Design method and preparation method of chalcogenide glass substrate 8-12 mu m band high transmission film color controllable thin film

Abstract

This paper provides a method for designing and fabricating a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm wavelength range. The design method includes the following steps: Sa, using 550 nm as the reference wavelength for optical thin film design, and applying the film stacking formula: Sub / M0.5(L2HL)^5 0.5(KL)^5 / AIR, both sides are coated with the same film system, Sub is IRG chalcogenide glass, AIR represents air, H represents Ge, L represents ZnS, K represents YbF3, and M represents IDA; Sb, generate the film structure of Sub / IDA / ZnS / Ge / ZnS / Ge / ZnS / YbF3 / ZnS / Air through the film stack formula; Sc, the optimization target is the film color target and the transmittance target. The film color target is one or two adjacent colors of the seven colors of visible light (red, orange, yellow, green, cyan, blue, and violet). To design the film color of a certain color or two adjacent colors, the spectral reflectance peak of the design must be located at the wavelength of the corresponding color; Sd, film thickness optimization, to obtain the optimal film thickness. The optimized film structure achieves the target transmittance and the film color is controllable; Se, the optimal film thickness is input to the coating machine.

Description

Technical Field

[0001] This disclosure relates to the field of infrared optical thin film technology, and more specifically to a design and preparation method for a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12μm band. Background Technology

[0002] The 8-12μm band is a common application range for long-wave infrared technology. Lenses in this band have strong detection capabilities for low-temperature objects, making them suitable for temperature measurement and thermal imaging of low-temperature objects. They are widely used in infrared thermal imagers, infrared thermometers, infrared thermal imaging, night vision security equipment, and other fields. Secondly, long-wave infrared light can penetrate many common materials, such as smoke, haze, and plastics, and can be used to see through and detect heat sources or hidden objects within objects. However, due to varying application scenarios and customer preferences for film color, the selection of coating materials, the design of the film system, and the improvement of the specific coating process all present challenges. Summary of the Invention

[0003] In view of the problems existing in the background art, one object of this disclosure is to provide a design method and a preparation method for a high transmittance film with controllable color in the 8-12μm band on a chalcogenide glass substrate, which enables the designed and prepared chalcogenide glass substrate and the film system on both sides to achieve the required transmittance in the 8-12μm band and controllable film color.

[0004] Another objective of this disclosure is to provide a design and preparation method for a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band, which enables the designed and prepared silicon substrate, along with the film system on both sides, to meet the requirements of different application scenarios.

[0005] Therefore, a method for designing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12μm wavelength range includes the following steps:

[0006] Sa, the film system design uses 550nm as the reference wavelength for optical thin film design, and uses the film stack formula: Sub / M0.5(L2HL)^5 + 0.5(KL)^5 / AIR. Sub has the same film system deposited on both sides, where Sub is a chalcogenide glass substrate, the chalcogenide glass substrate is IRG chalcogenide glass, and AIR represents air. In the film stack formula: H represents a 1 / 4 wavelength thickness of high refractive index material Ge (germanium), L represents a 1 / 4 wavelength thickness of medium refractive index material ZnS (zinc sulfide), K represents a 1 / 4 wavelength thickness of low refractive index material YbF3 (ytterbium fluoride), and M represents a 1 / 4 wavelength thickness of the underlayer material IDA (titanium). (Prasein oxide mixture); Sb, using the input film stack formula, generates a film structure of Sub / IDA / ZnS / Ge / ZnS / Ge / ZnS / YbF3 / ZnS / Air; Sc, sets the optimization objectives, which are film color and transmittance objectives. The film color objective is one or two adjacent colors of the seven colors of visible light (red, orange, yellow, green, cyan, blue, violet). To design the film color of a particular color or two adjacent colors, the spectral reflectance peak needs to be located at the wavelength of the corresponding color.

[0007] Light color Wavelength (nm) Frequency (Hz) Center wavelength (nm) red 780-622 <![CDATA[3.8×10 14 -4.8×10 14 ]]> 660 orange 622-597 <![CDATA[4.8×10 14 -5.0×10 14 ]]> 610 yellow 597-577 <![CDATA[5.0×10 14 -5.4×10 14 ]]> 580 green 577-492 <![CDATA[5.4×10 14 -6.1×10 14 ]]> 540 green 492-470 <![CDATA[6.1×10 14 -6.4×10 14 ]]> 480 blue 470-455 <![CDATA[6.4×10 14 -6.6×10 14 ]]> 460 purple 455-380 <![CDATA[6.6×10 14 -7.9×10 14 ]]> 430

[0008] Sd: The film thickness is optimized using thin film design software to obtain the optimal film thickness. The optimized film structure achieves the target transmittance in the 8-12μm wavelength band and the film color is controllable. Se: The optimized film thickness is input into the control computer of the coating machine.

