CN217879694U

CN217879694U - Photonic crystal film for filtering infrared rays and reducing radiant heat

Info

Publication number: CN217879694U
Application number: CN202222393062.6U
Authority: CN
Inventors: 桂之翌
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-09-07
Filing date: 2022-09-07
Publication date: 2022-11-22
Anticipated expiration: 2032-09-07

Abstract

The embodiment of the utility model discloses a photonic crystal film for filtering infrared rays and reducing radiant heat, which comprises at least one filter layer, wherein the filter layer comprises a plurality of sub-crystal areas A and a plurality of sub-crystal areas B, and the sub-crystal areas A and the sub-crystal areas B are arranged at intervals and are criss-cross to form a grid shape; the sub-crystal A area comprises a plurality of A unit groups which are arranged in an overlapping mode, and the A unit groups comprise a first PMMA layer and a first PEI layer which are arranged in an overlapping mode; the sub-crystal B region comprises a plurality of B unit groups which are arranged in an overlapped mode, and the B unit groups comprise a second PMMA layer and a second PEI layer which are arranged in an overlapped mode; the thickness of the first PMMA layer is 0.4-0.7 μm, the thickness of the second PMMA layer is 1.7-2.1 μm, the thickness of the first PEI layer is 0.3-0.6 μm, and the thickness of the second PEI layer is 1.5-2.0 μm. The utility model provides a photonic crystal film can filter the infrared ray of different wavelengths to reduce its radiant heat.

Description

Photonic crystal film for filtering infrared rays and reducing radiant heat

Technical Field

The utility model relates to a photonic crystal membrane technical field especially relates to a photonic crystal film for filtering infrared ray reduces radiant heat.

Background

High temperature in summer in various big cities is continuously affecting people's daily life due to the aggravation of global warming and the heat island effect caused by the rapid development of cities. Wherein, the influence on the majority of car owners is more obvious. When the automobile is driven or parked in an open environment, a large-area windshield faces the sun with a straight hot fire in summer, so that a large amount of sunlight directly enters the interior of the automobile cabin through glass with extremely low filtering property, and infrared rays with longer wavelength are generated by reflection of various surfaces in the city, and a large amount of energy enters the automobile cabin through the waves and is accumulated to become a head cause of high temperature in the automobile. It has been found that the cabin temperature of a car parked in an open air environment can surge to 46.7 ℃ in an hour, whereas the surface temperature of a car seat with a lower specific heat capacity can be as high as approximately 90 ℃. Therefore, the control of high temperature in the vehicle is an urgent problem to be solved.

Through studies, we found that the main sources of high vehicle cabin temperatures are Infrared (IR) with wavelengths of 0.75-5.5 μm and 7.5-15 μm. Therefore, in order to reduce the increase of heat in the vehicle, it is necessary to construct a "wavelength filter", in particular, to filter out the infrared rays in this wavelength band, which can filter out a part of all the propagating waves, and this filtered-out interval is called a photon forbidden band (Photonic band gap). To achieve this effect, we can resort to the common one of optical tools — Photonic crystals (Photonic crystals). The photonic crystal is a crystal structure formed by periodically arranging dielectric materials with different refractive indexes in space, and the material can block photons with specific frequency due to the photonic band gap, so that the movement of the photons is influenced. This effect is similar to the effect of a semiconductor crystal on the behavior of electrons. Common photonic crystals can be classified by their guiding dimensions into 1d,2d and 3D.

Optical materials can be used to filter infrared light, and common optical materials are silica, titania, optical polymers, and the like. PMMA (polymethyl methacrylate) has the advantage of high transparency as a high-molecular polymer, has higher light transmittance than glass, and is a product with the highest light transmittance in a high-molecular transparent material. The optical-grade PMMA has better optical performance, and also has the advantages of high strength, high toughness, insulation, heat resistance, weather resistance, easy processing and the like. Polyetherimides (PEI) are excellent coating and film-forming materials capable of forming coatings and films suitable for the electronics industry.

SUMMERY OF THE UTILITY MODEL

Based on the above problem, the present invention provides a photonic crystal film for filtering infrared radiation and reducing radiant heat, which has a considerable photon forbidden band between two regions of 0.75-5.5 μm and 7.5-15 μm, respectively, and can filter infrared rays between different regions, thereby reducing radiant heat thereof.

