Glazing inspection

Abstract

This disclosure describes a method for inspecting a glazing. The glazing is configured to be mounted on a vehicle having a head-up display projector having a first projection distance from an eyebox position. The inspection method includes the steps of: positioning the glazing relative to a light source; irradiating a portion of a first head-up display area with light from the light source to generate a first virtual image on a first image plane, wherein the first image plane is a first distance from the eyebox position; capturing a first image by imaging the first virtual image on the first image plane with an imaging system; and determining a first performance parameter of the glazing using the first image, wherein the first distance is different from the first projection distance. Apparatus for carrying out the method is also described.

Description

Technical Field

[0001] The present invention relates to an inspection method for a glazing having at least one head-up display area and an inspection apparatus for a glazing having at least one head-up display area.

Background Art

[0002] A head-up display (HUD) system for vehicles is widely known. Such a HUD system typically includes a head-up display projector in the vehicle for projecting light onto the vehicle's windshield, and a virtual image is generated on the line of sight of the vehicle driver when viewed through the windshield by the light reflected from the windshield. Therefore, the virtual image appears behind the windshield and in front of the vehicle driver when viewed from the position of the glove box inside the vehicle, and the glove box position represents the position of the vehicle driver's eyes.

[0003] As a vehicle windshield used in a head-up display system, one in which a virtual image appears at a projection distance of about 1 m to 3 m or less (i.e., about 2 m) from the glove box position is known. Such a head-up display system can be used to display basic information regarding vehicle states such as the speed of the vehicle in simple alphanumeric characters. In this field, such a head-up display system is often referred to as a "conventional head-up display system" or a "conventional HUD".

[0004] In recent years, head-up systems have been developed that project more detailed information to the driver in the form of "augmented reality," in which case the information can be superimposed on the real world's field of view. Typically, this type of augmented reality (or AR) head-up display has a larger projection area on the windscreen than the conventional HUD systems mentioned above. Furthermore, the image appears far behind the windscreen from the driver's perspective, often with a projection distance of about 10m from the eyebox position (compared to 1m-2m for conventional HUDs).

[0005] A vehicle equipped with a HUD system having an inclined or tilted image plane is described in International Patent Publication 2017 / 195026. In such a system, different portions of a path (i.e., a driving route) can be displayed on the inclined or tilted image plane. For example, a first portion of the path may be projected at a first focal length, a second portion of the path may be projected at a second focal length greater than the first, and a third portion of the path may be projected at a third distance greater than the second focal length. The focal length associated with the graphical overlay of the path may change continuously between the first to the third portion, providing a smooth continuity or gradient equivalent to the focal lengths of real-world objects associated with the path.

[0006] A similar system is described in International Patent Publication 2019 / 131296, see, for example, Figure 1 and related description. The HUD device is mounted on a vehicle and projects display light onto the windshield, thereby displaying an image as a virtual image on a virtual screen set up in front of the windshield. The HUD device comprises a display unit that emits display light and a control unit that controls the image displayed on the virtual surface by controlling the operation of the display unit. The virtual surface is set to be inclined forward with respect to the vertical direction of the vehicle.

[0007] To evaluate the performance of a windscreen used in a vehicle's head-up display system, inspections are typically performed before the windscreen is installed in the vehicle. Generally, light in the form of a matrix pattern is projected onto the windscreen, and the image at the eyebox position (or multiple eye positions within the eyebox) is compared to predetermined acceptable head-up display performance parameters. Parameters such as ghosting, rotation, linear distortion, magnification, and aspect ratio may be determined.

[0008] In head-up display systems where the virtual image is located 1 to 2 meters from the eyebox, the optical configuration required for inspection and measurement is relatively simple because the virtual image is small and has low curvature. However, in head-up display systems where the virtual image is located much further away from the eyebox (i.e., approximately 5 to 10 meters or more in the case of AR HUDs), other factors such as image size and windscreen curvature become more pronounced as the distance increases. Adjusting the angle of the optical elements of the inspection system also becomes more important as the distance to the virtual image increases.

[0009] U.S. Patent No. 11,340,453 discusses how, in augmented reality HUD systems, the significant increase in image size and curvature can cause parts of the image to always appear out of focus due to the limitations of the depth of field of the camera unit used during inspection. The issue of astigmatism is also mentioned. [Overview of the Initiative]

[0010] The present invention aims to provide at least an alternative method for inspecting a vehicle windscreen having a head-up display area, particularly a head-up display area for an augmented reality head-up display system.

[0011] Therefore, according to a first aspect of the present invention, a method for inspecting a glazing is provided. The glazing is configured to be mounted on a vehicle having a head-up display projector, and as a result, when in use, light from the head-up display projector illuminates a first head-up display area of ​​the glazing, generating a first virtual image at a first projection distance from the eyebox position, and the method for inspecting the glazing is, (i) A step of positioning the glazing relative to the light source, (ii) A step of irradiating light from a light source toward at least a portion of a first head-up display area of ​​glazing to generate a first virtual image on a first image plane, wherein the first image plane is at a first distance from the eyebox position, (iii) The step of capturing a first image by capturing a first virtual image in the first image plane with an imaging system, (iv) The step of determining at least first performance parameters of a first head-up display area of ​​glazing using a first image of a first virtual image in a first image plane, wherein the first distance is different from the first projection distance.

[0012] By measuring the virtual image in a first image plane at a first distance from the eyebox position, the inventors have found that the performance of the glazing at the first projection distance can be accurately evaluated, even when the first distance is different from the first projection distance of the first head-up display area when the glazing is installed in the vehicle.

[0013] In step (ii), when a portion of the first head-up display area is illuminated, the first virtual image is generated on a first image plane at a first distance from the eyebox position, but not at a first projection distance from the eyebox position. This makes it possible to perform inspection measurements only on the first image plane, and to determine performance parameters for different areas of the windscreen that may become head-up display areas with different projection distances when mounted on a vehicle. The performance parameters measured at the first distance are not necessarily identical to the performance parameters measured at the first projection distance, but the inventors have surprisingly found a good correlation between the performance parameters measured at the first distance and the performance parameters measured at the first projection distance.

[0014] Preferably, the first performance parameter determined in (iv) is compared to a suitable performance specification. The suitable performance specification is preferably a range of the first performance parameter at a first distance. For example, if the performance parameter value in (iv) is determined to be P1, the performance specification may specify that P1 can vary in the range of P1-Δp1 to P1+Δp2. Such a performance specification may differ for glazing intended for different vehicles.

[0015] Preferably, the first performance parameters of the glazing first head-up display area relate to ghosting, distortion, magnification, aspect ratio, or displacement.

[0016] Preferably, the first projection distance exceeds 3m, more preferably exceeds 5m, and even more preferably exceeds 7m.

[0017] Preferably, the first projection distance is less than 150m, more preferably less than 50m, even more preferably less than 20m, and even more preferably less than 15m.

[0018] Preferably, the first distance is about 4m or less.

[0019] Preferably, the first distance is about 3 m or less.

[0020] Preferably, the first distance is about 2.5 m or less.

[0021] Preferably, the first distance exceeds about 0.5 m, and more preferably exceeds about 1 m.

[0022] Preferably, on the condition that the first distance is shorter than the first projection distance, the first projection distance is 7 m to 150 m, and the first distance is 1 m to 30 m.

[0023] Preferably, the first projection distance is 7 m to 15 m, and the first distance is 1 m to 3 m.

[0024] Preferably, the first head-up display area is for an extended reality head-up display system.

[0025] Preferably, the first head-up display area is at least about 5% of the area of the glazing.

[0026] Preferably, the first head-up display area is less than about 50% of the area of the glazing, and more preferably less than about 25%.

[0027] Preferably, the glazing is a windshield.

[0028] Preferably, the glazing is a windshield for an automobile, a train, an aircraft or a water vehicle.

[0029] Preferably, the glazing comprises a first glazing material sheet joined to a second glazing material sheet by an intermediate layer structure comprising at least one sheet of adhesive intermediate layer material, the second glazing material sheet being the outer sheet facing the external environment side when the glazing is attached to the vehicle, and the inner sheet having a major surface facing the interior of the vehicle when the glazing is attached to the vehicle, and the outer sheet having an outer surface facing the external environment side of the vehicle to which the glazing is attached.

