CN116699736A - Semi-reflective semi-transparent automobile inner rearview mirror and preparation method thereof - Google Patents
Semi-reflective semi-transparent automobile inner rearview mirror and preparation method thereof Download PDFInfo
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- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- 239000011521 glass Substances 0.000 claims abstract description 33
- 239000000758 substrate Substances 0.000 claims abstract description 23
- 230000001965 increasing effect Effects 0.000 claims abstract description 18
- 238000001755 magnetron sputter deposition Methods 0.000 claims description 24
- 239000000463 material Substances 0.000 claims description 20
- 238000004544 sputter deposition Methods 0.000 claims description 12
- 230000005540 biological transmission Effects 0.000 claims description 5
- 230000002708 enhancing effect Effects 0.000 claims description 5
- 229910003697 SiBN Inorganic materials 0.000 claims description 4
- 238000002834 transmittance Methods 0.000 claims description 3
- 229910007717 ZnSnO Inorganic materials 0.000 claims description 2
- 238000001579 optical reflectometry Methods 0.000 abstract description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 27
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 21
- 238000000034 method Methods 0.000 description 18
- 229910010413 TiO 2 Inorganic materials 0.000 description 17
- 239000011248 coating agent Substances 0.000 description 14
- 238000000576 coating method Methods 0.000 description 14
- 238000010438 heat treatment Methods 0.000 description 13
- 238000000137 annealing Methods 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 10
- 238000002310 reflectometry Methods 0.000 description 9
- 230000003287 optical effect Effects 0.000 description 8
- 238000013461 design Methods 0.000 description 7
- 239000000919 ceramic Substances 0.000 description 5
- 239000004408 titanium dioxide Substances 0.000 description 5
- 238000005520 cutting process Methods 0.000 description 4
- 239000007888 film coating Substances 0.000 description 4
- 238000009501 film coating Methods 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 238000005507 spraying Methods 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 229910004298 SiO 2 Inorganic materials 0.000 description 3
- 230000003667 anti-reflective effect Effects 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 238000007747 plating Methods 0.000 description 3
- 230000000007 visual effect Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 239000003086 colorant Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000013077 target material Substances 0.000 description 2
- 238000005496 tempering Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910003087 TiOx Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000003190 augmentative effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000000541 cathodic arc deposition Methods 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
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- 238000002474 experimental method Methods 0.000 description 1
- 239000005357 flat glass Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- HLLICFJUWSZHRJ-UHFFFAOYSA-N tioxidazole Chemical compound CCCOC1=CC=C2N=C(NC(=O)OC)SC2=C1 HLLICFJUWSZHRJ-UHFFFAOYSA-N 0.000 description 1
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Classifications
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
- G02B1/11—Anti-reflection coatings
- G02B1/113—Anti-reflection coatings using inorganic layer materials only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
- B60R1/00—Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
- B60R1/02—Rear-view mirror arrangements
- B60R1/08—Rear-view mirror arrangements involving special optical features, e.g. avoiding blind spots, e.g. convex mirrors; Side-by-side associations of rear-view and other mirrors
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/34—Sputtering
- C23C14/35—Sputtering by application of a magnetic field, e.g. magnetron sputtering
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/08—Mirrors
- G02B5/0816—Multilayer mirrors, i.e. having two or more reflecting layers
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- Chemical & Material Sciences (AREA)
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- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Multimedia (AREA)
- Optical Elements Other Than Lenses (AREA)
Abstract
The invention relates to the technical field of automobile parts, in particular to a semi-reflective semi-transparent automobile inner rearview mirror and a preparation method thereof. The semi-reflective semi-transparent automobile inner rearview mirror comprises a glass substrate, at least one antireflection layer and at least one antireflection layer which are respectively formed on two sides of the glass substrate, and a third high refractive index layer formed on the surface of the antireflection layer; the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer; the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72; the refractive index of the low refractive index layer is 1.46-1.80. The semi-reflective semi-transparent automobile inner rearview mirror lens provided by the invention can effectively improve the visible light reflectivity of the rearview mirror and simultaneously avoid the color cast of images.
Description
Technical Field
The invention relates to the technical field of automobile parts, in particular to a semi-reflective semi-transparent automobile inner rearview mirror and a preparation method thereof.
Background
The automobile indoor rearview mirror in the cab is mainly used for a driver to observe and know the condition of the tail of the automobile and observe the condition of passengers behind the driver in the automobile. The structure and the structure of the electronic display screen are repeatedly improved, and the electronic display screen is embedded in an indoor rearview mirror from a simple plane mirror, and the electronic display screen is combined with an optical lens connected with a camera arranged at the tail part of an automobile by using a lead.