[0009] A method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band, characterized by the following steps: S1, cleaning the chalcogenide glass substrate (used as a lens) and the accompanying coating sheet before deposition, and preparing four film materials: IDA, ZnS, Ge, and YbF3. The IDA film material is commercially available Ida (Ti-Pr-Oxide) particles with a diameter of 0.7-3.5 mm, purchased from Umicore Corporation, USA, grade 0484519; S2, configuring the deposition process conditions and process documents, including deposition temperature, pre-deposition base vacuum, film thickness, vapor deposition mode of the film material, deposition rate of the film material, and ion source-assisted deposition. The usage and parameters, wherein the film thickness is based on the optimal film thickness stored in the control computer of the coating machine as described in the aforementioned design method for 8-12μm band high transmittance color controllable thin films on chalcogenide glass substrates; S3, the cleaned lens is placed into the tooling fixture, the tooling fixture with the lens is hung into the cavity of the coating machine, the door is closed, vacuum is drawn and heated; S4, the film material is pre-melted; S5, the ion source is pre-cleaned; S6, the film is deposited and monitored, and the film is deposited on the first side of the lens according to the coating process conditions and process document configuration in step S2; S7, the temperature is kept constant after the coating is completed; S8, the part is cooled and removed; S9, steps S1 to S8 are repeated to deposit the film on the second side of the lens.

[0010] The beneficial effects of this disclosure are as follows.

[0011] In the design method of the 8-12μm band high transmittance color controllable thin film on a chalcogenide glass substrate according to this disclosure, IDA is used as the bottom layer and as the connecting layer between the chalcogenide glass substrate and the ZnS film layer, which enhances the bonding force between the chalcogenide glass substrate and the film layer. Ge is used as a high refractive index material, YbF3 as a low refractive index material, and ZnS as a medium refractive index material, which is also used as the outermost protective layer. Thus, not only can the transmittance of the designed film structure in the 8-12μm band meet the requirements, but also the bonding between the bottom layer and the silicon substrate in the film system on both sides, as well as the water immersion test, salt spray test, adhesion test, moderate friction test, constant temperature and humidity test, low temperature test and high temperature test in the testing process of the film system on both sides, can meet the requirements of different application scenarios.

[0012] In the method for preparing a high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate according to this disclosure, based on steps S1 to S9 and the optimal film thickness stored in the control computer of the coating machine as described in the aforementioned design method for a high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate, as verified by testing, the prepared chalcogenide glass substrate, together with the film system on both sides, can achieve the required transmittance in the 8-12 μm band. Simultaneously, it can meet the requirements of water immersion tests, salt spray tests, adhesion tests, moderate friction tests, constant temperature and humidity tests, low temperature tests, and high temperature tests, thereby satisfying the requirements of different application scenarios. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the film structure of the high-transmittance, color-controllable thin film with 8-12μm wavelength on a chalcogenide glass substrate, based on the design and preparation method of the disclosed method.

[0014] Figure 2 The transmittance curve is designed using the design method of the 8-12μm band high transmittance film color controllable thin film on the chalcogenide glass substrate in Example 1.

[0015] Figure 3 This is a transmittance curve of the coating film and the film system on both sides of the substrate after the preparation method of the high transmittance film with color controllable 8-12μm band on the chalcogenide glass substrate in Example 1 is shown.

[0016] Figure 4 The images show the preparation method of the 8-12μm band high transmittance color controllable thin film on a chalcogenide glass substrate in Example 1, and the adhesion test of the product and the film system on both sides after coating.

[0017] Figure 5 The images show the preparation method of the 8-12μm band high transmittance color controllable thin film on the chalcogenide glass substrate in Example 1, and the before and after constant temperature and humidity tests of the product and the film system on both sides after the coating is completed.

[0018] Figure 6 These are photographs of the coated films and their two sides after the preparation methods of Example 1 and Comparative Example 1 are completed. The left image corresponds to Example 1, and the right image corresponds to Comparative Example 1. Detailed Implementation

[0019] It is understood that the disclosed embodiments are merely examples of this disclosure, which can be implemented in various forms. Therefore, the specific details disclosed herein should not be construed as limiting, but are intended only as the basis for the claims and as an illustrative basis to teach those skilled in the art how to implement this disclosure in various ways.

[0020] [Design Method for High Transmittance Films with Controllable Color in the 8-12μm Wavelength Band on Chalcogenide Glass Substrates]

[0021] Reference Figure 1 and Figure 2 The design method for a color-controllable high-transmittance thin film with 8-12μm wavelength on a chalcogenide glass substrate according to this disclosure includes the following steps:

[0022] Sa, the film system design uses 550nm as the reference wavelength for optical thin film design, and uses the film stack formula: Sub / M0.5(L2HL)^5 + 0.5(KL)^5 / AIR, where Sub is coated with the same film system on both sides, where Sub is a chalcogenide glass substrate, the chalcogenide glass substrate is IRG chalcogenide glass, and AIR represents air. In the film stack expression:

[0023] H represents Ge (germanium), a high-refractive-index material with a thickness of 1 / 4 wavelength.

