COATED GLASS ARTICLE

A coated glass article and a method for its production is disclosed. One or more coatings and layers are applied onto or disposed between a pair of glass sheets to produce such coated glass article that enhances an accuracy and reliability of a heads-up-display system and an optical sensor coupled thereto. More particularly, the coated glass article includes an antireflective layer to facilitate a light transmission of at least 80% for a plurality of wavelengths through the coated glass article and a visible light reflective layer to enhance a visible light reflectance of the coated glass article to between 8.0% and 10.0%.

The subject matter of the embodiments described herein relates generally to a glass article and, more particularly, to a coated glass article that optimizes infrared light transmission and visible light reflection.

A conventional glass article typically comprises either monolithic glass or a laminated glazing. A monolithic glass article consists of a single piece of glass that can be enhanced through additional processes for insulating capabilities, design improvements, and added strength. Normally, the monolithic glass article may be used in building skylights and windows. On the contrary, a laminated glazing glass article typically comprises two glass sheets joined together by an adhesive interlayer. The adhesive interlayer may be produced from certain materials such as polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), or Thermoplastic Polyurethane (TPU), for example, which causes the glass sheets to shatter into smaller, less hazardous pieces when the laminated glazing glass article is broken. Such beneficial feature allows the laminated glazing glass article to be utilized in applications where there is a possibility of human exposure, such as automobile windshields and windows.

An ability to control a light transmission and light reflection of the glass article also makes it suitable for certain applications where certain amounts of light and/or heat radiation through and light reflection of the glass article are desired. One such application is for a windshield used in motor vehicles.

Commercial and passenger vehicles are being designed to use technology such as head-up-display (HUD) systems and sensors, for example, to increase safety, road capacity, and fuel efficiency while reducing pollution, driver stress, and operating costs. The HUD system displays information projected onto the glass article (e.g. the vehicle windshield) reflecting towards a driver or observer, providing the driver of the vehicle with relevant information, without having to look away from the forward field of vision of the vehicle.

These vehicles are also designed to detect surroundings using various sensors including, but not limited to optical sensors such as radar, LIDAR (Light Detection And Ranging), GPS, Odometry, and computer vision, for example. Typically, the optical sensor is mounted on an interior surface of the glass article to provide a suitable position for geometrical distance estimation, an enhanced view of a road surface and traffic situation, and a controlled environment to operate the optical sensor. However, the optical sensors require an increased infrared light transmission and are therefore not fully compatible with conventional glass article configurations.

Currently, the prior art glass articles employed as vehicle windshields either provide an insufficient amount of infrared light with enough intensity to be transmitted through the windshield for proper operation and performance of the LIDAR sensor, or when the prior art glass articles are treated, such as with an antireflective coating to increase the infrared light transmission for proper operation and performance of the LIDAR sensor, the visible light reflection of the glass articles is not sufficient for proper operation and performance of the HUD system.

Accordingly, it would be desirable to produce a glass article including at least one coating that optimizes the infrared light transmission therethrough for proper operation and performance of an optical sensor, while maintaining sufficient visible light reflection for proper operation and performance of a HUD system.

In concordance and agreement with the present disclosure, a glass article including at least one coating that optimizes the infrared light transmission therethrough for proper operation and performance of an optical sensor, while maintaining sufficient visible light reflection for proper operation and performance of a HUD system, has surprisingly been discovered.

In one embodiment, a coated glass article, comprises: a first glass sheet; an antireflective layer disposed adjacent at least a portion of the first glass sheet; and a visible light reflective layer disposed over at least a portion of the antireflective layer, the visible light reflective layer having a refractive index of at least 1.6 and a thickness of no more than 30 nm, wherein the coated glass article exhibits a light transmission of at least 80% for at least one wavelength of infrared light and a visible light reflectance of between about 8% and 10%.

As aspects of certain embodiments, the first glass sheet is produced from a generally low-light absorption, high-light transmission glass material.

As aspects of certain embodiments, the glass material has an iron content less than 100 ppm, preferably 10 ppm or less.

As aspects of certain embodiments, further comprises a second glass sheet, wherein the first and second glass sheets are joined together by an adhesive layer. As aspects of certain embodiments, the adhesive layer includes at least one ply of at least one of polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyvinyl chloride (PVC), polyurethane (PU), acoustic modified PVB and Uvekol® (a liquid curable acrylic resin).

As aspects of certain embodiments, the adhesive layer comprises a plurality of plies.

As aspects of certain embodiments, the adhesive layer includes a first ply formed of PVB, a second ply formed of polyethylene terephthalate (PET), and a third ply formed of PVB.

As aspects of certain embodiments, the second glass sheet is produced from a generally low-light absorption, high-light transmission glass material.

As aspects of certain embodiments, this glass material has an iron content less than 100 ppm, preferably 10 ppm or less.

As aspects of certain embodiments, the coated glass article further comprises at least one reflecting layer. The reflecting layer may be a solar and/or infrared reflecting layer.

As aspects of certain embodiments, the at least one reflecting layer is disposed adjacent at least a portion of one of the first sheet and the second sheet.

As aspects of certain embodiments, the at least one reflecting layer is incorporated into a multi-ply interlayer.

As aspects of certain embodiments, the glass article may include a plurality of reflecting layers disposed adjacent at least one of the first and second glass sheets and incorporated into a multi-ply layer.

As aspects of certain embodiments, the at least one reflecting layer comprises a metal material.

As aspects of certain embodiments, the at least one reflecting layer includes at least one void formed therein.

As aspects of certain embodiments, the antireflective layer is formed to cover at least a portion of at least one of the first and second sheets.

As aspects of certain embodiments, each of the first sheet and the second sheet includes a first major surface and a second major surface, and wherein the antireflective layer is disposed adjacent at least a portion of the second major surface of the second sheet.

