CN113568101B - Polarization-dependent infrared narrow-band filter and preparation method thereof - Google Patents
Polarization-dependent infrared narrow-band filter and preparation method thereof Download PDFInfo
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Abstract
The invention relates to two distributed Bragg reflectors and a defect layer positioned between the two distributed Bragg reflectors; the defect layer comprises a metal nanorod array and a transparent high polymer material coated outside the metal nanorod array. The infrared filter structure formed by the structure has the polarization direction of filtering determined by the direction of the metal nano-rods in the defect layer, and the peak position determined by the thickness of the defect layer. The invention combines the traditional distributed Bragg reflector with a super surface structure to realize 1300-1500nm;1400-1650nm polarization dependent transmission narrow band filtering. And because the DBR and the super surface are microscopic structures, the whole volume of the narrow-band filter can realize small integration, and the narrow-band filter is more suitable for integrated application in the industry at present.
Description
Technical Field
The invention relates to the technical field of optical filters, in particular to an infrared narrow-band filter with polarization dependence and a preparation method thereof.
Background
Nowadays, the social information communication is rapidly developed, and from the first 2G to the third 3G and the fourth 4G, large-area laying of 5G communication is started in many countries. This undoubtedly facilitates the work and life of people. Filters are important parts for identifying wavelengths in communication equipment, so that research on different optical filters is crucial to promote industrial development.
An optical filter is a selective element of optical wavelengths. There are a number of ways in which optical wavelength selection can be achieved: the traditional prism can lead the light with different wavelengths to generate dispersion, thereby achieving the result of light selection; the traditional grating can enhance the diffraction of light with different wavelengths in different directions, and light selection is realized. In addition, optical filtering can also be achieved by means of interference: different thicknesses and refractive indexes of the Bragg distributed reflectors (DBRs) are designed, and transmission or reflection enhancement of light is achieved, so that a frequency selection result is achieved. Generally, the distributed Bragg reflector of the multilayer dielectric film can realize broadband filtering, and the prior art mainly realizes narrow-band transmission in a broadband low-pass region of the DBR by inserting a defect layer in the middle of the DBRNarrow-band filtering can then be achieved within this band-pass filtering frequency range. As shown in fig. 1, the dbr is mainly composed of a dielectric material 1 with a high refractive index and a dielectric material 2 with a low refractive index, which are alternately stacked, and a defect layer 3 (usually a dielectric material with a low refractive index, without absorption loss) of different materials is added to realize narrow-band filtering, and the central wavelength of the narrow-band filtering and the peak value of the transmission peak can be modulated by changing the thickness of the defect layer 3, as shown in fig. 2. Because the defect layer 3 has no polarization relation, the filter has no polarization selectivity; wherein the thickness of the defective layer 3
The values of m are different, the used film layer dielectric materials and the thicknesses of the defect layers are different, and the center wavelengths of the frequency selection are also different (see left side a and right side b maps of figure 2: the influence of different defect layer thicknesses on the narrow-band filter).
The above methods are currently mainstream filter design methods, and relatively speaking, the optical filters designed by these design concepts are large, poor in integration, and generally large in filter width. According to research and research, the filter technology disclosed at present has a wide half-wave width ratio of narrow-band filtering near 1550nm, and cannot realize low half-wave width and high transmittance at the same time. Furthermore, such prior art solutions also do not enable polarization dependent transmission filtering.
Disclosure of Invention
Technical problem to be solved
In view of the above disadvantages and shortcomings of the prior art, the present invention provides a polarization-dependent infrared narrowband filter, which combines a conventional Distributed Bragg Reflector (Distributed Bragg Reflector) with a super-surface structure to implement polarization-dependent transmission narrowband filtering and small integration, and is more suitable for the integrated application in the industry at present. The invention also relates to a preparation method of the polarization-dependent infrared narrow-band filter.
(II) technical scheme
In order to achieve the purpose, the invention adopts the main technical scheme that:
in a first aspect, the present invention provides a polarization dependent infrared narrow band filter comprising:
the optical device comprises two distributed Bragg reflectors and a defect layer positioned between the two distributed Bragg reflectors; the defect layer comprises a metal nanorod array and a transparent high polymer material coated outside the metal nanorod array.
