ILLUMINABLE GLASS ROOF OF VEHICLE

Abstract

Illuminatable vehicle glass roof One aspect of the invention relates to a glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) illuminable by a light source (4), the glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) comprising a first sheet of glass (1), a second sheet of glass (2), between which are included a lamination interlayer and a holographic layer (6) comprising a hologram in volume and in reflection, the hologram being adapted to diffract towards the outside of the glass roof, via the second sheet of glass (2), at least a part of rays guided in the glass roof. Figure to be published with the abbreviation: Figure 1

Description

Title of the invention: ILLUMINABLE GLASS ROOF FOR VEHICLE

[0001] The present invention relates to illuminateable automobile roofs.

[0002] It is known to integrate inorganic light-emitting diodes, also called LEDs for "Light-Emitting Diode" in English, at the edge of single or laminated glazing, so that the light emitted by the diodes enters through the edge of a sheet of glass and is guided by the latter to a diffusing element, also called a light extraction means.

[0003] In particular, there are illuminating glazings, cited for example in patent application FR3034501A1, whose diffusing element (or means of extraction) is a diffusing layer comprising diffusing dielectric particles in a matrix.

[0004] There is a need to produce an illuminating glazing from which light is extracted with good extraction efficiency and discreet in the off state.

[0005] To this end, one aspect of the invention relates to a laminated glass roof for a vehicle comprising: • a first sheet of mineral glass, called the outer sheet, transparent, having a first principal face called face Fl and a second principal face called face F2 opposite, with a refractive index nv at a first wavelength XI in the visible range preferably greater than or equal to 1.5 • a second, internal sheet of glass, made of organic or mineral glass, transparent, with a refractive index of n0 to XI, having a principal face called face F3 and an opposite principal face called face F4, • between face F2 and face F3, a dielectric laminated interlayer made of polymer material, comprising at least one layer of laminated interlayer, the glazed roof comprising, between face F2 and F3, in that order moving away from F2: preferably one or more upper dielectric intermediate layers, transparent, with given refractive indices in the visible, in particular the upper intermediate layer(s) are interlayer layers,

[0006] the first sheet being tinted and / or among the upper intermediate layer(s) a first layer being tinted, in particular a first tinted interlayer layer,

[0007] when several upper intermediate layers are tinted, the first tinted layer is the tinted layer closest to face F3, • a first holographic, transparent, dielectric layer, comprising a first functional zone with a first volume hologram, diffracting at XI, the first functional zone having a refractive index nm at XI Preferably, between the first functional zone and the F3 face, one or more lower intermediate layers, transparent, dielectric, in particular interlayer,

[0008] n2 being the lowest refractive index at XI in the visible:

[0009] a) among the refractive indices of the upper intermediate layer(s), in particular the interlayer, between the first excluded holographic layer and up to the first included tinted layer

[0010] b) or in the absence of a tinted upper intermediate layer or in the absence of an upper intermediate layer n2 being equal to nv

[0011] ni being the lowest refractive index at XI among the refractive indices of the possible lower intermediate layer(s), of the first functional zone and n0, with n2 <ni

[0012] the roof being adapted to receive a beam of light in the second glass sheet, of light rays injected at XI into the second glass sheet, with a range 01 of angles of incidence in the second glass sheet, being guided in the roof until reaching the first hologram and with 01 such that arcsin (n2 / n0) <01 <arcsin ( ni / n0)

[0013] the optical function of said first hologram being chosen such that a portion of the rays guided in the roof (in the range 01) reaches the first hologram and are diffracted and extracted from the roof on the side of face F4, diffracted rays defined by a range of angles of incidence 02 in face F4 (in the second sheet of glass), and between -arcsin ( l / n0) and arcsin ( l / n0).

[0014] In particular, the range 01 represents the angles of incidence with respect to the vector locally normal to the lower face of the layer at the point of impact of the guided rays.

[0015] The invention advantageously allows the extraction of light waves at a specific range of angles using a hologram. In particular, the use of a volumetric hologram is especially advantageous because these holograms benefit from high diffraction efficiency, which translates into high luminance. Furthermore, holograms possess wavelength and angular selectivity that increases with their thickness, meaning they can be highly transparent. These two properties make holograms particularly attractive for sunroof lighting, as most prior art solutions based on light diffusion suffer from a compromise between blurred vision through the glazing and efficient light extraction. Efficiency is defined as extraction as the whole of the light which is diffracted by the hologram on the whole surface so as to exit the glass (in the indicated angle range) relative to the light injected into the guide.

[0016] Furthermore, an intrinsic efficiency of the hologram is defined; that is, the fraction of light incident on the hologram that is redirected by it. This can be chosen from at least a threshold value depending on the size of the system (hologram and guide). The larger the system, the lower the threshold value is, to ensure homogeneous illumination. For example, an intrinsic efficiency of 30% is well suited for an interaction length with the hologram, typically the length of the hologram, of one meter.

[0017] In particular, the laminated hologram is designed to diffract the light guided out of the roof. For example, light sources placed on the edge of the second pane of glass can advantageously read the hologram to provide a luminous (or non-illuminated) sunroof, potentially with a graphic design for decorative applications. In this way, it is possible to achieve an interesting compromise between transparency and extraction efficiency.

[0018] The invention takes advantage of the thickness of the tinted material (first tinted sheet or possible first tinted layer). Indeed, if the most grazing rays are guided into the second sheet by total internal reflection with the interface with the intermediate layer (lower intermediate layer of interlayer for example), other less grazing rays propagating in the glazing by refraction reach the tinted material and are quickly absorbed after a few bounces following their refraction and reflection.

[0019] The tinted thickness thus creates angular filtering that eliminates the need to manage less grazing angles. Therefore, the tinted material offers two advantages. The first advantage is that it imposes large guided angles. By registering the hologram to operate within this angular range, the angles coming from outside are far from the Bragg condition, and therefore not optimal for diffraction. The second advantage is that by attenuating the light coming from outside, there is necessarily less stray light that can interact with the hologram. Thus, these two advantages allow us to obtain, firstly, greater brightness with less blur than a diffuser, and secondly, fewer optical defects than a hologram simply between two lenses.

[0020] In particular, the first sheet of glass and / or any tinted intermediate layer (of PVB or PET interlayer etc) are sufficiently absorbent, taking into account their absorption coefficients and their thicknesses, so that on a rebound, i.e. their refraction from face F3 to face Fl, then their reflection on face Fl, and finally their refraction back to face F3, the light intensity is reduced by at least 50%.

[0021] Light intensity can be measured by transmission spectroscopy. Typically the extinction coefficient k, imaginary part of the complex refractive index for a glass called VG10 of the applicant of 2mm (or for a tinted PVB of 0.76mm with TL of 40% is on the order of 10-8 in the visible (in particular at the reference wavelength and even over the spectral range of the source).

[0022] It is preferable that the first tinted layer, if any, or the first sheet of tinted glass be over-tinted, and therefore sufficiently absorbent. It is preferable that the first tinted layer be passive rather than a variable-tint layer of an electrically controlled device. However, functionalities such as a variable-tint or variable-blur layer can be added, preferably between face F2 and a tinted layer (preferably the first tinted layer).

[0023] A tinted intermediate layer (interlayer, upper and / or lower intermediate layer) according to the invention may have a light transmission of at most 50%, or at most 40%, or at most 30%, or at most 20%.

[0024] For the first tinted layer, a color different from or the same as that of the first sheet of glass, if also tinted, can be chosen. For example, the first sheet of tinted glass is green, blue, or gray, and the first tinted layer, preferably an interlayer, for example made of PVB material, is blue or gray. At least one other intermediate layer, preferably an interlayer, clear, for example clear PVB, can be added, closer to face F2 than the first tinted layer or closer to face F3.

[0025] At least one lower intermediate layer may be a (lower) adhesive layer (distinct and) in contact with the first holographic layer and even with face F3 and / or an upper intermediate layer may be an (upper) adhesive layer in contact with the first holographic layer and even with face F2, a local (upper and / or lower) adhesive layer (extending little or not at all beyond the first holographic layer, for example less than 1 cm beyond) or an extended adhesive layer (extending over at least 80%, or even at least 90%, 95% of the main face of the roof to form an interlayer layer of (upper and / or lower) lamination. There may be local lower and upper adhesive layers, or a local lower adhesive layer and an extended upper adhesive layer, or an extended lower adhesive layer and a local upper adhesive layer, or extended lower and upper adhesive layers.

[0026] The first holographic layer may be a coating, preferably on face F3 or even on face F2, or a (self-supporting) film. The first holographic layer may be:

[0027] - in contact with a superior adhesive layer (extensive or local) which is by example a low refractive index film, attached or glued to face F2

[0028] -and / or in contact with a lower intermediate layer (extended, in particular PVB-based layer, or local) attached or glued to face F3.

[0029] In addition to the characteristics mentioned in the preceding paragraph, the glazed roof according to one aspect of the invention may have one or more additional characteristics from among the following, considered individually or according to all technically possible combinations:

[0030] - the first hologram is in reflection,

[0031] - n0 is between 1.5 and 1.62 at XI,

[0032] - n2 is less than or equal to 1.48 to XI or even to 1.45 and preferably equals at least 1.3

[0033] - nv is between 1.5 and 1.55 at XI,

[0034] - n2 is less than or equal to 1.45 with nv greater than n2 (and preferably with a upper intermediate layer which is an adhesive layer, particularly local or extensive (in particular a layer of cross-linked material),

[0035] - ni is greater than or equal to 1.48 and ni is greater than n0 and preferably an interlayer The lower intermediate layer is an adhesive layer (local or extensive, in particular a PVB-based layer),

[0036] - niest less than or equal to nHi and even nr nHi is at most 0.2 or 0.1, (so that the first hologram receives as much light as possible),

[0037] -the first hologram is a preferably sinusoidal diffraction grating,

[0038] - the first hologram is a set of off-axis Fresnel zones, in particular obtained from a microlens array, and in particular obtained from the recording of the field transmitted by a microlens array.

[0039] The glazed roof may include a light source optically coupled to the second sheet, a monochromatic light source at said first wavelength XI and a full mid-height bandwidth preferably of at most 30nm, XI is preferably chosen from a first range LB1 from 450 nm up to 510 nm excluded or from a second range LB2 from 510 nm up to 560 nm excluded, or from a third range LB3 from 560 to 650 nm, or better from 620nm to 650nm (in particular XI = 532 nm±30nm, which corresponds to green, X2 = 480nm±30nm, which corresponds to blue, or even X3 = 680nm±30nm, which corresponds to red).

[0040] An upper intermediate layer may be an interlayer layer of index n; equal to 1.48 in the visible, and XI is in the first range LB2 or LB1, preferably LB2.

