1800gr / mm grating. The middle point is the image point formed by the Raman wavelength of 624nm, the upper point is the image point formed by the Raman wavelength of 624.045nm, and the lower point is the image point formed by the Raman wavelength of 623.995nm. It can be seen from the figure that when the central Raman wavelength is 624nm, two adjacent Raman wavelengths of 0.045nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045nm under an 1800gr / mm grating.

[0185] Combine Figure 23 、 Figure 24 and Figure 25 It can be concluded that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045 nm under 1800 gr / mm grating.

[0186] See also Figure 26a 、 Figure 26b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 604nm Raman wavelength when the 549nm Raman wavelength falls on the center of the detector under an 1800gr / mm grating. Figure 26a This figure shows the spot size of an ideal object point at a Raman wavelength of 604 nm after imaging through the entire optical system (the plane grating has a groove density of 1800 gr / mm). The figure shows that the RMS image point size of the ideal object point at a Raman wavelength of 604 nm is 17.113 μm, and the image point size within the 100% energy range is 21.379 μm, indicating good aberration balance and excellent imaging. Figure 26b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 26a 、 Figure 26b , indicating that the transfer function curves in the meridian and sagittal directions of the 604nm Raman wavelength are both greater than 0.1 at 40lp / mm, indicating that the imaging contrast of the optical system at the 604nm Raman wavelength is high and the imaging layering is clear.

[0187] See also Figure 27a 、 Figure 27b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 590nm Raman wavelength when the 549nm Raman wavelength falls on the center of the detector under an 1800gr / mm grating. Figure 27aThis is a spot diagram showing the image of an ideal object point at a 590nm Raman wavelength after imaging through the entire optical system (with a plane grating with a groove density of 1800gr / mm). The figure shows that the RMS image size of the ideal object point at a 590nm Raman wavelength is 7.962μm, and the image size within the 100% energy range is 11.276μm, demonstrating excellent aberration balance and imaging. Figure 27b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 27a 、 Figure 27b It shows that the transfer function curves in the meridian and sagittal directions at the Raman wavelength of 590nm are close to the diffraction limit, indicating that the imaging contrast of the optical system at the Raman wavelength of 590nm is extremely high and the imaging layering is clear.

[0188] See also Figure 28a 、 Figure 28b As shown, the optical system of the symmetrical, flat field, non-glued Raman spectrometer provided by an embodiment of the present invention is a light spot array diagram and a transfer function diagram of a 576nm Raman wavelength when the 549nm Raman wavelength falls on the center of the detector under an 1800gr / mm grating. Figure 28a This figure shows the spot size of an ideal object point at a 576nm Raman wavelength after imaging through the entire optical system (the plane grating has a groove density of 1800gr / mm). The figure shows that the RMS image point size of the ideal object point at a 576nm Raman wavelength is 6.110μm, and the image point size within the 100% energy range is 11.085μm, indicating very good aberration balance and excellent imaging. Figure 28b The vertical axis is the normalized OTF modulus, and the horizontal axis is the spatial frequency, in units of lp / mm. The solid line is the transfer function curve in the meridional direction, and the dotted line is the transfer function curve in the sagittal direction. Figure 28a 、 Figure 28b It shows that the transfer function curves in the meridian and sagittal directions of the 576nm Raman wavelength are close to the diffraction limit, indicating that the imaging contrast of the optical system at the 576nm Raman wavelength is extremely high and the imaging layering is clear.

[0189] Combine Figure 27a 、 Figure 27b 、 Figure 28a 、 Figure 28b It can be concluded that the optical system provided in the embodiment of the present application has extremely high imaging contrast when the 549nm Raman wavelength falls on the 590nm Raman wavelength and the 576nm Raman wavelength under the 1800gr / mm grating, and the imaging layering is clear.

[0190] See also Figure 29As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 604nm and 604nm±0.045nm when the Raman wavelength of 549nm falls at the center of the detector under an 1800gr / mm grating. The middle point is the image point formed by the Raman wavelength of 604nm, the upper point is the image point formed by the Raman wavelength of 604.045nm, and the lower point is the image point formed by the Raman wavelength of 603.955nm. It can be seen from the figure that when the central Raman wavelength is 604nm, the two adjacent Raman wavelengths of 0.045nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045nm under the 1800gr / mm grating.

[0191] See also Figure 30 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention is a point diagram of three Raman wavelengths: 549nm, 549nm±0.045nm when the 549nm Raman wavelength falls at the center of the detector under an 1800gr / mm grating. The middle point is the image point of the 549nm Raman wavelength, the upper point is the image point of the 549nm Raman wavelength, and the lower point is the image point of the 548.955nm Raman wavelength. It can be seen from the figure that when the central Raman wavelength is 549nm, the two adjacent Raman wavelengths of 0.045nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045nm under the 1800gr / mm grating.

