Abstract
A method for assembling optical modules comprising the steps of: providing a frame with at least one opening; providing optical modules to the frame, each of the optical modules being provided to one opening; welding optical modules to the frame; providing a support means to each optical module and/or to each opening, said support means for supporting the optical module at least partially within the opening; assembling the optical modules to the frame by plastically reshaping a material portion in contact with the frame and the optical module, the plastic reshaping occurring under an application of heat and/or pressure; wherein, when the optical module is assembled to the frame, a first bottom surface of the optical module is substantially at same level as second bottom surface of the frame, said first bottom surfaces and second bottom surface adapted for being arranged on a support carrying light sources.
Claims
1. A method for assembling optical modules, said method comprising the steps of: providing a frame with at least one opening, preferably a plurality of openings; providing a plurality of optical modules to the frame, each optical module of the plurality of optical modules being provided to an opening of the at least one opening; providing a support means to each of the plurality of optical modules and/or to each of the at least one opening, said support means being configured for supporting the optical module at least partially within the opening of the frame; assembling the plurality of optical modules to the frame by plastically reshaping a material portion in contact with the frame and the optical module, the plastic reshaping occurring under an application of heat and/or pressure; wherein, when the optical module is assembled to the frame, a first bottom surface of the optical module is substantially at a same level as a second bottom surface of the frame, said first bottom surfaces and second bottom surface being adapted for being arranged on a support such as a PCB, said support carrying a plurality of light sources.
2. The method according to claim 1, wherein the assembling comprises any one of: ultrasonic welding the plurality of optical modules to the frame; laser beam welding the plurality of optical modules to the frame.
3. The method according to claim 1, wherein the assembling comprises plastically reshaping a plurality of pins, each pin of the plurality of pins comprising a portion configured for being plastically reshaped under an application of heat and/or pressure such that the plurality of optical modules are locked between the support means and the reshaped portions of the plurality of pins.
4. The method according to claim 1, wherein the providing of the plurality of optical modules to the frame comprises the step of receiving digital data representative for the optical modules to be included in the frame, and the step of, based on the received digital data, selecting the plurality of optical modules from a storage multiple different optical modules.
5. (canceled)
6. The method according to claim 2, wherein each optical module of the plurality of optical modules has a flat bottom surface, and wherein the welding comprises welding a contact surface of a peripheral edge portion of the optical module to a contact surface of the frame, wherein preferably said contact surfaces are provided substantially parallel to the flat bottom surface .
7. (canceled)
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. The method according to claim 2, wherein the welding is ultrasonic welding, and wherein the optical module and the frame are welded along joining surfaces, and wherein at least one surface of the joining surfaces is provided with an energy director configured to concentrate ultrasonic energy and to initiate melting during the welding; and wherein preferably the joining surfaces form any one of the following joints: butt joints, step joints, tongue and groove joints.
13. (canceled)
14. The method according to claim 2, wherein the welding is ultrasonic welding, and wherein the optical module and the frame are welded along joining surfaces which form shear joints.
15. (canceled)
16. (canceled)
17. The method according to claim 2, wherein the welding is done by laser beam welding, and wherein, for each optical module, one of the optical module or a connection portion of the frame adjacent the opening comprises a transparent portion, and the other one of the optical module and the connection portion comprises an opaque portion, said transparent portion and opaque portion being overlapped when the optical module is provided to the frame as seen in a direction substantially perpendicular to a plane of the opening; wherein the welding comprises using a beam to weld, for each optical module, the transparent portion to the opaque portion; and wherein preferably the transparent portion is included in the optical module and the opaque portion is included in the connection portion of the frame.
18. (canceled)
19. The method according to claim 2, wherein multiple optical modules are welded simultaneously, preferably using a single ultrasonic welding tool.
20. (canceled)
21. The method according to claim 2, wherein the at least one opening describes an array of at least two rows and two columns, and wherein the welding comprises welding four adjacent optical modules using a single circular motion of the laser beam.
22. (canceled)
23. (canceled)
24. (canceled)
25. (canceled)
26. The method according to claim 3, wherein, when assembling the plurality of optical modules to the frame, a pin of the plurality of pins is plastically reshaped over at least two of the plurality of optical modules.
27. (canceled)
28. An optical assembly comprising: a frame with at least one opening, preferably a plurality of openings, the at least one opening more preferably describing an array with a plurality of rows and a plurality of columns; a plurality of optical modules, each optical module of the plurality of optical modules being provided to an opening of the at least one opening; a support means provided to each of the plurality of optical modules and/or to each of the at least one opening, said support means being configured for supporting the optical module at least partially within the opening of the frame, wherein the support means is preferably integrally formed with the frame; wherein each optical module is assembled to the frame by plastically reshaping a material portion in contact with the frame and the optical module, the plastic reshaping occurring under an application of heat and/or pressure; and wherein, when the optical module is assembled to the frame, a first bottom surface of the optical module is substantially at a same level as a second bottom surface of the frame, said first bottom surfaces and second bottom surface being adapted for facing and being arranged on a support, such as a PCB, said support carrying a plurality of light sources; and optionally, wherein the plurality of optical modules comprises a plurality of lens element modules, each lens element module comprising at least one lens element, preferably a single lens element.
29. (canceled)
30. The optical assembly according to claim 28, further comprising a plurality of pins comprising a portion configured for being plastically reshaped under an application of heat and/or pressure to assemble the plurality of optical modules to the frame such that the plurality of optical modules are locked between the support means and the reshaped portions of the plurality of pins; and, optionally, wherein the pin is integrally formed with the frame or with the optical module, preferably integrally formed with the frame.
