EP4085284A1

EP4085284A1 - Device with glazing and associated thermal camera, and optimization methods

Info

Publication number: EP4085284A1
Application number: EP20851227.7A
Authority: EP
Inventors: Mathieu Berard; Keihann Yavari
Original assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Current assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Priority date: 2020-01-03
Filing date: 2020-12-23
Publication date: 2022-11-09
Also published as: CN113382857A; FR3105944B1; CN113382857B; FR3105944A1; US20230074901A1; WO2021136909A1; US11962933B2

Abstract

The invention relates to a device comprising a vehicle glazing (100) that includes, in a peripheral region, a through-hole having an insert (2), and comprising a thermal camera. The invention also relates to a method for optimizing said device.

Description

DESCRIPTION

TITLE: DEVICE WITH GLASS AND ASSOCIATED THERMAL CAMERA AND OPTIMIZATION PROCESSES

The invention relates to a device combining glazing, in particular a windshield, in a motor vehicle, train or airplane, and said thermal camera for such viewing of information on a glazing.

Vehicle glazing and associated technology are constantly evolving, in particular to improve safety.

In particular, patent GB2271139 proposes a windshield comprising a laminated glazing with, in a central part and close to the upper longitudinal edge, an opening filled by an insert made of a material highly transparent to thermal infrared, more precisely zinc sulphide (ZnS) transmission of at least 50% from 5 to 15μm. A dedicated camera coupled to a screen visible to the driver is in the passenger compartment in front of the insert. The hole is circular and the insert is a disc glued to the walls of the hole.

In terms of manufacture, the hole is made before the windshield glass is autoclaved.

The object or person detection performance of such a device can be improved.

To this end, the present invention relates to a device which comprises:

- vehicle glazing (in particular laminated and / or curved), in particular automobile (car, truck, public transport: bus, coach, etc.) or rail (in particular at maximum speed of at most 90 km / h or at most 70km / h, in particular subways, tramways), in particular windshield, rear window, side glazing, of a given thickness E1 (subcentimetric in particular at most 5mm for an automobile windshield), glazing having a main face exterior (called F1) oriented towards the outside and a main (most) internal face on the passenger compartment side (called F4 if laminated glazing or called F2), glazing comprising, in a peripheral zone preferably in the upper part of the glazing (preferably in upper longitudinal edge in particular in a central region of the upper part), a through hole between the internal face and the external face, hole delimited by a side wall of the glazing, in particular through hole forming a peripheral notch or closed hole (surrounded by the wall ), in particular the hole of constant diameter or a larger diameter on the inner face than on the front outside), in particular of convex cross section in particular circular or oval or ellipsoidal or even rectangular, square or hexagonal

- in said through-hole, an insert (flat or curved, with an outer face F1, or also with an inner face protruding, F2 or respectively F4 if laminated glazing) made of transparent material in a range A of wavelengths in the spectrum infrared beyond 2.5μm, ranging at least from 9.5 to 10.5μm and preferably from 8 to 12μm, the insert being of given thickness e, in particular from 3 to 10mm, made of material of index of refraction n in the range A, in particular from 1.35 to 4.5 with an entry face facing the passenger compartment (flush with or set back from the internal face and an exit face (flush or set back from the external face), l 'insert, preferably being of circular or quasi-circular shape, the entry face being inscribed in a rectangle or square of width Wi and height Di with aspect ratio Di / Wi of at least 0.8 or 0.9 and at most 1.1 or 1, 2, preferably Di> Wi, with Di of at most 35mm, in particular of at least 5mm or 8mm, defining a center O which is the intersection diagonals of said rectangle,

a so-called thermal camera, arranged on the internal face side so as to receive electromagnetic radiation after passing through said insert, thermal camera comprising an entrance pupil, in particular circular, with a height p, (generally diameter) and an infrared detection system in the range A for example by microbolometry, in particular without cryogenic cooling and an objective, the camera being defined by:

- an optical axis X 'passing through the center C of the pupil, C facing the insert,

- a vertical viewing angle θ of at least 10 ° or 20 ° and in particular of at most 70 ° or 60 °.

The camera has a given volume defined by a contact point T (a corner / upper front plane of the lens / front or rear of the lens) capable of first touching the glazing, or a plate on the internal face of the lens. glazing, or the insert, or a part in the peripheral environment of said glazing, in the mounted position in a vehicle.

We define the orthogonal coordinate system (O, X, Y, Z) in which X is an axis parallel to the optical axis X, oriented towards the external face, Z the axis normal to the optical axis, the Y axis normal to X in the plane containing PO oriented towards the top of the glazing, Z normal to PO.

T being in a PO plane passing through O and C where we define Tv said virtual contact point being the projection of T in said PO plane, w being the distance along X and algebraically in the PO plane of T or Tv and h is the distance along Y in the plane PO between C and T or Tv. The entry face of the insert has an inclination defined by an angle α with respect to X.

