Glazing with an optically transparent sensor area

Abstract

The present invention relates to a pane substrate having an optically transparent area, on a surface of the pane, at least one optical device integrated in the optically transparent area, wherein at least one coated glass patch is provided locally between the pane and the optical device. [Selected Figure] Figure 2

Description

[Technical field]

[0001] The present invention relates to a pane substrate, more particularly a glass pane, having an optically transparent sensor area, a method for its manufacture and its use. [Background technology]

[0002] Many automobiles, airplanes, helicopters, and ships are equipped with various optical sensors. Examples of optical sensors are camera systems such as video cameras, night vision cameras, residual light amplifiers, passive infrared detectors such as FUR (forward looking infrared), or infrared-based remote sensing devices such as LiDAR sensing devices. Camera systems can use light in the ultraviolet (UV), visible (VIS), and infrared wavelength ranges (IR).

[0003] In automobiles, these camera systems or infrared-based remote sensing devices, such as LiDAR sensing devices, can be located inside the passenger compartment and behind the windshield, thus providing the ability to detect dangerous situations and obstacles in a timely manner in road traffic.

[0004] Other areas of use of optical sensors include, for example, Electronic Distance Measurement (EDM) using laser range finders, which can determine the distance to other vehicles. Such systems are common in military applications, but also have many possibilities for civilian use. By measuring the distance to the preceding vehicle, it is possible to determine the necessary safety distance and road safety can be significantly improved. Automatic warning systems significantly reduce the risk of rear-end collisions.

[0005] In these glass applications, the glass is most often coated to fulfill its basic functional requirements and / or to provide additional functionality to provide a functionalized glass. Depending on the function provided, the coatings may include anti-reflective (AR) coatings, highly reflective coatings, bandpass filter coatings, tinted coatings, low-E coatings, absorptive coatings (to absorb UV, sound waves, etc.), thermal coatings, hydrophobic coatings, etc.

[0006] When these camera systems or infrared-based sensing devices such as LiDAR sensing devices are used behind a glass pane, more specifically behind a windshield or glass trim elements, it is preferable to have an anti-reflective coating in the optical sensor area, in combination with or without other functional coatings such as tinted and heated coatings. In fact, locally applied coatings are often required in the area where the optical sensor is provided to ensure the best sensor performance. Thus, specific or different coatings are required in small areas of the glazing, rather than the entire surface of the glazing. In this case, a dedicated coating is preferably localized in these small areas and / or is only allowed in these small areas, rather than covering the entire piece of glass pane substrate.

[0007] However, from a process standpoint, it is generally difficult to apply a required coating within limited or small areas of a larger substrate without incurring cost overruns or complicating the manufacturing process. Thus, a need exists for a simple process for applying a particular coating within a small area of ​​a larger substrate.

[0008] For example, automobile glazing is usually designed to block IR light to provide thermal comfort, but when an infrared (IR) sensor (e.g., LiDAR sensor) is integrated behind the automobile glazing (e.g., windshield, sidelight, backlight, and glass trim such as B-pillar) for autonomous driving, the IR sensor works by IR light. In the case of an integrated LiDAR sensor, this must send IR laser light through the automobile glazing to the detection target, and then the IR laser light reflected by the target must pass through the automobile glazing to be collected by the LiDAR sensor. This means that the area where the IR sensor is integrated must have sufficient transparency to IR light. As a result, an AR coating for IR light is required, which must be localized only on the integration area (i.e., the optically transparent area).

[0009] There are also other examples for automotive glazing with the need for localized coatings. In addition to IR sensors, many different kinds of Advanced Driver Assistance System (ADAS) sensors can be integrated onto the automotive glazing. To integrate cameras, a localized heating coating is beneficial because the defrosting function provided can ensure a relatively clear view for the sensor. To integrate radar sensors, the localized coating needs to pass sound waves, while other parts of the automotive glazing absorb sound waves to avoid noise inside the car.

[0010] Also, the above example of localized coating on automotive glazing applies to other vehicles, not just trains, planes, etc., but also other means of transportation, such as drones.

