A semi-reflective, semi-transparent automotive rearview mirror lens and its preparation method

Abstract

This invention relates to the field of automotive parts technology, and particularly to a semi-reflective rearview mirror lens and its manufacturing method. The semi-reflective rearview mirror lens includes a glass substrate, at least one anti-reflective layer and at least one anti-reflective layer formed on both sides of the glass substrate, and a third high-refractive-index layer formed on the surface of the anti-reflective layer. The anti-reflective layer comprises a high-refractive-index layer and a low-refractive-index layer stacked sequentially, with the third high-refractive-index layer formed on the surface of the low-refractive-index layer. The refractive indices of the high-refractive-index layer and the third high-refractive-index layer are 2.20–2.72; the refractive index of the low-refractive-index layer is 1.46–1.80. The semi-reflective rearview mirror lens provided by this invention can effectively improve the visible light reflectivity of the rearview mirror while avoiding image color distortion.

Description

Technical Field

[0001] This invention relates to the field of automotive parts technology, and in particular to a semi-reflective, semi-transparent automotive rearview mirror lens and its manufacturing method. Background Technology

[0002] The rearview mirror inside the driver's cabin is mainly used by the driver to observe and understand the situation behind the vehicle, as well as to observe the situation of the passengers behind the driver. Its structure and construction have been repeatedly improved, evolving from a simple plane mirror to a technical structure that integrates an electronic display screen embedded in the rearview mirror, and optical lenses connected by wires to a camera mounted at the rear of the vehicle, as well as wireless video.

[0003] Most rearview mirrors use semi-reflective mirrors, meaning they have 50% reflectivity and 50% transmittance of visible light. However, these mirrors suffer from insufficient reflectivity. To improve the reflectivity of interior rearview mirrors, Chinese patent CN209619202U uses a Nb2O5 / SiO2 / Nb2O5 / SiO2 / Nb2O5 / SiO2 anti-reflective layer structure. While this structure enhances reflectivity, it introduces image blurring due to ghosting. Furthermore, it fails to address color distortion (bluish tint) and reddish tint in the transmitted color (reddish tint in the displayed area), posing a safety hazard. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a semi-reflective and semi-transparent automotive rearview mirror lens that can effectively avoid visual distortion and its preparation method.

[0005] To solve the above-mentioned technical problems, the present invention provides a semi-reflective and semi-transparent automotive rearview mirror lens, comprising a glass substrate, at least one anti-reflection layer and at least one anti-reflection layer formed on both sides of the glass substrate, and a third high refractive index layer formed on the surface of the anti-reflection layer.

[0006] The antireflective layer comprises a high refractive index layer and a low refractive index layer stacked sequentially, and the third high refractive index layer is formed on the surface of the low refractive index layer;

[0007] The refractive indices of the high refractive index layer and the third high refractive index layer are 2.20 to 2.72;

[0008] The refractive index of the low-refractive-index layer is 1.46 to 1.80.

[0009] A method for preparing a semi-reflective and semi-transparent automotive rearview mirror lens is further provided, including the steps of forming an anti-reflection layer and an anti-reflection layer on both sides of a glass substrate by magnetron sputtering.

[0010] And the step of magnetron sputtering a third high-refractive-index layer on the surface of the antireflective layer;

[0011] The antireflective layer comprises a high refractive index layer and a low refractive index layer stacked sequentially, and the third high refractive index layer is formed on the surface of the low refractive index layer;

[0012] The refractive indices of the high refractive index layer and the third high refractive index layer are 2.20 to 2.72;

[0013] The refractive index of the low-refractive-index layer is 1.46 to 1.80.

[0014] The beneficial effects of the present invention are as follows: The present invention improves the visible light reflectivity of the rearview mirror by rationally designing the semi-reflective and semi-transparent film layer structure on the inner surface of the rearview mirror lens, while using an anti-reflective film deposited on the outer surface of the rearview mirror lens to achieve clear images without ghosting and natural and undistorted colors, thereby effectively improving the safety of vehicle driving. Attached Figure Description

[0015] Figure 1 The diagram shown is an optical path diagram of a conventional automotive rearview mirror lens with a semi-reflective and semi-transparent film in a specific embodiment of the present invention.

