FR3038691A3 - LIGHTING DIPOSITIVE WITH LINEAR OPTICAL - Google Patents

Abstract

Light-emitting diode linear illumination device comprising at least: - an elongate body (2) comprising at least one receiving surface (3) of at least one substrate (4) carrying a linear source of light comprising at least one row ( R) of electroluminescent diodes (5) aligned along a longitudinal axis (L) of the body and at least partially delimiting at least one elongate linear illumination chamber (11) in which the diodes (5) are located; elongated linear cover (20) closing the lighting chamber (11), characterized in that the cover (20) forms, in relation to the linear source, a linear lens (21), at least translucent, of parallel longitudinal axis to the longitudinal axis (L) of the body (2) and symmetrical with respect to a sagittal plane (S), with an outer emitting face (23) of the light and an inner receiving face (22) of the light diodes (5), of which - the transmitting face (23), seen in cross-section nsversale, has a convex central portion bordered by two flat lateral parts, and - the receiving face (22), seen in transverse cross section, comprises: - a central region at least partially convex located opposite the central region the emission side to form an optical system ensuring a concentration of a light portion emitted by the diodes in an angular sector symmetrical with respect to the sagittal plane of a value between 20 ° and 120 °, - two flat lateral parts substantially parallel to the flat side portions of the transmitting face to form two lateral light diffusion wings.

Description

[01] The present invention relates to the technical field of lighting using light emitting diode (LED) light-emitting diode (LED) sources. The invention relates more particularly to so-called linear LED lighting devices intended to be a substitute for lighting systems using fluorescent linear tubes with mercury vapor or other.

[02] Lighting with fluorescent tubes such as, for example, used inside industrial buildings, particularly in storage warehouses, implements luminaires fixed in height, and aligned to illuminate spans. Each luminaire then comprises one, two or three parallel linear fluorescent tubes. These inexpensive luminaires actually make it possible to produce light, but they do not make it possible to obtain satisfactory illumination at ground level or in a volume between the ground and a height of two meters, given the height at which they are generally located. , from 4 to 10 meters and how the tubes emit light on their entire periphery. Moreover, these luminaires do not make it possible to obtain an optimized electrical energy consumption and induce disturbances of the power supply networks to which they are connected because of their mode of operation and the systems used when they are switched on.

[03] With the development of light-emitting diodes, linear fluorescent tube luminaires are replaced by linear light-emitting diode luminaires. In order to ensure quality ground lighting, when the luminaire is located at a great height, it is proposed to associate each diode with an individual optical system, said secondary lens which focuses and focuses the light, for example in a cone having an apex angle of about 20 ° to 30 °, so as to obtain the desired floor lighting.

[04] However, the implementation of individual optical systems associated with each diode greatly increased the manufacturing cost of the luminaire which can be prohibitive for lighting in industrial environment in particular. Moreover, in some implementation configuration it is not always necessary to illuminate the ground just below and in the axis of the luminaire but it may be desirable to illuminate an area located on the side, shifted laterally relative to to the area directly above and in line with the luminaire.

[05] It therefore appeared the need for a new type of linear lighting device adapted to ensure satisfactory lighting, in the axis of the luminaire including from a great height, providing a satisfactory aesthetic and limiting the glare of an observer that while having a manufacturing cost significantly lower than that of the luminaires comprising an optical system of light concentration associated with each light emitting diode.

[06] In order to achieve this object, the invention relates to a linear light-emitting diode illumination device comprising at least: an elongated body comprising at least one receiving surface of at least one substrate carrying a linear source of light comprising at least one row of light-emitting diodes aligned along a longitudinal axis of the body and at least partially delimiting at least one elongate linear illumination chamber in which the diodes are located; - an elongate linear cover closing the illumination chamber , characterized in that the cap forms, in relation to the linear source, a linear lens, at least translucent, of longitudinal axis parallel to the longitudinal axis (L) of the body and symmetrical with respect to a sagittal plane, with a external light emitting face and an internal light receiving face of the diodes, whose transmitting face, seen in transverse cross-section, possesses a central portion of convex shape bordered by two flat lateral parts, and - the receiving face, seen in transverse cross section, comprises: - a central region at least partially convex located opposite the central region of the emission face to form an optical system providing a concentration of a light portion emitted by the diodes in an angular sector symmetric with respect to the sagittal plane of a value between 20 ° and 120 °, - two flat lateral portions substantially parallel to the flat lateral portions of the emission face to form two lateral wings of light diffusion.