31. (canceled)
32. (canceled)
33. (canceled)
34. (canceled)
35. The optical assembly according to claim 28, wherein each opening in the frame is delimited by a peripheral wall with at least one protruding portion of the support means configured for supporting at least one peripheral portion of the optical module; preferably, wherein the at least one protruding portion is shaped as a peripheral step portion or wherein the at least one protruding portion comprises a peripheral wedge-shaped portion with a surface which is inclined with respect to a bottom surface of the and, preferably, wherein the at least one peripheral portion of the optical module has a shape which is substantially complementary to the shape of the at least one protruding portion.
36. (canceled)
37. (canceled)
38. (canceled)
39. (canceled)
40. The optical assembly according to claim 28, wherein the plurality of optical modules comprises four adjacent optical modules provided to four adjacent openings of the at least one opening, wherein a portion of the frame surrounded by the four adjacent openings is provided with a hole or a recess or a protrusion.
41. The optical assembly according to claim 28, wherein each opening has substantially the shape of a rectangle with cut-off corners.
42. (canceled)
43. The optical assembly according to claim 28, further comprising a support carrying a plurality of light sources, wherein the frame with the plurality of optical modules is arranged on the support so that each optical module is associated with one or more light sources of the plurality of light sources, wherein preferably each light source comprises one or more light emitting diodes with an optional primary optical element, e.g a primary lens.
44. (canceled)
45. The optical assembly according to claim 30, wherein, for each opening and optical module paired, at least one recess is provided to the optical module and/or to a surface adjacent to the opening, said at least one recess being configured for receiving a portion of the pin.
46. (canceled)
47. (canceled)
48. The optical assembly according to claim 28, wherein the support means comprises at least one tab extending substantially parallel to a plane of the at least one opening of the frame, preferably inwardly inside the at least one opening.
49. (canceled)
50. (canceled)
51. (canceled)
52. The optical assembly according to claim 30, wherein the reshapable portion of the pin is protruding outwardly when the optical module is provided to the opening, preferably in an upward direction when the frame is positioned on a bottom surface intended to face a support carrying light sources.
53. (canceled)
54. (canceled)
Description
BRIEF DESCRIPTION OF THE FIGURES
[0241] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing a currently preferred embodiment of the invention. Like numbers refer to like features throughout the drawings.
[0242] FIG. 1 is a schematic perspective view of an exemplary embodiment of an optical assembly;
[0243] FIG. 2 is a schematic exploded perspective view of the exemplary embodiment of FIG. 1;
[0244] FIG. 3 is a partially cut perspective view of the frame and optical modules of the exemplary embodiment of FIG. 1, in a position in which the welding takes place;
[0245] FIG. 3A is a detailed view of FIG. 3 illustrating the welding process;
[0246] FIG. 4 is a cross-section of an alternative embodiment of an optical assembly with a frame in which optical modules are welded ultrasonically to the frame;
[0247] FIGS. 5A-5C are cross-sections similar to the cross-section of FIG. 4 for alternative embodiments using ultrasonic welding;
[0248] FIG. 6 is a schematic perspective view of another exemplary embodiment of an optical assembly;
[0249] FIG. 7 is a schematic exploded perspective view of the exemplary embodiment of FIG. 6;
[0250] FIG. 8 is a partially cut perspective view of the frame and optical modules of the exemplary embodiment of FIGS. 5;
[0251] FIG. 9 is a detailed view of an optical module of the embodiment of FIG. 6;
[0252] FIG. 10 illustrates the selecting of optical modules in accordance with an embodiment of the method;
[0253] FIG. 11 illustrates a flow chart of an exemplary embodiment of a method for assembling optical modules;
[0254] FIGS. 12A-12B are schematic perspective views from the top side and from the bottom side, respectively, of an exemplary embodiment of an optical assembly;
[0255] FIG. 13 illustrates schematically a perspective view of an exemplary embodiment of a lighting system;
[0256] FIG. 14 is a schematic exploded perspective view of a lighting system with the exemplary embodiment of FIG. 13;
[0257] FIGS. 15A-15B are partially cut perspective views of the frame of the exemplary embodiment of FIGS. 13 and 14;
[0258] FIGS. 16A-16B are close-up views of the optical module of the exemplary embodiment of FIGS. 13 and 14;
[0259] FIG. 17 is a partially cut perspective view of the frame according to another exemplary embodiment;
[0260] FIG. 18 illustrates the selecting of optical modules in accordance with an embodiment of the method;
[0261] FIG. 19 illustrates a flow chart of an exemplary embodiment of a method for assembling optical modules;
[0262] FIG. 20 illustrates yet another exemplary embodiment of an optical assembly suitable for ultrasonic welding.
DESCRIPTION OF THE FIGURES
[0263] FIGS. 1, 2 and 3 illustrate an optical assembly 1000 comprising a frame 100 with a plurality of openings 110, a plurality of optical modules 210 arranged in the frame 100, and a support 300 with a plurality of light sources 310, e.g. light emitting diodes optionally provided with a primary optics. Each optical module 210 is provided to a corresponding opening of the plurality of openings, and each optical module 210 is welded to the frame 100. Optionally multiple optical modules 210 may be arranged in a single opening 110. The openings 110 are shown to have the same shapes and sizes, but the frame may also be provided with openings having a different shape and/or size. More generally, the optical modules 210 may be the same or different and/or the openings 110 may be the same or different. Preferably, the openings 110 are the same and the optical modules 210 are the same or different but all fit in the same openings 110. Preferably, the plurality of openings 110 describes an array with a plurality of rows and a plurality of columns.