[0030] Preferably, the imaging system comprises at least one camera.

[0031] Preferably, the imaging system comprises at least one fixed camera for capturing an image of a first virtual image from each fixed eye position within the eye box.

[0032] Preferably, the imaging system comprises at least one movable camera for capturing an image of a first virtual image from a first eye position within the eye box, the movable camera being movable to a second eye position within the eye box and capturing different images of the first virtual image.

[0033] Preferably, the first image of the first virtual image is captured by a camera located at the eye box position.

[0034] Preferably, the first image of the first virtual image is captured by a camera located at the first eye position within the eye box. [[ID=​​​​​​​​​​​​​Preferably, the first virtual image at a first distance is configured to be parallel to the first virtual image at a first projection distance of the head-up display system.

[0039] Preferably, the first virtual image at the first distance is configured to be parallel to the eyebox position.

[0040] In some embodiments, the first virtual image at a first projection distance is part of an inclined virtual image, which is inclined with respect to the eyebox position. A vehicle having such a HUD system is described in International Patent Publication 2019 / 131296, in which the virtual image is displayed on a virtual plane set to be inclined forward with respect to the vertical direction of the vehicle.

[0041] In some embodiments, the first distance is shorter than the first projection distance.

[0042] Preferably, the first projection distance is greater than xm, and x = 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100.

[0043] Preferably, the first projection distance is less than ym, and y = 110, 100, 90, 80, 70, 60, 50, 40, 30.

[0044] Preferably, the first projection distance is 5m to 15m.

[0045] Preferably, the first distance is less than or equal to jm, and j = 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5.

[0046] Preferably, the first distance is at least km, and k = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.

[0047] Preferably, the first distance is 0.5m to 5m, more preferably 0.5m to 4m, and even more preferably 0.5m to 3m.

[0048] In some embodiments, the first distance is longer than the first projection distance.

[0049] Preferably, the first distance is greater than x'm, and x' = 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100.

[0050] Preferably, the first distance is less than y'm, and y' = 110, 100, 90, 80, 70, 60, 50, 40, 30.

[0051] Preferably, the first distance is 5m to 15m.

[0052] Preferably, the first projection distance is less than or equal to j'm, and j' = 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.5.

[0053] Preferably, the first projection distance is at least k'm, where k' = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.

[0054] Preferably, the first projection distance is 0.5m to 5m, more preferably 0.5m to 4m, and even more preferably 0.5m to 3m.

[0055] In some embodiments, the first projection distance exceeds 20 m.

[0056] Preferably, the first projection distance is greater than x''m, and x'' = 30, 40, 50, 60, 70, 80, 90, 100.

[0057] Preferably, the first projection distance is less than y''m, and y'' = 110, 100, 90, 80, 70, 60, 50, 40, 30.

[0058] In some embodiments, the first image of the first virtual image is captured by an imaging system located at the eyebox position.

[0059] Preferably, the first image of the first virtual image is captured by a camera located at the eyebox position.

[0060] Preferably, the first image of the first virtual image is captured by a camera located at the first eye position within the eye box.

[0061] In some embodiments, the first image of the first virtual image is captured at a first eye position within the eye box.

[0062] Preferably, the method includes the steps of capturing a second image of the first virtual image in the first image plane at a second eye position in the eye box, and determining a first performance coefficient using the second image of the first virtual image.

[0063] In some embodiments, multiple images of the first virtual image are captured, each image being captured at a different eye position within the eyebox.

[0064] Preferably, each image in a plurality of images is used to determine the corresponding first performance parameter.

[0065] Preferably, each image is used to construct a first virtual image, and the constructed first virtual image is used to determine a first performance parameter.

[0066] In some embodiments, the glazing comprises a first glazing material plate joined to a second glazing material plate by an intermediate layer structure comprising at least one sheet of adhesive intermediate layer material, wherein the second glazing material plate is an inner sheet facing the interior of the vehicle when the glazing is mounted on the vehicle, the inner sheet having an inner surface facing the interior of the vehicle when the glazing is mounted on the vehicle, and the resulting first virtual image comprises reflected light from at least the inner surface of the inner sheet.

[0067] In these embodiments, the first glazing material plate is an outer sheet facing the external environment of the vehicle to which the glazing is attached, and the outer sheet has an outer surface facing the external environment of the vehicle to which the glazing is attached.

[0068] Preferably, the first virtual image produced comprises reflected light from at least the intermediate layer structure.

[0069] Preferably, the first virtual image produced in these embodiments comprises at least reflected light from the outer surface. Reflections of light from the inner and outer surfaces may be used to determine performance parameters related to ghosting.

[0070] In some embodiments, the imaging system includes a first camera positioned at a first eye position within the eyebox to capture a first image of a first virtual image, and a second camera positioned at a second eye position within the eyebox to capture a second image of the first virtual image.

[0071] In some embodiments, the imaging system is movable relative to the glazing, capturing a first image at a first position relative to the glazing and a second image at a second position relative to the glazing. The imaging system may be movable using a robotic arm or the like.

[0072] When the imaging system is in a first position relative to the glazing, preferably the first image is captured at a first eye position within the eye box.

[0073] If the imaging system is movable and moved to a second position relative to glazing, preferably the second image is captured at the second position within the eyebox.

[0074] In embodiments where the imaging system is movable relative to glazing, it is preferable to capture multiple images to construct an image of the entire first virtual image.

[0075] In some embodiments, the light from the light source is in the form of a pattern, preferably comprising at least one dot and / or at least one line.

[0076] Preferably, the pattern is a dedicated pattern for inspecting glazing for a specific vehicle model.

[0077] In some embodiments, light from a light source is in the form of a pattern, a first virtual image of the pattern in a first image plane is distorted by glazing, and the first virtual image distorted by glazing is compared to a reference image or reference pattern of the pattern when determining the performance parameters of the glazing.

[0078] As is known to those skilled in the art, a reference image or reference pattern is an undistorted image and may be distorted in order to be projected onto the glazing under inspection.

[0079] In some embodiments, the first performance parameter of the first head-up display area of ​​glazing is determined using only the first image of the first virtual image.

[0080] In such embodiments, the first image of the first virtual image is preferably captured by an imaging system located at a first eye position within the eyebox.

[0081] In some embodiments, in (ii), light from the light source illuminates at least the entire first head-up display area.

[0082] Preferably, in (iii), the entire first virtual image from the fully illuminated first head-up display area is imaged, and the captured first image is an image of the entire first virtual image.

[0083] Preferably, only a portion of the entire first virtual image from the fully illuminated first head-up display area is captured as the first image in (iii).

[0084] Preferably, the image of the entire first virtual image from the first head-up display area is composed of a plurality of images, each of which is an image of a different portion of the entire first virtual image from the first head-up display area. The plurality of images may be acquired at different eye positions in the eye box using an imaging system which preferably includes at least one camera that may be fixed or movable.

[0085] In some embodiments, the performance of the entire first head-up display area is determined by performing steps (ii) and (iii) multiple times to illuminate multiple different portions of the first head-up display area of ​​glazing.

[0086] Preferably, each portion of the first head-up display area is illuminated individually.

[0087] Preferably, each different part is used to determine the corresponding first performance parameter.

[0088] Preferably, each corresponding first image from different illuminated portions of the first head-up display area is used to construct an image of the entire first virtual image from the first head-up display area. The image of the entire first virtual image from the first head-up display area thus constructed may be used to determine a first performance parameter of the glazing first head-up display area.

[0089] In some embodiments, the glazing is configured to be mounted on a vehicle so that, when in use, light from the head-up display projector illuminates a second head-up display area of ​​the glazing, generating a virtual image at a second projection distance from the eyebox position, where the second projection distance is shorter than the first projection distance.

[0090] Preferably, the glazing inspection method includes the step of inspecting a second head-up display area to determine at least a first performance parameter of the second head-up display area of ​​the glazing.