[0016] Figure 2 The diagram shows the optical path of forming an anti-reflective film on the surface of an existing automotive rearview mirror lens with a semi-reflective and semi-transparent film, according to a specific embodiment of the present invention.

[0017] Figure 3 The image shown is a morphological photograph and a table of related component analysis of TiO2 films deposited by HiPIMS power supply and MF power supply in a specific embodiment of the present invention.

[0018] Figure 4 The diagram shown is a structural schematic of a semi-reflective, semi-transparent automotive rearview mirror lens in a specific embodiment of the present invention.

[0019] Figure 5 The diagram shown is another structural schematic of a semi-reflective, semi-transparent automotive rearview mirror lens in a specific embodiment of the present invention.

[0020] Label Explanation:

[0021] exist Figure 1 and Figure 2 In the middle: 11. Light source; 22, 31, 42. Refracted rays; 21, 32. Reflected rays; 4. Semi-reflective film; 5. Glass substrate; 6. Anti-reflective film;

[0022] exist Figure 4In the middle: 1. Glass substrate; 2. First antireflective layer; 3. Second antireflective layer; 4. Third high refractive index layer; 5. First antireflective layer; 6. Second antireflective layer;

[0023] exist Figure 5 In the middle: 11, glass substrate; 21, first high refractive index layer; 22, first low refractive index layer; 31, second high refractive index layer; 32, second low refractive index layer; 41, third high refractive index layer; 51, fourth high refractive index layer; 52, fourth high refractive index layer; 61, fifth high refractive index layer; 62, fifth low refractive index layer. Detailed Implementation

[0024] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0025] A semi-reflective, semi-transparent automotive rearview mirror lens includes a glass substrate, at least one anti-reflective layer and at least one anti-reflective layer formed on both sides of the glass substrate, and a third high-refractive-index layer formed on the surface of the anti-reflective layer; wherein the anti-reflective layer includes a high-refractive-index layer and a low-refractive-index layer formed sequentially, and the third high-refractive-index layer is formed on the surface of the low-refractive-index layer; the refractive indices of the high-refractive-index layer and the third high-refractive-index layer are 2.20 to 2.72; and the refractive index of the low-refractive-index layer is 1.46 to 1.80.

[0026] Specifically, by utilizing a specific combination of high-refractive-index and low-refractive-index layers, the reflectivity of the anti-reflective layer can be adjusted, and combined with an anti-reflective layer, issues such as image ghosting and color distortion can be improved. In particular, to address existing defects in smart rearview mirrors on the market, current technology deposits a semi-reflective, semi-transparent film on the back side of the glass substrate (the side facing away from the incident light), with the structure as follows: Figure 1As shown. The semi-reflective and semi-transparent film 4 is located inside the rearview mirror, specifically between the display screen and the glass substrate 5. When the human eye observes the rear view through the rearview mirror, there is a certain angle (horizontal / vertical angle) between the eye and the mirror. The rear light source 11 (100%) is incident from the air onto the glass interface, generating reflected light 21 and refracted light 22. Only about 4% of the reflected light 21 enters the human eye. Since the overall thickness of the film layer (semi-reflective and semi-transparent film 4) is too thin, the reflection and refraction of refracted light 22 within the film layer 4 can be temporarily disregarded. At this time, refracted light 22 also generates reflected light 32 and refracted light 31 from the glass / film layer and air interface. Since the film layer is designed to have semi-reflective and semi-transparent properties, the refracted light 31 is approximately 50%, and the reflected light 32 is approximately 46%. Reflected light 32 is reflected off the glass substrate 5, generating reflected light again at the glass / air interface (shown by the dashed line in the figure, which can be disregarded due to its small quantity) and refracted light 42 (approximately 42%). Refracted light 42 can enter the human eye. Therefore, since the secondary image (4%) formed by reflected light 21 and the primary image (approximately 46%) formed by refracted light 42 enter the eye simultaneously, their brightness ratio is relatively high, resulting in image blurring in the human eye. Furthermore, the brightness ratio increases with the viewing angle. Similarly, the image displayed on the rearview mirror's back screen also becomes blurry in the human eye.

[0027] Based on existing technology, this invention deposits an anti-reflective film on the front side of a glass substrate, the structure of which is as follows: Figure 2 As shown in the figure, the antireflective coating 6 can significantly reduce the brightness of the secondary image and enhance the brightness of the primary image. Therefore, the brightness ratio between the secondary image (0.5%) formed by reflected light 21 and the primary image (approximately 49.5%) formed by refracted light 42 is reduced, thereby achieving an augmented reality effect and avoiding ghosting. Specific data are shown in Table 1.