We define a first line Dt1 [Math 1]

We define a second line Dt2 [Math 2]

Dt1 and Dt2 are secant in CO (xco, yco) with [Math 3]

[Math 4] sina

We define a third line Dt3 [Math 5] Dt1 and Dt3 are secant in

Dt2 and Dt3 are secant in

[Math 6]

[Math 7]

[Math 8]

[Math 9] x _c being a negative value, y _c a positive value, the camera being in contact by the point T or spaced apart.

In a case a), and is inside a triangle of vertices at at least 50% of the pupil being positioned in said triangle including E.

In a case b) when

[Math 10] so

We then define a point K of intersection between a straight line therefore

[Math 11]

[Math 12] e

[Math 13] or even [Math 14]

We have defined the center of the entrance pupil of the camera, that is to say the center of the diaphragm of the camera as seen from the outside. To optimize the position of the camera as much as possible in order to maximize the field of view, three constraints must be observed:

- a constraint to be respected so as not to reduce the vertical field of view downwards (optical constraint) - a constraint to be respected so as not to reduce the vertical field of view upwards (optical constraint)

- a constraint so that the lens does not hit the windshield (mechanical constraint). The limit case of each of these constraints defines the three lines Dt1, Dt2, Dt3 in the cases where the three constraints can be respected these three lines define a triangle in the vertical plane. We want the center of the camera pupil to be in this triangle.

On the horizontal, the inclination of the windshield has little effect and therefore does not affect the horizontal field of view. What is more, since the tilt of the windshield is on the vertical and not in the other direction, the camera is placed in the middle because symmetry on the left - right axis and therefore no optimization is required. Optimization is therefore only on vertical placement. yco is the result of optical and not mechanical constraints, its value is therefore independent of w and h

With f focal length of the camera, we have, with h _sensor, the height of the sensor and θ the vertical angle of view of the camera [Math 15]

Note that p is equal to f / N.

Preferred is infrared detection with maximum sensitivity in range A and even low sensitivity beyond 15 or 14μm and below 7 or 6μm.

As an example of a thermal camera, mention may be made of the product Atom®1024 from the company Lynred USA.

Advantageously:

- in case a) at least 70%, 80%, 90% or even 100% of the pupil is positioned in said triangle C0FE including E

- in case a)

- θ is at least 20 ° and in particular at most 50 °

- Di is at most 20mm

- w goes in absolute value from 1mm to 10cm

- h goes from 1mm to 2cm. In particular: yc <10mm and / or lxcl <5cm.

For case a):

- for co :

- for E:

- and for F:

For case b):

- yco goes from 1 mm to 3mm.

If we do not prefer not to tilt the camera too much in relation to the horizontal so we choose an X '(or X) inclined at most 30 °, 20 °, 10 °, 5 ° with the horizontal and / or at most an angle equal to θ / 2 ± 2 ° or ± 1 °.

The range A is from 9.5μm to 10.5μm, preferably 8 to 12μm or 13μm, preferably with a light transmission of at least 50% and better still of at least 60%, 65% or 70% in this beach A

And there is preferably between the insert and the side wall, means for fixing the insert (and also preferably sealing against liquid or even gaseous water), in particular in the form of a ring made of polymer material. organic (or inorganic organic hybrid) and / or flexible, for example polycarbonate.

According to the invention, furthermore, the material of the insert may be germanium or ZnS (conventional).

According to the invention, moreover, the material of the insert can be transparent in the visible at a reference wavelength between 500nm and 600nm and even from 540 or 550nm to 600nm, better in a range B of 550 to 600nm, preferably with a light transmission of at least 25% and better still at least 30% or more preferably 40%, 60% in range B.

Unlike conventional ZnS which is opaque in the visible spectrum, the material of the insert according to the invention can be transparent in the visible area, which allows:

- to identify faults in the crystal in a simple way, thus limiting the scrap rate

- to pre-aim the optical system (with a so-called thermal camera sensitive in the reference wavelength)

Light transmission is measured for the reference wavelength or better for range B with a spectrophotometer such as the Perkin Elmer Lambda-35. The light transmission can be measured according to the ISO 9050: 2003 standard using the illuminant D65, and be the total transmission (in particular integrated in the visible range and weighted by the sensitivity curve of the human eye), taking into account both of the direct transmission and of the possible diffuse transmission, the measurement being made for example using a spectrophotometer equipped with an integrating sphere, the measurement at a given thickness then being converted if necessary to the reference thickness of 4mm according to ISO 9050: 2003.

Infrared optical transmission is measured for range A by a Fourier spectrometer such as the BrukerVertex-70.

Advantageously, the material of the insert has:

- an infrared optical transmission of at least 50% and better still of at least 60%, 65% or 70% in the range A, in particular a variation of infrared optical transmission of at most 5% or 3% or 2% ( flat spectrum) in range A

- and a light transmission of at least 25% and better still of at least 30% or even 40%, 60% in range B, in particular a variation in light transmission of at most 5% or 2% (flat spectrum) in beach B.

The insert is, for example, colorless or tinted (while remaining transparent), in particular yellow, orange.

The insert material can be polished (outside and inside).

Advantageously, the material of the insert according to the invention is chosen from a material (preferably polycrystalline), in particular obtained by chemical vapor deposition) following:

- a zinc compound comprising selenium and / or sulfur or

- a compound comprising a barium fluoride

- Even a compound comprising thallium-iodide bromide such as that of KRS-5 type (Thallium Bromide-lodide).

