Glazing with optically transparent sensor region

Abstract

A glazing with an optically transparent sensor region is disclosed. The invention relates to a panel substrate having an optically transparent region, the panel substrate comprising at least one optical device integrated in the optically transparent region on a surface of the panel. According to the invention, at least one coated glass patch is locally provided between the panel and the optical device.

Description

[0001] This application is a divisional application of Chinese invention patent application No. 201980044265.2, filed on July 3, 2019, entitled "Embedded glass with an optically transparent sensor region". Technical Field

[0002] The present invention relates to a panel substrate, and more particularly to a glass panel having an optically transparent sensor region, a method for producing the glass panel, and the use of the glass panel. Background Technology

[0003] Many motor vehicles, aircraft, helicopters, and ships are equipped with various optical sensors. Examples of optical sensors are camera systems (such as video cameras and night vision cameras), residual light amplifiers, passive infrared detectors (such as FUR (forward-looking infrared)), or infrared-based remote sensing devices (such as lidar sensors). Camera systems can use light in the ultraviolet (UV), visible (VIS), and infrared wavelength ranges (IR).

[0004] In motor vehicles, these camera systems or infrared-based remote sensing devices (such as lidar sensors) can be placed inside the passenger compartment behind the windshield. Therefore, even in road traffic, these systems or devices can detect hazards and obstacles in a timely manner.

[0005] Other areas where optical sensors are used include electronic distance measurement (EDM), such as using laser rangefinders. This allows for the determination of distances to other motor vehicles. While common in military applications, this system also has numerous civilian potential. By measuring the distance to the vehicle in front, necessary safety distances can be determined, significantly improving traffic safety. Using automatic warning systems, the risk of rear-end collisions can be significantly reduced. Summary of the Invention

[0006] In these glass applications, the glass is often coated to achieve its basic functional requirements and / or to provide additional functions to provide functionalized glass. Depending on the function it provides, coatings can include antireflective (AR) coatings, high-reflective coatings, bandpass filter coatings, colored coatings, low-E coatings, absorptive coatings (for absorbing UV, sound waves, etc.), heat-absorbing coatings, hydrophobic coatings, etc.

[0007] When these camera systems or infrared-based remote sensing devices (such as lidar sensors) are used behind glass panels, and more specifically behind windshields or glass decorative elements, it is preferable to have an anti-reflective coating in the optical sensor area, with or without another functionalized coating (such as a colored coating and a heat-generating coating). In practice, sometimes a locally applied coating is required in the area where the optical sensor is located to ensure optimal sensor performance. Therefore, specific or different coatings are needed on smaller areas of the glass panel compared to the entire surface of the panel. In such cases, it is desirable and / or permissible to position the specialized coating only in these smaller areas, rather than covering the entire glass panel substrate.

[0008] However, in terms of process, it is often difficult to apply the required coating to a limited or small area in a large substrate without increasing costs or complicating the manufacturing process. Therefore, a simplified process for applying a specific coating to a small area in a large substrate is needed.

[0009] For example, when infrared (IR) sensors (such as lidar sensors) are integrated behind automotive glass panels (e.g., windshields, side windows, rear windows, and glass trim such as B-pillars) for autonomous driving, these panels are typically designed to block IR light to provide thermal comfort. However, IR sensors utilize IR light to operate. For integrated lidar sensors, they must emit IR laser light that passes through the automotive glass to reach the target, and the IR laser light reflected from the target must then pass through the glass to be collected by the lidar sensor. This means the area where the IR sensor is integrated must have sufficient transmittance for IR light. Therefore, an AR coating for IR light is required, and this coating must be positioned only on the integration area, i.e., the optically transparent area.

[0010] Other examples exist of automotive glass requiring localized coatings. Besides IR sensors, many different types of Advanced Driver Assistance Systems (ADAS) sensors can also be integrated into automotive glass. For camera integration, localized heated coatings are beneficial because the provided defrosting function ensures a clearer view for the sensor. For radar sensor integration, localized coatings may be needed to transmit sound waves, while other parts of the automotive glass absorb the sound waves to avoid noise inside the vehicle.

[0011] The above examples of localized coatings on automotive glass also apply to other modes of transportation (such as trains, airplanes, etc.), and even to other vehicles (such as drones).

