Chalcogenide glass dual-band antireflection film and preparation method thereof

Abstract

The application belongs to the technical field of infrared coating and discloses a chalcogenide glass double-waveband antireflection film, which comprises film system structures symmetrically arranged on two sides of a chalcogenide glass substrate, wherein the film system structures are sequentially arranged from the inside to the outside of the chalcogenide glass substrate as a first Y2O3 layer, a second YbF3 layer, a third ZnSe layer, a fourth YbF3 layer, a fifth ZnSe layer, a sixth YbF3 layer, a seventh Y2O3 layer, an eighth YbF3 layer, a ninth ZnSe layer, a tenth YbF3 layer and an eleventh ZnSe layer. The film system structures arranged on the chalcogenide glass substrate can improve the transmittance of optical lenses in specific wavebands (1.064 μm waveband and 7.7-10.5 μm waveband), thereby meeting market demands.

Description

Technical Field

[0001] This invention belongs to the field of infrared coating technology, specifically relating to the preparation of antireflection films, and more particularly to a chalcogenide glass dual-band antireflection film and its preparation method. Background Technology

[0002] Chalcogenide glasses have wide applications in the fields of infrared optics and laser technology. Due to their excellent infrared transmittance and tunability, they are widely used in infrared optical systems, laser technology and optical communication networks.

[0003] However, chalcogenide glasses have limited transmission performance in the 1.064μm and 7.7μm-10.5μm bands, and traditional single-band antireflective films generally have poor transmission performance in the 1.064μm and 7.7μm-10.5μm bands, which can no longer meet market demands. Summary of the Invention

[0004] In view of the defects and deficiencies of the existing technology, the present invention provides a chalcogenide glass dual-band antireflection film in the first aspect; and a method for preparing the above-mentioned chalcogenide glass dual-band antireflection film.

[0005] To achieve the above objectives, the present invention provides the following technical solutions.

[0006] In a first aspect, the present invention provides a dual-band antireflection film for chalcogenide glass, comprising a film structure symmetrically disposed on both sides of a chalcogenide glass substrate, wherein the film structure comprises, from the inner side to the outer side of the chalcogenide glass substrate, a first Y2O3 layer, a second YbF3 layer, a third ZnSe layer, a fourth YbF3 layer, a fifth ZnSe layer, a sixth YbF3 layer, a seventh Y2O3 layer, an eighth YbF3 layer, a ninth ZnSe layer, a tenth YbF3 layer, and an eleventh ZnSe layer.

[0007] Preferably, the thickness of the first Y₂O₃ layer is 15 nm; the thickness of the second YbF₃ layer is 66.23 nm; the thickness of the third ZnSe layer is 48.33 nm; the thickness of the fourth YbF₃ layer is 80.22 nm; the thickness of the fifth ZnSe layer is 608.36 nm; the thickness of the sixth YbF₃ layer is 800 nm; the thickness of the seventh Y₂O₃ layer is 15 nm; the thickness of the eighth YbF₃ layer is 421.54 nm; the thickness of the ninth ZnSe layer is 31.95 nm; the thickness of the tenth YbF₃ layer is 156.81 nm; and the thickness of the eleventh ZnSe layer is 26.11 nm.

[0008] Secondly, the present invention provides a method for preparing the above-mentioned chalcogenide glass dual-band antireflection film, comprising the following steps:

[0009] Step 1: Cleaning the surface of the chalcogenide glass substrate and adding the film material;

[0010] Step 2: Heat and bake the chalcogenide glass substrate under vacuum conditions to pre-melt the film material;

[0011] Step 3: Ion cleaning of the chalcogenide glass substrate;

[0012] Step 4: The substrate is sequentially deposited with the first Y2O3 layer, the second YbF3 layer, the third ZnSe layer, the fourth YbF3 layer, the fifth ZnSe layer, the sixth YbF3 layer, the seventh Y2O3 layer, the eighth YbF3 layer, the ninth ZnSe layer, the tenth YbF3 layer, and the eleventh ZnSe layer under a vacuum atmosphere;

[0013] Step 5: Cool and remove the part;

[0014] Step six: Repeat steps one through five above to deposit a film structure on the other side of the chalcogenide glass substrate.