And in particular the material of the insert is chosen from:

- a compound comprising a multispectral zinc sulphide, in particular obtained after hot isostatic pressing (treatment by an isostatic press at a temperature preferably of at least 800 ° C), in particular including selenium, such as ZnS _x Se ₁ - _x with x preferably at least 0.97 more preferably at least 0.99 and more preferably at least 0.998

- a compound comprising a zinc selenide, in particular ZnSe,

. a compound comprising a barium fluoride, in particular BaF ₂ . Zinc sulfide with multispectral grade (MS) is a recent material. It can be polycrystalline and obtained by implementing (in particular after formation by chemical vapor deposition CVD from zinc vapor and H ₂ S gas) hot isostatic pressing (HIP in English).

Transmission of multispectral zinc sulfide can be broad spectrum with flat spectrum. The transmission is in particular greater than 60% from 0.5 μm to 10 μm.

The refractive index of multispectral ZnS is, for example, between 2, 1 and 2.3 in the range A and in the visible range between 2.3 and 2.6.

Multispectral and preferably polycrystalline zinc sulfide is advantageous in view of its combination of optical, mechanical and chemical resistance properties.

The most well-known multispectral polycrystalline zinc sulfide is Cleartran ™.

Mention may be made of the multispectral ZnS product sold by the company II-VI or Crystaltechno Ltd. Mention may be made, as sellers of polycrystalline zinc selenide, of the companies Hellma, II-VI or Crystaltechno Ltd.

Advantageously to improve the mechanical strength, the insert comprising an outer face and an inner face, it comprises a mechanical and / or chemical protection layer on the outer face and possibly on the inner face.

The mechanical and / or chemical protective layer (preferably a coating - monolayer or multilayer -) can be chosen from at least one of the following layers:

- a layer comprising a zinc sulphide (in particular ZnS) in particular on an insert of ZnS _x Se _1-x , in particular ZnSe, for mechanical protection,

- a diamond layer, preferably amorphous for its properties of adhesion to the crystal of the insert, in particular with a thickness of at least 10nm or 20nm and preferably from 50nm to 300nm and even at most 100nm,

a DLC layer (for “diamond like carbon” in English), that is to say a layer based on carbon of the diamond type, preferably amorphous, in particular with a thickness of at least 10 nm or 20 nm and preferably 50 nm at 300nm and even at most 100nm.

Adding a sufficiently thin layer of ZnS over ZnSe does not degrade transmission and guarantees erosion resistance similar to massive ZnS. An example of a product is TUFTRAN ™ from Rohm & Haas. For example the material such as ZnS _x Se _1-x (including ZnS) can be coated with a layer of ZnS to protect it against acids and other specific solvents such as methanol etc.

As an alternative to ZnS, it is therefore possible to deposit, for example by chemical phase deposition (in particular PECVD) or vapor phase deposition (PVD), a diamond layer (or a DLC layer) without degrading the transmission and ensuring further erosion resistance. bigger. An example of manufacture is described in the publication of Osipkov et al. IOP conf. Ser. Material Science and Engineering 74 (2015) 012013. The insert can therefore be coated with a functional overlay (anti-scratch, anti-fog, etc.) with a different refractive index n is the index of the material of the dominant thickness.

The insert can be flat with parallel inside and outside sides of at most 2.

The inner face of the insert can be flush with the inner face of the glazing or be set back by up to 5mm.

Sir the inside face of the glazing (F2 or F4 if laminated glazing) can be glued to a plate, in particular of thickness 1 to 3mm, and even 1.5 to 2.5mm. It is, for example, optionally reinforced plastic (fibers, etc.), for example polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene (PE), polypropylene (PP), polyamide (PA66), acrylonitrile butadiene styrene (ABS), and their ABS-PC alloys, polystyrene (PS), acrylonitrile styrene acrylate ASA, based on formaldehyde polymer (polyoxymethylene POM), polybrominated terphenyl (PBT), preferably glass fiber filled for even more resistance, in particular PA66 GF30 (30% glass fibers)

This plate can be used to fix the thermal camera and / or a box. It can be drilled to the right of said through hole

It can also carry functional elements such as a visible camera and / a Lidar or any other sensor (rain, light, etc.). It has as many holes as necessary for the sensor (s) (hole for visible camera, for LIDAR, etc.)

The glazing according to the invention can be a laminated glazing, in particular a vehicle windshield (road, automobile in particular), in particular curved, comprising a first sheet of glass with said internal main face called F1 and an opposite main face ( called F2) and a second sheet of glass with said external main face called F4 on the inside of the passenger compartment (and the opposite main face F3), the first and second sheets of glass being linked by a lamination interlayer, in particular acoustic and / or tinted, in a particularly organic polymer material (in particular thermoplastic).