As aspects of certain embodiments, the antireflective layer has a thickness of at least 80 nm.

As aspects of certain embodiments, the antireflective layer has a thickness in a range of about 120 nm to about 200 nm.

As aspects of certain embodiments, the antireflective layer is formed of silicon dioxide (SiO2).

As aspects of certain embodiments, the antireflective layer facilitates a light transmission of at least 94% for the at least one wavelength through the coated glass article.

As aspects of certain embodiments, the at least one wavelength is in a range of about 750 nm to about 1 mm.

As aspects of certain embodiments, the antireflective layer facilitates a desired light transmission for at least one of a first wavelength and a second wavelength.

As aspects of certain embodiments, the first wavelength is about 905 nm.

As aspects of certain embodiments, the second wavelength is about 1550 nm.

As aspects of certain embodiments, further comprising an optical sensor disposed adjacent at least one of the antireflective layer and the visible light reflective layer, wherein the optical sensor is configured to emit a light beam having the at least one wavelength.

As aspects of certain embodiments, wherein the optical sensor is positioned in alignment with a void formed in the at least one reflecting layer of the coated glass article.

As aspects of certain embodiments, the visible light reflective layer is formed to cover at least a portion of the coated glass article.

As aspects of certain embodiments, the visible light reflective layer has a thickness in a range of about 6 nm to about 9 nm.

As aspects of certain embodiments, the visible light reflective layer is a metal oxide having a refractive index of at least 1.6 and less than 1.8 and a thickness of no more than 30 nm.

As aspects of certain embodiments, the visible light reflective layer is a metal oxide having a refractive index of at least 1.8 and a thickness of no more than 20 nm. As aspects of certain embodiments, the visible light reflective layer is formed of tin oxide (SnO2).

As aspects of certain embodiments, the visible light reflective layer facilitates a visible light reflectance value of about 8.6% at an exterior surface of the coated glass article and a visible light reflectance value of about 8.6% at an interior surface of the coated glass article.

As aspects of certain embodiments, the visible light reflective layer is disposed over at least a portion of the antireflective layer in an area of a heads-up-display (HUD) system.

As aspects of certain embodiments, the first glass sheet and the second glass sheet each have a thickness in a range of about 0.7 mm to 12 mm, preferably about 2.2 mm.

As aspects of certain embodiments, the coated glass article comprises a single glass sheet which may have a thickness about 2.3 mm.

As aspects of certain embodiments, the coated glass article is configured to be used as an automotive window.

As aspects of certain embodiments, the coated glass article is configured to be used a window in building structures.

Note that references herein to a layer or sensor being adjacent a sheet, surface or other layer include references to that layer or sensor provided directly on the sheet, surface or other layer.

Note also that references herein to a layer being disposed over a glass sheet, surface or other layer include references to that layer being provided directly on the sheet, surface or other layer.

In another embodiment, a coated glass article, comprises: a first sheet formed of a glass material having a content of iron oxide (Fe2O3) of about 100 ppm or less; a second sheet formed of a glass material having a content of iron oxide (Fe2O3) of about 100 ppm or less; an adhesive layer interposed between the first and second sheets to join the first sheet to the second sheet; an antireflective layer disposed over one of the first and second sheets, wherein the antireflective layer facilitates a light transmission of at least 80% for at least one infrared wavelength through the coated glass article; and a visible light reflective layer disposed over the antireflective layer, the visible light reflective layer having a refractive index of at least 1.6 and a thickness of no more than 30 nm, wherein the coated glass article exhibits a light transmission of at least 80% for the at least one infrared wavelength and a visible light reflectance of between about 8% and 10%.

As aspects of certain embodiment, the visible light reflective layer is disposed over at least a portion of the antireflective layer in an area of a heads-up-display (HUD) system.

As aspects of certain embodiments, an optical sensor, such as a LIDAR sensor, is disposed adjacent at least one of the antireflective layer and the visible light reflective layer, wherein the optical sensor is configured to emit a light beam having the at least one infrared wavelength.

As aspects of certain embodiments, at least one reflecting layer is disposed adjacent at least a portion of at least one of the first sheet and the second sheet.

As aspects of certain embodiments, the optical sensor is position in alignment with a void formed in the at least one reflecting layer.

In yet another embodiment, a method of producing a coated glass article, comprises: providing a first sheet; disposing an antireflective layer adjacent the first sheet; and disposing a visible light reflective layer on at least a portion of the antireflective layer, the visible light reflective layer having a refractive index of at least 1.6 and a thickness of no more than 30 nm, wherein the coated glass article exhibits a light transmission of at least 80% for at least one wavelength of infrared light and a visible light reflectance of between about 8% and 10%.

Aspects of certain embodiments in the method will be apparent from those described in relation to the coated glass article.

The following detailed description and appended drawings describe and illustrate various exemplary embodiments. The description and drawings serve to enable one skilled in the art to make and use the embodiments, and are not intended to limit the scope of the embodiments in any manner.

FIGS.1-3and5depict glass articles10,10′,10″ each having a laminated construction andFIG.6depicts a glass article10′″ having a monolithic construction. According to the presently disclosed subject matter, each of the glass articles10,10′,10″,10′″ may be planar. However, the glass articles10,10′,10″,10′″ may also be curved such as employed in the case in the automotive industry for rear windows, side windows, sun and moon roofs, and especially windshields as shown inFIG.1.

Preferably, a radius of curvature in at least one direction may be in a range of about 500 mm to about 20,000 mm, and more preferably, in a range of about 1000 mm to about 8,000 mm.