[0091] Preferably, the inspection method for a second head-up display area includes the steps of: irradiating at least a portion of the second head-up display area of ​​glazing with light from a light source or other light source to generate a second virtual image on a second image plane, wherein the second image plane is at a second distance from the eyebox position; capturing a first image of the second virtual image on the second image plane using an imaging system; and determining at least first performance parameters of the second head-up display area of ​​glazing using the first image of the second virtual image.

[0092] Preferably, the first performance parameter of the second head-up display area of ​​the glazing is compared to an appropriate performance specification.

[0093] Preferably, the second distance from the eyebox position in the second image plane is the same as the first distance from the eyebox position in the first image plane.

[0094] Preferably, the second distance is the same as the second projection distance.

[0095] Preferably, the first projection distance is 5m to 20m, and the second projection distance is 1m to 5m.

[0096] Preferably, the first head-up display area of ​​the glazing has a first area, and the second head-up display area of ​​the glazing has a second area, with the first area being larger than the second area.

[0097] Preferably, the first area is at least 1.5 times the second area, more preferably 2 times, and even more preferably 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times, or 10 times.

[0098] Preferably, the first area is less than 20 times the second area.

[0099] Preferably, the first region is for an augmented reality head-up display system, and the second region is for a conventional head-up display system.

[0100] In some embodiments, the method is configured to be mounted in a vehicle, and as a result, when in use, light from a head-up display projector illuminates a second head-up display area of ​​the glazing, generating a second virtual image at a second projection distance from the eyebox position, the second projection distance being longer than the first projection distance, and is used to inspect the glazing.

[0101] Preferably, the glazing inspection method includes inspecting a second head-up display area to determine at least a first performance parameter of the second head-up display area of ​​the glazing.

[0102] Preferably, the inspection method for a second head-up display area includes the steps of: irradiating at least a portion of the second head-up display area of ​​glazing with light from a light source or other light source to generate a second virtual image on a second image plane, wherein the second image plane is at a second distance from the eyebox position; capturing a first image of the second virtual image on the second image plane using an imaging system; and determining at least first performance parameters of the second head-up display area of ​​glazing using the first image of the second virtual image.

[0103] Preferably, the first performance parameter of the second head-up display area of ​​the glazing is compared to an appropriate performance specification.

[0104] Preferably, the second distance from the eyebox position in the second image plane is the same as the first distance from the eyebox position in the first image plane. This allows the measurement of the first parameters of the first and second head-up display areas of glazing to be performed with the same optical arrangement, which has the advantage of speeding up the inspection procedure.

[0105] Preferably, the first distance is the same as the second projection distance.

[0106] In some embodiments, the method includes a calibration step, in which (iv) a first performance parameter measured in a first image plane can be converted to a corresponding first performance parameter at a first projection distance or other projection distances from the eyebox position using at least a first correction factor determined in the calibration step.

[0107] Preferably, the first correction factor is determined using ray tracing or by measuring a first performance parameter of a reference virtual image generated at a first image plane and a first projection distance or other distance.

[0108] By determining appropriate correction factors between first performance parameters at different distances from the eyebox position, such as the first distance and the first projection distance, it becomes possible to measure the performance parameters in the first image plane at the first distance from the eyebox position and calculate the performance parameters at the first projection distance. This may be useful when the actual performance parameters at the first projection distance are required.

[0109] Preferably, the first correction coefficient includes a coefficient for transforming at least one of ghosting, distortion, magnification, aspect ratio, and displacement.

[0110] In some embodiments, the head-up display projector includes at least a first projector for illuminating a first head-up display area of ​​glazing.

[0111] In some embodiments, when the glazing is installed in the vehicle, the eye box may be in a standard position and may be adjustable to a higher or lower position depending on the height of the vehicle's driver.

[0112] In embodiments where the glazing has a first head-up display area and a second head-up display area, the head-up display projector preferably comprises a first projector for illuminating the first head-up display area of ​​the glazing and a second projector for illuminating the second head-up display area of ​​the glazing.

[0113] Preferably, the first projector and the second projector are mounted in the same housing.

[0114] The present invention also provides, in a second aspect, an inspection apparatus for a glazing, the glazing being configured to be mounted on a vehicle having a head-up display projector, so that when in use, light from the head-up display projector illuminates a first head-up display area of ​​the glazing, generating a first virtual image at a first projection distance from the eyebox position. The apparatus comprises a fixture, a light source, an imaging system, and a computer, the fixture being positioned relative to the light source and configured to hold a windscreen during inspection measurement, so that light from the light source strikes the glazing, generating a virtual image in a first image plane, the first image plane being at a first distance from the eyebox position, the imaging system being positioned relative to the glazing during the inspection step and capturing an image of the virtual image in the first image plane through the glazing, and the computer having a program for analyzing the captured image of the virtual image in the first image plane to determine at least first performance parameters of the glazing, the first image plane being at a position different from the first projection distance.

[0115] Preferably, the imaging system is located at the eyebox position.

[0116] Embodiments of the present invention will be described below illustratively with reference to the attached drawings (which are not shown in scale). [Brief explanation of the drawing]

[0117] [Figure 1] A schematic plan view of a vehicle windscreen with a single head-up display area is shown. [Figure 2] Figure 1 shows a schematic side view of the vehicle windscreen when it is installed on a vehicle. [Figure 3] A schematic side view of an apparatus for carrying out the method according to the first aspect of the present invention is shown. [Figure 4] This shows a comparison of the measured heights of virtual image elements in the first image plane and in a second image plane different from the first image plane. [Figure 5]This shows a comparison between the area of ​​the light-illuminated windscreen and the area of ​​the first head-up display. [Figure 6] The first head-up display area is illuminated by a light source, revealing six captured image regions that constitute the overall virtual image. [Modes for carrying out the invention]

[0118] Figure 1 shows a plan view of a vehicle windscreen 1 equipped with a first head-up display area 3. In this example, the first head-up display area is for a vehicle augmented reality head-up display system, and a virtual image is generated approximately 10 m behind the windscreen from the driver's viewpoint.

[0119] In this example, the first head-up display area 3 is shown as a rectangle, but other shapes are also possible, such as the outer perimeter of a trapezoid.

[0120] Figure 2 shows a schematic side view of the windscreen 1 when mounted vertically to a vehicle (not shown) at a mounting angle 7. When in use, a suitable head-up display projector 9, which may include multiple projector systems, illuminates the first head-up display area 3. When viewed through the windscreen 1 at the eyebox position 11, the driver sees a first virtual image 15 at a first projection distance 19 from the eyebox position 11. The first virtual image 15 at the first projection distance 19 from the eyebox position 11 may be called the first virtual image in use or the first virtual image in the vehicle.

[0121] As is known to those skilled in the art, the eyebox position may be adjustable upward or downward from a standard position to accommodate drivers of different heights, thereby ensuring that the driver's eyes are positioned within the eyebox.

[0122] In the case of an augmented reality head-up display system, the first projection distance 19 is typically more than about 5m, typically about 5m to 20m, or about 7m to 15m, or about 8m to 12m, i.e., about 10m.

[0123] The windscreen 1 is typically made from two glass sheets laminated with an intermediate layer structure comprising at least one sheet of adhesive intermediate layer material, such as polyvinyl butyral (PVB). The adhesive intermediate layer material for windscreens with head-up displays is usually wedge-shaped to reduce the occurrence of ghost images due to reflections from the inner and outer surfaces of the windscreen.

[0124] As is conventionally known in this industry, glass sheets are typically about 1-3 mm thick, and PVB sheets are about 0.76 mm thick. The glass may be soda-lime silicate glass, for example, having the composition of clear float glass, and usually having iron oxide added as a coloring agent to impart some kind of sunlight control function to the laminated glazing.

[0125] The overall thickness of a windscreen is usually less than 6mm.

[0126] Typically, the composition of soda-lime silicate glass (in wt%) is SiO2 69-74%, Al2O3 0-3%, Na2O 10-16%, K2O 0-5%, MgO 0-6%, CaO 5-14%, SO3 0-2%, and Fe2O3 0.005-2%. The glass composition may also contain other additives, such as refining aids, which are usually present in amounts of up to 2%. The composition of soda-lime silicate glass may also contain other colorants such as Co3O4 and Se, which impart the desired color to the glass when viewed under transmitted light. The color of transmitted glass can be measured according to known standards such as BS EN410.