[0011] Furthermore, integrating LiDAR sensors onto large pieces of glass panes such as windshields (sidelights, backlights, and sunroofs) is not only useful for autonomous driving, for example, but can also be applied to displays, touchscreens, architectural glazing (e.g., windows, facades, ceilings, greenhouses, etc.), solar energy applications (photovoltaic and solar thermal panels), the electronics industry (displays and touchscreens), etc. In either case, a localized AR coating for IR light is preferred.

[0012] There are also many other cases where localized coverage on large pieces of glass is useful: in the case of glass roofs, sensors (like rain sensors, light sensors) may be integrated and the integrated areas may need localized coverage to ensure sensor performance; in the case of windows, special functions (e.g. touch sensors) may be added and in this case localized coverage on small areas is needed to meet special requirements of the special functions.

[0013] In the glass industry, there are various coating techniques available, including physical vapor deposition (PVD) methods (such as sputtering deposition and thermal evaporation), chemical deposition methods (such as chemical reduction, pyrolytic coatings such as chemical vapor deposition (CVD), sol-gel deposition), and plasma-assisted chemical vapor deposition (PACVD). These methods are designed to coat major surfaces of glass components, and more generally, substrate components. However, it is very difficult, and in some cases even impossible, to coat small areas of a substrate on a large surface of a substrate, and more specifically, a glass substrate.

[0014] In fact, in the case of online coating techniques such as CVD, the glass is coated during its manufacturing process. In this process, a gaseous chemical mixture is supplied to the surface of the hot glass substrate, which results in a pyrolysis reaction in order to deposit a coating that bonds to the glass. Since this occurs in a furnace, it is only possible to coat the entire glass piece. Furthermore, the bond is very strong and difficult to remove afterwards, so it is not possible to obtain small coated areas while removing the coating from the rest of the part. Therefore, localized coating cannot be achieved.

[0015] In the case of off-line coating techniques such as PVD, chemical reduction, sol-gel deposition, and PACVD, the glass is coated after its manufacturing process by sputtering, spinning, or dipping into it the coating material. While the available techniques are designed to coat the entire glass part, various methods exist to obtain localized coatings, each of which, however, has its own drawbacks.

[0016] A simple method is to coat all of the surface of the glass substrate and then remove the coating from the unwanted parts (e.g. by laser coating stripping) so that the required coating remains only on small areas. The disadvantages of this method are: - The coating process typically requires a vacuum chamber and / or other equipment large enough to hold the entire substrate part, dramatically increasing costs and reducing feasibility. - The coating material removed from the fully coated surface of the substrate to provide the required coverage in the required areas is wasted, which is also a source of expense. The stripping process is an additional process, which results in increased costs and complexity, and is not always possible and often the stripping quality is not guaranteed. - Not useful for techniques that only work on small glass sizes. For example, Radical Assisted Sputtering (RAS) covers glass up to 20cm x 30cm in size. - The second method is to use a mask in the coating process. The mask can block the coating material from reaching the glass substrate so that the coating is dedicated only in a small area. The disadvantages of this method are: the required coating equipment, such as a vacuum chamber, must be large enough to hold the entire piece of glass, which increases the cost and impracticality; the blocked coating material is wasted, which is also a source of cost; the mask is an additional element and is expensive; the alignment between the mask and the glass substrate is an additional step, which induces costs and complexity; it is not useful for techniques that only work for small sized glass.

[0017] The third method is for a coating method using a vacuum chamber. A small vacuum chamber covers only the small area where dedicated coating is required. This reduces the size of the vacuum chamber and avoids waste of coating material, coating stripping process, and coating mask. However, the design of such a chamber can be difficult. The edge of the chamber must be in contact with the glass substrate but must not change the surface quality of the contact area. Also, in case of folded glass substrate (such as WS), the design of the vacuum chamber is difficult and must be changed according to the shape of the glass substrate and the location of the small coated area.