In general, a half mirror is used as an optical lens of a rearview mirror, that is, a half mirror has a reflectance of 50% and a transmittance of 50% with respect to a visible light, but such a half mirror has a problem of insufficient reflectance. To increase the reflectivity of the indoor rearview mirror, chinese patent CN209619202U is prepared by plating Nb 2 O 5 /SiO 2 /Nb 2 O 5 /SiO 2 /Nb 2 O 5 /SiO 2 To enhance the reflectivity of the mirror. Although such an antireflection layer structure can enhance the reflectivity of the rear view mirror, there is a problem of image blurring due to image ghosting. Meanwhile, the problems of color distortion (bluish), red transmission (red display area image) and the like cannot be considered, and potential safety driving hazards exist.
Disclosure of Invention
In order to overcome the defects in the prior art, the technical problems to be solved by the invention are as follows: the semi-reflective semi-transparent automobile inner rearview mirror lens capable of effectively avoiding visual field distortion and the preparation method thereof are provided.
In order to solve the technical problems, the invention provides a semi-reflective semi-transparent automobile inner rearview mirror lens, which comprises a glass substrate, at least one antireflection layer and at least one antireflection layer which are respectively formed on two sides of the glass substrate, and a third high refractive index layer formed on the surface of the antireflection layer;
the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer;
the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72;
the refractive index of the low refractive index layer is 1.46-1.80.
The preparation method of the semi-reflective semi-transparent automobile inner rearview mirror lens comprises the steps of forming an anti-reflection layer and an anti-reflection layer on two sides of a glass substrate through magnetron sputtering respectively;
and sputtering a third high refractive index layer on the surface of the reflection increasing layer in a magnetron manner;
the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer;
the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72;
the refractive index of the low refractive index layer is 1.46-1.80.
The invention has the beneficial effects that: the invention reasonably designs the film layer structure of the semi-reflective and semi-transparent film on the inner surface of the automobile inner rearview mirror lens to improve the visible light reflectivity of the automobile rearview mirror, and simultaneously realizes clear image without double image and natural color without color cast of the displayed image by combining the anti-reflective film deposited on the outer surface of the rearview mirror lens, thereby effectively improving the driving safety of the automobile.
Drawings
FIG. 1 is a schematic view of a conventional mirror plate for an automobile interior mirror with a semi-reflective and semi-permeable membrane according to the present invention;
FIG. 2 is a schematic view showing an optical path of an antireflection film formed on the surface of a conventional mirror plate for an automobile interior rear view mirror having a semi-reflective and semi-transmissive film according to the present invention;
FIG. 3 shows the deposition of TiO from HiPIMS power and MF power in an embodiment of the present invention 2 The morphology photo of the film and the composition of relevant components form an analysis table;
FIG. 4 is a schematic view showing a structure of a half-reflecting and half-transmitting inner mirror lens of an automobile according to the present invention in a specific embodiment;
fig. 5 is a schematic view showing another structure of a semi-reflective and semi-transmissive mirror for an automobile according to the present invention in an embodiment.
Description of the reference numerals:
in fig. 1 and 2: 11. a light source; 22 31, 42, refracting light; 21 32, reflecting light; 4. a semi-reflective semi-permeable membrane; 5. a glass substrate; 6. an antireflection film;
in fig. 4: 1. a glass substrate; 2. a first reflection enhancing layer; 3. a second reflection enhancing layer; 4. a third high refractive index layer; 5. a first anti-reflection layer; 6. a second anti-reflection layer;
in fig. 5: 11. a glass substrate; 21. a first high refractive index layer; 22. a first low refractive index layer; 31. a second high refractive index layer; 32. a second low refractive index layer; 41. a third high refractive index layer; 51. a fourth high refractive index layer; 52. a fourth high refractive index layer; 61. a fifth high refractive index layer; 62. and a fifth low refractive index layer.
Detailed Description
In order to describe the technical contents, the achieved objects and effects of the present invention in detail, the following description will be made with reference to the embodiments in conjunction with the accompanying drawings.
A semi-reflective semi-transparent automobile inner rearview mirror comprises a glass substrate, at least one antireflection layer and at least one antireflection layer which are respectively formed on two sides of the glass substrate, and a third high refractive index layer formed on the surface of the antireflection layer; the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer; the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72; the refractive index of the low refractive index layer is 1.46-1.80.
