Method and system for determining the optical quality of a plurality of glass panels intended to be provided in vehicles

Abstract

The invention relates to a method for determining the optical quality of a plurality of glass panels intended to be provided in vehicles and corresponding to a single model. The method comprises, for a single determined area of each of these glass panels, steps of: - obtaining (E10_i) at least one optical aberration map; and - for each optical aberration map, determining (E20_i) an amplitude of the associated optical aberration, the method further comprising steps of: - for each optical aberration, determining (E30) an average amplitude on the basis of amplitudes determined for the optical aberration and for each of the glass panels, respectively; and - selecting (E40), from the average amplitudes determined, optical aberrations that comply with a determined selection criterion.

Description

Method and system for determining the optical quality of a plurality of glazings intended to equip vehicles

[0001] The present invention belongs to the general field of optical quality control of glazing.

[0002] It relates more particularly to a method for determining the optical quality of a plurality of glazings intended to equip vehicles, and a system configured to implement such a method. It also relates to a method for manufacturing an optical system from data obtained using the method for determining optical defects, as well as glazing and a vehicle driving assistance system each incorporating such an optical system. The invention finds a particularly advantageous, although in no way limiting, application in assisting the driving of transport vehicles (passengers, goods) comprising a passenger compartment.

[0003] Intelligent driver assistance systems (ADAS) (acronym for "Advanced Driver Assistance System") are increasingly being fitted to transport vehicles, particularly road vehicles.

[0004] Conventionally, these on-board ADAS systems are configured to provide, particularly in real time, useful information for assisting vehicle drivers. To do this, these systems include one or more image acquisition devices for collecting data on the environment around the vehicle. The data thus acquired is processed by systems whose hardware and software configuration allows for obtaining a desired functionality.

[0005] For example, a night driving assistance system allows a video of the outside environment to be displayed in real time on the vehicle's dashboard via an infrared camera. In another example, an autonomous driving system processes the images acquired by a camera in order to extract data needed by the vehicle's automatic pilot unit.

[0006] In order to protect the image acquisition devices from the external environment, these devices are generally placed inside the vehicle, i.e. within a passenger compartment of said vehicle, most often behind the windshield in order to acquire information from the front of the vehicle. They can also be placed in other locations, for example behind the rear window or even a side window.

[0007] It follows from the above considerations that the proper functioning of intelligent ADAS systems relies in particular on the reliability of the data provided by the image acquisition devices with which they are equipped. However, the positioning of the image acquisition devices behind one of the vehicle's windows implies that the light rays they receive initially pass through the window in question. In other words, the reliability of the data provided by the image acquisition devices itself depends on the optical quality of the windows, the latter having to be sufficient to prevent a captured image from being distorted to an extent that hinders or prevents its processing.

[0008] The optical quality of glazing is assessed according to various criteria, including the existence or absence of optical defects that cause harmful artifacts in the images acquired by image acquisition devices. The origins of these optical defects can be diverse: inclination of the glazing, presence of opaque elements (generally enamels) allowing part of the elements of the image acquisition devices to be hidden (except the active elements for image acquisition) so that they are not visible from outside the vehicles, local variations in the surface of the glass, presence of functional elements such as networks of heating wires or thin layers with optical or thermal properties, etc.

[0009] For a long time, the techniques used to assess the optical quality of glazing, particularly those based on the principle of deflectometry, were far from effective insofar as they did not allow for the precise identification and quantification of optical defects that affect the quality of images captured by image acquisition devices. In particular, these techniques were deficient in qualifying defects leading to the appearance of optical aberrations in the acquired images.

[0010] A more recent solution, described in document WO 2021 / 110901, overcomes some of these difficulties by proposing a method for measuring the optical quality of a glazing unit based on the analysis of the wavefront of light rays transmitted by a given area of ​​a glazing unit, so as to generate optical defect maps, in particular optical aberration maps specific to this glazing unit. This solution is nonetheless deficient insofar as the results it provides for a given first glazing unit do not apply to a given second glazing unit, even if these first and second glazing units come from the same model. In other words, if one seeks to compensate for the defects of several glazing units by appropriate optical systems, the solution of document WO 2021 / 110901 involves complex and costly implementations since it must adapt to the defects identified specifically for each glazing unit.Such a solution cannot therefore be exploited on a large scale.

[0011]

[0012] The present invention aims to remedy all or part of the drawbacks of the prior art, in particular those set out above, by proposing a solution which makes it possible to identify and quantify with precision optical defects introduced by a plurality of glazings corresponding to the same vehicle glazing model.

[0013] The solution proposed by the invention is furthermore advantageous in that it makes it possible to eliminate (compensate, cancel) the optical defects identified on a large scale (i.e. for entire ranges of glazing), and is less complex to implement from a material point of view, and therefore also less expensive, than the solutions of the state of the art.

[0014] To this end, and according to a first aspect, the invention relates to a method for determining the optical quality of a plurality of glazings intended to equip vehicles and corresponding to the same model. Said method comprises, for the same determined zone of each of said glazings, steps of: - obtaining at least one optical aberration map, - for each optical aberration map, determining an amplitude of the associated optical aberration. Said method further comprises steps of: - for each optical aberration, determining an average amplitude from the amplitudes respectively determined for said optical aberration and for each of said glazings, - selecting, from the determined average amplitudes, optical aberrations satisfying a determined selection criterion.