[0127] Other glass compositions used as inner or outer sheets in laminated glazing for vehicle windscreens are also known in the industry, such as aluminosilicate glass. Such glass sheets are typically used with thicknesses of less than 1 mm, for example, 0.2 mm to 0.9 mm, and may be chemically strengthened.

[0128] As is commonly known in this industry, glass sheets facing the external environment are usually called outer glass sheets, and glass sheets facing the interior of a vehicle are usually called inner glass sheets. Each inner and outer glass sheet has a first principal surface and a second principal surface opposite to it, and when the windscreen is positioned such that the second principal surface of the outer glass sheet faces the first principal surface of the inner glass sheet (when the inner and outer glass sheets are joined by a PVB sheet), the first principal surface of the outer glass sheet is usually called "surface 1", the second principal surface of the outer glass sheet is called "surface 2", the first principal surface of the inner glass sheet is called "surface 3", and the second principal surface of the inner glass sheet is called "surface 4".

[0129] As is clear, "Surface 1" is the outer surface (or outward-facing surface) of the windscreen 1, and "Surface 4" is the inner surface (or inward-facing surface) of the windscreen.

[0130] Vehicle windscreens are typically curved in one or more directions. The radius of curvature in one of these directions may range from 1000 mm to 8000 mm.

[0131] When a vehicle windscreen is curved in two directions, it is preferable that the directions of curvature are perpendicular to each other. The radius of curvature in one or both directions is preferably in the range of 1000 mm to 8000 mm.

[0132] Typically, the "surface 1" of a vehicle windscreen is convex, and the "surface 4" of the windscreen is concave.

[0133] In Figure 2, the windscreen 1 has an inward-facing surface 4, that is, the "surface 4" of the windscreen.

[0134] Typically, light from the head-up display projector 9 is reflected from the portion of the inward-facing surface 4 that defines the first head-up display area 3 and toward the eyebox position 11, thereby creating a virtual image that appears to be behind the windscreen (from the driver's perspective). In some embodiments, the virtual image may be at least partially generated by reflections from other "surfaces 1," "surface 2," or "surface 3" of the windscreen. In some windscreens, an intermediate layer structure joining two glass sheets may be appropriately configured to allow some of the light from the display projector 9 to be directed toward the eyebox position 11. This may be done in addition to, or instead of, the light reflected from any of "surfaces 1," "surface 2," "surface 3," or "surface 4."

[0135] To evaluate the image quality of the first head-up display area 3, the windscreen is typically inspected before being installed in the vehicle. In conventional head-up display areas, a light source is used to illuminate the windscreen, generating a virtual image corresponding to the head-up display image at the projection distance of the virtual image when the windscreen is installed in the vehicle. The displayed image is typically in the form of a characteristic pattern of points and lines, and is distorted so that distortion is corrected by reflection off the curved inner surface of the windscreen, producing a distortion-free virtual image. This virtual image is captured by a camera unit through the windscreen from multiple possible viewpoints of the driver, i.e., different viewpoints within the eyebox. Using these images, the occurrence of optical effects such as distortion and ghost images due to multiple reflections can be evaluated in detail for each different viewpoint within the eyebox.

[0136] When virtual images are captured by a camera unit from different line-of-sight positions within an eyebox, a single camera can be moved between different line-of-sight positions, for example, by mounting it on a robotic arm. Alternatively, multiple cameras corresponding to different line-of-sight positions can be used. In this case, movement during testing is unnecessary, and therefore the cameras are preferably installed statically.

[0137] Images captured by each camera are analyzed using image processing programs known in the industry to determine specific performance parameters for the first head-up display area of ​​the windscreen at each line-of-sight position within the eyebox. These are often simply referred to as the windscreen performance parameters. The overall specific performance parameters may be determined based on the specific performance parameters at each eyebox position.

[0138] Figure 3 is used to illustrate how the method according to the first aspect of the present invention is carried out.

[0139] The windscreen 1, described with reference to Figures 1 and 2, is being tested to evaluate the head-up display performance of a windscreen for use in a vehicle augmented reality head-up display system, and the virtual image has a first projection distance of approximately 10 m from the eyebox position. In Figure 3, axis A-A' is aligned with the eyebox position, and referring to Figure 2, the first projection distance is shown as distance 19.

[0140] The windscreen 1 is held in the desired position for inspection by a suitable fixture 39. The fixture 39 ensures that all measurements are performed with the windscreen 1 (and subsequent windscreens under inspection) held in the same desired measurement position.

[0141] The light source 9' is positioned to direct light in the direction of arrow 10', illuminating the first head-up display area 3 of the windscreen 1.

[0142] Light from light source 9' is reflected by the windscreen 1 and directed towards camera 35. Camera 35 is positioned at the line of sight within the eyebox position. When light from light source 9' strikes the inward-facing "plane 4", a virtual image 13 is generated, which can be captured by camera 35. The virtual image 13 is generated in a first image plane, which is located at a first distance 17 from the eyebox, and the first distance 17 is shorter than the first projection distance 19.

[0143] The light from light source 9' takes the form of a pattern consisting of multiple dots, and Figure 3 shows camera 35 capturing an image of one of these dots, 41. Dot 41 can be called a virtual image element.

[0144] For reference, Figure 3 shows the position of the virtual image 15 at the first projection distance 19 from the eyebox position. The corresponding virtual image element dot 41 (labeled as dot 41' within the virtual image 15) is also shown.

[0145] The inspection method according to the present invention captures a virtual image 13 at a first distance 17, where the first distance 17 is different from the first projection distance 19. In this embodiment, the first distance 17 is shorter than the first projection distance 19. As shown in Figure 3, the windscreen 1 is inspected using the virtual image 13 in a different positional relationship than the virtual image 15 generated when the windscreen 1 is attached to the vehicle, and although the same first head-up display area 3 is illuminating and virtual images 13 and 15 are generated, the position of the virtual image relative to the windscreen 1 is different.

[0146] The light projected onto the first head-up display area 3 is in the form of a distorted reference image (or pattern). The amount of distortion applied to the reference image may be determined in part based on the shape of the windscreen and / or other optical components used to project light from the light source 9' onto the first head-up display area 3. When the projected image is reflected by the inward-facing surface 4 of the windscreen 1, the distorted projected image itself is further distorted, and the virtual image 13 produced in the first image plane is ideally identical to the original, undistorted reference image. By evaluating how much the virtual image deviates from the undistorted reference image, the performance parameters of the windscreen can be determined against a given standard or applicable performance specification.

[0147] According to one embodiment of the present invention, the first distance 17 during inspection of the windscreen 1 is shorter than the first projection distance 19. In this example, the first projection distance 19 is approximately 10 m, and the first distance 17 is approximately 2 m.

[0148] Surprisingly, the inventors found a good correlation between the performance parameters determined from measurements taken at a first distance 17 and the corresponding performance parameters determined from measurements taken at a first projection distance 19. This correlation makes it possible to define performance specifications for the performance parameters of the first head-up display area of ​​the windscreen, which are determined from measurements taken at a first distance (not the first projection distance). This simplifies the inspection step, as it eliminates the need to take measurements at the first projection distance, and measurements only need to be taken at the first distance, which may be much shorter than the first projection distance.

[0149] Refer to Figure 4 to see the correlation between the performance parameters measured when a virtual image was generated at approximately 2m and the performance parameters measured when a virtual image was generated at approximately 10m.

[0150] Figure 4 shows a comparison between the measured height of a virtual image element within a virtual image at a projection distance of approximately 10 m (axis 31) and the measured height of the corresponding virtual image element at a projection distance of approximately 2 m (axis 33).

[0151] A good correlation can be confirmed. This makes it possible to define appropriate performance specifications at 2m (i.e., the first distance) to evaluate the quality of glazing. Furthermore, this correlation makes it possible to determine a formula or correction factor for converting the height of the virtual image element measured in the first image plane to the calculated height in the second image plane (which may be at the first projection distance). If necessary, the performance specifications can be based on the converted performance parameters at the second distance (which may be the projection distance) instead of the performance parameters measured at the first distance.