[0041] The glazed roof includes a polychromatic light source (comprising one or more light sources, in particular diodes), optically coupled to the second sheet, the polychromatic light source emitting:

[0042] - at said first wavelength XI chosen from within a first range which is in a first range LB1 from 450 nm up to 510 nm excluded or in a second range LB2 from 510 nm up to 560 nm excluded, or in a third range LB3 from 560 nm up to 650 nm, or better from 620 nm to 650 nm, (the light source having in particular a first source with a full width at half maximum preferably of 30 nm centered on XI)

[0043] - to a second main wavelength X2 distinct from XI and chosen in a a second range distinct from the first range and which is in the first, second or third ranges LB1, LB2, LB3, (the light source having in particular a second light source with a full half-height bandwidth preferably of 30nm centered on X2) and preferably to a third main wavelength X3 distinct from XI and X2 and chosen in a third range distinct from the first range and the second range which is in the first, second or third ranges LB1, LB2, LB3, (the light source having in particular a third light source having a full half-height bandwidth preferably of 30nm centered on X3), preferably the first range is in LB2, the second range is in LB1, the third range is in LB3.

[0044] The first so-called multiband hologram (for example multiplexed) also diffracts at the second wavelength X2, the first functional zone having a refractive index nH2 at X2 or even diffracts also at the third wavelength X3, the first functional zone having a refractive index nH3 at X3 or in that the roof comprises a second hologram diffracting at X2 between the first hologram and the face F3, with a second holographic layer having a second functional zone having a refractive index nH2 at X2 and optionally the roof comprises a third hologram diffracting at X3, between the second hologram and the face F3, with a third holographic layer with a third functional zone having a refractive index nH3 at X2,

[0045] n2a being the lowest refractive index at X2 in the visible:

[0046] a) in the case of a second functional zone, among the refractive indices at X2 of the lower intermediate layer(s) above (going towards face F2) the second functional zone, the first functional zone, the upper intermediate layer(s) and up to and including the first tinted layer,

[0047] b) or in the case of a first multiband hologram, among the refractive indices of the upper intermediate layer(s) (in particular the interlayer) between the first excluded holographic layer and up to the first included tinted layer

[0048] c) or in the absence of a tinted upper intermediate layer or upper intermediate layer, n2a being equal to nva with nva the X2 refractive index in the visible of the first sheet

[0049] and

[0050] i) nia being the lowest refractive index at / .2 among the refractive indices of the possible lower intermediate layer(s) below the second functional zone (towards face F3), nH2 being the index of the second functional zone, and nOaqui being the refractive index at / .2 in the visible of the second sheet

[0051] j) or in the case of a first multiband hologram, nla being the lowest refractive index at / .2 among the refractive indices of the possible lower intermediate layer(s) (below the first functional zone), the index nH2 of the first functional zone, and nOa which is the refractive index at / .2 in the visible of the second sheet

[0052] the optical function of said second hologram or of the first multiband hologram being chosen such that a portion of light rays injected at θ.2 into the second glass sheet, guided in the roof (in the range θ1), reaches the second hologram or the first multiband hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of incidence angles θ2 at face F4 (in the second glass sheet), and between -arcsin(θ / nOa) and arcsin(θ / nOa),

[0053] and optionally, n2b being the lowest refractive index at θ.3 in the visible:

[0054] a') in the case of a third functional zone, among the refractive indices at θ.3 of the or lower intermediate layers above (going towards face F2) the third functional zone (including the second functional zone), the first functional zone, the upper intermediate layer(s) and up to and including the first tinted layer,

[0055] b') or in the case of a first multiband hologram, among the refractive indices of the upper intermediate layer(s) (including interlayer), between the first holographic layer (excluding the first layer) and the first tinted layer (inclusive).

[0056] c') or in the absence of a tinted upper intermediate layer or an inter-layer upper median, n2b being equal to nvb with nvb the refractive index at / .3 in the visible of the first sheet

[0057] and

[0058] nB, which is the lowest refractive index at / .3 among the refractive indices of the possible lower intermediate layer(s) under the third functional zone (towards face F3), the index nH3 of the third functional zone, and nOb, which is the refractive index at / .3 in the visible spectrum of the second sheet

[0059] the optical function of said third hologram or of the first multiband hologram being chosen such that a portion of light rays injected at / .3 into the second glass sheet, guided in the roof, (in the range 01), reaches the third hologram or the first multiband hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of angles of incidence 02 in face F4 (in the second glass sheet), and between -arcsin (l / nOb) and arcsin (l / nOb)

[0060] for a given observation direction in the range 02:

[0061] - the first XI diffracting hologram having a maximum diffraction efficiency in a first sub-range of 01a with a width of at least 1°

[0062] - the second hologram or the first multiband hologram diffracting at X2 having maximum diffraction efficiency in a second sub-range of 01b with a width of at least 1° and partial or disjoint overlap of 01a

[0063] - the possible third hologram or the first multiband hologram, dif fracting at X3, having maximum diffraction efficiency in a third sub-range of 01c with a width of at least 1° with partial or disjoint overlap with first and second sub-ranges 01a and 02a (the set of 01a, 01b, 01c is preferably at least 60%, 80% of 01).

[0064] nm and nH2 are not necessarily distinct, as the medium may or may not be dispersive. For example, it is possible to have two or three index modulations around a single index nH. In particular, nH3 is distinct from nHi and nH2.

[0065] The first multiband hologram is for example a multiplexed hologram, a linear combination of optical functions (here in particular two optical functions or three optical functions).

[0066] Alternatively, the roof comprises a stack of a first and a second hologram, in particular a lower intermediate layer forming the second holographic layer comprising said second functional zone in optical contact via local adhesive or lamination interlayer, with the first functional zone.

[0067] There is a stacking of the first, second, and third holograms, and in particular with a second functional zone, a lower intermediate layer forming the second holographic layer comprising said second functional zone in optical contact, via local adhesive or interlayer, with the first functional zone, and with a separate third functional zone, another lower intermediate layer forming the third holographic layer comprising said third functional zone in optical contact, via local adhesive or lamination interlayer, with the second functional zone. In one embodiment, the second hologram may be multiband with two optical functions for X2 and X3.

[0068] The glass roof may include:

[0069] - a first upper intermediate layer, an interlayer, made of adhesive material cross-linked, with a refractive index of n2, preferably of no more than 1.45 to XI

[0070] - a first lower intermediate layer, of interlayer, of refractive index of at least 1.48 to XI, in particular in thermoplastic material, especially PVB, or EVA (thermoplastic or cross-linked)

[0071] - a second sheet of mineral glass.

[0072] The holographic layer is a photopolymer; the first functional zone has a refractive index modulation dn around a refractive index nH0 at a visible inscription wavelength X0, which is preferentially in the spectral band of a monochromatic or polychromatic light source optically coupled to the second layer. Advantageously, this preferential characteristic avoids the need for pre-compensation, which would require a change in the reference angle to anticipate the difference in wavelengths.In particular, the holographic layer comprises a multiband hologram diffracting at XI, X2, X3, or the roof comprises second and third holograms diffracting at X2, X3, and X0 respectively, within a spectral band (specifically LB2) including the middle value among XI, X2, X3, and even the second and third holograms have distinct inscription wavelengths in the visible X'0 and X'0, distinct from X0, within a spectral band including a distinct middle value among XI, X2, X3 (specifically LB1 and LB3). In particular, the index modulation is small around nHi, nHi being dependent on the wavelength to which the material is exposed.

[0073] The number of upper intermediate layers is denoted N. N is, for example, at most 4, 3, 2, or 1, preferably at least 1, or even 0 if the first holographic layer is capable of bonding the sheets (sufficient adhesion to the sheets). The upper intermediate layers can have various possible functionalities: adhesive layer, in particular lamination interlayer, or other tinted, functional layer support (electrically conductive, heating, low-emissivity, athermal, etc.). Each upper intermediate layer can have a submillimeter thickness and is, for example, a film at least 30 µm or 50 µm thick.

[0074] An upper or lower intermediate layer may comprise a thermoplastic polymer sheet, in particular adhesive to glass sheets.The polymers are chosen from polyvinyl butyral (PVB), polyurethanes (PU), polyureas, ethylene vinyl acetate (EVA), polyolefins (including polyethylene (PE), polypropylene (PP), or polyisobutylene (P-IB)), polyvinyl chloride and its derivatives (e.g., poly(vinyl dichloride) (PVDC)), styrenic polymers (e.g., polystyrene (PS), acrylostyrene butadiene (ABS), styrene acrylonitrile (SAN)), polyacrylics (including polyacrylonitrile (PAN) and poly(methyl methacrylate) (PMMA)), polyesters (including poly(ethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT)), polyoxymethylene (POM), polyamides (PA), fluoropolymers such as polychlorotrifluoroethylene (PCTFE), Polycarbonates (PC), aromatic polysulfones including polysulfone (PSU), polyphenylene ether (PPE), epoxies (EP) alone or in mixtures and / or copolymers of several of them.

[0075] A layer of laminated interlayer, lower intermediate layer or super The outer layer can be a sheet or foil made of PVB or PU (flexible) or a thermoplastic without plasticizer (ethylene / vinyl acetate (EVA) copolymer, etc.), each sheet having, for example, a thickness between 0.2 mm and 1.1 mm, specifically 0.38 mm and 0.76 mm. Preferably, any interlayer, in foil form, made of PVB, comprises 70% to 75% PVB, 25% to 30% plasticizer, and less than 1% additives. There are also PVB foils with little or no plasticizer, such as the "MOWITAL LP BF" film from KURARAY. The lamination interlayer may also be or include a poly(vinyl butyral) (PVB) based sheet containing less than 15% by weight of plasticizers, preferably less than 10% by weight and even better less than 5% by weight and in particular without plasticizer and especially of a thickness of no more than 0.15mm in particular of 25 to 100pm, 40 to 70pm and even 50pm, for example the Kuraray Mowital® product.

[0076] The lamination interlayer may be acoustic, in particular comprising or being made of acoustic PVB (three-layer, four-layer, etc.). Thus, the lamination interlayer may comprise at least one middle layer made of a viscoelastic plastic material with vibro-acoustic damping properties, notably based on polyvinyl butyral and a plasticizer, and the interlayer itself, and further comprising two outer layers of standard PVB, the middle layer being between the two outer layers. Examples include the acoustic PVBs described in patent applications WO2012 / 025685 and WO2013 / 175101, particularly tinted ones as in WO2015079159.

[0077] The upper intermediate layers have various possible functionalities: adhesive layer, laminating interlayer, or other. Each upper intermediate layer has a submillimeter thickness and is, for example, a film at least 30 µm or 50 µm thick.

[0078] The lamination interlayer may be single-layered and may preferably be the first upper intermediate layer or a tinted film. The lamination interlayer is preferably multi-layered and may include, in particular, two, three, or four adhesive layers, including adhesive films or sheets. Specifically, the lamination interlayer may include a clear (in particular, without added dyes) tinted upper intermediate layer and a clear lower intermediate layer. The lamination interlayer may also include a clear or tinted upper intermediate layer and a clear lower intermediate layer in adhesive contact with the holographic layer. The layers forming the lamination interlayer may be made of distinct materials, in particular at least one thermoplastic layer and another layer that is a cross-linked adhesive.For example the lower intermediate layer is a thermoplastic layer, in PVB or EVA for example, and for a first upper intermediate layer (with low index) an adhesive layer. cross-linked and possibly a second intermediate upper layer of thermoplastic (PVB), notably tinted (PVB or EVA). EVA can be a sand-cured thermoset sheet.