The technical scheme of the utility model is that:

a photonic crystal film for filtering infrared rays and reducing radiant heat comprises at least one filter layer, wherein the filter layer comprises a plurality of sub-crystal areas A and a plurality of sub-crystal areas B, and the sub-crystal areas A and the sub-crystal areas B are arranged at intervals and are criss-cross to form a grid shape; the sub-crystal A area comprises a plurality of A unit groups which are arranged in an overlapping mode, and the A unit groups comprise a first PMMA layer and a first PEI layer which are arranged in an overlapping mode; the sub-crystal B region comprises a plurality of B unit groups which are arranged in an overlapped mode, and the B unit groups comprise a second PMMA layer and a second PEI layer which are arranged in an overlapped mode; the thickness of the first PMMA layer is 0.4-0.7 mu m, the thickness of the second PMMA layer is 1.7-2.1 mu m, the thickness of the first PEI layer is 0.3-0.6 mu m, and the thickness of the second PEI layer is 1.5-2.0 mu m.

In some embodiments, the sub-crystalline a region comprises 20 to 30 overlapping sets of a elements.

In some embodiments, the sub-crystalline B region comprises 20 to 30B cell groups arranged in an overlapping arrangement.

In some embodiments, the thickness of the first PEI layer is less than the thickness of the first PMMA layer and the thickness of the second PEI layer is less than the thickness of the second PMMA layer.

In some embodiments, the first PMMA layer is 0.5 to 0.6 μm thick and the first PEI layer is 0.4 to 0.5 μm thick.

Preferably, the thickness of the first PMMA layer is 0.52822 μm and the thickness of the first PEI layer is 0.48026 μm.

In some embodiments, the thickness of the second PMMA layer is 1.8 to 2.0 μm and the thickness of the second PEI layer is 1.7 to 1.9 μm.

Preferably, the thickness of the second PMMA layer is 1.92543 μm, and the thickness of the second PEI layer is 1.75063 μm.

Preferably, the sub-crystal A area comprises 25A unit groups which are arranged in an overlapping mode, the thickness of the first PMMA layer is 0.52822 mu m, and the thickness of the first PEI layer is 0.48026 mu m; the sub-crystal B area comprises 25B unit groups which are arranged in an overlapping mode, the thickness of the second PMMA layer is 1.92543 mu m, and the thickness of the second PEI layer is 1.75063 mu m.

In some embodiments, the photonic crystal film comprises a plurality of filter layers arranged in an overlapping manner.

The utility model has the advantages that:

the photonic crystal film of the utility model has considerable photonic forbidden bands in the two intervals of 0.75-5.5 and 7.5-15 μm respectively. Because the two photon forbidden zones are separated greatly, two different photonic crystal sub-crystal A and sub-crystal B designs are adopted to respectively filter infrared rays in one zone, the sub-crystal A and the sub-crystal B are arranged at intervals and in a staggered mode to achieve the effect of mutual complementation, and finally the infrared rays with the wavelengths of 0.75-5.5 micrometers and 7.5-15 micrometers are filtered, so that the radiant heat is reduced, and the photonic crystal sub-crystal A and the sub-crystal B can be used for preventing high temperature in a vehicle on the glass of the vehicle window and preventing high temperature in a room on the building window.

The utility model discloses a photonic crystal film has:

1) Ductility: the material is soft, has good ductility, can be folded and spread, and is easy to be attached to window glass or building window glass; optical polymers PMMA (polymethyl methacrylate) and PEI (polyetherimide) are screened from various optical materials and used for manufacturing the photonic crystal film, compared with the traditional optical materials such as silicon dioxide or titanium dioxide, the prepared photonic crystal film has better ductility and is more suitable for being applied to glass;

2) Light and thin property: the photonic crystal film of the utility model is light and thin, easy to be attached and installed and not easy to drop;

3) Visibility: the transparent material is adopted, so that the prepared photonic crystal film influences the transmission of visible light as little as possible, the average transmission percentage reaches relevant regulations, and the photonic crystal film is applied to vehicle windows, does not influence the observation of the road condition in front when driving, and meets the requirement of the visibility of vehicle windows and windshields.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the description below are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Wherein:

fig. 1 is a schematic structural diagram of the photonic crystal thin film of the present invention.

Fig. 2 is a right side view of fig. 1.

Description of reference numerals:

1. filter layer

2. Zone A of the subgrain

21 A unit group

211. A first PMMA layer

212. A first PEI layer

3. Zone of sub-crystal B

31 B unit group

311. A second PMMA layer

312. Second PEI layer

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Example 1

The utility model provides a photonic crystal film for filtering infrared ray and reducing radiant heat, as shown in figure 1-2, comprises at least one filter layer 1, wherein the filter layer 1 comprises a plurality of sub-crystal A areas 2 and a plurality of sub-crystal B areas 3, and the sub-crystal A areas 2 and the sub-crystal B areas 3 are arranged at intervals and are criss-cross to form a grid shape; the sub-crystal A area 2 comprises a plurality of A unit groups 21 which are arranged in an overlapping mode, the A unit groups 21 comprise a first PMMA layer 211 and a first PEI layer 212 which are arranged in an overlapping mode; the sub-crystal B region 3 comprises a plurality of B unit groups 31 which are arranged in an overlapping mode, and the B unit groups 31 comprise a second PMMA layer 311 and a second PEI layer 312 which are arranged in an overlapping mode; the thickness of the first PMMA layer 211 is 0.4-0.7 μm, the thickness of the second PMMA layer 311 is 1.7-2.1 μm, the thickness of the first PEI layer 212 is 0.3-0.6 μm, and the thickness of the second PEI layer 312 is 1.5-2.0 μm.