[0018] In the prior art, it is known to mount a plastic patch on a glass substrate, on which a coating scan is provided, in order to provide a localized coating function. However, coating on a plastic patch has the following disadvantages: - Usually the bond between the coating material and the plastic substrate is relatively difficult. - Plastic patches have poor resistance to hazardous conditions in the coating process, e.g. temperature, chemical corrosion, etc. This results in limited coating possibilities. - Plastic patches have a much shorter lifespan. - Plastics have poor resistance to both mechanical and chemical environmental conditions. Summary of the Invention [Problem to be solved by the invention]

[0019] It is therefore an object of the present invention to provide a functionalized glass patch with a dedicated coating for attachment to a larger substrate or without a coating (different from the coating provided on the functionalized glass patch). More particularly, it is an object of the present invention to provide a pane substrate, more particularly a glass substrate, with an optically transparent sensor area disposed behind the pane substrate, that can be easily manufactured from a finished and standardized pane without significant modification. [Means for solving the problem]

[0020] Accordingly, the present invention relates to a pane substrate having at least an optically transparent area, the pane substrate having, on a surface of the pane, at least one optical device integrated within the optically transparent area.

[0021] According to the invention, at least one coated glass patch is provided locally between the pane and the optical device.

[0022] In one particular embodiment, the present invention relates to a functionalized glass patch having a dedicated coating provided within an optically transparent sensor area disposed between the windshield and an optical sensor.

[0023] Thus, although the present invention may be used with glass substrates, the substrates may be plastic substrates, plexiglass substrates, and the like, as well as other materials.

[0024] According to the present invention, the pane substrate may or may not be completely coated or may be partially coated, and if a coating is provided on the surface of the pane substrate, the properties of the coating on the major surface of the pane substrate and the function of the sensor will determine the removal of the coating in the optically transparent area.

[0025] According to the invention, the optical device may be a light source such as a laser, a diode, a sensor such as a LIDAR, a camera, or the like.

[0026] In a preferred embodiment of the invention, the optical device is an optical sensor.

[0027] In accordance with the present invention, the functionalized glass patch can have a single or double sided coating to provide one or more distinct functions in comparison to the primary substrate of the pane substrate to which the glass patch is applied.

[0028] The functionalized glass patch according to the present invention is fixed to the pane substrate, more specifically to the glass substrate. The functionalized glass patch can be fixed during autoclaving of the assembly with the substrate and the functionalized glass patch. Autoclaving is a well-known technique commonly used for automotive glazing. An interlayer (such as PVB, EVA, and others) can be used between the functionalized glass patch and the glass substrate. In case of laminated glass substrates (such as windshields), the functionalized glass patch can be attached when the glass substrate is autoclaved. Another method is to use optical bonding materials (such as 3M materials, AGC Infoverre) to bond the functionalized glass patch to the substrate. There are also many other possible solutions for attachment. Thus, the glass patch is optically and mechanically bonded to the pane substrate, more specifically to the glass substrate, to ensure good adhesion, transparency, and / or clarity.

[0029] In accordance with the present invention, functionalized glass patches can be of any size and shape and can be applied onto large pieces of substrates to provide localized coverage functions.

[0030] According to the present invention, by coating only small pieces of glass, the following benefits are provided: -On-line coating techniques such as CVD can be used. - No large coating equipment (such as a vacuum chamber) is required to hold the entire glass substrate part, thus reducing the cost and increasing the feasibility of coating. - No coating material is wasted, and coating material is saved. - Compatible with the majority of coating techniques, even those that only work on small glass sizes, such as RAS. - No de-coating process is required after coating. - No covering mask required. - Dedicated coating functions such as AR coating and color coating are directly available.

[0031] The glass patch coating provides the following advantages: - An easy bond between the coating material and the glass patch is obtained. - Resistant to most of the coating processes, because glass is resistant to the dangerous process conditions (such as high temperatures and chemical attack). - Glass has a long life. - Glass has strong mechanical and chemical resistance.

[0032] Moreover, proven autoclave assembly processes are directly applicable for installation: thus, the functionalized glass patch can be installed in automotive glazing (such as WS) during the autoclave assembly process for automotive glazing.

