Vehicle light assembly comprising flexible lighting strip

Abstract

A vehicle light assembly comprising: a flexible lighting strip comprising a multitude of light-emitting diodes, wherein the flexible lighting strip is arranged to be bent around at least two, more preferred three linear independent axes; a light guiding structure comprising a light receiving surface and a primary light emission surface, wherein the light receiving surface receives light emitted by the flexible lighting strip, wherein the primary light emission surface emits at least a part of the light received via the light receiving surface, and wherein the light receiving surface is arranged to define a bending of the flexible lighting strip; a coupling structure that is arranged to mechanically couple the flexible lighting strip to the light receiving surface in accordance with the bending defined by the light receiving surface. The invention further describes a vehicle rear light or vehicle front light comprising the vehicle light assembly.

Claims

1. A vehicle light assembly comprising: a flexible lighting strip comprising a multitude of light-emitting diodes, wherein the flexible lighting strip is arranged to be bended around at least two, more preferred three linear independent axes; a light guiding structure comprising a light receiving surface and a primary light emission surface, wherein the light receiving surface is arranged to receive light emitted by the flexible lighting strip, wherein the primary light emission surface is arranged to emit at least a part of the light received via the light receiving surface, and wherein the light receiving surface is arranged to define a bending of the flexible lighting strip, wherein the light guide further comprising a secondary light emission surface, and wherein the secondary light emission surface is arranged to emit at least a part of the light received via the light receiving surface, wherein the primary light emission surface is arranged to provide a higher luminance than the secondary light emission surface; a coupling structure, wherein the coupling structure is arranged to mechanically couple the flexible lighting strip to the light receiving surface in accordance with the bending defined by the light receiving surface, wherein the coupling structure is flexible, and wherein the coupling structure is a separate structure which comprises a mechanical coupling surface for receiving the flexible lighting strip and a fixing structure for fixing the coupling structure such that the flexible lighting strip is arranged between the mechanical coupling surface and the light receiving surface.

2. The vehicle light assembly according to claim 1, wherein the light guiding structure comprises a light guide comprising at least a part of the light receiving surface and at least a part of the primary light emission surface.

3. The vehicle light assembly according to claim 1, wherein the light guiding structure comprises a reflective structure, wherein the reflective structure comprises at least a part of the light receiving surface and at least a part of the primary light emission surface.

4. The vehicle light assembly according to claim 1, wherein the light guiding structure comprises a scattering structure, wherein the scattering structure comprises at least a part of the light receiving surface and at least a part of the primary light emission surface.

5. The vehicle light assembly according to claim 1, wherein the light receiving surface is bended around at least one, preferably at least two of the three linear independent axes.

6. The vehicle light assembly according to claim 1, wherein the light guide is arranged such that the secondary light emission surface is bended around at least two of the three linear independent axes.

7. The vehicle light assembly according to claim 6, wherein the light guide comprises at least one notch such that the primary light emission surface is discontinuous.

8. The vehicle light assembly according to claim 1, wherein the secondary light emission surface comprises a light outcoupling structure.

9. The vehicle light assembly according to claim 1, wherein the vehicle light assembly comprises at least one connector for connecting at least two end-surfaces of the at least one flexible lighting strip.

10. The vehicle light assembly according to claim 1, wherein the vehicle light assembly comprises a lighting strip terminator, wherein the lighting strip terminator is coupled to an end surface of the flexible lighting strip, wherein the light strip terminator is arranged such that light emitted by the light emitting diodes leaving the flexible lighting strip via the end surface is at least partly recycled.

11. The vehicle light assembly according to claim 1, wherein the vehicle light assembly comprises an electrical interface, wherein the electrical interface is arranged to couple the vehicle light assembly to an external power supply.

12. A vehicle light comprising a vehicle light assembly including: a flexible lighting strip comprising a multitude of light-emitting diodes, wherein the flexible lighting strip is arranged to be bended around at least two, more preferred three linear independent axes; a light guiding structure comprising a light receiving surface and a primary light emission surface, wherein the light receiving surface is arranged to receive light emitted by the flexible lighting strip, wherein the primary light emission surface is arranged to emit at least a part of the light received via the light receiving surface, and wherein the light receiving surface is arranged to define a bending of the flexible lighting strip, wherein the light guide further comprising a secondary light emission surface, and wherein the secondary light emission surface is arranged to emit at least a part of the light received via the light receiving surface, wherein the primary light emission surface is arranged to provide a higher luminance than the secondary light emission surface; a coupling structure, wherein the coupling structure is arranged to mechanically couple the flexible lighting strip to the light receiving surface in accordance with the bending defined by the light receiving surface, wherein the coupling structure is flexible, and wherein the coupling structure is a separate structure which comprises a mechanical coupling surface for receiving the flexible lighting strip and a fixing structure for fixing the coupling structure such that the flexible lighting strip is arranged between the mechanical coupling surface and the light receiving surface.