[0264] The frame 100 with the plurality of optical modules 210 is arranged on the support 300 so that each optical module is associated with one or more light sources 310 of the plurality of light sources 310. Preferably each light source comprises one or more light emitting diodes with an optional primary optical element, e.g. a primary lens.
[0265] In the illustrated example, the plurality of optical modules 210 is a plurality of lens modules, each lens module comprising a single free-form lens element 240. The lens element 240 comprises a lens portion having an outer surface 241 and an inner surface 242 intended to face an associated light source, wherein the outer surface 241 comprises a convex surface and the inner surface 242 comprises a concave surface joining the flat bottom surface 215. However, as described in the summary, embodiments may comprise any type of optical modules and a module can comprise one or more optical elements.
[0266] A peripheral edge portion 211 of the optical module 210 is welded to the frame 100, see FIGS. 3 and 3A. Preferably, the optical module 210 is made integrally of a transparent material. The optical module may be made of a material comprising any one of the following or a combination thereof: poly-methyl methacrylate (PMMA), polycarbonate (PC), and the frame 100 may be made of a material comprising any one of the following or a combination thereof: acrylonitrile butadiene styrene (ABS), polybutylene terephthalate (PBT), polycarbonate (PC), poly-methyl methacrylate (PMMA). Optionally the frame 100 may comprise reinforcement fibers. In a preferred embodiment the frame may be made of polybutylene terephthalate (PBT) or a mixture of polycarbonate (PC) and acrylonitrile butadiene styrene (ABS).
[0267] The optical module 210 has a flat bottom surface 215, and preferably the bottom surface 215 is substantially at a same level as a second bottom surface 115 of the frame. The bottom surfaces 115, 215 are adapted for being arranged on a support 300, such as a PCB.
[0268] Each opening 110 in the frame 100 is delimited by a peripheral wall with at least one protruding portion 111 of a support means configured for supporting at least one peripheral portion 211 of the optical module. Preferably, the at least one peripheral portion 211 of the optical module 210 has a shape which is substantially complementary to the shape of the at least one protruding portion 111. In the embodiment of FIGS. 1-3, the at least one protruding portion 211 of the support means is shaped as a peripheral step portion, and the full periphery of the peripheral step portion 211 may be welded. Alternatively, only straight lines, see arrows A1, may be welded, or only a circular line C may be welded.
[0269] The plurality of optical modules 210 comprises four adjacent optical modules provided to four adjacent openings 110, and a portion of the frame 100 surrounded by the four adjacent openings 100 is provided with a hole 131 or a recess 132 or a protrusion 133. The holes 131 may be intended for receiving a fixation means 31 such as a bolt or a screw. The protrusions 133 and/or recesses 132 may be used e.g. for alignment or indication purposes. As illustrated, each opening 110 may have substantially the shape of a rectangle with cut-off corners, such that additional space is available for forming a hole 131 or a recess 132 or a protrusion 133 in between four corners.
[0270] FIG. 3A illustrates welding using a laser beam B, but the welding could also be done using an ultrasonic welding head. FIG. 4 illustrates an alternative embodiment where ultrasonic welding by an ultrasonic welding tool T is used. The optical module 210 and the frame 100 are welded along joining surfaces 116, 216, and at least one surface of the joining surfaces 116, 216 is provided with an energy director 217 configured to concentrate ultrasonic energy and to initiate melting during the welding. In figure the joining surfaces form butt joints. As illustrated in FIGS. 5A and 5B the joining surfaces may also form step joints or tongue and groove joints. FIG. 5C illustrates a further embodiment where the welding is ultrasonic welding, and the optical module 210 and the frame 100 are welded along joining surfaces 118, 218 which form shear joints.
[0271] FIGS. 6, 7, 8 and 9 illustrate another exemplary embodiment of an optical assembly suitable for ultrasonic welding. The same or similar components have been indicated with the same reference numerals as in the previous figures. In this embodiment, the optical modules 210 each comprise a lens element 240 and a backlight element 250. The optical module 210 and the frame 100 are welded along joining surfaces 116, 216, and at least one surface of the joining surfaces 116, 216 is provided with an energy director 217 configured to concentrate ultrasonic energy and to initiate melting during the welding. As can be seen in FIGS. 8 and 9 the outer periphery of the optical modules is provided with a stepped portion 211, and an energy director 217 is provided on the stepped portion 211 in a similar manner as in FIG. 4. As illustrated the energy director 217 may have an outer wall 217a directed perpendicular on the bottom surface 215 of the optical module and an inclined inner 217b which is oriented at an angle, preferably such that a top angle of the energy director 217 is between 20° and 70°. In other embodiments both the outer and inner wall of the energy director may be oriented at an angle different from 90° with respect to the bottom surface 215.
[0272] FIG. 20 illustrates yet another exemplary embodiment of an optical assembly suitable for ultrasonic welding. In this embodiment, an opening 110′ in a frame 100′ may be dimensioned to receive a plurality of optical modules (not shown) one next to the other. Optionally, at least two optical modules may be assembled together using interlocking mechanical means, glue, and/or by magnetic force. In the embodiment of FIG. 20, there are two elongated openings 110′ in the frame 100′ which are designed each for a column of optical modules, preferably of four optical modules. The optical modules and the frame 100′ are welded along joining surfaces 116′ acting as support means, and at least one surface of the joining surfaces 116′ is provided with an energy director 117′ configured to concentrate ultrasonic energy and to initiate melting during the welding. As can be seen in FIG. 20, outer peripheries of the openings 110′ are provided with a plurality of energy directors 117′, preferably having a triangular profile. The plurality of energy directors 117′ are provided in an interrupted manner on each side along the length of the openings 110′. The skilled person will understand that the plurality of energy directors 117′ may also be provided to a step portion of the outer peripheries similarly as in the embodiments described with respect to FIGS. 4, 5A-5C. Additionally, a hole 131′ between the openings 110′ may be provided in the frame 100′ and intended for receiving a fixation means such as a bolt or a screw.