In particular, laminated glazing comprises:

- a first sheet of glass, optionally clear, extraclar or tinted in particular gray or green, preferably curved, forming exterior glazing, with first and second main faces respectively called face F1 and face F2, if a motor vehicle preferably of thickness d '' at most 2.5mm, even at most 2mm - in particular 1, 9mm, 1, 8mm, 1, 6mm and 1, 4mm - or even at most 1, 3mm or at most 1mm

a lamination interlayer, optionally clear, extraclear or tinted, in particular gray or green, made of a polymeric material, preferably thermoplastic and better still of polyvinyl butyral (PVB), preferably if a motor vehicle has a thickness of at most 1.8 mm, better still '' at most 1.2mm and even at most 0.9mm (and better still at least 0.3mm and even at least 0.6mm), in particular set back from the edge of the first glazing by at most 2mm and set back from the edge of a second glazing by at most 2mm, the lamination interlayer possibly having a cross section decreasing in a wedge shape from the top to the bottom of the laminated glazing (in particular a windshield),

- a second glazing, in mineral glass, preferably curved and preferably clear or extra-clear or even tinted, forming interior glazing, with third and fourth main faces, if a motor vehicle preferably has a thickness less than that of the first glazing, even d 'at most 2mm - in particular 1, 9mm, 1, 8mm, 1.6mm and 1, 4mm - or even at most 1.3mm or at most 1mm, the thickness of the first and second glazing preferably being strictly less than 4mm, even at 3.7mm.

The interior and / or exterior glass can be neutral (without coloring), or (slightly) tinted, in particular gray or green, such as TSA glass from Saint-Gobain Glass. The interior and / or exterior glass may have undergone a chemical or heat treatment of the hardening, annealing or tempering type (for better mechanical resistance in particular) or be semi-tempered.

Without departing from the scope of the invention, the interlayer may of course comprise several sheets of thermoplastic material of different natures, for example of different hardnesses to ensure an acoustic function, as for example described in the publication US Pat. No. 6,132,882, in particular a set of PVB sheets of different hardnesses. Likewise, one of the glass sheets can be thinned with respect to the thicknesses conventionally used. The interlayer may according to the invention have a wedge shape, in particular with a view to a HUD (Head Up Display) application. Also one of the sheets of the interlayer can be dyed in the mass.

As usual lamination interlayer, in addition to PVB, mention may be made of the flexible polyurethane PU used, a plasticizer-free thermoplastic such as ethylene / vinyl acetate (EVA) copolymer, an ionomer resin. These plastics have, for example, a thickness between 0.2 mm and 1.1 mm, in particular 0.3 and 0.7 mm.

The lamination interlayer can comprise another functional plastic film (transparent, clear or tinted), for example a poly (ethylene terephthalate) PET film carrying an athermic, electrically conductive layer, etc., for example, we have PVB / functional film / PVB between the faces F2 and F3.

The transparent plastic film can be between 10 and 100 μm thick. The transparent plastic film can be more widely made of polyamide, polyester, polyolefin (PE: polyethylene, PP: polypropylene), polystyrene, polyvinyl chloride (PVC), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polycarbonate ( PC). A clear film, in particular PET, is preferred.

As one can use for example a clear film of coated PET, for example XI R from the company Eastman, a coextruded film of PET-PMMA, for example of the SRF 3M® type, but also many other films (for example of PC, PE, PEN, PMMA, PVC), which are visually as transparent as possible and do not change in the autoclave with regard to their surface and consistency.

In order to limit heating in the passenger compartment or to limit the use of air conditioning, at least one of the glass sheets (preferably the exterior glass) is tinted, and the laminated glazing may also include a reflective or absorbent layer. solar radiation, preferably on the face F4 or on the face F2 or F3, in particular an electro-conductive transparent oxide layer called the TCO layer (on the face F4) or even a stack of thin layers comprising at least one TCO layer, or stacks of thin layers comprising at least one silver layer (in F2 or F3), the or each silver layer being disposed between dielectric layers.

We can combine a layer (silver) on face F2 and / or F3 and a TCO layer on face F4.

The TCO layer (of an electrically conductive transparent oxide) is preferably a layer of tin oxide doped with fluorine (SnO 2: F) or a layer of mixed oxide of tin and indium (ITO). Naturally the most sought-after application is for the glazing to be a windshield of a road vehicle (automobile) or even a rail vehicle (at moderate speed).

The glazing according to the invention may comprise at least a first sheet of glass comprising on a main face an opaque layer (masking) in particular an enamel (black, etc.) at the edge of the through hole (so as to mask the camera (s) for example. ).

The laminated glazing according to the invention may comprise a first sheet of glass comprising on a main face (for example the face F2) an opaque layer (masking) in particular an enamel (black, etc.) at the edge of the through hole (so as to mask the camera (s) for example) and / or a second sheet of glass comprising on a main face (for example the face F3 or F4) an opaque layer (of masking) in particular an enamel (black, etc.) at the edge of the through hole (of so as to hide the camera (s) for example).

It is also possible to provide a masking layer on at least one of the main faces of the lamination insert, in particular PVB.

The invention further relates to a vehicle, in particular autonomous or semi-autonomous, incorporating said device as defined above.