[0012] Furthermore, integrating LiDAR sensors onto large glass panels (such as windshields (side windows, rear windows, and sunroofs)) is not only useful for autonomous driving, but also applicable to displays, touchscreens, architectural glazing (e.g., windows, facades, roofs, and greenhouses), solar energy applications (photovoltaics and solar thermal panels), and the electronics industry (displays and touchscreens) to provide additional functionalities such as 3D recognition and facial ID. In any case, a localized AR coating for IR light is preferred.

[0013] There are many other situations where localized coatings on large panes of glass would be useful. For glass roofs, sensors (such as rain sensors, light sensors, etc.) may be integrated, and the integrated area might require localized coatings to ensure sensor performance. For windows, special functions may be added (such as touch sensors), in which case there is a specific need for localized coatings on smaller areas to achieve those functions.

[0014] In the glass industry, various coating techniques are available, including physical vapor deposition (PVD) methods (such as sputtering deposition and thermal vapor deposition), chemical deposition methods (such as chemical reduction, pyrolytic coatings (such as chemical vapor deposition (CVD) and sol-gel deposition)), and plasma-assisted chemical vapor deposition (PACVD). However, these methods are designed to coat the main surface of a piece of glass or more generally a substrate. However, compared to the larger surface area of ​​the substrate, and more specifically, the glass substrate, it is difficult or even impossible to coat smaller areas within the substrate.

[0015] In practice, for in-line coating technologies such as CVD, the glass is coated during its manufacturing process. In this process, a gaseous chemical mixture is directed onto the surface of a heated glass substrate, where a pyrolysis reaction occurs to deposit a coating bonded to the glass. Because this happens in a furnace, only the entire piece of glass can be coated. Furthermore, the bond is very strong and difficult to remove afterward, making it impossible to retain a small coated area while simultaneously removing the coating from other areas. Therefore, localized coating is not possible.

[0016] For offline coating techniques such as PVD, chemical reduction, sol-gel deposition, and PACVD, glass is coated post-manufacturing by sputtering, spraying, spinning, or immersion in a coating material. While available techniques are designed to coat entire sheets of glass, different methods exist for achieving localized coatings. However, each method has its own drawbacks.

[0017] One straightforward method is to coat all surfaces of the glass substrate and then remove the coating from the unwanted areas (e.g., by laser decoating), leaving only a small area with the desired coating. The disadvantage is:

[0018] - Coating processes typically require vacuum chambers and / or other equipment large enough to accommodate the entire substrate. This significantly increases costs and reduces feasibility;

[0019] Removing coating material from the fully coated surface of the substrate to provide the required coating in the required area is wasteful and a source of cost.

[0020] - The coating removal process is an additional step, which increases cost and complexity. Furthermore, this process is not always possible, and sometimes the quality of the coating removal cannot be guaranteed;

[0021] This is not applicable to techniques that are only suitable for small-sized glass. For example, the glass size that can be coated by Raised Assisted Sputtering (RAS) is 20 cm by 30 cm.

[0022] - The second method is to use a mask in the coating process. A mask blocks the coating material from reaching the glass substrate, allowing the coating to be applied only to a smaller area. The disadvantages are as follows: the required coating facilities (such as a vacuum chamber) must be large enough to accommodate the entire glass, increasing cost and feasibility; the blocked coating material is wasted, also a source of cost; the mask is an additional and expensive component; alignment between the mask and the glass substrate is an extra step, adding cost and complexity; and this is not feasible for techniques that only work with small-sized glass.

[0023] The third method is a vacuum chamber coating approach. A small vacuum chamber covers only the smaller area requiring a specialized coating. This method reduces the size of the vacuum chamber and avoids waste of coating material, stripping processes, and coating masks. However, designing such a vacuum chamber can be challenging. The edges of the vacuum chamber must contact the glass substrate without altering the surface quality of the contact area. Furthermore, for curved glass substrates (such as WS), vacuum chamber design is more difficult and must be tailored to the shape of the glass substrate and the location of the smaller coating area.