[07] The central part of the linear lens makes it possible to obtain a concentration of light capable of producing lighting in accordance with the standard in force, particularly for lighting of traffic and office space in commercial buildings. In addition, the presence of the lateral wings substantially attenuates the glare of an observer of the lighting device by increasing the width of the "perceived light source" or seen by the observer. Indeed, the lateral wings form light guides which recover and diffuse the light emitted laterally by the diodes constituting the light source within the meaning of the invention.

According to a characteristic of the invention, the planes of the flat lateral parts form an angle of between 40 ° and 200 ° and, preferably, between 90 ° and 180 °. According to another characteristic of the the wings have a thickness of between 3 mm and 10 mm.

[10] According to a feature of the invention, the wings each comprise at their medial end an entrance face of the light which is flat and borders the central region of the receiving face. Such a configuration of the input face of the light guides formed by the wings makes it possible to recover the light emitted laterally by the diodes.

[11] In the same direction and according to a variant of this characteristic, the input faces are substantially parallel to the sagittal plane.

[12] Still in the same objective of optimizing the recovery of the lateral light, the ends of the input faces located opposite the emission face are located substantially in a plane defined by the support substrate of the diodes or beyond this plane away from the transmitting face.

[13] According to a feature of the invention, the central portion of the emission face has a radius of curvature greater than or equal to 8 mm and preferably between 13 mm and 30 mm. Such dimensions make it possible to obtain a good compromise between the size of the lighting device and its efficiency.

[14] According to another characteristic of the invention, the central region of the receiving face comprises a central convex diopter to form with the corresponding central portion of the emission face a biconvex lens. Such a configuration makes it possible to concentrate well in the area of interest.

[15] According to a variant of this characteristic, the central diopter has a radius of curvature of between 5 mm and 30 mm.

[16] According to another variant of this characteristic, the biconvex lens has a thickness measured, between the vertices of its opposite convex faces, between 5 mm and 20 mm.

[17] According to yet another variant of this feature, the central diopter of the receiving face is bordered by at least two parallel prisms which are located opposite to each other with respect to the central diopter and which have each a medial side and a side at least partially flat side connecting at a vertex of the corresponding prism. The implementation of these lateral parallel prisms allows better recovery of the light from the diodes. It should be noted that more than one prism can be used on each side of the central diopter.

[18] In the context of this variant, the prisms may each have a height, measured between the apex of the corresponding prism and the emission face, in a direction normal to the emission face, between 5 mm and 20 mm .

[19] According to one characteristic of the invention, the apex of the primary lens of each diode is located between a plane tangent to the apex of the central part of the emission face and a parallel plane passing through the point or points of the receiving face furthest from the top of the central part of the transmitting face.

[20] According to a feature of the invention, the central portion of the receiving face defines a cavity for receiving the diodes and / or primary optics of the diodes. It should be noted that the receiving cavity may in particular but not necessarily be arranged in part at least inside the central convex diopter of the receiving face in the case where the latter comprises such a central convex diopter.

[21] According to another characteristic of the invention, the linear light source comprises several longitudinal rows of parallel light emitting diodes.

[22] Of course, the various features, variants and embodiments of the lighting device according to the invention can be associated with each other in various combinations to the extent that they are not incompatible or exclusive of each other .

[23] Furthermore, various other features of the invention appear from the attached description made with reference to the drawings which illustrate non-limiting embodiments of a lighting device according to the invention.

[24] Of course, the different features, variants and embodiments of the lighting device according to the invention can be associated with each other in various combinations to the extent that they are not incompatible or exclusive of each other .