The specific combination of the high refractive index layer and the low refractive index layer is utilized to adjust the reflectivity of the reflection increasing layer, and the reflection reducing layer is combined to improve the problems of image double image, color cast and the like. Specifically, in order to solve the defects of the existing intelligent rearview mirrors in the market, a semi-reflective and semi-transparent film is plated on the back surface (the side surface facing away from the incident light) of a glass substrate, and the structure of the semi-reflective and semi-transparent film is shown in fig. 1. The semi-reflective and semi-permeable membrane 4 is located inside the mirror, i.e. between the display screen and the glass substrate 5. When a human eye views the rear view through the rearview mirror, a certain included angle (transverse/longitudinal included angle) is formed between the human eye and the rearview mirror, and the rear light source 11 (100%) is incident to the glass interface from the air, so that reflected light rays 21 and refracted light rays 22 are generated, and only about 4% of the reflected light rays 21 enter the human eye. Since the film layer (semi-reflective and semi-permeable film 4) is excessively thin in overall thickness, reflection and refraction of the refracted light rays 22 in the semi-reflective and semi-permeable film 4 can be temporarily ignored. At this time, the refracted ray 22 also generates reflected ray 32 and refracted ray 31 from the glass/film, air interface, and the reflected ray 32 is about 46% because the film is designed to have semi-reflective and semi-transmissive properties, and thus the refracted ray 31 is about 50%. The reflected light 32 reflects off the glass substrate 5, again creating reflected light (shown in phantom, but not considered due to the small amount) and refracted light 42 (about 42%) at the glass/air interface, where the refracted light 42 enters the human eye. Therefore, since the sub-image (4%) formed by the reflected light ray 21 and the main image (about 46%) formed by the refracted light ray 42 are simultaneously entered into the eyes, both the brightness is relatively large, thereby causing image blurring in the human eye. Meanwhile, the brightness ratio of the two increases with the increase of the observation angle. Similarly, the image displayed on the rear view mirror rear display screen also becomes blurred in the human eye.
On the basis of the prior art, the structure of the antireflection film is shown in fig. 2. As can be seen from the figure, the antireflection film 6 can significantly reduce the luminance of the sub-image and enhance the luminance of the main image, and thus the luminance ratio of the sub-image (0.5%) formed by the reflected light ray 21 and the main image (about 49.5%) formed by the refracted light ray 42 is reduced, thereby achieving the effect of augmented reality and avoiding the occurrence of ghost images. The specific data are shown in table 1.
TABLE 1
Reflectance of secondary image (%) | 0° | 15° | 30° | 45° | 60° |
3.5mm super white glass | 4.4 | 4.4 | 4.5 | 5.1 | 8.1 |
3.5mm ultra-white glass + antireflection film | 0.3 | 0.3 | 0.4 | 1.3 | 5 |
As can be seen from table 1, the anti-reflective film can effectively reduce the reflectivity of the secondary image while the brightness of the primary image is improved, so that the brightness ratio of the secondary image to the primary image can be reduced by plating the anti-reflective film on the outer surface of the glass substrate, thereby avoiding the occurrence of the ghost phenomenon.
Because the brightness of the existing display can be adjusted, the reflectivity of the semi-reflective and semi-transparent film (namely the combination of the enhanced reflection layer and the third high refractive index layer) is improved through the design of the film layer, so that a brighter visual field can be obtained in the inner rearview mirror, and clearer automobile rear information can be obtained. For example, see comparison of comparative example 1 and example 6 below, comparative example 1 uses Si 3 N 4 (n=2.13) as the high refractive index layer material, the visible light reflectance thereof was only 46.4%, whereas example 6 was carried out by using TiO 2 (n=2.70) as a high refractive index material, that is, the reflectance is increased to 80.1% by the high refractive index material, so that the influence of the field of view in the rear of the automobile and the influence of the inside of the automobile can be effectively improved in the sharpness in the inside rear view mirror.
High quality, high refractive index TiO 2 The film is difficult to prepare under the magnetron sputtering condition using an MF power supply. Specifically, tiO 2 The material has three crystal structures including brookite type TiO 2 Rutile TiO 2 Anatase TiO 2 . Among them, brookite type synthesis is more difficult. The rutile form has a higher stability, and has a higher refractive index, relative density, and dielectric constant than anatase. Anatase is a metastable phase, and as the heating temperature increases, tiO 2 The phases of the film undergo a microstructural transformation of the amorphous-anatase phase-anatase and rutile mixed phase-rutile phase. According to the description of the prior related literature, tiO 2 The heating temperature for completely converting the film into the rutile state needs to reach more than 1000 ℃. However, tiO is deposited from conventional MF sources 2 After the film layer is heated and annealed (600-790 ℃), the film layer is difficult to be completely converted into a rutile structure due to the insufficient heating temperature, and the refractive index n of the annealed film layer is generally limited to be less than or equal to 2.50, so that the film layer with the refractive index larger than 2.50 is difficult to prepare. Meanwhile, conventional MF power supply magnetron sputtering deposited TiO 2 The film layer has less ions and lower ionization rate. Although vacuum cathodic arc deposition can produce very high particle ionization rate, it can produce large particles of metal/metal compounds causing excessive coating impurities, and the cathode is overheated requiring increased cooling requirements, thus being difficult to be suitable for the automotive glass coating industry. The HiPIMS power supply has higher pulse peak power and lower pulse duty ratio, and has no extra requirement on cathode cooling when ensuring high ionization rate, so the HiPIMS power supply is suitable for the use of the automobile glass coating industry. Relevant comparative parameters of HiPIMS (high power pulsed magnetron sputtering) power supply and MF power supply are shown in table 2.