[0024] As is known in the prior art, coated plastic patches can be attached to glass substrates to provide localized coating functionality. However, coating on plastic patches has the following disadvantages:

[0025] - The bonding between the coating material and the plastic substrate is usually more difficult;

[0026] - Plastic patches have low tolerance to critical conditions (such as high temperature, chemical corrosion, etc.) during the coating process, which limits the possibilities of coating.

[0027] - The lifespan of plastic patches is much shorter;

[0028] - Plastics have low tolerance to both mechanical and chemical environmental conditions.

[0029] Therefore, the object of the present invention is to provide a functionalized glass patch with a special coating, which is attached to a relatively large substrate having a coating (different from the coating provided on the functionalized glass patch) or no coating. More specifically, the object of the present invention is to provide a panel substrate, and more specifically a glass substrate, having an optically transparent sensor region disposed thereback, which can be easily produced from a finished standardized panel without major modifications.

[0030] Therefore, the present invention relates to a panel substrate having at least an optically transparent region, the panel substrate including at least one optical device integrated in the optically transparent region on the surface of the panel.

[0031] According to the present invention, at least one coated glass patch is partially disposed between the panel and the optical device.

[0032] In a particular embodiment of the invention, the invention relates to a functionalized glass patch having a special coating, disposed in an optically transparent sensor area, and placed between a windshield and an optical sensor.

[0033] Therefore, the present invention can be used on glass substrates, but the substrate can also be other materials such as plastic substrates, plexiglass substrates, etc.

[0034] According to the present invention, the panel substrate may be completely coated, uncoated, or partially coated. If a coating is provided on the surface of the panel substrate, the nature of the coating on the main surface of the panel substrate and the function of the sensor will determine the removal of the coating in the optically transparent area.

[0035] According to the present invention, the optical device may be a light source, such as a laser, a diode, a sensor (such as a lidar), a camera, etc.

[0036] In a preferred embodiment of the present invention, the optical device is an optical sensor.

[0037] According to the present invention, compared with the main substrate of the panel substrate on which the glass patch is provided, the functionalized glass patch may have a single-sided coating or a double-sided coating to provide one or more different functions.

[0038] The functionalized glass patch according to the invention is fixed to a panel substrate, and more specifically, to a glass substrate. The functionalized glass patch can be fixed during autoclaving of the assembly comprising the substrate and the functionalized glass patch. Autoclaving is a well-known technique commonly used in automotive glass panels. A laminate (such as PVB, EVA, etc.) can be used between the functionalized glass patch and the glass substrate. In the case of laminated glass substrates (such as windshields), the functionalized glass patch can be attached simultaneously with autoclaving the glass substrate. Another method is to use optical bonding materials (such as 3M materials, AGC Infoverre) to bond the functionalized glass patch to the substrate. Many other possible solutions for attachment also exist. Thus, the glass patch is optically and mechanically bonded to the panel substrate, and more specifically, the glass substrate, to ensure good adhesion, transparency, and / or clarity.

[0039] According to the present invention, the functionalized glass patch can have any size and shape, and can be applied to a bulk substrate to provide localized coating functionality.

[0040] As a result of the present invention, the following advantages are provided by coating only small pieces of glass:

[0041] - In-line coating technologies (such as CVD) can be used.

[0042] - No large coating facilities (such as vacuum chambers) are required to hold the entire glass substrate. Therefore, costs are reduced and coating feasibility is increased.

[0043] - It saves coating material without causing waste.

[0044] - Applicable to most coating technologies, even those that are only suitable for small-sized glass (such as RAS).

[0045] - No coating removal process is required after coating.

[0046] - No mask is required

[0047] - Dedicated coating functions are readily available, such as AR coating and colored coating.

[0048] Coating glass patches offers the following advantages:

[0049] - Enables easy bonding between the coating material and the glass patch.

[0050] - It is resistant to most coating processes because the glass can tolerate critical process conditions such as high temperature and chemical corrosion.

[0051] - Glass has a long service life.

[0052] Glass has strong mechanical and chemical resistance.

[0053] Furthermore, proven autoclaving assembly processes can be directly applied to attachment. Therefore, functionalized glass patches (such as WS) can be attached to automotive pre-fitted glass during the autoclaving assembly process used for automotive pre-fitted glass.