Preferably, the thickness of the defect layer is adjustable. The infrared filter structure formed by the structure has the advantages that the polarization direction of filtering is determined by the direction of the metal nanorods in the defect layer, and the peak position is determined by the thickness of the defect layer. The thickness of the defect layer is mainly realized by adjusting the thickness of the transparent high polymer material.
According to the preferred embodiment of the invention, the two pieces of distributed Bragg reflectors respectively comprise a silicon chip substrate and a silicon dioxide film and a silicon film which are alternately grown on the silicon chip substrate.
According to the preferred embodiment of the invention, three layers of silicon dioxide films and three layers of silicon films are alternately grown on the silicon wafer substrate, and the total thickness of the silicon dioxide films and the silicon films is six. Specifically, a silicon dioxide film (a dielectric material with a low refractive index), a silicon film (a dielectric material with a high refractive index), a silicon dioxide film, a silicon dioxide film, and a silicon film are sequentially provided on a silicon wafer substrate. The larger the number of DBR layers, the higher the reflectivity, and the narrower the full width at half maximum of the narrow band filter, but when the reflectivity is close to 100%, the narrow band filter fails. I.e., the number of DBR layers needs to be within a reasonable range.
According to the preferred embodiment of the present invention, the two dbr layers have the same structure, wherein the refractive index of the silica film is 1.46, and the refractive index of the silicon film is 3.49; the thickness of each thin film is 240-320nm, preferably 290nm. The absorption of light by the two materials in the near infrared band is negligible.
Silica has a refractive index of 1.46 in the near infrared region, an extinction coefficient of 0, and is substantially free of dispersion. The amorphous silicon near-infrared refractive index is 3.49, the extinction coefficient is 0, and the dispersion relation is not obvious.
The two distributed Bragg reflectors are respectively and symmetrically contacted with the defect layer through the topmost silicon film; sandwiching a defect layer between two DBR mirrors; and the silicon chip substrates of the two distributed Bragg reflectors are positioned on two outer side surfaces of the filter. The required bandwidth of the DBR can be realized when the thickness of each thin film is 240-320nm, and 290nm is preferred.
According to the preferred embodiment of the present invention, the metal nanorod array is an array composed of gold nanorods, and the metal nanorods may also be made of metal such as silver, aluminum, platinum, etc., but different metal materials may cause the frequency of the narrow band filter to have some movement with the change of the materials.
According to the preferred embodiment of the invention, the gold nanorod array is formed on the surface of one of the distributed bragg reflectors, and the transparent polymer material is coated outside the gold nanorod array.
According to the preferred embodiment of the invention, the transparent polymer material is PMMA, AS, transparent ABS, PC or PS; most preferably it is PMMA. The transparent high polymer material mainly plays a role in fixing and packaging the metal nanorod array and adjusting the whole thickness of the defect layer, but the transparent high polymer material can be any dielectric material with high transparency, low refractive index and no absorption loss. In the preferred embodiment, since PMMA has a low glass softening temperature and a small expansion coefficient, it can be filled in a predetermined shape, and the thickness and shape can be precisely controlled, which is easy to be practically operated.
Of these, PMMA has a refractive index of 1.48 in the near infrared spectrum, and the absorption coefficient is negligible. The PMMA transmittance can reach more than 92 percent, the glass transition temperature is low, the water absorption and expansion coefficient are low, the size and the shape are stable, and the like. The lower glass transition temperature can avoid the influence on the metal nanorod array when the metal nanorod array is encapsulated and coated.
According to a preferred embodiment of the present invention, the defect layer further includes a transparent film laminated on the surface of the transparent polymer material, and a sum of the thickness of the transparent film and the thickness of the transparent polymer material determines the thickness of the defect layer. The transparent film material is a dielectric material with high transparency, low refractive index and no absorption loss.
According to the preferred embodiment of the invention, the size of each gold nanorod in the gold nanorod array is 220-300nm in length, 80nm in width and 200nm in thickness; the period of the gold nanorod array is 640nm. When the conditions are met, the simulation result is excellent.
According to a preferred embodiment of the invention, the thickness of the defect layer is 550-900nm, preferably 550-700nm or 700-900nm.