[0152] Returning to Figure 3, the camera 35 communicates with the computer 38 via the appropriate cable 38a.

[0153] Furthermore, the computer 38 can also communicate with the light source 9' via a suitable cable 38b and control the pattern projected onto the inner surface 4 of the windscreen 1. Different patterns may be used for windscreens of different types of vehicles.

[0154] The computer 38 includes software for analyzing the virtual image 13 captured by the camera 35 to determine specific performance parameters of the head-up display area 3 of the windscreen 1. Next, it compares this to the performance specifications of the specific performance parameters at a first distance 17 to determine whether the windscreen 1 has the appropriate performance for use in a vehicle's head-up display system.

[0155] Camera 35 can capture one or more images of the virtual image 13 in the first image plane, and can image the entire virtual image generated by reflected light from the entire first head-up display area 3. Camera 35 can be positioned at different eye positions within the eyebox and can capture images at each eye position. Images captured at each eye position within the eyebox can be used to determine specific performance parameters at each eyebox position. This will be further explained with reference to Figures 5 and 6.

[0156] Referring to Figures 3, 5, and 6, in order to measure the performance of the first head-up display area 3 of the windscreen 1, at least the entire first head-up display area 3 is illuminated with light from the light source 9'. In this example, the outer perimeter of the illuminated area is shown by the dotted line 21 and includes the entire first head-up display area 3.

[0157] The measurement of the virtual image 13 performed by camera 35 in the first image plane may result in a single captured image. However, due to the size of the virtual image 13 in the first image plane, multiple images are typically captured using an appropriate imaging system that may include multiple cameras at different eye positions within the eyebox, and / or cameras movable to each eye position within the eyebox. In this example, camera 35 is movable to six different eye positions within the eyebox and is used to capture six images 25a, 25b, 25c, 25d, 25e, and 25f. Instead of movable cameras, six fixed cameras could be placed at desired eye positions within the eyebox to capture images 25a, 25b, 25c, 25d, 25e, and 25f.

[0158] For specific performance parameters, each individual image 25a, 25b, 25c, 25d, 25e, and 25f can be used to determine the specific performance parameters corresponding to each of the virtual image portions.

[0159] The six images 25a, 25b, 25c, 25d, 25e, and 25f make it possible to construct the entire virtual image resulting from the reflection from the entire first head-up display area 3.

[0160] If necessary, performance parameters can be determined using a constituent image of the entire virtual image resulting from reflections from the entire first head-up display area 3.

[0161] The method according to the present invention can also be used to inspect glazing of vehicle windscreens and the like having two (or more) head-up display areas. Measurement of the performance parameters of different head-up display areas of glazing can be performed using virtual images generated at the same distance from the eyebox position for each different head-up display area when the glazing is installed in the vehicle. This requires appropriately illuminating each different head-up display area to generate virtual images at the same distance from the eyebox position for measurement of each different head-up display area, but when the glazing is installed in the vehicle, each different head-up display area has a different projection distance.

[0162] According to the present invention, such glazing can be inspected without using a virtual image projected at a projection distance of any head-up display area.

[0163] For example, if a windscreen has a first head-up display area for an augmented reality head-up display system, where the projection distance from the eyebox position may be about 10 m, and a second head-up display area for a conventional head-up display system, where the projection distance from the eyebox position may be about 2 m, then according to the present invention, the performance parameters of the glazing second head-up display area can be measured using a virtual image generated at 2 m, and the performance parameters of the glazing first head-up display area can also be measured using a virtual image generated at 2 m.

[0164] The performance parameters of the first head-up display area differ from those measured at 10m when measured using a virtual image at 2m (not 10m). However, as shown in Figure 4, a good correlation is obtained, allowing for the determination of appropriate performance specifications for the performance parameters of the first head-up display area when measured using a virtual image at 2m (not 10m).

[0165] By using a suitable virtual image 2m from the eyebox position, the performance parameters of the second head-up display area can be measured at the projection distance of a conventional head-up display system, which may be desirable.

[0166] However, the performance parameters of the second head-up display area may be measured using a virtual image at a different distance from the eyebox position, for example, greater than 1 m or 2 m, and shorter than the projection distance of the augmented reality head-up display system (i.e., 10 m). As the distance of the virtual image used in the method according to the present invention approaches the projection distance of the augmented reality head-up display system, the advantages of the present invention may be reduced.

[0167] When using the present invention to inspect glazing having at least first and second head-up display areas having different projection distances from the eyebox position, if the projection distance of the first head-up display area is longer than that of the second head-up display area, it is advantageous to inspect the glazing using a virtual image at or below the projection distance of the second head-up display area. This is particularly advantageous when the projection distance of the first head-up display area is greater than 5m but less than 20m, and the projection distance of the second head-up display area is greater than 1m but less than 5m.

[0168] In another embodiment of the present invention, as described above, a windscreen having a first head-up display area for an augmented reality head-up display system with a projection distance of about 10 m from the eyebox position and a second head-up display area for a conventional head-up display system with a projection distance of about 2 m from the eyebox position can be inspected using a virtual image generated in an image plane beyond 10 m from the eyebox position. However, this is undesirable because the aforementioned difficulties arise as the virtual image moves away from the eyebox position.

[0169] Furthermore, it is clear that the method according to the present invention can also be used for inspecting glazing having three or more head-up display areas, for example, three or more head-up display areas.

[0170] The present invention has the following aspects.

[0171] Embodiment 1. A method for inspecting glazing, configured to be mounted on a vehicle having a head-up display projector, wherein, during use, light from the head-up display projector illuminates a first head-up display area of ​​the glazing and generates a first virtual image at a first projection distance from the eyebox position, the method for inspecting glazing comprising: (i) positioning the glazing with respect to a light source; (iii) illuminating at least a portion of the first head-up display area of ​​the glazing with light from the light source to generate a first virtual image on a first image plane, the first image plane being at a first distance from the eyebox position; (iii) capturing a first image of the first virtual image on the first image plane using an imaging system; and (iv) determining at least first performance parameters of the first head-up display area of ​​the glazing using a first image of the first virtual image on the first image plane, wherein the first distance is different from the first projection distance.

[0172] Embodiment 2. The method according to Embodiment 1, wherein the first performance parameter determined in (iv) is compared with an appropriate performance specification.

[0173] Embodiment 3. The method according to Embodiment 2, wherein the appropriate performance specification is the range of a first performance parameter at a first distance.

[0174] Embodiment 4. A method according to any one of Embodiments 1 to 3, wherein the first projection distance exceeds 3 m, more preferably exceeds 5 m, and even more preferably exceeds 7 m.

[0175] Embodiment 5. A method according to any one of Embodiments 1 to 4, wherein the first projection distance is less than 150 m, more preferably less than 50 m, even more preferably less than 20 m, and even more preferably less than 15 m.

[0176] Embodiment 6. A method according to any one of Embodiments 1 to 5, wherein the first distance is about 4 m or less, preferably about 3 m or less, and more preferably about 2.5 m or less.

[0177] Embodiment 7. A method according to any one of Embodiments 1 to 6, wherein the first distance exceeds about 0.5 m, preferably about 1 m.

[0178] Embodiment 8. A method according to any of Embodiments 1 to 7, wherein the first distance is shorter than the first projection distance, the first projection distance is 7m to 150m, and the first distance is 1m to 30m.

[0179] Embodiment 9. A method according to any one of Embodiments 1 to 8, wherein the first projection distance is 7 m to 15 m and the first distance is 1 m to 3 m.

[0180] Embodiment 10. A method according to any one of Embodiments 1 to 9, wherein the first head-up display area is for an augmented reality head-up display system.

[0181] Embodiment 11. A method according to any one of Embodiments 1 to 10, wherein the first head-up display area is at least about 5% of the glazing area.

[0182] Embodiment 12. A method according to any one of Embodiments 1 to 11, wherein the first head-up display area is less than about 50% of the glazing area, preferably less than about 25%.

[0183] Embodiment 13. A method according to any one of Embodiments 1 to 12, wherein the glazing is a windscreen.

