Luminous glazing unit for architectural use or use in furnishings or a means of public transport

Abstract

A luminous glazing unit for architectural use or use in furnishings or a system of public transport, includes a first glazing pane, made of organic or mineral glass, of refractive index n1 of at least 1.4 with first and second main faces; a light source, coupled to the first glazing pane; and a light-extracting system including a scattering layer of width of at least 1 cm including scattering dielectric particles bound by a transparent matrix of refractive index n2. The scattering particles are mainly microparticles that are spaced apart from one another and that include a shell made of a transparent dielectric material and making contact with the transparent matrix, the shell surrounding a core of refractive index n3 of at most 1.15 and of largest dimension called D3 in a range extending from 5 m to 200 m, the microparticles having a largest dimension called D smaller than 2D3.

Claims

1. A luminous glazing unit comprising: a glazing module with an edge face and two main faces, said glazing module including at least one first glazing pane, made of organic or mineral glass, of refractive index n1 of at least 1.4 with first and second main faces; a light source optically coupled to the glazing module, the glazing module forming a guide of light emitted by the light source; and a light-extracting system configured to extract the guided light in order to form a scattering zone of width of at least 1 cm, said light-extracting system including a scattering layer comprising scattering dielectric particles bound by a matrix, said scattering layer being associated with one of the first or second main faces; wherein the matrix is transparent and of refractive index n2 at least equal to n1 or such that n1-n2 is at most 0.15 and wherein the scattering particles are mainly microparticles that are spaced apart from one another and that comprise a shell made of a transparent dielectric material and making contact with the transparent matrix, said shell surrounding a core of refractive index n3 of at most 1.15, said core having a largest dimension D.sub.3 in a range extending from 5 m to 200 m, the microparticles having a largest dimension called D smaller than 2D.sub.3.

2. The luminous glazing unit as claimed in claim 1, wherein a degree of coverage of the microparticles is at most 20%.

3. The luminous glazing unit as claimed in claim 1, wherein the microparticles are hollow.

4. The luminous glazing unit as claimed in claim 1, wherein the dielectric material of the shell is mineral glass, silica or a metal oxide.

5. The luminous glazing unit as claimed in claim 1, wherein said largest dimension D.sub.3 is in the range extending from 20 m to 100 m.

6. The luminous glazing unit as claimed in claim 1, wherein the scattering layer includes a layer binding the microparticles made of a material chosen from an organic binder or a mineral binder and/or the scattering layer includes a PVB or EVA layer binding the microparticles.

7. The luminous glazing unit as claimed in claim 1, wherein the scattering layer is directly on the first main face or the second main face of the first glazing pane, and, defining the haze H1, in the off state, of the first glazing pane and scattering layer together, H1 is at most 10%.

8. The luminous glazing unit as claimed in claim 1, wherein the scattering layer is directly on the first main face or the second main face of the first glazing pane, and, the image clarity, in the off state, of the first glazing pane and scattering layer together, is at least 90%.

9. The luminous glazing unit as claimed in claim 1, wherein the light source includes a set of light-emitting diodes on a PCB carrier.

10. The luminous glazing unit as claimed in claim 1, wherein the light source is optically coupled to the first glazing pane, wherein a layer of porous sol-gel silica of refractive index of at most 1.3 is on the second main face of the first glazing pane, wherein the scattering layer is on the first main face or a side of the second main face of the first glazing pane and, when the scattering layer is on a side of the second main face, the porous silica layer has one or more discontinuities and the scattering layer faces the one or more discontinuities, and wherein optionally the glazing module is a laminated glazing unit including said first glazing pane made of mineral glass, and, on the side of the second main face, a lamination interlayer made of an optionally tinted thermoplastic polymeric material, and a second glazing pane made of mineral glass optionally including an absorbing and/or scattering layer.

11. The glazing unit as claimed in claim 1, wherein the glazing module is a laminated glazing unit including said first glazing pane made of mineral glass, and including on the second main face side a lamination interlayer made of a thermoplastic polymeric material, and a second glazing pane made of mineral glass.

12. The luminous glazing unit as claimed in claim 1, wherein the glazing module is a laminated glazing unit including said first glazing pane made of mineral glass, a lamination interlayer made of a thermoplastic polymeric material and a second glazing pane made of mineral glass, and wherein the microparticles are bound by the polymeric material forming the transparent matrix.

13. The luminous glazing unit as claimed in claim 10, wherein the lamination interlayer is a PVB or an EVA.

14. The luminous glazing unit as claimed in claim 1, wherein the luminous glazing unit forms an architectural glazing unit or a glazing unit used in furnishings or a means of public transport.