[0015] The method according to the invention is therefore advantageous in that it is adapted to the glazing model given that the optical aberrations are selected from statistics carried out on a sample of glazing produced on the basis of this model.

[0016] In other words, the method according to the invention makes it possible to identify and quantify with precision optical defects introduced by a plurality of glazings from the same model. In this way, the method offers the possibility of designing an optical system capable of eliminating (compensating, canceling) the optical defects identified on a large scale (i.e. for the entire range of glazings). In this sense, the method according to the invention avoids having to design a dedicated optical system for each glazing considered in isolation.

[0017] This solution is therefore less complex to implement from a hardware point of view, and represents a fortiori a less expensive solution than those of the state of the art.

[0018] In particular embodiments, the method for determining optical quality may further comprise one or more of the following characteristics, taken individually or in all technically possible combinations.

[0019] In particular embodiments, each optical aberration map is determined from a wavefront error map itself determined at a given distance from the glazing, said distance being zero or strictly positive.

[0020] In particular embodiments, at least one of the optical aberration maps is chosen from the following list: - an X-tilt map, - a Y-tilt map, - a focus error map, - an astigmatism map oriented at 0°, - an astigmatism map oriented at 45°, - an X-coma map, - a Y-coma map, - a spherical aberration map, - a triangular astigmatism map oriented at 0°, - a triangular astigmatism map oriented at 30°, - a fifth-order astigmatism map oriented at 0°, - a fifth-order astigmatism map oriented at 45°.

[0021] In particular embodiments, the selection criterion is satisfied by an optical aberration if the average amplitude associated with said optical aberration is greater than a determined threshold.

[0022] In particular embodiments, the method further comprises a step of obtaining an evaluation of an optical quality indicator of all of said zones, called "global indicator", the selection criterion being satisfied by an optical aberration if its removal leads to reducing the difference between said evaluation and a target evaluation.

[0023] In particular embodiments, the selection step comprises the following sub-steps:- determination of an optical aberration whose average amplitude is maximum among the respective average amplitudes of the optical aberrations,- updating of the evaluation of the global indicator by numerical simulation, said numerical simulation being implemented by considering the hypothesis according to which said optical aberration of maximum amplitude is eliminated, said sub-steps being executed iteratively by excluding, during a current iteration, the optical aberration whose average amplitude was determined as being maximum during the previous iteration, and as long as the difference between the current evaluation of the global indicator and the target evaluation is greater than a given threshold, the optical aberrations eliminated by numerical simulation are those satisfying the selection criterion.

[0024] In particular modes of implementation, the global indicator is chosen from the following list: - a wavefront slope, - an optical power, - a point spread function, - a modulation transfer function, - a vertical distortion, - a horizontal distortion.

[0025] In particular embodiments, the glazing model is a windshield or a rear window or a side window.

[0026] According to a second aspect, the invention relates to a system for determining the optical quality of a plurality of glazings corresponding to the same glazing model intended to separate the interior and exterior environments of a vehicle, said system comprising means configured to implement a method for determining the optical quality according to the invention.

[0027] According to a third aspect, the invention relates to a method for manufacturing an optical system intended to be arranged in an interior environment of a vehicle, said system being configured to suppress one or more optical aberrations selected according to a method for determining the optical quality in accordance with the invention, the suppression(s) being carried out using the average amplitudes respectively determined for said selected optical aberration(s).

[0028] According to a fourth aspect, the invention relates to an optical system intended to be arranged in an interior environment of a vehicle, in particular intended to be arranged further inside than an outer face of a vehicle glazing, said system being configured to suppress one or more optical aberrations selected according to a method for determining the optical quality in accordance with the invention, the suppression(s) being carried out using the mean amplitudes respectively determined for said selected optical aberration(s).

[0029] According to a fifth aspect, the invention relates to vehicle glazing equipped with an optical system according to the invention.

[0030] According to a sixth aspect, the invention relates to a driving assistance system comprising an optical system according to the invention.

[0031] According to a seventh aspect, the invention relates to a vehicle comprising glazing according to the invention or a driving assistance system according to the invention.

[0032] According to an eighth aspect, the invention relates to a computer program comprising instructions for implementing steps of a method for determining optical quality according to the invention when said computer program is executed by a computer.

[0033] This program may use any programming language, and may be in the form of source code, object code, or code intermediate between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0034] According to a ninth aspect, the invention relates to a computer-readable information or recording medium on which a computer program according to the invention is recorded.

[0035] The information or recording medium may be any entity or device capable of storing the program. For example, the medium may include a storage medium, such as a ROM, for example a CD ROM or a microelectronic circuit ROM, or a magnetic recording medium, for example a hard disk.

[0036] On the other hand, the information or recording medium may be a transmissible medium such as an electrical or optical signal, which may be conveyed via an electrical or optical cable, by radio or by other means. The program according to the invention may in particular be downloaded from a network such as the Internet.

[0037] Alternatively, the information or recording medium may be an integrated circuit in which the program is incorporated, the circuit being adapted to carry out or to be used in carrying out the method in question.