[0024] L represents ZnS (zinc sulfide), a medium refractive index material with a thickness of 1 / 4 wavelength.

[0025] K represents YbF3 (ytterbium fluoride), a low-refractive-index material with a thickness of 1 / 4 wavelength.

[0026] M represents the IDA (a mixture of titanium and praseodymium oxide) substrate material with a thickness of 1 / 4 wavelength;

[0027] Sb, through the input membrane stack formula, generates a membrane structure of Sub / IDA / ZnS / Ge / ZnS / Ge / ZnS / YbF3 / ZnS / Air;

[0028] Sc, set the optimization target, which is the film color target and the transmittance target. The film color target is one or two adjacent colors of the seven colors of visible light: red, orange, yellow, green, cyan, blue, and violet. To design the film color of which one or two adjacent colors, the spectral reflectance peak of the design needs to be located at the wavelength of the corresponding color.

[0029] Light color Wavelength (nm) Frequency (Hz) Center wavelength (nm) red 780-622 <![CDATA[3.8×10 14 -4.8×10 14 ]]> 660 orange 622-597 <![CDATA[4.8×10 14 -5.0×10 14 ]]> 610 yellow 597-577 <![CDATA[5.0×10 14 -5.4×10 14 ]]> 580 green 577-492 <![CDATA[5.4×10 14 -6.1×10 14 ]]> 540 green 492-470 <![CDATA[6.1×10 14 -6.4×10 14 ]]> 480 blue 470-455 <![CDATA[6.4×10 14 -6.6×10 14 ]]> 460 purple 455-380 <![CDATA[6.6×10 14 -7.9×10 14 ]]> 430

[0030] Sd uses thin film design software to optimize the film thickness to obtain the optimal film thickness. The optimized film structure achieves the target transmittance in the 8-12μm wavelength band and the film color is controllable.

[0031] Se inputs the optimized film thickness into the control computer of the coating machine.

[0032] In the design method of the 8-12μm band high transmittance color controllable thin film on a chalcogenide glass substrate according to this disclosure, IDA is used as the bottom layer and as the connecting layer between the chalcogenide glass substrate and the ZnS film layer, which enhances the bonding force between the chalcogenide glass substrate and the film layer. Ge is used as a high refractive index material, YbF3 as a low refractive index material, and ZnS as a medium refractive index material, which is also used as the outermost protective layer. Thus, not only can the transmittance of the designed film structure in the 8-12μm band meet the requirements, but also the bonding between the bottom layer and the silicon substrate in the film system on both sides, as well as the water immersion test, salt spray test, adhesion test, moderate friction test, constant temperature and humidity test, low temperature test and high temperature test in the test process of the film system described later, can meet the requirements of different application scenarios.

[0033] In one example, in step Sa, the IRG chalcogenide glass is IRG04, IRG06, or IRG09.

[0034] In one example, in step Sd, for each of the two surfaces of the lens, the optimal film thickness is expressed in terms of film structure as follows:

[0035] Sub / IDA(25) / ZnS(28.51) / Ge(19.42) / ZnS(632.92) / Ge(44.57) / ZnS(249.16) / YbF3(1517.1) / ZnS(60) / Air, where the numbers in parentheses represent the film thickness in nm.

[0036] In one example, in step Sd, the average transmittance of the optimized chalcogenide glass substrate in the 8-12 μm band is greater than 99.8%.

[0037] In one example, in steps Sa to Se, the software is designed as TFCalc or Essential Macleod.

[0038] [Preparation method of high-transmittance, color-controllable thin films in the 8-12 μm wavelength band on chalcogenide glass substrates]

[0039] The method for preparing a high-transmittance, color-controllable thin film in the 8-12 μm wavelength band on a chalcogenide glass substrate according to this disclosure includes the following steps:

[0040] S1, cleaning of the chalcogenide glass substrate used as the lens and the accompanying coating before coating, and preparation of four types of film materials: IDA, ZnS, Ge and YbF3. The film material for the IDA layer is Ida (Ti-Pr-Oxide) particles with a diameter of 0.7-3.5mm, purchased from Umicore, USA, with the grade 0484519.

[0041] S2, Configuration of coating process conditions and process documents, including coating temperature, pre-coating base vacuum, film thickness, vapor deposition mode of film material, deposition rate of film material, use and parameters of ion source assisted deposition, wherein the film thickness is based on the optimal film thickness stored in the control computer of the coating machine as described in the aforementioned design method of 8-12μm band high transmittance color controllable thin film on chalcogenide glass substrate.