15. The luminous glazing unit as claimed in claim 1, wherein the luminous glazing unit forms an insulating glazing unit that includes an additional glazing pane with third and fourth main faces, the third main face, the innermost, being spaced apart from the glazing module, by a gas-filled cavity, a framing first polymeric seal being arranged on the a periphery of the third main face and making contact with the glazing module.

16. The luminous glazing unit as claimed in claim 15, wherein the luminous glazing unit forms a side window of a train, tram or a subway train, a door of a refrigerated appliance, a window, a skylight, or a glazed door.

17. The luminous glazing unit as claimed in claim 1, wherein the luminous glazing unit forms a planar and tempered, clear or extra-clear single glazing unit, the first glazing pane thus being planar and tempered and clear or extra-clear.

18. The luminous glazing unit as claimed in claim 1, further comprising a profile for mounting the glazing unit, the light source being in a volume between the mounting profile and the edge face of the glazing module, the profile including a web facing the edge face of the glazing module.

19. The luminous glazing unit as claimed in claim 18, wherein the light source includes a set of light-emitting diodes on a PCB carrier and wherein the luminous glazing unit includes a profile bearing the PCB carrier in the volume between the mounting profile and the edge face of the glazing module.

20. The luminous glazing unit as claimed in claim 2, wherein the degree of coverage of the microparticles is at most 1%.

21. The luminous glazing unit as claimed in claim 3, wherein the dielectric material of the shell is mineral glass, silica or a metal oxide.

22. The luminous glazing unit as claimed in claim 7, wherein H1 is at most 2%.

Description

(1) The present invention will be better understood and other details and advantageous features of the invention will become apparent on reading about examples of luminous glazing units according to the invention, which are illustrated by the following figures:

(2) FIG. 1 shows a schematic cross-sectional view of a monolithic luminous glazing unit in a first embodiment of the invention;

(3) FIG. 1 a is a view of a hollow microparticle used for light extraction;

(4) FIG. 2 shows a schematic cross-sectional view of a laminated luminous glazing unit in a second embodiment of the invention;

(5) FIG. 3 shows a schematic cross-sectional view of a laminated luminous glazing unit forming a luminous mirror in a third embodiment of the invention;

(6) FIG. 4 shows a schematic cross-sectional view of a decorative laminated luminous glazing unit in a fourth embodiment of the invention; and

(7) FIG. 5 shows a schematic cross-sectional view of a luminous glazing unit that is an insulating glazing unit in a fifth embodiment of the invention.

(8) It will be noted that for the sake of clarity the various elements of the objects shown are not necessarily reproduced to scale.

(9) FIG. 1 shows a schematic cross-sectional and partial view of a monolithic luminous glazing unit 100 in a first embodiment of the invention.

(10) In FIG. 1, the glazing unit according to the invention includes a glazing module taking the form of a single glazing unit with an edge face and main faces denoted face A and face B. It therefore includes a for example rectangular first glazing pane 1 (dimensions of 300300 mm for example) made of planar and tempered mineral glass having a first main face 11 corresponding to the face A and a second main face 12 corresponding to face B, and a for example rounded or flat (to prevent flakes) here longitudinal (or as a variant lateral) edge face 10, for example a sheet of extra-clear, soda-lime-silica glass such as Diamant glass sold by Saint-Gobain Glass, of thickness equal for example to 3 mm, said glazing pane having a refractive index n1 of about 1.51 at 550 nm.

(11) The first glazing pane is alternatively made of polycarbonate or even of PMMA.

(12) Light-emitting diodes 4 border the first glazing pane 1. It is here a question of top-emitting diodes. Thus, these diodes 4 are aligned on a PCB carrier 41 facing the first edge face 10, for example a parallelepipedal strip, and their emitting faces are perpendicular to the PCB carrier and to the edge face 10. The PCB carrier is for example fastened by optical (or a transparent double-sided) adhesive 6 to the edge face.

(13) The PCB carrier with the diodes is between the first edge face and a metal (aluminum or stainless steel, to dissipate heat) or even (stiff) plastic profile 7 of U-shaped cross section, including a web 70 facing the first edge face, a first (optional but preferred) flange 71 extending as far as to be facing the peripheral edge of the first face 11 and a second (optional but preferred) flange 72 extending as far as to be facing the peripheral edge of the second face 12. The PCB carrier may be against or fastened to the web 70 (the adhesive 6 optionally being omitted). In the case of side-emitting diodes, the PCB carrier may be against or fastened to the first or second flange.