More preferably, the size of each gold nanorod in the gold nanorod array is 220nm, the width of each gold nanorod is 80nm, the thickness of each gold nanorod is 200nm, the array period is 640nm, and the thickness of the defect layer is 550-700nm; or the size of a single gold nanorod in the gold nanorod array is 300nm, the width of the single gold nanorod is 80nm, the thickness of the single gold nanorod is 200nm, the period of the array is 640nm, and the thickness of the defect layer is 700-900nm.
In a second aspect, the present invention further provides a method for preparing a polarization-dependent infrared narrow-band filter, which includes:
s1, preparing two distributed Bragg reflectors;
s2, forming a metal nanorod array on the surface of one of the distributed Bragg reflectors;
s3, filling softened transparent high polymer materials around and on the metal nanorod array, and curing after filling;
and S4, inverting the other distributed Bragg reflector on the transparent high polymer material.
Preferably, the two pieces of distributed bragg reflectors have the same structure, and include a silicon wafer substrate, and a silicon dioxide film and a silicon film alternately grown on the silicon wafer substrate.
In S2, the metal nanorod array may be formed in the following manner: the method comprises the steps of coating photoresist (such as electron beam resist) on the surface of a distributed Bragg reflector, writing a preset structure by adopting photoetching (or electron beam), carrying out development operation, wherein the preset structure comprises an array formed by a plurality of rod-shaped (long and short axis figures) figure units, evaporating a metal material (preferably gold), stripping the photoresist (such as the electron beam resist) (adopting photoresist removing liquid) and washing (acetone) after evaporation, and forming a super-surface structure formed by the metal nanorod array on the surface of the distributed Bragg reflector.
(III) advantageous effects
Compared with the prior art, the invention has the main technical effects that:
(1) The invention combines the traditional Distributed Bragg Reflector (Distributed Bragg Reflector) with a super-surface structure to realize 1300-1500nm;1400-1650nm polarization dependent transmission narrow band filtering. And because the DBR and the super surface are microscopic structures, the whole volume of the narrow-band filter can realize small integration, and the narrow-band filter is more suitable for integrated application in the industry at present. The polarization direction of the infrared filter structure is determined by the direction of the metal nano-rods in the defect layer, and the peak position is determined by the thickness of the defect layer. Therefore, the invention can realize polarization-dependent narrow-band filtering; wherein the polarization direction of the narrow-band transmission is consistent with the short axis of the gold nanorod.
(2) In the invention, when the width of a single gold nanorod of the gold nanorod super-surface array is 80nm, the thickness is 200nm, and the period is 640nm; when the length is 220nm and the thickness of the defect layer (transparent high polymer material) is increased in the range of 550-700nm, the peak position of the transmitted light is gradually red-shifted in the range of 1300-1500nm; the transmissivity exceeds 80 percent, and the half-wave width is less than 8nm; when the length is 300nm and the thickness of the defect layer (transparent high polymer material) is increased in the range of 700-900nm, the peak position of the transmitted light gradually red-shifts in the range of 1400-1650 nm; the transmissivity exceeds 80 percent, and the half-wave width is less than 8nm. Therefore, the invention realizes low half wave width and high transmittance at the same time.
Drawings
Fig. 1 is a schematic structural diagram of a conventional DBR with a narrow-band filter implemented by introducing defect layers of different materials in the middle of the DBR.
Fig. 2 is a graph showing the effect of the thickness of a defective layer on a narrow band filter in the conventional filter shown in fig. 1.
Fig. 3 is a schematic structural diagram of the polarization-dependent infrared narrow-band filter of the present invention.
FIG. 4 is a dispersion diagram of the refractive index and absorption coefficient of gold in the infrared narrow band filter in the examples.
FIG. 5 is a filter spectrum (a) of x polarization direction and a filter spectrum (b) of y polarization direction when the length of a single gold nanorod in the gold nano array is 220 nm.
FIG. 6 is a filter spectrum (a) in the x-polarization direction and a filter spectrum (b) in the y-polarization direction when the length of a single gold nanorod in the gold nano-array is 300 nm.
Detailed Description
For a better understanding of the present invention, reference will now be made in detail to the present embodiments of the invention, which are illustrated in the accompanying drawings.