[0042] S3, the cleaned lenses are placed into the tooling fixture, the tooling fixture with the lenses is hung into the cavity of the coating machine, the door is closed, vacuum is drawn and heating is performed;

[0043] S4, pre-melting of film material;

[0044] S5, Ion source pre-cleaning;

[0045] S6, Coating and monitoring: Coating is performed on the first surface of the lens according to the coating process conditions and process document configuration in step S2.

[0046] S7, maintain constant temperature after coating is completed;

[0047] S8, cooling down before picking up the item;

[0048] S9. Repeat steps S1 to S8 to apply a coating to the second surface of the lens.

[0049] In the method for preparing a high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate according to this disclosure, based on steps S1 to S9 and the optimal film thickness stored in the control computer of the coating machine as described in the aforementioned design method for a high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate, as verified by subsequent tests, the prepared chalcogenide glass substrate, together with the films on both sides, can achieve the required transmittance in the 8-12 μm band. Simultaneously, it can meet the requirements of water immersion tests, salt spray tests, adhesion tests, moderate friction tests, constant temperature and humidity tests, low temperature tests, and high temperature tests, thereby satisfying the requirements of different application scenarios.

[0050] In one example, in step S1, the IRG chalcogenide glass is IRG04, IRG06, or IRG09.

[0051] In one example, in step S1, the product is a (50±0.1)mm×(10±0.1)mm convex mirror, and the accompanying plate is a (25±0.1)mm×(2±0.1)mm circular plate.

[0052] The cleaning in step S1 ensures a clean lens surface, which is beneficial for the adhesion and bonding of the coating. In one example, the lens is cleaned with ultrasonic alcohol in step S1.

[0053] In one example, in step S2, the coating temperature is 130°C; the pre-coating base vacuum is 1.5 × 10⁻⁶. -3 Pa; the film thickness in the coating process conditions and process documentation configuration is based on the optimal film thickness stored in the control computer of the coating machine in the aforementioned design method for high-transmittance, color-controllable thin films with 8-12μm wavelength on chalcogenide glass substrates; the evaporation mode of the film materials is: ZnS and YbF3 are evaporated using resistance heating, and IDA and Ge are evaporated using electron beam heating; the deposition rate of the film materials is: the deposition rate of the IDA film is... The deposition rate of the Ge film is The ZnS film deposition rate is The deposition rate of the YbF3 film is: The use of ion source-assisted deposition is as follows: no ion source is used for any of the film layers.

[0054] In one example, in step S2, the coating machine is a Leybold ARES1350.

[0055] In one example, in step S3, a vacuum is first drawn to 5 × 10⁻⁶. -2 Pa, then the cavity of the coating machine is heated, first to 130℃, then the temperature is increased by 1℃ / min every 10℃ and held for 10min to increase the temperature to 190℃, then the temperature is decreased by 1℃ / min every 10℃ and held for 10min to decrease the temperature to 130℃, and then held for 2h. That is, after heating to 130℃, the temperature is increased to 140℃ at 1℃ / min and held for 10 min, then increased to 150℃ at 1℃ / min and held for 10 min, then increased to 160℃ at 1℃ / min and held for 10 min, then increased to 170℃ at 1℃ / min and held for 10 min, then increased to 180℃ at 1℃ / min and held for 10 min, then increased to 190℃ at 1℃ / min and held for 10 min, then decreased to 180℃ at 1℃ / min and held for 10 min, then decreased to 170℃ at 1℃ / min and held for 10 min, then decreased to 160℃ at 1℃ / min and held for 10 min, then decreased to 150℃ at 1℃ / min and held for 10 min, then decreased to 140℃ at 1℃ / min and held for 10 min, and finally decreased to 130℃ at 1℃ / min and held for 2 h. In addition, in one example, in step S3, heating to 130°C is performed by heating from room temperature to 130°C at a rate of 5°C / min.

[0056] In step S4, the pre-melted membrane material undergoes degassing and impurity removal to ensure its purity. In one example, in step S4, when the vacuum reaches (4.0-5.0)×10⁻⁶... -3At step Pa, the film material is pre-melted. After pre-melting, the temperature of the cavity of the coating machine reaches 130℃ and is maintained at a constant temperature for 10 minutes. Specifically, for example, in step S4, the pre-melting treatment uses both electron beam heating and resistance heating. For Ge film material, the electron beam heating current is 260-290mA; for IDA film material, the electron beam heating current is 420-480mA; for ZnS film material, the resistance heating current is 720-760mA; and for YbF3 film material, the resistance heating current is 860-900mA.

[0057] Step S5, ion source cleaning, removes surface impurities from the chalcogenide glass substrate, resulting in a cleaner substrate surface and increased film adhesion. In one example, the cavity vacuum level reaches (1.5 ± 0.1) × 10⁻⁶. -3 Pa, start the ion source to perform ion cleaning on the lens. The ion source is an APS ion source. The parameters of the APS ion source are: ion source voltage 700±50V, ion source current 700±50mA, accelerating voltage 500±50V, accelerating current 700±50mA, pure argon gas is used for the ion source, the argon gas flow rate of the ion source is 60±5sccm, the argon gas flow rate of the neutralizer is 8±0.13sccm, and the cleaning time is 300±2s.