[0015] Preferably, in step one, ultrasonic cleaning is used to clean the chalcogenide glass substrate.

[0016] Preferably, in step two, a gradient heating method is used to heat the food during baking, with a baking temperature of 100-160℃, a holding time of 2-45 min, and a heating rate of 2℃ / min.

[0017] Preferably, step two, the heating and baking process includes a heating stage, a heat preservation stage, and a cooling stage;

[0018] Further optimization involves a heating rate of 2℃ / min during the heating stage, followed by a heat preservation stage once the temperature reaches 100℃.

[0019] Further optimization involves the following steps during the heat preservation stage: when the temperature range is 100~160℃, heat preservation is performed for 5 minutes for every 10℃ increase; when the temperature reaches 170℃, heat preservation is performed for 45 minutes; when the temperature reaches 180℃, heat preservation is performed for 30 minutes; and when the temperature reaches 190℃, heat preservation is performed for 2 minutes before entering the cooling stage.

[0020] Further optimization involves the following steps during the cooling phase: when the temperature is between 130 and 180°C, the temperature is maintained at 10°C for 6 minutes; the system temperature is then maintained at 130°C before proceeding to step four.

[0021] Preferably, in step two, the vacuum degree is 3.0 × 10⁻⁶ when pre-melting the film material. -3 ~5.0×10 -3 Pa.

[0022] Preferably, in step three, the vacuum level is 1.0 × 10⁻⁶ when cleaning the chalcogenide glass substrate. -3 ~2.0×10 -3Pa; cleaning time is 200-400s; Hall ion source parameters are: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 220V, anode current 2A, argon flow rate 100%.

[0023] Preferably, in step four, the ZnSe layer and the YbF3 layer are deposited by resistance heating process; the Y2O3 layer is deposited by electron beam heating process.

[0024] Preferably, in step four, the evaporation rate of ZnSe is 6 Å / s; the evaporation rate of YbF3 is 5 Å / s; and the evaporation rate of Y2O3 is 2 Å / s.

[0025] Preferably, in step four, ion-assisted deposition is used when depositing the film structure.

[0026] Preferably, in step four, the ion source parameters for ion-assisted vapor deposition of ZnSe material are: neutralization current 0.5A, neutralization gas flow rate 8sccm, anode voltage 100V, anode current 1A, and argon gas flow rate 100%.

[0027] Preferably, the ion source parameters for ion-assisted evaporation of YbF3 and Y2O3 materials are: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 130V, anode current 1.3A, argon flow rate 30%, and oxygen flow rate 70%.

[0028] Preferably, in step four, the vacuum degree during coating is 4.5 × 10⁻⁶. -3 ~5.5×10 -3 Pa.

[0029] Preferably, in step four, the film thickness is controlled using a quartz crystal oscillator with a frequency of 6MHz.

[0030] Preferably, step four includes a heat preservation stage, where the film structure is heat-preserved for 30 minutes after deposition.

[0031] Compared with the prior art, the present invention has the following significant advantages:

[0032] (1) By setting a film structure on a chalcogenide glass substrate, the transmittance of optical lenses in specific wavelength bands (1.064μm band and 7.7~10.5μm band) can be improved to meet market demand.

[0033] (2) By optimizing parameters such as the evaporation rate of the film material, pre-melting and ion cleaning conditions, and vacuum control, the coating effect can be improved, thereby increasing the transmittance of the antireflective film.

[0034] (3) The preparation method provided by the present invention is simple and easy to obtain a membrane structure with high transmittance, which is conducive to promotion and marketization. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the membrane system structure obtained in Example 1 of the present invention;

[0036] Figure 2 This is a transmittance curve of the optical lens obtained in Example 1 of the present invention in the 1.064μm band;

[0037] Figure 3 This is a transmittance curve of the optical lens obtained in Example 1 of the present invention in the 7.7μm to 10.5μm wavelength range; Detailed Implementation

[0038] The present invention provides the following specific technical solutions.