Each of the glass articles10,10′,10″,10′″ may be configured to be used with a heads-up-display (HUD) system8,8′ (shown inFIG.1) and an optical sensor11(shown inFIGS.2and3) in a vehicle (not depicted). It should be appreciated that the HUD system8,8′ may be any HUD system8,8′ as desired. Additionally, each of the glass articles10,10′,10″,10′″ may be configured to be utilized as a window in building structures. It should be appreciated, however, that the glass articles10,10′,10″,10″ may be used in various other applications wherein a certain visible light reflectance and infrared light transmission through the glass articles10,10′,10″,10′″ is desired. It is understood that the glass articles10,10′,10″,10″ may be employed in various industrial, commercial, residential, and automotive applications.

The glass articles10,10′,10″,10′″ of the presently disclosed subject matter may be positioned at a rake angle in a range of about 50° to 70° from vertical and may have a light transmission (when measured with CIE Illuminant A) of at least 75% for two or more wavelengths in a range of about 750 nm to 1 mm, and each of an exterior and interior visible light reflectance may be in a range of about 7.0% to about 10.0%. Preferably, each of the glass articles10,10′,10″,10″ may be positioned at a rake angle of about 60° from vertical, at least a first portion of the glass articles10,10′,10″,10′″ may have a light transmission (when measured with CIE Illuminant A) of at least 94% at a first wavelength of about 905 nm and a second wavelength of about 1550 nm, and at least a second portion of the glass articles10,10′,10″,10″ may have the exterior and interior visible light reflectance substantially the same as that of an uncoated glass article, preferably may be in a range of about 8% to about 9%, and more preferably the exterior visible light reflectance may be at about 8.6% and the interior visible light reflectance may be at about 8.8%.

Referring now toFIG.2, the glass article10depicted is a laminated glazing according to one embodiment of the presently disclosed subject matter. As shown, the glass article10may include a first sheet12and a second sheet14joined to the first sheet12by an adhesive interlayer16. The first and second sheets12,14may be substantially clear and transparent to visible light. Each of the first and second sheets12,14may be produced from a generally low-absorption, high-transmission glass material. In certain embodiments, the first and second sheets12,14may be produced from any glass composition and produced through the use of any glass manufacturing process. Preferably, each of the first and second sheets12,14may be produced from a soda-lime-silica material. The soda-lime-silica material may comprise (by weight), silicon dioxide (SiO2) 70-75%; aluminum oxide (Al2O3) 0-5%; sodium oxide (Na2O) 10-15%; potassium oxide (K2O) 0-5%; magnesium oxide (MgO) 0-10%; calcium oxide (CaO) 5-15%; and sulfur trioxide (SO3) 0-2%. It is understood, however, the first and second sheets12,14each may comprise another composition such as a borosilicate material composition, for example.

In certain embodiments, each of the first and second sheets12,14may be produced from a generally low-iron glass material. Preferably, the first and second sheets12,14may be produced from a glass material having a content of iron oxide (Fe2O3) of about 100 ppm or less. More preferably, the content of iron oxide (Fe2O3) in the first and second sheets12,14may be about 10 ppm or less. Also, transparency and/or absorption characteristics of the first and second sheets12,14may vary between embodiments of the glass article10. For example, the first and second sheets12,14may be tinted. Additionally, a thickness of each of the first and second sheets12,14may vary between embodiments of the glass article10. In certain embodiments, a thickness of each of the first and second sheets12,14may be in a range of about 0.7 mm to about 12 mm. Preferably, each of the first and second sheets12,14may have a thickness of about 2.2 mm.

The first sheet12may have a first major surface1and an opposing second major surface2. The second sheet14may have a first major surface3and an opposing second major surface4. When the glass article10is employed as a windshield in a vehicle, the major surface1faces towards an exterior environment (as indicated by sun17) and the second major surface4faces an interior of the vehicle. As such, the first sheet12is the “outer pane” of the windshield and the second sheet14is the “inner pane” of the windshield.

As illustrated inFIG.2, the adhesive interlayer16may be interposed between the first and second sheets12,14. Similar to the first and second sheets12,14, transparency and/or absorption characteristics of the interlayer16may vary between the embodiments of the glass article10. For example, the adhesive interlayer16may be tinted, if desired. In one embodiment shown inFIG.2, the adhesive interlayer16may be a single-ply disposed adjacent the second major surface2of the first sheet12and the first major surface3of the second sheet14. The single-ply adhesive interlayer16may be formed from a polyvinyl butyral (PVB), an ethylene vinyl acetate (EVA), a polyvinyl chloride (PVC), a polyurethane (PU), an acoustic modified PVB, and/or a liquid curable acrylic resin (e.g. Uvekol®). A thickness of the single-ply adhesive interlayer16may be in a range of about 0.3 mm to about 2.3 mm. Preferably, the single-ply adhesive interlayer16may have a thickness in a range of about 0.3 mm to about 1.1 mm, and more preferably about 0.76 mm. More preferably, the glass sheets12,14of the glass article10may be produced from Pilkington Optiwhite™, commercially available by Pilkington Group Limited, and joined by the single-ply adhesive layer16. In a preferred embodiment, each of the glass sheets12,14may be produced from the Pilkington Optiwhite™ having a thickness of about 2.2 mm and the single-ply interlayer16may have a thickness of about 0.76 mm.

In certain embodiments, the glass article10may further include at least one reflecting layer24. As shown inFIG.2, the at least one reflecting layer24may be disposed adjacent the adhesive interlayer16on either the second major surface2of the first sheet12or the first major surface3of the second sheet14. In certain embodiments, the glass article10may include a plurality of the reflecting layers24disposed adjacent at least one of the first and second sheets12,14. For example, the glass article10may include one of the reflecting layers24disposed adjacent the second major surface2of the first sheet12and another one of the reflecting layers24disposed adjacent the first major surface3of the second sheet14.