The invention also relates to an optimization method for forming the device as defined above in which for a camera with given Q, p (or even an inclination α of X 'with respect to the imposed or adjustable horizontal), one determines the smallest possible insert height D _min (with n and / or e possibly imposed or adjustable), preferably at most 20mm or 15mm (if possible), satisfying case a) and the height of insert Di ≥ D _min so that (yF-yco) ³ 0.5p / 2 (50% of the pupil in the triangle), and preferably (100% of the pupil in the triangle).

To arrive at the case D _min we can play on h, w or even α 'and even on n and e.

The invention also relates to an optimization method for forming the device as defined above in which, for a given insert height Di (with n and / or e optionally imposed or adjustable), for a camera with given p (or even an inclination α 'of X' to the horizontal imposed or adjustable), we determine a 0min as low as possible and preferably at most 40 °, 35 ° (if possible) satisfying the case a) and we choose 0³0min so that and preferably

To arrive at the 0 _min case, we can play on h, w or even α ee 'and even on n and e.

The invention finally relates to an optimization method for forming the device as defined above in which for a given insert height Di (with n and / or e optionally imposed or adjustable) and for a camera with 0 and (/ or ) p given (or even an inclination α 'of X' to the horizontal imposed or adjustable) we determine _{the lowest possible h min} satisfying case a) and we choose h ³ h≥h _min so that and preferably

To arrive at the case h _min we can play on w or even α '(and θ if not imposed) and even on n and e.

Certain advantageous but non-limiting embodiments of the present invention are described below, which can of course be combined with one another if necessary.

Figure 1 schematically shows a vehicle with a device 100 comprising a windshield with an insert and a thermal camera in the passenger compartment, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert.

Figure 2 schematically represents the insert and the thermal camera of figure 1 with the parameters (coordinates etc.) influencing the optimized positioning of the camera, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert.

FIG. 3 diagrammatically represents the insert and the thermal camera of FIG. 1 with exemplified parameters (example 1) influencing the optimized positioning of the camera, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert. FIGS. 3 'and 3 ”represent diagrams of the illumination of the infrared sensor of the thermal camera, in gray level for example 1 and a counterexample 1'.

FIG. 4 schematically represents the insert and the thermal camera of FIG. 1 with exemplified parameters (example 2) influencing the optimized positioning of the camera, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert.

Figure 4 ’shows a diagram of the illumination of the infrared sensor of the thermal camera, in gray level for example 2.

FIG. 5 diagrammatically represents the insert and the thermal camera of FIG. 1 with exemplified parameters (example 3) influencing the optimized positioning of the camera, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert.

Figure 5 ’shows a diagram of the illumination of the infrared sensor of the thermal camera, in gray level for example 3.

Figures 6a and 6b respectively show the variation of the ordinate y and the negative abscissa x of the points CO, E, F as a function of Q for case a) and case b).

Figures 7a and 7b respectively represent the variation of the ordinate y and the negative abscissa x of the points CO, E, F as a function of Di for case a) and case b).

Figures 8a and 8b respectively represent the variation of the ordinate y and the negative abscissa x of the points CO, E, F as a function of a for case a) and case b).

Figures 9a and 9b respectively show the variation of the ordinate y and the negative abscissa x of the points CO, E, F as a function of h for case a) and case b).

Figures 10a and 10b respectively show the variation of the y-coordinate and the negative x-coordinate of the points CO, E, F as a function of n for case a).

FIG. 1 schematically shows a windshield 100 according to the invention, in section with a thermal camera 9 placed behind the windshield facing a zone which is preferably situated in the central and upper part of the windshield. In this area, the camera can be oriented at a certain angle to the horizontal. In this example the camera is horizontal. In particular, the objective and the infrared sensor are oriented directly towards the image capture zone, in a direction parallel to the ground.

The windshield is a classic laminated glazing comprising:

- an outer sheet of glass 1 preferably tinted, for example TSA glass and 2.1 mm thick, with outer face F1 and inner face F2

- and an internal glass sheet 1 ', (or as a variant a plastic sheet) for example TSA glass (or clear or extraclear) and 2.1mm thick or even 1.6mm or even less, with face exterior F3 and interior F4 on the passenger compartment side

- the two glass sheets being linked to each other by an interlayer of thermoplastic material 3, most often of polyvinyl butyral (PVB) preferably clear, of submillimeter thickness optionally having a cross section decreasing in wedge shape of the top to bottom of the laminated glazing, for example a PVB (RC41 from Solutia or Eastman) approximately 0.76mm thick or alternatively if necessary an acoustic PVB (three-layer or four-layer) for example approximately 0.81mm thick , for example interlayer in three PVB sheets.

Conventionally and well known, the windshield is obtained by hot lamination of the elements 1, 1 'and 3.

The windshield 100 comprises on the outer face 11 for example (or preferably in F2 12 and / or on the face F3 13 or F4 14) preferably an opaque coating, for example black 6, such as a layer of enamel or black lacquer, over the entire surface of the glazing placed opposite the device incorporating the thermal camera (therefore all around the perimeter of the hole), including its housing 8 (plastic, metal, etc.), so as to hide it. The housing 8 can be fixed to a plate 7 glued to the face F4 by an adhesive 80 and to the roof 9.