[0273] FIGS. 10 and 11 illustrate schematically an exemplary embodiment of a method for assembling optical modules 210a, 210b, 210c. As illustrated in FIG. 11, the method comprises the following steps. In a first step 11 digital data representative for the optical modules to be included in the frame is received. In a second step 12, based on the received digital data in step 11, the plurality of optical modules is selected from a storage 2a, 2b, 2c comprising multiple different optical modules 210a, 210b, 210c, and placed in a frame 100 with at least one opening 110, see also FIG. 10. This picking and placing may be done automatically using a robotic arm controlled by a computing means based on the received digital data, but could also be done partially manually. The plurality of optical modules 210a, 210b, 210c is provided to the frame 100 such that each optical module of the plurality of optical modules is provided to an opening 110 of the plurality of openings 110. In the embodiment of FIG. 10, each opening 110 is provided with one optical module 210, but one could also have an opening 110 with a size which is a multiple of the size of the optical module 210 so that multiple optical modules can be arranged in a single opening 110. In a third step 13, the welding is performed. As explained above, the welding may be ultrasonic welding or laser beam welding or any other suitable welding technique. The welding may consist in welding one or more subsets S1, S2 of optical modules 210a, 210b, 210c simultaneously using one or more welding heads. For example a first subset S1 may be welded with a first welding head and a second subset S2 may be welded simultaneously with a second welding head. The subsets S1, S2 are shown to be columns in FIG. 10 but can be any group of optical modules, e.g. arrays of 2×2 optical modules or rows of optical modules, or arrays of 2×1 or 2×3 optical modules, etc.
[0274] FIGS. 12A-12B are schematic perspective views from the top side and from the bottom side, respectively, of an exemplary embodiment of an optical assembly according to the present invention.
[0275] The optical assembly 500 comprises: a frame 510, a plurality of optical modules 520, a support means 530, and a plurality of pins 540. The optical assembly 500 may be included in a luminaire system.
[0276] The luminaire system typically comprises a luminaire head with a luminaire housing and optionally a luminaire pole. The luminaire head may comprise a supporting substrate, e.g. a PCB and at least one optical assembly, e.g. lens plates. The luminaire head may be connected in any manner known to the skilled person to the luminaire pole. Typical examples of such systems are street lights. In other embodiments, a luminaire head may be connected to a wall or a surface, e.g. for illuminating buildings or tunnels. In yet other embodiment, the luminaire head may be connected to catenary cables.
[0277] Preferably, the luminaire is an outdoor or industrial luminaire. By outdoor or industrial luminaires, it is meant luminaires which are installed on roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths or in pedestrian zones, for example, and which can be used notably for the lighting of an outdoor area or a large indoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouses, industry halls, etc.
[0278] As can be seen in FIGS. 13 and 14, a support structure may comprise the supporting substrate 550, e.g. a PCB, and a heat sink (not shown) onto which the supporting substrate 550 may be mounted, said heat sink being made of a thermally conductive material, e.g. aluminium. Alternatively, the PCB may be mounted directly on the luminaire housing functioning as heat sink. A plurality of light sources 555 may be provided to the supporting substrate 550. The plurality of light sources 555 may comprise a plurality of LEDs. Further, each light source 555 may comprise a plurality of LEDs, more particularly a multi-chip of LEDs. The plurality of light sources 555 may be arranged without a determined pattern or in an array with at least two rows of light sources 555 and at least two columns of light sources 555, typically an array of more than two rows and more than two columns, an array of five rows by four columns in the embodiments of FIGS. 13 and 14. The surface onto which the plurality of light sources 555 is mounted can be made reflective or white to improve the light emission. The plurality of light sources 555 could also be light sources other than LEDs, e.g. halogen, incandescent, or fluorescent lamps.
[0279] Further, the light sources 555 may be similar or may have different colours or different colour temperatures. Additionally, each light source 555 may be associated with one or more optical elements (e.g. a lens and/or a reflector), or a number of light sources 555 may share one or more optical elements (e.g. one reflector and/or one lens and/or one diffusor for multiple light sources)
[0280] In FIGS. 12A-12B, each optical module 510 may comprise one or more optical elements, typically lens elements 521, associated with the plurality of light sources. Indeed, lens elements may be typically encountered in outdoor or industrial luminaire systems, although other types of optical elements may be additionally or alternatively present in such luminaires, such as reflectors, backlights, prisms, collimators, diffusors, and the like. The plurality of optical elements may be mounted such that each of the plurality of light sources is arranged opposite an optical element. In the exemplary embodiment shown in FIGS. 12A-12B, the optical elements are lens elements 521 which are similar in size and shape and there is one lens element 521 planned for each light source. Each lens element 521 comprises a concave surface configured for facing a corresponding light source, and a convex surface opposite the concave surface. The lens element 521 may be a secondary lens element while the corresponding light source may be provided with a primary lens element.
