A kind of semi-reflective semi-transmissive automotive rearview mirror lens and its preparation method

Abstract

The application relates to the technical field of automobile parts, in particular to a semi-reflective and semi-transmissive automobile interior rearview mirror lens and a preparation method thereof. The semi-reflective and semi-transmissive automobile interior rearview mirror lens comprises a glass substrate, at least one antireflection layer and at least one reflection-increasing layer formed on opposite surfaces of the glass substrate respectively, and a third medium refractive layer and a third high refractive layer sequentially formed on the surface of the reflection-increasing layer; the reflection-increasing layer comprises a medium refractive layer, a high refractive layer and a low refractive layer sequentially formed; the refractive indexes of the medium refractive layer and the third medium refractive layer are 1.60-2.30; the refractive indexes of the high refractive layer and the third high refractive layer are 2.30-2.72; and the refractive index of the low refractive layer is 1.46-1.80. The semi-reflective and semi-transmissive automobile interior rearview mirror lens provided by the application can display / refiect images without ghosting and chromatic aberration.

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 seat is mainly used by the driver to observe and understand the situation at the rear of the car, 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 interior rearview mirror, and optical lenses connected to a camera mounted at the rear of the car via wires, and wireless video. For example, Chinese patent CN2782478Y discloses an interior rearview mirror for automobiles. When the electronic receiving screen is on, the electronic image area of ​​the plane mirror of the interior rearview mirror fully ensures that the driver can observe the state of the rear of the car. At the same time, the left and right plane mirror image areas separated by the centrally located electronic receiving screen also meet the functional requirements of the driver to clearly observe the state of the passengers in the car behind. Chinese patent CN1087449724A discloses a multi-functional rearview mirror that improves visibility in poor lighting conditions such as glare, darkness, and rain by using an LCD anti-glare screen. Chinese patent CN200960887Y discloses an automobile rearview mirror display that can be used as an interior rearview mirror and also as a display screen for an in-vehicle imaging system.

[0003] However, existing car rearview mirrors generally suffer from image blurring due to ghosting, as well as color distortion in reflected images (bluish) and reddish images in the display area (reddish transmitted colors), resulting in unrealistic reflected and displayed images, both of which pose safety hazards to driving. Summary of the Invention

[0004] In order to overcome the defects 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 with no ghosting and no chromatic aberration in displaying / reflecting images, and a method for preparing the semi-reflective and semi-transparent automotive rearview mirror lens.

[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 opposite surfaces of the glass substrate, and a third intermediate refractive index layer and a third high refractive index layer sequentially stacked on the surface of the anti-reflection layer.

[0006] The antireflective layer comprises a medium refractive index layer, a high refractive index layer, and a low refractive index layer stacked sequentially.

[0007] The refractive indices of the intermediate refractive index layer and the third intermediate refractive index layer are 1.60 to 2.30;

[0008] The refractive indices of the high refractive index layer and the third high refractive index layer are 2.30 to 2.72;

[0009] The refractive index of the low-refractive-index layer is 1.46 to 1.80.

[0010] Furthermore, a method for preparing the aforementioned semi-reflective and semi-transparent automotive rearview mirror lens is provided, comprising the steps of forming at least one anti-reflection layer on one side of a glass substrate, forming at least one anti-reflection layer on the other side of the glass substrate, and sequentially stacking a third medium refractive index layer and a third high refractive index layer on the surface of the anti-reflection layer.

[0011] The beneficial effects of this invention are as follows: by combining anti-reflective film systems and semi-reflective / semi-transparent film systems on automotive rearview mirrors, and using HiPIMS (high-power pulsed magnetron sputtering) power to deposit a high-refractive-index TiO2 film layer with a refractive index of 2.50 to 2.72, and by utilizing a reasonable film system design, the reflectivity of the automotive rearview mirror is improved, so that the rearview image and the image displayed on the electronic display screen are clear and without ghosting, and the colors are natural and without color distortion within a wide field of view of 0 to 120°, effectively improving the safety of vehicle driving. Attached Figure Description

[0012] 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.

[0013] Figure 2 The diagram shown is an optical path diagram of a car interior rearview mirror lens with a semi-reflective and semi-transparent film and an anti-reflective film in a specific embodiment of the present invention.