TABLE 2
MF | HiPIMS | |
Working power (non-average power) | <120kW | 100kW~2MW |
Peak power | 10W/cm 2 Stage | 1~3KW/cm 2 Stage |
Current density | 10mA/cm 2 Stage | 1~5A/cm 2 Stage |
Duty cycle | 100% | 1%~15% |
Operating voltage | 0~800V | 0~2000V |
Operating current | 0~200A | 0~1000A |
Ionization rate | 30%~40% | Up to > 80% |
Film layer attachment force | Weak and weak | Strong strength |
Meanwhile, it has been demonstrated in preliminary experiments that TiO is deposited using HiPIMS power supply 2 The film layer had a rutile structure and the results are shown in table 3 and fig. 3.
TABLE 3 Table 3
Therefore, the TiO with the refractive index n of 2.50-2.72 after the heating annealing can be obtained by adjusting the power supply parameters of the HiPIMS 2 And (3) a film layer. And benefit from TiO x High ionization rate of the film layer, and TiO during the heating annealing process of the antireflection film system x The film layer can be more transformed towards the rutile structure.
In a process for preparing TiO having a refractive index n of 2.50 to 2.72 x In the embodiment of the single film layer, the process parameters are shown in table 4.
TABLE 4 Table 4
Sequence number | Project | Parameters (parameters) |
1 | Power supply | HiPIMS power supply |
2 | Target material | TiO x A target material, wherein x is more than or equal to 1.8 and less than or equal to 1.9 |
3 | Process gas | Ar、O 2 The method comprises the steps of carrying out a first treatment on the surface of the Wherein O is 2 The inlet amount is 0-30 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 |
Although the combination of such double layers (antireflection layer and semi-reflective and semi-transparent film) canThe generation of double images can be effectively avoided, but the film system interference is easy to be caused due to the different color systems of the film layers, so that the display color is changed. Therefore, in the invention, the antireflection film system and the semi-reflection and semi-transmission film system are not interfered with each other by reasonably designing the film layers of the semi-reflection and semi-transmission film system, so that the rearview mirror lens can not only play the role of semi-reflection and semi-transmission, but also make the image clear and not ghost through the antireflection film, and meanwhile, the color change of the image generated by different color systems of the two double film layers is eliminated by reasonably designing the film layers of the semi-reflection and semi-transmission film system. The refractive index of the main film layer is adjusted and the thickness of the film layer is selected for reasonably designing the semi-reflective and semi-permeable film system. The thickness of the film layer is an important feature for determining the color cast of the visual field. With specific reference to comparative example 2 and example 3 below, it can be seen from the data that comparative example 2 uses TiO 2 (n=2.50) as a high refractive index layer material, the reflectance of the inner mirror can reach 65.2%, but due to unreasonable film system design, the film thicknesses of the first high refractive index layer 21, the first low refractive index layer 22 and the second low refractive index layer 32 are all out of a reasonable film system range, so that when visible light is incident at an angle of 30 degrees, the value a in the Lab value of the reflection color of the mirror for visible light is 3.4, the value b is-5.4, the overall reflection color is reddish purple, namely, a reddish purple filter exists in the rear view of the mirror reflected at an angle of 30 degrees, and the view is severely distorted. In example 3, the thickness of each layer of the film system is controlled within a reasonable film system range by reasonably designing the film system, and when visible light is incident at an angle of 30 degrees, the value a and the value b in the Lab value of the visible light reflection color of the rearview mirror are close to neutrality, so that the rear view image in the rearview mirror is truly undistorted.
In one embodiment, as shown in fig. 4, the half-reflecting and half-transmitting inner rearview mirror lens comprises two layers of reflection increasing layers, namely a first reflection increasing layer 2 and a second reflection increasing layer 3, which are arranged layer by layer, wherein the two reflection increasing layers are positioned between the glass substrate 1 and a third high refractive index layer 4, and the reflection increasing layers consist of at least one high refractive index layer and at least one low refractive index layer.
In another embodiment, as shown in fig. 5, the reflection enhancing 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 sequentially stacked and formed on the surface of the glass substrate 1.
Wherein 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 TiO deposited using MF power supply or HiPIMS power supply 2 At least one of the film layers, wherein x is more than 1 and less than or equal to 3. That is, in this embodiment, tiO having a refractive index n of greater than 2.50, preferably having a refractive index n of 2.50 to 2.72, can be deposited by magnetron sputtering using HiPIMS power supply 2 And (3) a film layer.