[25] Furthermore, various other features of the invention emerge from the attached description made with reference to the drawings which illustrate non-limiting embodiments of a lighting device according to the invention. - Figure 1 is a schematic perspective view partially exploded of a lighting device according to the invention. FIG. 2 is a cross section of the assembled lighting device illustrated in FIG. 1. FIG. 3 is a cross section of the cover forming at least the linear lens of the lighting device illustrated in FIGS. 1 and 2.

[26] A lighting device according to the invention, designated as a whole by the reference numeral 1 in FIGS. 1 and 2, may be qualified as a linear lighting device insofar as it has a linear illumination source E comprising one or more rows R of light-emitting diodes. A linear lighting device according to the invention generally has a length very much greater than the width of the lighting device without the invention excluding an embodiment of the lighting device in which it has a width very close to its width. length by the implementation of a sufficient amount of row of light emitting diodes. The linear qualifier is nonetheless relevant insofar as it relates to the alignment direction of the rows of light-emitting diodes.

[27] The linear lighting device 1 comprises an elongated body 2 which extends along a longitudinal axis L. The elongated body 2 defines at least one receiving surface 3 of at least one substrate 4 carrying at least one row R light emitting diodes 5 aligned along the longitudinal axis L. According to the illustrated example, the elongate body 2 comprises a single receiving surface 3 which is substantially centered with respect to the elongate body 2 and on which is fitted a single substrate 4 carrying a The substrate 4 may, for example, comprise a printed circuit board, on which the light-emitting diodes 5 are soldered. can be made in any other appropriate manner to ensure the mechanical strength of the light emitting diodes 5 and their power supply.

According to the illustrated example, each light-emitting diode 5 is associated, as is more particularly apparent from FIG. 2, with a primary lens 6 which has a convex transmission face 7, it being understood that the transmission face 7 could also be flat. In addition, in this case each light emitting diode 5 is devoid of individual secondary lens. It should be noted that according to the invention the diodes 5 do not necessarily include a primary lens.

[29] According to the illustrated example, the elongate body 2 comprises two planar reflectors 10 located on either side of the receiving face 4. The two planar reflectors 10 extend parallel to the longitudinal axis L and form, with each other and according to the illustrated example, a flat angle.

[30] The elongate body 2 defines with the receiving surface 3 and the planar reflectors 10 a lighting chamber 11 in which the row of light-emitting diodes R, constituting the linear source E, is intended to be partly at least locked.

[31] The lighting device according to the invention also comprises an elongate linear hood 20 which partially closes at least the lighting chamber 11. According to the invention, the hood 20 is also intended to let in or spread the light emitted by each linear source E. For this purpose, the cover 20 is made of an at least translucent and preferably transparent material such as for example a plastic material such as polymethyl methacrylate (PMMA), polyethylene terephthalate (PET) or polypropylene (PP) without this list being neither exhaustive nor exhaustive.

[32] The cover 20 is also adapted to provide a conditioning of the light emitted by the linear source E so as to direct and focus it according to a lighting lobe symmetrical with respect to the sagittal plane. For this purpose, the cover 20 forms, in relation to each linear light source E, a linear lens 21 parallel to the longitudinal axis L of the body 2. According to the example illustrated in FIGS. 1 and 2, the cover 2 comprises a single linear lens 21.

[33] According to the invention, each linear lens 21 comprises an outer emitting face 22 of the light which is symmetrical with respect to a sagittal plane S substantially parallel to the longitudinal axis L. When the cover 20 is fitted on the body 2, the sagittal plane S forms a plane of symmetry of the illumination chamber 11, the reflectors 10 then being the image of one another with respect to the sagittal plane S.

[34] The linear lens 21 also has an inner face 22 for receiving the light of the light-emitting diodes 5 located opposite the outer face 23 of light emission of the light-emitting diodes 5. The linear lens 21 ensures in its together a transmission of the light emitted by said light emitting diodes 5.