[0038]

[0039] Other characteristics and advantages of the present invention will emerge from the description given below, with reference to the appended drawings which illustrate an exemplary embodiment thereof without any limiting character. In the figures:

[0040] schematically represents an example of a car windshield 10 according to a known embodiment of the state of the art;

[0041] schematically represents a system for determining the optical quality of a plurality of windshields according to a particular embodiment of the invention;

[0042] schematically represents an example of hardware architecture of a processing device belonging to the system of the;

[0043] la represents, in the form of a flowchart, a particular mode of implementation of a method for determining optical quality according to the invention, as executed by the system of the;

[0044] schematically represents, in the form of a flowchart, a first more specific example of implementation of the method for determining the optical quality of the;

[0045] schematically represents, in the form of a flowchart, a second, more specific example of implementation of the method for determining the optical quality of the.

[0046]

[0047] Description of embodiments

[0048] The invention relates in particular to the determination of the optical quality of a plurality of glazings corresponding to the same glazing model intended to separate the interior and exterior environments of a vehicle.

[0049] "Glazing" means a sheet formed from a transparent material. For example, the transparent material may be mineral glass, such as soda-lime, aluminosilicate, or borosilicate glass. Alternatively, the transparent material may be organic glass, such as stretched polymethyl methacrylate (stretched PMMA), unstretched polymethyl methacrylate, polycarbonate (PC), polyethylene terephthalate (PET), or polyurethane (PU).

[0050] For the remainder of the description, it is considered in no way limiting that the glazing model is a car windshield.

[0051] However, considering such a glazing model only constitutes a variant implementation of the invention, and nothing excludes considering other variants, such as for example a rear window or even a side window of said car.

[0052] Furthermore, the invention is not further limited by the fact of considering a car window. Thus, the invention applies equally to any type of transport vehicle, whether it is a road vehicle (e.g. car, truck, bus, etc.) or even a rail vehicle.

[0053] The glazing model is therefore here mass-produced, typically within a factory, and the invention therefore aims to determine the optical quality of all the glazings mass-produced on the basis of said model, so as to offer the possibility of eliminating (compensating, cancelling) any optical defects for the entire range, and not by considering the glazings one by one separately.

[0054] The diagram shows a schematic example of a car windshield 10 according to a known embodiment of the state of the art.

[0055] As illustrated by the, the windshield 10 comprises a sheet of glass 11 and an opaque element 12. The opaque element 12 makes it possible in particular to hide from the outside of the car elements arranged inside said car, for example a part of an image acquisition device.

[0056] By placing oneself at a distance from the windshield 10, it is observed that the opaque element 12 borders the windshield 10 along its entire periphery. To do this, the opaque element 12 can for example cover only one of the main faces of the glass sheet 11 (e.g. the main face intended to be oriented towards the interior of the car or the one intended to be oriented towards the exterior of the car). Alternatively, the opaque element 12 can comprise several portions, each of the portions being arranged on one or other of the main faces of the glass sheet 11.

[0057] It should be noted that in the case of multiple glazing comprising several sheets of glass, such as laminated glazing, the opaque element 12 can also be formed of several portions, each portion being arranged on the surface of two or more sheets of glass depending on the number of portions.

[0058] Preferably, the opaque element 12 is a layer of enamel deposited on the surface of the sheet 11. Naturally, the layer of enamel can be replaced by any other opaque element which makes it possible to hide from the outside certain elements arranged inside the car. The opaque element can also be a layer on a lamination interlayer or an opaque insert linked to such a lamination interlayer.

[0059] Generally speaking, the person skilled in the art knows how to produce an opaque element of glazing, so these aspects are not detailed further here.

[0060] The glass sheet 11 is intended to be integrated into a car (not shown in the figures) with an angle of inclination. No limitation is attached to the value of this angle of inclination, which may for example be substantially equal to 30°. Furthermore, the glass sheet 11 may be curved along one or two axes, no limitation being attached to the respective radii of curvature of these axes.

[0061] As illustrated by the in no way limiting, the opaque element 12 delimits a determined zone 13 of the glass sheet 11, and therefore a fortiori of the windshield 10. This zone 13 is, in this example, located at the level of the upper edge of the windshield 10. The zone 13 is intended to be placed on the optical path of an image acquisition device making it possible to obtain a 2D or 3D representation of a volume outside the vehicle, such as a camera of an intelligent driving assistance system, for example a high-resolution digital camera adapted to operate in the visible, i.e. in wavelengths between 390nm and 750nm.

[0062] No limitation is attached to the surface area of ​​the zone 13, which may for example be substantially equal to 0.5m2. Furthermore, considering a location of the zone 13 at the upper edge of the windshield 10 constitutes only a variant implementation of the invention, and nothing excludes considering another location as long as the zone in question is on the optical path of an image acquisition device.

[0063] Schematically represents a system 100 for determining the optical quality of a plurality of windshields 10_1,…,10_N according to a particular embodiment of the invention.

[0064] More specifically, the aim here is to determine the optical quality of each of the zones 13_1,…,13_N of each of said windshields 10_1,…,10_N, these zones 13_1,…,13_N being, as already mentioned above, intended to be in the field of vision (i.e. on the optical path) of a suitable image acquisition device when each of the windshields 10_1,…,10_N is integrated into a car.