[0079] In particular, for the lamination interlayer, at least one first upper intermediate layer is provided, and preferably at most two or at most three upper layers of interlayer and a single lower intermediate layer which is an interlayer layer.

[0080] If the tinted layer is an interlayer layer, for example thermoplastic PVB or EVA, one may prefer at most a single first upper intermediate layer which is preferably an interlayer layer, in crosslinked adhesive for example.

[0081] Films, for example self-supporting films, are preferred for the interlayer layers.

[0082] The interfaces between layers of interlayers, such as foils, are not necessarily discernible. The interlayer may incorporate elements that are not adhesive to the glass, such as functional polymer films or electro-optical elements, sensors, of varying sizes, covering all or part of the glazing. For example, a polymer film such as PET is sandwiched between two thermoplastic foils (PVB, etc.).

[0083] We also prefer to choose a lamination interlayer that is as clear as possible, i.e. with a blur of at most 1.5% and even at most 1%.

[0084] The first holographic layer, particularly in film form, may be in several spaced or joined parts. The first holographic layer may occupy a portion of the surface area separated from the propagation zone of the light beams. The outermost edge may stop before the extinction zone of the guided rays (absorption during propagation), typically 50 cm for extra-clear glass. The width of the holographic layer is preferably at least one centimeter, and for example, at least 10 cm.

[0085] Preferably, between the first functional zone and face F3, the glazed roof comprises one or more lower, transparent, dielectric intermediate layers. These lower intermediate layers are, in particular, interlayer layers. The number of lower intermediate layers is denoted M. Preferably, M is, for example, at most 2 or 1, or even 0. Each lower intermediate layer may have various possible functionalities, but is preferably adhesive, and is clear rather than tinted. Each lower intermediate layer preferably has a submillimeter thickness and is, for example, a film, preferably being at least 30 µm or 50 µm thick.

[0086] One can have one or more lower and / or upper functional chemical barrier layers, for example one or more diffusion barrier layers, for example between the holographic layer and the lower intermediate layer of the interlayer. In this case, the first upper intermediate layer can be this protective layer or be a lower intermediate layer between the holographic layer and another lower intermediate layer such as PVB.

[0087] We wish to avoid any coating that is too reflective, diffusive or absorbent for the upper and lower intermediate layers.

[0088] The single-layer or multi-layer laminate interlayer is in particular of a thickness of at most 1.2 cm or subcentimeter, and is in particular greater than 0.3 mm, in particular all or part thermoplastic (tinted or not), with for example at least a lower part of the interlayer (tinted or not) called lower intermediate layer of interlayer (for example a sheet), of a given thickness preferably of at least 100 µm, in adhesive contact with the face F3.

[0089] The glazed roof is thus tinted, and therefore absorbs visible light, particularly in the spectral range of the light source, to a given thickness, the value of which is, for example, at least 100 pm or at least 300 pm. In particular:

[0090] - the first sheet of glass is tinted, over its entire thickness, by being colored in mass,

[0091] -and / or on all or part of the lamination interlayer, preferably the tinted thickness is submillimeter, for example an upper intermediate layer of interlayer, between face F2 and the lower intermediate layer of interlayer, is tinted, colored in mass, and / or the lower intermediate layer of interlayer is tinted,

[0092] -and / or a transparent tinted film, colored throughout, polymer in particular non-adherent to mineral and / or organic glass, for example with a thickness of at least 30 µm or at least 50 µm and at most 200 µm. The transparent tinted film is inserted between face F2 and the lower intermediate layer of interlayer, for example within the lamination interlayer, between a lower intermediate layer of interlayer and an upper intermediate layer of interlayer.

[0093] For example, the tinted transparent film is a thermoplastic film, preferably flexible and curved to match the curvature of the glazing. The tinted transparent film is, for example: polyester, in particular polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyimide (PI), polyurethane (PU) or cellulose triacetate (TAC), acrylic, polyolefin, in particular polypropylene (PP), polycarbonate (PC) or PMMA, or a (coextruded) PET-PMMA or polyvinyl chloride (PVC) film. With a polymer film made of PC or PMMA, thermoplastic polyurethane (TPU) is preferred as the thermoplastic interlayer for greater chemical compatibility. The same applies if a second sheet of organic glass made of PC or PMMA is chosen; a thermoplastic interlayer layer, in particular a lower intermediate layer, for example thermoplastic polyurethane (TPU).

[0094] As a lower refractive index upper intermediate layer, which is not an interlayer layer, a fluoropolymer film, which is a thermoplastic, can be glued to the F2 face, for example between two interlayer layers formed from PVB or EVA. The fluoropolymer film may be based on or even made of one of the following materials: perfluoroalkoxy PFA, in particular with a ni index of about 1.3, poly(vinylidene fluoride) PVDF, in particular with a ni index of about 1.4, ethylene chlorotrifluoroethylene ECTFE, ethylene tetrafluoroethylene ETFE, more precisely poly(ethylene-co-tetrafluoroethylene, in particular with a ni index of about 1.4, perfluorinated ethylene propylene copolymer FEP or (Fluorinated Ethylene Propylene in English) in particular with a ni index of about 1.3 or polytetrafluoroethylene PTFE in particular with a ni index of about 1.3, polyvinyl fluoride (Polyvinyl Fluoride or PVF).

[0095] An intermediate layer preferably upper or lower according to the invention may be made of crosslinked polymer material in particular an optical adhesive (called OCA for optically clear adhesive in English, LOCA if liquid).

[0096] The advantage of this adhesive layer is the ability to customize the refractive index, and in particular to produce low-index layers without sacrificing transparency. It is therefore particularly sought after as an upper intermediate layer, local layer, or interlayer layer with an index ni.

[0097] For the fabrication of this (intermediate) layer, crosslinkable adhesives can be used that harden when their components react (photocurable, particularly under ultraviolet light, thermocurable, etc.) or when a solvent evaporates. In all cases, a chemical reaction occurs to create chemical bonds for crosslinking; the crosslinked polymer then defines, through the formation of a 3D network, polymer chains linked by chemical bonds.

[0098] Thus, the way in which a curable adhesive hardens depends on its nature. Some (photo)curable adhesives are cured, in particular, by the application of ultraviolet (UVA) or visible (400-405 nm) energy. Others cure at room temperature with the addition of a hardener through a chemical reaction. Still other curable adhesives are cured by a chemical reaction initiated and enhanced by the application of thermal energy.

[0099] Liquid deposition of the crosslinkable adhesive can be done by spraying (from English: spray coating), by curtain coating, by flow coating, by roller coating, by laminar flow through a slot die, by dip coating, by blade coating, by screen printing, by inkjet, by drop casting or by filling a cavity with a syringe in particular.

[0100] Preferably, the crosslinked adhesive layer can be photo-crosslinked by ultraviolet irradiation. The adhesive layer may, for example, comprise a polymer matrix photo-crosslinked by ultraviolet irradiation.

[0101] According to one embodiment, the crosslinked adhesive layer is in particular an adhesive film preferably of a thickness of at least 30pm, and is preferably a pressure-sensitive film, preferably selected from polymers based on acrylate, urethane acrylate or fluorourethane acrylate or silicone or is an adhesive coating preferably of a thickness of at least Ipm.

[0102] According to another embodiment, the crosslinked adhesive layer is a crosslinked polymer-based adhesive film, in particular of at least 30 µm, chosen from a pressure-sensitive film, preferably chosen from polymers based on acrylate, urethane acrylate or fluorourethane acrylate or silicone and a so-called post-adhesive film of partially crosslinked polymer before assembly, and preferably photocrosslinked and based on acrylate.

[0103] In particular for a low refractive index (for ni in particular), the crosslinked polymer material of the crosslinked adhesive layer is for example chosen from polyacrylate-based polymers, in particular urethane acrylate or fluorourethane acrylate or fluorosilicone acrylate, polysiloxanes, silicone, in particular polydimethylsiloxane, epoxy polymer or polyepoxides, polyurethane, polyvinyl acetate, polyester.

[0104] In particular, the crosslinked polymer material of the crosslinked adhesive layer is preferably chosen from an acrylate-based polymer, in particular urethane acrylate or silicone acrylate or silicone-based, and the polymer further having a fluorinated function.

[0105] The following examples of a liquid (UV) curable adhesive for liquid deposition may be cited:

[0106] - acrylate urethane-based adhesive, for example from the company Norland, in particular the product called LOCA Norland NOA 1315, with index ni = 1.315, which is an aliphatic acrylate urethane,

[0107] - fluorourethane acrylate based adhesive, for example from the company Shin-A, in particular the product called SFA 335, with an index neither between 1.335 and 1.339, or SFA 387 with an index neither between 1.385 and 1.389,

[0108] - acrylate-based adhesive, for example, in particular the product known as UZ181A, with index ni =1.47, from the company AKChemTeck, or the product called UVEKOL S15, with index ni =1.44, from the company Allnex.

[0109] Examples include liquid adhesives based on fluorourethane acrylate from the company Shin-A, in particular the product called LOCA Shin-A 335, with an index ni between 1.335 and 1.339 or 387, with an index ni between 1.385 and 1.389.

[0110] Pressure sensitive adhesives (PSA) are commercially available in the form of double-sided adhesive rolls with a liner on each side to protect the PSA film.

[0111] Examples of silicone-based PSAs include Dow Corning® adhesives, Taica adhesives such as OPT alpha GEL® such as K120E, K90E or MRK adhesives such as MR3050, MR3080. Examples of acrylate-based PSAs include Nitto adhesives such as CS98210U, CS98210UK or Tesa® adhesives such as OCA 69206, OCA 69208, OCA 69405.

[0112] The outer edge or edge of the layers may be offset from the clear glass, in particular extending under an internal peripheral masking layer between face F2 and face F3.

[0113] Furthermore, face F4 may comprise an infrared-reflective coating with one or more electroconductive functional layers. Preferably, the coating of face F4 is free of silver and / or gold layers. The electroconductive functional layer may be oxide-based and / or metal nitride-based. The electroconductive functional layer may particularly be based on a transparent conductive oxide or TCO (transparent electroconductive oxide) layer, in particular selected from: fluorine-doped tin oxide, antimony-doped tin oxide and / or indium tin oxide, zinc oxide doped or undoped with aluminum, gallium, or antimony. The TCO electroconductive functional layer is preferably a fluorine-doped tin oxide (SnO2:F) layer or a mixed tin-indium oxide (ITO) layer. In particular, the coating includes a single layer of TCO and even ITO.Other electrically conductive functional layers (TCOs) are possible, including thin films based on mixed indium and zinc oxides (called "IZO"), based on gallium- or aluminum-doped zinc oxide, based on niobium-doped titanium oxide, based on cadmium or zinc stannate, based on antimony-doped tin oxide.