It should be noted that, for convenience of writing, the film layer formed by MF or HiPIMS power source is referred to herein as a TiO2 film layer, but the material of the TiO2 film layer formed by HiPIMS power source should be understood as TiOx, where 1.8.ltoreq.x.ltoreq.2.
In a preferred embodiment, the first high refractive index layer has a thickness of 70 to 120nm.
In a preferred embodiment, the second high refractive index layer has a thickness of 35 to 75nm.
In a preferred embodiment, the thickness of the third high refractive index layer is 20 to 65nm.
In one embodiment, the material of the first low refractive index layer and the second low refractive index layer is selected from SiO 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 Wherein x is more than 1 and less than or equal to 3, and y is more than 1 and less than 3.
In a preferred embodiment, the first low refractive index layer has a thickness of 60 to 150nm.
In a preferred embodiment, the second low refractive index layer has a thickness of 65 to 110nm.
In one embodiment, the anti-reflection layer includes 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 laminated on the surface of the glass substrate; wherein the refractive index of the fourth high refractive index layer and the fifth high refractive index layer is 1.90-2.72; the fourth low refractive index layer and the fifth low refractive index layer have refractive indices of 1.46 to 1.60.
Wherein the material of the fourth high refractive index layer and the fifth high refractive index layer is selected from SiN x 、SiAlN x 、SiBN x 、SiTiN x 、SiZrN x 、ZnAlO x 、ZnO x 、ZnSnO x 、NbO x 、ZrO x TiO deposited using MF power supply or HiPIMS 2 At least one of the film layers, wherein 1 < x < 3.
In a preferred embodiment, the fourth high refractive index layer has a thickness of 5 to 30nm.
In a preferred embodiment, the fifth high refractive index layer has a thickness of 15 to 45nm.
In one embodiment, the material of the fourth low refractive index layer and the fifth low refractive index layer is selected from SiO x 、SiBO x 、SiTiO x 、SiAlO x 、SiZrO x Wherein 1 < x < 3.
In a preferred embodiment, the fourth low refractive index layer has a thickness of 30 to 55nm.
In a preferred embodiment, the fifth low refractive index layer has a thickness of 85 to 120nm.
Preferably, the value a in the Lab value of the visible light reflection color of the semi-reflective semi-transmissive automobile inner rearview mirror lens is: -1.ltoreq.a.ltoreq.1; the value b is: b is more than or equal to-1 and less than or equal to-1; the visible light reflectance R is: r is more than or equal to 60 and less than or equal to 85.
Preferably, the value a in the Lab value of the visible light transmission color of the semi-reflective semi-transmissive automobile inner rearview mirror lens is as follows: a is less than or equal to 2; the visible light transmittance T is: t is more than or equal to 15 and less than or equal to 40.
A preparation method of a semi-reflective semi-transparent automobile inner rearview mirror lens comprises the steps of forming an anti-reflection layer and an anti-reflection layer on two sides of a glass substrate by magnetron sputtering respectively; and sputtering a third high refractive index layer on the surface of the reflection increasing layer in a magnetron manner; the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer; the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72; the refractive index of the low refractive index layer is 1.46-1.80.
In one embodiment, the reflection enhancing 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.
Wherein 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 TiO deposited using MF power supply or HiPIMS power supply 2 At least one of the film layers, wherein x is more than 1 and less than or equal to 3.
In one embodiment, the method further comprises the step of thermally annealing the coated lens. The heating annealing can adopt any existing high-temperature annealing process, such as tempering, semi-tempering and the like. In an exemplary embodiment, semi-hardening techniques are employed, the parameters of which are: heating process (with the temperature of the heated air as a set standard): preheating temperature is 570 ℃, and preheating time is 240s; heating temperature is 690 ℃, and heating time is 240s; annealing temperature 300 ℃ and annealing time 240s.