[0184] Embodiment 14. A method according to any of Embodiments 1 to 13, wherein the glazing is a windscreen for an automobile, train, aircraft, or water vehicle.

[0185] Embodiment 15. A method according to any one of Embodiments 1 to 14, wherein the glazing comprises a first glazing material plate joined to a second glazing material plate by an intermediate layer structure comprising at least one sheet of adhesive intermediate layer material, the second glazing material plate being an inner sheet facing the interior of the vehicle when the glazing is attached to the vehicle, the first glazing material plate being an outer sheet facing the external environment when the glazing is attached to the vehicle, the inner sheet having a main surface facing the interior of the vehicle when the glazing is attached to the vehicle, and the outer sheet having an outer surface facing the external environment of the vehicle to which the glazing is attached.

[0186] Embodiment 16. A method according to any one of Embodiments 1 to 15, wherein the imaging system comprises at least one camera.

[0187] Embodiment 17. A method according to any one of Embodiments 1 to 16, wherein the imaging system comprises at least one fixed camera for capturing images of a first virtual image from each fixed eye position in an eye box.

[0188] Embodiment 18. A method according to any one of Embodiments 1 to 17, wherein the imaging system comprises at least one movable camera for capturing an image of a first virtual image from a first eye position in an eye box, the movable camera being able to move to a second eye position to capture a different image of the first virtual image.

[0189] Embodiment 19. A method according to any one of Embodiments 1 to 18, wherein a first image of a first virtual image is captured with the camera positioned at the eyebox.

[0190] Embodiment 20. A method according to any one of Embodiments 1 to 19, wherein a first image of a first virtual image is captured with the camera positioned at a first eye position within the eye box.

[0191] Embodiment 21. A method according to any one of Embodiments 1 to 20, wherein the eyebox position has multiple eye positions.

[0192] Embodiment 22. A method according to any one of Embodiments 1 to 21, wherein the light source is a display.

[0193] Embodiment 23. A method according to any one of Embodiments 1 to 22, wherein the light source comprises a patterned aperture that is back-illuminated by a planar light source.

[0194] Embodiment 24. A method according to any one of Embodiments 1 to 23, wherein the first virtual image is configured to be parallel to the first virtual image at a first projection distance of the head-up display system.

[0195] Embodiment 25. A method according to any of Embodiments 1 to 24, wherein the first distance is shorter than the first projection distance.

[0196] Appearance 26. A method according to any one of Appearances 1 to 25, wherein the first projection distance is greater than x m, and x = 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, or 100.

[0197] Embodiment 27. The method according to any one of Embodiments 1 to 26, wherein the first projection distance is less than ym and y = 110, 100, 90, 80, 70, 60, 50, 40, or 30.

[0198] Embodiment 28. A method according to any of Embodiments 1 to 27, wherein the first projection distance is 5 m to 15 m.

[0199] Embodiment 29. A method according to any of Embodiments 1 to 28, wherein the first distance is less than or equal to jm, and j = 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, or 0.5.

[0200] Embodiment 30. A method according to any of Embodiments 1 to 29, wherein the first distance is km or greater, and k = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.

[0201] Embodiment 31. A method according to any of Embodiments 1 to 30, wherein the first distance is 0.5 m to 5 m, more preferably 0.5 m to 4 m, and even more preferably 0.5 m to 3 m.

[0202] Embodiment 32. A method according to any one of Embodiments 1 to 24, wherein the first distance is longer than the first projection distance.

[0203] Embodiment 33. The method according to Embodiment 32, wherein the first distance is greater than x'm and x' = 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, or 100.

[0204] Embodiment 34. The method according to Embodiment 32 or 33, wherein the first distance is less than y'm and y' = 110, 100, 90, 80, 70, 60, 50, 40, or 30.

[0205] Embodiment 35. A method according to any one of Embodiments 32 to 34, wherein the first distance is 5m to 15m.

[0206] Embodiment 36. A method according to any of Embodiments 32 to 35, wherein the first projection distance is less than or equal to j'm, and j' = 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1, or 0.5.

[0207] Embodiment 37. A method according to any of Embodiments 32 to 36, wherein the first projection distance is k'm or greater, and k' = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.

[0208] Embodiment 38. A method according to any one of Embodiments 32 to 37, wherein the first projection distance is 0.5 m to 5 m, more preferably 0.5 m to 4 m, and even more preferably 0.5 m to 3 m.

[0209] Embodiment 39. A method according to any one of Embodiments 1 to 25 or 32, wherein the first projection distance exceeds 20 m.

[0210] Apparatus 40. The method according to Apparatus 39, wherein the first projection distance is greater than x''m and x'' = 30, 40, 50, 60, 70, 80, 90, or 100.

[0211] Apparatus 41. The method according to Apparatus 39 or 40, wherein the first projection distance is less than y''m and y'' = 110, 100, 90, 80, 70, 60, 50, 40, or 30.

[0212] Embodiment 42. A method according to any one of Embodiments 1 to 41, wherein a first image of a first virtual image is captured with the imaging system positioned at the eyebox location.

[0213] Embodiment 43. A method according to any one of Embodiments 1 to 42, wherein a first image of a first virtual image is captured with the camera positioned at the eyebox.

[0214] Embodiment 44. A method according to any one of Embodiments 1 to 43, wherein a first image of a first virtual image is captured with the camera positioned at a first eye position within the eye box.

[0215] Embodiment 45. A method according to any one of Embodiments 1 to 44, wherein a first image of a first virtual image is captured at a first eye position in an eye box.

[0216] Embodiment 46. A method according to Embodiment 45, the method comprising the steps of capturing a second image of a first virtual image in a first image plane at a second eye position in an eye box, and determining a first performance coefficient using the second image of the first virtual image.

[0217] Embodiment 47. A method according to any one of Embodiments 1 to 46, wherein multiple images of a first virtual image captured at different eye positions in multiple eye boxes are captured.

[0218] Embodiment 48. The method according to Embodiment 48, wherein each of a plurality of images is used to determine a corresponding first performance parameter.

[0219] Embodiment 49. A method according to Embodiment 47 or 48, wherein each image is used to construct a first virtual image, and the constructed first virtual image is used to determine a first performance parameter.

[0220] Embodiment 50. A method according to any one of Embodiments 1 to 49, wherein the glazing comprises a first glazing material plate to which a second glazing material plate is joined by an intermediate layer structure comprising at least one sheet of adhesive intermediate layer material, the second glazing material plate being an inner sheet facing inward when the glazing is attached to the vehicle, the inner sheet having an inner surface facing inward when the glazing is attached to the vehicle, and the first virtual image produced comprises reflected light from at least the inner surface of the inner sheet.

[0221] Embodiment 51. The method according to Embodiment 50, wherein the first glazing material plate is an outer sheet facing the external environment of the vehicle to which the glazing is attached, and the outer sheet has an outer surface facing the external environment of the vehicle to which the glazing is attached.

[0222] Embodiment 52. A method according to Embodiment 50 or 51, wherein the first virtual image produced comprises reflected light from at least an intermediate layer structure.

[0223] Embodiment 53. A method according to any one of Embodiments 50 to 52, wherein the first virtual image generated in these embodiments comprises at least reflected light from an outer surface.

[0224] Embodiment 54. A method according to any one of Embodiments 1 to 53, wherein the imaging system comprises a first camera at a first eye position in an eye box for capturing a first image of a first virtual image, and a second camera at a second eye position in an eye box for capturing a second image of a first virtual image.

[0225] Embodiment 55. A method according to any one of Embodiments 1 to 53, wherein the imaging system is movable relative to the glazing, and a first image is captured by positioning the imaging system at a first position relative to the glazing, and a second image is captured by positioning the imaging system at a second position relative to the glazing.

[0226] Apparatus 56. The method according to Apparatus 55, wherein the first image is captured at a first eye position in the eye box.

[0227] Embodiment 57. The method according to Embodiment 55 or 57, wherein the imaging system is moved to a second position relative to glazing.

[0228] Embodiment 58. A method according to any one of Embodiments 55 to 57, wherein the second image is captured at a second position within the eyebox.

[0229] Embodiment 59. A method according to any of Embodiments 55 to 58, wherein multiple images are captured to form an overall first virtual image.