[0065] The system 100 is therefore configured so as to allow the calculation of statistics relating to the presence of optical defects in a zone 13 of the windshield model 10, on the basis of defects measured and quantified in each of the zones 13_1,…,13_N of each of said windshields 10_1,…,10_N. The objective being, ultimately and on the basis of such statistics, to design an optical system capable of eliminating the optical defects detected for this plurality of windshields 10_1,…,10_N.

[0066] As far as a plurality of windshields 10_1,…,10_N are considered, the number N is greater than or equal to 2. That being said, no limitation is attached to the value of said number N. Generally speaking, the larger the number N, the more precise the calculated statistics are.

[0067] It should be noted that the represents a frozen situation in which a single windshield 10_i appears in a top view (i being therefore an integer index fixed between 1 and N). It is nevertheless understood that this representation is made for illustrative purposes only and with a view to simplifying the description of the invention, it being understood that each of the windshields 10_1,…,10_N is intended to be analyzed by the system 100 with a view to determining its optical quality.

[0068] In the embodiment described herein, the system 100 comprises a light emitting device 110 and a processing device 120.

[0069] In order to determine the optical quality thereof, the windshield 10_i is positioned between the emitting device 110 and the processing device 120. More particularly, this positioning is carried out so that the emitting device 110 is located on the external face side of the windshield 10_i (i.e. on the side intended to be part of the environment outside the car), the processing device 120 being located on the internal face side of said windshield 10_i (i.e. on the side intended to be part of the environment inside the car).

[0070] By way of non-limiting example, the windshield 10_i is positioned at a distance of between 200mm and 250mm from the emitting device 110 and at a distance of between 250mm and 300mm from the processing device 120.

[0071] The emitting device 110 is configured to emit a beam of light rays (dotted arrows on the) through the given area 13_i of the windshield 10_i. To do this, the emitting device 110 comprises a light source, for example monochromatic, and a collimator placed after the light source in order to obtain a beam of light rays, for example parallel light rays.

[0072] Furthermore, the light source of the emitting device 110 is adapted to emit in the visible, that is to say in the wavelengths between 390nm and 750nm, preferably between 640nm and 660nm, or even to emit in the near infrared, such as for example at 905nm or 1550nm.

[0073] Advantageously, the size of the light beam makes it possible to cover the entire given area 13_i of the windshield 10_i while guaranteeing sufficient resolution and a flow making it possible to obtain information in the entire given area 13_i. For example, the size of the beam may cover an area larger than the area 13_i. However, nothing precludes considering that the size of the light beam is substantially identical to that of the area 13_i, or possibly even smaller than it.

[0074] The processing device 120, for its part, is configured to control the emitting device 110 (i.e. to control its operation by activating / deactivating it) as well as to carry out, from the light rays which reach it after having passed through the zone 13_i of the windshield 10_i, processing operations aimed at identifying and quantifying optical aberrations produced by said zone 13_i, by implementing a method for determining optical quality according to the invention.

[0075] Considering a control (via appropriate commands) of the transmitter device 110 by the processing device 120 constitutes only one variant of implementation of the invention. Other variants are conceivable, such as for example a control of the transmitter device 110 by a device other than the processing device 120, this other device being integrated or not into the system 100. Nothing also excludes the possibility of considering a manual control of the transmitter device 110 by an operator.

[0076] Generally, the system 100 is described in the present embodiment as being formed by only the emitting device 110 and processing device 120. However, nothing precludes considering other embodiments in which the system 100 still comprises other elements, such as for example: - means configured to hold a windshield in position between said emitting device 110 and processing device 120 (robotic mechanical arm, etc.), and / or - means configured to bring the windshields in turn to the level of said emitting device 110 and processing device 120 (conveyor, etc.), and / or - a mirror arranged on the side of the internal face of the windshield 10_i to return the light rays towards the emitting device 110, the latter integrating the processing device 120.

[0077] For further details / alternative embodiments relating to the hardware and / or software aspects of the configuration of the system 100, particularly with regard to the transmission of a light beam, it is possible to refer to the document WO 2021 / 110901 already mentioned previously.

[0078] Schematically represents an example of hardware architecture of the processing device 120 according to the invention.

[0079] As illustrated by the, the processing device 120 has the hardware architecture of a computer. Thus, the processing device 120 comprises, in particular, a processor 120_1, a random access memory 120_2, a read only memory 120_3 and a non-volatile memory 120_4. It also has communication means 120_5.

[0080] The read-only memory 120_3 of the processing device 120 constitutes a recording medium in accordance with the invention, readable by the processor 120_1 and on which is recorded a computer program PROG in accordance with the invention, comprising instructions for executing steps of the method for determining optical quality according to the invention. The program PROG defines functional modules of the processing device 120, which rely on or control the hardware elements 120_1 to 120_5 of the processing device 120 cited above. These functional modules are illustrated in the figure without any limitation being implied, and are described in more detail below with reference to particular modes of implementation of the method for determining optical quality.

