Method for depositing a dual-band antireflection film system on a chalcogenide glass substrate

Abstract

A method for preparing a dual-band antireflection coating system on a chalcogenide glass substrate includes the following steps: S1, cleaning the surfaces of the substrate (VIG04 substrate) and the product, which serve as the chalcogenide glass substrate for the lens; S2, placing the lens in a fixture into a vacuum coating machine, setting the temperature to 130°C; S3, starting vacuum extraction and ion source cleaning; S4, maintaining the vacuum level, depositing a first YF3 film layer on the first surface of the lens; S5, depositing a first ZnSe film layer; S6, depositing a second YF3 film layer; S7, ... S8. Evaporate the second ZnSe film layer; S9. Evaporate the third ZnSe film layer; S10. Evaporate the fourth YF3 film layer; S11. Evaporate the fourth ZnSe film layer; S12. Evaporate the fifth YF3 film layer; S13. Evaporate the LaF3 film layer; S14. After the vacuum chamber cools to below 90°C, remove the tooling fixture along with the substrate and product; S15. Optionally, in another vacuum coating machine, evaporate the AF film layer without using an ion source to assist in evaporation; S16. Repeat steps S1 to S15.

Description

Technical Field

[0001] This disclosure relates to the infrared field, and more specifically to a method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate. Background Technology

[0002] Chalcogenide glasses are widely used as infrared lens materials in infrared imaging systems. With the increasing prevalence of infrared technology, the requirements for infrared coatings are becoming more stringent. Therefore, further improvements are needed to the antireflective coating systems deposited on chalcogenide glass substrates. Summary of the Invention

[0003] In view of the problems existing in the background art, the purpose of this disclosure is to provide a method for preparing an antireflection film system deposited on a chalcogenide glass substrate, which can meet the emissivity requirements of the 1064nm and 8-12μm infrared dual-band.

[0004] Therefore, a method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate includes the following steps:

[0005] S1, the surface of the coating sheet and the product, which serve as the chalcogenide glass substrate for the lens, are cleaned. The chalcogenide glass substrate is a VIG04 substrate, and the thickness of the coating sheet is 0.9-1.5mm.

[0006] S2, Place the cleaned lens into the fixture, and hang the fixture with the lens in it into the cavity of the vacuum coating machine. The temperature of the cavity is set to 130℃.

[0007] S3, the vacuum coating machine starts pumping vacuum, and the vacuum level reaches 1.5×10. -3 Pa, turn on the ion source of the auxiliary coating of the vacuum coating machine for cleaning. The cleaning time is 6 minutes. The anode voltage of the ion source is 220V, the anode current is 1.0-2.5A, and the emitter current is 1.3-1.5A.

[0008] S4, maintaining the aforementioned vacuum level, deposit a first YF3 film layer on the first surface of the lens by vapor deposition. The deposition rate of the first YF3 film layer is 0.8 nm / s, and the thickness of the first YF3 film layer is controlled to be 70 nm ± 3 nm. Ion source assisted vapor deposition.

[0009] S5, deposit a first ZnSe film on the deposited first YF3 film. The deposition rate of the first ZnSe film is 0.8 nm / s, and the thickness of the first ZnSe film is controlled to be 91 nm ± 3 nm. Ion source assisted evaporation.

[0010] S6, a second YF3 film layer is deposited on the first ZnSe film layer. The deposition rate of the second YF3 film layer is 0.8 nm / s, and the film thickness of the second YF3 film layer is controlled to be 80 nm ± 3 nm. Ion source assisted evaporation.

[0011] S7, a second ZnSe film is deposited on the deposited second YF3 film. The deposition rate of the second ZnSe film is 0.8 nm / s, and the thickness of the second ZnSe film is controlled to be 90 nm ± 3 nm. Ion source assisted evaporation.

[0012] S8, a third YF3 film is deposited on the deposited second ZnSe film. The deposition rate of the third YF3 film is 0.8 nm / s, and the thickness of the third YF3 film is controlled to be 83 nm ± 3 nm. Ion source assisted evaporation.

[0013] S9, a third ZnSe film is deposited on the deposited third YF3 film. The deposition rate of the third ZnSe film is 0.8 nm / s, and the thickness of the third ZnSe film is controlled to be 100 nm ± 4 nm. Ion source assisted evaporation.