[0054] Furthermore, functionalized glass patches can be very thin, for example, less than 1 mm. Therefore, functionalized glass patches are not only lightweight and aesthetically pleasing, but can also be easily bent to fit the shape of large substrates. Cold bending of the glass patch also helps reduce surface deformation. Even if bending the glass patch is not intended, a thinner thickness would be preferable from both aesthetic and lightweight perspectives.

[0055] Therefore, this invention proposes a functionalized glass patch with a specialized coating, which is attached to a substrate (e.g., glass, plastic) to enable localized coating. In a preferred embodiment, the optical device is an integrated lidar sensor attached to an automotive windshield.

[0056] A panel having an optically transparent sensor region comprises at least a panel and at least an optically transparent sensor region. In the context of this invention, the term "optically transparent sensor region" refers to a portion of the panel that provides relevant optical and electromagnetic data or signals to the sensor. This region can be any part of the panel or an insert panel segment with high transmittance for the relevant optical and electromagnetic signals. The optically transparent sensor region preferably occupies less than 10%, preferably less than 5%, more preferably less than 2%, and even more preferably less than 1% of the panel surface. For example, in automotive embedded glass, optical devices, and more specifically lidar, will be placed in the optically transparent sensor region. A glass patch disposed between the substrate and the optically transparent sensor comprises at least one coating. In the context of this invention, the coating may be applied to the panel-facing side of the glass patch and / or also to the panel-removing side of the glass patch. The thickness of the glass patch is preferably less than 1 mm, more preferably less than 0.5 mm. The average transmittance of the entire arrangement of the sensor region is preferably greater than 60%, particularly preferably greater than 70%.

[0057] The optical sensor device preferably includes a camera for visible light with wavelengths from 400 nm to 750 nm and infrared light with wavelengths from 750 nm to 1650 nm.

[0058] The panel substrate preferably comprises glass and / or polymer, preferably flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, polymethyl methacrylate and / or mixtures thereof. The panel preferably comprises single-pane safety glass or laminated safety glass.

[0059] More preferably, the panel substrate is a glass panel.

[0060] More preferably, compared to conventional glass, the glass panel according to the invention has a very low absorption coefficient in the wavelength range of 750 nm to 1650 nm (typically used in optical technologies involving the invention). In particular, the glass sheet according to embodiments of the invention has an absorption coefficient of less than 5 μm in the wavelength range of 750 nm to 1650 nm. -1 The absorption coefficient is [value missing]. Preferably, the glass sheet has an absorption coefficient of less than 3 μm. -1 or even below 2 m -1 And even more preferably less than 1 m -1 or even below 0.8 m -1 The absorption coefficient.

[0061] Low absorption offers the added advantage that the final IR transmittance is less affected by the optical path length in the material. This means that for sensors with a large field of view (FOV) and a high angle of divergence, the perceived intensity (the image in different regions) will be more uniform across various angles, especially when the sensor optics are optically coupled to the mounting glass.

[0062] Therefore, when an autonomous vehicle encounters unexpected driving environments unsuitable for autonomous operation, such as road construction or obstacles, the embedded glass vehicle sensor according to the invention can capture data about the vehicle and the unexpected driving environment. The captured data can be sent to a remote operator or a central intelligent unit. The remote operator or unit can operate the vehicle or issue commands to the autonomous vehicle to execute on various vehicle systems. The captured data sent to the remote operator / unit can be optimized to save bandwidth, such as by sending a finite subset of the captured data.

[0063] According to an embodiment of the present invention, the glass panel substrate and the glass patch disposed between the optical device have a wavelength range of less than 5 nm in the wavelength range of 750 nm to 1650 nm. -1 The absorption coefficient, preferably, is less than 3 μm for the glass sheet. -1 The absorption coefficient is [value missing], and the optical device is an infrared-based remote sensing device in the wavelength range of 750 nm to 1650 nm.

[0064] The optical transparency of the sensor area to visible light (VIS) and / or infrared radiation (IR) is preferably > 60% and preferably > 70%.

[0065] The glass patch preferably comprises flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, or aluminosilicate glass. The optical transparency of the glass substrate to visible light and / or infrared radiation (IR) is preferably greater than 80%, and particularly preferably greater than 90%.

[0066] The coating applied to the surface of the glass patch is preferably selected from the following: anti-reflective (AR) coating, bandpass filter coating, heating coating, colored coating, selective coating (infrared-IR coating), anti-fog coating, etc.