In some embodiments, the sub-crystalline a region 2 includes 20 to 30 a cell groups 21 arranged in an overlapping arrangement.

In some embodiments, the sub-crystalline B region 3 includes 20-30B cell groups 31 arranged in an overlapping arrangement.

In some embodiments, the thickness of the first PEI layer 212 is less than the thickness of the first PMMA layer 211 and the thickness of the second PEI layer 312 is less than the thickness of the second PMMA layer 311.

In some embodiments, the thickness of the first PMMA layer 211 is between 0.5 and 0.6 μm and the thickness of the first PEI layer 212 is between 0.4 and 0.5 μm.

In some embodiments, the first PMMA layer 211 has a thickness of 0.52822 μm and the first PEI layer 212 has a thickness of 0.48026 μm.

In some embodiments, the thickness of the second PMMA layer 311 is between 1.8 and 2.0 μm and the thickness of the second PEI layer 312 is between 1.7 and 1.9 μm.

In some embodiments, the thickness of the second PMMA layer 311 is 1.92543 μm and the thickness of the second PEI layer 312 is 1.75063 μm.

In some embodiments, the sub-crystalline a-zone 2 comprises 25 a cell groups 21 arranged one above the other, the first PMMA layer 211 has a thickness of 0.52822 μm, the first PEI layer 212 has a thickness of 0.48026 μm; the subgrain B zone 3 comprises 25 groups 31 of B units arranged in an overlapping manner, the thickness of the second PMMA layer 311 is 1.92543 μm, and the thickness of the second PEI layer 312 is 1.75063 μm. At this time, when the number of layers of the filter layer 1 is one, the obtained photonic crystal film can achieve the object of filtering out 80% or more of infrared rays having wavelengths of 0.75 to 5.5 μm and 7.5 to 15 μm, thereby reducing radiant heat.

In some embodiments, the photonic crystal film of the present invention includes a plurality of filter layers 1 stacked one on top of the other. The multilayer filter layer 1 can be selected to be compounded together to obtain the photonic crystal film according to the requirement, so that a better infrared filtering effect is achieved.

The photonic crystal film of the utility model is a 'wavelength filter' designed and obtained by using 1D photonic crystal as a basic model, and has considerable photon forbidden bands respectively between the two intervals of 0.75-5.5 mu m and 7.5-15 mu m. The A unit group forming the subgrain A area and the B unit group forming the subgrain B area are formed by overlapping PMMA layers and PEI layers with different thicknesses, the refractive indexes of the two materials PMMA and PEI are different, the refractive index of PMMA is 1.4672, and the refractive index of PEI is 1.6137.

Experiments confirm that when the thickness of the first PMMA layer is set to be 0.53 mu m, the thickness of the first PEI layer is set to be 0.48 mu m, the thickness of the second PMMA layer is set to be 1.93 mu m, and the thickness of the second PEI layer is set to be 1.75 mu m, the sub-crystal A region is provided with 25A unit groups, the sub-crystal B region is provided with 25B unit groups, the number of filter layers is one, at the moment, the central wavelength of the photon forbidden region of the sub-crystal A region is 3.1 mu m, the central wavelength of the photon forbidden region of the sub-crystal B region is 11.3 mu m, the prepared photonic crystal film is attached to the vehicle window glass, so that more than 80% of infrared rays with the wavelengths of 0.75-5.5 mu m and 7.5-15 mu m can be filtered, the average transmission rate of the sub-crystal A region in a visible light region of 400-800nm is 92.33%, the average transmission rate of the sub-crystal B region in a visible light region of 400-800nm is 98.06%, the transmission rate of the vehicle window glass is high, and the normal driving is not influenced when the vehicle window glass is applied.

The utility model discloses a photonic crystal film adopts sol-gel spin coating deposition technique to prepare, preparation PMMA and PEI solution, and the heating makes its state that reaches colloidal solution, and spin coating deposit PMMA and PEI sol on soda-lime glass substrate obtain PMMA and PEI micron layer, and the thickness adjustment on PMMA and PEI layer that membrane deposition rate, annealing temperature and originated sol are according to the preparation.