[0033] Furthermore, the functionalized glass patch can be made very thin, e.g., less than 1 mm. Therefore, it is not only lightweight and aesthetic, but can also be easily folded to fit the shape of a large substrate. Low-temperature folding of the glass patch also helps reduce surface distortion. Even when folding of the glass patch is not envisaged, a small thickness is preferred because it is aesthetic and lightweight.

[0034] The invention therefore proposes a functionalized glass patch with a dedicated coating to be attached to a substrate (e.g. glass, plastic) so that a localized coating can be achieved. In a preferred embodiment, the optical device is an integrated LiDAR sensor mounted on the windshield of a car.

[0035] A pane with an optically transparent sensor area comprises at least a pane and at least an optically transparent sensor area. In the context of the present invention, the expression "optically transparent sensor area" means a part of the pane that provides the relevant optical and electromagnetic data or signals to the sensor. It may be any part of the pane or an inserted pane segment that has a high transparency of the relevant optical and electromagnetic signals. The optically transparent sensor area preferably occupies less than 10% of the surface of the pane, preferably less than 5%, more preferably less than 2% of the surface of the pane, more preferably less than 1%. For example, in the case of automobile glazing, an optical device, more particularly a Lidar, will be arranged in the optically transparent sensor area. The glass patch arranged between the substrate and the optically transparent sensor comprises at least a coating. In the context of the present invention, the coating may be applied both on the side of the glass patch facing the pane and / or on the side of the glass patch facing away from the paint. The glass patch preferably has a thickness of less than 1 mm, more preferably less than 0.5 mm. The average transmittance of the entire configuration of the sensor area is preferably more than 60%, particularly preferably more than 70%.

[0036] The optical sensor device preferably includes a camera for visible light with wavelengths between 400 nm and 750 nm and infrared light with wavelengths between 750 nm and 1650 nm.

[0037] The pane 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 pane preferably comprises single plane safety glass or laminated safety glass.

[0038] More preferably, the pane substrate is a glass pane.

[0039] More preferably, the glass pane according to the invention has a very low absorption coefficient in the wavelength range of 750 nm to 1650 nm, which is commonly used in the optical technology to which the present invention relates, compared to conventional glasses. -1 Preferably, the glass sheet has an absorption coefficient in the wavelength range of 750 nm to 1650 nm that is lower than that of -1 Less than 2m in some cases -1 Less than 1m, and in some cases even more preferably 1m -1 Less than or in some cases 0.8m -1 has an absorption coefficient less than

[0040] Low absorption gives the added advantage that the final IR transmission is less affected by the optical path within the material, which means that for large Field Of View (FOV) sensors with high aperture angles, the perceived intensity at different angles (images at different areas) will be relatively uniform, especially when the sensor is optically coupled to glazing.

[0041] Thus, when an autonomous vehicle encounters an unforeseen driving environment that is not suitable for autonomous operation, such as road works or obstacles, the sensors through the glazing according to the present invention can capture data regarding the vehicle and the unforeseen driving environment. The captured data can be transmitted to a remote operator or to a central intelligent unit. The remote operator or unit can operate the vehicle or issue commands to the autonomous vehicle to be executed on various vehicle systems. The captured data transmitted to the remote operator / unit can be optimized to conserve bandwidth, such as by transmitting a limited subset of the captured data.

[0042] According to one embodiment of the present invention, the glass pane substrate and the glass patch provided between the glass pane substrate and the optical device have a wavelength of 5 mm or less in the range of 750 nm to 1650 nm. -1 Preferably, the glass sheet has an absorption coefficient of less than 3 m -1 and the optical device is an infrared-based remote sensing device in the wavelength range of 750 to 1650 nm.

[0043] The sensor area preferably has an optical transparency to visible light (VIS) and / or infrared radiation (IR) of >60%, preferably >70%.

[0044] The glass patch preferably comprises flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass. The glass substrate preferably has an optical transparency for visible light and / or infrared radiation (IR) of more than 80%, particularly preferably more than 90%.