The at least one reflecting layer24shown reflects solar and/or infrared radiation. In certain embodiments, the at least one reflecting layer24may be formed of a metal material (e.g. silver), a tin-doped indium oxide, a lanthanum hexaboride, or other such suitable infrared reflecting materials, for example. In certain embodiments, the at least one reflecting layer24may be deposited by sputtering. Various other methods may be used to form the at least one reflecting layer24if desired. Although the at least one reflecting layer24may extend over substantially an entire surface of the first and second sheets12,14, it may be formed to extend over only a portion of the surface thereof. Peripheral edges of the at least one reflecting layer24may be offset from peripheral edges of the first and second sheets12,14and/or the adhesive interlayer16to militate against corrosion and damage. A thickness of the at least one reflecting layer24may be in a range of about 10 nm to about 20 nm. It is understood that the at least one reflecting layer24may have any suitable thickness as desired.

Advantageously, the at least one reflecting layer24may include a void26formed in at least one desired location to militate against potential interference of the at least one reflecting layer24with surrounding components (e.g. the optical sensor11, a camera, a cellular telephone, global positioning systems, road and parking transponders, various other sensors, and the like, etc.). The void26in the at least one reflecting layer24may be formed during a manufacturing of the glass article10(e.g. masking the glass article10at the desired location) or removing a portion of the at least one reflecting layer24by any suitable method such as laser or mechanical deletion or etching, for example. The void26in the at least one reflecting layer24may cover at least one continuous area or be in the form of a desired configuration such as a lined or grid pattern, for example.

As shown, the glass article10may further include a first optical layer or antireflective (AR) layer30. The AR layer30may be configured to enhance light transmission through the glass article10. Preferably, the AR layer30may be formed over the second major surface4of the second sheet14. More preferably, the AR layer30may be formed directly on second major surface4on the second sheet14, essentially with no intervening layers. It is understood, however, that the AR layer30may be formed on other surfaces of the glass article10such as the first major surface1of the first sheet12, for example. As non-limiting examples, the AR layer30may be an additional coating deposited on the second sheet14or an antireflective film disposed thereon. Although the AR layer30may extend over substantially an entire surface of the first and second sheets12,14, it may be formed to extend over only a portion of the surface thereof.

In one embodiment, the AR layer30may be a single-layer coating which comprises silicon dioxide (SiO2) deposited by chemical vapor deposition (CVD). In another embodiment, the AR layer30may be a single-layer coating which comprises titanium oxide (TiO2) nanoparticles deposited by a sol-gel process. It is understood that the AR layer30may be a multi-layer coating formed of any suitable material by any suitable method, as desired.

The AR layer30may be selectively formed at a desired thickness to achieve a desired transmission percentage therethrough. In certain embodiments, the thickness of the AR layer30may be such that to achieve optimal transmission of at least one of the first wavelength and the second wavelength through the glass article10. Preferably, the thickness of the AR layer30may be such to achieve at least an 80% transmission of at least one of the first and second wavelengths through the glass article10. More preferably, the thickness of the AR layer30may be such to achieve at least a 90% transmission of at least one of the first and second wavelengths through the glass article10. Most preferably, the thickness of the AR layer30may be such to achieve at least a 94% transmission of at least one of the first and second wavelengths through the glass article10.

In certain embodiments, the AR layer30may be deposited at a thickness of no less than about 80 nm, and more preferably no less than about 100 nm. In other embodiments, the thickness of the AR layer30may be in a range of about 80 nm to about 400 nm, preferably in a range of about 80 nm to about 160 nm, and more preferably in a range of about 120 nm to about 150 nm.

Preferably, the glass article10may be configured such that the light transmission (when measured with CIE Illuminant A) in a region of the glass article10visible by an occupant of the vehicle may be substantially equivalent to the glass article10without the AR layer30, while the light transmission (when measured with CIE Illuminant A) of at least one of the first and second wavelengths in a region of the glass article10aligned with the optical sensor11may be greater than the glass article10without the AR layer30. Preferably, the light transmission (when measured with CIE Illuminant A) of at least one of the first and second wavelengths in the region of the glass article10aligned with the optical sensor11may be maximized.

In certain embodiments, the glass article10may further include a second optical layer or visible light (VL) reflective layer40. As shown inFIG.2, the VL reflective layer40may be disposed adjacent the AR layer30. In one embodiment, the VL reflective layer40may be disposed over a surface of the AR layer30opposite the second sheet14. The VL reflective layer40shown reflects visible light with having minimal to no effect on infrared light transmission through the glass article10. In one embodiment, the VL reflective layer40may be a coating which comprises tin oxide (SnO2). The VL reflective layer40comprised of tin oxide also enhances a durability of the glass article10. It should be appreciated that the VL reflective layer40may comprise other suitable visible light reflecting materials such as metal oxides having a refractive index greater than 1.6 (e.g. aluminum oxide (Al2O3), titanium dioxide (TiO2), chromium oxide (Cr2O3), and niobium oxide (NbO)).

In certain embodiments, the VL reflective layer40may be deposited by sputtering. Various other methods may be used to form the VL reflective layer40if desired. Although the VL reflective layer40may extend over substantially an entire surface of the AR layer30, it may be formed to extend over only a portion of the surface thereof. In certain embodiments, the VL reflective layer40may be disposed over the AR layer30in an area of the HUD system8to reflect the visible light and allow for proper operation of the HUD system8. A thickness of the VL reflective layer40may be in a range of about 5 nm to about 20 nm, preferably in a range of about 5 nm to about 12 nm, and more preferably in a range of about 6 nm to about 9 nm. It is understood that the VL reflective layer40may have any suitable thickness as desired.

In a preferred embodiment, the VL reflective layer40may comprise a metal oxide having a refractive index of at least 1.6 and less than 1.8 and a thickness of no more than 30 nm. In more preferred embodiments, the VL reflective layer40may comprise a metal oxide having a refractive index of at least 1.8 and a thickness of no more than 20 nm.