(14) The light-emitting diodes each include an emitting chip able to emit one or more rays in the visible, which one or more rays are guided in the first glazing pane 1. The diodes are small in size, typically a few millimeters or less and in particular about 221 mm in size, without optics (lens) and preferably not pre-encapsulated in order to decrease bulk as much as possible.

(15) The distance between the diodes and the edge face 10 is as small as possible, for example from 1 to 2 mm.

(16) The main emission direction is perpendicular to the face of the semiconductor chip that for example has a multi-quantum well active layer in an AlInGaP or other semiconductor technology.

(17) The light cone is a Lambertian cone of +/60.

(18) The glazing unit 100 may have a plurality of luminous zones, the one or more luminous zones preferably occupying less than 50% of the area of at least one face, in particular of given geometry (rectangular, square, round, etc.).

(19) The light ray A (after refraction at the edge face 10) propagates by total internal reflection (at the second face 12 and from the face 11 called face A) in the first glazing pane 1 forming a light guide. For the light extraction, a scattering layer 5 is deposited on the second face 12 of the first glazing pane. It includes a preferably colorless transparent matrix 50 of refractive index n2 at least equal to n1 or such that n1n2 is at most 0.15, incorporating scattering particles 51.

(20) Microparticles that are preferably hollow, formed from a dielectric shell 52 surrounding a gaseous core 53 of refractive index n3 of at most 1.15, preferably air, are chosen, as shown in FIG. 1a.

(21) The diameter D.sub.3 (diameter of the core) is in a range extending from 5 m to 200 m and better still ranging from 20 m to 100 m. The diameter D of the microparticles (outside diameter of the shell) is smaller than 2 D.sub.3. The thickness of the shell is more than 500 nm.

(22) The degree of coverage of the microparticles is preferably 1% to 10%. It is determined by observation by optical microscope.

(23) The scattering zone is rectangular and 10 cm by 10 cm in size. The scattering zone is a continuous, unapertured layer.

(24) By way of illustration, the microparticles are hollow glass microbeads of average diameter D of 65 m (product denoted Glass Bubbles K1 sold by 3M) and the shell of which is of submicron-sized thickness E4 of a few hundred nm, and are placed in a colorless resin based on silicone-epoxy denoted SILIKOPON sold by TEGO EVONIK. The resin filled with hollow microbeads is spread over the second face 12 using a motorized bar coater in order to obtain a thickness of 120 m on the second face 12.

(25) For example, the illuminant is placed on the side opposite to the scattering layer in order to take measurements of haze and image clarity.

(26) In a first example, the concentration of the microspheres is chosen in order to achieve a degree of coverage of 1%. The haze H.sub.1 of the first glazing pane with the scattering layer is 1.5% and, in a zone without the scattering layer, the haze is lower than 1%. The image clarity of the first glazing pane with the scattering layer is 99% and, in a zone without the scattering layer, the image clarity is almost 100%. The luminance is higher than 1 cd/m.sup.2.

(27) In a second example, the concentration of the microspheres is chosen in order to achieve a degree of coverage of 5%. The haze H.sub.1 of the first glazing pane with the scattering layer is 5% and, in a zone without the scattering layer, the haze is again lower than 1%. The image clarity of the first glazing pane with the scattering layer is 97% and, in a zone without the scattering layer, the image clarity is again almost 100%. The luminance is about 10 cd/m.sup.2.

(28) When the diodes are turned off, the first glazing pane coated with the scattering layer is of light transmission T.sub.L of about 88%.

(29) The scattering layer may be deposited before or after tempering, preferably after if it is a question of a resin transparent matrix.

(30) Alternatively, the scattering layer 5 is on face A.

(31) The ray A refracted in the scattering layer 5 encounters a scattering hollow microsphere allowing light to be extracted in particular toward face A.

(32) The small number of hollow microspheres combined with the choice of a transparent matrix allows the haze H1 of the first glazing pane coated with the scattering layer to be limited.

(33) It is possible to choose diodes emitting colored and/or white light in order to provide ambient lighting, light for reading, etc. Red light may be chosen, optionally in alternation with green light, for signaling purposes in a train.

(34) When the diodes are turned on, the extraction may form a luminous drawing, for example a logo or a trademark.

(35) Alternatively, it is possible to add a discontinuous optical isolator on either side of the scattering layer and a decorative layer, for example a continuous colored background. This decorative layer is not necessarily on the scattering layer.

(36) Alternatively, it is possible to add an optical isolator on the second face and a decorative layer, for example a continuous colored background. The scattering layer is then on the first face.