[0014] S10, a fourth YF3 film layer is deposited on the deposited third ZnSe film layer. The deposition rate of the fourth YF3 film layer is 0.8 nm / s, and the film thickness of the fourth YF3 film layer is controlled to be 760 nm ± 5 nm. Ion source assisted evaporation.

[0015] S11, a fourth ZnSe film is deposited on the deposited fourth YF3 film. The deposition rate of the fourth ZnSe film is 0.8 nm / s, and the thickness of the fourth ZnSe film is controlled to be 100 nm ± 4 nm. Ion source assisted evaporation.

[0016] S12, a fifth YF3 film layer is deposited on the deposited fourth ZnSe film layer. The deposition rate of the fifth YF3 film layer is 0.8 nm / s, and the film thickness of the fifth YF3 film layer is controlled to be 126 nm ± 4 nm. Ion source assisted evaporation.

[0017] S13, a LaF3 film is deposited on the fifth YF3 film layer. The deposition rate of the LaF3 film layer is 0.6 nm / s, and the film thickness of the LaF3 film layer is controlled to be 40 nm ± 2 nm. Ion source assisted evaporation.

[0018] S14. After the LaF3 film is deposited by vapor deposition, wait for the vacuum chamber to cool to below 90°C and then take out the tooling fixture, along with the substrate and the product.

[0019] Optional S15, in another vacuum coating machine, deposits an AF film on the deposited LaF3 film without using an ion source-assisted evaporation.

[0020] S16, repeat steps S1 to S15, and sequentially deposit the first YF3 film, the first ZnSe film, the second YF3 film, the second ZnSe film, the third YF3 film, the third ZnSe film, the fourth YF3 film, the fourth ZnSe film, the fifth YF3 film, the LaF3 film, and the optional AF film on the opposite second side of the lens.

[0021] The beneficial effects of this disclosure are as follows: In the dual-band antireflection coating system deposited on the chalcogenide glass substrate of this disclosure, by depositing a first YF3 film with a thickness of 70nm±3nm, a first ZnSe film with a thickness of 91nm±3nm, a second YF3 film with a thickness of 80nm±3nm, a second ZnSe film with a thickness of 90nm±3nm, a third YF3 film with a thickness of 83nm±3nm, a third ZnSe film with a thickness of 100nm±4nm, a fourth YF3 film with a thickness of 760nm±5nm, a fourth ZnSe film with a thickness of 100nm±4nm, a fifth YF3 film with a thickness of 126nm±4nm, and a fourth ZnSe film with a thickness of 40nm±2nm on both sides of the chalcogenide glass substrate used as a lens and the product, the following layers are achieved: A LaF3 film with a thickness of nm and an optional AF film, ten layers on each side (eleven layers if the AF film is selected) will serve as the antireflective coating system for the product. Based on tests of the 1064nm (near-infrared) and 8-12μm (far-infrared) bands of the substrate, when the AF film is not deposited in step S15, the transmittance in the 1064nm band is 97.42%, and the transmittance in the 8-12μm band is 95.58%; when the AF film is deposited in step S15, the transmittance in the 1064nm band is 96.27%, and the transmittance in the 8-12μm band is 95.12%. In other words, the chalcogenide glass substrate together with the antireflective coating system on both sides can meet the dual-band transmittance requirements. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a structure in which a dual-band antireflection coating system is deposited on both sides of a substrate including a chalcogenide glass substrate and a product, according to the preparation method of the dual-band antireflection coating system deposited on a chalcogenide glass substrate disclosed herein.

[0023] Figure 2 This is a curve showing the transmittance of the dual-band antireflection film system coated on both sides of the substrate in Example 1 at the 1064nm wavelength, wherein step S15, which involves evaporating the AF film layer, was not performed.

[0024] Figure 3 This is a curve showing the transmittance of the dual-band antireflection film system coated on both sides of the substrate in Example 1 in the 8-12μm infrared band. In this case, step S15, which involves evaporating the AF film layer, was not performed.

[0025] Figure 4This is a curve showing the transmittance of the dual-band antireflection film system deposited on both sides of the substrate in Example 1 at the 1064nm wavelength, wherein step S15 involves the vapor deposition of the AF film layer.

[0026] Figure 5 This is a curve showing the transmittance of the dual-band antireflection film system coated on both sides of the substrate in Example 1 in the 8-12μm infrared band, wherein step S15 is performed by evaporating the AF film layer. Detailed Implementation

[0027] The accompanying drawings illustrate embodiments of this disclosure, and it will be 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.