In certain embodiments, the optical sensor11may be a light detection and ranging (LIDAR) type of sensor. Such LIDAR sensors include but are not limited to pedestrian detection sensors, pre-crash sensors, closing velocity sensors, and adaptive cruise control sensors, for example. In other embodiments, the optical sensor11may be an optoelectronic system comprised of at least a laser or sensing beam transmitter, at least a receiver including a light or sensing beam collector (telescope or other optics) and at least one photodetector which converts the light or sensing beam into an electrical signal, and an electronic processing chain signal that extracts the information sought.

The optical sensor11may be configured to emit the sensing beam through the glass article10, which strikes a remote object. The sensing beam may be reflected off of the object, caused to pass back through the glass article10, and detected by the receiver of the optical sensor11. Most often, each of the initial sensing beam emitted from the optical sensor11and the reflected sensing beam received by the optical sensor11may have the same wavelength, preferably one of the first and second wavelengths. The at least one photodetector may be configured to convert the sensing beam into the electrical signal which may be then transmitted to a controller or microcontroller (not depicted).

As illustrated, the optical sensor11may be disposed on the second major surface4of the second sheet12. It is understood, however, that the optical sensor11may be positioned at other suitable locations on or adjacent to the glass article10. In certain embodiments, the optical sensor11may be positioned in alignment with the void26formed in the at least one reflecting layer24and at least a portion of the AR layer30to minimize interference and maximize the transmission % of at least one of the wavelengths through the glass article10, which results in improved accuracy and reliability of the optical sensor11.

In one preferred embodiment, the glass article10includes the first sheet12having the at least one reflecting layer24disposed adjacent the second major surface2thereof. The single-ply adhesive layer16may be disposed adjacent the at least one reflecting layer24. More particularly, the at least one reflecting layer24of silver may be deposited onto the adhesive layer16by sputtering. The void26may be formed in the at least one reflecting layer24at the desired location of the void26during the manufacturing of the glass article10. The second sheet14may be disposed adjacent the at least one reflecting layer24. The AR layer30may be then deposited onto the second major surface4of the second sheet14. The VL reflective layer40may be then disposed adjacent the AR layer30. The optical sensor11may be disposed adjacent a surface42of the VL reflective layer40in alignment with the void26formed in the at least one reflecting layer24.

FIG.3shows the glass article10′ similar to that shown inFIG.2and is also a laminated glazing according to another embodiment of the presently disclosed subject matter. Reference numerals for similar structure in respect of the description ofFIG.2is repeated inFIG.3with a prime (′) symbol.

As shown, the glass article10′ may include a first sheet12′ and a second sheet14′ joined to the first sheet12′ by an adhesive interlayer16′. The first and second sheets12′,14′ may be substantially clear and transparent to visible light. Each of the first and second sheets12′,14′ may be produced from a generally low-absorption, high-transmission glass material. In certain embodiments, the first and second sheets12′,14′ may be produced from any glass composition and produced through the use of any glass manufacturing process. Preferably, each of the first and second sheets12′,14′ may be produced from a soda-lime-silica material. The soda-lime-silica material may comprise (by weight), silicon dioxide (SiO2) 70-75%; aluminum oxide (Al2O3) 0-5%; sodium oxide (Na2O) 10-15%; potassium oxide (K2O) 0-5%; magnesium oxide (MgO) 0-10%; calcium oxide (CaO) 5-15%; and sulfur trioxide (SO3) 0-2%. It is understood, however, the first and second sheets12′,14′ each may comprise another composition such as a borosilicate material composition, for example.

In certain embodiments, each of the first and second sheets12′,14′ may be produced from a generally low-iron glass material. Preferably, the first and second sheets12′,14′ may be produced from a glass material having a content of iron oxide (Fe2O3) of about 100 ppm or less. More preferably, the content of iron oxide (Fe2O3) in the first and second sheets12′,14′ may be about 10 ppm or less. Also, transparency and/or absorption characteristics of the first and second sheets12′,14′ may vary between embodiments of the glass article10′. For example, the first and second sheets12′,14′ may be tinted. Additionally, a thickness of each of the first and second sheets12′,14′ may vary between embodiments of the glass article10′. In certain embodiments, a thickness of each of the first and second sheets12′,14′ may be in a range of about 0.7 mm to about 12 mm. Preferably, each of the first and second sheets12′,14′ may have a thickness of about 2.2 mm.

The first sheet12′ may have a first major surface1′ and an opposing second major surface2′. The second sheet14′ may have a first major surface3′ and an opposing second major surface4′. When the glass article10′ is employed as a windshield in a vehicle, the major surface1′ faces towards an exterior environment (as indicated by sun17′) and the second major surface4′ faces an interior of the vehicle. As such, the first sheet12′ is the “outer pane” of the windshield and the second sheet14′ is the “inner pane” of the windshield.