[35] As is apparent from Figure 3, the outer face 23 has, in cross section, has a central portion of convex shape, preferably smooth, bordered by two flat lateral parts also preferably smooth. The convex central portion has a radius of curvature R greater than or equal to 8 mm and preferably between 13 mm and 30 mm. Preferably, the outer face 22 has the shape of a circular arc. According to the illustrated example, the planes of the flat lateral parts form an angle α of between 40 ° and 200 ° and preferably between 90 ° and 180 °.

[36] The receiving face 22 is shaped so as to include a central region 30 at least partially convex located opposite the central region of the emission face 23 to form an optical system ensuring a concentration of a light portion emitted by the diodes in an angular sector symmetrical with respect to the sagittal plane S of a value between 20 ° and 120 °. The receiving face also comprises two flat lateral portions 31 substantially parallel to the flat lateral parts 25 of the emission face 23 to form two lateral wings 32 of light scattering. The lateral wings 32 form two light guides which has a thickness e of between 3 mm and 10 mm.

[37] In order to reflect the light in the direction of the faces 25, the plane lateral faces 31 of the reception face 22 may be associated with reflectors, receive a reflective coating, or may comprise texturing or micro-primes or micro-conformations. inducing a reflection of light.

[38] According to the example, illustrated wings 32 each comprise at their medial end a light-input face 35 which is flat and borders the central region 30 of the receiving face. According to the illustrated example, the input faces 35 are substantially parallel to the sagittal plane S.

[39] In this case, the central region 30 of the receiving face comprises a central diopter 36 convex to form with the corresponding central part of the emission face a biconvex lens 37. The central diopter 36 then preferably has a radius of curvature between 5 mm and 30 mm. In addition, the biconvex lens preferably has a thickness E, measured between the vertices of its opposite convex faces 24, 36, between 5 mm and 20 mm.

[40] Still, according to the illustrated example, the central diopter 36 of the receiving face 22 is bordered by at least two parallel prisms 38 which are located opposite one another with respect to the central diopter [ 41] Each prism 38 comprises a medial face 40, in part at least flat, situated on the side of the sagittal plane S and a lateral face 41, in part at least flat, located opposite the sagittal plane with respect to the medial face 40. The medial and lateral faces of each prism are substantially parallel to the longitudinal axis L. The medial 40 and lateral 41 faces of the same prism join to form the apex 42 of the corresponding prism.

[42] Preferably, but not strictly necessary, the plane portions of the lateral 41 and medial faces 40 of the same lateral prism form an angle of between 15 ° and 60 °. In addition, the flat portion of the medial face 40 of each prism forms with the sagittal plane S an angle of between 0 ° and 45 ° in absolute value. Similarly, the flat portion of the lateral face of each prism forms with the sagittal plane S an angle of between 5 ° and 80 ° in absolute value [43] Moreover, according to the illustrated example and so that the linear lens 21 collecting a maximum of the light emitted by the linear source E to concentrate it in the preferred direction D, the prisms each have a height (h), measured between the apex of the corresponding prism and the emission face, in a direction normal to the emission side, between 5 mm and 20 mm.

[44] In the present case, the top of the emission face 7 of the primary lens of each light-emitting diode 5 is also located between a plane P20 tangential to the vertex the central part of the emission face and a parallel plane P35 passing through the point or points of the receiving face furthest from the top of the central part of the transmitting face.

[45] It may be noted that in the configuration shown, the central part of the reception face defines a cavity for receiving the diodes forming the light source.

[46] A linear lighting device, according to the invention and as thus achieved, allows to redirect a large part of the light emitted by the diodes in the preferred direction S. Indeed, the linear biconvex medial lens 37 collimate the light from the diodes 5 in the preferred direction S in a narrow cone centered on its optical axis O while the linear prisms allow, after total internal reflection to the linear lens 21, to redirect the light in the preferred direction. In addition, the lateral flanges 32 ensure a recycling of the light possibly reflected by the reception face 22 and the light from the light-emitting diodes 5 which would not have reached the reception face 22 directly.