[0028] Table 1

[0029] Secondary image reflectance (%) 0° 15° 30° 45° 60° 3.5mm ultra-clear glass 4.4 4.4 4.5 5.1 8.1 3.5mm ultra-clear glass + anti-reflective coating 0.3 0.3 0.4 1.3 5

[0030] As can be seen from Table 1, the anti-reflection film can effectively reduce the reflectivity of the secondary image while improving the brightness of the primary image. Therefore, by depositing an anti-reflection film on the outer surface of the glass substrate, the brightness ratio between the secondary image and the primary image can be reduced, thereby avoiding the occurrence of ghosting.

[0031] Since the brightness of existing displays can be adjusted, the reflectivity of the semi-reflective film (i.e., the combination of the anti-reflective layer and the third high-refractive-index layer described herein) can be improved through film layer design, thereby obtaining a brighter field of view and clearer information about the rear of the vehicle in the rearview mirror. For example, see the comparison between Comparative Example 1 and Example 6 below. Comparative Example 1 uses Si3N4 (n=2.13) as the high-refractive-index layer material, with a visible light reflectivity of only 46.4%, while Example 6 uses TiO2 (n=2.70) as the high-refractive-index material, thereby increasing the reflectivity to 80.1%. This effectively improves the clarity of the rear view and the interior view within the vehicle in the rearview mirror.

[0032] High-quality, high-refractive-index TiO2 films are difficult to prepare using magnetron sputtering with a magnetic flux (MF) power supply. Specifically, TiO2 has three crystal structures: brookite TiO2, rutile TiO2, and anatase TiO2. Among these, the brookite type is the most difficult to synthesize. The rutile type exhibits higher stability and, compared to anatase, higher refractive index, relative density, and dielectric constant. The anatase type is a metastable phase; with increasing heating temperature, the TiO2 film undergoes a microstructural transformation from amorphous to anatase, then to a mixed anatase and rutile phase, and finally back to rutile. According to existing literature, the heating temperature required for the complete transformation of TiO2 films to the rutile state needs to reach above 1000℃. However, TiO2 films deposited by conventional MF power supplies often fail to fully transform into rutile structures after heating and annealing (600–790°C) due to insufficient heating temperature. Consequently, the refractive index n after annealing is generally limited to n ≤ 2.50, making it difficult to prepare films with refractive indices greater than 2.50. Furthermore, TiO2 films deposited by conventional MF power supply magnetron sputtering contain fewer ions and have lower ionization rates. While vacuum cathode arc deposition can produce high particle ionization rates, it generates large metal / metal compound particles, resulting in excessive coating impurities, and requires increased cooling when the cathode overheats, making it unsuitable for the automotive glass coating industry. In contrast, HiPIMS power supplies, with their high pulse peak power and low pulse duty cycle, and the lack of additional cathode cooling requirements while maintaining high ionization rates, are suitable for the automotive glass coating industry. The relevant comparative parameters of HiPIMS (High Power Pulsed Magnetron Sputtering) power supplies and MF power supplies are shown in Table 2.

[0033] Table 2

[0034] MF HiPIMS Operating power (non-average power) <120kW 100kW~2MW Peak power <![CDATA[10W / cm 2 Level <![CDATA[1~3KW / cm 2 Level Current density <![CDATA[10mA / cm 2 Level <![CDATA[1~5A / cm 2 Level Duty cycle 100％ 1％～15％ Operating voltage 0～800V 0～2000V Operating current 0～200A 0～1000A Ionization rate 30％～40％ Maximum >80% Film adhesion force weak powerful

[0035] Meanwhile, preliminary experiments have demonstrated that the TiO2 film deposited using the HiPIMS power source possesses a rutile structure, as shown in Table 3. Figure 3 As shown.

[0036] Table 3

[0037]

[0038]

[0039] Therefore, by adjusting the power supply parameters of HiPIMS, a TiO2 film with a refractive index n of 2.50–2.72 after heat annealing can be obtained. Furthermore, thanks to TiO2… x The high ionization rate of the membrane layer, the antireflective membrane system during heating and annealing, TiO x The film can be transformed more towards the rutile structure.