As illustrated inFIG.3, the adhesive interlayer16′ may be interposed between the first and second sheets12′,14′. Similar to the first and second sheets12′,14′, transparency and/or absorption characteristics of the interlayer16′ may vary between the embodiments of the glass article10′. For example, the adhesive interlayer16′ may be tinted, if desired. In the embodiment shown inFIG.3, the adhesive interlayer16′ may be a multi-ply interlayer comprising a first ply18formed of PVB, a second ply20formed of polyethylene terephthalate (PET), and a third ply22formed of PVB. It is understood that each of the plies18,20,22may be formed from other suitable adhesive materials as desired. Each of the plies18,20,22includes respective first surfaces18a,20a,22aand opposing second surfaces18b,20b,22b. As illustrated, the first ply18may be disposed adjacent the second major surface2′ of the first sheet12′ and the first surface20aof the second ply20. The second ply20may be disposed adjacent the second surface18bof the first ply18and the first surface22aof the third ply22. The third ply22may be disposed adjacent the second surface20bof the second ply20and the first major surface3′ of the second sheet14′. A thickness of the first ply18may be in a range of about 0.3 mm to about 2.3 mm, and more preferably about 0.38 mm. The intermediate second ply20has a thickness in a range of about 0.01 mm to 1.0 mm, and more preferably about 0.05 mm. A thickness of the third ply22may be in a range of about 0.3 mm to about 2.3 mm, and more preferably about 0.76 mm. Various other adhesive materials may be used to produce the interlayer16′ as desired. It should be appreciated that the thickness of the adhesive interlayer16′ may vary between embodiments of the glass article10′ according to the presently disclosed subject matter. More preferably, the glass sheets12′,14′ of the glass article10′ may be produced from Pilkington Optiwhite™, commercially available by Pilkington Group Limited, and joined by the multi-ply adhesive layer16′. In a preferred embodiment, each of the glass sheets12′,14′ may be produced from the Pilkington Optiwhite™ having a thickness of about 2.2 mm.

In certain embodiments, the glass article10′ may further include at least one reflecting layer24′. The at least one reflecting layer24′ may be disposed adjacent the adhesive interlayer16′ on either the second major surface2′ of the first sheet12′ or the first major surface3′ of the second sheet14′. Alternatively, as illustrated inFIG.3, the at least one reflecting layer24′ may be incorporated into the multi-ply interlayer16′. In one embodiment, the at least one reflecting layer24′ may be disposed on the second surface18bof the first ply18adjacent the first surface20aof the second ply20. In another embodiment, the at least one reflecting layer24′ may be disposed on the second surface20bof the second ply20adjacent the first surface22aof the third ply22. In certain embodiments, the glass article10′ may include three reflecting layers24′ incorporated into the multi-ply interlayer16′. In certain embodiments, the glass article10′ may include a plurality of the reflecting layers24′ disposed adjacent at least one of the first and second sheets12′,14′ and incorporated into the multi-ply interlayer16′. For example, the glass article10′ may include one of the reflecting layers24′ disposed on the second major surface2′ of the first sheet12′, another one of the reflecting layers24′ disposed on the first major surface3′ of the second sheet14′, and another one of the reflecting layers24′ disposed on at least one of the second surface18bof the first ply18adjacent the first surface20aof the second ply20and the second surface20bof the second ply20adjacent the first surface22aof the third ply22.

The at least one reflecting layer24′ shown reflects solar and/or infrared radiation. In certain embodiments, the at least one reflecting layer24′ may be formed of a metal material (e.g. silver), a tin-doped indium oxide, a lanthanum hexaboride, or other such suitable infrared reflecting materials, for example. In certain embodiments, the at least one reflecting layer24′ may be deposited by sputtering. Various other methods may be used to form the at least one reflecting layer24′ if desired. Although the at least one reflecting layer24′ may extend over substantially an entire surface of the first and second sheets12′,14′ and/or the plies18,20,22, it may be formed to extend over only a portion of the surface thereof. Peripheral edges of the at least one reflecting layer24′ and the second ply20may be offset from peripheral edges of the first and second sheets12′,14′ and/or the plies18,22to militate against corrosion and damage. A thickness of the at least one reflecting layer24′ may be in a range of about 10 nm to about 20 nm. It is understood that the at least one reflecting layer24′ may have any suitable thickness as desired.

Advantageously, the at least one reflecting layer24′ may include a void26′ formed in at least one desired location to militate against potential interference of the at least one reflecting layer24′ with surrounding components (e.g. the optical sensor11′, a camera, a cellular telephone, global positioning systems, road and parking transponders, various other sensors, and the like, etc.). The void26′ in the at least one reflecting layer24′ may be formed during a manufacturing of the glass article10′ (e.g. masking the glass article10′ at the desired location) or removing a portion of the at least one reflecting layer24′ by any suitable method such as laser or mechanical deletion or etching, for example. The void26′ in the at least one reflecting layer24′ may cover at least one continuous area or be in the form of a desired configuration such as a lined or grid pattern, for example.

As shown, the glass article10′ may further include a first optical layer or antireflective (AR) layer30′. The AR layer30′ may be configured to enhance light transmission through the glass article10′. Preferably, the AR layer30′ may be formed over the second major surface4′ of the second sheet14′. More preferably, the AR layer30′ may be formed directly on second major surface4′ on the second sheet14′, essentially with no intervening layers. It is understood, however, that the AR layer30′ may be formed on other surfaces of the glass article10′ such as the first major surface1′ of the first sheet12′, for example. As non-limiting examples, the AR layer30′ may be an additional coating deposited on the second sheet14′ or an antireflective film disposed thereon. Although the AR layer30′ may extend over substantially an entire surface of the first and second sheets12′,14′, it may be formed to extend over only a portion of the surface thereof.

In one embodiment, the AR layer30′ may be a single-layer coating which comprises silicon dioxide (SiO2) deposited by chemical vapor deposition (CVD). In another embodiment, the AR layer30′ may be a single-layer coating which comprises titanium oxide (TiO2) nanoparticles deposited by a sol-gel process. It is understood that the AR layer30′ may be a multi-layer coating formed of any suitable material by any suitable method, as desired.

The AR layer30′ may be selectively formed at a desired thickness to achieve a desired transmission percentage therethrough. In certain embodiments, the thickness of the AR layer30′ may be such that to achieve optimal transmission of at least one of the first wavelength and the second wavelength through the glass article10′. Preferably, the thickness of the AR layer30′ may be such to achieve at least an 80% transmission of at least one of the first and second wavelengths through the glass article10′. More preferably, the thickness of the AR layer30′ may be such to achieve at least a 90% transmission of at least one of the first and second wavelengths through the glass article10′. Most preferably, the thickness of the AR layer30′ may be such to achieve at least a 94% transmission of at least one of the first and second wavelengths through the glass article10′.

