WO2021004806A1

WO2021004806A1 - Illumination device for vehicles

Info

Publication number: WO2021004806A1
Application number: PCT/EP2020/067894
Authority: WO
Inventors: Bernd Fischer; Carsten Hohmann; Werner Kösters; Martin Mügge; Thomas Rettweiler; Christian Smarslik; Benjamin Willeke
Original assignee: HELLA GmbH & Co. KGaA
Priority date: 2019-07-09
Filing date: 2020-06-25
Publication date: 2021-01-14
Also published as: DE102019118511A1

Abstract

The invention relates to an illumination device for vehicles, comprising a light guide (1, 21, 22, 26) and a light source (2) arranged on an end side (3) thereof, wherein diffuser elements (7, 11) are arranged in a distributed manner in the light guide (1, 21, 22, 26) for deflecting the light (4) coupled into the light guide (1, 21, 22, 26) in the direction of a casing surface of the light guide (1, 21, 22, 26), and wherein colour change elements (9, 13) are arranged in a region of the casing surface of the light guide (1, 21, 22, 26), by means of which the coupled-in light (4) can be converted from a first wavelength into a second wavelength, wherein the light guide (1, 21, 22, 26) is flexibly designed, the light guide (1, 21, 21, 26) has first colour change elements (9) in a first longitudinal section (5) thereof for converting the coupled-in light (4) of the first wavelength into light (10) of the second wavelength in order to generate a first signal light function, and the light guide (1, 21) has second colour change elements (9) in a second longitudinal section (6) thereof for converting the coupled-in light (4) of the first wavelength into light (14) of a third wavelength, which differs from the light (10) of the second wavelength, in order to generate a second signal light function.

Description

Lighting device for vehicles

The invention relates to a lighting device for vehicles with a light guide and a light source arranged on one end face of the same, wherein diffuser elements are arranged distributed in the light guide for deflecting the light coupled into the light guide in the direction of a lateral surface of the light guide and in a region of the lateral surface of the Light guide color change elements are arranged, by means of which the coupled light can be converted from a first wavelength to a second wavelength.

From DE 10 2014 103 737 A1 a lighting device for vehicles is known which comprises a light guide and a light source arranged on one end of the same. The light guide has only a transparent material without light-scattering elements in a first longitudinal section and light-scattering elements in a second longitudinal section. When switched off, the light guide has a homogeneous appearance, while when the light source is switched on, light is emitted only in the second longitudinal section in accordance with a given emission characteristic to generate a signal light function. The disadvantage of the known lighting device is that it only serves to generate a single signal function.

From DE 10 2018 004 285 A1 a lighting device for vehicles with a light guide and a light source arranged at the end of the same is known, the light guide on the one hand having diffuser elements for deflecting the light coupled into the Lichtlei ter in the direction of a lateral surface of the light guide and on the other hand having color changing elements , by means of which the coupled light can be converted into light of a different wavelength. A desired signal color can be generated by means of the color change elements, so that the light guide is used to generate a predetermined signal light function. The disadvantage of the known lighting device is that when the lighting device is switched on, only a single signal light function is generated. The object of the present invention is to develop a lighting device for vehicles with a light guide and a single light source in such a way that the light guide has a homogeneous appearance when the lighting device is switched off and at least two different signal lights when the lighting device is switched on functions generated.

To solve this problem, the invention in connection with the preamble of claim 1 is characterized in that the light guide is flexible, that the light guide has first color changing elements in a first longitudinal section of the same for converting the coupled light of the first wavelength into light of the second Wavelength for generating a first signal light function and that the light guide has second color-changing elements in a second longitudinal section of the same to convert the coupled light of the first wavelength into light of a third wavelength that differs from light of the second wavelength to generate a second signal light function.

The particular advantage of the invention is that light bundles for generating different signal functions can be emitted in the direction of extent by means of locally differently arranged color change elements. Because the different longitudinal sections have lateral surfaces that point in different directions, at least two signal light functions can be generated simultaneously and preferably in different main emission directions.

According to a preferred embodiment of the invention, diffuser elements are arranged in a directed manner within the light guide such that light striking them is deflected at a radial scattering angle range of 60 ° to 80 °. In this way, a relatively large illuminated area can advantageously be created, preferably in a vertical plane, in order to meet the requirements of the signal light function. According to a further development of the invention, the diffuser elements are arranged in the light guide in such a way that the coupled light is deflected at the same under an axial scattering angle range of at least 100 °. When the light guide is arranged horizontally, the axial scattering angle range thus runs in a horizontal plane. A relatively homogeneous illuminated graphic can advantageously be generated in this way.