[0028] [Preparation method of dual-band antireflection coating system deposited on chalcogenide glass substrate]

[0029] The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to this disclosure includes the following steps:

[0030] S1, the surface of the coating sheet and the product, which serve as the chalcogenide glass substrate for the lens, are cleaned. The chalcogenide glass substrate is a VIG04 substrate, and the thickness of the coating sheet is 0.9-1.5mm.

[0031] S2, Place the cleaned lens into the fixture, and hang the fixture with the lens in it into the cavity of the vacuum coating machine. The temperature of the cavity is set to 130℃.

[0032] S3, the vacuum coating machine starts pumping vacuum, and the vacuum level reaches 1.5×10. -3 Pa, turn on the ion source of the auxiliary coating of the vacuum coating machine for cleaning. The cleaning time is 6 minutes. The anode voltage of the ion source is 220V, the anode current is 1.0-2.5A, and the emitter current is 1.3-1.5A.

[0033] S4, maintaining the aforementioned vacuum level, deposit a first YF3 film layer on the first surface of the lens by vapor deposition. The deposition rate of the first YF3 film layer is 0.8 nm / s, and the thickness of the first YF3 film layer is controlled to be 70 nm ± 3 nm. Ion source assisted vapor deposition.

[0034] S5, deposit a first ZnSe film on the deposited first YF3 film. The deposition rate of the first ZnSe film is 0.8 nm / s, and the thickness of the first ZnSe film is controlled to be 91 nm ± 3 nm. Ion source assisted evaporation.

[0035] S6, a second YF3 film layer is deposited on the first ZnSe film layer. The deposition rate of the second YF3 film layer is 0.8 nm / s, and the film thickness of the second YF3 film layer is controlled to be 80 nm ± 3 nm. Ion source assisted evaporation.

[0036] S7, a second ZnSe film is deposited on the deposited second YF3 film. The deposition rate of the second ZnSe film is 0.8 nm / s, and the thickness of the second ZnSe film is controlled to be 90 nm ± 3 nm. Ion source assisted evaporation.

[0037] S8, a third YF3 film is deposited on the deposited second ZnSe film. The deposition rate of the third YF3 film is 0.8 nm / s, and the thickness of the third YF3 film is controlled to be 83 nm ± 3 nm. Ion source assisted evaporation.

[0038] S9, a third ZnSe film is deposited on the deposited third YF3 film. The deposition rate of the third ZnSe film is 0.8 nm / s, and the thickness of the third ZnSe film is controlled to be 100 nm ± 4 nm. Ion source assisted evaporation.

[0039] S10, a fourth YF3 film layer is deposited on the deposited third ZnSe film layer. The deposition rate of the fourth YF3 film layer is 0.8 nm / s, and the film thickness of the fourth YF3 film layer is controlled to be 760 nm ± 5 nm. Ion source assisted evaporation.

[0040] S11, a fourth ZnSe film is deposited on the deposited fourth YF3 film. The deposition rate of the fourth ZnSe film is 0.8 nm / s, and the thickness of the fourth ZnSe film is controlled to be 100 nm ± 4 nm. Ion source assisted evaporation.

[0041] S12, a fifth YF3 film layer is deposited on the deposited fourth ZnSe film layer. The deposition rate of the fifth YF3 film layer is 0.8 nm / s, and the film thickness of the fifth YF3 film layer is controlled to be 126 nm ± 4 nm. Ion source assisted evaporation.

[0042] S13, a LaF3 film is deposited on the fifth YF3 film layer. The deposition rate of the LaF3 film layer is 0.6 nm / s, and the film thickness of the LaF3 film layer is controlled to be 40 nm ± 2 nm. Ion source assisted evaporation.

[0043] S14. After the LaF3 film is deposited by vapor deposition, wait for the vacuum chamber to cool to below 90°C and then take out the tooling fixture, along with the substrate and the product.

[0044] Optional S15, in another vacuum coating machine, deposits an AF film on the deposited LaF3 film without using an ion source-assisted evaporation.

[0045] S16, repeat steps S1 to S15, and sequentially deposit the first YF3 film, the first ZnSe film, the second YF3 film, the second ZnSe film, the third YF3 film, the third ZnSe film, the fourth YF3 film, the fourth ZnSe film, the fifth YF3 film, the LaF3 film, and the optional AF film on the opposite second side of the lens.