[0081] The communication means 120_5 allow in particular the processing device 120 to transmit commands to the transmitting device 110. These communication means 120_5 rely, in a manner known per se, on a communication interface capable of exchanging data between the processing device 120 and the transmitting device 110. No limitation is attached to the nature of this communication interface, which can be wired or wireless, so as to allow the exchange of data according to any protocol known to those skilled in the art (Ethernet, Wifi, Bluetooth, 3G, 4G, 5G, Modbus, TCP-IP, analog, etc.).

[0082] La represents, in the form of a flowchart, a particular mode of implementation of the method for determining the optical quality according to the invention, as executed by the system 100 of the.

[0083] The method for determining the optical quality firstly comprises a first phase in which a set of steps is implemented iteratively for each of the zones 13_1,…,13_N of each of said windshields 10_1,…,10_N.

[0084] We will now describe an implementation (i.e. an iteration) of said set of steps of the first phase, considering a given windshield 10_i (and therefore a fortiori a given zone 13_i). As illustrated by the, said set of steps comprises a step E10_i of obtaining a plurality of optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M all associated with the zone 13_i (M being an integer index strictly greater than 1).

[0085] More particularly, in the present embodiment, said obtaining step E10_i comprises a plurality of sub-steps, including a sub-step E10_i_1 of generating a command COM_i for activating the light beam of the emitting device 110 (so as to illuminate the zone 13_i). Said sub-step E10_i_1 is implemented by a control module MOD_COM equipping the processing device 120.

[0086] Step E10_i also includes a sub-step E10_i_2 of transmitting the command COM_i to the transmitting device 110. Said sub-step E10_i_2 is implemented by a transmission module MOD_TX equipping the processing device 120 and integrated into the communication means 120_5.

[0087] Step E10_i also includes a sub-step E10_i_3 of emitting the light beam F_LUM through the zone 13_i (from the outside to the inside of the windshield 10_i), by the emitting device 110, upon receipt of the command COM_i.

[0088] Step E10_i also comprises a sub-step E10_i_4 of analyzing the light rays transmitted by the zone 13_i, so as to determine, on the inner face side of the windshield 10_i and at a given distance D_i from the windshield 10_i, a wavefront error map C{ERR}_i. Said sub-step E10_i_4 is implemented by an analysis module MOD_ANA equipping the processing device 120.

[0089] In other words, with regard to the implementation of said sub-step E10_i_4, it is understood that the processing device 120 is notably configured to measure the shape of the wavefront of the beam emitted by the emitting device 110 and to determine the deformation undergone by the wavefront during its passage through the zone 13_i.

[0090] As a reminder, a wavefront corresponds to the three-dimensional wave surface defined so that each light ray coming from the same light source is orthogonal to it. Consequently, the processing device 120 is configured to measure (determine) the shape of this wave surface.

[0091] The processing device 120 may, for example, comprise a system based on four-wave interferometry (with lateral shift). A system is also known under the trade name “Phasics-SID4-HR”.

[0092] Generally speaking, no limitation is attached to the hardware and / or software configuration of the processing device 120 with regard to the measurement of the shape of the wavefront, and therefore the determination of the wavefront error map C{ERR}_i from this measurement.

[0093] Moreover, the implementation of sub-step E10_i_4 is also not limited by the value of the distance D_i at which the map C{ERR}_i is determined on the inside of the windshield 10_i. Thus, said distance D_i may be zero or strictly positive, for example between 0 mm and 1500 mm. In particular, the processing device 120 may be configured to determine the shape of the wavefront at a first given distance distinct from the distance D_i, and furthermore comprise means configured in hardware and software to extrapolate (for example by digital simulation) said shape of the wavefront at said distance D_i.

[0094] Step E10_i also comprises a sub-step E10_i_5 for determining the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M from the wavefront error map C{ERR}_i. Said sub-step E10_i_5 is implemented by a first determination module MOD_DET_1 equipping the processing device 120.

[0095] The determination of the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M from the wavefront error map C{ERR}_i can be implemented according to any technique known to those skilled in the art. For example, such a technique may belong to the field of image processing, and concern for example a decomposition (projection) of the wavefront error map C{ERR}_i onto a basis of polynomial functions. Advantageously, said basis of polynomial functions corresponds to the Zernike polynomials which are known to be particularly suitable for the decomposition of complex surfaces, in particular on a disk, into a sum of elementary surfaces which each correspond (univocal correspondence) to a particular degree and type of optical aberration. However, we understand that nothing excludes considering another polynomial basis, taking into account for example more particularly the form of the zone 13_i (egLegendre polynomials in the case of a rectangular 13_i area).

[0096] Furthermore, no limitation is attached to the value of the number M, it being understood, of course, that the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M are distinct two by two. For example, at least one of the optical aberration maps is chosen from the following list:- an X-tilt map,- a Y-tilt map,- a focus error map,- an astigmatism map oriented at 0°,- an astigmatism map oriented at 45°,- an X-coma map,- a Y-coma map,- a spherical aberration map,- a triangular astigmatism map oriented at 0°,- a triangular astigmatism map oriented at 30°,- a fifth-order astigmatism map oriented at 0°,- a fifth-order astigmatism map oriented at 45°.

[0097] It is further noted that the method is described here considering that a plurality of optical aberration maps are determined from the wavefront error map C{ERR}_i. This is not, however, a limitation of the invention, and nothing precludes considering that only one optical aberration map is determined.