[0014] Figure 3 The image shown is a morphological photograph and a table showing the compositional analysis of the TiO2 film deposited by HiPIMS power supply and MF power supply in a specific embodiment of the invention.

[0015] Figure 4 The diagram shown is a structural schematic of a rearview mirror lens for automobiles in a specific embodiment of the present invention.

[0016] Figure 5 The diagram shown is another structural schematic of the rearview mirror lens in a specific embodiment of the present invention.

[0017] Figure 6 The figures show the magnetron sputtering process parameters for depositing high-refractive-index TiO2 (n > 2.50) films using HiPIMS power supply in various embodiments and comparative examples of the present invention.

[0018] Label Explanation:

[0019] 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;

[0020] exist Figure 4 In 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;

[0021] exist Figure 5 In the middle: 11, glass substrate; 21, first intermediate refractive index layer; 22, first high refractive index layer; 23, first low refractive index layer; 31, second intermediate refractive index layer; 32, second high refractive index layer; 33, second low refractive index layer; 41, third intermediate refractive index layer; 42, third high refractive index layer; 51, fourth high refractive index layer; 53, fourth high refractive index layer; 61, fifth high refractive index layer; 63, fifth low refractive index layer. Detailed Implementation

[0022] 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.

[0023] To address the shortcomings of existing smart rearview mirrors in the market, current technology involves depositing a semi-reflective, semi-transparent film on the back side of a glass substrate (the side facing away from the incident light), with the structure as follows: Figure 1 As 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.

[0024] 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.

[0025] Table 1

[0026]

[0027] 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.

[0028] When automotive rearview mirror lenses are practically applied, since the brightness of existing displays can be adjusted, the reflectivity of the semi-reflective film (i.e., the combination of at least one anti-reflective layer, a third intermediate refractive index layer, and a third high refractive index layer described herein) can be improved through film system design. This allows for a brighter field of view and clearer information about the area behind the vehicle within the rearview mirror. The key to achieving high reflectivity in the semi-reflective film system lies in the appropriate selection of the high refractive index layer material, as illustrated in Comparative Example 1 and Example 1 below. In Comparative Example 1, ZrO2 was used. x Using TiO2 (n=2.24) as its high refractive index layer material, its visible light reflectance is only 50.8%. However, in Example 1, by using TiO2 (n=2.64) as its high refractive index material, its visible light reflectance is increased to 71.6%. Therefore, the rearview mirror of the car made with TiO2 (n=2.64) as the high refractive index material will have a brighter and clearer rear view and interior scene.

[0029] However, existing magnetron sputtering techniques, such as those using MF power supplies, struggle to prepare high-refractive-index, high-quality films. Regarding TiO2, there are three crystal structures: brookite, rutile, and anatase. Brobite TiO2 is the most difficult to synthesize. Rutile TiO2 exhibits higher stability and, compared to anatase, higher refractive index, relative density, and dielectric constant. Anatase 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 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.

[0030] Table 2

[0031] MF HiPIMS Operating power (non-average power) <120kW 100kW~2MW Power density <![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

[0032] 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.

[0033] Table 3

[0034]

[0035] 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.

[0036] 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.

[0037] Table 4

[0038] 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; where 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