13. The vehicle light according to claim 12, wherein the vehicle light is a vehicle rear light.

14. The vehicle light according to claim 12, wherein the vehicle light is a vehicle front light.

15. The vehicle lighting assembly according to claim 1, wherein the fixing structure comprises flexible tooth configured to embrace corresponding bulges of the light guiding structure.

16. The vehicle lighting assembly according to claim 1, wherein the coupling structure comprises clamp fixing structures with a clamping base, wherein the clamping bases are connected by a hinge structure.

17. The vehicle lighting assembly according to claim 1, wherein the light guide structure comprises coupling dents.

18. The vehicle lighting assembly according to claim 1, wherein the coupling structure is made of a flexible plastic material configured to be force bended to the shape of the light guiding structure.

19. The vehicle lighting assembly according to claim 1, wherein the coupling structure is made of a material keeping shape after bending.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

(2) The invention will now be described, by way of example, based on embodiments with reference to the accompanying drawings.

(3) In the drawings:

(4) FIG. 1 shows a principal sketch of a first embodiment of a vehicle light assembly

(5) FIG. 2 shows a principal sketch of a second embodiment of the vehicle light assembly

(6) FIG. 3 shows a principal sketch of an embodiment of a separate coupling structure

(7) FIG. 4 shows a principal sketch of a first embodiment of a light guiding structure

(8) FIG. 5 shows a principal sketch of a second embodiment of a light guiding structure

(9) FIG. 6 shows a principal sketch of a third embodiment of the vehicle light assembly

(10) FIG. 7 shows a principal sketch of a fourth embodiment of the vehicle light assembly

(11) FIG. 8 shows a principal sketch of a fifth embodiment of the vehicle light assembly

(12) FIG. 9 shows a flexible lighting strip in perspective view

(13) FIG. 10 shows the lighting strip of FIG. 1 in cross section

(14) FIG. 11 shows a first set of different possible designs for the flexible layer used in the design of FIGS. 9 and 10

(15) FIG. 12 shows a second set of different possible designs for the flexible layer used in the design of FIGS. 9 and 10

(16) FIG. 13 shows a principal sketch of a cross-section a first embodiment of a connector

(17) FIG. 14 shows a principal sketch of a perspective view of the first embodiment of a connector

(18) FIG. 15 shows a principal sketch of a second embodiment of a connector

(19) FIG. 16 shows a principal sketch of a third embodiment of a connector

(20) FIG. 17 shows a principal sketch of a first embodiment of a lighting strip terminator

(21) FIG. 18 shows a principal sketch of a second embodiment of a lighting strip terminator

(22) FIG. 19 shows a principal sketch of a first embodiment of an electrical interface

(23) FIG. 20 shows a principal sketch of a second embodiment of the electrical interface

(24) FIG. 21 shows a principal sketch of a third embodiment of the electrical interface

(25) In the Figures, like numbers refer to like objects throughout. Objects in the Figs. are not necessarily drawn to scale.

DETAILED DESCRIPTION OF EMBODIMENTS

(26) Various embodiments of the invention will now be described by means of the Figures.

(27) FIG. 1 shows a principal sketch of a first embodiment of a vehicle light assembly 400. The vehicle light assembly 400 comprises a light guiding structure 200 which is in this case a light guide. The light guide comprises a slot in which the flexible light strip 100 is mounted. The flexible lighting strip 100 is fixed by means of coupling structure 300. A base of the flexible lighting strip 100 is placed on a mechanical coupling surface 302 of the coupling structure 300. Flexible tooth like fixing structures 304 of the coupling structure 300 fix the coupling structure 300 to the light guide by embracing corresponding bulges of the light guide. The flexible lighting strip 100 is arranged between the coupling structure 300 and the light guide such that the light emitted by the flexible lighting strip 100 is received by a light receiving surface 202 of the light guide.

(28) FIG. 2 shows a principal sketch of a second embodiment of the vehicle light assembly 400. The basic configuration is similar as shown in FIG. 1 discussed above. The flexible lighting strip 100 is pressed in the corresponding slot of the light guide which is bended. Flexibility of the flexible lighting strip 100 is such that the flexible lighting strip is in this case mainly bended around an axis which is normal to the light receiving surface 202 (or to the light output surface of the flexible light guide 100 as described with respect to FIG. 10). The flexible coupling structure again enables reliable fixing of the flexible lighting strip 100. The light guiding structure 200 or the light guide comprises a primary emission surface 204 at a narrow side of the light guide and a secondary emission surface 208 at the wide side of the light guide (in this embodiment perpendicular to the primary emission surface 204). The light guide comprises scattering particles which are arranged to support light extraction via the secondary emission surface 208.