[0098] For further details / alternative embodiments relating to the hardware and / or software aspects of the configuration of the system 100, particularly with regard to the determination of a wavefront error map and the determination of optical aberration maps, reference may be made to the document WO 2021 / 110901 already mentioned above.

[0099] As illustrated by the, said set of steps of the first phase also comprises a step E20_i of determining respective amplitudes AMP_i_1,…,AMP_i_M of said optical aberrations from the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M. Said step E20_i is implemented by a second determination module MOD_DET_2 equipping the processing device 120.

[0100] By way of non-limiting example, when the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M are determined using the basis of the Zernike polynomials, the amplitudes AMP_i_1,…,AMP_i_M correspond to the values ​​of the coefficients of the decomposition on said basis, these values ​​being typically expressed as a fraction of the wavelength at which the illumination of the zone 13_i is carried out.

[0101] Of course, nothing excludes determining the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M using a basis other than the Zernike basis. In this case, the amplitudes AMP_i_1,…,AMP_i_M may correspond to the values ​​of the coefficients of the decomposition on the said other basis if there is a one-to-one correspondence between the functions of the said other basis and the optical aberrations considered, or to combinations of values ​​of such coefficients if the correspondence between the functions of the said other basis and the optical aberrations considered results from combinations of these other basis functions.

[0102] Said set of steps E10_i, E20_i has been described so far by considering a windshield 10_i among said plurality of windshields 10_1,…,10_N. That being said, and as already mentioned, said set of steps E10_i, E20_i is iterated for each of said windshields 10_1,…,10_N, these iterations being carried out by considering the same zones 13_1,…,13_N (in terms of location on the windshields 10_1,…,10_N), the same distances D_1,…,D_N and as well as the same optical aberrations to be determined (via said optical aberration maps).

[0103] The method for determining optical quality then includes a second phase aimed at producing statistics from the amplitudes AMP_i_1,…,AMP_i_M (i covering all the integers between 1 and N) obtained during the first phase as well as producing a selection of optical aberrations according to a determined selection criterion.

[0104] More particularly, in the present embodiment, the method comprises a step E30 of determining, for each of the optical aberrations considered during the first phase (via said optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M), an average amplitude from the amplitudes respectively determined for said optical aberration and for each of said windshields 10_1,…,10_N. Said step E30 is implemented by a third determination module MOD_DET_3 equipping the processing device 120.

[0105] In other words, for an integer index j fixed between 1 and M and thanks to the processing of the first phase, we consider an optical aberration associated with the maps C{ABB}_1_j,…,C{ABB}_N_j, and therefore a fortiori with the amplitudes AMP_1_j,…,AMP_N_j. Said step 30 then consists of calculating the amplitude AMP_AVE_j corresponding to the arithmetic mean of the amplitudes AMP_1_j,…,AMP_N_j.

[0106] Finally, at the end of step E30, we obtain M average amplitudes AMP_AVE_1,…,AMP_AVE_M respectively associated with the optical aberrations considered during the first phase.

[0107] Therefore, and as illustrated by the, the method comprises a step E40 of selection, from the average amplitudes AMP_AVE_1,…,AMP_AVE_M, of optical aberrations satisfying a determined selection criterion CRIT. Said step E40 is implemented by a selection module MOD_SELECT equipping the processing device 120.

[0108] It is noted that the method for determining the optical quality has been described up to now by considering that the step E10_i of obtaining a plurality of optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M comprises the implementation of the sub-steps E10_i_1,…,E10_i_5. These provisions are however not limiting of the invention. Indeed, the term “obtaining” with regard to step E10_i can still refer to the fact of receiving the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M, it being understood that these optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M have been determined prior to the execution of the method for determining the optical quality and for example stored in appropriate storage means (e.g. dedicated server). The reception of the cards C{ABB}_i_1,…,C{ABB}_i_M is carried out for example on request transmitted by the processing device 120.

[0109] According to yet another alternative, the optical aberration maps C{ABB}_i_1,…,C{ABB}_i_M have been determined prior to the execution of the method for determining the optical quality, as well as received and stored by the processing device 120, for example in its non-volatile memory 120_4. Therefore, the term “obtaining” with regard to step E10_i refers here to the fact of accessing (loading) the maps C{ABB}_i_1,…,C{ABB}_i_M thus stored.

[0110] Schematically represents, in the form of a flowchart, a first particular example of implementation of the method for determining optical quality, in which the selection criterion CRIT is satisfied by an optical aberration if the average amplitude associated with said optical aberration is greater than a given threshold.

[0111] In said first example, and as illustrated by the, the selection step E40 comprises: - a sub-step E40_1_1 for comparing each of the amplitudes AMP_AVE_1,…,AMP_AVE_M with a threshold. This threshold may for example be identical for all the amplitudes AMP_AVE_1,…,AMP_AVE_M, for example equal to 1 x 10 -4 λ, where λ corresponds to the wavelength at which the illumination of the zones 13_1,…,13_N is carried out. Alternatively, nothing excludes considering distinct thresholds for one or more subsets of amplitudes among the amplitudes AMP_AVE_1,…,AMP_AVE_M (it being understood that a subset may contain a single element), - a sub-step E40_1_2 of selection of one or more optical aberrations according to the results of the comparison sub-step E40_1_1.