[0039] One of the problems addressed by the film system design of this invention is how to avoid color distortion in the reflection of rearview mirror lenses in the presence of a high refractive index layer. In this invention, a medium refractive index layer is introduced in front of the high refractive index layer to adjust the angle of the rearview mirror lens's reflected color, ensuring that the reflected color of the rearview mirror lens is neutral between 0° and 60°, and that the reflected image from the rearview mirror in the 0° to 60° field of view is not distorted. In an optional embodiment, the medium refractive index layer is introduced between the high refractive index layer and the glass substrate, between the high refractive index layer and the low refractive index layer, and between the third high refractive index layer and the antireflective layer within the antireflective layer. See, for example, Comparative Examples 2, 3, and Example 6 below. Comparative Example 2, while using TiO2 (n=2.70) as its high-refractive-index layer material, effectively improved the reflectivity of the rearview mirror lens to 80.1%, and the rearview mirror lens exhibited neutral color reflection at angles of 0–30°. However, when visible light was incident at angles of 45° and 60°, the Lab values ​​of the reflected visible light color were -5.3 and -6.7, respectively, indicating an overall greenish tint. This meant that the rearview mirror reflected images at angles of 45°–60° had a green filter, resulting in severe distortion of the field of view. Comparative Example 3, using ZnSnO3 (n=2.09) as its high-refractive-index layer material, achieved a rearview mirror reflectivity of only 41.2%. When visible light was incident at angles of 45° and 60°, the a values ​​in the Lab values ​​of the reflected visible light color were -9.4 and -13.1, respectively, indicating an overall greenish tint. Similar to Comparative Example 2, its rearview mirror also exhibited severe distortion of the internal rearward field of view. In Example 6, by using TiO2 (n = 2.61) as the high refractive index layer material, the reflectivity of the rearview mirror is increased to 70.9%. At the same time, by introducing a medium refractive index layer in front of the high refractive index layer, the 'a' value in the Lab value of the visible light reflection color of the rearview mirror at 45° and 60° is changed, so that the visible light reflection color of the rearview mirror lens is neutral at angles from 0° to 60°, and the field of vision is real and undistorted, thereby improving the safety of driving.

[0040] Another objective of the film system design in this invention is to avoid mutual interference between the antireflective film system (i.e., the antireflective layer) and the semi-reflective film system (i.e., a combination of at least one antireflective layer, a third intermediate refractive index layer, and a third high refractive index layer), so as to achieve a semi-reflective effect and a real-world enhancement effect on reflected images. Simultaneously, the film layer thickness of the semi-reflective film system is designed to eliminate side color changes when the two film systems are combined. See, for example, Comparative Example 4 and Example 8 below. In Comparative Example 4, although TiO2 was used as the high refractive index layer material and a medium refractive index layer was introduced in front of the high refractive index layer, the rearview mirror's visible light reflectance was only 52.7% due to the unreasonable film system design. Specifically, the thicknesses of the first high refractive index layer, the first low refractive index layer, and the third high refractive index layer all exceeded the reasonable film system range. When visible light was incident at angles of 30°, 45°, and 60°, the a and b values ​​of the Lab values ​​of the visible light reflected by the rearview mirror were (4.1, -5.5), (6.1, -8.3), and (4.4, -7.8), respectively. The overall reflected color was reddish-purple, meaning that there was a reddish-purple filter in the rear view of the rearview mirror at angles of 30° to 60°, resulting in severe distortion of the field of vision. In Example 8, through a reasonable film system design, not only can the frontal reflectivity reach 67.5%, but when visible light is incident at an angle of 0° to 60°, the a and b values ​​of the Lab value of the visible light reflection of the rearview mirror are both within the neutral range. Therefore, it can effectively ensure that the rear view of the rearview mirror is real and undistorted.

[0041] Specifically, in one embodiment, 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 opposite surfaces of the glass substrate, and a third intermediate refractive index layer and a third high refractive index layer sequentially stacked on the surface of the anti-reflective layer; wherein, the anti-reflective layer includes an intermediate refractive index layer, a high refractive index layer and a low refractive index layer sequentially stacked; the refractive index of the intermediate refractive index layer and the third intermediate refractive index layer is 1.60 to 2.30; the refractive index of the high refractive index layer and the third high refractive index layer is 2.30 to 2.72; and the refractive index of the low refractive index layer is 1.46 to 1.80.

[0042] The glass substrate is a conventional rearview mirror glass substrate, such as ultra-clear glass, and its thickness can be selected according to actual needs, such as 0.7 to 3.5 mm. For example, the thickness of the glass substrate is 0.7 mm, 2.1 mm, or 3.5 mm.

[0043] In one embodiment, the antireflective layer includes at least one high-refractive-index layer and at least one low-refractive-index layer, wherein the high-refractive-index layer has a refractive index of 1.90 to 2.72, and the low-refractive-index layer has a refractive index of 1.46 to 1.60.

[0044] In one alternative implementation, see [link to implementation details]. Figure 4 and Figure 5 As shown, a first antireflection layer and a second antireflection layer are sequentially stacked on one side of the glass substrate. The first antireflection layer includes a fourth high refractive index layer and a fourth low refractive index layer sequentially stacked, and the second antireflection layer includes a fifth high refractive index layer and a fifth low refractive index layer sequentially stacked.