[0281] In another exemplary embodiment, some or all of the optical elements may be different from each other. In a further exemplary embodiment, there may be more optical elements than light sources, and the frame provided with the optical modules 510 may be movable such that a light source can be moved from a position opposite a first optical element to a position opposite a second optical element. In other embodiments, there may be provided a plurality of LEDs opposite some or all of the optical elements. The lens elements 521 may be in a transparent or translucent material. They may be in optical grade silicone, glass, poly(methyl methacrylate) (PMMA), polycarbonate (PC), or polyethylene terephthalate (PET), ABS, or PBT, preferably PMMA.
[0282] The optical elements may each be surrounded by a mounting portion 522. The mounting portion 522 may be configured for mounting the optical module 520 within a corresponding opening 511 of the frame. The mounting portion 22 and the optical element may be integrally formed. The mounting portion 522 in FIGS. 12A-12B comprises a plate surrounding the lens element 521 of the optical module with an upper flat surface 522a and a bottom flat surface 522b opposite the upper flat surface 522a, said bottom flat surface 522b facing a light source in a mounted state of the optical assembly 500.
[0283] The frame 510 comprises at least one opening 511, a plurality of openings 511 in the embodiments of FIGS. 12A-12B. At least one optical module 520 of the plurality of optical modules is provided per opening 511 of the plurality of openings. In the embodiment of FIGS. 12A-12B, there is one optical module 520 provided per opening 511. In another embodiment, there may be a plurality of optical modules provided per opening such that the plurality of optical modules fills the corresponding opening. More generally, the optical modules 520 may be the same or different and/or the openings 511 may be the same or different. Preferably, the openings 511 are the same and the optical modules 520 are the same or different but all fit in the same openings 511. Preferably, the plurality of openings 511 describes an array with a plurality of rows and a plurality of columns.
[0284] The frame 510 may be in an opaque, transparent, or translucent material, preferably in a transparent material. It may be in ABS, PBT, PMMA, PC, or a combination thereof. In a preferred embodiment the frame may be made of polybutylene terephthalate (PBT) or a mixture of polycarbonate (PC) and acrylonitrile butadiene styrene (ABS).
[0285] The plurality of openings 520 may be arranged in an array, an array of two lines by two columns in the embodiment of FIGS. 12A-12B. The support means 530 is provided to each of the plurality of optical modules 520 and/or to each of the plurality of openings 511. The support means 530 is configured for supporting the optical module 520 at least partially within the opening 511 of the frame. In an embodiment, the optical module 520 may be supported at least partially within the opening 511 using glue. In another embodiment, the optical module 520 may be supported at least partially within the opening 511 using magnetic forces. Preferably, the support means 530 is a mechanical support means. In the embodiment of FIGS. 12A-12B, the support means 530 comprises elements 531, 534 integrally formed with the optical module 520 and elements 532, 533 integrally formed with the frame 510.
[0286] The support means 530 may be configured such that, when the optical module 520 is assembled to the frame 510, the bottom surface 522b of the optical module is substantially at a same level as a bottom surface 512b of the frame, said bottom surface 522b of the optical module and bottom surface 512b of the frame being adapted for facing a plurality of light sources. One can thus obtain an optical assembly 600 with a flush bottom side which allows for an accurate placement of the optical assembly 600 over light sources against the supporting substrate.
[0287] The support means 530 may comprise at least one tab 533 extending substantially parallel to a plane of the opening 511 of the frame. In the embodiment of FIGS. 12A-12B, the support means 530 comprises a plurality of tabs 533 which extends inwardly inside the opening 511. There may be two tabs 533 in diametrical opposition of one another. In another embodiment, there may be only one tab, a peripheral tab to the opening 511 for example. In yet another embodiment, there may be more than two tabs. By extending inwardly, the plurality of tabs 533 may prevent the optical module 520 to fall through the corresponding opening 511. Indeed a distance between extremities of the tabs 533 is less than a corresponding longitudinal distance of the bottom surface 522b of the optical module.
[0288] In the embodiment of FIGS. 12A-12B, the plurality of tabs 533 may be configured for being provided to a plurality of complementary indents 34 formed in the optical module 520. More particularly, the tabs 533 may extend in prolongation of the bottom surface 512b of the frame, and the complementary indents 534 may be formed in the bottom surface 522b of the optical module such that, when the optical module 520 is arranged at least partially within the opening, the bottom surface 512b of the frame and the bottom surface 522b of the optical module are flush with each other.
[0289] In the embodiment of FIGS. 12A-12B, the upper surface 512a of the mounting portion is provided with a plurality of tongues 531. The plurality of tongues 531 may extend substantially parallel to the plane of the opening 511 of the frame. The plurality of tongues 531 may extend in prolongation of the upper surface 522a of the optical module. In the embodiment of FIGS. 12A-12B, there may be two tongues 531 in diametrical opposition of one another. In another embodiment, there may be only one tongue. In yet another embodiment, there may be more than two tongues. By extending outwardly, the plurality of tongues 531 may prevent the optical module 520 to fall through the corresponding opening 511. Indeed a distance between extremities of the tongues 531 is more than a corresponding lateral distance of the upper surface 512a of the optical module.
[0290] The plurality of tongues 531 may be received in a corresponding plurality of indents 532 formed in the upper surface 512a of the frame. The skilled person will understand that either of the plurality of tongues 531 or the plurality of tabs 533 are sufficient on their own as the support means 530.