[0040] In a method for preparing TiO₂ with a refractive index n of 2.50–2.72 x In the implementation of the single-film layer, the process parameters are shown in Table 4.

[0041] Table 4

[0042] Serial Number project parameter 1 power supply HiPIMS Power Supply 2 Target material <![CDATA[TiO x Target material, where 1.8 ≤ x ≤ 1.9 3 Process Gases <![CDATA[Ar, O2; the flow rate of O2 is 0 to 30 sccm]]> 4 Pulse peak power 100kW~2000kW 5 Pulse current 300A~1000A 6 pulse voltage 300V~2000V 7 Duty cycle 1％～15％ 8 Pulse width 0~150μs

[0043] While this combination of two layers (anti-reflective layer and semi-reflective / semi-transparent film) effectively avoids ghosting, the different color systems of each layer can easily lead to interference, resulting in changes in displayed colors. Therefore, this invention addresses this by rationally designing the layers of the semi-reflective / semi-transparent film to ensure that the anti-reflective and semi-reflective film systems do not interfere with each other. This allows the rearview mirror lens to function as a semi-reflective / semi-transparent lens while also ensuring clear, ghost-free images through the anti-reflective film. Simultaneously, the rational design of the semi-reflective / semi-transparent film system eliminates the color changes caused by the different color systems of the two layers. The rational design of the semi-reflective / semi-transparent film system mainly involves adjusting the refractive index and selecting the film thickness. The film thickness is a crucial characteristic determining color cast in the field of view. Referring to Comparative Example 2 and Example 3 below, it can be seen from the data that although Comparative Example 2 used TiO2 (n=2.50) as the high refractive index layer material, achieving a reflectivity of 65.2% for the rearview mirror, the film system design was unreasonable. The thicknesses of the first high refractive index layer 21, the first low refractive index layer 22, and the second low refractive index layer 32 all exceeded the reasonable range. This resulted in a Lab value of 3.4 and a b value of -5.4 for the color reflected by the rearview mirror when visible light was incident at a 30° angle, with the overall reflected color leaning towards reddish-purple. In other words, a reddish-purple filter existed in the rear view at a 30° angle, causing severe distortion of the field of view. In contrast, Example 3, through a reasonable design of the film system, controlled the thickness of each layer within a reasonable range. When visible light was incident at a 30° angle, the Lab values ​​of the color reflected by the rearview mirror were close to neutral for both a and b, ensuring a true and undistorted image of the rear view in the rearview mirror.

[0044] In one implementation, see Figure 4 As shown, the semi-reflective rearview mirror lens includes two stacked anti-reflective layers, namely a first anti-reflective layer 2 and a second anti-reflective layer 3. The two anti-reflective layers are located between the glass substrate 1 and the third high refractive index layer 4. The anti-reflective layer is composed of at least one high refractive index layer and at least one low refractive index layer.

[0045] In another implementation, see Figure 5 As shown, the antireflective layer includes a first high refractive index layer 21, a first low refractive index layer 22, a second high refractive index layer 31, and a second low refractive index layer 32, which are sequentially stacked on the surface of the glass substrate 1.

[0046] The materials of the first high refractive index layer, the second high refractive index layer, and the third high refractive index layer are selected from ZrO. x NbO x At least one of the following: TiO2 film deposited using an MF power supply or a HiPIMS power supply, wherein 1 < x ≤ 3. That is, in this embodiment, a TiO2 film with a refractive index n greater than 2.50, preferably 2.50 to 2.72, can be deposited using a HiPIMS power supply magnetron sputtering.

[0047] It should be noted that, for ease of writing, the term TiO2 film is used to refer to the film formed by MF or HiPIMS power sources in this article. However, for TiO2 film formed by HiPIMS power sources, the material should be understood as TiOx, where 1.8 ≤ X ≤ 2.

[0048] In a preferred embodiment, the thickness of the first high refractive index layer is 70–120 nm.

[0049] In a preferred embodiment, the thickness of the second high refractive index layer is 35–75 nm.

[0050] In a preferred embodiment, the thickness of the third high refractive index layer is 20–65 nm.