(29) FIG. 3 shows a principal sketch of an embodiment of a separate coupling structure 300 similar as the coupling structures 300 shown in FIGS. 1 and 2. The coupling structure 300 comprises in this case a flexible plastic material which returns in its initial position as soon as there is no force forcing bending of the coupling structure 300. The coupling structure may be forced to bend by a curvature of a light guiding structure 200 as described with respect to FIG. 2. The coupling structure 300 may alternatively comprise a material which keeps the shape after being bended. The coupling structure 300 comprises in this embodiment clamp like fixing structures 304 with a clamping base 308. The clamping bases are connected by hinge structure 306 supporting flexibility of the coupling structure 300. A mechanical coupling surface 302 (e.g. for receiving the flexible lighting strip 100) is arranged in a channel formed by the clamps of the fixing structures 304.

(30) FIG. 4 shows a cross-section of a first embodiment of a light guide which may be used as light guiding structure 200. The light guide is shaped like a blade similar as shown in FIG. 1 with a primary emission surface 204 at a narrow side of the blade opposite to a light receiving surface 202. The light guide or light blade further comprises coupling dents 210 which are arranged to receive, for example, the clamp like fixing structure 304 as described with respect to FIG. 3 in order to fix one or more flexible lighting strip 100 between the mechanical coupling surface 302 and the light receiving surface 202. The coupling dents 210 should be made as small as possible to prevent too much light loss due to frustrated total internal reflection (TIR).

(31) FIG. 5 shows a principal sketch of a second embodiment of a light guide which may be used as light guiding structure 200. The light guide is shaped like a blade similar as discussed with respect to FIG. 4. The light guide further comprises secondary light emission surfaces 206 and 208 which are the wide sides of the light guide as discussed above with respect to FIG. 2. The secondary emission surface 206 further comprises a light outcoupling structure 206a which is a scratch in the surface of the secondary emission surface 206 supporting outcoupling of light received via the light receiving surface 202. The light guiding structure 200 further comprises a socket 203 which is arranged as coupling structure 300. The socket 203 is arranged to receive a flexible lighting strip 100 and to fix the flexible lighting strip 100. The light guiding structure 200 does therefore not need a separate coupling structure as discussed with respect to FIG. 1, 2 or 3. The bulk material of the light guide may alternatively or in addition include volume scatterers to tailor light outcoupling.

(32) FIG. 6 shows a principal sketch of a third embodiment of the vehicle light assembly 400. The vehicle light assembly 400 comprises four flexible lighting strips which are not visible in FIG. 6. A first and a second flexible lighting strip are coupled by means of the connector 500 (see discussion above and below) around a corner and emit light to a light receiving surface of a first light guiding structure. The first light guiding structure is in this case a light guide with a first primary emission surface 204A and two first secondary emission surfaces 206A, and 208A which are arranged essentially opposite to each other. The first and the second flexible lighting strip and the connector are coupled to the first light guiding structure by means of a first coupling structure 300A which extends around a corner of the first light guide. A second light guiding structure is coupled to a third flexible lighting strip by means of a second coupling structure 300B which is fixed to first coupling structure 300A by mean of a mechanical interconnect (not shown the—first and the second light guiding structure may alternatively be one light guide manufactured by molding in order to support mechanical stability of the vehicle light assembly). The second coupling structure 300B fixes the third light guiding structure to the second light guide which comprises five notches 212 separating a second primary emission surface 204B in six discontinuous parts. The sixth discontinuous parts are surfaces of a fingerlike structures extending from a base of the second light guide which is coupled by means of the second coupling structure 300B to the third flexible lighting strip. These fingerlike structures are slightly twisted with respect to each other such that the parts of the second primary emission surface 204B are arranged in a scaled or fan arrangement. The second light guide comprises second secondary emission surfaces 206B, 208B which are discontinuous in the direction of the second primary emission surface is 204B and which are connected at the base of the light guide. The first, second, third flexible lighting strip and the first and the second light guide are arranged to build a taillight with brake light functionality. The first, second and third flexible lighting strip as well as the first and the second light guide are bended in all three dimensions such that the first and the second primary emission surfaces 204A, 204B as well as the first and the second secondary emission surface is 206A, 206B, 208A, 208B are visible for a driver of a car behind a car comprising the vehicle light assembly 400. The taillight essentially encloses a flashing light which comprises a fourth flexible lighting strip (not shown), a third coupling structure (not shown) and a light guiding structure which is a light guide with a third primary emission surface 204C and secondary emission surfaces 206C, 208C enclosing an angle of more than 90° with the third primary emission surface 204C. The light guides are arranged such that luminance of the primary emission surfaces 204A, 204B, 204C is higher than luminance of the secondary emission surfaces 206A, 206B, 246C, 208A, 208B, 208C. Especially the secondary emission surfaces 206A, 206B, 208A, 208B of the taillight provide a haze like appearance. The vehicle lighting assembly 400 may further comprise mechanical support structures in order to provide a reliable stability of the vehicle light assembly 400. The mechanical support structures may be integrated parts of the light guides. The combination of the flexible lighting strips, coupling structures and light guiding structures enables complex vehicle lighting assemblies.