[0045] In one alternative implementation, see [link to implementation details]. Figure 4 and Figure 5 As shown, a first antireflective layer, a second antireflective layer, a third intermediate refractive index layer, and a third high refractive index layer are sequentially stacked on the other side of the glass substrate; wherein, the first antireflective layer includes a first intermediate refractive index layer, a first high refractive index layer, and a first low refractive index layer sequentially stacked; the second antireflective layer includes a second intermediate refractive index layer, a second high refractive index layer, and a second low refractive index layer sequentially stacked.

[0046] In one embodiment, the materials of the fourth and fifth high-refractive-index layers 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 an MF power source or TiO2 deposited using a HiPIMS power source; wherein 1 < x < 3.

[0047] 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.

[0048] In one embodiment, the thickness of the fourth high refractive index layer is 5–30 nm, the thickness of the fourth low refractive index layer is 30–55 nm, the thickness of the fifth high refractive index layer is 15–45 nm, and the thickness of the fifth low refractive index layer is 85–120 nm.

[0049] In one embodiment, the materials of the first intermediate refractive index layer, the second intermediate refractive index layer, and the third intermediate refractive index layer are selected from SiN. xSiAlN x SiBN x SiTiN x SiZrN x ZnAlO x ZnO x ZnSnO x ZrO x SiN x O y SiBN x O y SiTiN x O y SiAlN x O y SiZrN x O y At least one of the following; wherein 1 < x ≤ 3, 1 < y < 3.

[0050] In one embodiment, 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 NbO. x At least one of the following: a TiO2 film deposited using an MF power source or a TiO2 film deposited using a HiPIMS power source; wherein 1 < x ≤ 3.

[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 x O y SiAlN x O y SiZrN x O y At least one of the following; wherein 1 < x ≤ 3, 1 < y < 3.

[0052] In one embodiment, the thickness of the first intermediate refractive index layer 21 is 5–100 nm; the thickness of the first high refractive index layer 22 is 50–125 nm; the thickness of the first low refractive index layer 23 is 60–155 nm; the thickness of the second intermediate refractive index layer 31 is 5–100 nm; the thickness of the second high refractive index layer 32 is 20–75 nm; the thickness of the second low refractive index layer 33 is 65–110 nm; the thickness of the third intermediate refractive index layer 41 is 5–100 nm; and the thickness of the third high refractive index layer 42 is 15–65 nm.

[0053] It should be noted that, for ease of writing, the term "TiO2 film" is used throughout this article to refer to the film formed by MF or HiPIMS power sources. However, for TiO2 films formed using HiPIMS power sources, the material should be understood as TiO2. x , where 1.8≤X≤2.

[0054] In one embodiment, the Lab value of the color reflected by the semi-reflective rearview mirror lens for visible light incident at an 8° angle satisfies the following: a value satisfies -1≤a≤1; b value satisfies -1≤b≤1; and visible light reflectance R satisfies 60≤R≤80.

[0055] In one embodiment, the Lab value of the color reflected by the semi-reflective rearview mirror lens for visible light incident at a 30° angle satisfies the following: a value -1 ≤ a ≤ 1; b value -3 ≤ b ≤ 0.

[0056] In one embodiment, the Lab value of the color reflected by the semi-reflective rearview mirror lens at a 45° angle satisfies the following: a value -3 ≤ a ≤ 0; b value -5 ≤ b ≤ 0.

[0057] In one embodiment, the Lab value of the color reflected by the semi-reflective rearview mirror lens for visible light incident at a 60° angle satisfies: a value -4.5 ≤ a ≤ 0; b value -4.5 ≤ b ≤ 0.

[0058] In one embodiment, the Lab value of the transmissive color of the semi-reflective rearview mirror lens for visible light incident at an 8° angle satisfies: -1≤a≤1; and the visible light transmittance T satisfies: 20≤T≤40.

[0059] A further method for preparing the aforementioned semi-reflective and semi-transparent automotive rearview mirror lens is provided, comprising the steps of forming at least one anti-reflection layer on one side of a glass substrate, forming at least one anti-reflection layer on the other side of the glass substrate, and sequentially stacking a third medium refractive index layer and a third high refractive index layer on the surface of the anti-reflection layer.