[0046] In the dual-band antireflection coating system deposited on the chalcogenide glass substrate of this disclosure, a first YF3 film with a thickness of 70nm±3nm, a first ZnSe film with a thickness of 91nm±3nm, a second YF3 film with a thickness of 80nm±3nm, a second ZnSe film with a thickness of 90nm±3nm, a third YF3 film with a thickness of 83nm±3nm, a third ZnSe film with a thickness of 100nm±4nm, a fourth YF3 film with a thickness of 760nm±5nm, a fourth ZnSe film with a thickness of 100nm±4nm, a fifth YF3 film with a thickness of 126nm±4nm, and a third ZnSe film with a thickness of 40nm±2nm are deposited on both sides of the chalcogenide glass substrate used as a lens. The LaF3 film and optional AF film, with ten layers on each side (eleven layers if the AF film is selected), will serve as the antireflective coating system for the product. Based on tests of the 1064nm (near-infrared) and 8-12μm (far-infrared) bands of the substrate, when the AF film is not deposited in step S15, the transmittance in the 1064nm band is 97.42%, and the transmittance in the 8-12μm band is 95.58%; when the AF film is deposited in step S15, the transmittance in the 1064nm band is 96.27%, and the transmittance in the 8-12μm band is 95.12%. In other words, the chalcogenide glass substrate, together with the antireflective coating system on both sides, can meet the dual-band transmittance requirements.

[0047] In the dual-band antireflective coating system deposited on the chalcogenide glass substrate of this disclosure, the total thickness of the ten coating layers (i.e., excluding the AF coating layer) deposited on the first and second surfaces opposite to the first and second surfaces of the chalcogenide glass substrate serving as a lens is 1540 nm ± 34 nm.

[0048] The surface cleaning in step S1 helps improve the surface condition of the first and second surfaces of the substrate and the product, and helps to improve the bonding performance between the antireflective coating system on each surface and the corresponding surface of the substrate and the product.

[0049] The temperature of the cavity in step S2 helps to eliminate stress on each side (i.e., each of the first and second sides) of the substrate and the product with respect to the first YF3 film, while also facilitating the growth of the film on each side of the substrate and the product.

[0050] Step S3 uses an ion source for cleaning. The bombardment and sputtering effects of argon ions ionized by the working gas argon will cause impurities, oil molecules, and oxides adsorbed on the surface of the substrate and the substrate to detach from the substrate surface, thereby greatly improving the interface state and helping to improve the bonding performance between the first YF3 film layer and the chalcogenide glass substrate. At the same time, the bombardment of the chalcogenide glass substrate by argon ions can heat the surface of the chalcogenide glass substrate, which helps the growth of the first YF3 film layer and reduces the growth stress of the first YF3 film layer.

[0051] In steps S4 to S13, ion source-assisted evaporation helps the corresponding film layer grow, improves adhesion and hardness, and reduces film layer stress through ion bombardment.

[0052] In steps S3 to S13, the fourth YF3 film layer in the middle has the largest film thickness. The film thickness of the fourth YF3 film layer is significantly different from that of the other films above and below it, and they are on completely different scales. This allows the transition from the chalcogenide glass substrate to the ultra-thick fourth YF3 film layer by using multiple thin YF3 / ZnSe film layers as transition layers. This is beneficial for buffering and releasing the film stress between adjacent film layers below the fourth YF3 film layer, and for reducing the overall film thickness on each surface of the chalcogenide glass substrate.

[0053] It should be noted that in the preparation method of the dual-band antireflection film system deposited on the chalcogenide glass substrate disclosed herein, the co-coating sheet is a sheet with flat surfaces on both sides of equal thickness, while the product may differ from the co-coating sheet in shape and size according to actual needs.

[0054] In one example, in step S1, the thickness of the plating sheet is 1.0 mm.

[0055] In one example, in step S1, the lens surface is cleaned using ultrasound or by hand.

[0056] In one example, in step S3, the anode current is 1.2A and the emitter current is 1.5A.

[0057] In one example, in step S3, the ion source is a Hall ion source.

[0058] In one example, in step S4, the thickness of the first YF3 film is controlled to be 70 nm; in step S5, the thickness of the first ZnSe film is controlled to be 91 nm; in step S6, the thickness of the second YF3 film is controlled to be 80 nm; in step S7, the thickness of the second ZnSe film is controlled to be 90 nm; in step S8, the thickness of the third YF3 film is controlled to be 83 nm; in step S9, the thickness of the third ZnSe film is controlled to be 100 nm; in step S10, the thickness of the fourth YF3 film is controlled to be 760 nm; in step S11, the thickness of the fourth ZnSe film is controlled to be 100 nm; in step S12, the thickness of the fifth YF3 film is controlled to be 126 nm; and in step S13, the thickness of the LaF3 film is controlled to be 40 nm.