[0058] In one example, in step S6, when depositing each film layer, no gas is introduced from outside the coating machine into the cavity of the coating machine, and the cavity of the coating machine is kept evacuated and the coating temperature is kept at 130°C; each film layer is deposited at a temperature of 130°C in the cavity of the coating machine; the film thickness is monitored by using the crystal oscillator method with the corresponding crystal oscillators of multiple crystal oscillators of the crystal controller; after ion source cleaning, the crystal controller controls the new crystal oscillator among the multiple crystal oscillators to work accordingly, and the crystal oscillator frequency is not less than 5850Hz.

[0059] In one example, in step S7, after the plating is completed, the cavity is kept at 130°C for 40 minutes.

[0060] In one example, in step S8, after step S7 is completed, the temperature is first lowered to 110°C at 1°C / min and held for 5 minutes, then lowered to 90°C at 1°C / min and held for 5 minutes, and then lowered to below 60°C at 1°C / min before the door is opened and the item is taken out.

[0061] [test]

[0062] Example 1

[0063] Part 1: Design Methods for High-Transmittance Color-Controllable Thin Films in the 8-12μm Wavelength Band on Chalcogenide Glass Substrates

[0064] The design method for high-transmittance, color-controllable thin films with 8-12μm wavelength on chalcogenide glass substrates involves the following steps:

[0065] Sa, the film system design uses 550nm as the reference wavelength for optical thin film design. In TFCalc, the film stack formula is used: Sub / M0.5(L2HL)^5 + 0.5(KL)^5 / AIR, where Sub has the same film system deposited on both sides. Sub is a chalcogenide glass substrate, specifically IRG06 chalcogenide glass, and AIR represents air. In the film stack expression:

[0066] H represents Ge (germanium), a high-refractive-index material with a thickness of 1 / 4 wavelength.

[0067] L represents ZnS (zinc sulfide), a medium refractive index material with a thickness of 1 / 4 wavelength.

[0068] K represents YbF3 (ytterbium fluoride), a low-refractive-index material with a thickness of 1 / 4 wavelength.

[0069] M represents the IDA (a mixture of titanium and praseodymium oxide) substrate material with a thickness of 1 / 4 wavelength.

[0070] Sb, through the input membrane stack formula, generates a membrane structure of Sub / IDA / ZnS / Ge / ZnS / Ge / ZnS / YbF3 / ZnS / Air;

[0071] Sc, set the optimization target, which is the film color target and the transmittance target. The film color target is one or two adjacent colors of the seven colors of visible light: red, orange, yellow, green, cyan, blue, and violet. To design the film color of which one or two adjacent colors, the spectral reflectance peak of the design needs to be located at the wavelength of the corresponding color.

[0072] Light color Wavelength (nm) Frequency (Hz) Center wavelength (nm) red 780-622 <![CDATA[3.8×10 14 -4.8×10 14 ]]> 660 orange 622-597 <![CDATA[4.8×10 14 -5.0×10 14 ]]> 610 yellow 597-577 <![CDATA[5.0×10 14 -5.4×10 14 ]]> 580 green 577-492 <![CDATA[5.4×10 14 -6.1×10 14 ]]> 540 green 492-470 <![CDATA[6.1×10 14 -6.4×10 14 ]]> 480 blue 470-455 <![CDATA[6.4×10 14 -6.6×10 14 ]]> 460 purple 455-380 <![CDATA[6.6×10 14 -7.9×10 14 ]]> 430

[0073] The target color of the membrane system is yellow-green, and the spectral reflectance peak is set at 510-580nm.

[0074] Sd, using the thin film design software TFCalc, optimized the film thickness to obtain the optimal film thickness. The optimized film structure achieved the target transmittance in the 8-12μm wavelength range and the film color was controllable.

[0075] In step Sd, for each of the two sides of the lens, the optimal coating thickness is determined by the film thickness.

[0076] The layer structure is represented as:

[0077] Sub / IDA(25) / ZnS(28.51) / Ge(19.42) / ZnS(632.92) / Ge(44.57) / ZnS(249.1

[0078] 6) / YbF3(1517.1) / ZnS(60) / Air, where the numbers in parentheses represent the film thickness, and the film thickness is expressed as a single unit.

[0079] The position is nm;

[0080] Se inputs the optimized film thickness into the control computer of the coating machine, which is a Leybold ARES1350.