[0060] In an optional embodiment, the preparation method further includes heating and annealing the coated substrate. The annealing can employ any existing high-temperature glass annealing process, such as tempering or semi-tempering. Unless otherwise specified, the embodiments and comparative examples of this invention use semi-tempering technology, with the following specific parameters (based on the heating air temperature): Heating process: preheating temperature 570℃, preheating time 240s; heating temperature 690℃, heating time 240s; Annealing process: annealing temperature 300℃, annealing time 240s.

[0061] Preparation example (taking Example 1 as an example, see...) Figure 5 )

[0062] A method for preparing a semi-reflective, semi-transparent automotive rearview mirror lens includes the following steps:

[0063] 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.

[0064] S2, Magnetron sputtering of the fourth high-refractive-index layer 51: Si3N4

[0065] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0066] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:N2 = 600:540.

[0067] Sputtering pressure: 3.3E-3 mbar; Coating thickness: 16.5 nm;

[0068] S3, Magnetron sputtering of the fourth low emissivity layer 53: SiO2

[0069] Number of targets: 2 dual rotating cathodes; Power supply for targets: MF (medium frequency power supply);

[0070] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0071] Sputtering pressure: 3.5E-3 mbar; Coating thickness: 44.7 nm;

[0072] S4, Magnetron sputtering of the fifth high-refractive-index layer 61: Si3N4

[0073] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0074] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:N2 = 600:540.

[0075] Sputtering pressure: 3.3E-3 mbar; Coating thickness: 27.4 nm;

[0076] S5, Magnetron sputtering of the fifth low-refractive-index layer 63: SiO2

[0077] Number of targets: 4 dual rotating cathodes; Target power supply: MF (medium frequency power supply);

[0078] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0079] Sputtering pressure: 3.4E-3 mbar; Coating thickness: 106.7 nm;

[0080] 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.

[0081] 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.

[0082] S8, Magnetron sputtering first refractive index layer 21: SiO x N y

[0083] Number of targets: 2 dual rotating cathodes; Power supply for targets: MF (medium frequency power supply);

[0084] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:N2:O2 = 700:100:300.

[0085] Sputtering pressure: 3.6E-3 mbar; Coating thickness: 30.4 nm;

[0086] S9, Magnetron sputtering of the first high refractive index layer 22: TiO2

[0087] Number of targets: 4 dual rotating cathodes; Power supply for targets: HiPIMS (High Power Pulsed Magnetron Sputtering Power Supply);

[0088] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:10;

[0089] Peak pulse power: 891.5kW; Pulse width: 23μs;

[0090] Pulse current: 858~899A; Pulse voltage: 935~978V;

[0091] Sputtering pressure: 2.34E-3 mbar; Coating thickness: 90.3 nm;

[0092] S10, Magnetron sputtering first low emissivity layer 23: SiO2

[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: 87.5 μm;

[0096] S11, magnetron sputtering of the second refractive index layer 31: SiO x N y

[0097] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0098] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:N2:O2 = 700:100:300.

[0099] Sputtering pressure: 3.6E-3 mbar; Coating thickness: 17.5 nm;

[0100] S12, magnetron sputtered second high refractive index layer 32: TiO2

[0101] Number of targets: 3 dual rotating cathodes; Power supply for targets: HiPIMS (High Power Pulsed Magnetron Sputtering Power Supply);

[0102] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:10;

[0103] Peak pulse power: 894.3kW; Pulse width: 23μs;

[0104] Pulse current: 861~904A; Pulse voltage: 931~975V;

[0105] Sputtering pressure: 2.34E-3 mbar; Coating thickness: 49 nm;

[0106] S13, Magnetron sputtering of the second low-refractive-index layer 33: SiO2

[0107] Number of targets: 4 dual rotating cathodes; Target power supply: MF (medium frequency power supply);

[0108] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:O2 = 700:350.

[0109] Sputtering pressure: 3.4E-3 mbar; Coating thickness: 89.2 nm;

[0110] S14, magnetron sputtering of the third refractive index layer 41: SiO x N y

[0111] Number of targets: 1 dual rotating cathode; Power supply for targets: MF (medium frequency power supply);

[0112] The target material was SiAl (Si:Al = 92:8wt%); the process gas was Ar:N2:O2 = 700:100:300.