The super-surface structure is a sub-wavelength micro-structure array which is manually arranged, each micro-structure can be regarded as an electromagnetic wave regulation and control unit, and the regulation and control of the phase, amplitude, polarization and the like of electromagnetic waves at corresponding positions can be realized, so that the properties of emergent light waves can be regulated and controlled. The main idea of the invention is to combine the traditional Distributed Bragg Reflector (Distributed Bragg Reflector) with the super-surface structure, utilize the super-surface structure to regulate and control the polarization of light, determine the polarization dependence direction of the filter by the direction of the metal nano-rod of the super-surface structure, and the polarization direction of emergent light is the minor axis direction of the metal nano-rod.
Fig. 3 is a schematic structural diagram of a polarization-dependent infrared narrow-band filter according to a preferred embodiment of the present invention, where the infrared narrow-band filter includes an upper Distributed Bragg Reflector (DBR) 10 and a lower Distributed Bragg Reflector (DBR) 10, the lower DBR 10 is disposed right above, and the upper DBR 10 is stacked upside down. A defect layer 20 is provided between the two dbr 10.
Wherein each distributed bragg reflector 10 comprises a silicon substrate 11 and alternating layers of low and high refractive index dielectric materials. The dielectric material with a low refractive index is a silicon dioxide film in this embodiment, and the dielectric material with a high refractive index is a silicon film in this embodiment. Specifically, as shown in fig. 3, the dbr 10 includes a silicon substrate 11 and three stacked silicon dioxide thin films 111 and 112 grown alternately. The refractive index of the silicon dioxide film 111 in the near infrared region is about 1.46, and the refractive index of the silicon film 112 is 3.49. The silicon substrate 11 of each distributed Bragg reflector 10 is provided with 6 layers of films, the preferable thickness of each film is 290nm, and the growing and superposing sequence is a silicon dioxide film 111, a silicon film 112, a silicon dioxide film 111 and a silicon film 112 from bottom to top. Thus, the top surface of the monolithic DBR 10 is the silicon membrane 112. The silicon oxide thin film 111 and the silicon thin film 112 can be formed by a vapor deposition method.
As shown in fig. 3, the defect layer 20 includes a metal nano-array super-surface structure 21 and a transparent polymer material 22 encapsulated in the metal nano-rod array super-surface structure 21. In the present invention, the metal nanorod array super-surface structure 21 specifically uses gold nanorods 211 as the smallest repeating unit, and the gold nanorods are arrayed according to a certain period to form a gold nanorod array.
The method for manufacturing the defect layer 20 comprises the following steps: firstly, a gold nanorod array is formed on the surface of the silicon thin film 112 of one distributed bragg reflector 10, then, the surface and the periphery of the gold nanorod array are filled with a soft PMMA material in a coating mode, and the transparent polymer material 22 is formed by the PMMA material after curing treatment. After the defect layer 20 is formed, the other piece of dbr 10 is turned upside down on the transparent polymer material 22 by contacting the silicon thin film 112 on the top surface with the upper surface of the transparent polymer material 22. Thus, the polarization dependent infrared narrow band filter of the preferred embodiment of the present invention is formed. Wherein, the mode of forming the gold nanorod array can be as follows: coating electron beam glue on the surface of a piece of distributed Bragg reflector (10), writing a preset structure by adopting an electron beam, and carrying out development operation, wherein the preset structure comprises an array consisting of a plurality of rod-shaped (graph with long and short axes), then evaporating gold (such as 200 nm) with a certain thickness, and after evaporation, stripping the electron beam glue (by adopting a glue removing liquid) and washing (by using acetone), thus obtaining the gold-rice-stick array.
In the present embodiment, the transparent polymer material 22 is PMMA. Preferably, PMMA has a refractive index in the near infrared spectrum of 1.48, with a negligible absorption coefficient (absorption loss). The PMMA transmittance can reach more than 92 percent, the glass transition temperature is low, the water absorption and expansion coefficient are low, the size and the shape are stable, and the like. The lower glass transition temperature can avoid the influence on the metal nanorod array when the metal nanorod array is encapsulated and coated. In the defect layer 20, the length of the single gold nanorod 211 of the metal nanorod array super-surface structure 21 is 220-300nm, the width is 80nm, the thickness is 200nm, and the array period is 640nm. The thickness of the transparent polymer material 22 is 550-900nm, and the thickness of the transparent polymer material 22 is the thickness of the defect layer 20. The thickness of defect layer 20 determines the peak position of the filtering.