[0039] In a first aspect, the present invention provides a dual-band antireflection film for chalcogenide glass, comprising a film structure symmetrically disposed on both sides of a chalcogenide glass substrate, wherein the film structure comprises, from the inner side to the outer side of the chalcogenide glass substrate, a first Y2O3 layer, a second YbF3 layer, a third ZnSe layer, a fourth YbF3 layer, a fifth ZnSe layer, a sixth YbF3 layer, a seventh Y2O3 layer, an eighth YbF3 layer, a ninth ZnSe layer, a tenth YbF3 layer, and an eleventh ZnSe layer.

[0040] In a specific embodiment of the present invention, the inventors selected YbF3, ZnSe, and Y2O3 as film materials, which possess excellent optical properties and can improve the transmittance and stability of the thin film. The inventors discovered through research that a film system structure consisting of a first Y2O3 layer, a second YbF3 layer, a third ZnSe layer, a fourth YbF3 layer, a fifth ZnSe layer, a sixth YbF3 layer, a seventh Y2O3 layer, an eighth YbF3 layer, a ninth ZnSe layer, a tenth YbF3 layer, and an eleventh ZnSe layer can further improve the transmittance of the antireflective film. Combined with a chalcogenide glass substrate, the transmittance of the optical lens in the 1.064μm band and the 7.7–10.5μm band can be further improved to meet market demands.

[0041] Preferably, the thickness of the first Y₂O₃ layer is 15 nm; the thickness of the second YbF₃ layer is 66.23 nm; the thickness of the third ZnSe layer is 48.33 nm; the thickness of the fourth YbF₃ layer is 80.22 nm; the thickness of the fifth ZnSe layer is 608.36 nm; the thickness of the sixth YbF₃ layer is 800 nm; the thickness of the seventh Y₂O₃ layer is 15 nm; the thickness of the eighth YbF₃ layer is 421.54 nm; the thickness of the ninth ZnSe layer is 31.95 nm; the thickness of the tenth YbF₃ layer is 156.81 nm; and the thickness of the eleventh ZnSe layer is 26.11 nm.

[0042] Further research by the inventors revealed that when the thickness of each film layer in the film system is as described above, the optical lens exhibits superior transmittance in the 1.064μm band and the 7.7–10.5μm band.

[0043] Secondly, the present invention provides a method for preparing the above-mentioned chalcogenide glass dual-band antireflection film, comprising the following steps:

[0044] Step 1: Cleaning the surface of the chalcogenide glass substrate and adding the film material;

[0045] Step 2: Heat and bake the chalcogenide glass substrate under vacuum conditions to pre-melt the film material;

[0046] Step 3: Ion cleaning of the chalcogenide glass substrate;

[0047] Step 4: The substrate is sequentially deposited with the first Y2O3 layer, the second YbF3 layer, the third ZnSe layer, the fourth YbF3 layer, the fifth ZnSe layer, the sixth YbF3 layer, the seventh Y2O3 layer, the eighth YbF3 layer, the ninth ZnSe layer, the tenth YbF3 layer, and the eleventh ZnSe layer under a vacuum atmosphere;

[0048] Step 5: Cool and remove the part;

[0049] Step six: Repeat steps one through five above to deposit a film structure on the other side of the chalcogenide glass substrate.

[0050] Preferably, in step one, ultrasonic cleaning is used to clean the chalcogenide glass substrate.

[0051] Impurities on the surface of the chalcogenide glass substrate are removed by ultrasonic cleaning to prevent them from affecting the coating process and the transmittance of the antireflective coating.

[0052] Preferably, in step two, a gradient heating method is used to heat the food during baking, with a baking temperature of 100–195°C, a holding time of 2–45 min, and a heating rate of 2°C / min.

[0053] Preferably, step two, the heating and baking process includes a heating stage, a heat preservation stage, and a cooling stage.

[0054] Further optimization involves a heating rate of 2℃ / min during the heating phase, followed by a heat preservation phase once the temperature reaches 100℃.

[0055] Further optimization involves the following steps during the heat preservation stage: when the temperature range is 100~160℃, heat preservation is performed for 5 minutes for every 10℃ increase; when the temperature reaches 170℃, heat preservation is performed for 45 minutes; when the temperature reaches 180℃, heat preservation is performed for 30 minutes; and when the temperature reaches 190℃, heat preservation is performed for 2 minutes before entering the cooling stage.