In certain embodiments, the AR layer30′ may be deposited at a thickness of no less than about 80 nm, and more preferably no less than about 100 nm. In other embodiments, the thickness of the AR layer30′ may be in a range of about 80 nm to about 400 nm, preferably in a range of about 80 nm to about 160 nm, and more preferably in a range of about 120 nm to about 150 nm.

Preferably, the glass article10′ may be configured such that the light transmission (when measured with CIE Illuminant A) in a region of the glass article10′ visible by an occupant of the vehicle may be substantially equivalent to the glass article10′ without the AR layer30′, while the light transmission (when measured with CIE Illuminant A) of at least one of the first and second wavelengths in a region of the glass article10′ aligned with the optical sensor11′ may be greater than the glass article10′ without the AR layer30′. Preferably, the light transmission (when measured with CIE Illuminant A) of at least one of the first and second wavelengths in the region of the glass article10′ aligned with the optical sensor11′ may be maximized.

In certain embodiments, the glass article10′ may further include a second optical layer or visible light (VL) reflective layer40′. As shown inFIG.3, the VL reflective layer40′ may be disposed adjacent the AR layer30′. In one embodiment, the VL reflective layer40′ may be disposed over a surface of the AR layer30′ opposite the second sheet14′. The VL reflective layer40′ shown reflects visible light with having minimal to no effect on infrared light transmission through the glass article10′. In one embodiment, the VL reflective layer40′ may be a coating which comprises tin oxide (SnO2). The VL reflective layer40′ comprised of tin oxide also enhances a durability of the glass article10′. It should be appreciated that the VL reflective layer40′ may comprise other suitable visible light reflecting materials such as metal oxides having a refractive index greater than 1.6 (e.g. aluminum oxide (Al2O3), titanium dioxide (TiO2), chromium oxide (Cr2O3), and niobium oxide (NbO)).

In certain embodiments, the VL reflective layer40′ may be deposited by sputtering. Various other methods may be used to form the VL reflective layer40′ if desired. Although the VL reflective layer40′ may extend over substantially an entire surface of the AR layer30′, it may be formed to extend over only a portion of the surface thereof. In certain embodiments, the VL reflective layer40′ may be disposed over the AR layer30′ in an area of the HUD system8′ to reflect the visible light and allow for proper operation of the HUD system8′. A thickness of the VL reflective layer40′ may be in a range of about 5 nm to about 20 nm, preferably in a range of about 5 nm to about 12 nm, and more preferably in a range of about 6 nm to about 9 nm. It is understood that the VL reflective layer40′ may have any suitable thickness as desired.

In a preferred embodiment, the VL reflective layer40′ may comprise a metal oxide having a refractive index of at least 1.6 and less than 1.8 and a thickness of no more than 30 nm. In more preferred embodiments, the VL reflective layer40′ may comprise a metal oxide having a refractive index of at least 1.8 and a thickness of no more than 20 nm.

In certain embodiments, the optical sensor11′ may be a light detection and ranging (LIDAR) type of sensor. Such LIDAR sensors include but are not limited to pedestrian detection sensors, pre-crash sensors, closing velocity sensors, and adaptive cruise control sensors, for example. In other embodiments, the optical sensor11′ may be an optoelectronic system comprised of at least a laser or sensing beam transmitter, at least a receiver including a light or sensing beam collector (telescope or other optics) and at least a photodetector which converts the light or sensing beam into an electrical signal, and an electronic processing chain signal that extracts the information sought.

The optical sensor11′ may be configured to emit the sensing beam through the glass article10′, which strikes a remote object. The sensing beam may be reflected off of the object, caused to pass back through the glass article10′, and detected by the receiver of the optical sensor11′. Most often, each of the initial sensing beam emitted from the optical sensor11′ and the reflected sensing beam received by the optical sensor11′ may have the same wavelength, preferably one of the first and second wavelengths. The at least one photodetector may be configured to convert the sensing beam into the electrical signal which may be then transmitted to a controller or microcontroller (not depicted).

As illustrated, the optical sensor11′ may be disposed on the second major surface4′ of the second sheet12′. It is understood, however, that the optical sensor11′ may be positioned at other suitable locations on or adjacent to the glass article10′. In certain embodiments, the optical sensor11′ may be positioned in alignment with the void26′ formed in the at least one reflecting layer24′ and at least a portion of the AR layer30′ to minimize interference and maximize the transmission % of at least one of the wavelengths through the glass article10′, which results in improved accuracy and reliability of the optical sensor11′.

In one preferred embodiment, the glass article10‘ includes the first sheet12’ having the first ply18of the multi-ply adhesive layer16′ disposed adjacent the second major surface2′ thereof. The at least one reflecting layer24′ may be disposed adjacent the second surface18bof the first ply18. The second ply20′ may be disposed adjacent the at least one reflecting layer24′. More particularly, the at least one reflecting layer24′ of silver may be deposited on the first surface20aof the second ply20by sputtering. The void26′ may be formed in the at least one reflecting layer24′ at the desired location of the void26′ during the manufacturing of the glass article10′. The third ply22may be then disposed adjacent the second surface20bof the second ply20. The second sheet14′ may be disposed adjacent the second surface22bof the third ply22. The AR layer30′ may be then deposited onto the second major surface4′ of the second sheet14′. The VL reflective layer40′ may be then disposed adjacent the AR layer30′. The optical sensor11′ may be disposed adjacent a surface42′ of the VL reflective layer40′ in alignment with the void26′ formed in the at least one reflecting layer24′.