[0114] The infrared-reflecting coating is preferably multilayered, in particular deposited by magnetron sputtering, and comprises a first dielectric sublayer or even a second dielectric sublayer, in particular:

[0115] -based on metal oxide or silicon: zinc and tin oxide, zinc oxide or titanium oxide-based layers, silica

[0116] -based on metal nitride or oxynitride or silicon, in particular based on nitride of one or more elements selected from silicon, aluminium or zirconium, preferably based on silicon nitride,

[0117] -or silicon carbide or silicon oxycarbide.

[0118] The glazing according to the invention may comprise, between face F2 and face F3, an electrically controllable device with a stack formed from the following elements: dielectric support, electrode, active layer, electrode, and in particular a dielectric support for example between two layers of the lamination interlayer, which is formed for example of PVB etc.

[0119] One can choose as an electro-controllable device a device from among a variable blur device and a variable tint device.

[0120] A variable blur device is a liquid crystal optical valve device (SPD for suspended particle device), with a stack formed of the dielectric support, electrode, active layer, electrode, and in particular a dielectric support for example between two sheets of the laminate interlayer formed for example of PVB etc. A variable tint device is an electrochromic device for example.

[0121] The electrically controlled device is, for example, wholly or partly opposite or offset from the guided light extraction means, the extraction means being the first hologram, and / or the second hologram, and / or the third hologram. Furthermore, the electrically controlled device is preferably located between face F2 and the first tinted layer, the first tinted layer being, for example, the upper intermediate layer of a tinted interlayer.

[0122] Between face F3 and the first tinted layer, it is preferable to avoid any layer, of at least lOnm, which is for example an electrode and any layer formed of pure or nitrided metal for example, or even of transparent conductive oxide or even any layer with an extinction coefficient k, k being the imaginary part of the complex refractive index of said layer, of at least 104 or even of at least 102 in the visible, in particular at the reference wavelength for example 550nm and even over the spectral range of the source.

[0123] The glazed roof according to the invention may also include a layer that reflects or absorbs infrared radiation, either on face F2 or on a polymer film, in particular a low-emissivity thin-film stack comprising at least one metallic layer such as silver, where each silver layer is arranged between dielectric layers. In this configuration, the first tinted layer (preferably an interlayer) is closer to face F3 than this low-emissivity stack, and the first sheet of glass is clear, as is any layer, for example an interlayer, between face F3 and the low-emissivity stack.

[0124] More broadly, between the first tinted layer and the F3 face, it is preferable to avoid any layer, of at least lOnm, formed of pure or nitrided metal for example, or even of transparent conductive oxide, having an extinction coefficient k, k being the imaginary part of the complex refractive index, of at least 104 or even of at least 102 in the visible, in particular at the reference wavelength for example 550nm and even over the spectral range of the source.

[0125] It is preferred that the lower and / or upper intermediate layer(s), up to the first tinted layer, have an extinction coefficient k, imaginary part of the complex refractive index, at most 105 or even 107 in the visible, in particular at the reference wavelength for example 550nm and even over the spectral range of the source.

[0126] The lamination interlayer may have a top or tinted layer having a main face FA in adhesive contact with the bare face F2 or with a functional coating on the face F2. The laminated glazing may in fact comprise a layer reflecting or absorbing solar radiation, on face F2, in particular a stack of thin films comprising at least one silver layer, where each silver layer is arranged between dielectric layers.

[0127] The lamination interlayer may have a lower intermediate layer with a main face FB in adhesive contact with the bare face F3 and with the holographic layer.

[0128] In an area close to the injection, the glazing can be masked, with a trim, and / or with a peripheral masking layer.

[0129] In one embodiment, the glazing includes an internal, peripheral, opaque masking layer between face F3 and face F2, in particular an internal masking layer in contact with face F2, in particular defining the clear area of ​​the glass. And / or the glazing may include an internal, peripheral, opaque masking layer on face F4, in particular congruent with or narrower than the width of the internal masking layer.

[0130] The opaque, internal peripheral masking layer is in particular an enamel, black for example, on face F2. It can be an opaque coating on a thermoplastic adhesive layer, in particular an upper intermediate layer of an interlayer, in particular PVB, for example an opaque coating based on PVB and with a coloring agent on a main face of a PVB layer face oriented face F2 or face F3.

[0131] The internal masking layer can be 2 mm or 3 mm thick, and preferably less than 5 mm, from the edge of the glass roof or even up to the edge. The internal masking layer can be a band framing the glass roof, particularly a black band. Opaque material is applied around the entire perimeter of the glass roof to conceal bodywork elements or seals, or to protect adhesive for mounting on the vehicle. The internal masking layer can define the glass area. It can be advantageous for the outer edge of the optical insulation layer to be masked by the internal masking layer, rather than being within the glass area.

[0132] The width of the internal masking layer along the sides of a motor vehicle roof is generally less than that at the front or even the rear.

[0133] For example, for the glass roof, the width of the internal masking layer, and even the interior, along the longitudinal edges of the glass roof, can be up to 30cm and in particular from 10cm to 20cm.

[0134] For example, for the glass roof, the width of the internal, and even interior, masking layer along the rear side edge can be at most 30 cm and in particular at least 1 cm or 5 cm and along the front side edge at most 60 cm in particular at least 1 or 5 cm.

[0135] Preferably, the width of the inner masking layer is greater than that of the inner masking layer.

[0136] The inner, peripheral masking layer may be on the F4 face, specifically facing the inner masking layer, and may even be of the same nature, for example, a black enamel on a second sheet of mineral glass. The inner masking layer may be 2 mm or 3 mm (less than 5 mm) from the edge of the glazing or even right up to the edge.

[0137] The inner masking layer, in particular black, may be a band or even a frame. The inner masking layer may be adjacent to, in contact with, or spaced from an infrared-reflective coating.

[0138] The internal and / or inner masking layer may be an organic or mineral binder, for example fused glass frit, with an organic or inorganic coloring agent, in particular a molecular colorant or an inorganic pigment.

[0139] The internal and / or inner masking layer is preferably a continuous layer (flat with a solid edge or alternatively a gradient edge (set of patterns).

[0140] The thickness of each intermediate layer between face F2 and face F3 is preferably at most 1.5 mm, 1.1 mm, or 0.9 mm, and in particular the thickness of each lamination interlayer is at most 1.1 mm or 0.9 mm. The thickness between face Fl and face F4 is preferably at most 9 mm or 7 mm, particularly for a road vehicle.

[0141] The first sheet of glass is preferably made of mineral glass, possibly tempered, particularly if it is intended to be the outer sheet and if the second sheet is made of organic glass. In particular for vehicle glass roofs, the first (outer) sheet of glass is preferably no more than 2.5 mm thick, or even no more than 2.2 mm – in particular 1.9 mm, 1.8 mm, 1.6 mm and 1.4 mm – and even at least 0.7 mm thick.

[0142] The second sheet of glass can be at least 0.7mm thick, possibly less than that of the first outer sheet of glass, even by no more than 2.2mm - in particular 1.9mm, 1.8mm, 1.6mm and 1.4mm - or even by no more than 1.3mm or by no more than 1mm.

[0143] The total thickness of the first and second sheets of glass is preferably strictly less than 5 or 4mm, even 3.7mm.

[0144] The first and second sheets of glass may be of a size in particular sen possibly identical, for example of general rectangular shape. The first sheet of glass, if exterior, may be larger than the second sheet, if interior, thus exceeding this second sheet on at least part of its perimeter, possibly a second sheet, on the passenger compartment side, smaller with an edge set back in particular by a maximum of 10 or 5cm from the edge of the first sheet of glass, on one or more edges, longitudinal and / or lateral, in particular or all around the perimeter.

[0145] The first sheet can be a clear glass with a functional athermic or even heating coating on the face F2.

[0146] The first mineral glass sheet may be based on silica, soda-lime, preferably silicic soda-lime, or even aluminosilicate, or borosilicate. It may have a total iron oxide content (expressed as Fe2O3) by weight of at least 0.4% and preferably of no more than 1.5%.

[0147] The second mineral glass sheet may be, in particular, based on silica, soda-lime, silicosodocalcium, aluminosilicate, or borosilicate. To limit absorption, it has a total iron oxide content (expressed as Fe2O3) by weight of not more than 0.05% (500 ppm), preferably not more than 0.03% (300 ppm) and not more than 0.015% (150 ppm), and in particular greater than or equal to 0.005%. The redox potential of the second glass sheet is preferably greater than or equal to 0.15.

[0148] In the present text, light transmission is calculated from the transmission spectrum between 380 and 780 nm taking into account illuminant A and the CIE 1964 reference observer (10°).

[0149] The light transmission and tint of each of the glass sheets are adjusted by the chemical composition of the glass and the thickness of the glass sheet. The chemical composition of the glass comprises a colorless base, preferably soda-lime silicate (but other glasses may be used, in particular borosilicate or aluminosilicate glasses), and a coloring component. The coloring component includes, in particular, one or more colorants selected from among the oxides of transition metals—in particular iron oxides (ferrous and ferric), cobalt oxide, chromium oxide, nickel oxide, rare earth oxides, in particular erbium oxide, and selenium.

[0150] The first sheet of tinted glass is a sheet of glass having, for example, a light transmission between 50 and 80%, in particular between 60 and 75%. It comprises a coloring component, for example, consisting of iron oxides, in a total content of between 0.4 and 1.2% by weight, in particular between 0.6 and 1.1% by weight. The resulting glasses are then green, possibly yellow-green or blue-green depending on the proportion of ferrous iron. According to other examples, cobalt oxide, selenium, and / or erbium oxide are added to impart a tint, for example, blue or gray.

[0151] Even better, the first sheet of tinted, over-tinted glass is a sheet of glass having, for example, a light transmission between 5 and 50%, in particular between 8 and 40% and even at most 20%. It comprises a coloring component, for example, consisting of iron oxides, in a total content of between 1.0 and 2.3% by weight, in particular between 1.1 and 2.0% by weight, as well as cobalt and chromium oxides and / or selenium. The coloring component comprises, for example, the following colorants, in the weight contents defined below: Fe2O3 (total iron) from 1.2 to 2.3%, in particular from 1.5 to 2.2%, CoO from 50 to 400 ppm, in particular from 200 to 350 ppm, Se from 0 to 35 ppm, in particular from 10 to 30 ppm. The redox potential is preferably between 0.1 and 0.4, particularly between 0.2 and 0.3. Redox potential is defined as the weight ratio between the ferrous iron content (expressed as FeO) and the total iron content (expressed as Fe2O3). The resulting glasses are typically green or gray.

[0152] The second glass sheet can be made of organic glass, in particular based on polyurethane (PU), polycarbonate (PC), poly(methyl methacrylate) (PMMA), poly(vinyl chloride) (PVC).

[0153] The second organic glass sheet can be flexible to follow the curvature of the first curved sheet or the second organic glass sheet can be pre-formed.

[0154] With an organic glass such as PC or PMMA, thermoplastic polyurethane (TPU) or a cross-linked polymer material is preferred to PVB as a lower interlayer for greater chemical compatibility. Thermoplastic or thermoset EVA can also be chosen.

[0155] In the present invention, the term tempered glass means thermally tempered glass in the absence of any further specification, and preferably tempered glass during a glass bending operation.