(33) FIG. 7 shows a principal sketch of a cross-section of a fourth embodiment of the vehicle light assembly 400. The light guiding structure 200 comprises in this case a reflective structure with a light receiving surface 202 which is at the same time diffusely reflective in order to reflect light received from a flexible lighting strip 100. The light receiving surface 202 coincides in this case at least partly with primary emission surface 204. The flexible lighting strip 100 is mechanically coupled to the light guiding structure 200 by means of a coupling structure 300 which comprises a slot with a mechanical coupling surface 302 and a fixing structure 304. The shape of the slot and the shape of the mechanical coupling surface 302 defines the shape and especially bending of the flexible lighting strip 100 which is not visible in the two-dimensional drawing. The fixing structure 304 fixes the flexible lighting strip 100 in the slot such that the shape of the flexible lighting strip 100 defines together with the illumination characteristic of the flexible lighting strip 100 illumination of the light receiving surface 202. The reflective surface may optionally comprise one or more areas which are not reflective. Light received at not reflective areas of the light receiving surface 202 may enter transparent carrier material which may be used to build the light guiding structure 200. Light entering the transparent carrier material may leave the transparent carrier material at defined surface sections (primary or secondary emission surfaces which are not shown) of the light guiding structure 200. The light guiding structure 200 may in this case be a combination of a reflective structure and a light guide.

(34) FIG. 8 shows a principal sketch of a cross-section of a fifth embodiment of the vehicle light assembly 400. The light guiding structure 200 comprises in this case a scattering structure with a scattering element at the primary emission surface 204. The light guiding structure 200 comprises a transparent material such that the light received via a light receiving surface 202 can reach the scattering element. A flexible lighting strip 100 is mechanically coupled to the light guiding structure 200 by means of a coupling structure 300 which comprises a slot with a mechanical coupling surface 302 and a fixing structure 304. The shape of the slot and the shape of the mechanical coupling surface 302 define shape and especially bending of the flexible lighting strip 100 which is not visible in the two-dimensional drawing. A light emitting surface of the flexible lighting strip 100 is in this embodiment in contact with the mechanical coupling surface 302. The mechanical coupling surface 302 thus comprises the light receiving surface 202 of the light guiding structure 200. The fixing structure 304 fixes the flexible lighting strip 100 in the slot such that the shape of the flexible lighting strip 100 defines together with the illumination characteristic of the flexible lighting strip 100 illumination of the light receiving surface 202 and the scattering element at the primary emission surface 204. It is thus not necessary that the light receiving surface 202 touches the flexible lighting strip 100. There may, for example, be an air gap between the light receiving surface 202 and the light emitting surface of the flexible lighting strip 100. Fixing structure 304 and mechanical coupling structure 302 may, for example, in such a case be the same.

(35) FIGS. 9, 10, 11 and 12 show a flexible elongate lighting strip having at least one line of LEDs mounted on a flexible support and carried by a carrier structure 14. The carrier structure 14 provides light mixing within a channel over the line of LEDs and a flexible layer is provided in the channel for further light processing.

(36) FIG. 9 shows a flexible lighting strip 100. A line of LEDs 10 is mounted on an elongate, flexible support 12. The flexible support 12 is supported by the carrier structure 14 having a flexible base 16 on which the flexible support 12 is mounted and flexible side walls 18 to each side of the flexible support 12, defining a channel 20 over the base 16.

(37) The channel may have parallel sides as shown, by they may instead taper, with a wider top opening than the base. This forms a funnel shape.

(38) The base and side walls are preferably part of a single integrated component, which itself may be extrusion molded. It may be molded around the support 12, or else the carrier structure 14 may be fitted around the support 12 after manufacture. Alternatively, the carrier structure 14 may comprise separate side walls and base which are assembled together.

(39) The flexible support 12 provides the electrical connections to the LEDs 10 and also provides heat removal.

(40) The LEDs 10 emit light into the channel 20, and in some examples the surfaces of the side walls 18 provide light mixing so that a more uniform strip of illumination is defined. The height of the channel together with the reflection characteristics of the side walls define a beam shaping function, whereby the light output intensity is greater in the normal direction (perpendicular to the support 12).