Preparation example (taking example 3 as an example)
Referring to fig. 5, a method for preparing a semi-reflective semi-transparent inner rearview mirror of an automobile comprises the following steps:
s1, washing and drying float ultrawhite plate glass with the thickness of 3.5mm, and then entering a magnetron sputtering coating line to coat an antireflection film layer;
s2, magnetron sputtering a fourth high refractive index layer 51: tiO (titanium dioxide) 2 The parameters are as follows:
target number: 1 double-rotating cathode; and (3) a target power supply: MF (intermediate frequency power supply);
the target is configured as ceramic TiO x (x=1.8); process gas: ar: o (O) 2 =1000:30;
Sputtering gas pressure2.8E -3 mbar; the thickness of the coating is 16.1nm;
s3, magnetron sputtering a fourth low-emissivity layer 52: siO (SiO) 2 The parameters are as follows:
target number: 2 double rotary cathodes; and (3) a target power supply: MF (intermediate frequency power supply);
the target was configured as SiAl (Si: al=92:8 wt%); process gas: ar: O 2 =700:350;
Sputtering air pressure 3.5E -3 mbar; the thickness of the coating film is 40.7nm;
s4, magnetron sputtering a fifth high refractive index layer 61: tiO (titanium dioxide) 2 The parameters are as follows:
target number: 1 double-rotating cathode; and (3) a target power supply: MF (intermediate frequency power supply);
the target is configured as ceramic TiO x (x=1.8); process gas: ar: o (O) 2 =1000:30;
Sputtering air pressure 2.8E -3 mbar; the thickness of the coating is 24.1nm;
s5, magnetron sputtering a fifth low refractive index layer 62: siO (SiO) 2 The parameters are as follows:
target number: 4 double rotary cathodes; and (3) a target power supply: MF (intermediate frequency power supply);
the target was configured as SiAl (Si: al=92:8 wt%); process gas: ar: O 2 =700:350;
Sputtering air pressure 3.4E -3 mbar; the thickness of the coating film is 104nm;
s6, after film coating is completed, optical testing and quality inspection are carried out on the antireflection film layer, and the optical testing is completed and is transmitted to a powder spraying machine for powder spraying and film collecting;
s7, after being fully packed, the film is transported to a film coating line film placing position and is rotated by using a crane, and after washing and drying, the film enters a magnetron sputtering film coating line to plate a semi-reflective semi-transparent film layer;
s8, magnetron sputtering a first high refractive index layer 21: tiO (titanium dioxide) 2 The parameters are as follows:
target number: 2 double rotary cathodes; and (3) a target power supply: MF (intermediate frequency power supply);
the target is configured as ceramic TiO x (x=1.8); process gasThe body: ar: o (O) 2 =1000:30;
Sputtering air pressure 2.8E -3 mbar; the thickness of the coating film is 95.7nm;
s9, magnetron sputtering a first low-emissivity layer 22: siO (SiO) 2 The parameters are as follows:
target number: 4 double rotary cathodes; and (3) a target power supply: MF (intermediate frequency power supply);
the target was configured as SiAl (Si: al=92:8 wt%); process gas: ar: O 2 =700:350;
Sputtering air pressure 3.4E -3 mbar; the thickness of the coating is 88.4nm;
s10, magnetron sputtering the second high refractive index layer 31: tiO (titanium dioxide) 2 The parameters are as follows:
target number: 2 double rotary cathodes; and (3) a target power supply: MF (intermediate frequency power supply);
the target is configured as ceramic TiO x (x=1.8); process gas: ar: o (O) 2 =1000:30;
Sputtering air pressure 2.8E -3 mbar; the thickness of the coating is 58.4nm;
s11, magnetron sputtering the second low refractive index layer 32: siO (SiO) 2 The parameters are as follows:
target number: 4 double rotary cathodes; and (3) a target power supply: MF (intermediate frequency power supply);
the target was configured as SiAl (Si: al=92:8 wt%); process gas: ar: O 2 =700:350;
Sputtering air pressure 3.4E -3 mbar; the thickness of the coating film is 97.3nm;
s12, magnetron sputtering the third high refractive index layer 41: tiO (titanium dioxide) 2 The parameters are as follows:
target number: 1 double-rotating cathode; and (3) a target power supply: MF (intermediate frequency power supply);
the target is configured as ceramic TiO x (x=1.8); process gas: ar: o (O) 2 =1000:30;
Sputtering air pressure 2.8E -3 mbar; the thickness of the coating is 33.3nm;
s13, after film coating is completed, carrying out optical test and quality inspection on the whole film layer, and conveying the optical test to a powder spraying machine for powder spraying and film collecting, and conveying to a cutting procedure after one package is fully collected;
s14, cutting the film-plated raw sheet into rectangular small sheets by using a glass cutting machine, cutting glass into the size of a rearview mirror drawing by using a CNC (computer numerical control) processing center, edging, cleaning the film-plated raw sheet by using pure water and a hairbrush to clean dirt on the surface of the film-plated raw sheet, and drying to provide clean condition guarantee for the next glass semi-steel so as to avoid the problems of spotting, distortion and the like of a mirror surface;
s15, heating and annealing the cleaned film-coated raw sheet in a toughening furnace, wherein the specific parameters are as follows: heating process (with the temperature of the heated air as a set standard): preheating temperature is 570 ℃, and preheating time is 240s; heating temperature is 690 ℃, and heating time is 240s; annealing temperature 300 ℃ and annealing time 240s.