[0113] Sputtering pressure: 3.6E-3 mbar; Coating thickness: 15.5 nm;

[0114] S15, Magnetron sputtering of the third high refractive index layer 42: TiO2

[0115] Number of targets: 2 dual rotating cathodes; Power supply for targets: HiPIMS (High Power Pulsed Magnetron Sputtering Power Supply);

[0116] The target material is configured as ceramic TiO2. x (x = 1.8); Process gas: Ar:O2 = 1000:10;

[0117] Peak pulse power: 889.4kW; Pulse width: 23μs;

[0118] Pulse current: 865~909A; Pulse voltage: 928~969V;

[0119] Sputtering pressure: 2.34E-3 mbar; Coating thickness: 25.4 nm;

[0120] S16. 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.

[0121] S17. 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.

[0122] S18. The cleaned coated sheet is heated and annealed in a tempering furnace.

[0123] S19. The lens is tested for dimensional stability and coating effect (excluding lenses with surface defects such as scratches, pits, distortion, and edge breakage). After final inspection, a car interior rearview mirror lens that can be produced is obtained.

[0124] Examples 1 to 10 and Comparative Examples 1 to 4

[0125] According to Tables 5, 7 to 9, 11, 13 and below Figure 6 (Includes film material and corresponding thickness and refractive index data, as well as preparation parameters for high refractive index layers; film number can be found in [reference needed]) Figure 5 In conjunction with the aforementioned preparation examples, automotive rearview mirror lenses were prepared, and the results are shown in Tables 6, 10, and 12, respectively.

[0126] Table 5 contains the thickness data corresponding to the film material; Table 7 contains the refractive index data corresponding to the film material; Table 8 contains the refractive index data corresponding to the film material; Table 9 contains the thickness data corresponding to the film material; Table 11 contains the thickness data corresponding to the film material; and Table 13 contains the refractive index data corresponding to the film material.

[0127] It should be noted that the TiO2 films with refractive indices n = 2.70, n = 2.64, and n = 2.61 in Tables 7, 8, 11, and 13 were all obtained by HiPIMS magnetron sputtering, while the TiO2 (n = 2.50) films in the antireflection layers of the other examples and comparative examples were obtained by MF magnetron sputtering. For specific magnetron sputtering process parameters for depositing high refractive index TiO2 (n > 2.50) films using HiPIMS, please refer to [link to relevant documentation]. Figure 6 As shown.

[0128] In the following text, optical data were measured using an Agilent Cary 7000 angle colorimeter, and the color characterization system used was the CIELab color system.

[0129] Unless otherwise specified, ultra-white glass is used as the glass substrate in the embodiments and comparative examples.

[0130] Unless otherwise specified, the unit of thickness data for each layer in the embodiments and comparative examples is nm.

[0131] Table 5

[0132]

[0133]

[0134] Table 6

[0135]

[0136]

[0137] Table 7

[0138]

[0139] As shown in Tables 5 to 7 above, although Comparative Example 1 used an anti-reflective coating to eliminate ghosting in the rear-view image and in-vehicle electronic image, the use of ZrO2... x (n=2.24) As its high refractive index layer material, its visible light reflectance is only 50.8%, which is not bright enough for the rear view and the in-vehicle scene image.

[0140] Examples 1 to 5 all use anti-reflective coatings to eliminate ghosting in the rear view image and in-vehicle electronic image, while using TiO2 (n=2.64), TiO2 (n=2.70), TiO2 (n=2.70), TiO2 (n=2.70) and TiO2 (n=2.70) as their high refractive index layer materials, respectively. That is, by increasing the refractive index of the high refractive index material, the reflectivity is increased to 71.6%, 74.6%, 76%, 67.9% and 61.6%, respectively. This makes the rear view image and the in-vehicle scene brighter and clearer.

[0141] Table 8

[0142]

[0143] Table 9

[0144]

[0145]

[0146] Table 10

[0147]

[0148] As can be seen from the data in Tables 8 to 10 above, although Comparative Example 2 used TiO2 (n = 2.70) as its high refractive index layer material, which made the rearview mirror reflectivity reach 80.1% and the rearview mirror lens reflect neutral color at angles of 0 to 30°, when visible light was incident at angles of 45° and 60°, the a value of the Lab value of the visible light reflected by the rearview mirror was -5.3 and -6.7, respectively. The overall reflected color was greenish, that is, the rearview mirror reflected the rear view image at angles of 45° to 60° with a green filter, resulting in visual distortion.