[0045] The coating applied on the surface of the glass patch is preferably selected from the group consisting of anti-reflective (AR) coatings, band pass filter coatings, heat coatings, tint coatings, selective coatings (infrared-IR coatings), and anti-fog coatings.

[0046] When the optical device, especially the optical sensor, is an IR-based remote sensing device, and more particularly when the IR-based remote sensing device is a LIDAR, it is preferred to provide an AR coating on the surface in contact with / facing the optical device. The AR coating improves the transmission at the wavelengths of interest. This results in reduced operational problems (e.g., reflection problems, heating problems) and improved sensor performance (e.g., detection range).

[0047] The heat coating preferably has a layer thickness of 0.1 μm to 50 μm, particularly preferably 1 μm to 10 μm.

[0048] The glass patch further includes an optically transparent coating, preferably selected from antistatic, water absorbing, hydrophilic, hydrophobic, or oleophobic and hydrophobic coatings.

[0049] The invention further includes the use of panes having an optical sensor according to the invention in automobiles, ships, airplanes and helicopters.

[0050] The pane with the optical sensor is preferably used as a windshield and / or rear window in a motor vehicle.

[0051] The present invention will now be described in detail with reference to the drawings, which are not intended to limit the present invention in any way.

[0052] For the sake of clarity, in the following description, the numbering of the pane substrate with the glass sheet, or more specifically the glass pane substrate, refers to the numbering system conventionally used for glazing. Thus, the surface of the glazing that is in contact with the environment outside the vehicle is designated as surface 1, and the surface that is in contact with the interior medium, i.e. the passenger compartment, is designated as surface 2. In the case of laminated glazing, the surface of the glass sheet that is in contact with the environment outside the vehicle is designated as surface 1, and the surface that is in contact with the interior part, i.e. the passenger compartment, is designated as surface 4.

[0053] For the avoidance of doubt, the terms "exterior" and "interior" refer to the orientation of the pane substrate, or more particularly, the glass pane substrate, when installed as glazing within a vehicle. [Brief description of the drawings]

[0054] [Figure 1a] FIG. 2 is a plan view of a pane substrate according to the present invention having an optically transparent sensor area according to the present invention. [Figure 1b] 2 is a cross-sectional view of the pane of FIG. 1 having an optically transparent sensor area according to the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of a pane according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] Figures 1a and 1b represent an automobile glazing according to an embodiment of the present invention. The automobile glazing 1 is a laminated glazing with an exterior and an interior glass sheet laminated by at least one thermoplastic interlayer. More specifically, Figures 1a and 1b show a LiDAR sensor 2 as an optical device integrated on a windshield 1. According to the invention, in a front view, the windshield 1 is divided into two zones, where zone 21 is the main surface of the windshield and the optically transparent area 22 corresponds to the invention. On the main surface 21, the windshield is coated with a coating that blocks infrared (IR) light in order to provide thermal comfort inside the vehicle. In the optically transparent area 22, where the LiDAR sensor 2 is integrated, it is necessary to transmit as much of the IR light used as possible in order to ensure optimal performance of the LiDAR sensor. As a result, a localized anti-reflection (AR) coating against IR light in the optically transparent area 22 allows the LiDAR sensor to function relatively efficiently. According to the invention, the LiDAR 2, or more generally the optical device, will be provided in the inner face of the inner glass sheet, also called face 4.

[0056] According to the invention, several optical devices, including optical sensors, may be provided on the substrate. In this case, the number of glasses to be patched must be adapted accordingly. It is understood that if the optical devices are different, the coating must be adapted accordingly.

[0057] Thus, according to the invention, a functionalized, coated glass patch is provided between the windshield 1 and the LiDAR sensor 2, as represented in FIG.

[0058] 2 shows the layer structure of a windshield 1 integrated with a LiDAR sensor 2 according to an embodiment of the present invention. A conventional windshield has a laminate structure, which has two glass sheets as the pane substrate, an outer glass sheet 25 and an inner glass sheet 26, laminated together by an intermediate layer 27.