[0051] In one embodiment, the materials of the first low-refractive-index layer and the second low-refractive-index layer are selected from SiO2. x SiBO x SiTiO x SiAlO x SiZrO x SiN x O y SiBN x O y SiTiN xO y SiAlN x O y SiZrN x O y At least one of the following, where 1 < x ≤ 3 and 1 < y < 3.

[0052] In a preferred embodiment, the thickness of the first low-refractive-index layer is 60–150 nm.

[0053] In a preferred embodiment, the thickness of the second low-refractive-index layer is 65–110 nm.

[0054] In one embodiment, the antireflective layer comprises a fourth high refractive index layer, a fourth low refractive index layer, a fifth high refractive index layer, and a fifth low refractive index layer sequentially stacked on the surface of the glass substrate; wherein the refractive indices of the fourth high refractive index layer and the fifth high refractive index layer are 1.90 to 2.72; and the refractive indices of the fourth low refractive index layer and the fifth low refractive index layer are 1.46 to 1.60.

[0055] The materials of the fourth high refractive index layer and the fifth high refractive index layer are selected from SiN. x SiAlN x SiBN x SiTiN x SiZrN x ZnAlO x ZnO x ZnSnO x NbO x ZrO x At least one of the following: TiO2 film deposited using MF power supply or HiPIMS, wherein 1 < x < 3.

[0056] In a preferred embodiment, the thickness of the fourth high refractive index layer is 5–30 nm.

[0057] In a preferred embodiment, the thickness of the fifth high refractive index layer is 15–45 nm.

[0058] In one embodiment, the materials of the fourth and fifth low-refractive-index layers are selected from SiO2. x SiBO x SiTiO x SiAlO x SiZrO x At least one of them, where 1 < x < 3.

[0059] In a preferred embodiment, the thickness of the fourth low-refractive-index layer is 30–55 nm.

[0060] In a preferred embodiment, the thickness of the fifth low-refractive-index layer is 85–120 nm.

[0061] Preferably, in the Lab value of the visible light reflection color of the semi-reflective and semi-transparent automotive rearview mirror lens, the value of a is: -1≤a≤1; the value of b is: -1≤b≤1; and the visible light reflectance R is: 60≤R≤85.

[0062] Preferably, the Lab value of the visible light transmission color of the semi-reflective and semi-transparent automotive rearview mirror lens has an a value of a≤2; and the visible light transmittance T has a value of 15≤T≤40.

[0063] A method for fabricating a semi-reflective, semi-transparent automotive rearview mirror lens includes the steps of forming an anti-reflection layer and an anti-reflection layer on both sides of a glass substrate by magnetron sputtering; and the step of magnetron sputtering a third high-refractive-index layer on the surface of the anti-reflection layer; wherein the anti-reflection layer comprises a high-refractive-index layer and a low-refractive-index layer formed sequentially, and the third high-refractive-index layer is formed on the surface of the low-refractive-index layer; the refractive indices of the high-refractive-index layer and the third high-refractive-index layer are 2.20 to 2.72; and the refractive index of the low-refractive-index layer is 1.46 to 1.80.

[0064] In one embodiment, the antireflective layer includes a first high refractive index layer 21, a first low refractive index layer 22, a second high refractive index layer 31, and a second low refractive index layer 32, which are sequentially stacked.

[0065] The materials of the first high refractive index layer, the second high refractive index layer, and the third high refractive index layer are selected from ZrO. x NbO x At least one of the following: TiO2 films deposited using an MF power supply or a HiPIMS power supply, wherein 1 < x ≤ 3.

[0066] In one embodiment, the preparation method further includes a step of heating and annealing the coated lens. The heating and annealing can employ any existing high-temperature annealing process, such as tempering or semi-tempered tempering. In an exemplary embodiment, semi-tempered tempering technology is used, with the following parameters (based on the heating air temperature): Heating process: preheating temperature 570℃, preheating time 240s; heating temperature 690℃, heating time 240s; annealing temperature 300℃, annealing time 240s.

[0067] Preparation example (taking Example 3 as an example)

[0068] See Figure 5 As shown, a method for preparing a semi-reflective, semi-transparent automotive rearview mirror lens includes the following steps:

[0069] S1. After washing and drying, float ultra-white flat glass with a thickness of 3.5mm enters the magnetron sputtering coating line to deposit an anti-reflection coating layer.