[0059] In one example, in steps S4, S6, S8, S10, and S12, a neutralizer is provided for the ion source. The parameters of the neutralizer are: neutralization current of 0.5A, use of argon to form the neutralizing gas, and a neutralizing gas flow rate of 8 sccm. The anode voltage of the ion source is 180V, the anode current is 2A, and argon and oxygen are used as working gases, with an argon flow rate of 20 sccm and an oxygen flow rate of 80 sccm. The use of oxygen increases the compactness of the YF3 film.

[0060] In one example, in steps S5, S7, S9, S11 and S13, a neutralizer is provided for the ion source. The parameters of the neutralizer are: neutralization current of 0.5A, neutralization gas is formed by argon, and the flow rate of the neutralization gas is 10 sccm. The anode voltage of the ion source is 150V, the anode current is 1.2A, argon is used as the working gas, and the flow rate of the argon gas is 100 sccm.

[0061] In the example above using a neutralizer, the ionization of argon gas from the ion source forms near-plasma. However, this plasma may contain excess charged ions. The argon gas in the neutralizer neutralizes these excess charged ions by ionizing into electrons, thereby eliminating the influence of charged ions on the evaporated film and ensuring the quality of each film layer deposited with ion source assistance. This effect can be achieved with only a very small flow ratio of neutralizing gas to working gas (1 / 10 or 1 / 12.5).

[0062] In one example, in steps S4 to S13, the vapor deposition is performed using resistance heating evaporation.

[0063] In one example, the vacuum coating machine in optional step S15 is the same model as the vacuum coating machine in steps S1 to S14. In optional step S15, the temperature of the chamber is set to 130°C, and the vacuum level is reached and maintained at 1.5 × 10⁻⁶. -3Pa, the evaporation process uses resistance heating for evaporation, and the AF film can be, but is not limited to, SH-HT material. The thickness of the AF film is controlled at 80nm ± 3nm. The AF film is used for waterproofing.

[0064] [test]

[0065] Example 1

[0066] The preparation method for depositing a dual-band antireflection film system on a chalcogenide glass substrate includes the following steps:

[0067] S1, the surface of the chalcogenide glass substrate used as the lens and the coating sheet are cleaned by ultrasonic cleaning. The chalcogenide glass substrate is VIG04 substrate and the thickness of the coating sheet is 1.0mm.

[0068] S2, Place the cleaned lens into the fixture, and hang the fixture with the lens in it into the cavity of the vacuum coating machine. The temperature of the cavity is set to 130℃. The vacuum coating machine is a Hall ion source with a neutralizer manufactured and sold by Chengdu Xiwoke Vacuum Technology Co., Ltd. The Hall ion source with a neutralizer was purchased from Boton Optoelectronics Technology Co., Ltd.

[0069] S3, the vacuum coating machine starts pumping vacuum, and the vacuum level reaches 1.5×10. -3 Pa, turn on the ion source of the auxiliary coating of the vacuum coating machine for cleaning. The cleaning time is 6 minutes. The anode voltage of the ion source is 220V, the anode current is 1.2A, and the emitter current is 1.5A. Argon is used as the working gas.

[0070] S4, maintaining the aforementioned vacuum level, deposit a first YF3 film layer on the first surface of the lens by vapor deposition. The deposition rate of the first YF3 film layer is 0.8 nm / s, and the thickness of the first YF3 film layer is controlled to be 70 nm. Ion source assisted vapor deposition is used, and resistance heating evaporation is employed for the vapor deposition.

[0071] S5, deposit a first ZnSe film on the deposited first YF3 film. The deposition rate of the first ZnSe film is 0.8 nm / s, and the thickness of the first ZnSe film is controlled to be 91 nm. Ion source assisted evaporation is used, and resistance heating evaporation is employed for the evaporation.

[0072] S6, a second YF3 film layer is deposited on the first ZnSe film layer. The deposition rate of the second YF3 film layer is 0.8 nm / s, and the thickness of the second YF3 film layer is controlled to be 80 nm. Ion source assisted evaporation is used, and resistance heating evaporation is employed for the evaporation.