[0056] More preferably, during the cooling stage, when the temperature is 130~180℃, the temperature is maintained for 6 minutes for every 10℃ decrease; the system temperature is maintained at 130℃ to proceed to step four.

[0057] The inventors discovered that baking the substrate before coating can improve the optical and physical properties of lenses. Firstly, the thermal expansion coefficient of chalcogenide glass substrates is relatively high, differing from that of the coating material. This difference leads to stress during temperature changes. If this stress is not properly released, it accumulates between the coating and the substrate, affecting their adhesion. Baking eliminates this internal stress, improving the substrate's optical quality and stability. Secondly, it improves refractive index uniformity. By controlling the baking temperature and time, the refractive index of the chalcogenide glass lens can be made more uniform, ensuring the substrate's optical performance. Thirdly, the low hardness of chalcogenide glass substrates means that improper surface treatment can lead to insufficient adhesion between the coating and the substrate. Baking improves this adhesion, creating better conditions for subsequent substrate coating and enhancing the overall processing effect.

[0058] Further research by the inventors revealed that excessively rapid heating during the heating phase can lead to uneven heating of the lens. In practical applications, the power can be adjusted to increase the heating rate during the low-temperature phase of the heating phase, and the heating rate can be reduced once the temperature rises.

[0059] Preferably, in step two, the vacuum degree is 3.0 × 10⁻⁶ when pre-melting the film material. -3 ~5.0×10 -3 Pa.

[0060] In practical applications, there is no need to limit the temperature when pre-melting the film material. It is only necessary to ensure that the vacuum degree reaches the opening condition of the evaporation source to carry out the pre-melting process. In the existing technology, the pre-melting time is adjusted according to the amount of film material to be pre-melted. Generally, the pre-melting time is 15 minutes.

[0061] The inventors discovered through research that pre-melting can release the gas inside the coating material, eliminate other components in the coating material, prevent the coating material from splashing during coating, and maintain the stability of the coating.

[0062] Preferably, in step three, the vacuum level is 1.0 × 10⁻⁶ when cleaning the chalcogenide glass substrate. -3 ~2.0×10 -3 Pa; cleaning time is 200-400s; Hall ion source parameters are: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 220V, anode current 2A, argon flow rate 100%.

[0063] Using a Hall ion source to clean the microstructure of chalcogenide glass surfaces can eliminate surface oxide layers, organic matter, and other impurities, resulting in a cleaner surface. This prevents the oxide layer from affecting the transmittance of optical lenses and improves the adhesion conditions of the coating.

[0064] Preferably, in step four, the ZnSe layer and the YbF3 layer are deposited by resistance heating process; the Y2O3 layer is deposited by electron beam heating process.

[0065] Preferably, in step four, the evaporation rate of ZnSe is 6 Å / s; the evaporation rate of YbF3 is 5 Å / s; and the evaporation rate of Y2O3 is 2 Å / s.

[0066] Preferably, in step four, ion-assisted deposition is used when depositing the film structure.

[0067] The inventors discovered through research that using a Hall ion source to assist in coating can make the film layer more dense.

[0068] Preferably, in step four, the ion source parameters for ion-assisted vapor deposition of ZnSe material are: neutralization current 0.5A, neutralization gas flow rate 8sccm, anode voltage 100V, anode current 1A, and argon gas flow rate 100%.

[0069] Preferably, the ion source parameters for ion-assisted evaporation of YbF3 and Y2O3 materials are: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 130V, anode current 1.3A, argon flow rate 30%, and oxygen flow rate 70%.

[0070] Preferably, in step four, the vacuum degree during coating is 4.5 × 10⁻⁶. -3 ~5.5×10 -3 Pa.

[0071] Preferably, in step four, the film thickness is controlled using a quartz crystal oscillator with a frequency of 6MHz.

[0072] Preferably, step four is followed by a heat preservation stage, with a heat preservation temperature of 125~135℃ and a heat preservation time of 30 minutes.

[0073] Preferably, in step five, the product is allowed to cool naturally.

[0074] To make the technical problems, technical solutions and technical advantages of the present invention clearer, a detailed description will be given below with reference to specific examples. However, the scope of protection of the present invention is not limited to the following specific embodiments.