[0070] S2, Magnetron sputtering of the fourth high refractive index layer 51: TiO2, with the following parameters:

[0071] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0072] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:30;

[0073] Sputtering pressure 2.8E -3 mbar; coating thickness is 16.1 nm;

[0074] S3, magnetron sputtering of the fourth low emissivity layer 52: SiO2, with the following parameters:

[0075] Number of targets: 2 dual rotating cathodes; Power supply for targets: MF (medium frequency power supply);

[0076] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0077] Sputtering pressure 3.5E -3 mbar; coating thickness is 40.7nm;

[0078] S4, Magnetron sputtering of the fifth high-refractive-index layer 61: TiO2, with the following parameters:

[0079] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0080] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:30;

[0081] Sputtering pressure 2.8E -3 mbar; coating thickness is 24.1 nm;

[0082] S5, magnetron sputtering of the fifth low-refractive-index layer 62: SiO2, with the following parameters:

[0083] Number of targets: 4 dual rotating cathodes; Target power supply: MF (medium frequency power supply);

[0084] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0085] Sputtering pressure 3.4E-3 mbar; coating thickness is 104nm;

[0086] S6. After the coating is completed, optical testing and quality inspection are carried out on the anti-reflection film. After the optical testing is completed, the film is sent to the powder spraying machine for powder spraying and then collected.

[0087] S7. After a package is full, it is transported to the film placement area of ​​the coating line and rotated using a crane. After washing and drying, it enters the magnetron sputtering coating line to deposit a semi-reflective and semi-transparent film layer.

[0088] S8, First high refractive index layer 21: TiO2, sputtered by magnetron sputtering, with the following parameters:

[0089] Number of targets: 2 dual rotating cathodes; Power supply for targets: MF (medium frequency power supply);

[0090] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:30;

[0091] Sputtering pressure 2.8E -3 mbar; coating thickness is 95.7nm;

[0092] S9, First low emissivity layer 22: SiO2, sputtered by magnetron sputtering, with the following parameters:

[0093] Number of targets: 4 dual rotating cathodes; Target power supply: MF (medium frequency power supply);

[0094] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0095] Sputtering pressure 3.4E -3 mbar; coating thickness is 88.4 nm;

[0096] S10, magnetron sputtering of the second high refractive index layer 31: TiO2, with the following parameters:

[0097] Number of targets: 2 dual rotating cathodes; Power supply for targets: MF (medium frequency power supply);

[0098] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:30;

[0099] Sputtering pressure 2.8E -3 mbar; coating thickness is 58.4 nm;

[0100] S11, magnetron sputtering of the second low-refractive-index layer 32: SiO2, with the following parameters:

[0101] Number of targets: 4 dual rotating cathodes; Target power supply: MF (medium frequency power supply);

[0102] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0103] Sputtering pressure 3.4E -3 mbar; coating thickness is 97.3 nm;

[0104] S12, magnetron sputtering of the third high refractive index layer 41: TiO2, with the following parameters:

[0105] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0106] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:30;

[0107] Sputtering pressure 2.8E -3 mbar; coating thickness is 33.3 nm;

[0108] S13. After the coating is completed, the overall film layer is subjected to optical testing and quality inspection. After the optical testing is completed, it is transferred to the powder spraying machine for powder spraying and the film is collected. After a full package is collected, it is transported to the cutting process.

[0109] S14. After cutting the coated sheet into small rectangular pieces using a glass cutting machine, the glass is then cut into the size of the rearview mirror drawing and ground by a CNC machining center. The coated sheet is cleaned with pure water and a brush to remove dirt from its surface, and then dried to provide a clean condition for the next glass semi-steel process, so as to avoid problems such as spots and distortion on the mirror surface.

[0110] S15. The cleaned coated sheet is heated and annealed in a tempering furnace. The specific parameters are as follows (based on the heating air temperature): Heating process: preheating temperature 570℃, preheating time 240s; heating temperature 690℃, heating time 240s; annealing temperature 300℃, annealing time 240s.

[0111] S16. The lens is tested for dimensional stability and coating effect (excluding lenses with surface defects such as scratches, pits, distortion, and edge breakage). After the final inspection, a car interior rearview mirror lens that can be produced is obtained.

[0112] Examples 1 to 12 and Comparative Examples 1 and 2

[0113] The rearview mirror lens for automobiles was prepared according to Tables 5 and 10 below (including film material and corresponding thickness data) and in conjunction with the aforementioned preparation example. The results are shown in Tables 8 and 10, respectively.