(41) A flexible layer 22 is provided in the channel. This layer performs an additional light processing function. This function is to make the light output more uniform, so that the spot-like appearance of the LEDs is made less visible, and/or to increase the collimation and thereby provide directional control.

(42) All of the components (apart from the LEDs themselves) are flexible so that the complete strip may be deformed into almost any desired 3D configuration. It may be bent into an arc on a flat plane (parallel to the support 12) or it may be deformed into an arc out of plane. The lighting strip may be mass produced as a small range of designs (for example of different dimensions and materials), and each design may then be suitable for a large range of end applications.

(43) The top of the channel, which may be defined by the top of the flexible layer 22, defines the light output surface, which is in a strip shape.

(44) The optical function of the layer 22 may be implemented by a scattering arrangement. The scattering may be uniform along the strip or there may be different scattering intensities at different points in the volume of the layer, for example by having a variation in the volume density of scattering particles. The different scattering intensities may vary periodically to match the spacing between the LEDs. The scattering intensity may also vary in the normal direction. The flexible layer thus may be used to provide shaping of the light output from the LEDs and homogenization of the light.

(45) The flexible layer also provides protection to the electrical tracks carried by the flexible support 12.

(46) The scattering function may be used to generate a specific desired beam. Many beam variations are possible by suitable selection of the layer 22, even for a design which remains identical in all other respects. In this way, only one component is varied to achieve a wide range of possible designs. A number of specific examples of design for the flexible layer are presented below.

(47) FIG. 10 shows a cross section perpendicular the length direction. It shows that the LED comprises an LED chip 24 and an optional output structure 26. The LED chip 24 may be a direct color emitting chip (i.e. the output of the chip is a desired color to be emitted from the lighting strip). Alternatively, the LED chip may emit one color and a phosphor converter may be provided for changing the output color. For example, the LED may be a blue chip, and a yellow emitting phosphor is used to create a white light output.

(48) This phosphor converter may be part of the chip which is mounted on the flexible support 12, or it may be defined by the output structure 26.

(49) The output structure may instead or additionally provide a beam shaping function, and be formed as a refractive lens.

(50) In all cases, the output structure 26 provides protection to the chips.

(51) By way of example, the overall product (the outer dimensions of the carrier structure 14) may be a width 8 mm and a height 5 mm. The channel may then have dimensions of 3 mm×3 mm.

(52) In general, the lighting strip may have a width less than 20 mm, more preferably less than 10 mm, and a height less than 12 mm more preferably less than 8 mm. The strip can have any length, for example tens of centimeters.

(53) There may typically be tens to hundreds of LEDs along the line. They may for example be spaced with a pitch of between 2 mm and 50 mm, for example between 2 mm and 30 mm, for example between 5 mm and 20 mm.

(54) Some examples of the materials and designs that may be used to form the different components will now be discussed.

(55) The flexible support 12 may comprise a flexible printed circuit board or a flexible electrical connection structure (e.g. lead frame). A flexible printed circuit board may for example be made of polyimide with copper tracks, although many other flexible carrier materials may be used. A flexible electrical connection structure may be formed of a sheet metal, such as Cu, Al, Zn, Fe or alloys.

(56) In either case, the support carries the LEDs and electrical tracks and is able to be deformed to adopt a desired shape. The flexible support 12 may be carried directly over the base 16 of the carrier structure 14, or there may be additional layers of material, for example for heat spreading.

(57) As mentioned above, the LED may include a wavelength converting layer. This may be formed as part of the LED itself so that the discrete LED to be mounted on the flexible support 12 incorporates a phosphor layer. It may instead be a separate component mounted over the LED, for example a rigid plastic capsule which contains the phosphor converter. The LED package may also include electronic components such as basic components like resistors, or more complicated components such as sensors or integrated circuits,

(58) The output structure 26 may comprise a silicone glob, or a molded part formed from rigid plastic. It may instead by formed by a dam and fill process. The output structure may comprise the phosphor as explained above, or it may be translucent (and just serve as a protection layer), or it may provide an optical beam shaping function.

(59) The carrier structure 14 may be formed from a flexible white material or a white-coated material or a mirror-coated material, so that the side walls mix the light within the channel by scattering of light at the channel sides. In this way, a continuous strip of illumination may be formed. However, discrete light output points may instead be visible if desired. The carrier structure 14 may be formed from extruded silicone, although other bendable materials are also possible. The carrier structure 14 may also be selected as a thermally conductive material to provide a heat dissipation function.

(60) Note that in some examples light may not reach the side walls because of total internal reflection at the sides of the flexible layer which is within the channel. For example, there may be an air gap between the sides of the flexible layer, and total internal reflection may then take place at the layer-air interface. In this case, the carrier 14 does not need reflecting side walls.