[0291] In the embodiment of FIGS. 12A-12B, the plurality of optical modules 520 comprises four adjacent optical modules 520 provided to four adjacent openings 511 of the plurality of openings. A portion of the frame surrounded by the four adjacent openings 511 may be provided with a hole or a recess or a protrusion, a through-hole 513 in the present embodiment. The through-hole 513 may be adapted for a fixation means (not shown) configured for fixing the optical assembly 600 to the support structure. Additionally, each opening 511 may have substantially the shape of a rectangle with cut-off corners. In that manner additional space is provided for arranging a hole or a recess or a protrusion as required. The plurality of tongues 531 and the plurality of tabs 533 may be located on different sides of the rectangular shape of the opening; thereby insuring a stable support of the optical module 520.
[0292] The plurality of pins 540 comprises each a portion 541 configured for being plastically reshaped under an application of heat and/or pressure to assemble the plurality of optical modules 520 to the frame 510. The reshapable portion 541 may be located at one or more ends of the pin 540. In an embodiment, the plurality of pins 540 may be arranged at the periphery of optical modules 520 such that, when reshaped, the reshapable portion 541 of the pin overlaps the frame 510 and the optical module 520. In another embodiment the plurality of pins 540 is integrally formed with the optical module 520 and the reshapable portion 541 of each pin overlaps, when reshaped, the frame 510. There may be one or more pins 540 per optical module 520 to achieve the assembly with the frame 510. In an embodiment, one pin may be used to assemble a plurality of optical modules by overlapping, when reshaped, over at least two optical modules and/or the frame. In the embodiment, of FIGS. 12A-12B, the plurality of pins 540 is integrally formed with the frame 510 and extends through corresponding through-holes in the tongues 531. The reshapable portion 541 of each pin 540 overlaps, when reshaped, the corresponding optical module 520.
[0293] When providing the plurality of pins 540 to the plurality of optical modules 520, at least one optical module 520 of the plurality optical modules being at least partially arranged within each opening 511 of the plurality of openings, each of the reshapable portions 541 may protrude from the upper surface 522a of the optical module, the upper surface 512a of the frame, the bottom surface 522b of the optical module, and/or the bottom surface 512b of the frame.
[0294] For each opening 511 and optical module 520 paired, at least one recess may be provided to the optical module 520 and/or to a surface adjacent to the opening 511, said at least one recess being configured for receiving a portion of the pin 540. In the embodiment of FIGS. 12A-12B, one recess is provided to each of the plurality of tongues 531. The recess is a through-hole through a tongue 531. Each pin 540 is extending, upwardly, away from the indent 532 in the upper surface 512a of the frame. Thus, the plurality of tongues 531 comprises each a peripheral surface of the at least one recess configured as the support means 530 for supporting the corresponding optical module 520 at least partially within the opening 511 of the frame. The reshapable portion 541 of each pin may be protruding out of the recess.
[0295] FIG. 13 illustrates schematically a perspective view of an exemplary embodiment of a lighting system according to the present invention. FIG. 14 illustrates schematically an exploded view of the exemplary embodiment of FIG. 13. The lighting system 1500 comprises a support structure 550 and an optical assembly 700. The optical assembly 700 comprises: a frame 710, a plurality of optical modules 720, a support means 731, 732, and a plurality of pins 740. The optical assembly 700 comprises a plurality of optical modules 720 arranged in an array, an array of five rows by four columns in the present embodiment.
[0296] In the embodiment of FIG. 14, a plurality of light sources 555 is arranged on the support structure 550, each of the plurality of light sources corresponding to one optical module 720 of the plurality of optical modules. The support structure 550 may comprise one or more PCBs. For convenience, the support structure 550 is shown in FIGS. 13 and 14 as a single plate, but the skilled person understands that the support structure 550 may also be formed with a plurality of PCBs.
[0297] The optical modules 720 of FIGS. 13 and 14 may comprise lens modules comprising each a lens element 721. The plurality of optical modules 720 may all be similar or there may be different optical modules. Further, it should be clear for the skilled person that the plurality of optical modules 720 may additionally or alternatively comprise other elements than lens elements 721, such as reflectors, backlight elements, collimators, diffusors, and the like, backlight elements 722 in the present embodiment. FIGS. 16A-16B are close-up views of the optical module of the exemplary embodiment of FIGS. 13 and 14.
[0298] The lens element 721 may be free form in the sense that it is not rotation symmetric. In the embodiments of FIGS. 13 and 14, the lens elements 721 have a symmetry axis. In another embodiment, the lens elements may have no symmetry plane/axis. Each optical module 720 may be moulded in a transparent or translucent material. The optical modules 720 may be e.g. in optical grade silicone, glass, poly(methyl methacrylate) (PMMA), polycarbonate (PC), or polyethylene terephthalate (PET), ABS, PBT, or a combination thereof, preferably in PMMA. Optionally a reflective coating may be provided on a portion of the optical module 720.
[0299] FIGS. 15A-15B are partially cut perspective views of the frame of the exemplary embodiment of FIGS. 13 and 14. A portion of the frame surrounded by four adjacent openings 711 may be provided with a hole or a recess or a protrusion, a through-hole 713 in the present embodiment. The through-hole 713 may be adapted for a fixation means (now shown in FIG. 15A but may be similar to the fixation means 714 in FIG. 14) configured for fixing the optical assembly 700 to the support structure 550 or to an element of the support structure 550 below the PCB of the support structure 550. Additionally, each opening 711 may have substantially the shape of a rectangle with cut-off corners. In that manner additional space is provided for arranging a hole or a recess or a protrusion as required.