[0075] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0076] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0077] Example 1:

[0078] A method for preparing a chalcogenide glass dual-band antireflection film includes the following steps:

[0079] Step 1: Use ultrasonic cleaning to clean the substrate and chalcogenide glass substrate. Place the substrate and chalcogenide glass substrate into the tooling fixture, and then hang the tooling fixture into the cavity of the vacuum coating machine.

[0080] Step 2: Start the vacuum coating machine, evacuate and heat the chalcogenide glass substrate, raising the temperature to 100℃ at a rate of 2℃ / min. When the temperature is between 100 and 160℃, hold the temperature for 5 minutes for every 10℃ increase. When the temperature reaches 170℃, hold for 45 minutes; when it reaches 180℃, hold for 30 minutes; when it reaches 190℃, hold for 2 minutes, then begin the cooling phase. A gradient cooling method is used, first lowering from 195℃ to 180℃ and then holding for 6 minutes. During the cooling phase, when the temperature is between 130 and 180℃, hold for 6 minutes for every 10℃ decrease; maintain the cavity temperature of the vacuum coating machine at 130℃. While baking the chalcogenide glass substrate, evacuate the cavity of the vacuum coating machine, maintaining a vacuum level of 4.0 × 10⁻⁶. -3 Pa begins pre-melting the film material, with a pre-melting time of 15 minutes.

[0081] Step 3, adjust the vacuum level to 1.5 × 10⁻⁶. -3 After Pa, the Hall ion source was started to clean the chalcogenide glass substrate for 300 seconds. The parameters of the Hall ion source during cleaning were: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 220V, anode current 2A, and argon flow rate 100%.

[0082] Step 4: Maintain a constant vacuum of 5.0 × 10⁻⁶ -3 At a system temperature of 130℃, a first Y₂O₃ layer, a second YbF₃ layer, a third ZnSe layer, a fourth YbF₃ layer, a fifth ZnSe layer, a sixth YbF₃ layer, a seventh Y₂O₃ layer, an eighth YbF₃ layer, a ninth ZnSe layer, a tenth YbF₃ layer, and an eleventh ZnSe layer were sequentially deposited on one side of a chalcogenide glass substrate. The ZnSe and YbF₃ layers were deposited using a resistance heating process; the Y₂O₃ layer was deposited using an electron beam heating process.

[0083] When depositing the ZnSe layer, the evaporation rate of ZnSe is 6 Å / s, and the ion source parameters are: neutralization current 0.5 A, neutralization gas flow rate 8 sccm, anode voltage 100 V, anode current 1 A, and argon flow rate 100%.

[0084] When depositing the YbF3 layer, the evaporation rate of YbF3 was 5 Å / s; when depositing the Y2O3 layer, the evaporation rate of Y2O3 was 2 Å / s. The ion source parameters for depositing the YbF3 and Y2O3 layers were: neutralization current 0.6 A, neutralization gas flow rate 8 sccm, anode voltage 130 V, anode current 1.3 A, argon flow rate 30%, and oxygen flow rate 70%.

[0085] Step 5: After holding at 130℃ for 30 minutes, cool down at a rate of 0.5℃ / min until the temperature drops to 60℃, then remove the product.

[0086] Step six: Repeat steps one to five to deposit a film structure on the other side of the chalcogenide glass substrate to obtain the optical lens.

[0087] Example 2:

[0088] A method for preparing a chalcogenide glass dual-band antireflection film includes the following steps:

[0089] Step 1: Use ultrasonic cleaning to clean the substrate and chalcogenide glass substrate. Place the substrate and chalcogenide glass substrate into the tooling fixture, and then hang the tooling fixture into the cavity of the vacuum coating machine.

[0090] Step 2: Start the vacuum coating machine, evacuate and heat the chalcogenide glass substrate, raising the temperature to 100℃ at a rate of 2℃ / min. When the temperature is between 100 and 160℃, hold the temperature for 5 minutes for every 10℃ increase. When the temperature reaches 170℃, hold for 45 minutes; when it reaches 180℃, hold for 30 minutes; when it reaches 190℃, hold for 2 minutes, then begin the cooling phase. A gradient cooling method is used, first lowering from 195℃ to 180℃ and then holding for 6 minutes. During the cooling phase, when the temperature is between 130 and 180℃, hold for 6 minutes for every 10℃ decrease; maintain the cavity temperature of the vacuum coating machine at 130℃. Simultaneously with baking the chalcogenide glass substrate, evacuate the cavity of the vacuum coating machine, maintaining a vacuum level of 3.0 × 10⁻⁶. -3 Pa begins pre-melting the film material, with a pre-melting time of 15 minutes.