[0156] For guiding light beams, the second mineral glass sheet is preferably clear or even extra-clear, or made of clear or even extra-clear organic glass. The second glass sheet has, for example, a light transmission of at least 85%, or even at least 90%. It generally does not contain any coloring matter except for unavoidable impurities, in particular iron oxides, in a total content of between 0.005 and 0.200% by weight, in particular between 0.010 and 0.150% by weight, or even between 0.030 and 0.120% by weight.

[0157] The second pane of glass may (depending on the aesthetic result, the desired optical effect, the intended use of the glazing, etc.) have, for example, a light transmission (LT) greater than or equal to 90% for a thickness of 4 mm, and be formed, for example, from a standard soda-lime glass such as Planilux® from Saint-Gobain Glass, or even extra-clear (for example, TL greater than or equal to 91.5% for a thickness of 4 mm), for example, a soda-lime silicate glass with less than 0.05% Fe III or Fe2O3 such as Diamant® glass from Saint-Gobain Glass, or Optiwhite® from Pilkington, or B270® from Schott, or other composition described in document WO04 / 025334.

[0158] The glass of the first sheet of glass may have undergone a chemical or thermal treatment such as hardening, annealing or tempering (for better mechanical resistance in particular) or bending, and is generally obtained by float process.

[0159] The luminous glazed roof may exhibit a non-zero light transmission, denoted TL, in all or part of the glazed area, generally framed by a masking layer. For the glazed roof, a non-zero light transmission TL is preferred, and even one of at least 0.5%, or at least 2%, and at most 10%, or even at most 8%.

[0160] The second glass sheet can alternatively be made of organic glass (preferably rigid, semi-rigid) such as polymethyl methacrylate (PMMA)- preferably with lamination interlayer (PU)-, polycarbonate (PC)- preferably with lamination interlayer PVB-.

[0161] In particular, the following stacking arrangements can be chosen for the stacking: first sheet of glass, laminating interlayer, second sheet of glass:

[0162] -mineral glass, PVB (acoustic for example), mineral glass.

[0163] - mineral glass, lamination interlayer, polycarbonate,

[0164] For better thermal insulation, the first sheet of glass, or other layer, is tinted and preferably over-tinted,

[0165] The light transmission and tint of each of the glass sheets are adjusted by the chemical composition of the glass and the thickness of the glass sheet. The chemical composition of the glass includes a colorless base, preferably soda-lime silicate, but other glasses may be used, in particular borosilicate or aluminosilicate glasses, as well as a coloring component. The coloring component includes, in particular, one or more colorants selected from among the oxides of transition metals—in particular iron, ferrous and ferric oxides, cobalt oxide, chromium oxide, nickel oxide, rare earth oxides, in particular erbium oxide, and selenium.

[0166] The first sheet of tinted glass is a sheet of glass having, for example, a light transmission between 50 and 80%, in particular between 60 and 75%. It comprises a coloring component, for example, consisting of iron oxides, in a total content of between 0.4 and 1.2% by weight, in particular between 0.6 and 1.1% by weight. The resulting glass is then green, possibly yellow-green or blue-green depending on the proportion of ferrous iron. According to other examples, cobalt oxide, selenium, and / or erbium oxide are added to impart a tint, for example, blue or gray.

[0167] The light rays received by the glazed roof are emitted by a light source, preferably contained within the glazed roof, emitting a beam of light in the visible spectrum. The light source is, for example, an array of light-emitting diodes. placed on a first printed circuit board support (such as a PCB for "printed circuit board" in English), in particular a strip, or even a light source which includes an optical extraction fiber coupled with a primary light source, for example one or more light-emitting diodes.

[0168] Light-emitting diodes (LEDs) can be pre-assembled on one or more PCBs or on substrates with power supply traces. The PCBs can be attached to other substrates, such as profiles. The PCB is generally thin, typically 3 mm or less thick, or even 1 mm, 0.1 mm, or, where applicable, thinner than the thickness of a laminate interlayer. Several PCBs can be used, particularly if the areas to be illuminated are widely separated. The PCB can be made of a flexible, dielectric, or electroconductive material (metallic, such as aluminum, etc.), a composite material, a plastic material, etc.

[0169] The light source may be removable, added, sold separately from the glazing, or as a kit. Preferably, the light source is peripheral, preferably offset from the clear glass.

[0170] According to one embodiment, the light source is monochromatic and emits a light beam comprising electromagnetic waves in the spectrum in a range centered around wavelength XI with a spectral bandwidth of 60 nm. Thus, the emitted light beam has a wavelength X1 + 30 nm, with X1 + 30 nm chosen from LB1 = 532 nm ± 30, LB2 = 480 nm ± 30, and LB3 = 680 nm ± 30. In particular, LB1 corresponds to the color green, LB2 corresponds to the color blue, and LB3 corresponds to the color red.

[0171] According to another embodiment, the light source is polychromatic and emits a light beam with wavelengths of the first wavelength XI, the second wavelength X2, and the third wavelength X3. The wavelength XI is chosen from LB1 = 532 nm ± 30 nm (green), LB2 = 480 nm ± 30 nm (blue), or LB3 = 680 nm ± 30 nm (red). The wavelength X2 is distinct from XI and is chosen from LB1 = 532 nm ± 30 nm (green), LB2 = 480 nm ± 30 nm (blue), or LB3 = 680 nm ± 30 nm (red). The wavelength X3 is distinct from XI and is chosen from LB1 = 532 nm ± 30 nm (green), LB2 = 480 nm ± 30 nm (blue), or LB3 = 680 nm ± 30 nm (red). In particular, for all indices of the non-holographic layers, preferably the conditions on the indices are also true for X2 and X3.

[0172] Preferably, the light source is located on a part of the glazing located inside the trim of the vehicle, the essential function of which is to keep it out of sight of the vehicle's passengers and to protect the modules from dust and external aggressions.

[0173] It is also known, notably from document WO 2013 / 110885, to drill a hole in the glass sheet and place the diodes in it. This hole is made close to the means The extraction process is specifically designed to shorten the optical path traveled by the light between the diodes and the extraction device. This reduces losses due to light absorption. The light emitted by the diodes is injected into the glass sheet through an additional slice formed by the hole. The light then reflects between the two main surfaces of the glass sheet until it reaches the extraction device. The illuminated area is located inside the passenger compartment, in the case of a roof, or to display signals or information for the driver or any other passenger.

[0174] The glazing may include several light sources, in particular light-emitting diodes. Naturally, several light sources (one or more series of diodes) may be coupled to the second pane.

[0175] Another aspect of the invention relates to a vehicle comprising a glass roof according to any one of the preceding claims.

[0176] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0177] The figures are presented for illustrative purposes only and are not intended to limit the invention.

[0178] The [Fig.l], [Fig.l'], [Fig.2], [Fig.3], [Fig.4], [Fig.5], [Fig.7], [Fig.8], [Fig.9], [Fig.9'] , [Fig.10], [Fig.10'], [Fig.11] are embodiments of the glazed roof,

[0179] Figure 12 is a representation of the process of etching a hologram of a microlens array,

[0180] Fig. 13 is a representation of an off-axis Fresnel zone,

[0181] The [Fig.14] is a figure representing the intrinsic diffraction efficiency of the hologram of a glass roof, according to the observation direction 0° and the [Fig. 14'] is a labeled diagram of the [Fig. 14] in black and white.

[0182] The [Fig. 15] is a figure representing the intrinsic diffraction efficiency of the hologram of the same glazed roof as the [Fig. 14], according to the observation direction +30° and the [Fig. 15'] is a labeled diagram of the [Fig. 15] in black and white.

[0183] The [Fig. 16] is a figure representing the intrinsic diffraction efficiency of the hologram of the same glazed roof as the [Fig. 14], according to the observation direction -30° and the [Fig. 16'] is a labeled diagram of the [Fig. 16] in black and white.

[0184] Fig. lôbis represents the angular acceptance and spectral acceptance of a Fresnel zone,

[0185] The [Fig. 17] is a figure representing the intrinsic diffraction efficiency of the hologram of a glazed roof, according to the observation direction +30° and the [Fig. 17'] is a labeled diagram of the [Fig. 17] in black and white.

[0186] The [Fig. 18] is a figure representing the intrinsic diffraction efficiency of the hologram of a glass roof, according to the observation direction -30° and the [Fig. 18'] is a labeled diagram of the [Fig. 18] in black and white. DETAILED DESCRIPTION

[0187] The figures are shown for illustrative purposes only and are not intended to limit the invention. In the following text, the same reference numeral in different figures represents the same object. The figures are not to scale.

[0188] Figure 1 is an embodiment of the glazed roof 100, comprising the first tinted glass sheet 1, having the main face Fl 11 facing outwards and the opposite main face F2 12, and the second glass sheet 2, having the opposite face F3 13 and face F4 14, F4 facing inwards. The first glass sheet 1 comprises the edge 10 and the opposite edge 10', and the second glass sheet comprises the edge 20, on the same side as edge 10, and the opposite edge 20', on the same side as edge 10. The glazed roof 100 includes a masking layer 7 on the face F2 12, such as a black enamel or ink. In particular, the inner contour of the masking layer 7 defines the clear glass 15.

[0189] With reference to [Fig. 1], the glazed roof 100 further includes the holographic layer 6 comprising the first functional zone 60, the lower intermediate layer 32, the upper intermediate layer 31 and the upper intermediate layer 33. The glazed roof 100 further includes a light source 4 emitting light rays at an angle 0, for example, the light injection being carried out in this embodiment by the slice 20.

[0190] In particular, n2 is the lowest refractive index at XI in the visible among the refractive indices of the upper intermediate layer(s) 31, 33, in particular intercalary, between the first excluded holographic layer 6 and up to the first included tinted layer.

[0191] In the absence of a tinted upper intermediate layer or in the absence of an upper intermediate layer, n2 is equal to nv.

[0192] Furthermore, ni is the lowest refractive index at XI among the refractive indices of the possible lower intermediate layer(s) (in this case, for example, the lower intermediate layer 32), of the first functional zone, and n0, with n2 strictly less than nL.

[0193] In this embodiment, the upper intermediate layer 31 is made of OC A, and the lower intermediate layer 32 is made of PVB. In addition, the first glass sheet 1 is tinted. In particular, in this embodiment, nu is the refractive index of the lower intermediate layer 32, n2 is the refractive index of the upper intermediate layer 31, and n2 is the refractive index of the upper intermediate layer 33. Thus, in this embodiment, ni is equal to the minimum refractive index between nu, nm and n0. Furthermore, in this embodiment, n2 is equal to the minimum refractive index between n2i, n22 and nv.

[0194] The roof 100 is adapted to receive a beam of light in the second glass sheet 2, from light rays injected at XI into the second glass sheet 2, with a range 01 of angles of incidence in the second glass sheet 2. Said light rays are guided in the roof until they reach the first hologram of the first functional zone 60. In particular, the range 01 of angles is such that arcsin (n2 / n0) < 01 <arcsin (ni / n0).