[0081] Part 2: Preparation method of high-transmittance, color-controllable thin films in the 8-12 μm band on chalcogenide glass substrates

[0082] The preparation method of a high-transmittance, color-controllable thin film in the 8-12 μm wavelength band on a chalcogenide glass substrate comprises the following steps:

[0083] S1. Cleaning of the chalcogenide glass substrate and the accompanying coating piece before coating, and preparation of four coating materials: IDA, ZnS, Ge and YbF3. The chalcogenide glass substrate is IRG06 chalcogenide glass. The product is a 50mm×10mm convex lens, and the accompanying coating piece is a 25mm×2mm circular piece. The lens is cleaned with ultrasonic alcohol. The coating material for the IDA layer is Ida (Ti-Pr-Oxide) particles with a diameter of 0.7-3.5mm, purchased from Umicore, USA, with the grade 0484519.

[0084] S2, Configuration of coating process conditions and process documents, including coating temperature, pre-coating base vacuum, film thickness, vapor deposition mode of film material, deposition rate of film material, use and parameters of ion source assisted deposition, wherein the film thickness is based on the optimal film thickness stored in the control computer of the coating machine as described in the design method of 8-12μm band high transmittance color controllable thin film on chalcogenide glass substrate in the first part above.

[0085] In step S2,

[0086] The coating temperature is 130℃;

[0087] The base vacuum before plating is 1.5 × 10⁻⁶. -3 Pa;

[0088] The film thickness in the configuration of coating process conditions and process documents is based on the optimal film thickness stored in the control computer of the coating machine as described in the design method of 8-12μm band high transmittance color controllable thin film on chalcogenide glass substrate in the first part above.

[0089] The evaporation mode of the film materials is as follows: ZnS and YbF3 are evaporated using resistance heating, while IDA and Ge are evaporated using electron beam heating.

[0090] The deposition rate of the film material is: The deposition rate of the IDA film layer is The deposition rate of the Ge film is The ZnS film deposition rate is The deposition rate of the YbF3 film is:

[0091] The use of ion source-assisted deposition is as follows: no ion source is used for any of the film layers;

[0092] S3. Place the cleaned lenses into the fixture, hang the fixture with the lenses in it into the cavity of the coating machine, close the door, and first evacuate to 5×10. -2 Pa, then the coating machine cavity is heated, from room temperature to 130℃ at 5℃ / min, then to 140℃ at 1℃ / min and held for 10 min, then to 150℃ at 1℃ / min and held for 10 min, then to 160℃ at 1℃ / min and held for 10 min, then to 170℃ at 1℃ / min and held for 10 min, then to 180℃ at 1℃ / min and held for 10 min, then at 1℃ / min... The temperature is increased to 190℃ and held for 10 min at a rate of 1℃ / min, then decreased to 180℃ and held for 10 min at a rate of 1℃ / min, then decreased to 170℃ and held for 10 min at a rate of 1℃ / min, then decreased to 160℃ and held for 10 min at a rate of 1℃ / min, then decreased to 150℃ and held for 10 min at a rate of 1℃ / min, then decreased to 140℃ and held for 10 min at a rate of 1℃ / min, and finally decreased to 130℃ and held for 2 h at a rate of 1℃ / min.

[0093] S4, pre-melting of the film material, when the vacuum reaches 5.0×10 -3 When Pa, the film material is pre-melted. After the film material is pre-melted, the temperature of the cavity of the coating machine reaches 130℃ and is kept constant for 10 minutes.

[0094] In step S4, the pre-melting process employs both electron beam heating and resistance heating.

[0095] For Ge film materials, the electron beam heating current is 265mA;

[0096] For IDA film material, the electron beam heating current is 450mA;

[0097] For ZnS film material, the resistance heating current is 740mA;

[0098] For YbF3 film material, the resistance heating current is 880mA;

[0099] S5, ion source pre-cleaning, chamber vacuum reaches 1.5×10 -3Pa, start the ion source to perform ion cleaning on the lens. The ion source is an APS ion source. The parameters of the APS ion source are: ion source voltage is 700V, ion source current is 700mA, acceleration voltage is 500V, acceleration current is 700mA, the ion source uses pure argon gas, the argon gas flow rate of the ion source is 60sccm, the argon gas flow rate of the neutralizer is 8sccm, and the cleaning time is 300s.

[0100] S6, Coating and monitoring: Coating is performed on the first surface of the lens according to the coating process conditions and process document configuration in step S2.

[0101] In step S6,

[0102] When depositing each film layer, no gas is introduced from outside the coating machine into the cavity of the coating machine, and the cavity of the coating machine is kept evacuated while maintaining the coating temperature at 130°C.

[0103] Each film layer is deposited at a temperature of 130°C in the cavity of the coating machine;

[0104] The crystal oscillator method uses multiple crystal oscillators of a crystal controller to monitor film thickness. After ion source cleaning, the crystal controller controls a new crystal oscillator among the multiple crystal oscillators to operate accordingly.