[0114] The optical data were measured using an Agilent Cary 7000 angle colorimeter, and the color characterization system used was the CIELab color system.

[0115] It should be noted that in Table 7, the fifth, fourth, first, second, and third high-refractive-index layers in Example 3 are all TiO2 films formed by magnetron sputtering using an MF power supply; the fifth and fourth high-refractive-index layers in Example 4 are both TiO2 films formed by magnetron sputtering using an MF power supply; the fifth and fourth high-refractive-index layers in Example 5 are both TiO2 films formed by magnetron sputtering using an MF power supply; and the fifth and fourth high-refractive-index layers in Example 6 are both TiO2 films formed by magnetron sputtering using an MF power supply. The remaining TiO2 films are all TiO2 films formed by magnetron sputtering using a HiPIMS power supply. Unless otherwise specified, the refractive index of the TiO2 films formed by magnetron sputtering using an MF power supply in Tables 7 and 8 is 2.50.

[0116] Unless otherwise specified, ultra-clear glass will be used as the glass substrate in the following text.

[0117] Table 5

[0118]

[0119]

[0120] Table 6

[0121]

[0122]

[0123] Table 7

[0124]

[0125]

[0126] Table 8

[0127]

[0128] Comparing Examples 1-6 with Comparative Example 1, it can be seen that after adding an anti-reflective coating to the outer surface of the rearview mirror lens in Examples 1-6, there is no ghosting in the rear view and the displayed image, and the image is clear and realistic, thus improving vehicle driving safety. Comparative Example 1 uses Si3N4 (n=2.13) as the high refractive index layer material, and the reflectivity of the rearview mirror lens is only 46.4%. Examples 1-6 use ZrO... xUsing Nb2O5 (n=2.24), TiO2 (n=2.38), TiO2 (n=2.50), TiO2(HiPIMS-n=2.61), TiO2(HiPIMS-n=2.64), and TiO2(HiPIMS-n=2.70) as the first, second, and third high refractive index layers, respectively, the reflectivity of the rearview mirror lens is 60.6%, 71.8%, 72.7%, 78.1%, 79.1%, and 80.1%, respectively, which greatly improves the reflectivity of the rearview mirror lens.

[0129] Through reasonable film system design, Examples 1-6 demonstrate that when visible light is incident at angles of 0° to 30°, the a and b values ​​of the Lab value of the visible light reflection color remain within the neutral color range, ensuring no color distortion in the rearview mirror's reflection of the vehicle's rear. Simultaneously, the a value of the Lab value of the visible light transmission color is within the range of -1 < a ≤ 2, indicating that its transmission color is neutral, and the image displayed on the electronic screen is free of ghosting and color distortion.

[0130] Examples 1-6 involve depositing a visible light anti-reflection layer on the outer surface of the rearview mirror and using a high refractive index material, ZrO. x Using high refractive index layers such as (n=2.24), Nb2O5 (n=2.38), TiO2 (n=2.50), TiO2(HiPIMS-n=2.61), TiO2(HiPIMS-n=2.64), and TiO2(HiPIMS-n=2.70) as a reasonable film system design, the visible light reflectivity of the car rearview mirror is improved, making the image behind the rearview mirror and the image displayed on the electronic display screen clear and without ghosting, with natural and undistorted colors, thus improving the safety of vehicle driving.

[0131] Table 9

[0132]

[0133]

[0134] Table 10

[0135]

[0136] As can be seen from the data in the table above, although Comparative Example 2 used TiO2 (n=2.50) as the high refractive index layer material, achieving a rearview mirror reflectivity of 65.2%, the film system design was unreasonable. The thicknesses of the first high refractive index layer 21, the first low refractive index layer 22, and the second low refractive index layer 32 all exceeded the reasonable film system range. As a result, when visible light is incident at a 30° angle, the Lab value of the visible light reflected by the rearview mirror has an a value of 3.4 and a b value of -5.4, and the overall reflected color is reddish-purple. That is, the rearview mirror reflects the rear view at a 30° angle with a reddish-purple filter, resulting in a distorted view.