[0192] See also Figure 31 As shown, the optical system of the symmetrical, flat-field, non-glued Raman spectrometer provided by an embodiment of the present invention shows a point diagram of three Raman wavelengths: 534nm and 534nm±0.045nm when the Raman wavelength of 549nm falls at the center of the detector under an 1800gr / mm grating. The middle point is the image point of the Raman wavelength of 534nm, the upper point is the image point of the Raman wavelength of 534.045nm, and the lower point is the image point of the Raman wavelength of 533.995nm. It can be seen from the figure that when the central Raman wavelength is 534nm, the two adjacent Raman wavelengths of 0.045nm are completely separable, indicating that the Raman spectrum resolution of the embodiment of the present invention is at least better than 0.045nm under the 1800gr / mm grating.

[0193] The embodiment of the present application provides a symmetrical, flat-field, non-glued Raman spectrometer optical system, comprising a collimating lens group and an imaging lens group arranged on the same optical axis, wherein the lenses in the collimating lens group and the lenses in the imaging lens group are arranged on the same optical axis, and similarly, each lens group includes lenses with both sides being concave and both sides being convex. In this solution, the focal points of different Raman wavelengths still present a planar state when the image plane is unfolded, perpendicular to the optical axis, and very consistent with the current detector imaging target surface being a plane. In addition, in this solution, the structural form reduces processing costs and assembly difficulty in a completely symmetrical form between the imaging lens group and the collimating lens group, and the structure does not contain glue for gluing the lenses, and will not introduce additional Raman signals spontaneously generated by the glue, thereby achieving the technical requirements of symmetry, flat field, and non-gluing.

[0194] The optical system of the symmetrical, flat-field, unbonded Raman spectrometer provided in the embodiments of the present application can achieve complete separation of two adjacent Raman wavelengths within a certain range. The above embodiments are merely for the purpose of illustrating that the optical system provided in the embodiments of the present application can achieve complete separation of two adjacent Raman wavelengths within a certain range within the wavelength range of 540nm to 650nm, and do not specifically limit the wavelength range to 540nm to 650nm. It is noted that, based on the optical system of the symmetrical, flat-field, unbonded Raman spectrometer provided in the present application, inventive changes to the optical system itself by merely changing the grating, wavelength range, or spacing between two adjacent wavelengths still fall within the scope of protection of the embodiments of the present application.