There are many reported techniques for preparing micro-nano multilayer films, for example, the micro-nano multilayer coextrusion technique can easily obtain films and sheets with tens of layers to thousands of layers, and the number and thickness of the layers can be controlled by controlling the number of layering units; the laser direct writing technology is also reported to be used for preparing micro-nano films, and the like; the photonic crystal film of the present invention can also be prepared by these mature techniques.

The utility model discloses a photonic crystal film has compromise the performance and the cost of product, from factors such as optical material's refracting index, light transmissivity, anti ultraviolet nature, colour, density, unit cost, selects PMMA, PEI as the optical material of preparation photonic crystal film. Because the target photon forbidden zone is positioned in two wavelength bands which are far away from each other, two different photonic crystals (a sub-crystal A zone and a sub-crystal B zone) are arranged at intervals, so that complementary effects are achieved, and the targets of filtering infrared rays with target wavelengths of 0.75-5.5 microns and 7.5-15 microns are finally achieved, so that the radiant heat of the target photons is effectively reduced. Meanwhile, the product has good ductility and visibility, and has light thinness:

1) Ductility: the material is soft, has good ductility, can be folded and spread, and is easy to be attached to window glass or building window glass; the photonic crystal film of the present invention is prepared by screening optical polymers PMMA (polymethyl methacrylate) and PEI (polyetherimide) from various optical materials, and compared with the conventional optical materials such as silica or titania, the prepared photonic crystal film has better ductility and is more suitable for being applied on glass;

3) Visibility: the transparent material is adopted, so that the prepared photonic crystal film influences the transmission of visible light as little as possible, the average transmission percentage reaches relevant regulations, and the photonic crystal film is applied to a vehicle window without influencing the observation of the front road condition during driving, so that the requirement on the visibility of the vehicle window windshield is met.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the invention, which is defined by the appended claims.

Claims

1. A photonic crystal film for filtering infrared rays to reduce radiant heat, comprising: the optical filter comprises at least one optical filter layer, wherein the optical filter layer comprises a plurality of sub-crystal areas A and a plurality of sub-crystal areas B, and the sub-crystal areas A and the sub-crystal areas B are arranged at intervals and are crisscrossed to form a grid shape; the sub-crystal A area comprises a plurality of A unit groups which are arranged in an overlapping mode, and the A unit groups comprise a first PMMA layer and a first PEI layer which are arranged in an overlapping mode; the sub-crystal B region comprises a plurality of B unit groups which are arranged in an overlapped mode, and the B unit groups comprise a second PMMA layer and a second PEI layer which are arranged in an overlapped mode; the thickness of the first PMMA layer is 0.4-0.7 mu m, the thickness of the second PMMA layer is 1.7-2.1 mu m, the thickness of the first PEI layer is 0.3-0.6 mu m, and the thickness of the second PEI layer is 1.5-2.0 mu m.

2. The photonic crystal thin film of claim 1, wherein: the sub-crystal A area comprises 20-30A unit groups which are arranged in an overlapping mode.

3. The photonic crystal thin film of claim 1, wherein: the sub-crystal B area comprises 20-30B unit groups which are arranged in an overlapping mode.

4. The photonic crystal thin film of claim 1, wherein: the thickness of the first PEI layer is less than the thickness of the first PMMA layer, and the thickness of the second PEI layer is less than the thickness of the second PMMA layer.

5. The photonic crystal thin film of claim 1, wherein: the thickness of the first PMMA layer is 0.5-0.6 μm, and the thickness of the first PEI layer is 0.4-0.5 μm.

6. The photonic crystal film according to claim 5, wherein: the thickness of the first PMMA layer is 0.52822 μm, and the thickness of the first PEI layer is 0.48026 μm.

7. The photonic crystal thin film of claim 1, wherein: the thickness of the second PMMA layer is 1.8-2.0 μm, and the thickness of the second PEI layer is 1.7-1.9 μm.

8. The photonic crystal thin film of claim 7, wherein: the thickness of the second PMMA layer is 1.92543 μm, and the thickness of the second PEI layer is 1.75063 μm.

9. The photonic crystal film according to claim 1, wherein: the sub-crystal A area comprises 25A unit groups which are arranged in an overlapping mode, the thickness of the first PMMA layer is 0.52822 mu m, and the thickness of the first PEI layer is 0.48026 mu m; the sub-crystal B area comprises 25B unit groups which are arranged in an overlapping mode, the thickness of the second PMMA layer is 1.92543 mu m, and the thickness of the second PEI layer is 1.75063 mu m.

10. The photonic crystal thin film of claim 1, wherein: comprises a plurality of filter layers which are arranged in an overlapping way.