[0195] The optical function of said first hologram is chosen such that a portion of the rays guided in the roof reaches the first hologram and is diffracted and extracted from the roof on the side of face F4 14, the diffracted rays being defined by a range of angles of incidence 02 at face F4 14, the range of angle 02 being between -arcsin ( l / n0) and arcsin ( l / n0).

[0196] Fig. l' is a top view of the glazed roof 100 according to Fig. l.

[0197] The [Fig.2] is a glazed roof 200 which differs from the roof 100 in that the inter layer The upper median 31 of the glazed roof 200 is tinted. The glazed roof 200 also includes a layer reflecting or absorbing infrared radiation 16 on face F2 12.

[0198] Figure 3 is an embodiment of the glazed roof 300 which differs from the roof 100 in that the upper intermediate layer 33 of the glazed roof 300 is made of tinted PVB and the upper intermediate layer 31 is clear. In addition, the glazed roof 300 includes a second masking layer 8 on the face F4 14 of the second glass sheet 2.

[0199] The glazed roof 300 further includes a second light source 4' emitting light rays, the light injection being carried out in this embodiment by the slice 20'.

[0200] The holographic layer 6 does not cover the entire surface of the glazed roof, and the space 31' not filled by the holographic layer 6 is filled by thinning the upper intermediate layer 31. The thinning is sufficient or insufficient depending on the thickness of the holographic layer 6. The space 31' filled by thinning, for example, or by adding material (PVB frame, for example), does not affect the determination of the index n2 or the index nh

[0201] Figure 4 is an embodiment of the glazed roof 400. It differs from the glazed roof 100 in that the first sheet of glass 1 is colorless; the upper intermediate layer 31 is tinted. The holographic layer 6 is a coating on the face F3 13 or even on the upper layer 31.

[0202] The glazed roof 400 further includes an infrared-absorbing layer 15 on the F4 face 14 of the second sheet of glass.

[0203] The glazed roof 400 further comprises the assembly 4 of one or more light sources emitting light rays at an angle 0, for example, light injection being carried out in this embodiment by tranche 20.

[0204] The [Fig.5] is an embodiment of the glazed roof 500 which differs from the glazed roof 100 in that it includes an infrared-absorbing layer 15' on the face F2 12 of the first sheet of glass and in that the upper intermediate layer 31 is tinted.

[0205] The [Fig.6] is an embodiment of the glazed roof 600 which differs from the glazed roof 100 in that the upper intermediate layer 33 is tinted, and in that it includes the infrared reflective or absorbing layer 15 on the face F4 14 of the second glass sheet 2 and the infrared reflective or absorbing layer 15' on the face F2 12 of the first glass sheet 1.

[0206] With reference to [Fig.6], the upper intermediate layer 33 is for example made of PVB, the upper intermediate layer 31 is made of OCA.

[0207] The glazed roof 600 further includes the light source 4, the light injection being carried out in this embodiment by the slice 20 of the second sheet of glass 2 and the second light source 4', the light injection being carried out by the slice 20' of the second sheet of glass 2.

[0208] The [Fig.7] is an embodiment of the glazed roof 700 which differs from the embodiment of the glazed roof 100 in that it does not include the upper intermediate layer 31 or the upper intermediate layer 33, and in that the holographic layer which is formed, in this embodiment, of a first part 6 and a second part 6'.

[0209] With reference to [Fig. 7], the first part 6 is deposited on the lower intermediate layer 32 and includes a portion 60 of the first functional zone. The second part 6' is deposited on a lower intermediate layer 32' and includes a second portion 60' of the first functional zone. In particular, the portions of the holographic layer, the lower intermediate layer 32, and the lower intermediate layer 32' do not extend over the entire surface of the glazed roof 700, and the space 32" not filled by these layers is filled, for example, by finishing or adding material.

[0210] Figure 8 is an embodiment of the glazed roof 800 which differs from the glazed roof 100 in that the upper intermediate layer 31 comprises a first part 6 and a second part 6' of the holographic layer. The first part 6 of the holographic layer comprises a first part 60 of the functional area, and the second part 6' of the holographic layer comprises a second part 60' of the functional area.

[0211] The glazed roof 800 further comprises the lower intermediate layer 32 below the first part 6 of the holographic layer and the lower intermediate layer 32' below the second part 6' of the holographic layer, layers 32 and 32' being surrounded by an intermediate 32" layer deposited by milling for example.

[0212] In particular, the upper intermediate layer 33 is in clear OCA for example.

[0213] The glazed roof 800 further comprises layer 15 which reflects or absorbs light frarouges, on face F4 14 of the second sheet of glass 2.

[0214] Fig. 9 is a representation of the glazed roof 900 which differs from the glazed roof 600, shown in Fig. 6, in that it does not include the second light source 4' and in that the light source 4 is embedded within the second sheet of glass 2 and in particular via one or more holes 18 made in said sheet of glass 2 and each closed by a metal disc 50.

[0215] The [Fig.9'] represents the glazed roof 900 of the [Fig.9] according to a top view.

[0216] The [Fig. 10] is an embodiment of the glazed roof 1000 which differs from the previous roof 900 according to [Fig. 9], with the addition of a light redirecting element 9 located in the lower intermediate layer 32. In this embodiment, the injection of light from the light source 4 into the second glass sheet 2 is carried out by the light redirecting element 9 on the F3 face side (or F4 face according to an embodiment not shown, the light source then being opposite or offset from the F4 face). The optical coupling is in particular direct or achieved via an optical system, in particular with the light source and the light redirecting element offset by a clear glass area, facing an internal masking layer 7. In particular, the light redirecting element is, for example, a prismatic film.

[0217] The [Fig. 10'] is a top view of the glazed roof 1000 according to the embodiment of [Fig. 10],

[0218] According to another embodiment, the injection of light from the light source in optical coupling with the second sheet is for example carried out by a wall delimiting a closed hole in the second sheet of glass, in particular a hole offset by a clear pane, facing an internal masking layer on the face F2 or on an interlayer layer (PVB for example).

[0219] Fig. 11 is a glazed roof 1100 which is a variant embodiment of the glazed roof 100 of Fig. 1. In this embodiment, a first 6, a second 6' and a third 6" holographic layers are intercalated between the upper intermediate layer 31 and the lower intermediate layer 32. In particular, between the first holographic layer 6 and the second holographic layer 6' is intercalated an adhesive tape 34, and between the second holographic layer 6' and the third holographic layer 6".

[0220] The first holographic layer 6 comprises the first functional area 60, the second holographic layer 6' comprises the second functional area 61 and the third holographic layer 6" comprises the third holographic layer 62.

[0221] According to one embodiment, each functional area comprises a hologram in volume.

[0222] Regarding the first hologram of the first holographic layer, the optical function of said first hologram is chosen such that a portion of the rays guided in the roof, in the range 01, reaches the first hologram and is diffracted and extracted from the roof on the side of the face F4 of the glazed roof.

[0223] Preferably, the first hologram is a diffraction grating, preferably sinusoidal. The diffraction grating is preferably a constant-pitch diffraction grating or a variable-pitch diffraction grating.

[0224] For example, the first hologram is a set of off-axis Fresnel zones, notably obtained from a microlens array and in particular obtained from the recording of the field transmitted by a microlens array (or matrix). Indeed, the hologram of a microlens is a Fresnel zone. In this example, the first hologram thus comprises a plurality of elementary holograms, each elementary hologram being obtained from a microlens and corresponding to a Fresnel zone. The use of the hologram of a microlens array is advantageous because, to obtain homogeneous illumination when observing the roof in a given direction, and in particular at 0°, it is necessary to extract the rays within a cone, which is advantageously achieved by a microlens array or, equivalently, by an array of Fresnel zones.

[0225] The [Fig. 12] is a figure representing the recording of a hologram from of a 1001 microlens matrix.

[0226] In the recording process, an assembly 102 consisting of a glass substrate on which a holographic material is fixed is used.

[0227] In particular, the assembly 1021 is facing the convex part of each microlens of the microlens array 1001.

[0228] During the recording of a hologram, a planar signal beam 1031 illuminates the planar side of the microlens array 100' which generates a set of spherical waves 1041 from the convex side of the microlens array 100'.

[0229] In addition, a reference beam 1011 comprising plane waves illuminates the convex face of each microlens of the microlens array 1001. The reference beam 1011 is inclined at an angle 0' with respect to the normal to the assembly 1021.

[0230] The holographic material of the assembly 1021 records the interferences between the set of spherical waves 104 generated by the microlens array 1001 and the reference beam 101, the interference pattern obtained being a set of Fresnel zones, each Fresnel zone corresponding to a microlens.

[0231] Fig. 13 is an example of an off-axis Fresnel zone, also called a "zone "Plate" in English.

[0232] In particular, according to the preceding description of the recording of a hologram of a microlens, a Fresnel zone, denoted Z, can be modeled by the addition of a spherical wave S and an inclined plane wave P.

[0233] Thus, the Fresnel zone is defined by the following formula: Z = S + P, where S and P are two optical fields, with S = S0 * gi^œ+^+y and P = PO ■ In particular, S0 being a multiplicative factor of the same unit as S, and PO being a multiplicative factor of the same unit as P.

[0234] With R the distance between the point source and the hologram and 0' the reference ground angle with respect to the optical axis.

[0235] Fresnel zones can be considered as networks whose period (or step) varies continuously. Thus, each Fresnel zone comprises a low frequency (LF) side and a high frequency (HF) side represented in [Fig. 13].

[0236] As previously stated, the rays diffracted and extracted from the roof by the first hologram are defined by a range of angles of incidence θ2 at face F4, θ2 being less than θ1, and defined such that between -arcsin(l / n0) < θ2 < arcsin(l / n0). In particular, the value 1 in the formula arcsin(l / n0) represents the refractive index of air.

[0237] The optical function of said first hologram is further chosen such that, among the light rays diffracted by the hologram, more than 10% of the rays are diffracted according to the angle of incidence range 02, or even more than 50%, or even 70%.

[0238] When the guided angular domain in the hologram is restricted, several bounces are required before each point of the hologram can see multiple guided angles. For a monochromatic beam, the different areas receiving light do not overlap. Thus, the light is extracted disjointly until continuous light is obtained. Continuous light extraction is achieved after k bounces, where k is greater than or equal to 1. The number k bounces is determined from a distance hk from one end of the holographic layer to the edge of the glass roof, with hk greater than or equal to (2k + 1) *^*(1311^] - with d the thickness traversed by the light from Its injection into the second glass sheet and down to the layer with index n2. For example, d can be equal to the thickness of the second glass sheet, the lower intermediate layers (if applicable), and the holographic layer. Furthermore, θ is the angle of a first guided ray, and 0k2 is the angle of a second guided ray.

[0239] According to the embodiment in which the light source is polychromatic, the first so-called multiband hologram also diffracts at the second wavelength X2, the first functional zone having a refractive index nH2 at / .2 or even diffracts also at the third wavelength X3, the first functional zone having a refractive index nH3 at X3 or in that the roof includes a second hologram diffracting at / .2 between the first hologram and the face F3.

[0240] Optionally, the glass roof includes a second holographic layer having a second functional zone having a refractive index nH2 at X2 and possibly the roof includes a third diffracting hologram at X3, between the second hologram and the face F3, with a third holographic layer with a third functional zone having a refractive index nH3 at / .2.