As shown in fig. 5, it is a filtered spectrum (a) in the x polarization direction and a filtered spectrum (b) in the y polarization direction when the length of a single gold nanorod in the gold nano array is 220 nm. Through measurement and calculation, when the size of the gold nanorods 211 in the defect layer 20 is 220nm long, 80nm wide, 200nm thick, and 640nm in period, and the thickness of the transparent polymer material 22 (i.e. the thickness of the defect layer 20) is changed within the range of 550-700nm (the thickness of the gold nanorods 211 is unchanged, and the thickness of PMMA is changed), when a broadband light source of 1300-1500nm is normally incident to the narrow band filter of the structure shown in fig. 3, the transmitted light is mainly a narrow band spectrum of gradual red shift along the minor axis direction of the gold nanorods in the light source range, the thickness of the defect layer 20 in the figure is increased by 30nm as an interval, the peak position is gradually red shift between 1300-1500nm, and only the light parallel to the minor axis direction of the gold nanorods 211 can be transmitted, the transmittance can reach 80%, and the half-wave width is 8nm; the light transmission in the direction perpendicular to the short axis of the gold nanorods 211 is less than 8%, and almost no light transmission is possible; thereby achieving a polarization dependent narrow band filtering effect.
As shown in fig. 6, the filtered spectrum (a) in the x-polarization direction and the filtered spectrum (b) in the y-polarization direction are obtained when the length of each gold nanorod in the gold nano array is 300 nm. When the size of the gold nanorods 211 in the defect layer 20 is 300nm long, 80nm wide, 200nm thick, and 640nm period, and the thickness of the transparent polymer material 22 (i.e. the thickness of the defect layer 20) is changed in the range of 550-700nm (the thickness of the gold nanorods 211 is not changed, and the thickness of PMMA is changed), when a broadband light source of 1400-1650nm is normally incident to the narrowband filter of the structure shown in fig. 3, the transmitted light is mainly a narrowband spectrum of gradual red shift along the minor axis direction of the gold nanorods in the light source range, the thickness of the defect layer 20 in the figure is increased by 30nm as an interval, the peak position is gradually red shift between 1400-1650nm, and only the light parallel to the minor axis direction of the gold nanorods can be transmitted, the transmittance can reach 80%, and the half-wave width is 8nm; the light transmission in the direction perpendicular to the short axis of the gold nanorod is less than 8%, and the light is hardly transmitted. Thereby achieving a polarization dependent narrow band filtering effect.
It should be noted that fig. 5-fig. 6 are diagrams illustrating effects of obtaining a narrow-band filter by using a numerical computation (FDTD) method, and obtaining a wave characteristic of an electromagnetic wave by solving maxwell equations in different material systems. The properties of the materials involved therein influence the calculation results. The refractive index and absorption coefficient of the gold nanorod material used in the numerical calculation process are shown in fig. 4. The other materials related in the invention are mainly dielectric materials, and almost have no absorption in the range of 1300-1650 nm; the refractive indices of silicon, silicon dioxide, and PMMA are 3.49,1.46, and 1.48, respectively.
In summary, the technical effects brought by the polarization-dependent infrared narrow-band filter of the embodiment include: narrow-band filtering with narrow band (half-wave width less than 8 nm) near 1550nm and high transmission (more than 80%) is realized; polarization dependent narrow-band filtering is achieved; the gold nanorods 211 are polarized and transmitted along the short axis direction, and are not transmitted along the long axis direction.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. A polarization dependent narrow infrared band filter, comprising:
the optical device comprises two distributed Bragg reflectors and a defect layer positioned between the two distributed Bragg reflectors; the defect layer comprises a metal nanorod array and a transparent high polymer material coated around and on the metal nanorod array; the thickness of the defect layer is adjustable; the polarization direction of the filtering wave of the infrared narrow-band filter is determined by the direction of the metal nano-rods in the defect layer, and the peak position is determined by the thickness of the defect layer.