(37) Alternatively, it is possible to add a mirror layer (protected silver-containing layer) on the second face, to form a covering mirror or a partial mirror. The scattering layer is then on the first face.

(38) In FIG. 2, the luminous glazing unit 200 differs from that described in FIG. 1 in that it is a question of a laminated glazing unit which in addition includes: a lamination interlayer 2, for example a clear PVB of 0.76 mm thickness, preferably of haze of at most 1.5%, with a here longitudinal edge face 20 substantially aligned with the longitudinal edge face 10, said lamination interlayer having a refractive index n.sub.f, lower than n1, equal to 1.48 at 550 nm; and a second glazing pane 5 of the same size and same glass composition with a main face called the internal or lamination face 12 facing the second face 12, and another main face 11 corresponding to face B, and an edge face 10 that here is longitudinal.

(39) Guiding occurs in the first glazing pane and for other rays between face A and face B.

(40) In fact, the diodes may be placed anywhere on the edge face of the laminated glazing unit and likewise the scattering layer without excessively penalizing luminance

(41) Luminance is increased a little if an optical isolator is added to face 12 on either side of the scattering layer (on either side of the scattering layer if on face 12) or even on the scattering layer.

(42) Alternatively, in particular for architectural applications or for furnishing applications, the lamination interlayer 2 is a clear EVA of 0.76 mm thickness, preferably of haze of at most 1.5% and of refractive index n.sub.f substantially equal to n1. In this case, light is above all guided between face A and face B. Here again, the diodes may be placed anywhere on the edge face of the laminated glazing unit and likewise the scattering layer without excessively penalizing the luminance

(43) Alternatively, the second glazing pane 5, of same size, is: made of tinted mineral glass for example the glass VENUS VG10 or TSA 4+ sold by Saint-Gobain Glass; and/or textured or with a (tinted or scattering) decorative layer on face 11 or on face 12.

(44) Alternatively or cumulatively, the lamination interlayer is tinted.

(45) In the latter two configurations, the diodes are very preferably placed facing the first glazing pane and the scattering layer is placed on the first glazing pane and PVB is preferred to EVA or any other material of lower index than the glass 1. Luminance is greatly increased if an optical isolator is added to face 12 (on either side of the scattering layer if on face 12).

(46) In one alternative embodiment (not illustrated) of a laminated glazing unit, differing in the absence of the resin from that described in FIG. 1, the microparticles (hollow glass microbeads) are bound by the clear lamination interlayer made of PVB or EVA. For example, the microparticles are spread over the second face (lamination face) of the first glazing pane then the lamination interlayer is affixed before the lamination cycle is carried out. As a precautionary measure, the beads may even be pre-fastened via spots of optical adhesive on the second face, before the lamination. Alternatively, the microparticles are spread over the main face of the lamination interlayer intended to make contact with the first glazing pane then the first glazing pane is affixed before the lamination cycle is carried out. As a precautionary measure, the beads may even be pre-fastened via spots of optical adhesive to this face of the interlayer, before the lamination.

(47) In FIG. 3, the luminous glazing unit 300 differs from the luminous glazing unit 200 described in FIG. 2 in that the face B is covered with a mirror layer 80, for example a silver-plated layer protected by an overlayer. The mirror function is preserved in the off state in the scattering zone.

(48) It may rather be preferable to place the scattering layer closer to the edge face 10 in order to leave a large central mirror zone (and the scattering layer is then shifted from the mirror layer). It is possible to double the means in order to have two peripheral luminous zones (two vertical or horizontal bands that are unapertured or that take the form of a network of features, and two sets of diodes on opposite edge faces)

(49) Guiding occurs in the first glazing pane and for other rays between face A and face B.

(50) The diodes may be placed anywhere on the edge face of the laminated glazing unit and likewise the scattering layer (excluding face B in any case) without excessively penalizing the luminance.

(51) Luminance is increased a little if an optical isolator is added to face 12 on either side of the scattering layer (on either side of the scattering layer if on face 12) or even on face 12.

(52) In FIG. 4, the luminous glazing unit 400 differs from the luminous glazing unit 200 described in FIG. 2 firstly in that the face 11 or B is covered with a decorative layer 81, for example an unapertured or patterned colored enamel layer. The luminous glazing unit 400 also differs by the porous sol-gel silica layer of 400 nm thickness deposited on the second face 12 before lamination, said layer being discontinuous in order to leave the adjacent (beside and making contact) scattering layer on the second face 12. Alternatively, the scattering layer 5 is on face 11 or even under the optical isolator.

(53) The decoration remains visible in the off state in the scattering zone.