The opaque layer 6 can extend beyond the area with the insert. Optionally the (lateral) extension of the opaque layer forming a band at the upper edge of the through-hole so that the windshield has an opaque band (black) along the upper longitudinal edge or even an opaque frame (black) over the entire periphery.

According to the invention, in the peripheral zone facing the camera, the windshield comprises a through hole 4 between the internal face 11 and the external face 14, a hole delimited by a side wall 10 of the laminated glazing ( glass 1 / PVB 3 / glass 1 '), said through hole comprising: - an insert 2 made of transparent material in a range A of wavelengths in the infrared which goes at least from 9.5 to 10.5 μm and preferably from 8 to 12 μm, the insert being of given thickness e,

- Between the insert and the side wall, the insert fixing means in particular in the form of a ring 5 made of flexible material, polymer, the fixing means being in particular glued to the side wall.

The material of the insert 2 is also transparent in the visible at a reference wavelength between 500nm and 600nm

It can be transparent in the visible at least in a range B ranging from 550 to 600nm. The material of the insert 2 has an infrared transmission of at least 50% and better still of at least 65% in said range A and a light transmission of at least 30% and better still of at least 40% along the length. of reference wave and better still in the range B. The material of the insert 2, preferably polycrystalline, is chosen from:

- a zinc compound comprising selenium and / or sulfur or

- a compound comprising a barium fluoride.

In particular we choose:

- a compound comprising a multispectral zinc sulphide, in particular obtained after hot isostatic pressing, in particular including selenium, such as ZnS _x Se _1.x with x preferably at least 0.97, in particular multispectral ZnS

- or a compound comprising a zinc selenide, in particular ZnSe, in particular including sulfur, such as ZnS _x Se _1.x with y of at least 0.97

. a compound comprising a barium fluoride in particular including calcium and / or strontium, in particular with i and j preferably at most 0.25 or alternatively with i preferably at most 0.25, in particular BaF ₂ .

The insert 2 has an outer face 21 and an inner face 22 and here it preferably comprises a mechanical and / or chemical protection layer 2 'on the outer face and possibly on the inner face. It is a coating chosen from a layer comprising a zinc sulfide, a diamond layer or a DLC layer.

Preferably, one can choose a multispectral ZnS bare or covered with a protective layer of zinc sulphide or a ZnSe covered with a protective layer of zinc sulphide.

The through-hole 4 can alternatively be a notch therefore a through-hole preferably opening on the roof side. The through hole (and insert) may be in another region of the windshield or even in other glazing of the vehicle.

The glazing of the vehicle can be monolithic.

The insert is of a given thickness e, in particular from 3 to 10mm, made of a material of refractive index n in the range A, in particular from 1.35 to 4.5.

The insert is preferably of circular or quasi-circular shape, the entry face being inscribed in a rectangle or square of width Wi and height Di with aspect ratio Di / Wi of at least 0.8 and at plus 1, 1, with Di> Wi, defining a center O which is the intersection of the diagonals of said rectangle.

The so-called thermal camera 9 comprises a circular entrance pupil 91, with a height p i (diameter generally) and an infrared detection system in the range A and an objective, the camera being defined by:

-an optical axis X 'passing through the center C of the pupil, C facing the insert,

-a vertical viewing angle θ of at least 10 °, 20 ° and in particular of at most 70 °, 60 °.

The camera has a given volume defined by a contact point T (a corner / upper front plane of the lens / front or rear of the lens) able to first touch here a plastic plate 7 on the internal face of the camera. glazing for example of 1.5mm perforated to the right of the through hole 4. This plate can be used to fix the camera 9.

T is in a PO plane passing through O and C (where we define Tv called virtual contact point being the projection of T in said PO plane), w is the distance along X algebraically in the PO plane of T or Tv and h is the distance along Y in the plane PO between C and T or Tv; the entry face 21 of the insert having an inclination defined by an angle a with respect to X and of at least 20 °, 30 °, 35 °, 40 ° and up to 60 ° or even 90 ° or 80 ° relative to the horizontal, in particular X being at most 20 ° relative to the horizontal.

FIG. 2 schematically represents the insert and the thermal camera of FIG. 1 with the parameters (coordinates, etc.) influencing the optimized positioning of the camera 9, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert 2.

In relation to figure 2 we define three limiting conditions Condition on the upper radius (via Dt2)

The borderline case corresponds to the slope line

[Math 16] and which passes through the point S with coordinates:

[Math 17]

And

[Math 18]

So, straight line Dt2 of equation:

[Math 19]

This is the limit case, the condition is respected if we are under this line Dt2 therefore: [Math 20]

Condition on the lower radius (Dt1) Let the line of slope [Math 21] and which passes through point I, the coordinates of which must be found thanks to the laws of Descartes. Let i _{1 be} the angle of incidence of the ray on the internal face of the insert, we have (because sum of the angles of a triangle equal to pi):

[Math 22] let i _{2 be} the angle of the ray in the insert with optical index n, we have [Math 23]

Let now be the coordinates of point B:

[Math 24] and

[Math 25] and the distance between point B and point I which is equal to: [Math 26] with e the thickness of the insert.