(61) The flexible layer 22 may comprise an extruded component such as silicone. In this case, it may be fitted mechanically into the channel. It may instead be formed in the channel, for example as a liquid which is then cured in place.

(62) An upper surface of the flexible layer 22 defines the light output surface of the flexible lighting strip 100. A (local) normal 21 to the light output surface defines a primary direction of light emission of the flexible lighting strip 100. The normal 21 is essentially parallel at every point of the light output surface as long as the flexible lighting strip 100 is not bended. The flexible lighting strip 100 can especially be bended around the normal 21. Bending around the different axes may be limited by the geometry of the flexible lighting strip 100, the width and height of the flexible lighting strip 100 or the material properties of the different elements of the flexible lighting strip 100.

(63) FIG. 11 shows three examples of possible design for the flexible layer.

(64) FIG. 11(a) shows the first design in cross section across the channel and FIG. 11(b) shows the first design in cross section along the channel.

(65) The output structure comprises a transparent glob. There is a coating 30 on the glob, for example a white paint pattern. The layer 22 is a filling which fills the channel. It has scattering particles dispersed throughout. These may for example be applied as a dye. The top of the filling is covered with an exit film 32 with linear prisms or a Fresnel structure.

(66) The white pattern on top of the transparent glob makes the light more uniform within the channel in a first step. The glob functions as a larger secondary light source than the chip itself.

(67) FIG. 11(c) shows the second design in cross section across the channel and FIG. 11(d) shows the second design in cross section along the channel.

(68) The output structure 26 again comprises a transparent glob. The layer 22 again has the structure of a filling with scattering particles dispersed throughout. The top of the filling is covered with an exit film 32 with linear prisms or a Fresnel structure. This second design is thus the same as the first but without the coating on the protective glob.

(69) FIG. 11(e) shows the third design in cross section across the channel and FIG. 11(f) shows the third design in cross section along the channel.

(70) The output structure 26 again comprises a transparent glob. The layer 22 comprises an optical processing film 34 with partial transmittance, for example a reflector film with a hole array. An exit film 36 comprises a lens array.

(71) FIG. 12 shows four further examples of possible design for the flexible layer.

(72) FIG. 12(a) shows the fourth design in cross section across the channel and FIG. 12(b) shows the fourth design in cross section along the channel.

(73) The output structure 26 again comprises a transparent glob. The layer 22 is shaped structure which does not fill the channel in the sideways direction. Instead, air gaps 40 are present at the sides and beneath. The cross section varies along the length so that a beam shaping function is dependent on the position along the length of the channel. This enables a more uniform light output to be created along the length of the channel. In particular, total internal reflections are used to pass light along the layer 22 in the manner of a light guide, with the light escaping at locations along the top of the channel which are remote from the light sources themselves.

(74) FIG. 12(c) shows the fifth design in cross section across the channel and FIG. 12(d) shows the fifth design in cross section along the channel.

(75) The output structure 26 again comprises a transparent glob, but rather than having the form of a single lens shape, it has a double lens shape along the length axis of the channel. This serves to make the light output more uniform in the length direction. The layer 22 comprises a prismatic or Fresnel film 42, and there is a further prismatic or Fresnel exit film 44. These films combine to implement a collimation function.

(76) The flexible layer may thus comprise a multi-layer structure. In the example of FIGS. 12(c) and 12(d), the multiple layers may be the same material but with different surface structures. They may instead be formed from different materials, or they may be formed as layer (of the same or different materials) with different optical coatings.

(77) FIG. 12(e) shows the sixth design in cross section across the channel. It is extruded along the channel so no cross section along the channel is shown.

(78) The output structure 26 again comprises a transparent glob. The layer 22 is shaped structure which does not fill the channel in the sideways direction. Instead, air gaps 46 are present at the sides and beneath. The cross section is constant along the length. Total internal reflections are used to shape the light, for example at the top of the channel a lens shape 48 is defined.

(79) FIG. 12(f) shows the seventh design in cross section across the channel. It is extruded along the channel so no cross section along the channel is shown.

(80) The output structure directs the light in a sideways direction. The design includes a so-called dark hole optic, in which the output structure has a high reflective coating on top, shaped to reflect light to the sides, leaving a central dark hole. The lateral light is reflected by the side walls 50 of the channel, which in this example are curved rather than straight. These side walls thus perform a light shaping function. There is a prismatic or Fresnel exit film 52.

(81) It will be seen from the examples above that the layer may be clear or diffusive, and it may be formed as a multi-layer structure. It may have scattering elements and/or it may have diffractive elements. In the case of a multi-layer structure, the multiple layers may be formed from different materials or materials with different optical coatings. There may be refractive, diffusive, diffractive or reflective optical elements incorporated into the layer. Optical films may also be incorporated into the layer. Alternatively, the main volume of the channel may be empty, and the layer comprises only a top exit layer or a layer within the channel.