[0300] The support means 731, 732 of FIGS. 13 and 14 may comprise at least one tab extending substantially parallel to a plane of the opening 711 of the frame. The at least one tab 732 may extend inwardly inside the opening 711 around a periphery of the opening 711. By extending inwardly, the peripheral tab 732 may prevent the optical module 720 to go through the corresponding opening 711. Indeed a distance between opposite extremities of the peripheral tab 732 may be less than a corresponding longitudinal distance of a bottom surface 723b of the optical module 720. The peripheral tab 732 may be configured for being provided to a complementary peripheral indent 731 formed in the optical module 720. More particularly, the peripheral tab 732 may extend in prolongation of the upper surface 712a of the frame 710, and the complementary peripheral indent 731 may be formed in the upper surface 723a of the optical module 720 such that, when the optical module 720 is arranged at least partially within the opening 711, the upper surface 712a of the frame 710 and the upper surface 723a of the optical module 720 are flush with each other. In another embodiment, the support means comprises a plurality of tabs extending inside the opening 711.
[0301] The plurality of pins 740 comprises each a portion 741 configured for being plastically reshaped under an application of heat and/or pressure to assemble the plurality of optical modules 720 to the frame 710. The reshapable portion 741 may be located at one end of the pin 740, at an ends of the pin 740 opposite the peripheral tab 732 in the embodiments of FIGS. 13 and 14. The plurality of pins 740 may be arranged at the periphery of optical modules 720 such that, when reshaped, the reshapable portions 741 of the pins overlap the frame 710 and the optical module 720. In the embodiments of FIGS. 13 and 14 the plurality of pins 740 is separately formed from the frame 710, and the reshapable portions 741 of each pin overlap, when reshaped, the optical module 720 and, optionally, the frame 710. In another embodiment, the plurality of pins may be integrally formed with the frame. Additionally or alternatively, the plurality of pins may comprise more than one reshapable portion.
[0302] There may be one or more pins 740 per optical module 720 to achieve the assembly with the frame 710, two pins 740 per opening 711 in the embodiments of FIGS. 13 and 14. When providing the plurality of optical modules 720 to the plurality of openings 711, each of the reshapable portions 741 of the pins may, respectively, protrude from an upper surface 723a of the optical module and an upper surface 712a of the frame, and protrude from a bottom surface 723b of the optical module and a bottom surface 712b of the frame.
[0303] For each opening 711 and optical module 720 paired, at least one recess 724 may be provided to the optical module 720 and/or to a surface adjacent to the opening 711, said at least one recess 724 being configured for receiving a portion of the pin 740. In the embodiments of FIGS. 13 and 14, the at least one recess 724 is provided to a side surface of the optical module 720; more particularly two recesses 724 located in diametrical opposition are provided to each side of the optical module 720.
[0304] To reshape the plurality of pins 740, a tool with a heated head may be applied on each reshapable portion 741. The shape of the heated head may define the reshaped form of the pin 740. Indeed, under the application of heat and/or pressure, the reshapable portion 741 will complement the shape of the reshaping head applied to it. In an embodiment, the reshaping head may comprise a semi-spherical cavity and the reshapable portion 741 will be reshaped as a semi-sphere. In another embodiment, the reshaping head may comprise an elongated cavity and the reshapable portion 741 will be reshaped accordingly.
[0305] Preferably, the reshaped form of the pin 740 extends along and/or across the periphery of the optical module 720. During assembly, the heated head may be configured to apply heat at a temperature above the glass transition temperature of the reshapable portion 741. More than one reshapable portion 741 may be reshaped at once by the tool. For example, the tool may reshape at once two adjacent pins 740. In the embodiments of FIGS. 13 and 14, the tool may be configured for reshaping five pairs of adjacent pins 740 organized in one column at once.
[0306] FIG. 14 is a schematic exploded perspective view of a lighting system similar to the exemplary embodiment of FIG. 13 according to the present invention. The lighting system 1500 comprises the supporting substrate 550 and the optical assembly 700. The optical assembly 700 comprises: the frame 710, the plurality of optical modules 720, the support means 731, 732, and the plurality of pins 740. The optical assembly 700 comprises the plurality of optical modules 720 arranged in an array, an array of five rows by four columns in the present embodiment. Each of the plurality of optical modules 720 is similar to the optical modules 720 of FIG. 13.
[0307] In the embodiment of FIG. 14, the plurality of light sources 555 is arranged on the supporting substrate 550, each of the plurality of light sources 555 corresponding to one optical module 720 of the plurality of optical modules. The plurality of light sources 555 may be provided to a PCB and the supporting substrate 50 may comprise a heat sink (not shown) in thermal contact with the PCB.
[0308] To assemble the optical assembly 1500, the frame 710 may be provided upside down to an assembly line. An upside face of the frame 710 may correspond to a face in a direction opposite to a plurality of light sources 555 when the optical module 720 is assembled to the frame 710. The plurality of optical modules 720 may then be provided to the frame 710, followed by the plurality of pins 740 through the recesses 724 of each optical module. The plurality of pins 740 may be inserted in the recesses 724 by force. After inserting the plurality of pins 740, both ends of each pin 740 may protrude from, respectively the top face of the frame 710 and the bottom face of the frame 710. In the embodiment of FIG. 14, the end of the pin opposite the plurality of light sources 555 is the reshapable portion 741 of the pin. In another embodiment, both ends may be reshapable portions of the pin.
[0309] These reshapable portions 741 may be reshaped under the application of heat and/or pressure by a specific tool. Depending on embodiments, a plurality of reshapable portions 741 may be reshaped simultaneously. For example, both reshapable portions of a pin comprising two reshapable ends may be reshaped simultaneously. In another embodiment, a plurality of reshapable portions 741 protruding from one side of the frame 710 is reshaped simultaneously.