[0230] Embodiment 60. A method according to any one of Embodiments 1 to 59, wherein the light from a light source is patterned, preferably comprising at least one dot and / or at least one line.

[0231] Apparatus 61. The method according to Apparatus 60, wherein the pattern is specific to glazing inspection for a particular vehicle model.

[0232] Embodiment 62. A method according to any one of Embodiments 1 to 61, wherein the light from a light source is patterned, a first virtual image of the pattern on a first image plane is distorted by glazing, and when determining the performance parameters of glazing, the first virtual image distorted by glazing is compared with a reference image of the pattern.

[0233] Apparatus 63. The method according to Apparatus 62, wherein the reference image is an undistorted image and is distorted for projection onto the glazing of the object to be inspected.

[0234] Embodiment 64. A method according to any one of Embodiments 1 to 63, wherein a first performance parameter of a first head-up display area of ​​glazing is determined using only a first image of a first virtual image.

[0235] Embodiment 65. The method according to Embodiment 64, wherein a first image of a first virtual image is captured with the imaging system positioned at a first eye position within the eye box.

[0236] Apparatus 66. The method according to any one of Apparatus 1 to 65, wherein (ii) light from a light source illuminates at least the entire area of ​​the first head-up display.

[0237] Apparatus 67. The method of Apparatus 66, wherein in (iii), an entire first virtual image is captured from a first fully illuminated head-up display area, and the captured first image is an image of the entire first virtual image.

[0238] Apparatus 68. The method of Apparatus 66, wherein in (iii), only a portion of the entire virtual image from a fully illuminated first head-up display area is captured as the first image.

[0239] Embodiment 69. The method according to Embodiment 66, wherein the image of the entire virtual image from a first head-up display area is composed of a plurality of images, and each of the plurality of images from the first head-up display area is an image of a different part of the entire virtual image.

[0240] Embodiment 70. A method according to any one of Embodiments 1 to 65, wherein the performance of the entire first head-up display area is determined by performing (ii) and (iii) multiple times to illuminate multiple different portions of the first head-up display area of ​​glazing.

[0241] Embodiment 71. The method according to Embodiment 70, wherein each portion of the first head-up display area is illuminated individually.

[0242] Embodiment 72. A method according to Embodiment 70 or 71, wherein each different part is used to determine a corresponding first performance parameter.

[0243] Embodiment 73. A method according to any one of Embodiments 70 to 72, wherein each first image for each different illuminated portion is used to constitute an overall virtual image from a first head-up display area.

[0244] Embodiment 74. A method according to Embodiment 73, wherein an image of the entire virtual image from a first head-up display area with such configuration is used to determine a first performance parameter of the first head-up display area of ​​glazing.

[0245] Embodiment 75. A method according to any one of Embodiments 1 to 74, wherein the glazing is configured to be mounted on a vehicle, and during use, light from a head-up display projector illuminates a second head-up display area of ​​the glazing to generate a virtual image at a second projection distance from the eyebox position, wherein the second projection distance is shorter than the first projection distance.

[0246] Embodiment 76. A method according to Embodiment 75, wherein the glazing inspection method comprises the step of inspecting a second head-up display area and determining at least a first performance parameter of the second head-up display area of ​​the glazing.

[0247] Embodiment 77. A method according to Embodiment 76, wherein the method for inspecting a second head-up display area comprises the steps of: irradiating at least a portion of a second head-up display area of ​​glazing with light from a light source or other light source to generate a second virtual image on a second image plane, the second image plane being a second distance from the eyebox position; capturing a first image of the second virtual image on the second image plane using an imaging system; and determining at least first performance parameters of a second head-up display area of ​​glazing using the first image of the second virtual image.

[0248] Apparatus 78. The method according to Apparatus 77, wherein a first performance parameter of a second head-up display area is compared with a suitable performance specification.

[0249] Embodiment 79. A method according to any one of Embodiments 75 to 78, wherein the second distance from the eyebox position of the second image plane is the same as the first distance from the eyebox position of the first image plane.

[0250] Embodiment 80. A method according to any one of Embodiments 75 to 79, wherein the second distance is the same as the second projection distance.

[0251] Embodiment 81. A method according to any one of Embodiments 75 to 80, wherein the first projection distance is 5 m to 20 m and the second projection distance is 1 m to 5 m.

[0252] Apparatus 82. The method according to any one of Apparatus 75 to 81, wherein a first head-up display area of ​​glazing has a first area, and a second head-up display area of ​​glazing has a second area, and the first area is greater than the second area.

[0253] Embodiment 83. A method according to Embodiment 82, wherein the first area is at least 1.5 times, preferably 2 times, and more preferably 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times, or 10 times, the second area.

[0254] Embodiment 84. A method according to Embodiment 82 or 83, wherein the first area is less than 20 times the second area.

[0255] Apparatus 85. A method according to any one of Apparatus 75 to 84, wherein the first domain is for an augmented reality head-up display system and the second domain is for a conventional head-up display system.

[0256] Embodiment 87. A method according to any one of Embodiments 1 to 74, wherein the method is configured so that the glazing is mounted on a vehicle, and during use, light from a head-up display projector illuminates a second head-up display area of ​​the glazing to generate a second virtual image at a second projection distance from the eyebox position, and the method is used for inspecting glazing where the second projection distance is longer than the first projection distance.

[0257] Embodiment 88. A method according to Embodiment 87, wherein the glazing inspection method includes the step of inspecting a second head-up display area and determining at least a first performance parameter of the second head-up display area of ​​the glazing.

[0258] Embodiment 89. A method according to Embodiment 88, wherein the method for inspecting a second head-up display area comprises the steps of: irradiating at least a portion of a second head-up display area of ​​glazing with light from a light source or other light source to generate a second virtual image on a second image plane, the second image plane being a second distance from the eyebox position; capturing a first image of the second virtual image on the second image plane using an imaging system; and determining at least first performance parameters of a second head-up display area of ​​glazing using the first image of the second virtual image.

[0259] Apparatus 90. The method according to Apparatus 89, wherein a first performance parameter of a second head-up display area is compared with a suitable performance specification.

[0260] Embodiment 91. A method according to any one of Embodiments 87 to 90, wherein the second distance from the eyebox position of the second image plane is the same as the first distance from the eyebox position of the first image plane.

[0261] Embodiment 92. A method according to any one of Embodiments 87 to 91, wherein the first distance is the same as the second projection distance.

[0262] Embodiment 93. A method according to any one of Embodiments 1 to 92, the method comprising a calibration step, wherein in (iv), a first performance parameter measured in a first image plane can be converted to a corresponding first performance parameter at a first projection distance or other projection distance from an eyebox position using at least a first correction coefficient determined in the calibration step.

[0263] Apparatus 94. The method of Apparatus 93, wherein a first correction coefficient is determined using ray tracing or measurement of a first performance parameter of a reference virtual image generated at a first image plane and a first projection distance or other distance.

[0264] Embodiment 95. A method according to Embodiment 94 or 95, wherein the first correction coefficient includes a coefficient for transforming at least ghosting, distortion, magnification, aspect ratio, and displacement.

[0265] Apparatus 96. A method according to any one of Apparatus 1 to 95, wherein the first performance parameter of the first head-up display area of ​​glazing relates to ghosting, distortion, magnification, aspect ratio, or displacement.

[0266] Embodiment 97. A method according to any one of Embodiments 1 to 96, wherein the first virtual image at a first distance is configured to be parallel to the first virtual image at a first projection distance of the head-up display system.

[0267] Embodiment 98. A method according to any one of Embodiments 1 to 97, wherein the first virtual image at a first distance is configured to be parallel to the eyebox position.

[0268] Embodiment 99. A method according to any one of Embodiments 1 to 98, wherein a glazing is attached to a vehicle, and light from a head-up display projector illuminates a first head-up display area of ​​the glazing to generate a first virtual image at a first projection distance from the eyebox position, wherein the first virtual image at the first projection distance is part of an inclined virtual image inclined with respect to the eyebox position.