[0195] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A symmetrical, flat field, non-glued Raman spectrometer optical system, characterized in that: include: A collimating lens group consisting of six lenses arranged on the same optical axis, and an imaging lens group consisting of six lenses arranged on the same optical axis, which are arranged in sequence from the object side to the image side; The six lenses arranged on the same optical axis and the six lenses arranged on the same optical axis each include at least one lens with both sides convex and at least one lens with both sides concave; The lenses in the collimating lens group and the lenses in the imaging lens group are arranged on the same optical axis; The lenses constituting the collimating lens group are a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens; The lenses constituting the imaging lens group are the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens and the twelfth lens; The first lens includes a first mirror surface and a second mirror surface; the first mirror surface is the mirror surface of the first lens facing the object side, and the second mirror surface is the mirror surface of the first lens facing the image side; The second lens includes a third mirror surface and a fourth mirror surface; the third mirror surface is the mirror surface of the second lens facing the object side, and the fourth mirror surface is the mirror surface of the second lens facing the image side; The third lens includes a fifth mirror surface and a sixth mirror surface; the fifth mirror surface is the mirror surface of the third lens facing the object side, and the sixth mirror surface is the mirror surface of the third lens facing the image side; The fourth lens includes a seventh mirror surface and an eighth mirror surface; the seventh mirror surface is the mirror surface of the fourth lens facing the object side, and the eighth mirror surface is the mirror surface of the fourth lens facing the image side; The fifth lens includes a ninth mirror surface and a tenth mirror surface; the ninth mirror surface is the mirror surface of the fifth lens facing the object side, and the tenth mirror surface is the mirror surface of the fifth lens facing the image side; The sixth lens includes an eleventh mirror surface and a twelfth mirror surface; the eleventh mirror surface is the mirror surface of the sixth lens facing the object side, and the twelfth mirror surface is the mirror surface of the sixth lens facing the image side; The curvature radius of the first mirror is 733.29 to 742.50 mm, the mirror spacing of the first mirror is 13.10 to 15.90 mm, and the effective clear aperture of the first mirror is 20.54 to 21.65 mm; the curvature radius of the second mirror is -327.40 to -323.20 mm, the mirror spacing of the second mirror is 90.74 to 95.34 mm, and the effective clear aperture of the second mirror is 20.66 to 22.43 mm; The curvature radius of the third mirror surface is 228.00 to 232.54 mm, the mirror spacing of the third mirror surface is 12.56 to 14.23 mm, and the effective light aperture of the third mirror surface is 24.31 to 26.78 mm; the curvature radius of the fourth mirror surface is -403.51 to -430.25 mm, the mirror spacing of the fourth mirror surface is 12.50 to 15.04 mm, and the effective light aperture of the fourth mirror surface is 24.88 to 26.67 mm; The curvature radius of the fifth mirror surface is -142.68 to -128.50 mm, the mirror spacing of the fifth mirror surface is 7.85 to 8.96 mm, and the effective clear aperture of the fifth mirror surface is 24.35 to 26.34 mm; the curvature radius of the sixth mirror surface is 152.47 to 165.25 mm, the mirror spacing of the sixth mirror surface is 6.75 to 9.21 mm, and the effective clear aperture of the sixth mirror surface is 24.65 to 26.85 mm; The curvature radius of the seventh mirror surface is -352.70 to -337.68 mm, the mirror spacing of the seventh mirror surface is 12.70 to 14.21 mm, and the effective clear aperture of the seventh mirror surface is 25.65 to 27.81 mm; the curvature radius of the eighth mirror surface is 109.80 to 117.65 mm, the mirror spacing of the eighth mirror surface is 2.32 to 3.11 mm, and the effective clear aperture of the eighth mirror surface is 29.17 to 31.55 mm; The curvature radius of the ninth mirror surface is 138.25 to 140.20 mm, the mirror spacing of the ninth mirror surface is 14.50 to 15.23 mm, and the effective clear aperture of the ninth mirror surface is 29.56 to 31.19 mm; the curvature radius of the tenth mirror surface is -114.22 to -112.95 mm, the mirror spacing of the tenth mirror surface is 36.78 to 38.95 mm, and the effective clear aperture of the tenth mirror surface is 30.65 to 32.85 mm; The curvature radius of the eleventh mirror is -70.82 to -68.54 mm, the mirror spacing of the eleventh mirror is 10.54 to 13.20 mm, and the effective light-clearance aperture of the eleventh mirror is 33.54 to 35.12 mm; the curvature radius of the twelfth mirror is -70.45 to -67.55 mm, the mirror spacing of the twelfth mirror is 145.34 to 152.91 mm, and the effective light-clearance aperture of the twelfth mirror is 36.11 to 37.65 mm.

2. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 1, characterized in that: Both mirror surfaces of the first lens are convex; Both mirror surfaces of the second lens are convex; Both mirror surfaces of the third lens are concave; Both mirror surfaces of the fourth lens are concave; Both mirror surfaces of the fifth lens are convex; One mirror surface of the sixth lens is convex, and the other mirror surface is concave. The sixth lens has a concave surface facing the object side and a convex surface facing the image side.

3. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 1, characterized in that: The mirror surface of the seventh lens facing the object side is convex, and the mirror surface facing the image side is concave; Both mirror surfaces of the eighth lens are convex; Both mirror surfaces of the ninth lens are concave; Both mirror surfaces of the tenth lens are concave; Both mirror surfaces of the eleventh lens are convex surfaces; Both mirror surfaces of the twelfth lens are convex surfaces.

4. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 3, characterized in that: The seventh lens includes a thirteenth mirror surface and a fourteenth mirror surface; the thirteenth mirror surface is the mirror surface of the seventh lens facing the object side, and the fourteenth mirror surface is the mirror surface of the seventh lens facing the image side; The eighth lens includes a fifteenth mirror surface and a sixteenth mirror surface; the fifteenth mirror surface is the mirror surface of the eighth lens facing the object side, and the sixteenth mirror surface is the mirror surface of the eighth lens facing the image side; The ninth lens includes a seventeenth mirror surface and an eighteenth mirror surface; the seventeenth mirror surface is the mirror surface of the ninth lens facing the object side, and the eighteenth mirror surface is the mirror surface of the ninth lens facing the image side; The tenth lens includes a nineteenth mirror surface and a twentieth mirror surface; the nineteenth mirror surface is the mirror surface of the tenth lens facing the object side, and the twentieth mirror surface is the mirror surface of the tenth lens facing the image side; The eleventh lens includes a twenty-first mirror surface and a twenty-second mirror surface; the twenty-first mirror surface is the mirror surface of the eleventh lens facing the object side, and the twenty-second mirror surface is the mirror surface of the eleventh lens facing the image side; The twelfth lens includes a twenty-third mirror surface and a twenty-fourth mirror surface; the twenty-third mirror surface is the mirror surface of the twelfth lens facing the object side, and the twenty-fourth mirror surface is the mirror surface of the twelfth lens facing the image side; The curvature radius of the thirteenth mirror surface is -70.45 to -67.55 mm, the mirror spacing of the thirteenth mirror surface is 145.34 to 152.91 mm, and the effective clear aperture of the thirteenth mirror surface is 36.11 to 37.65 mm; the curvature radius of the fourteenth mirror surface is -70.82 to -68.54 mm, the mirror spacing of the fourteenth mirror surface is 10.54 to 13.20 mm, and the effective clear aperture of the fourteenth mirror surface is 33.54 to 35.12; The curvature radius of the fifteenth mirror surface is -114.22 to -112.95 mm, the mirror spacing of the fifteenth mirror surface is 36.78 to 38.95 mm, and the effective clear aperture of the fifteenth mirror surface is 30.65 to 32.85 mm; the curvature radius of the sixteenth mirror surface is 138.25 to 140.20 mm, the mirror spacing of the sixteenth mirror surface is 14.50 to 15.23 mm, and the effective clear aperture of the sixteenth mirror surface is 29.56 to 31.19 mm; The curvature radius of the seventeenth mirror surface is 109.80 to 117.65 mm, the mirror spacing of the seventeenth mirror surface is 2.32 to 3.11 mm, and the effective light aperture of the seventeenth mirror surface is 29.17 to 31.55 mm; the curvature radius of the eighteenth mirror surface is -352.70 to -337.68 mm, the mirror spacing of the eighteenth mirror surface is 12.70 to 14.21 mm, and the effective light aperture of the eighteenth mirror surface is 25.65 to 27.81 mm; The curvature radius of the nineteenth mirror surface is 152.47 to 165.25 mm, the mirror spacing of the nineteenth mirror surface is 6.75 to 9.21 mm, and the effective clear aperture of the nineteenth mirror surface is 24.65 to 26.85 mm; the curvature radius of the twentieth mirror surface is -142.68 to -128.50 mm, the mirror spacing of the twentieth mirror surface is 7.85 to 8.96 mm, and the effective clear aperture of the twentieth mirror surface is 24.35 to 26.34 mm; The curvature radius of the 21st mirror surface is -403.51 to -430.25 mm, the mirror spacing of the 21st mirror surface is 12.50 to 15.04 mm, and the effective clear aperture of the 21st mirror surface is 24.88 to 26.67 mm; the curvature radius of the 22nd mirror surface is 228.00 to 232.54 mm, the mirror spacing of the 22nd mirror surface is 12.56 to 14.23 mm, and the effective clear aperture of the 22nd mirror surface is 24.31 to 26.78 mm; The curvature radius of the 23rd mirror is -327.40 to -323.20 mm, the mirror spacing of the 23rd mirror is 90.74 to 95.34 mm, and the effective light aperture of the 23rd mirror is 20.66 to 22.43 mm; the curvature radius of the 24th mirror is 733.29 to 742.50 mm, the mirror spacing of the 24th mirror is 13.10 to 15.90 mm, and the effective light aperture of the 24th mirror is 20.54 to 21.65 mm.

5. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 1, characterized in that: The focal length of the first lens is 301.66 mm, the focal length of the second lens is 229.52 mm, the focal length of the third lens is -102.55 mm, the focal length of the fourth lens is ~119.41 mm, the focal length of the fifth lens is 85.47 mm, the focal length of the sixth lens is 949.10 mm, the focal length of the seventh lens is 949.10 mm, the focal length of the eighth lens is 85.47 mm, the focal length of the ninth lens is -119.41 mm, the focal length of the tenth lens is -102.55 mm, the focal length of the eleventh lens is 229.52 mm, and the focal length of the twelfth lens is 301.66 mm.

6. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 1, characterized in that: The refractive index / Abbe coefficient of the first lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the second lens is 1.65 / 55.9, the refractive index / Abbe coefficient of the third lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the fourth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the fifth lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the sixth lens is 1.76 / 27.5, the refractive index / Abbe coefficient of the seventh lens is 1.76 / 27.5, the refractive index / Abbe coefficient of the eighth lens is 1.74 / 44.9, the refractive index / Abbe coefficient of the ninth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the tenth lens is 1.69 / 31.2, the refractive index / Abbe coefficient of the eleventh lens is 1.65 / 55.9, and the refractive index / Abbe coefficient of the twelfth lens is 1.74 / 44.

9.

7. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 1, characterized in that: The numerical aperture of the collimating lens group is greater than or equal to 0.12 and less than 0.

15.

8. The symmetrical, flat field, glueless Raman spectrometer optical system according to claim 1, characterized in that: The distance from the rear surface of the incident slit away from the object side to the object side front end surface of the first lens of the collimating lens group is greater than or equal to 170 mm and less than 185 mm.

Images