[0310] After assembly of the optical assembly 1500, the optical assembly 1500 may be provided to the supporting substrate 50, and the optical assembly and the supporting substrate 550 may be fixed together using the fixation means 714 passing through the through-hole 713 of the frame. When providing the optical assembly 1500 to the supporting substrate 550, the frame 710 may be positioned in a preset position using a positioning protrusion 715 as can be seen in FIG. 15B configured for cooperating with a corresponding positioning indent 715′ of the supporting substrate as can be seen in FIG. 14.
[0311] FIG. 17 is a partially cut perspective view of the frame according to another exemplary embodiment of the present invention.
[0312] A frame 1110 may comprises at least one opening 1111, a plurality of openings 1111 in the embodiment of FIG. 17. A plurality of pins 1140 comprises each a portion 1141 configured for being plastically reshaped under an application of heat and/or pressure to assemble a plurality of optical modules 1120 to the frame 1110. The reshapable portion 1141 may be located at one end of the pin 1140. The plurality of pins 1140 may be arranged at the periphery of optical modules such that, when reshaped, the reshapable portion 1141 of the pin overlaps the optical module and, optionally, the frame 1110 optical module. In the embodiment of FIG. 17 the plurality of pins 1140 is integrally formed with the frame 1110 and each of the pins 1140 is extending upwardly away from the frame 1110. There may be one or more pins 1140 per optical module to achieve the assembly with the frame 1110, two pins 1140 per opening 1111 in the embodiment of FIG. 17. To accommodate the plurality of pins 1140, the optical module may comprise at least one corresponding recess 1124. The at least one recess 1124 may be provided to a side surface of the optical module 1120; there are two recesses 1124 diametrically located for each optical module 1120 of FIG. 17.
[0313] When providing the plurality of optical modules to the plurality of openings 1111, each of the reshapable portions 1141 of the pins may protrude from an upper surface 1112a of the frame. A support means 1130 of FIG. 17 may comprise at least one tab, a plurality of tabs 1133 in FIG. 17, extending substantially parallel to a plane of the opening 1111 of the frame. The plurality of tabs 1133 may extend inwardly inside the opening 1111. Each of the plurality of pins 1140, when the optical module 1120 is assembled to the frame, may be located at substantially 90° with respect to the support means 1130 as seen in the plane of the opening 1111. In the embodiment of FIG. 17, there may be two tabs 1133 in diametrical opposition of one another and two pins 1140 in diametrical opposition of one another per opening 1111, and the plurality of pins 1140 is aligned in a direction at substantially 90° with respect to an alignment of the plurality of tabs 1133. By extending inwardly, the plurality of tabs 1133 may prevent the optical module 1120 to fall through the corresponding opening 1111. More particularly, the tabs 1133 may extend in prolongation of a bottom surface of the frame 1110.
[0314] In an embodiment, the plurality of optical modules 1120 may comprise at least one indent complementary to the at least one tab 1133 of the frame. The complementary indent may be configure such that, when the optical module is assembled to the frame, a first bottom surface of the optical module is substantially at a same level as a second bottom surface of the frame, said first bottom surfaces and second bottom surface being adapted for facing a plurality of light sources. In another embodiment, the plurality of optical modules 1120 may not comprise the at least one complementary indent.
[0315] FIGS. 18 and 19 illustrate schematically an exemplary embodiment of a method for assembling optical modules 720a, 720b, 720c. As illustrated in FIG. 19, the method comprises the following steps. In a first step S11 digital data representative for the optical modules to be included in the frame is received. In a second step S12, based on the received digital data in step S11, the plurality of optical modules is selected from a storage 2a, 2b, 2c comprising multiple different optical modules 720a, 720b, 720c, and placed in a frame 710 with a plurality of openings 711, see also FIG. 19. This picking and placing may be done automatically using a robotic arm controlled by a computing means based on the received digital data, but could also be done partially manually. The plurality of optical modules 720a, 720b, 720c is provided to the frame 710 such that each optical module of the plurality of optical modules is provided to a corresponding opening 711 of the plurality of openings 711. In the embodiment of FIG. 19, each opening 711 is provided with one optical module 720, but one could also have an opening 711 with a size which is a multiple of the size of the optical module 720a, 720b, 720c so that multiple optical modules can be arranged in a single opening 711. In a third step S13, the reshaping for locking the plurality optical modules between the support means and the plurality of reshaped pins is performed. As explained above, the reshaping may be achieved by a tool with a reshaping head. The reshaping head of the tool may be configured for applying heat and/or pressure and may be designed to reshape the reshapable portion of the pin following a preset form. Indeed, under the application of heat and/or pressure, the reshapable portion will complement the shape of the reshaping head applied to it. In an embodiment, the reshaping head may comprise a semi-spherical cavity and the reshapable portion will be reshaped as a semi-sphere. In another embodiment, the reshaping head may comprise an elongated cavity and the reshapable portion will be reshaped accordingly. The reshaping may consist in reshaping to lock in place one or more subsets S1, S2 of optical modules 720a, 720b, 720c simultaneously using one or more reshaping heads. For example a first subset S1 may be locked thanks to a first reshaping head and a second subset S2 may be locked simultaneously thanks to a second reshaping head. The subsets S1, S2 are shown to be columns in FIG. 19 but can be any group of optical modules, e.g. arrays of 2×2 optical modules or rows of optical modules, or arrays of 2×1 or 2×3 optical modules, etc.
[0316] Whilst the principles of the invention have been set out above in connection with specific embodiments, it is to be understood that this description is merely made by way of example and not as a limitation of the scope of protection which is determined by the appended claims.