2. The polarization-dependent infrared narrow band filter according to claim 1, wherein the distributed bragg reflectors respectively comprise a silicon wafer substrate, and a silicon dioxide thin film and a silicon thin film alternately grown on the silicon wafer substrate.
3. The polarization-dependent infrared narrow band filter according to claim 2, wherein three layers of silicon dioxide thin films and silicon thin films, six layers of thin films in total, are alternately grown on the silicon wafer substrate.
4. The polarization-dependent infrared narrow-band filter according to any one of claims 1 to 3, wherein the metal nanorod array is an array consisting of gold nanorods.
5. A polarization dependent infrared narrow band filter according to claim 1, wherein the transparent polymer material is PMMA, AS, transparent ABS, PC or PS.
6. The polarization-dependent infrared narrow band filter of claim 1, wherein the transparent polymeric material is PMMA.
7. The polarization-dependent infrared narrow band filter according to claim 2, wherein the two pieces of distributed bragg reflectors have two identical structures, wherein the refractive index of the silicon dioxide thin film is 1.46, and the refractive index of the silicon thin film is 3.49; the thickness of each layer of film is 240 to 320nm.
8. The polarization-dependent infrared narrowband filter according to claim 4, characterized in that the gold nanorods have dimensions of 220-300nm in length, 80nm in width and 200nm in thickness; the period of the array formed by the gold nanorods is 640nm; the thickness of the defect layer is 550-900nm.
9. A method for preparing a polarization dependent infrared narrow band filter according to any one of claims 1 to 8, comprising:
s1, preparing two distributed Bragg reflectors;
s2, forming a metal nanorod array on the surface of one of the distributed Bragg reflectors;
s3, filling softened transparent high polymer materials around and on the metal nanorod array, and curing after filling;
and S4, inverting the other distributed Bragg reflector on the transparent high polymer material.
10. The method of claim 9, wherein in S2, the metal nanorod array is formed in a manner that: firstly, coating photoresist on the surface of the distributed Bragg reflector, writing a preset structure by adopting photoetching, and carrying out development operation; the preset structure comprises an array consisting of a plurality of rod-shaped graphic units, metal materials are evaporated, and photoresist is stripped and washed after evaporation, namely a super-surface structure consisting of the metal nanorod arrays is formed on the surface of the distributed Bragg reflector.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106324940A (en) * | 2016-09-19 | 2017-01-11 | 国家纳米科学中心 | All-optical modulator aiming at circularly polarized light and manufacturing method thereof |
| CN110146949A (en) * | 2019-05-29 | 2019-08-20 | 西北工业大学深圳研究院 | A kind of narrow-band spectrum filter structure and preparation method thereof |
| CN110568526A (en) * | 2019-08-08 | 2019-12-13 | 武汉大学 | Color printing device and method based on metal nano brick array |
| CN110632692A (en) * | 2019-11-07 | 2019-12-31 | 南方科技大学 | Filter, preparation method thereof and spectrum detection system |
| CN110783351A (en) * | 2018-07-30 | 2020-02-11 | 台湾积体电路制造股份有限公司 | Narrow band filter with high transmittance |
| CN111811648A (en) * | 2020-07-21 | 2020-10-23 | 京东方科技集团股份有限公司 | Spectrometer and preparation method thereof |
-
2021
- 2021-08-10 CN CN202110911439.XA patent/CN113568101B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106324940A (en) * | 2016-09-19 | 2017-01-11 | 国家纳米科学中心 | All-optical modulator aiming at circularly polarized light and manufacturing method thereof |
| CN110783351A (en) * | 2018-07-30 | 2020-02-11 | 台湾积体电路制造股份有限公司 | Narrow band filter with high transmittance |
| CN110146949A (en) * | 2019-05-29 | 2019-08-20 | 西北工业大学深圳研究院 | A kind of narrow-band spectrum filter structure and preparation method thereof |
| CN110568526A (en) * | 2019-08-08 | 2019-12-13 | 武汉大学 | Color printing device and method based on metal nano brick array |
| CN110632692A (en) * | 2019-11-07 | 2019-12-31 | 南方科技大学 | Filter, preparation method thereof and spectrum detection system |
| CN111811648A (en) * | 2020-07-21 | 2020-10-23 | 京东方科技集团股份有限公司 | Spectrometer and preparation method thereof |
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