S16, detecting the dimensional stability and the coating effect (the lens with defects such as scratches, pits, distortion, edge burst and the like on the surface are eliminated) of the lens, and finally checking to obtain the finished automobile inner rear view mirror lens.
Examples 1 to 12 and comparative examples 1 and 2
Automobile interior mirror lenses were prepared according to the following tables 5 and 10 (including film layer materials and corresponding thickness data) in combination with the previous preparation examples, and the results are shown in tables 8 and 10, respectively.
Wherein the optical data were measured using an Agilent Cary 7000 angle colorimeter and the color characterization system using the CIELab color system.
In table 7, the fifth high refractive index layer, the fourth high refractive index layer, the first high refractive index layer, the second high refractive index layer, and the third high refractive index layer in example 3 were each TiO formed by magnetron sputtering from MF power supply 2 A film layer; in example 4, the fifth high refractive index layer and the fourth high refractive index layer were each TiO formed by magnetron sputtering from MF power supply 2 A film layer; in example 5, the fifth high refractive index layer and the fourth high refractive index layer are both TiO formed by magnetron sputtering from MF power supply 2 A film layer; in example 6, the fifth high refractive index layer and the fourth high refractive index layer were each TiO formed by magnetron sputtering from MF power supply 2 Film layer. The rest of the TiO 2 The film layers are TiO formed by magnetron sputtering of HiPIMS power supply 2 And (3) a film layer. The TiO of tables 7 and 8 is formed by magnetron sputtering from MF power supply, without specific explanation 2 The refractive index of the film layers was 2.50.
Unless otherwise indicated, all of the following substrates were ultrawhite glass.
TABLE 5
TABLE 6
TABLE 7
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TABLE 8
As is clear from comparative examples 1 to 6 and comparative example 1, examples 1 to 6 show no double image of the rear view field and the display image of the rear view mirror after the antireflection film layer is additionally coated on the outer surface of the mirror piece of the rear view mirrorThe image is clear and real, and the safety of vehicle running is improved. Comparative example 1 Using Si 3 N 4 (n=2.13) as the material of the high refractive index layer, the reflectance of the mirror lens was only 46.4%, and ZrO was used in each of examples 1 to 6 x (n=2.24)、Nb 2 O 5 (n=2.38)、TiO 2 (n=2.50)、TiO 2 (HiPIMS-n=2.61)、TiO 2 (HiPIMS-n=2.64)、TiO 2 (HiPIMS-n=2.70) as the materials of the first high refractive index layer, the second high refractive index layer and the third high refractive index layer, the reflectivity of the rearview mirror is 60.6%, 71.8%, 72.7%, 78.1%, 79.1% and 80.1%, and the reflectivity of the rearview mirror is greatly improved.
In examples 1 to 6, the values a and b of the Lab values of the visible light reflection colors are all kept within the neutral color range when the visible light is incident at 0 to 30 degrees by a reasonable film system design, and the rearview mirror does not color the vehicle tail reflection image. Meanwhile, the value a of the Lab value of the visible light transmission color is in the range of-1 < a < 2, which indicates that the transmission color is neutral, and the image displayed by the electronic display screen has no double image and no color cast.
Examples 1 to 6 use of high refractive index material ZrO by plating a visible light anti-reflection layer on an outer surface of a rear view mirror x (n=2.24)、Nb 2 O 5 (n=2.38)、TiO 2 (n=2.50)、TiO 2 (HiPIMS-n=2.61)、TiO 2 (HiPIMS-n=2.64)、TiO 2 (HiPIMS-n=2.70) is used as a high refractive index layer, and the film system design is reasonably carried out, so that the visible light reflectivity of the automobile rearview mirror is improved, the rear view image of the rearview mirror and the image displayed by the electronic display screen are clear and have no double image, the color is natural and has no color cast, and the safety of the running of the automobile is improved.
TABLE 9
Table 10
As can be seen from the above table data, comparative example 2 uses TiO 2 (n=2.50) is used as a high refractive index layer material, so that the reflectivity of the rearview mirror reaches 65.2%, but due to unreasonable film system design, 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 are all beyond the reasonable film system range, so that when visible light is incident at an angle of 30 degrees, the value a in the Lab value of the reflection color of the rearview mirror on the visible light is 3.4, the value b is-5.4, the whole reflection color is reddish purple, namely, a red-purple filter is worn on the rear view of the rearview mirror, and the view is distorted.
And by reasonable film system design, the embodiment 7-12 has the advantages that when visible light is incident at an angle of 0-30 degrees, the value a and the value b in the Lab value of the visible light reflection color of the rearview mirror are neutral, the visible light reflectivity of the automobile rearview mirror is improved, the rear view image of the rearview mirror and the image displayed by the electronic display screen are clear and have no ghost, the color is natural and has no color cast, and the safety of vehicle running is improved.