(82) The overall design is created to generate desired characteristics of the light emitted from the strip. This light may be collimated or diffuse, uniform or shaped into discrete output regions.

(83) The example above shows one line of LEDs along the strip. There may however by multiple lines of LEDs. Electrical connection to the LEDs may be made from one or both ends of the strip, or from the back, through an opening in the base 16. The electrical connection to the lighting strip has not been shown as any conventional PCB or lead frame connector may be used.

(84) The LED driver electronics may be external to the lighting strip or it may be integrated within the lighting strip.

(85) FIG. 13 shows a principal sketch of a cross section of a first embodiment of a connector 500. The cross section shows a carrier structure with a flexible base 16 and flexible side walls 18 building a channel as discussed with respect to the flexible lighting strip shown in FIG. 10. The channel is filled with a flexible layer 22 in order to distribute light received from flexible lighting strips via a coupling interface (not shown). The received light is emitted via a light output surface of the flexible layer 22 with a main emission direction along a local normal of the light output surface 21. The connector 500 may optionally comprise a carrier structure with, for example, a flexible electrical connection structure (not shown) in order to enable electrical connection of two or more flexible lighting strips optically and mechanically coupled by means of the connector.

(86) FIG. 14 shows a principal sketch of a perspective view of the first embodiment of a connector 500. The connector 500 is arranged to connect two identical flexible lighting strips 100 in a linear arrangement by means of two coupling interfaces 502. Length, reflectivity and scattering properties of the base, the side walls and the layer within the channel defined by the base and the side walls are arranged such that luminance of a light emission surface of the connector 500 is essentially the same than luminance of the coupled flexible lighting strips 100. The material of the base and side walls may be flexible or rigid depending on the intended arrangement of the vehicle light assembly. A flexible material may enable to bend the two flexible lighting strips 100 optically and mechanically coupled by means of the connector 500 across the connector 500.

(87) FIG. 15 shows a principal sketch of a perspective view of a second embodiment of a connector 500. The general configuration of the connector 500 is the same as discussed with respect to FIG. 13. A rigid base 16A and two rigid sidewalls 18A form a channel with a rectangular corner. The channel may be formed by means of a aluminum profile. The channel is filled with a transparent rigid layer 22A which comprises two coupling interfaces 502. The material of the transparent rigid layer 22A may, for example, be a transparent plastic. The connector 500 enables a connection of two flexible lighting strips 100 at an angle of 90° by coupling the flexible lighting strips 100 to the coupling interfaces 502. Other configurations of such edge connector may enable a connection at different angles than 90° (e.g. at an acute angle or obtuse angle). Reflectivity of the rigid base 16A and the rigid side walls 18A in combination with a defined scattering within the rigid layer 22A and the length of the arms of the edge connector are preferably arranged that a homogeneous luminance of the combination of the flexible lighting strips and the edge connector is enabled. The edge connector may alternatively comprise flexible materials as discussed with respect to FIG. 13.

(88) FIG. 16 shows a principal sketch of a third embodiment of a connector 500 which is arranged to connect three flexible lighting strips 100 by means of corresponding coupling interfaces 502. The general configuration of the connector 500 is similar as described with respect to FIG. 13. The base and side walls and optionally the transparent material placed in the channel formed by the base and side walls are in this case made of a rigid material such that the Y shape form of the connector 500 is fixed. Length of the three arms of the connector is adapted such that light outcoupling via a light output surface of the connector is such that luminance of the light output surface of the flexible lighting strips 100 and the connector 500 is essentially the same. Alternatively, length and outcoupling of light entering connector 500 may be arranged to provide, for example, a smooth transition between flexible lighting strips with different luminance. Furthermore, connector 500 may be arranged to provide a defined lighting effect (e.g. highest luminance at the crossing of the branches or arms of connector 500).

(89) FIG. 17 shows a principal sketch of a cross section an embodiment of a lighting strip terminator 700. The lighting strip terminator comprises a coupling interface 702 in order to receive light (indicated by the arrows) from a flexible lighting strip 100. The lighting strip terminator 700 comprises a base, side walls and a layer for distributing the light between the side walls similar as discussed with respect to the connector 500 or the flexible lighting strip 100 above. The difference is that in this embodiment there is a wedge arranged in the channel between the side walls such that light received from the flexible lighting strip 100 is reflected in the direction of a light output surface of the lighting strip terminator 700 which is built by a surface of the layer as discussed above. The preferably diffuse reflection by means of the base and the side walls is arranged such that luminance of the light output surface of the lighting strip terminator 700 is homogeneous and essentially the same as luminance of the flexible lighting strip 100 coupled to the lighting strip terminator 700. Scattering particles may optionally be added to the material of the layer in order to provide a defined luminance of the light output surface of the lighting strip terminator 700. The tapered shape of the base can also be more rounded, e.g. parabolic or another optimized shape in order to direct the light more forwards out of the light output area of the lighting strip terminator 700. Essential here is that the light can run until the end of the light strip terminator.