We have

[Math 27] which allows to calculate the coordinates of point I: [Math 28]

And

[Math 29] either according to the system parameters:

[Math 30]

[Math 31]

This gives the equation of the line Dt1: [Math 32]

In the same way as above, this is the limit case, we must be above this line Dt1 so:

[Math 33]

The most favorable case (rear point of the triangle, denoted C ₀ ) has for coordinates (point intersecting between the line dt1 and the line dt2):

[Math 34]

[Math 35]

Even in the asymptotic case where e is very small (limit e tends to 0) we have: [Math 36]

Or like

[Math 37]

[Math 38] we have in all cases

[Math 39] which justifies shifting up the optical center of the camera.

Mechanical condition

Let h be the height between the center C of the pupil and the "corner which touches" denoted T and w the horizontal distance between the center of this pupil and the "corner which touches"

We have as equation of the line Dt3:

[Math 40] This is the limit case equation, the condition is satisfied if: [Math 41]

Since it is a question of finding the back position of the camera (in x) that satisfies the other criteria, it is more telling to express the condition on x in terms of y:

[Math 42]

[Math 43]

In particular in the case where we started at _y = y _co [Math 44] w can be positive or negative (but in general quite small in absolute value) and that x is always negative taking into account the orientation of the axes.

The reference point for the position of the camera is the position of the point C center of the entrance pupil of the camera but so that the whole field of the camera is used without shading on the edges, the whole of the pupil of height p must be inside the triangle formed by the three lines Dt1, Dt2 and Dt3.

Coordinates of point F [Math 45]

[Math 46]

Coordinates of point E [Math 47]

[Math 48]

Examples

FIG. 3 diagrammatically represents the insert and the thermal camera of FIG. 1 with exemplified parameters (example 1) influencing the optimized positioning of the camera 9, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert 2.

Figures 3 "and 3" represent illumination diagrams of the infrared sensor of the thermal camera, in gray level for example 1 and a counterexample T.

The parameters are listed in table 1. [Table 1]

C is placed in the EFCO triangle with y _c = y _co = 2.2mm and x _c is equal to -16.5mm. C1 the lowest point of the pupil is on the right Dt1 with y _c1 = 1.07mm C2 the highest point of the pupil is on the right Dt1 with y _c2 = 3.34 mm The coordinates of E are -11 , 09; -0.45 The coordinates of F are -17.27; 3.56 The abscissa of CO is x _co = -23.6mm

Since w is positive then T is on the front plane of the camera

The sensor illumination pattern (from the outside) is uniform (white is the maximum illumination from the outside homogeneous).

In a counter-example 1 'with y _c = 0 and we clearly show that we lose the entire bottom of the image (cf. black part in the lower part of figure 3 ”).

In terms of effective lower vertical field of view downwards, we pass 8 ° by 12 ° so we have a gain of 4 ° by placing the camera such that y _co = 2.2mm and not by centering it on the X axis.

This corresponds to a gain of vision in height of approximately 2m for an object / a living being 30m from the windshield.

Compared to example 1, only the input data p is modified and is equal to 5.67mm the pupil is too large to fit entirely into the COFE triangle, we center at best to fit a maximum fraction of the pupil. There is shading at the top and bottom of the image on the sensor (see black parts in Figure 4 ’).

FIG. 5 diagrammatically represents the insert and the thermal camera of FIG. 1 with exemplified parameters (example 3) influencing the optimized positioning of the camera, it is a partial sectional view in a plane PO passing through the center C of the pupil of the camera and a center O of the insert 2.

The parameters are listed in table 2 [Table 2]

The camera is too bulky and has a large Q. This corresponds to case b) for which the point of T is far enough back and the triangle according to a) (C above Dt1 and under Dt2) no longer exists.

We choose to place C td y _c = y _co and as close as possible to the curve Dt1.

Although there are dark areas at the top and bottom of the image those have been minimized by the proposed placement. This also corresponds to an equal compromise between top and bottom shading.

FIGS. 7a and 7b respectively represent the variation of the ordinate y and of the negative abscissa x of the points CO, E, F as a function of Di for the case a) and the case b). FIGS. 8a and 8b respectively represent the variation of the ordinate y and of the negative abscissa x of the points CO, E, F as a function of a for the case a) and the case b). FIGS. 9a and 9b respectively represent the variation of the ordinate y and of the negative abscissa x of the points CO, E, F as a function of h for the case a) and the case b).

The parameters are listed in table 3 [Table 3]

On each of the graphs of figures 6a to 10b the point of intersection R (for y) and R ’(for x) of the curves gives the moment when the triangle ceases to exist (tilting towards case b):

- when Q too large, we are in case b)

- when Di too small, we are in case b)

- when a too small we are in the case b)

-or when h too big we have in case b).

In particular for case a) on sets of graphs:

- for

- for -and for for case b):

-y _Co goes from 1mm to 3mm.