[0241] In other words, the holographic layer comprises either a holographic layer comprising a multiband hologram diffracting at XI, X2, X3 or the roof comprises second and third holograms diffracting respectively at X2, X3 and X0 is in a spectral band (in particular LB2) including the middle value among XI, X2, X3, and the second and third holograms have distinct inscription wavelengths in the visible X'O and X'0, distinct from X0 in a spectral band including a distinct middle value among XI, X2, X3 (in particular LB1 and LB3).

[0242] When the second functional area is identical to the first functional area, the first and second holograms are multiplexed, resulting in a linear combination of the optical function of the first hologram and the optical function of the second hologram. The first hologram can alternatively diffract over two distinct wavelength ranges.

[0243] In particular, n2a denotes the refractive index, the lowest at X2 in the visible:

[0244] a) In the case of a second functional zone, among the refractive indices at X2 of the lower intermediate layer(s) above (going towards face F2) the second functional zone, the first functional zone, the upper intermediate layer(s) and up to and including the first tinted layer,

[0245] b) or in the case of a first multiband hologram, among the refractive indices of the upper intermediate layer(s) (in particular the interlayer) between the first excluded holographic layer and up to the first included tinted layer

[0246] c) or in the absence of a tinted upper intermediate layer or upper intermediate layer, n2a being equal to nva with nva the X2 refractive index in the visible of the first sheet

[0247] i) nu is the lowest refractive index at X2 among the refractive indices of the possible lower intermediate layer(s) below the second functional zone (towards face F3), the index nH2 of the second functional zone, and nOa which is the refractive index at X2 in the visible of the second glass sheet.

[0248] j) or in the case of a first multiband hologram, nu is the lowest refractive index at X2 among the refractive indices of the possible lower intermediate layer(s) (below the first functional zone), the index nH2 of the first functional zone, and nOa which is the refractive index at X2 in the visible of the second sheet

[0249] The optical function of said second hologram or of the first hologram mul tibandes is chosen such that a portion of light rays injected at / .2 into the second glass sheet, guided into the roof, in particular in the range 01, reaches the second hologram or the first multiband hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of angles of incidence 02 in face F4, therefore in the second glass sheet, and between -arcsin (l / nOa) and arcsin (l / nOa).

[0250] Optionally, n2b is defined as the lowest refractive index at / .3 in the visible range:

[0251] a) in the case of a third functional zone, among the X3 refractive indices of the or lower intermediate layers above (going towards face F2) the third functional zone (including the second functional zone), the first functional zone, the upper intermediate layer(s) and up to and including the first tinted layer,

[0252] b) or in the case of a first multiband hologram, among the refractive indices of the upper intermediate layer(s) (in particular, the interlayer), between the first excluded holographic layer and up to the first included tinted layer

[0253] c) or in the absence of a tinted upper intermediate layer or upper intermediate layer, n2b being equal to nvb with nvb the refractive index of / .3 in the visible of the first sheet

[0254] In particular, n[b is the lowest refractive index at X3 among the refractive indices of the possible lower intermediate layer(s) below the third functional zone (towards the F3 face), the index nH3 of the third functional zone, and n Ob which is the refractive index at / .3 in the visible of the second sheet.

[0255] In particular, the optical function of said third hologram or of the first multiband hologram being chosen such that a portion of light rays injected at X3 into the second glass sheet, guided into the roof, in particular in the range 01, reaches the third hologram or the first multiband hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of angles of incidence 02 in face F4, in the second glass sheet, and between -arcsin (l / nOb) and arcsin (l / nOb).

[0256] According to the preceding embodiment, for a given observation direction in the range 02:

[0257] -the first hologram diffracts at XI and has a maximum diffraction efficiency in a first subrange of 01a with a width of at least 1°,

[0258] - the second hologram or the first multiband hologram diffracting at X2 has a maximum diffraction efficiency in a second sub-range of 01b with a width of at least 1° with partial or disjoint overlap of 01a

[0259] -the possible third hologram or the first multiband hologram (or even the second multiband hologram), diffracting at X3, having a diffraction efficiency of maximum fraction in a third sub-range of 01c with a width of at least 1° with partial or disjoint overlap with first and second sub-ranges 01a and 02a. In particular, the set of sub-ranges 01a, 01b, 01c preferably covers at least 60%, 80% of 01.

[0260] In addition, nu is the lowest refractive index at / .2 among the refractive indices of the possible lower intermediate layer(s), the first functional zone and nOa.

[0261] The third functional zone may be distinct from the first functional zone and distinct from the second functional zone or identical to the first functional zone and identical to the second functional zone.

[0262] When the third functional area is distinct from the first functional area and the second functional area, the first hologram, the second hologram and the third hologram are stacked, the third hologram being in a lower intermediate layer comprising said third functional area.

[0263] When the third functional area is identical to the first functional area and the second functional area, the first hologram, the second hologram and the third hologram are multiplexed, resulting in a linear combination of the optical function of the first hologram, the optical function of the second hologram and the optical function of the third hologram.

[0264] In particular, the optical function of said third hologram being chosen such that a portion of the rays guided in the roof, in the range 01, reaches the third hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of angles of incidence 02 in face F4.

[0265] In particular the maximum difference between the refractive indices nHb nH2, nH3 for LB1, LB2 and LB3 is at most 0.2 and even 0.1.

[0266] Consider an embodiment in which the glazed roof (not shown) comprises the first sheet of tinted glass, the second sheet of glass with index n0 = 1.52, the holographic photopolymer layer and the first upper intermediate layer of PVB with refractive index n2i = 1.485

[0267] In this embodiment, the first hologram of the holographic layer is made from a microlens matrix and therefore corresponds to a set of off-axis Fresnel zones.

[0268] In particular, the holographic layer has the following indices: nHi = 1.481 for XI = LB3, which corresponds to red, nH2 = 1.491 for / .2 = LB1, which corresponds to green and n hs = 1.497 for X3 = LB2, which corresponds to blue.

[0269] Figs. 14, 14', 15, 15', 16, 16', 17, 17' and 18, 18' each represent the intrinsic diffraction efficiency of The first hologram of the glazed roof is shown for several embodiments and observation directions, where the ordinates represent the wavelength X of the light rays in the glazing, X being in nanometers, and the abscissas represent the angle A of the rays in the glazed roof, A being in degrees. The intrinsic efficiency is between 0 and 1.

[0270] Figure 14 represents the intrinsic diffraction efficiency of the first hologram of the glazed roof of the preceding embodiment as a function of the wavelength and angles of the rays guided in the glazed roof, for an observation direction of 0°. Figure 14' represents Figure 14 in black and white with a legend.

[0271] Light rays of wavelength XI = LB3 are not guided by the roof.

[0272] In particular, guided light rays of wavelength X2 = LB1 (green) have an angle of incidence in the second glass sheet between 75° and 77.7°. For this wavelength, continuous light extraction is obtained from n = 5 reflections of the guided rays, from a distance h5 = 4.8 cm.

[0273] Furthermore, the guided light rays of wavelength X3 = LB2 (blue) have an angle of incidence in the second glass sheet between 77.6° and 77.7°. For this wavelength, continuous light extraction is obtained from n = 2 reflections of the guided rays, from a length h2 = 1.9 cm of the holographic layer.

[0274] With reference to [Fig. 14], for white light, the hologram only extracts guided rays with a wavelength between approximately 480 and 580 nm.

[0275] With reference to [Fig. 14], for incident rays with wavelength X2 = LB1 = 532 nm, said first hologram has a theoretical diffraction efficiency of 1, or equivalently 100% for all guided angles, in the observation direction at 02 = 0°. In other words, for a light beam with a wavelength of 532 nm, all guided angles are extracted via face F4. Furthermore, for guided rays with a wavelength between 530 nm and 540 nm, all guided angles are extracted by the first hologram.

[0276] With reference to [Fig. 14], when the first hologram diffracts selectively at X3=LB2 = 480 nm, said hologram has a diffraction efficiency greater than or equal to 0.8, in the observation direction at 02 = 0° for guided angles whose angle of incidence is between 77.6° and 77.7°.

[0277] Figure 15 shows the intrinsic diffraction efficiency of the first roof hologram described in the preceding embodiment, in an observation direction at 02 = +30°, which corresponds to the guided rays diffracted by the spatial low-frequency side of the Fresnel zones, presented previously. Figure 15' represents Figure 15 in black and white with a legend.

[0278] With reference to [Fig. 15], for incident rays of wavelength X2=LB1 = At 532 nm, the first hologram has a diffraction efficiency of 1, or equivalently 100% for all guided angles, in the observation direction at 02 = +30°. In other words, for a light beam with a wavelength of 532 nm, all guided angles are extracted via face F4. Furthermore, for guided rays with a wavelength between 525 nm and 555 nm, all guided angles are extracted by the first hologram.

[0279] With reference to [Fig. 15], when the first hologram diffracts selectively at X3=LB2 = 480 nm, said hologram has a theoretical diffraction efficiency greater than or equal to 0.8, in the observation direction at 02 = +30° for guided angles whose angle of incidence is between 77.2° and 77.7°.

[0280] Figure 16 shows the intrinsic diffraction efficiency of the first roof hologram described in the preceding embodiment, in an observation direction at 02 = -30°, which corresponds to the guided rays diffracted by the high spatial frequency side of the Fresnel zones, presented previously. Figure 16' shows Figure 16 in black and white with a legend.

[0281] With reference to [Fig. 16], for incident rays of wavelength X2 = LB1 = 532 nm, said first hologram has a diffraction efficiency of 1, or equivalently 100% for all guided angles, in the observation direction at 02 = -30°. In other words, for a light beam with a wavelength of 532 nm, all guided angles are extracted via face F4. Furthermore, for guided rays with a wavelength between 530 nm and 552 nm, all guided angles are extracted by the first hologram.

[0282] Thus, the spectral width over which all guided angles are extracted is less than approximately 15 nm. Outside this spectral band, the diffraction efficiency is between 0 and 0.1.

[0283] With reference to [Fig. 15] and [Fig. 16], rays diffracted by the low-frequency side of the Fresnel zones result in a wider spectral coverage and a lower angular coverage, and rays diffracted by the high-frequency side of the Fresnel zones result in a lower spectral coverage and a wider angular coverage.

[0284] Fig. lôbis represents the diffraction on the low frequency side BF and the diffraction on the high frequency side ZF of a Fresnel zone and their spectral covers, as described in the preceding paragraph.

[0285] Consider a second embodiment in which the glazed roof (not shown) comprises the first tinted glass sheet, the second glass sheet with index n0 = 1.52, the holographic photopolymer layer and the first upper intermediate layer of OCA with refractive index n2i = 1.3

[0286] In this second embodiment, the first hologram of the holo layer The graph is made from a microlens matrix and therefore corresponds to a set of off-axis Fresnel zones.

[0287] In particular, the holographic layer has an index modulation, with nm = 1.481 for XI = LB3, which corresponds to red, nH2 = 1.491 for X2 = LB1, which corresponds to green and nH3 = 1.497 for X3 = LB2, which corresponds to blue.