[0067] When the optical device, specifically when the optical sensor is an IR-based remote sensing device, and more specifically when the IR-based remote sensing device is a lidar, preferably an AR coating is provided on the side of the glass patch that contacts / faces the optical device. The AR coating enhances the transmittance at the wavelength of interest, which reduces operational problems (e.g., reflection problems, heating problems) and improves sensor performance (e.g., detection range).

[0068] The thickness of the heat-conducting coating is preferably from 0.1 μm to 50 μm, and particularly preferably from 1 μm to 10 μm.

[0069] The glass patch preferably further comprises an optically transparent coating selected from the following: an antistatic coating, a water-absorbing coating, a hydrophilic coating, a hydrophobic coating, or an oleophobic and hydrophobic coating.

[0070] The invention further includes the use of a panel with an optical sensor according to the invention in motor vehicles, ships, airplanes and helicopters.

[0071] Panels with optical sensors are preferably used as windshields and / or rear windows of motor vehicles. Attached Figure Description

[0072] The invention is explained in detail below with reference to the accompanying drawings. The drawings are not intended to limit the invention in any way.

[0073] For simplicity, in the following description, the numbering of the panel substrate, or more specifically the numbering of the glass panel substrate including the glass sheet, refers to the numbering conventionally used for mounting glass. Therefore, the surface of the mounting glass that contacts the vehicle's external environment is referred to as side 1, and the surface that contacts the internal medium (i.e., the passenger compartment) is referred to as surface 2. For laminated mounting glass, the glass sheet that contacts the vehicle's external environment is referred to as side 1, and the surface that contacts the internal portion, i.e., the passenger compartment, is referred to as surface 4.

[0074] To avoid confusion, the terms “external” and “internal” refer to the orientation of the panel substrate or more specifically the glass panel substrate during installation as an embedded glass in a vehicle.

[0075] Figure 1a This is a plan view of a panel substrate according to the present invention, the panel substrate having an optically transparent sensor region according to the present invention.

[0076] Figure 1b yes Figure 1a A cross-section of a panel having an optically transparent sensor region according to the invention.

[0077] Figure 2 This is a cross-section of the panel according to an embodiment of the present invention. Detailed Implementation

[0078] According to an embodiment of the present invention, Figure 1a and Figure 1b This refers to automotive embedded glass. Automotive embedded glass 1 is a laminated embedded glass comprising an outer glass sheet and an inner glass sheet laminated with at least one thermoplastic interlayer. More specifically, Figure 1a and Figure 1b A lidar sensor 2, integrated as an optical device, is shown on a windshield 1. According to the invention, viewed from the front, the windshield 1 is divided into two areas: area 21 is the main surface of the windshield, and the optically transparent area 22 corresponds to the area according to the invention. For the main surface 21, the windshield is coated with a coating that blocks infrared (IR) light to provide thermal comfort for the vehicle interior. In the optically transparent area 22 where the lidar sensor 2 is integrated, it is necessary to transmit as much IR light as possible to ensure optimal performance of the lidar sensor. Therefore, a local anti-reflective (AR) coating for IR light within the optically transparent area 22 will allow the lidar sensor to operate more efficiently. According to the invention, the lidar 2, and more generally the optical device, will be disposed in the inner surface (also referred to as surface 4) of the inner glass sheet.

[0079] According to the present invention, several optical devices, including optical sensors, can be disposed on the substrate; therefore, in this case, the number of glass plates to be attached should be adapted accordingly. It should be understood that if the optical devices are different, the coating should be adapted accordingly.

[0080] Therefore, according to the art, such as Figure 2 As described, a functional coated glass patch is provided between the windshield 1 and the lidar sensor 2.

[0081] Figure 2 The diagram illustrates the layered structure of a windshield 1 integrating a lidar sensor 2 according to an embodiment of the present invention. Conventional windshields have a laminated structure comprising two glass sheets—an outer glass sheet 25 and an inner sheet 26—laminated together by an interlayer 27 as a panel substrate.

[0082] According to the present invention, a functionalized glass patch 100 is attached to the optically transparent area 22 of the windshield 1, and the optical device is fixed in the optically transparent area.