In summary, the antireflection film is deposited on the outer surface of the rearview mirror lens, and the semi-reflection and semi-transparent film layer is reasonably designed on the inner surface of the rearview mirror lens, so that the visible light reflectivity of the automobile rearview mirror is improved, the images displayed by the rear view image and the electronic display screen of the rearview mirror are clear and have no double images, the colors are natural and have no color cast, and the driving safety of the automobile is improved.
The foregoing description is only illustrative of the present invention and is not intended to limit the scope of the invention, and all equivalent changes made by the specification and drawings of the present invention, or direct or indirect application in the relevant art, are included in the scope of the present invention.
Claims (19)
1. The semi-reflective semi-transparent automobile inner rearview mirror is characterized by comprising a glass substrate, at least one antireflection layer and at least one antireflection layer which are respectively formed on two sides of the glass substrate, and a third high refractive index layer formed on the surface of the antireflection layer;
the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer;
the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72;
the refractive index of the low refractive index layer is 1.46-1.80.
2. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 1, wherein the reflection enhancing 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 sequentially laminated.
3. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 2, wherein the materials of the first, second and third high refractive index layers are selected from ZrO x 、NbO x TiO deposited using MF power supply or HiPIMS power supply 2 At least one of the film layers, wherein x is more than 1 and less than or equal to 3.
4. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 3, wherein the thickness of the first high refractive index layer is 70 to 120nm.
5. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 3, wherein the second high refractive index layer has a thickness of 35 to 75nm.
6. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 3, wherein the thickness of the third high refractive index layer is 20 to 65nm.
7. The semi-reflective semi-transparent automobile interior rear view according to claim 2A mirror plate, characterized in that the material of the first low refractive index layer and the second low refractive index layer is selected from SiO 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 Wherein x is more than 1 and less than or equal to 3, and y is more than 1 and less than 3.
8. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 7, wherein the thickness of the first low refractive index layer is 60 to 150nm.
9. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 7, wherein the thickness of the second low refractive index layer is 65-110 nm.
10. The half-reflecting half-transmitting automobile inner rear view mirror according to claim 1, wherein the antireflection 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 laminated in this order on the surface of the glass substrate;
wherein the refractive index of the fourth high refractive index layer and the fifth high refractive index layer is 1.90-2.72;
the fourth low refractive index layer and the fifth low refractive index layer have refractive indices of 1.46 to 1.60.
11. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 10, wherein the fourth and fifth high refractive index layers are made of a material selected from SiN x 、SiAlN x 、SiBN x 、SiTiN x 、SiZrN x 、ZnAlO x 、ZnO x 、ZnSnO x 、NbO x 、ZrO x TiO deposited using MF power supply or HiPIMS 2 At least one of the film layers, wherein 1 < x < 3.
12. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 11, wherein the fourth high refractive index layer has a thickness of 5 to 30nm.
13. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 11, wherein the thickness of the fifth high refractive index layer is 15 to 45nm.
14. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 10, wherein the fourth and fifth low refractive index layers are made of a material selected from the group consisting of SiO x 、SiBO x 、SiTiO x 、SiAlO x 、SiZrO x Wherein 1 < x < 3.
15. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 14, wherein the fourth low refractive index layer has a thickness of 30 to 55nm.
16. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 14, wherein the thickness of the fifth low refractive index layer is 85-120 nm.
17. The semi-reflective semi-transmissive automobile interior mirror lens according to claim 1, wherein a value of Lab value of visible light reflection color of the semi-reflective semi-transmissive automobile interior mirror lens is: -1.ltoreq.a.ltoreq.1; the value b is: b is more than or equal to-1 and less than or equal to-1; the visible light reflectance R is: r is more than or equal to 60 and less than or equal to 85.
18. The semi-reflective semi-transmissive automobile interior rear view mirror lens according to claim 1, wherein a value of Lab value of visible light transmission color of the semi-reflective semi-transmissive automobile interior rear view mirror lens is: a is less than or equal to 2; the visible light transmittance T is: t is more than or equal to 15 and less than or equal to 40.
19. The preparation method of the semi-reflective semi-transparent automobile inner rearview mirror lens is characterized by comprising the steps of forming an antireflection layer and an antireflection layer on two sides of a glass substrate by magnetron sputtering respectively;
and sputtering a third high refractive index layer on the surface of the reflection increasing layer in a magnetron manner;
the reflection increasing layer comprises a high refractive index layer and a low refractive index layer which are sequentially stacked, and the third high refractive index layer is formed on the surface of the low refractive index layer;
the refractive index of the high refractive index layer and the third high refractive index layer is 2.20-2.72;
the refractive index of the low refractive index layer is 1.46-1.80.
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