(90) FIG. 18 shows a principal sketch of a second embodiment of a lighting strip terminator 700. The lighting strip terminator 700 is in this embodiment made of a piece of hard plastic or aluminum. It has a flat surface (coupling interface) that faces an end face (coupling interface) of a flexible lighting strip 100. This flat surface comprises a reflector 704 which is highly specularly reflective reflecting the light back into the flexible lighting strip 100. In this way light that would otherwise be lost/absorbed is injected back into the light guide of the flexible lighting strip 100 and has a second chance of being emitted from the light output surface. The highly reflective face of the lighting strip terminator 700 is typically made of highly polished aluminum or coated silver foils. Also special highly reflective foils like Alanod may be used. The distance between the end face of the flexible lighting strip 100 and the middle of the next LED is preferably half of the distance between two LEDs of the flexible lighting strip 100 such that the specular reflective reflector 704 has the same effect as a further LED at the opposite side of the reflector 704 (virtually within the lighting strip terminator 700).

(91) FIG. 19 shows a principal sketch of a cross-section of a first embodiment of an electrical interface 800. The cross section shows a cross-section of the flexible lighting strip as discussed with respect to FIG. 10 with a flexible base 16 flexible side walls 18 and a flexible layer deposited in the channel formed by the base 16 and flexible side walls 18 as discussed above. An LED chip 24 is electrically connected by means of the flexible support 12 comprising the flexible electrical connection structure. Electrical connection pins 802 are arranged to electrically connect the conducting paths of the flexible electrical connection structure. A body of the electrical interface 810 surrounds the electrical connection pins 802 such that in this embodiment a female plug is formed. The female plug can be connected by means of a corresponding male plug such that electrical power can be provided by means of a wire connected to the female plug. The other end of the wire can be provided with any suitable plug or electrical connection technology which may be beneficial in the corresponding application in a rear light or front light.

(92) FIG. 20 shows a principal sketch of a second embodiment of the electrical interface 800. The general configuration is essentially the same as discussed with respect to FIG. 19. The electrical interface 800 is arranged at one of the longitudinal end surfaces of a flexible lighting strip. Such an electrical interface 800 may be used if one end of a flexible lighting strip is essentially invisible in a vehicle light assembly.

(93) FIG. 21 shows a principal sketch of a third embodiment of the electrical interface 800. The general configuration is essentially the same as discussed with respect to FIG. 19. The electrical interface 800 is arranged at an intermediate position of a flexible lighting strip. Such an electrical interface 800 may be used if both ends of a flexible lighting strip are visible in a vehicle light assembly. The flexible lighting strip may, for example, be coupled by means of two passive connectors without electrically conductive cables in the base to two flexible lighting strips with electrical interfaces 800 as described in FIG. 20.

(94) While the invention has been illustrated and described in detail in the drawings and the foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive.

(95) From reading the present disclosure, other modifications will be apparent to persons skilled in the art. Such modifications may involve other features which are already known in the art and which may be used instead of or in addition to features already described herein.

(96) Variations to the disclosed embodiments can be understood and effected by those skilled in the art, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality of elements or steps. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

(97) Any reference signs in the claims should not be construed as limiting the scope thereof.

LIST OF REFERENCE NUMERALS

(98) 10 light-emitting diode (LED) 12 flexible support 14 carrier structure 16 flexible base 16A rigid base 18, 50 flexible side walls 18A rigid side walls 20 channel 21 normal of light output surface 22 flexible layer 22A rigid layer 24 LED chip 26 output structure 30 coating 32 exit film 34 optical processing film 36 array of lenses of facets 40, 46 air gap 42, 44 prismatic or Fresnel exit film 48 lens shape 100 flexible lighting strip 200 light guiding structure 202 light receiving surface 204 primary emission surface 204A first primary emission surface 204B second primary emission surface 204C third primary emission surface 206A, 208A first secondary emission surfaces 206B, 208B second secondary emission surface 206C, 208C third secondary emission surface 206, 208 secondary emission surface 206a light outcoupling structure 210 coupling dent 212 notch 300 coupling structure 300A first coupling structure 300B second coupling structure 302 mechanical coupling surface 304 fixing structure 306 hinge structure 308 clamping base 400 vehicle light assembly 500 connector 502, 702 coupling interface 700 lighting strip terminator 710 reflective wedge 722 (flexible) base 800 electrical interface 802 electrical connection pin 810 body of electrical interface