Claims

1. Device (100 to 500) characterized in that it comprises:

- vehicle glazing, in particular automobile or rail, in particular windshield, rear window, side glazing, of a given thickness E1, glazing having an external main face (11) facing outwards and an internal main face (14 ) passenger compartment side, glazing comprising, in a peripheral zone preferably in the upper part of the glazing, a through hole between the internal face and the external face, hole delimited by a side wall of the glazing,

- in said through-hole, an insert (2) made of transparent material in a range A of wavelengths in the infrared spectrum beyond 2.5 μm, ranging at least from 9.5 to 10.5 μm and preferably from 8 to 12 μm, the insert being of a given thickness e, made of a material of refractive index n in the range A, with an inlet face (22) facing the passenger compartment and an outlet face (21), the insert , preferably being of circular or quasi-circular shape, the inlet face (22) being inscribed in a rectangle or square of width Wi and height Di with aspect ratio Di / Wi of at least 0.8 and d ' at most 1,2, preferably Di> Wi, with Di of at most 35mm, in particular of at least 5mm, defining a center O which is the intersection of the diagonals of said rectangle,

- a so-called thermal camera (9), arranged on the internal face side so as to receive electromagnetic radiation after passing through said insert, thermal camera comprising an entrance pupil (91), in particular circular, with a height p, and a detection system infrared in range A and a lens, the camera being defined by:

- a vertical viewing angle Q of at least 10 ° and in particular at most 70 °, the camera being of a given volume defined by a contact point T able to first touch the glazing, or a plate (7) on the internal face of the glazing, or the insert, or a part in the peripheral environment of said glazing, in the mounted position in a vehicle, the orthogonal coordinate system (O, X, Y, Z) is defined in which X is an axis parallel to the optical axis X, oriented towards the external face (21), Z the axis normal to the optical axis, the Y axis normal to X in the plane containing PO oriented towards the top of the glazing, Z normal to PO T being in a plane PO passing through O and C where we define Tv said point of virtual contact being the projection of T in said plane PO, w being the distance along X and algebraically in the plane PO of T or Tv and h is the distance along Y in the plane PO between C and T or Tv, the entry face (22) of the insert having an inclination defined by an angle a with respect to X, in that we define a first line Dt1 [Math 49] we define a second line Dt2 [Math 50]

Dt1 and Dt2 are secant in CO (x _co , y _co ) with [Math 51]

[Math 52] we define a third line Dt3 [Math 53] Dt1 and Dt3 are secant in

Dt2 and Dt3 are secant in

[Math 54]

[Math 55]

[Math 56]

[Math 57] x _c being a negative value, y _c a positive value, in that in a case a) is inside a triangle of vertices and, at at least 50% of the pupil being positioned in said triangle including E; or in a case b) when [Math 58] so we then define a point K of intersection between a straight line

[Math 59]

[Math 60] and

[Math 61]

2. Device according to claim 1 characterized in that in case a) at least 70% or 80% or 90% of the pupil is positioned in said triangle C0FE including E.

3. Device according to one of the preceding claims characterized in that in case a)

4. Device according to one of the preceding claims characterized in that [Math 62] and / or 29

[Math 63]

5. Device according to one of the preceding claims, characterized in that Θ is at least 20 ° and in particular at most 50 °.

6. Device according to one of the preceding claims, characterized in that Di is at most 20mm.

7. Device according to one of the preceding claims, characterized in that X ’forms an angle of at most 20 °, 10 ° with the horizontal and / or at most an angle equal to θ / 2 ± 2 °.

8. Device according to one of the preceding claims, characterized in that the material of the insert is germanium, zinc sulphide.

9. Device according to one of the preceding claims characterized in that the material of the insert has an infrared optical transmission of at least 50% and better still of at least 60%, 65% or 70% in said range A and a light transmission of at least 30% and better still of at least 40% at the reference wavelength of between 500nm and 600nm and better in a range B of 550 to 600nm.

10. Device according to one of the preceding claims, characterized in that the material of the insert is chosen from:

- a zinc compound comprising selenium and / or sulfur or

- a compound comprising a barium fluoride.

11. Device according to one of the preceding claims characterized in that the glazing forms a laminated glazing, in particular a windshield, in particular curved, the laminated glazing comprising a first sheet of glass (1) with said internal face called F1 and an opposite face and a second sheet of glass or plastic (1 ') with said external face called F4 on the interior side of the passenger compartment, the first and second sheets being linked by a lamination interlayer (3), in particular acoustic and / or tinted made of a polymeric material.

12. Vehicle, in particular autonomous or semi-autonomous, integrating said device according to one of the preceding claims

13. Optimization method for forming the device defined according to one of claims 1 to 11 characterized in that for a camera with Θ, p, given and an insert height D _min is determined as small as possible, preferably 20mm at most, satisfying case a) and the insert height is chosen so that , and preferably

14. Optimization method for forming the device defined according to one of claims 1 to 11 characterized in that for a given insert height Di, for a camera with given p, we determine a 0min as low as possible and preferably at most 40 ° satisfying case a) and we choose 0> 0min so that, and preferably

15. Optimization method for forming the device defined according to one of claims 1 to 11 characterized in that for a given insert height Di and for a camera with θ , p given, we determine _{the lowest possible h min} satisfying case a) and we choose h ≥ h _min so that and preferably