[0073] S7, a second ZnSe film is deposited on the deposited second YF3 film. The deposition rate of the second ZnSe film is 0.8 nm / s, and the film thickness of the second ZnSe film is controlled to be 90 nm. Ion source assisted evaporation is used, and resistance heating evaporation is employed for the evaporation.

[0074] S8, a third YF3 film layer is deposited on the deposited second ZnSe film layer. The deposition rate of the third YF3 film layer is 0.8 nm / s, and the film thickness of the third YF3 film layer is controlled to be 83 nm. Ion source assisted evaporation and resistance heating evaporation are used for evaporation.

[0075] S9, a third ZnSe film is deposited on the deposited third YF3 film. The deposition rate of the third ZnSe film is 0.8 nm / s, and the thickness of the third ZnSe film is controlled to be 100 nm. Ion source assisted evaporation is used, and resistance heating evaporation is used for evaporation.

[0076] S10, a fourth YF3 film layer is deposited on the deposited third ZnSe film layer. The deposition rate of the fourth YF3 film layer is 0.8 nm / s, and the film thickness of the fourth YF3 film layer is controlled to be 760 nm. Ion source assisted evaporation is used, and resistance heating evaporation is employed for the evaporation.

[0077] S11, a fourth ZnSe film is deposited on the deposited fourth YF3 film. The deposition rate of the fourth ZnSe film is 0.8 nm / s, and the thickness of the fourth ZnSe film is controlled to be 100 nm. Ion source assisted evaporation is used, and resistance heating evaporation is employed.

[0078] S12, a fifth YF3 film layer is deposited on the deposited fourth ZnSe film layer. The deposition rate of the fifth YF3 film layer is 0.8 nm / s, and the film thickness of the fifth YF3 film layer is controlled to be 126 nm. Ion source assisted evaporation is used, and resistance heating evaporation is used for evaporation.

[0079] S13, a LaF3 film is deposited on the fifth YF3 film layer. The deposition rate of the LaF3 film layer is 0.6 nm / s, and the film thickness of the LaF3 film layer is controlled to be 40 nm. Ion source assisted evaporation is used, and resistance heating evaporation is used for evaporation.

[0080] S14. After the LaF3 film is deposited by vapor deposition, wait for the vacuum chamber to cool to below 90°C and then take out the tooling fixture, along with the substrate and the product.

[0081] Optional step S15 involves depositing an AF film onto the LaF3 film in another vacuum coating machine without using an ion source-assisted deposition. The vacuum coating machine used in optional step S15 is the same model as those used in steps S1 to S14. In optional step S15, the chamber temperature is set to 130°C, and the vacuum level is reached and maintained at 1.5 × 10⁻⁶. -3 Pa, the evaporation is carried out by resistance heating evaporation, the AF film is SH-HT material (commercially purchased from Duen Optics (Changshu) Co., Ltd.), and the film thickness of the AF film is controlled at 80nm;

[0082] S16, repeat steps S1 to S15, and sequentially deposit the first YF3 film, the first ZnSe film, the second YF3 film, the second ZnSe film, the third YF3 film, the third ZnSe film, the fourth YF3 film, the fourth ZnSe film, the fifth YF3 film, the LaF3 film, and the optional AF film on the opposite second side of the lens;

[0083] In steps S4, S6, S8, S10 and S12, a neutralizer is provided for the ion source. The parameters of the neutralizer are: neutralization current of 0.5A, neutralization gas is formed by argon, and the flow rate of the neutralization gas is 8sccm. The anode voltage of the ion source is 180V, the anode current is 2A, argon and oxygen are used as working gases, the flow rate of argon is 20sccm and the flow rate of oxygen is 80sccm.

[0084] In steps S5, S7, S9, S11 and S13, a neutralizer is provided for the ion source. The parameters of the neutralizer are: neutralization current of 0.5A, neutralization gas is formed by argon, and the flow rate of the neutralization gas is 10 sccm. The anode voltage of the ion source is 150V, the anode current is 1.2A, argon is used as the working gas, and the flow rate of the argon gas is 100 sccm.

[0085] For Example 1, there are two cases: step S15 is not executed and step S15 is executed.

[0086] If step S15 is not performed, the chalcogenide glass substrate has ten film layers on one side. Figure 2 It can be seen that the transmittance at 1064nm is 97.42%. Figure 3 It can be seen that the transmittance in the 8-12μm band is 95.58%.