[0288] Figure 17 shows the intrinsic diffraction efficiency of the first roof hologram mentioned in the second embodiment, in an observation direction at 02 = +30°, which corresponds to the guided rays diffracted by the spatial low-frequency side of the Fresnel zones, presented previously. Figure 17' shows Figure 17 in black and white with a legend.

[0289] With reference to [Fig. 17] for incident rays of wavelength X2=LB 1 = 532 nm, said first hologram has a theoretical intrinsic diffraction efficiency equal to 1, or equivalently to 100% for guided angles with an incident angle between approximately 67.5° and 71.8°, in the observation direction at 02 = +30°.

[0290] With reference to [Fig. 17], when the first hologram diffracts selectively at X3=LB2 = 480 nm, said hologram has a theoretical intrinsic diffraction efficiency equal to 1, in the observation direction at 02 = +30° for guided rays whose angle of incidence is between approximately 70.5° and 73.6°.

[0291] With reference to [Fig. 17], when the first hologram diffracts selectively at XI=620 nm, said hologram has a theoretical intrinsic diffraction efficiency equal to 1, in the observation direction 02 = +30° for guided rays whose angle of incidence is between approximately 51.9° and 61.6°.

[0292] Figure 18 shows the intrinsic diffraction efficiency of the first roof hologram described in the second embodiment, in an observation direction at 02 = -30°, which corresponds to the guided rays diffracted by the high spatial frequency side of the Fresnel zones, presented previously. Figure 18' shows Figure 18 in black and white with a legend.

[0293] With reference to [Fig. 18], for incident rays of wavelength X2=LB1 = 532 nm, said first hologram has a theoretical intrinsic diffraction efficiency equal to 1, or equivalently to 100% for guided angles with an incident angle between approximately 63.6° and 68.9°, in the observation direction at 02 = -30°.

[0294] With reference to [Fig. 18], virtually no red or blue rays are diffracted, the diffraction efficiency being less than 0.05.

[0295] Figures 14 and 18 together illustrate the feasibility ranges for obtaining an effective hologram at one or more wavelengths

Claims

Demands

1. Vehicle laminated glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) comprising: - a first sheet (1) of mineral glass, called the outer sheet, transparent, having a first principal face (11) called face Fl and a second principal face (12) called the opposite face F2, with a refractive index nv at a first wavelength XI in the visible range, preferably greater than or equal to 1.5 - a second internal glass sheet (2), made of organic or mineral glass, transparent, with a refractive index of n0 to XI, having a principal face (13) called face F3 and an opposite principal face (14) called face F4, - between face F2 and face F3, a dielectric laminated interlayer made of polymer material, comprising at least one layer of laminated interlayer, the glazed roof comprising, between face F2 and F3, in this order moving away from F2: - preferably one or more upper intermediate dielectric layers (31, 33), transparent, with given refractive indices in the visible range, the first sheet (1) being tinted and / or among the upper intermediate layer(s) (31, 33) a first layer being tinted, when several upper intermediate layers are tinted, the first tinted layer is the tinted layer closest to face F3, - a first holographic layer (6), transparent, dielectric, comprising a first functional zone (60) with a first volume hologram, diffracting at XI, the first functional zone having a refractive index nHi at XI - preferably, between the first functional zone and the F3 face, one or more lower intermediate layers (32), transparent, dielectric, n2 being the lowest refractive index at XI in the visible: a) among the refractive indices of the upper intermediate layer(s) (31, 33), in particular the intercalary layer, between the excluded first holographic layer (6) and up to and including the first tinted layer b) or in the absence of an upper tinted intermediate layer or in the absence of an upper intermediate layer n2 being equal to nv ni being the lowest refractive index at XI among the refractive indices of the possible lower intermediate layer(s), of the first functional zone and n0, with n2 <ni le toit étant adapté pour recevoir un faisceau lumineux dans la deuxième feuille de verre, de rayons lumineux injectés à XI dans la deuxième feuille de verre, avec une gamme 01 d’angles d'incidence dans la deuxième feuille de verre,being guided through the roof until reaching the first hologram and with 01 such that arcsin (n2 / n0) <01 <arcsin (ni / n0) la fonction optique dudit premier hologramme étant choisie telle qu’une portion des rayons guidés dans le toit atteint le premier hologramme et sont diffractés et extrait du toit du côté de la face F4, rayons diffractés définis par une gamme d’angles d'incidence 02 en face F4 , et comprise entre -arcsin (l / n0) et arcsin (l / n0).,

2. Glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to the preceding claim characterized in that the first hologram is in reflection.

3. Glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that the first holographic layer is a coating, preferably on the F3 face, or the first holographic layer is a film.

4. Glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that at least one lower intermediate layer (32) is an adhesive layer in contact with the first holographic layer and / or at least one upper intermediate layer (31,33) is an adhesive layer in contact with the first holographic layer.

5. Glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that: - n0 is between 1.5 and 1.62 at XI, - n2 is less than or equal to 1.48 at XI or even to 1.45 and preferably is at least 1.3, - nv is between 1.5 and 1.55 at XI.

6. Glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that n2 is less than or equal to 1.45 with nv greater than n2.

7. A glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims, characterized in that ni is greater than or equal to 1.48 and ni is greater than n0, ni is less than or equal to nHi-

8. Glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that the first hologram is a preferably sinusoidal diffraction grating.

9. Glass roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that the first hologram is an array of off-axis Fresnel zones, in particular obtained from a microlens array.

10. Glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of the preceding claims characterized in that it comprises a light source optically coupled to the second sheet, monochromatic light source at said first wavelength XI and a full mid-height bandwidth preferably of at most 30nm, XI is preferably selected from a first range LB1 from 450 nm up to and including 510 nm or from a second range LB2 from 510 nm up to and including 560 nm, or from a third range LB3 from 560 to 650 nm, or better from 620nm to 650nm.

11. Glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to the preceding claim characterized in that an upper intermediate layer (31,33) is an interlayer layer of index n; equal to 1.48 in the visible, and in that XI is equal to in the first range LB2 or LB1, preferably LB2.

12. A glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to any one of claims 1 to 9, characterized in that it comprises a polychromatic light source, optically coupled to the second sheet, the polychromatic light source emitting: - at said first wavelength XI selected from a first range which is in a first range LB1 going from 450 nm up to 510 nm excluded or in a second range LB2 going from 510 nm up to 560 nm excluded, or in a third range LB3 going from 560 to 650 nm, or better from 620nm to 650nm, - to a second main wavelength X2 distinct from XI chosen in a second range distinct from the first range and which is in the first, second or third ranges LB1, LB2, LB3„ , - and preferably at a third main wavelength X3 distinct from XI and X2 and chosen in a third range distinct from the first range and the second range which is in the first, second or third ranges LB1, LB2, LB3 - preferably the first beach is in LB2, the second beach is in LB1, the third beach is in LB3.

13. A glazed roof (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100) according to the preceding claim, characterized in that the first multiband hologram also diffracts at the second wavelength X2, the first functional zone having a refractive index nH2 at X2, or even diffracts also at the third wavelength X3, the first functional zone having a refractive index nH3 at X3, or in that the roof comprises a second hologram diffracting at X2 between the first hologram and face F3, with a second holographic layer having a second functional zone having a refractive index nH2 at X2, and optionally the roof comprises a third hologram diffracting at X3, between the second hologram and face F3, with a third holographic layer having a third functional zone having a refractive index nH3 at X2,n2a being the lowest refractive index at X2 in the visible: a) in the case of a second functional zone, among the refractive indices at X2 of the lower intermediate layer(s) above the second functional zone, the first functional zone, the upper intermediate layer(s) and up to and including the first tinted layer, b) or in the case of a first multiband hologram, among the indices of, refraction of the upper intermediate layer(s) between the first excluded holographic layer and up to the first included tinted layer (c) or in the absence of a tinted upper intermediate layer or upper intermediate layer, n2a being equal to nva with nva the refractive index at / .2 in the visible of the first sheet And (i) ν being the lowest refractive index at / .2 among the refractive indices of the possible lower intermediate layer(s) below the second functional zone, the index nH2 of the second functional zone, and nOa which is the visible refractive index at / .2 of the second sheet j) or in the case of a first bare multiband hologram, where nH2 is the lowest refractive index at / .2 among the refractive indices of the possible lower intermediate layer(s) (below the first functional zone), nOa is the index at / .2 in the visible of the second sheet, the optical function of said second hologram or first multiband hologram being chosen such that a portion of light rays injected at / .2 into the second glass sheet, guided into the roof, reaches the second hologram or first multiband hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of angles of incidence 02 at face F4, and between -arcsin (l / nOa) and arcsin (l / nOa) and possibly, n2b being the lowest refractive index at / .3 in the visible spectrum: a') in the case of a third functional zone, among the refractive indices at / .3 of the lower intermediate layer(s) above the third functional zone, the first functional zone, the upper intermediate layer(s) and up to and including the first tinted layer, b') or, in the case of a first multiband hologram, among the refractive indices of the upper intermediate layer(s) between the first excluded holographic layer and the first included tinted layer (c) or in the absence of a tinted upper intermediate layer or upper intermediate layer, n2b being equal to nvb with nvb the refractive index at / .3 in the visible of the first sheet And nib being the lowest refractive index at X3 among the refractive indices of the possible lower intermediate layer(s) below the third functional zone, the index nH3 of the third functional zone, and nOb which is the refractive index at X3 in the visible of the second sheet the optical function of said third hologram or of the first multiband hologram being chosen such that a portion of light rays injected at X3 into the second sheet of glass, guided in the roof, reaches the third hologram or the first multiband hologram and is diffracted and extracted from the roof on the side of face F4 in all or part of the range of angles of incidence 02 at face F4, and between -arcsin (l / nOb) and arcsin (l / nOb) for a given observation direction in the 02 range: -the first diffracting hologram at XI having a maximum diffraction efficiency in a first sub-range of 01a with a width of at least 1° -the second hologram or the first multiband diffracting hologram at X2 having a maximum diffraction efficiency in a second sub-range of 01b with a width of at least 1° with partial or disjoint overlap of 01a -the possible third hologram or the first multiband hologram, diffracting at X3, having a maximum diffraction efficiency in a third sub-range of 01c with a width of at least 1° with partial or disjoint overlap with first and second sub-ranges 01a and 02a.

14. A glazed roof according to any one of the preceding claims, characterized in that it comprises: - a first upper intermediate layer (31,33), of interlayer, of crosslinked adhesive material, of refractive index equal to n2 preferably of at most 1.45 to XI - a first lower intermediate layer (32), of interlayer, with a refractive index of at least 1.48 to XI, in particular PVB or EVA - a second sheet of mineral glass.

15. Glass roof according to any one of the preceding claims characterized in that the first holographic layer (60) is a photopolymer, the first functional area (60) has an index modulation dn around a refractive index nH0 at an inscription wavelength in the visible X0 which is preferentially in the spectral band of a monochromatic or polychromatic light source optically coupled to the second sheet.

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