[0091] Step 3, adjust the vacuum level to 1.0 × 10⁻⁶. -3 After Pa, the Hall ion source was started to clean the chalcogenide glass substrate for 200 seconds. The parameters of the Hall ion source during cleaning were: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 220V, anode current 2A, and argon flow rate 100%.

[0092] Step 4: Maintain a constant vacuum of 4.5 × 10⁻⁶ -3 At a system temperature of 130℃, a first Y₂O₃ layer, a second YbF₃ layer, a third ZnSe layer, a fourth YbF₃ layer, a fifth ZnSe layer, a sixth YbF₃ layer, a seventh Y₂O₃ layer, an eighth YbF₃ layer, a ninth ZnSe layer, a tenth YbF₃ layer, and an eleventh ZnSe layer were sequentially deposited on one side of a chalcogenide glass substrate. The ZnSe and YbF₃ layers were deposited using a resistance heating process; the Y₂O₃ layer was deposited using an electron beam heating process.

[0093] When depositing the ZnSe layer, the evaporation rate of ZnSe is 6 Å / s, and the ion source parameters are: neutralization current 0.5 A, neutralization gas flow rate 8 sccm, anode voltage 100 V, anode current 1 A, and argon flow rate 100%.

[0094] When depositing the YbF3 layer, the evaporation rate of YbF3 was 5 Å / s; when depositing the Y2O3 layer, the evaporation rate of Y2O3 was 2 Å / s. The ion source parameters for depositing the YbF3 and Y2O3 layers were: neutralization current 0.6 A, neutralization gas flow rate 8 sccm, anode voltage 130 V, anode current 1.3 A, argon flow rate 30%, and oxygen flow rate 70%.

[0095] Step 5: After holding at 125℃ for 30 minutes, cool down at a rate of 0.5℃ / min until the temperature drops to 60℃, then remove the product.

[0096] Step six: Repeat steps one to five to deposit a film structure on the other side of the chalcogenide glass substrate to obtain the optical lens.

[0097] Example 3:

[0098] A method for preparing a chalcogenide glass dual-band antireflection film includes the following steps:

[0099] Step 1: Use ultrasonic cleaning to clean the substrate and chalcogenide glass substrate. Place the substrate and chalcogenide glass substrate into the tooling fixture, and then hang the tooling fixture into the cavity of the vacuum coating machine.

[0100] Step 2: Start the vacuum coating machine, evacuate and heat the chalcogenide glass substrate, raising the temperature to 100℃ at a rate of 2℃ / min. When the temperature is between 100 and 160℃, hold the temperature for 5 minutes for every 10℃ increase. When the temperature reaches 170℃, hold for 45 minutes; when the temperature reaches 180℃, hold for 30 minutes; when the temperature reaches 190℃, hold for 2 minutes, then begin the cooling stage. A gradient cooling method is used, first lowering from 195℃ to 180℃ and then holding for 6 minutes. During the cooling stage, when the temperature is between 130 and 180℃, hold for 6 minutes for every 10℃ decrease; maintain the cavity temperature of the vacuum coating machine at 130℃. While baking the chalcogenide glass substrate, evacuate the cavity of the vacuum coating machine, maintaining a vacuum level of 5.0 × 10⁻⁶. -3 Pa begins pre-melting the film material, with a pre-melting time of 15 minutes.

[0101] Step 3, adjust the vacuum level to 2.0 × 10⁻⁶. -3 After Pa, the Hall ion source was started to clean the chalcogenide glass substrate for 400 seconds. The parameters of the Hall ion source during cleaning were: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 220V, anode current 2A, and argon flow rate 100%.