[0087] When step S15 is performed, there are eleven film layers on one side of the chalcogenide glass substrate. When the AF film layer is deposited in step S15, from... Figure 4 It can be seen that the transmittance at 1064nm is 96.27%. Figure 5 It can be seen that the transmittance in the 8-12μm band is 95.12%.

[0088] This demonstrates that the chalcogenide glass substrate and the antireflective coatings on both surfaces can meet the dual-band transmittance requirements. Furthermore, when step S15 is performed, the AF film layer also provides waterproofing.

[0089] The performance of the substrate and the antireflection coating system on both sides is tested (both cases are tested: step S15 is not performed and step S15 is performed).

[0090] Water immersion test: The substrate prepared in Example 1, together with the antireflective coatings deposited on both sides, was subjected to a water immersion test with tap water for 10 minutes. No film layer was found to detach from the substrate or to crack on any side.

[0091] Adhesion test: After the immersion and salt spray tests using tap water, 3M tape was applied to the outermost layer of each side of the coated sheet by hand and pulled in the opposite direction to the adhesive end. The outermost layer was not pulled up.

[0092] The water immersion test and the tape pull test showed that the antireflective coating system on both sides of the substrate had good adhesion.

[0093] Constant temperature and humidity test: 48 hours at 50℃ and 95% relative humidity in a constant temperature and humidity chamber. No film peeling or cracking was observed on any surface of the substrate.

[0094] 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 dual-band antireflection film system deposited on a chalcogenide glass substrate, characterized in that, Including the following steps: S1, the surface of the coating sheet and the product, which serve as the chalcogenide glass substrate for the lens, are cleaned. The chalcogenide glass substrate is a VIG04 substrate, and the thickness of the coating sheet is 0.9-1.5mm. S2, Place the cleaned lens into the fixture, and hang the fixture with the lens in it into the cavity of the vacuum coating machine. The temperature of the cavity is set to 130℃. S3, the vacuum coating machine starts pumping vacuum, and the vacuum level reaches 1.5×10. -3 Pa, turn on the ion source of the auxiliary coating of the vacuum coating machine for cleaning. The cleaning time is 6 minutes. The anode voltage of the ion source is 220V, the anode current is 1.0-2.5A, and the emitter current is 1.3-1.5A. S4, maintaining the aforementioned vacuum level, deposit a first YF3 film layer on the first surface of the lens by evaporation. The deposition rate of the first YF3 film layer is 0.8 nm / s, and the film thickness of the first YF3 film layer is controlled to be 70 nm ± 3 nm. Ion source assisted evaporation. S5, deposit a first ZnSe film on the deposited first YF3 film. The deposition rate of the first ZnSe film is 0.8 nm / s, and the thickness of the first ZnSe film is controlled to be 91 nm ± 3 nm. Ion source assisted evaporation. S6, a second YF3 film layer is deposited on the first ZnSe film layer. The deposition rate of the second YF3 film layer is 0.8 nm / s, and the film thickness of the second YF3 film layer is controlled to be 80 nm ± 3 nm. Ion source assisted evaporation. S7, a second ZnSe film is deposited on the deposited second YF3 film. The deposition rate of the second ZnSe film is 0.8 nm / s, and the thickness of the second ZnSe film is controlled to be 90 nm ± 3 nm. Ion source assisted evaporation. S8, a third YF3 film is deposited on the deposited second ZnSe film. The deposition rate of the third YF3 film is 0.8 nm / s, and the thickness of the third YF3 film is controlled to be 83 nm ± 3 nm. Ion source assisted evaporation. S9, a third ZnSe film is deposited on the deposited third YF3 film. The deposition rate of the third ZnSe film is 0.8 nm / s, and the thickness of the third ZnSe film is controlled to be 100 nm ± 4 nm. Ion source assisted evaporation. S10, a fourth YF3 film layer is deposited on the deposited third ZnSe film layer. The deposition rate of the fourth YF3 film layer is 0.8 nm / s, and the film thickness of the fourth YF3 film layer is controlled to be 760 nm ± 5 nm. Ion source assisted evaporation. S11, a fourth ZnSe film is deposited on the deposited fourth YF3 film. The deposition rate of the fourth ZnSe film is 0.8 nm / s, and the thickness of the fourth ZnSe film is controlled to be 100 nm ± 4 nm. Ion source assisted evaporation. S12, a fifth YF3 film layer is deposited on the deposited fourth ZnSe film layer. The deposition rate of the fifth YF3 film layer is 0.8 nm / s, and the film thickness of the fifth YF3 film layer is controlled to be 126 nm ± 4 nm. Ion source assisted evaporation. S13, a LaF3 film is deposited on the fifth YF3 film layer. The deposition rate of the LaF3 film layer is 0.6 nm / s, and the film thickness of the LaF3 film layer is controlled to be 40 nm ± 2 nm. Ion source assisted evaporation. S14. After the LaF3 film is deposited by vapor deposition, wait for the vacuum chamber to cool to below 90°C and then take out the tooling fixture, along with the substrate and the product. S16, repeat steps S1 to S14, and sequentially deposit the first YF3 film, the first ZnSe film, the second YF3 film, the second ZnSe film, the third YF3 film, the third ZnSe film, the fourth YF3 film, the fourth ZnSe film, the fifth YF3 film, and the LaF3 film on the opposite second side of the lens. Based on the tests of the 1064nm band and 8-12μm band of the substrate, the transmittance of the 1064nm band is 97.42%, and the transmittance of the 8-12μm band is 95.58%.

2. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In step S1, the thickness of the substrate is 1.0 mm.

3. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In step S1, the lens surface is cleaned using ultrasound or by hand.

4. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In step S3, the anode current is 1.2A and the emitter current is 1.5A.

5. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In step S3, the ion source is a Hall ion source.

6. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In step S4, the thickness of the first YF3 film is controlled to be 70 nm; In step S5, the thickness of the first ZnSe film is controlled to be 91 nm; In step S6, the thickness of the second YF3 film is controlled to be 80 nm; In step S7, the thickness of the second ZnSe film is controlled to be 90 nm; In step S8, the thickness of the third YF3 film is controlled to be 83 nm; In step S9, the thickness of the third ZnSe film is controlled to be 100 nm; In step S10, the thickness of the fourth YF3 film is controlled to be 760 nm; In step S11, the thickness of the fourth ZnSe film is controlled to be 100 nm; In step S12, the thickness of the fifth YF3 film is controlled to be 126 nm; In step S13, the thickness of the LaF3 film is controlled to be 40 nm.

7. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In steps S4, S6, S8, S10 and S12, a neutralizer is provided for the ion source. The parameters of the neutralizer are: neutralization current of 0.5A, neutralization gas is formed by argon, and the flow rate of the neutralization gas is 8 sccm. The anode voltage of the ion source is 180V, the anode current is 2A, argon and oxygen are used as working gases, the flow rate of argon is 20 sccm and the flow rate of oxygen is 80 sccm.

8. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In steps S5, S7, S9, S11 and S13, a neutralizer is provided for the ion source. The parameters of the neutralizer are: neutralization current of 0.5A, neutralization gas is formed by argon, and the flow rate of the neutralization gas is 10 sccm. The anode voltage of the ion source is 150V, the anode current is 1.2A, argon is used as the working gas, and the flow rate of the argon gas is 100 sccm.

9. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, In steps S4 to S13, the vapor deposition is performed using resistance heating evaporation.

10. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 1, characterized in that, The method for preparing a dual-band antireflection coating system deposited on a chalcogenide glass substrate further includes the step: S15, depositing an AF film layer on the deposited LaF3 film layer in another vacuum coating machine without using an ion source to assist in the evaporation. Step S16 is replaced by: repeating steps S1 to S15, and sequentially depositing the first YF3 film, the first ZnSe film, the second YF3 film, the second ZnSe film, the third YF3 film, the third ZnSe film, the fourth YF3 film, the fourth ZnSe film, the fifth YF3 film, the LaF3 film, and the AF film on the opposite second side of the lens; Based on the tests of the 1064nm band and 8-12μm band of the coated film, the transmittance of the 1064nm band is 96.27%, and the transmittance of the 8-12μm band is 95.12%.

11. The method for preparing a dual-band antireflection film system deposited on a chalcogenide glass substrate according to claim 10, characterized in that, The vacuum coating machine in step S15 is the same model as the vacuum coating machines in steps S1 to S14. In step S15, the temperature of the cavity is set to 130°C, and the vacuum level is reached and maintained at 1.5 × 10⁻⁶. -3 Pa, the vapor deposition is carried out by resistance heating evaporation, the AF film is made of SH-HT material, and the film thickness of the AF film is controlled at 80nm±3nm.

Images