[0105] The vibration frequency is 5990Hz;

[0106] S7, after plating, keep the cavity at 130℃ for 40 minutes;

[0107] S8. After step S7 is completed, the temperature is first lowered to 110℃ at 1℃ / min and held for 5min, then lowered to 90℃ at 1℃ / min and held for 5min, and then lowered to 60℃ at 1℃ / min. The door is then opened and the part is taken out.

[0108] S9. Repeat steps S1 to S8 to apply a coating to the second surface of the lens.

[0109] Comparative Example 1

[0110] Except for step 3, where the temperature is raised from room temperature to 130°C at a rate of 5°C / min and held for 2 hours (i.e., after heating to 130°C, neither gradient heating nor gradient cooling is performed), the rest is the same as in Example 1.

[0111] Comparative Example 2

[0112] In step S6, argon gas is introduced from outside the coating machine into the cavity of the coating machine during the deposition of each film layer, and the cavity of the coating machine is kept evacuated to ensure that the coating vacuum degree is maintained at 5×10. -3 Except for Pa, the rest is the same as in Example 1.

[0113] Figure 2 This is a transmittance curve designed using the design method of the 8-12μm band high transmittance film with controllable color on a chalcogenide glass substrate in Example 1. From... Figure 2 It can be seen that the average transmittance of the chalcogenide glass substrate and the films on both sides is 99.81% (i.e., more than 99.8%) in the 8-12μm band.

[0114] Figure 3 This is a transmittance curve of the substrate and the film system on both sides after coating, showing the preparation method of the high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate in Example 1. Figure 3 It can be seen that the average transmittance of the substrate and the film system on both sides is 98.1% (i.e., more than 98%).

[0115] The products of Example 1 and Comparative Examples 1-2, along with the film systems on both sides, were subjected to the following overall performance tests.

[0116] Water immersion test: Take tap water and conduct a water immersion test for 2 hours, and observe whether the film layer on each surface is peeled off or whether the film layer on each surface is cracked.

[0117] Salt spray test: Neutral salt spray test for 24 hours, observe whether the film layer on each surface peels off or cracks.

[0118] Adhesion test: Apply 3M tape by hand and pull the tape in the opposite direction to the adhesive end on each side to observe whether the film layer is pulled up.

[0119] Moderate friction test: The membrane layer is subjected to 50 rubs with a rubber friction head wrapped with degreased cloth at a pressure of 4.9N, and the presence of scratches or damage is observed.

[0120] Constant temperature and humidity test: In a constant temperature and humidity chamber, at 50℃ and 95% relative humidity for 24 hours, observe whether the film layer on each surface peels off or cracks.

[0121] Low temperature test: In a low temperature chamber, at -40℃ for 24 hours, observe whether the film layer on each surface peels off or cracks.

[0122] High temperature test: In a high temperature chamber, at 85℃ for 24 hours, observe whether the film layer on each surface peels off or cracks.

[0123] The product of Example 1, along with the film systems on both sides, passed all tests including immersion testing, salt spray testing, adhesion testing, moderate friction testing, constant temperature and humidity testing, low temperature testing, and high temperature testing. Figure 4 The images show the preparation method of the 8-12μm band high transmittance color controllable thin film on a chalcogenide glass substrate in Example 1, and the adhesion test of the product and the film system on both sides after coating. Figure 5The images show the preparation method of the 8-12μm band high transmittance color controllable thin film on a chalcogenide glass substrate in Example 1, and the before and after constant temperature and humidity tests of the product and the film system on both sides after coating. Figure 6 These are photographs of the coated films and their two sides after the preparation methods of Example 1 and Comparative Example 1 are completed. The left image corresponds to Example 1, and the right image corresponds to Comparative Example 1.

[0124] Table 1 shows the average transmittance, results of various tests, and film color of Example 1 and Comparative Examples 1-2.

[0125] Table 1 shows the average transmittance, results of various tests, and film color of Examples 1 and Comparative Examples 1-2.

[0126]

[0127] Several exemplary embodiments have been described in detail above, but this document is not intended to limit itself to the explicitly disclosed combinations. Therefore, unless otherwise stated, the various features disclosed herein can be combined to form several other combinations, which are not shown for simplicity.