[0112] The implementation of such a first example makes it possible to select one or more optical aberrations of which it is evaluated (via comparison with a threshold) that their respective amplitudes are sufficiently large among all the windshields 10_1,…,10_N of the same range, so that it is decided to eliminate them (compensate, cancel) as is described in more detail later.

[0113] Schematically represents, in the form of a flowchart, a second particular example of implementation of the method for determining optical quality, in which the selection of one or more optical aberrations is carried out with the aim of reducing the gap between an evaluation of an optical quality indicator of the set of zones 13_1,…,13_N and a target evaluation.

[0114] Therefore, in said second example of implementation, and as illustrated in no way limiting by the, said method comprises, during the first phase and for each zone 13_i, a step E15_i of obtaining an evaluation EVAL_IND_i of an optical quality indicator IND_i.

[0115] In other words, we consider an optical quality indicator of the same nature for each of the zones 13_1,…,13_N, and we seek to quantify it using processes known to those skilled in the art to provide an evaluation, such as for example from the wavefront error maps C{ERR}_1,…, C{ERR}_N.

[0116] As a non-limiting example, the optical quality indicator IND_i is chosen from the following list: - a wavefront slope, - an optical power, - a point spread function, - a modulation transfer function, - a vertical distortion, - a horizontal distortion.

[0117] It is noted that no limitation is attached to the form taken by said optical quality indicator IND_i. Thus, it can be in the form of a point value, a map, a function, etc.

[0118] Furthermore, obtaining the evaluation EVAL_IND_i of the optical quality indicator IND_i of each zone 13_i can be done using any technique known to those skilled in the art. It can also involve transmitting said evaluation EVAL_IND_i, it being understood that it has been determined prior to the implementation of the method and stored in appropriate storage means (example: dedicated server).

[0119] In said second example of implementation of the, the method also comprises a step E35 of obtaining an evaluation of an optical quality indicator EVAL_IND_AVE for all of the zones 13_1,…,13_N, also called “global indicator IND_AVE”.

[0120] Concretely, in this example, said evaluation EVAL_IND_AVE corresponds to the average of the evaluations of indicators EVAL_IND_1,…,EVAL_IND_N respectively determined for each of the windshields 10_1,…,10_N during the iterations of steps E15_i.

[0121] Therefore, once said evaluation EVAL_IND_AVE has been determined, the selection step E40 is implemented by considering that the selection criterion CRIT is satisfied by an optical aberration if its removal leads to a reduction in the gap DELTA_IND between said evaluation EVAL_IND_AVE and a target evaluation EVAL_IND_T.

[0122] More specifically, and as illustrated by the, the selection step E40 comprises the following sub-steps: - a sub-step E40_2_1 for determining an optical aberration whose average amplitude is maximum among the respective average amplitudes AMP_AVE_1,…,AMP_AVE_M of the optical aberrations, - a sub-step E40_2_2 for updating the evaluation EVAL_IND_AVE of the global indicator IND_AVE by numerical simulation, said numerical simulation being implemented by considering the hypothesis according to which said optical aberration of maximum amplitude is eliminated.

[0123] Furthermore, said sub-steps E40_2_1, E40_2_2 are executed iteratively by excluding, during a current iteration, the optical aberration whose average amplitude was determined to be maximum during the previous iteration, and as long as the difference DELTA_IND between the current evaluation of the global indicator IND_AVE and the target evaluation EVAL_IND_T is greater than a given threshold.

[0124] Ultimately, the optical aberrations removed by numerical simulation to reduce the average amplitude AMP_AVE_DOPT below the threshold are those satisfying the CRIT selection criterion.

[0125] It is important to note, however, that the selection of optical aberrations in accordance with said second example of lane constitutes only one variant of implementation of the invention. Also, nothing excludes the possibility of considering other variants, such as, for example, carrying out a selection of optical aberrations in order to reduce said DELTA_IND difference from a predetermined list of optical aberrations, this selection being carried out while respecting the order in which the optical aberrations are classified within said list.

[0126] In addition or as an alternative, it is possible to consider that the evaluation EVAL_IND_AVE of the global indicator IND_AVE is not calculated but is the subject of a transmission to the processing device 120, it being understood that said evaluation EVAL_IND_AVE was determined prior to the execution of the method and stored in appropriate storage means (example: dedicated server). It is understood that in this case, the steps E15_i are not implemented.

[0127] It should be noted that the method for determining the optical quality has been described up to now by considering that each of the windshields 10_1,…,10_N is already in position with respect to the emitting devices 110 and processing devices 120. That being said, it is possible to envisage other modes of implementation in which the method comprises additional steps of positioning the windshields 10_1,…,10_N and / or of positioning the emitting devices 110 and processing devices 120.

[0128] Ultimately, by thus evaluating the optical quality of the windshields 10_1,…,10_N, it is possible to detect (measure, identify) and quantify optical aberrations which each affect the zones 13_1,…,13_N. Therefore, and according to another aspect, the invention also relates to an optical system and its manufacturing method, said optical system being intended to be arranged in an interior environment of a vehicle, and being further configured to suppress (compensate, cancel) one or more of the optical aberrations selected during step E40 of the method for determining the optical quality, the suppression(s) being carried out using the mean amplitudes respectively determined for said selected optical aberration(s).