As detailed inFIG.4, when the glass article10is an uncoated laminated glazing (e.g. without the AR layer30and the VL reflective layer40), the glass article10exhibits a visible light reflectance value of about 8.7% at an exterior surface (R-1) of the glass article10, a visible light reflectance value of about 8.7% at an interior surface (R-4) of the glass article10, about a 88.4% light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm) when positioned substantially vertical, and about a 81% light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm) when positioned at a rake angle of about 60° from vertical.

When the glass article10is a laminated glazing including the AR layer30comprising of 130 nm silicon dioxide (SiO2), the glass article10exhibits a visible light reflectance value of about 7.2% at an exterior surface (R-1) of the glass article10, a visible light reflectance value of about 7.2% at an interior surface (R-4) of the glass article10, about a 90.5% transmission at the first wavelength (e.g. 905 nm) when positioned substantially vertical, and about a 82.4% transmission at the first wavelength (e.g. 905 nm) when positioned at a rake angle of about 60° from vertical.

When the glass article10is a laminated glazing including the AR layer30comprising of 130 nm silicon dioxide (SiO2) and the VL reflective layer40comprising of 8 nm of tin oxide (SnO2), the glass article10exhibits a visible light reflectance value of about 8.6 at an exterior surface (R-1) of the glass article10, a visible light reflectance value of about 8.6% at an interior surface (R-4) of the glass article10, about a 90.5% transmission at the first wavelength (e.g. 905 nm) when positioned substantially vertical, and about a 82.5% transmission at the first wavelength (e.g. 905 nm) when positioned at a rake angle of about 60° from vertical.

Referring now toFIG.5, the glass article10″ is a laminated glazing shown according to another embodiment of the presently disclosed subject matter. The glass article10″ is similar to that shown inFIGS.2and3. Reference numerals for similar structure in respect of the description ofFIGS.2and3is repeated inFIG.5with a double prime (″) symbol. The glass article10″ illustrated inFIG.5may be suitable for building applications. The glass article10″ includes the first sheet12″, the adhesive layer16″ disposed adjacent the first sheet12″, and the second sheet14″ disposed adjacent the adhesive layer16″. The AR layer30″ may be then deposited onto the second major surface4″ of the second sheet14″. The VL reflective layer40″ may be then disposed adjacent the AR layer30″.

FIG.6illustrates the glass article10″ according to another embodiment of the presently disclosed subject matter. The glass article10″ is similar to that shown inFIGS.2,3, and5. However, the glass article10″ is monolithic. Reference numerals for similar structure in respect of the description ofFIGS.2,3, and5is repeated inFIG.6with a triple prime (″) symbol. The glass article10″′ may also be suitable for building applications. The glass article10′″ may include a single glass sheet12′″. In certain embodiments, the glass sheet12′″ may have a thickness of about 2.3 mm. The AR layer30′″ may be then deposited onto the second major surface2″ of the glass sheet12′″. The VL reflective layer40″ may be then disposed adjacent the AR layer30′″.

Referring now toFIG.7, the table provides various characteristics of an uncoated monolithic glass article, a monolithic glass article coated with the AR layer30′″ of silicon dioxide (SiO2), a monolithic glass article coated with the AR layer30″ of silicon dioxide (SiO2) having a thickness of about 146 nm, the monolithic glass article10″ coated with the AR layer30′″ of silicon dioxide (SiO2) having a thickness of about 146 nm and the VL reflective layer40′″ of tin oxide (SnO2) having a thickness of about 10 nm, and the monolithic glass article10″ coated with the AR layer30′″ of silicon dioxide (SiO2) having a thickness of about 146 nm and the VL reflective layer40″ of tin oxide (SnO2) having a thickness of about 12 nm. As shown, the uncoated monolithic glass article (e.g. without the AR layer30′″ and the VL reflective layer40′″) exhibits about a 92.3% visible light transmission (when measured with CIE Illuminant A), about a 0.06 haze value, a visible light reflectance value of about 8.8%, coordinates a* of about −0.12 and b* of about −0.93 (which define color in accordance with CIELAB color scale system), and about a 90.5% infrared light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm). The coated monolithic glass article including only the AR layer30′″ exhibits about a 93.2% visible light transmission (when measured with CIE Illuminant A), about a 0.06 haze value, a visible light reflectance value of about 7.8%, coordinates a* of about −0.44 and b* of about −3.2 (which define color in accordance with CIELAB color scale system), and about a 92.0% infrared light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm). The coated monolithic glass article10′″ including the AR layer30′″ and the VL reflective layer40′″ exhibits about a 92.4% visible light transmission (when measured with CIE Illuminant A), about a 0.07 haze value, a visible light reflectance value of about 8.45%, coordinates a* of about −0.8 and b* of about −3.5 (which define color in accordance with CIELAB color scale system), and about a 92.0% infrared light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm). The coated monolithic glass article10′″ including the AR layer30′″ and the VL reflective layer40′″ exhibits about a 92.4% visible light transmission (when measured with CIE Illuminant A), about a 0.07 haze value, a visible light reflectance value of about 8.65%, coordinates a* of about −0.85 and b* of about −3.6 (which define color in accordance with CIELAB color scale system), and about a 92.1% infrared light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm). Notably, the coated monolithic glass article10′″ including the AR layer30′″ and the VL reflective layer40′″ has a visible light reflectance value comparable to the uncoated monolithic glass article, which provides sufficient visible light reflection for proper operation of the HUD system8, as well as a 92.0% infrared light transmission (when measured with CIE Illuminant A) at the first wavelength (e.g. 905 nm), which is sufficient for proper operation of the optical sensor11.

From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of the subject matter of the embodiments described herein and, without departing from the spirit and scope thereof, can make various changes and modifications to the embodiments to adapt them to various usages and conditions.