[0269] Embodiment 100. A method according to any one of Embodiments 1 to 99, wherein the glazing is mounted on a vehicle, and when in use, light from a head-up display projector illuminates a second head-up display area of ​​the glazing, generating a second virtual image at a second projection distance from the eyebox position.

[0270] Embodiment 101. A method according to any one of Embodiments 1 to 100, wherein the first virtual image at a first projection distance is part of an inclined virtual image inclined with respect to the eyebox position.

[0271] Embodiment 102. A method according to any one of Embodiments 1 to 101, wherein the first virtual image at a first projection distance is part of an inclined virtual image set to be inclined forward with respect to the vertical direction of the vehicle.

[0272] Embodiment 103. A glazing inspection apparatus configured to be mounted on a vehicle having a head-up display projector, wherein, during use, light from the head-up display projector illuminates a first head-up display area of ​​the glazing and generates a first virtual image at a first projection distance from the eyebox position, the apparatus comprising a fixture, a light source, an imaging system and a computer, the fixture being positioned relative to the light source and configured to hold a windscreen during inspection measurement, the light from the light source striking the glazing and generating a virtual image in a first image plane, the first image plane being at a first distance from the eyebox position, the imaging system being positioned relative to the glazing during the inspection step and capturing an image of the virtual image in the first image plane through the glazing, the computer having a program for analyzing the captured image of the virtual image in the first image plane to determine at least first performance parameters of the glazing, the first image plane being at a position different from the first projection distance, the glazing inspection apparatus.

[0273] Embodiment 104. The apparatus according to Embodiment 103, wherein the imaging system is positioned at the eyebox location.

[0274] Apparatus 105. Apparatus according to Apparatus 103 or 104, wherein the imaging system comprises at least one fixed camera and / or at least one movable camera.

Claims

1. A method for inspecting glazing for use in a head-up display system, wherein the glazing is configured to be mounted on a vehicle having a head-up display projector, and as a result, when in use, light from the head-up display projector illuminates a first head-up display area of ​​the glazing, generating a first virtual image at a first projection distance from the eyebox position, and the method is as follows: (i) The step of positioning the glazing relative to the light source, (ii) A step of irradiating light from the light source toward at least a portion of the first head-up display area of ​​the glazing to generate a first virtual image on a first image plane, wherein the first image plane is at a first distance from the eyebox position, (iii) The steps of capturing the first virtual image in the first image plane with an imaging system and capturing a first image of the virtual image in the first image plane, (iv) A step of determining at least a first performance parameter of the first head-up display area of ​​the glazing using the first image of the first virtual image in the first image plane, Includes, The first distance is different from the first projection distance. A method for inspecting glazing for use in head-up display systems.

2. The method according to claim 1, wherein the first performance parameter of the first head-up display area of ​​the glazing is compared with appropriate performance specifications.

3. The method according to claim 1 or 2, wherein the first distance is shorter than the first projection distance.

4. The method according to any one of claims 1 to 3, wherein the first projection distance is greater than 3 m, preferably greater than 5 m, and more preferably greater than 7 m.

5. The method according to any one of claims 1 to 4, wherein the first projection distance is less than 150 m, more preferably less than 50 m, even more preferably less than 20 m, and even more preferably less than 15 m.

6. The method according to any one of claims 1 to 5, wherein the first distance is less than 4 m, preferably less than 3 m, and more preferably less than 2.5 m.

7. The method according to claims 1 to 6, wherein the first distance is greater than 0.5 m, preferably greater than 1 m.

8. The method according to any one of claims 1 to 7, wherein the first projection distance is 7 m to 15 m, and the first distance is 1 m to 3 m.

9. The method according to claim 1 or 2, wherein the first distance is longer than the first projection distance.

10. The method according to claim 9, wherein the first distance is 5 m to 15 m, and / or the first projection distance is 0.5 m to 5 m.

11. The method according to any one of claims 1 to 10, wherein the first head-up display area is for an augmented reality head-up display system.

12. The method according to any one of claims 1 to 11, wherein the first head-up display area is at least about 5% of the glazing area.

13. The method according to any one of claims 1 to 12, wherein the first head-up display area is less than about 50% of the glazing area, more preferably less than about 25%.

14. The method according to any one of claims 1 to 13, wherein in step (ii), the light from the light source illuminates at least the entire first head-up display area.

15. The method according to claim 14, wherein in step (iii), the entire virtual image from the first head-up display area is captured to generate the first image.

16. The method according to claim 14, wherein, after step (ii), the first virtual image is imaged and at least a second image is captured, the second image being a portion of the first virtual image different from the first image, preferably the first image overlapping at least partially with the second image.

17. The method according to claim 16, wherein a first performance parameter is determined for each of the first image and the second image.

18. The method according to any one of claims 1 to 17, wherein the performance of the entire first head-up display area is determined by performing steps (ii) and (iii) multiple times to illuminate multiple different portions of the glazing's first head-up display area.

19. The method according to claim 18, wherein each portion of the first head-up display area is illuminated individually.

20. The method according to claim 18 or 19, wherein each different part is used to determine its respective first performance parameter.

21. The method according to any one of claims 1 to 13, wherein steps (ii) and (iii) are repeated multiple times, and the resulting multiple first images are used to constitute an image of the entire first virtual image from the first head-up display area.

22. The method according to any one of claims 1 to 21, wherein the glazing is configured to be mounted on a vehicle, and as a result, when in use, light from the head-up display projector illuminates a second head-up display area of ​​the glazing, generating a second virtual image at a second projection distance from the eyebox position, the second projection distance being different from the first projection distance.

23. The method according to claim 22, comprising the step of inspecting the second head-up display area and determining at least a first performance parameter of the second head-up display area of ​​the glazing.

24. The method for inspecting the second head-up display area, comprising the steps of: irradiating at least a portion of the second head-up display area of ​​the glazing with light from the light source or other light source to generate a second virtual image on a second image plane, wherein the second image plane is a second distance from the eyebox position; capturing the second virtual image on the second image plane with an imaging system to capture a first image of the second virtual image; and determining at least a first performance parameter of the second head-up display area of ​​the glazing using the first image of the second virtual image.

25. The method according to claim 24, wherein the first performance parameter of the second head-up display area of ​​the glazing is compared with appropriate performance specifications.

26. The method according to claim 24 or 25, wherein the second distance from the eyebox position in the second image plane is the same as the first distance from the eyebox position in the first image plane.

27. The method according to any one of claims 22 to 26, wherein the first distance is the same as the second projection distance.

28. The method according to any one of claims 22 to 27, wherein the second projection distance is longer than the first projection distance.

29. The method according to any one of claims 22 to 27, wherein the second projection distance is shorter than the first projection distance.

30. The method according to any one of claims 22 to 27, wherein the first projection distance is 5 m to 20 m, and the second projection distance is 1 m to 5 m.

31. The method according to any one of claims 1 to 30, wherein the first performance parameter of the first head-up display area of ​​the glazing relates to ghosting, distortion, magnification, aspect ratio, or displacement.

32. The method according to any one of claims 1 to 31, wherein the first virtual image at the first projection distance is a part of an inclined virtual image, and the inclined virtual image is inclined with respect to the position of the eye box.

33. The method according to any one of claims 1 to 32, wherein the first virtual image at the first projection distance is a part of an inclined virtual image set to be inclined forward with respect to the vertical direction of the vehicle.

34. A glazing inspection device, wherein the glazing is configured to be mounted on a vehicle having a head-up display projector, and as a result, when in use, light from the head-up display projector illuminates a first head-up display area of ​​the glazing, generating a first virtual image at a first projection distance from the eyebox position, and the device, Equipped with a jig, light source, imaging system and computer, The fixture is positioned relative to the light source and configured to hold the windscreen during inspection and measurement, so that light from the light source strikes the glazing and generates a virtual image on the first image plane. The first image plane is a first distance from the eyebox position, The imaging system is positioned relative to the glazing during the inspection step and captures an image of the virtual image in the first image plane through the glazing. The computer has a program for analyzing the captured image of the virtual image in the first image plane and determining at least a first performance parameter of the glazing. The first image plane is located at a position different from the first projection distance. A device for inspecting glazing.

35. The imaging system is located at the eyebox position, as described in claim 34.

Images