[0102] Step 4: Maintain a constant vacuum of 5.5 × 10⁻⁶ -3 At a system temperature of 130℃, a first Y₂O₃ layer, a second YbF₃ layer, a third ZnSe layer, a fourth YbF₃ layer, a fifth ZnSe layer, a sixth YbF₃ layer, a seventh Y₂O₃ layer, an eighth YbF₃ layer, a ninth ZnSe layer, a tenth YbF₃ layer, and an eleventh ZnSe layer were sequentially deposited on one side of a chalcogenide glass substrate. The ZnSe and YbF₃ layers were deposited using a resistance heating process; the Y₂O₃ layer was deposited using an electron beam heating process.

[0103] When depositing the ZnSe layer, the evaporation rate of ZnSe is 6 Å / s, and the ion source parameters are: neutralization current 0.5 A, neutralization gas flow rate 8 sccm, anode voltage 100 V, anode current 1 A, and argon flow rate 100%.

[0104] When depositing the YbF3 layer, the evaporation rate of YbF3 was 5 Å / s; when depositing the Y2O3 layer, the evaporation rate of Y2O3 was 2 Å / s. The ion source parameters for depositing the YbF3 and Y2O3 layers were: neutralization current 0.6 A, neutralization gas flow rate 8 sccm, anode voltage 130 V, anode current 1.3 A, argon flow rate 30%, and oxygen flow rate 70%.

[0105] Step 5: After holding at 135℃ for 30 minutes, cool down at a rate of 0.5℃ / min until the temperature drops to 60℃, then remove the product.

[0106] Step six: Repeat steps one to five to deposit a film structure on the other side of the chalcogenide glass substrate to obtain the optical lens.

[0107] Comparative Example 1:

[0108] The difference from Example 1 is that the baking process in step two is not present, and the chalcogenide glass substrate is not baked before coating.

[0109] Comparative Example 2:

[0110] The difference from Example 1 is that, in step four, a first YbF3 layer, a second ZnSe layer, a third YbF3 layer, a fourth ZnSe layer, a fifth YbF3 layer, a sixth ZnSe layer, a seventh YbF3 layer, and an eighth ZnSe layer are sequentially deposited on one side of the chalcogenide glass substrate.

[0111] The optical lenses prepared in Examples 1-3 and Comparative Examples 1-2 were tested using a spectrometer. Figure 2 , Figure 3 It can be seen that the optical lens prepared in Example 1 has a transmittance of 99.3% in the 1.064μm band, an average transmittance of 98.6% in the 7.7-10.5μm band, and a peak transmittance of up to 98.76%, which can meet market demand.

[0112] The stability of the membrane structure was tested using the following methods:

[0113] Water immersion test: The optical lens is subjected to a water immersion test using tap water for 24 hours.

[0114] Adhesion test: After completing the water immersion and salt spray tests using tap water, apply 3M tape to each side of the lens by hand and pull the tape in the opposite direction to the adhesive end.

[0115] Thermal shock test: The temperature range of -40℃ to 85℃ was subjected to thermal shock for 24 hours in a high and low temperature chamber.

[0116] Constant temperature and humidity test: 48 hours at 50℃ and 95% relative humidity in a constant temperature and humidity chamber.

[0117] Salt spray test: Neutral salt spray test for 48 hours.

[0118] Low temperature test: Test at -40℃ in a low temperature chamber for 48 hours.

[0119] High temperature test: Test at 85℃ for 48 hours.

[0120] Table 1 - Stability test results of the membrane structures prepared in Examples 1-3 and Comparative Examples 1-2

[0121]

[0122] As shown in Table 1, heating and baking the chalcogenide glass substrate can improve the stability of the lens and the coating, and reduce the possibility of the coating peeling off the lens; the Y2O3 film layer can improve the bonding stability between the various film layers, and reduce the possibility of film separation and peeling off.