[0129] In other words, by being placed between a zone 13_i of a windshield 10_i and an image acquisition device, such an optical system advantageously makes it possible to correct the images intended to be acquired by said image acquisition device.

[0130] The production of such an optical system, once the average amplitudes of the optical aberrations to be eliminated are known, is known to those skilled in the art. In particular, such an optical system may comprise one or more suitable lenses, one or more suitable collimators, etc. so that the wavefront takes on a shape which opposes the selected aberrations.

[0131] It is understood that such an optical system is particularly advantageous in that it is suitable for the windshield model 10, given that the optical aberrations are selected on the basis of average amplitudes. In other words, said optical system of the invention makes it possible to eliminate (compensate, cancel) the optical defects identified on a large scale (i.e. for the entire range of windshields). In this sense, the optical system according to the invention avoids having to design a dedicated optical system for each windshield considered in isolation, and is therefore less complex to implement from a hardware point of view, and a fortiori represents a less expensive solution than those of the state of the art.

[0132] It should be noted that the optical system of the invention can be arranged directly on a windshield (on its internal face), for example by means of a plate. Alternatively, the optical system of the invention can be arranged at a distance from a windshield, in the interior environment of a vehicle. For these reasons, and according to other aspects, the invention also relates to:- vehicle glazing equipped with said optical system,- a driving assistance system comprising said optical system,- a vehicle comprising such glazing or such a driving assistance system.

Claims

Method for determining the optical quality of a plurality of glazings intended to equip vehicles and corresponding to the same model, the method comprising, for the same determined zone of each of said glazings, steps of: - obtaining (E10_i) at least one optical aberration map, - for each optical aberration map, determining (E20_i) an amplitude of the associated optical aberration, the method further comprising steps of: - for each optical aberration, determining (E30) an average amplitude from the amplitudes respectively determined for said optical aberration and for each of said glazings, - selecting (E40), from the determined average amplitudes, optical aberrations satisfying a determined selection criterion. Method according to claim 1, in which each optical aberration map is determined from a wavefront error map itself determined at a given distance from the glazing, said distance being zero or strictly positive. Method according to any one of claims 1 to 2, wherein at least one of the optical aberration maps is chosen from the following list:- an X-tilt map,- a Y-tilt map,- a focus error map,- an astigmatism map oriented at 0°,- an astigmatism map oriented at 45°,- an X-coma map,- a Y-coma map,- a spherical aberration map,- a triangular astigmatism map oriented at 0°,- a triangular astigmatism map oriented at 30°,- a fifth-order astigmatism map oriented at 0°,- a fifth-order astigmatism map oriented at 45°. Method according to any one of claims 1 to 3, in which the selection criterion is satisfied by an optical aberration if the average amplitude associated with said optical aberration is greater than a determined threshold (E40_1_1, E40_1_2). Method according to any one of claims 1 to 4, said method further comprising a step of obtaining (E35) an evaluation of an optical quality indicator of all of said zones, called "global indicator", the selection criterion being satisfied by an optical aberration if its removal leads to a reduction in the difference between said evaluation of the global indicator and a target evaluation. Method according to claim 5, in which the selection step comprises the following sub-steps:- determination (E40_2_1) of an optical aberration whose average amplitude is maximum among the respective average amplitudes of the optical aberrations,- updating (E40_2_2) of the evaluation of the global indicator by numerical simulation, said numerical simulation being implemented by considering the hypothesis according to which said optical aberration of maximum amplitude is eliminated, said sub-steps being executed iteratively by excluding, during a current iteration, the optical aberration whose average amplitude was determined as being maximum during the previous iteration, and as long as the difference between the current evaluation of the global indicator and the target evaluation is greater than a given threshold, the optical aberrations eliminated by numerical simulation are those satisfying the selection criterion. Method according to any one of claims 5 to 6, in which the global indicator is chosen from the following list:- a wavefront slope,- an optical power,- a point spread function,- a modulation transfer function,- a vertical distortion,- a horizontal distortion. A method according to any one of claims 1 to 7, wherein the glazing pattern is a windshield or a rear window or a side window. System (100) for determining the optical quality of a plurality of glazings corresponding to the same glazing model intended to separate the interior and exterior environments of a vehicle, said system comprising means (110, 120) configured to implement a method according to any one of claims 1 to 8. A method of manufacturing an optical system intended to be arranged in an interior environment of a vehicle, said system being configured to suppress one or more selected optical aberrations according to a method according to any one of claims 1 to 8, the suppression(s) being carried out using the mean amplitudes respectively determined for said selected optical aberration(s). An optical system for arrangement in an interior environment of a vehicle, said system being configured to suppress one or more selected optical aberrations according to a method according to any one of claims 1 to 8, the suppression(s) being carried out using the mean amplitudes respectively determined for said selected optical aberration(s). Vehicle glazing equipped with an optical system according to claim 11. Driving assistance system comprising an optical system according to claim 11. Vehicle comprising glazing according to claim 12 or a driving assistance system according to claim 13.

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