(54) As a variant, it is possible to print a photo on the face 12 with one or more free zones intended to face one or more scattering zones (design with lamp, luminary, streetlight in a town, etc.).

(55) As a variant, a black or dark (masking) enamel limited to a peripheral zone on face 11 or 12 on the optical-coupling side is thus isolated by the optical isolator 5.

(56) As a variant, the layer 8 is removed, another scattering layer or the same scattering layer as that on the first glazing pane is used and a second light source is added facing the edge face 10 of the second glazing pane. It is possible to have luminous zone that are turned on independently and of distinct colors.

(57) In FIG. 5, the luminous glazing unit 500 differs from the luminous glazing unit 100 described in FIG. 1 above all in that it is a question of a double-glazed insulating glazing unit, here for a refrigerated-appliance door.

(58) This luminous glazed door 400 comprises a glazing module forming an insulating glazing unit with an external main face A or 11 user-side and an internal main face 11 (shelves-side) including: a first glazing pane including the external face A and a first edge face formed from four edges including a first longitudinal edge, said first glazing pane here being a single pane including a first sheet 1 made of glass having a first main face 11 and a second main face 12, the first face therefore being the external face, for example a sheet of extra-clear, soda-lime-silica glass of thickness equal to at least 3.8 mm (4 mm or 6 mm as standard); a second glazing pane including the internal face 12 and a second edge face formed from four edges including a second longitudinal edge, said second glazing pane here being a single pane including a second sheet 1 made of glass, with a third face 12 here being the internal face and a fourth main face 11, the faces 12 and 12 being spaced apart by a first gas-filled cavity (filled with air or argon); and on the periphery of the faces 12 and 12, a first framing polymeric seal 9 and an insert 9 forming a spacer.

(59) Usually, the insert 9 is fastened to the interior of the glazing unit 500 via its lateral faces to the faces 12, 12 by butyl rubber 91 which also has the role of making the interior of the insulating glazing unit sealtight to water vapor. The insert 9 is positioned recessed into the interior of the glazing unit and close to the longitudinal edges of the edge faces of said glass sheets, so as to form a peripheral groove into which a first polymer seal 9 is injected, this seal being a mastic, for instance a polysulfide or polyurethane mastic. The mastic strengthens the mechanical assembly of the two glass sheets 1, 1 and ensures sealtightness to liquid water or to solvents.

(60) The light source 4 (diodes) is external to the insulating glazing unit. The diodes are optically coupled to the first longitudinal edge. The diodes are again on a PCB carrier 41 and extend facing the first edge. The PCB carrier 41 does not protrude beyond the first edge face in the direction of the external face 11 and here is adhesively bonded by a conductive adhesive 6a to a metal 8b to dissipate heat. The scattering layer 5 with the microparticles 5 is on the second face 12.

(61) The second glazing pane 1 includes a first layer 15 having a thermal function, on the third face 12.

(62) The PCB carrier 41 and the source 4 are in a cavity bounded by the injection edge and a part referred to as the bearing part 8. The bearing part 8 is a metal profile, here anextruded or foldedsheet made of aluminum of thickness of 1.5 mm. This profile 8 has a portion 8c adhesively bonded by a double-sided adhesive tape 6c to the mastic 9. The bearing part 8 does not touch both the first and second glazing panes 1 in order not to form a thermal bridge. It may in particular be spaced apart by 2 mm from the first face 11 so that the source carrier does not protrude toward the external face 11. The bearing part 8 includes a flange 8a fastened to the face 11 by adhesive 6b.

(63) The glazed door 500 furthermore comprises a framing profile 7 fastened to the insulating glazing unit preferably by an adhesive 6 called a mounting adhesive, and masking the first seal 9 and the insert 9. It forms a longitudinal (vertical in the mounted door) framing jamb 7 fastened to the insulating glazing unit by the mounting adhesive 6.

(64) The framing jamb 7 is made up of two portions in order to prevent any thermal bridging (case if all metal). A first metal portion 7a, for example a profile of L-shaped cross section, contains a dogleg in order to face the optical-coupling edge and to extend over the external face 11: with a portion adhesively bonded to the external face; with a portion facing the edge face of the insulating glazing unit (and shifted from the edge face of the second glazing pane).

(65) The second portion 7b is thermally insulating and preferably polymeric and securely fastened via an adhesive 61 to the doglegged first portion 7a, in order to face the edge face of the second glazing pane and to extend over the internal face 11.

(66) As a variant it may be a question of a window with a suitable framing jamb or even a train side window. The first glazing pane is on the side of the interior of the room or car.