[0059] According to the invention, a functionalized glass patch 100 is mounted in the optically transparent area 22 of the windshield 1 in which the optical device is to be fixed.

[0060] According to the invention, the glass patch 100 may consist of soda-lime glass, aluminosilicate glass, borosilicate glass or other glass as appropriate. The glass patch 100 may be coated on one or both sides 101, 102 to provide one or more coating functions. When an IR remote device, more particularly a LiDAR, is used as the optical device, a coating 101, such as an anti-reflection coating for IR light, is highly recommended to be used on the surface facing the optical device to ensure good performance of the LiDAR. The other side of the glass patch 100 facing the outer surface of the inner glass sheet (also called face 4) can be coated with a coating 102 with another function, such as a colored coating, so as to be aesthetic, or with any other coating that does not affect the performance of the LiDAR, or more generally the optical device. The fixing of the functionalized glass patch 100 to the inner surface of the inner glass sheet in the optically transparent area 22 can be performed by autoclave assembly using an interlayer 103 (such as PVB, EVA, and others), or by optical bonding using a special material 103 (such as 3M materials, AGC Infoverre), or by other methods suitable for fixing the glass patch to the pane substrate. It is understood that the above-mentioned methods of fixing the functionalized glass patch 100 can be used in the case of monolithic glass pane substrates, or plastic pane substrates, or mixtures thereof, as appropriate. The thickness of the glass patch may preferably be thin, i.e., less than 1 mm. A thin glass pane can be folded relatively easily to fit the shape of the windshield 1 or pane substrate. In addition to this, a thin glass patch is lightweight and aesthetically pleasing.

[0061] The edges of the functionalized glass patch can be easily concealed and sealed by the bracket 28 that holds the LiDAR system.

[0062] It should be noted that the above-mentioned applications of the functionalized glass patch are only examples for illustrative purposes. Thus, the glass patch can have different covering functions and can be attached to any substrate of many materials and different shapes. It should also be understood that the pane substrate can be a trim element, more specifically a glass trim element, a sidelight, etc.

Claims

1. A pane substrate having an optically transparent area (22), the pane substrate having on a surface thereof at least one optical device (2) integrated within the optically transparent area (22), A pane substrate, characterized in that at least one coated glass patch (100) is provided locally between said pane (1) and said optical device (2), said optically transparent area (22) having an optical transparency to infrared radiation of >60%, and said optical device (2) being an infrared-based remote sensing device (LIDAR sensor) in the wavelength range of 750 nm to 1650 nm.

2. 2. A pane (1) according to claim 1, comprising glass and / or polymers, such as flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass or polymethylmethacrylate, and / or mixtures thereof.

3. 2. The pane (1) of claim 1, wherein the glass patch (100) comprises glass, such as flat glass, float glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass, or mixtures thereof.

4. 2. A pane (1) according to claim 1, wherein said glass patch (100) is provided with at least one coating (101, 102) chosen from the group consisting of an anti-reflective coating, a tint coating, a heat coating, a band-pass coating and an anti-fog coating.

5. The pane (1) according to claim 1, wherein the glass patch (100) is optically and mechanically coupled to the substrate.

6. 2. The pane (1) according to claim 1, wherein the glass patch (100) has a thickness of <1 mm.

7. 6. A pane (1) according to claim 5, wherein the coatings (101, 102) are provided on the face of the glass patch (100) facing the pane and / or on the face of the glass patch (100) not facing the pane.

8. A pane (1) according to any one of the preceding claims, wherein the pane is an automobile glazing.

9. The pane substrate and the glass patch (100) have a wavelength range of 750 nm to 1650 nm and a resolution of 5 m. －１ A pane (1) according to any one of the preceding claims, having an absorption coefficient less than

10. A pane (1) according to any one of the preceding claims, wherein a glass patch (100) is provided on the inner face, the size of said glass patch being adapted to the size of the field of view of said optical device (2).

11. 11. The pane of claim 1, wherein the optically transparent sensor area (22) occupies less than 10% of the surface of the pane substrate.

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