[0137] In Examples 7-12, through reasonable film system design, when visible light is incident at an angle of 0-30°, the a and b values ​​of the Lab value of the visible light reflected by the rearview mirror are both neutral, which improves the visible light reflectivity of the car rearview mirror. This makes the images in the rear view of the rearview mirror and the images displayed on the electronic display screen clear and without ghosting, with natural and unbiased colors, thus improving the safety of vehicle driving.

[0138] In summary, this invention deposits an anti-reflective film on the outer surface of the rearview mirror lens and improves the visible light reflectivity of the rearview mirror by rationally designing a semi-reflective and semi-transparent film layer on the inner surface of the rearview mirror lens. This ensures that the images in the rear view of the rearview mirror and the images displayed on the electronic display screen are clear and free of ghosting, with natural and undistorted colors, thereby improving the safety of vehicle driving.

[0139] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A semi-reflective, semi-transparent automotive rearview mirror lens, characterized in that, It includes a glass substrate, at least one antireflection layer and at least one antireflection layer formed on both sides of the glass substrate, and a third high refractive index layer formed on the surface of the antireflection layer; The antireflective layer comprises a high refractive index layer and a low refractive index layer stacked sequentially, and the third high refractive index layer is formed on the surface of the low refractive index layer; The refractive indices of the high refractive index layer and the third high refractive index layer are 2.50 to 2.72; The refractive index of the low-refractive-index layer is 1.46 to 1.80; The antireflective layer comprises a first high refractive index layer, a first low refractive index layer, a second high refractive index layer, and a second low refractive index layer, which are formed by sequentially stacking them. The thickness of the first high-refractive-index layer is 70–120 nm; The thickness of the second high-refractive-index layer is 35–75 nm; The thickness of the third high-refractive-index layer is 20–65 nm; The thickness of the first low-refractive-index layer is 60–150 nm; The thickness of the second low-refractive-index layer is 65–110 nm.

2. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The materials of the first high refractive index layer, the second high refractive index layer and the third high refractive index layer are selected from at least one of ZrOx, NbOx, and TiO2 films deposited using MF power or HiPIMS power, wherein 1 < x ≤ 3.

3. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The materials of the first low refractive index layer and the second low refractive index layer are selected from at least one of SiOx, SiBOx, SiTiOx, SiAlOx, SiZrOx, SiNxOy, SiBNxOy, SiTiNxOy, SiAlNxOy, and SiZrNxOy, wherein 1 < x ≤ 3 and 1 < y < 3.

4. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The antireflective layer comprises a fourth high refractive index layer, a fourth low refractive index layer, a fifth high refractive index layer, and a fifth low refractive index layer, which are sequentially stacked on the surface of the glass substrate. The refractive indices of the fourth high refractive index layer and the fifth high refractive index layer are 1.90 to 2.

72. The refractive indices of the fourth and fifth low-refractive-index layers are 1.46 to 1.

60.

5. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 4, characterized in that, The materials of the fourth and fifth high refractive index layers are selected from at least one of SiNx, SiAlNx, SiBNx, SiTiNx, SiZrNx, ZnAlOx, ZnOx, ZnSnOx, NbOx, ZrOx, and TiO2 films deposited using an MF power supply or HiPIMS, wherein 1 < x < 3.

6. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 5, characterized in that, The thickness of the fourth high-refractive-index layer is 5–30 nm.

7. The semi-reflective rearview mirror lens according to claim 5, characterized in that, The thickness of the fifth high-refractive-index layer is 15–45 nm.

8. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 4, characterized in that, The materials of the fourth and fifth low-refractive-index layers are selected from at least one of SiOx, SiBOx, SiTiOx, SiAlOx, and SiZrOx, where 1 < x < 3.

9. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 8, characterized in that, The thickness of the fourth low-refractive-index layer is 30–55 nm.

10. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 8, characterized in that, The thickness of the fifth low-refractive-index layer is 85–120 nm.

11. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The Lab value of the visible light reflection color of the semi-reflective and semi-transparent automotive rearview mirror lens has the following values: a = -1 ≤ a ≤ 1; b = -1 ≤ b ≤ 1; and visible light reflectance R = 60 ≤ R ≤ 85.

12. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The Lab value of the visible light transmission color of the semi-reflective and semi-transparent automotive rearview mirror lens has the following values: a ≤ 2; and the visible light transmittance T is 15 ≤ T ≤ 40.

Images