[0083] According to the invention, the glass patch 100 can be made of soda-lime glass, aluminosilicate glass, borosilicate glass, or other glass as required. Either or both sides 101, 102 of the glass patch 100 can be coated to provide one or more coating functions. When an IR remote sensing device, and more specifically a lidar, is used as an optical device, a coating 101 (such as an anti-reflective coating) for the IR light used on the surface facing the optical device is strongly recommended to ensure good performance of the lidar. The other side of the glass patch 100, the outer side of the inward-facing glass sheet (also referred to as side 4), can be coated with another functionalized coating 102, such as a colored coating for aesthetic purposes or any coating that has no effect on the lidar and, more generally, on the optical device. The functionalized glass patch 100 can be fixed to the inner surface of the inner glass sheet in the optically transparent area 22 by: autoclaving assembly using a sandwich 103 (such as PVB, EVA, etc.), optical bonding using a special material 103 (such as 3M material, AGC Infoverre), or other methods suitable for fixing the glass patch to the panel substrate. It should be understood that the methods for fixing the functionalized glass patch 100 described above can be used for monolithic glass panel substrates or plastic panel substrates or a mixture thereof (if applicable). The thickness of the glass patch can preferably be very thin, i.e., less than 1 mm. Thin glass patches can be more easily bent to fit the shape of the windshield 1 or the panel substrate. Furthermore, thin glass patches are lightweight and aesthetically pleasing.

[0084] The edges of the functional glass patch can be easily hidden and sealed by the bracket 28 that secures the lidar system.

[0085] It should be mentioned that the above-described applications of functionalized glass patches are merely illustrative examples. Furthermore, these glass patches can have different coating functions and can be attached to any substrate with various materials and shapes. It should also be understood that the panel substrate can be a decorative element, more specifically a glass decorative element, a side window, etc.

Claims

1. A panel substrate having an optically transparent region (22), the panel substrate including at least one optical device (2) integrated in the optically transparent region (22) on the surface of the panel, wherein the optically transparent region (22) occupies less than 10% of the surface of the panel substrate, wherein the optical sensor (2) is an infrared-based remote sensing device in the wavelength range of 750 nm to 1650 nm. Its features are, At least one glass patch (100) is partially attached to the panel substrate and aligned with the optically transparent area (22), wherein the glass patch (100) has a coating specifically for the optical device (2).

2. The panel substrate according to claim 1, wherein, The glass patch (100) is disposed on the inner surface of the panel substrate, and the size of the glass patch is matched with the size of the field of view of the optical device (2).

3. The panel substrate according to claim 1, wherein, The glass patch (100) is provided with at least one coating (101, 102) selected from the following: anti-reflective coating, colored coating, heating coating, bandpass coating, and anti-fog coating.

4. The panel substrate according to claim 1, wherein, The glass patch (100) is optically and mechanically bonded to the substrate by means of high-pressure sterilization assembly using a sandwich or by means of optical bonding material.

5. The panel substrate according to claim 1, wherein, The glass patch (100) has a thickness of less than 1 mm, preferably less than 0.5 mm.

6. The panel substrate according to claim 1, wherein, The coating (101, 102) is disposed on the side of the glass patch (100) facing the panel and / or on the side of the glass patch (100) away from the panel, more preferably, the coating (101) is disposed on the side of the glass patch away from the panel.

7. The panel substrate according to claim 1, wherein, The edge of the glass patch (100) is hidden and sealed by the bracket (28) that holds the optical sensor (2).

8. The panel substrate according to claim 1, wherein, The glass patch (100) has a wavelength range of less than 5 nm in the wavelength range from 750 nm to 1650 nm. -1 The absorption coefficient.

9. The panel substrate according to any one of claims 1 to 8, wherein, The panel comprises glass and / or polymers, such as flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass, or polymethyl methacrylate and / or mixtures thereof.

10. The panel substrate according to any one of claims 1 to 8, wherein, The glass patch (100) includes glass, such as flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass, or mixtures thereof.

11. The panel substrate according to any one of claims 1 to 8, wherein, The optically transparent region (22) has an optical transparency of more than 60% for infrared radiation.

12. The panel substrate according to any one of the preceding claims, wherein, The panel is automotive-grade glass.

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