[0149] Comparative Example 3 uses ZnSnO3 (n=2.09) as its high refractive index layer material. Its rearview mirror reflectivity only reached 41.2%. When visible light is incident at angles of 45° and 60°, the a value of the Lab value of the color reflected by the rearview mirror is -9.4 and -13.1, respectively. The overall reflected color is greenish, that is, the rearview mirror reflects the rear view image at angles of 45° to 60° with a green filter, resulting in visual distortion.

[0150] Examples 6 and 7 use TiO2 (n = 2.61) and TiO2 (n = 2.50) as their high refractive index layer materials, respectively, so that the reflectivity of the rearview mirrors reaches 70.9 and 63.5, respectively. At the same time, by adding a medium refractive index layer in front of the high refractive index layer, the 'a' value in the Lab value of the visible light reflected color of the rearview mirror at 45° to 60° is changed, so that the rearview mirror lens reflects neutral colors at angles from 0° to 60°, and the rear view of the rearview mirror is true and without color loss, thereby improving the safety of driving.

[0151] Table 11

[0152]

[0153] Table 12

[0154]

[0155]

[0156] Table 13

[0157]

[0158]

[0159] As can be seen from the data in Tables 11 to 13 above, although Comparative Example 4 used TiO2 (n = 2.50) as its high refractive index layer material and added a medium refractive index layer in front of the high refractive index layer, due to the unreasonable film system design, the thickness of the first high refractive index layer 22, the first low refractive index layer 23, and the third high refractive index layer 42 all exceeded the reasonable film system range, resulting in a visible light reflectance of only 52.7%. When visible light is incident at angles of 30°, 45°, and 60°, the a and b values ​​of the Lab values ​​of the visible light reflected by the rearview mirror are (4.1, -5.5), (6.1, -8.3), and (4.4, -7.8) respectively. The overall reflected color is reddish-purple, that is, the rearview mirror wears a reddish-purple filter in the rear field of view at angles of 30° to 60°, resulting in a distorted field of view.

[0160] Through reasonable film system design, Examples 8 to 10 not only achieved frontal reflectivity of 67.5%, 71%, and 60.8% respectively, but also ensured that when visible light is incident at an angle of 0° to 60°, the a and b values ​​of the Lab value of the color reflected by the rearview mirror are neutral, and the rear view of the rearview mirror is true and color-accurate.

[0161] In summary, this invention combines antireflective film systems with semi-reflective and semi-transparent film systems for use in automotive rearview mirrors. It also utilizes HiPIMS technology to deposit TiO2 films with a refractive index of 2.50–2.72 and employs a well-designed film system to achieve high reflectivity, augmented reality within a wide field of view (0–120°), and clear and natural display of the rear view and electronic images.

[0162] 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, The glass substrate includes at least one antireflection layer and at least one antireflection layer formed on opposite surfaces of the glass substrate, and a third intermediate refractive index layer and a third high refractive index layer sequentially stacked on the surface of the antireflection layer. The antireflective layer comprises a medium refractive index layer, a high refractive index layer, and a low refractive index layer stacked sequentially. The refractive indices of the intermediate refractive index layer and the third intermediate refractive index layer are 1.60~2.30; The refractive indices of the high refractive index layer and the third high refractive index layer are 2.30~2.72; The refractive index of the low-refractive-index layer is 1.46~1.80; The high refractive index layer is a high refractive index TiO2 film deposited using a HiPIMS (high-power pulsed magnetron sputtering) power supply, with a refractive index of 2.50 to 2.

72.

2. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The antireflective layer includes at least one high-refractive-index layer and at least one low-refractive-index layer, wherein the refractive index of the high-refractive-index layer in the antireflective layer is 1.90~2.72, and the refractive index of the low-refractive-index layer in the antireflective layer is 1.46~1.

60.

3. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 2, characterized in that, A first antireflection layer and a second antireflection layer are sequentially stacked on one side of the glass substrate. The first antireflection layer includes a fourth high refractive index layer and a fourth low refractive index layer sequentially stacked, and the second antireflection layer includes a fifth high refractive index layer and a fifth low refractive index layer sequentially stacked.

4. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, A first anti-reflective layer, a second anti-reflective layer, a third medium refractive index layer, and a third high refractive index layer are sequentially stacked on the other side of the glass substrate. The first antireflective layer comprises a first medium refractive index layer, a first high refractive index layer, and a first low refractive index layer, which are stacked sequentially. The second antireflective layer comprises a second intermediate refractive index layer, a second high refractive index layer, and a second low refractive index layer, which are formed by sequentially stacking layers.

5. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 3, characterized in that, The materials for the fourth and fifth high-refractive-index layers 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 TiO2 deposited using HiPIMS power supply; Where 1 < x < 3.

6. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 3, characterized in that, 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.

7. The semi-reflective rearview mirror lens according to any one of claims 3, 5, or 6, characterized in that, The thickness of the fourth high refractive index layer is 5~30nm, the thickness of the fourth low refractive index layer is 30~55nm, the thickness of the fifth high refractive index layer is 15~45nm, and the thickness of the fifth low refractive index layer is 85~120nm.

8. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 4, characterized in that, The materials of the first refractive index layer, the second refractive index layer, and the third refractive index layer are selected from SiN. x SiAlN x SiBN x SiTiN x SiZrN x ZnAlO x ZnO x ZnSnO x ZrO x SiN x O y SiBN x O y SiTiN x O y SiAlN x O y SiZrN x O y At least one of them; Where 1 < x ≤ 3, 1 < y < 3.

9. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 4, 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 NbO. x At least one of the following: TiO2 film deposited using MF power supply or TiO2 film deposited using HiPIMS power supply; Where 1 < x ≤ 3.

10. The semi-reflective rearview mirror lens according to claim 4, characterized in that, 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 x O y SiAlN x O y SiZrN x O y At least one of them; Where 1 < x ≤ 3, 1 < y < 3.

11. The semi-reflective, semi-transparent automotive rearview mirror lens according to any one of claims 4, 8 to 10, characterized in that, The thickness of the first intermediate refractive index layer 21 is 5~100nm; the thickness of the first high refractive index layer 22 is 50~125nm; the thickness of the first low refractive index layer 23 is 60~155nm; the thickness of the second intermediate refractive index layer 31 is 5~100nm; the thickness of the second high refractive index layer 32 is 20~75nm; the thickness of the second low refractive index layer 33 is 65~110nm; the thickness of the third intermediate refractive index layer 41 is 5~100nm; and the thickness of the third high refractive index layer 42 is 15~65nm.

12. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The Lab value of the color reflected by the semi-reflective and semi-transparent automotive rearview mirror lens at an 8° angle satisfies the following: a value satisfies -1≤a≤1; b value satisfies -1≤b≤1; and visible light reflectance R satisfies 60≤R≤80.

13. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The Lab value of the color reflected by the semi-reflective and semi-transparent automotive rearview mirror lens at an incident angle of 30° satisfies the following: a value satisfies -1≤a≤1; b value satisfies -3≤b≤0.

14. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The Lab value of the color reflected by the semi-reflective and semi-transparent automotive rearview mirror lens at a 45° angle satisfies the following: a value satisfies -3≤a≤0; b value satisfies -5≤b≤0.

15. The semi-reflective rearview mirror lens according to claim 1, characterized in that, The Lab value of the color reflected by the semi-reflective and semi-transparent automotive rearview mirror lens when incident at a 60° angle satisfies the following: a value -4.5 ≤ a ≤ 0; b value -4.5 ≤ b ≤ 0.

16. The semi-reflective, semi-transparent automotive rearview mirror lens according to claim 1, characterized in that, The Lab value of the transmissive color of the semi-reflective and semi-transparent automotive rearview mirror lens for visible light incident at an 8° angle satisfies: -1≤a≤1; the visible light transmittance T satisfies: 20≤T≤40.

17. A method for preparing a semi-reflective, semi-transparent automotive rearview mirror lens as described in any one of claims 1 to 16, characterized in that, The method includes the steps of forming at least one antireflection layer on one side of a glass substrate, forming at least one antireflection layer on the other side of the glass substrate, and sequentially stacking a third intermediate refractive index layer and a third high refractive index layer on the surface of the antireflection layer.

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