[47] The lighting device described above in connection with FIGS. 1 to 3 comprises a linear light source E formed of a single row R of light-emitting diodes. However, according to the invention, the linear source of light E could comprise several rows of LEDs R juxtaposed.

[48] Of course, various other variants of the lighting device according to the invention can be envisaged within the scope of the appended claims.

[49] Furthermore, it should be understood that several linear lighting devices according to the invention can be associated in various combinations to form a luminaire.

Claims (15)

A linear light-emitting diode illumination device comprising at least: an elongated body (2) comprising at least one receiving surface (3) of at least one substrate (4) carrying a linear source of light comprising at least one row (R) of light-emitting diodes (5) aligned along a longitudinal axis (L) of the body and at least partially delimiting at least one elongate linear illumination chamber (11) in which the diodes (5) are located, an elongate linear hood (20) closing the lighting chamber (11), characterized in that the cover (20) forms, in relation to the linear source, a linear lens (21), at least translucent, of axis longitudinal parallel to the longitudinal axis (L) of the body (2) and symmetrical with respect to a sagittal plane (S), with an outer emitting face (23) of the light and an inner receiving face (22) of the light of the diodes (5), of which - the transmitting face (23), seen in cross section transverse, has a convex central portion bordered by two flat lateral parts, and - the receiving face (22), seen in transverse cross section, comprises: - a central region at least partially convex located opposite the central region the emission side to form an optical system ensuring a concentration of a light portion emitted by the diodes in an angular sector symmetrical with respect to the sagittal plane of a value between 20 ° and 120 °, - two flat lateral parts substantially parallel to the flat side portions of the transmitting face to form two lateral light diffusion wings. 2. Linear lighting device according to the preceding claim, characterized in that the planes of the flat side portions form an angle of between 40 ° and 200 ° and preferably between 90 ° and 180 °. 3. Linear lighting device according to one of the preceding claims, characterized in that the wings have a thickness of between 3 mm and 10 mm. 4. Linear lighting device according to one of the preceding claims, characterized in that the wings each comprise at their medial end an entrance face of the light which is flat and borders the central region of the receiving face. . 5. Lighting device according to the preceding claim characterized in that the input faces are substantially parallel to the sagittal plane. 6. Lighting device according to claim 4 or 5, characterized in that the ends of the input faces located opposite the emission face are located substantially in a plane defined by the support substrate of the diodes or beyond this plane by moving away from the transmitting face. 7. Lighting device according to one of the preceding claims, characterized in that the central portion of the emission face has a radius of curvature greater than or equal to 8 mm and preferably between 13 mm and 30 mm. 8. Lighting device according to one of the preceding claims, characterized in that the central region of the receiving face comprises a central convex diopter to form with the corresponding central portion of the emission face a biconvex lens. 9. Lighting device according to the preceding claim characterized in that the central diopter has a radius of curvature of between 5 mm and 30 mm. 10. Lighting device according to claim 8 or 9, characterized in that the biconvex lens has a thickness, measured between the vertices of its opposite convex faces, between 5 mm and 20 mm. 11. Illumination device according to one of claims 8 to 10, characterized in that in that the central diopter of the receiving face is bordered by at least two parallel prisms which are located opposite one of the other relative to the central diopter and which each have a medial side and a partially flat at least lateral face connecting at a vertex of the corresponding prism. 12. Lighting device according to the preceding claim characterized in that the prisms each have a height (H), measured between the apex of the corresponding prism and the emission face, in a direction normal to the emission face, included between 5 mm and 20 mm. 13. Linear lighting device according to one of the preceding claims, characterized in that the apex of the primary lens (6) of each diode (5) is located between a plane tangent to the vertex da the central portion of the face d emission and a parallel plane passing through the point or points of the receiving face farthest from the top of the central part of the emission face. 14. Linear lighting device according to one of the preceding claims, characterized in that the central portion of the receiving face defines a cavity for receiving the diodes and / or primary optics of the diodes. 15. Linear lighting device according to one of the preceding claims, characterized in that the linear light source comprises several rows (R) longitudinal parallel light emitting diodes.