[0123] The above-described embodiments are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope of the present invention, based on the technical solution and concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A chalcogenide glass dual-band antireflective film, characterized in that, The invention includes a film structure symmetrically disposed on both sides of a chalcogenide glass substrate, wherein the film structure, from the inner side to the outer side of the chalcogenide glass substrate, consists of a first Y2O3 layer, a second YbF3 layer, a third ZnSe layer, a fourth YbF3 layer, a fifth ZnSe layer, a sixth YbF3 layer, a seventh Y2O3 layer, an eighth YbF3 layer, a ninth ZnSe layer, a tenth YbF3 layer, and an eleventh ZnSe layer. The thickness of the first Y₂O₃ layer is 15 nm; the thickness of the second YbF₃ layer is 66.23 nm; the thickness of the third ZnSe layer is 48.33 nm; the thickness of the fourth YbF₃ layer is 80.22 nm; the thickness of the fifth ZnSe layer is 608.36 nm; the thickness of the sixth YbF₃ layer is 800 nm; the thickness of the seventh Y₂O₃ layer is 15 nm; the thickness of the eighth YbF₃ layer is 421.54 nm; the thickness of the ninth ZnSe layer is 31.95 nm; the thickness of the tenth YbF₃ layer is 156.81 nm; and the thickness of the eleventh ZnSe layer is 26.11 nm.

2. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 1, characterized in that, Includes the following steps: Step 1: Cleaning the surface of the chalcogenide glass substrate and adding the film material; Step 2: Heat and bake the chalcogenide glass substrate under vacuum conditions to pre-melt the film material; Step 3: Ion cleaning; Step 4: The substrate is sequentially deposited with the first Y2O3 layer, the second YbF3 layer, the third ZnSe layer, the fourth YbF3 layer, the fifth ZnSe layer, the sixth YbF3 layer, the seventh Y2O3 layer, the eighth YbF3 layer, the ninth ZnSe layer, the tenth YbF3 layer, and the eleventh ZnSe layer under a vacuum atmosphere; Step 5: Cool and remove the part; Step six: Repeat steps one through five above to deposit a film structure on the other side of the chalcogenide glass substrate.

3. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 2, characterized in that, Step two includes a heating phase, a heat preservation phase, and a cooling phase during the heating and baking process. During the heating stage, the heating rate is 2℃ / min. After the temperature reaches 100℃, the heat preservation stage begins. During the heat preservation stage, when the temperature range is 100~160℃, the heat preservation time is 5 minutes for every 10℃ increase; when the temperature rises to 170℃, the heat preservation time is 45 minutes; when the temperature rises to 180℃, the heat preservation time is 30 minutes; when the temperature rises to 190℃, the heat preservation time is 2 minutes, and then the cooling stage begins. During the cooling phase, when the temperature is between 130 and 180°C, maintain the temperature for 6 minutes for every 10°C decrease; keep the system temperature at 130°C and proceed to step four.

4. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 2 or 3, characterized in that, In step two, during the pre-melting of the film material, the vacuum degree is 3.0 × 10⁻⁶. -3 ~5.0×10 -3 Pa.

5. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 2, characterized in that, In step three, the vacuum level is 1.0 × 10⁻⁶. -3 ~2.0×10 -3 Pa; cleaning time is 200-400s; Hall ion source parameters are: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 220V, anode current 2A, argon flow rate 100%.

6. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 2, characterized in that, In step four, the ZnSe and YbF3 layers are deposited using a resistance heating process; the Y2O3 layer is deposited using an electron beam heating process.

7. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 2, characterized in that, In step four, the evaporation rate of ZnSe is 6 Å / s; the evaporation rate of YbF3 is 5 Å / s; and the evaporation rate of Y2O3 is 2 Å / s.

8. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 7, characterized in that, When depositing the film structure, ion-assisted deposition is used. The ion source parameters for ion-assisted deposition of ZnSe material are: neutralization current 0.5A, neutralization gas flow rate 8sccm, anode voltage 100V, anode current 1A, and argon flow rate 100%. The ion source parameters for ion-assisted deposition of YbF3 and Y2O3 materials are: neutralization current 0.6A, neutralization gas flow rate 8sccm, anode voltage 130V, anode current 1.3A, argon flow rate 30%, and oxygen flow rate 70%.

9. The method for preparing a chalcogenide glass dual-band antireflection film as described in claim 2, characterized in that, In step four, the vacuum degree during coating is 4.5 × 10⁻⁶. -3 ~5.5×10 -3 Pa; film thickness is controlled using a quartz crystal oscillator with a frequency of 6MHz.

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