Claims

1. A method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm wavelength band, characterized in that, Including the following steps: S1, cleaning of the chalcogenide glass substrate used as the lens and the accompanying coating before coating, and preparation of four types of film materials: IDA (titanium and praseodymium oxide mixture), ZnS, Ge and YbF3. The film material for the IDA layer is Ida (Ti-Pr-Oxide) particles with a diameter of 0.7-3.5mm. S2, Configuration of coating process conditions and process documents. The configuration of coating process conditions and process documents includes coating temperature, pre-coating base vacuum, film thickness, film deposition mode, film deposition rate, and the use and parameters of ion source-assisted deposition. The film thickness is based on the optimal film thickness stored in the coating machine's control computer. For each of the two sides of the lens, the optimal film thickness is expressed in terms of film structure as follows: Sub / IDA(25) / ZnS(28.51) / Ge(19.42) / ZnS(632.92) / Ge(44.57) / ZnS(249.16) / YbF3(1517.1) / ZnS(60) / Air, where the numbers in parentheses represent the film thickness in nm. S3, the cleaned lenses are placed into the tooling fixture, the tooling fixture with the lenses is hung into the cavity of the coating machine, the door is closed, vacuum is drawn and heating is performed; S4, pre-melting of film material; S5, Ion source pre-cleaning; S6, Coating and monitoring: Coating is performed on the first surface of the lens according to the coating process conditions and process document configuration in step S2. S7, maintain constant temperature after coating is completed; S8, cooling down before picking up the item; S9. Repeat steps S1 to S8 to apply a coating to the second surface of the lens.

2. The method for preparing a high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate according to claim 1, characterized in that, In step S1, IRG chalcogenide glasses are IRG04, IRG06 or IRG09; The product is a (50±0.1)mm×(10±0.1)mm convex mirror, and the accompanying plate is a (25±0.1)mm×(2±0.1)mm circular plate; The lenses are cleaned using ultrasonic alcohol cleaning.

3. The method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band according to claim 1, characterized in that, In step S2, The coating temperature is 130°C; The base vacuum before plating is 1.5 × 10⁻⁶. -3 Pa; The evaporation mode of the film materials is as follows: ZnS and YbF3 are evaporated using resistance heating, while IDA and Ge are evaporated using electron beam heating. The deposition rates of the membrane materials are as follows: 3 Å / s for IDA membrane, 4 Å / s for Ge membrane, 5 Å / s for ZnS membrane, and 3 Å / s for YbF3 membrane. The use of ion source-assisted deposition is as follows: no ion source is used for any of the film layers; In step S2, the coating machine is a Leybold ARES1350.

4. The method for preparing a high-transmittance, color-controllable thin film in the 8-12 μm band on a chalcogenide glass substrate according to claim 1, characterized in that, In step S3, a vacuum is first drawn to 5×10⁻⁶. -2 Pa, then the cavity of the coating machine is heated, first to 130°C, then the temperature is increased by 1°C / min every 10°C and held for 10min to reach 190°C, then the temperature is decreased by 1°C / min every 10°C and held for 10min to reach 130°C, and then held for 2h. In step S3, heating to 130°C is achieved by heating from room temperature to 130°C at a rate of 5°C / min.

5. The method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band according to claim 1, characterized in that, In step S4, when the vacuum reaches (4.0-5.0)×10 -3 When Pa, the film material is pre-melted. After the film material is pre-melted, the temperature of the cavity of the coating machine reaches 130°C and is kept constant for 10 minutes. In step S4, the pre-melting process employs both electron beam heating and resistance heating. For Ge film materials, the electron beam heating current is 260-290mA; For IDA film material, the electron beam heating current is 420-480mA; For ZnS film materials, the resistance heating current is 720-760mA; For YbF3 film material, the resistance heating current is 860-900mA.

6. The method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band according to claim 1, characterized in that, In step S5, The cavity vacuum level reaches (1.5±0.1)×10 -3 Pa, start the ion source to perform ion cleaning on the lens. The ion source is an APS ion source. The parameters of the APS ion source are: ion source voltage 700±50V, ion source current 700±50mA, accelerating voltage 500±50V, accelerating current 700±50mA, pure argon gas is used for the ion source, the argon gas flow rate of the ion source is 60±5sccm, the argon gas flow rate of the neutralizer is 8±0.13sccm, and the cleaning time is 300±2s.

7. The method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band according to claim 1, characterized in that, In step S6, When depositing each film layer, no gas is introduced from outside the coating machine into the cavity of the coating machine, and the cavity of the coating machine is kept evacuated and the coating temperature is kept at 130°C. Each film layer is deposited at a temperature of 130°C in the cavity of the coating machine; The crystal oscillator method is used to monitor the film thickness by using the corresponding crystal oscillators of multiple crystal oscillators in the crystal controller. After cleaning with the ion source, the crystal controller controls the new crystal oscillator in the multiple crystal oscillators to work accordingly, and the crystal oscillator frequency is not less than 5850Hz.

8. The method for preparing a high-transmittance, color-controllable thin film with a chalcogenide glass substrate in the 8-12 μm band according to claim 1, characterized in that, In step S7, after the plating is completed, the cavity is kept at 130°C for 40 minutes; In step S8, after step S7 is completed, the temperature is first lowered to 110°C at a rate of 1°C / min and held for 5 minutes, then lowered to 90°C at a rate of 1°C / min and held for 5 minutes, and then lowered to below 60°C at a rate of 1°C / min before the door is opened and the part is taken out.

Images