According to a preferred embodiment of the invention, the first and the second longitudinal section of the light guide run in a straight line and / or arcuate. In the two different longitudinal sections, the light is deflected in different main emission directions or emitted from the respective longitudinal section. A daytime running light and a side marker light, for example, can thus advantageously be generated by means of a single light guide and a single light source, the main emission directions of the longitudinal sections running essentially perpendicular to one another.

According to a development of the invention, the second longitudinal section directly adjoins the first longitudinal section of the light guide. The entire length of the light guide can advantageously be used for different signal light functions here. Alternatively, an intermediate section of the light guide can be provided between the first longitudinal section and the second longitudinal section, which has no diffusor elements. In the intermediate section there is therefore no light emission to the outside. Instead, the light is only passed on to the second longitudinal section through total reflection on the lateral surfaces of the intermediate section. In this way, two signal light functions that are spatially delimited from one another can advantageously be generated.

According to a development of the invention, the diffuser elements are dimensioned in a micrometer range. The diffuser elements are preferably flat or slightly curved. The light beam impinging on the diffuser element at an angle of incidence is reflected at an angle of reflection which essentially corresponds to the angle of incidence. The diffuser elements are preferably evenly distributed in the first and second longitudinal sections arranged so that a homogeneous light deflection can take place in the direction of the lateral surface. The number of diffuser elements per unit volume depends on the length of the light guide and the light intensity of the light source. The longer the light guide, the smaller the density distribution of the diffuser elements in the light guide.

According to a further development of the invention, the light guide has a reflector element on a side opposite the light coupling-out side, by means of which light striking the same is reflected in the direction of the light coupling-out side. The degree of decoupling of the light can be influenced by dimensioning and distributing the reflector elements along a longitudinal side of the light guide. If, for example, the reflective element in the first longitudinal section of the light guide is larger per area than in the second longitudinal section, the contribution of the reflective element to the coupling out of light in the first longitudinal section is greater than in the second longitudinal section.

According to a development of the invention, the reflection element and / or the color change element are each designed as a coating that is applied to the jacket side of the light guide. The reflector element and the color change element are arranged on mutually opposite sides of the light guide.

According to a development of the invention, the second longitudinal section of the Lichtlei age is formed by a plurality of light guide segments which are arranged in the direction of extent of the light guide alternating with light guide segments of the first longitudinal section. In this way, an uninterrupted white light signature can advantageously be generated if the number of diffuser elements in the light guide segments of the second longitudinal section is smaller than in the light guide segments of the first longitudinal section and / or the dimensions of the reflector elements in the light guide segments of the second longitudinal section are smaller than in the light guide segments of the first longitudinal section. It is assumed here that a continuous section of the first longitudinal section adjoins the second longitudinal section. closes. Only in the area of the second longitudinal section is the first longitudinal section broken or segmented.

According to a further development of the invention, the light guide has a loop section with ends tapering towards one another, to which the light guide is connected in accordance with a predetermined shape. The loop section can be used at least in part to form the second longitudinal section of the light guide, while the first longitudinal section, beginning with the ends of the loop section, is used for another signal light function. The other signal light function, which is generated by the first longitudinal section, is given a continuous or uninterrupted appearance due to the spatial proximity of the loop section ends, which can be used, for example, for daytime running lights.

Exemplary embodiments of the invention are explained in more detail below with reference to the drawings.

Show it:

Fig. 1 is a schematic front view of a headlight with an arc-shaped light guide for generating a daytime running light and Seitenmarkie approximate light function,

FIG. 2 shows a schematic plan view of the light guide according to FIG. 1 according to a first embodiment,

3 shows a schematic top view of the light guide according to FIG. 1 according to a second embodiment,

4 is a schematic front view of the headlight with a light guide following the outer contour of the headlight for generating two signal light functions according to a third embodiment, 5 is a schematic front view of the headlight with a light guide following the outer contour of the headlight for generating two signal light functions according to a fourth embodiment,

6 is a schematic front view of the headlight with a light guide following the outer contour of the headlight for generating two signal light functions according to a fifth embodiment,

7 is a schematic front view of the headlight with a light guide following the outer contour of the headlight for generating two signal light functions according to a sixth embodiment and

8 is a schematic front view of the headlight with a light guide following the outer contour of the headlight for generating two signal light functions according to a seventh embodiment.

A lighting device for vehicles can be used as a headlight or rear light, whereby it is preferably used to generate a position light or daytime running light and side marker light. If necessary, the lighting device can also generate more than two different signal light functions.

According to one embodiment of the invention according to FIG. 1, the lighting device has an elongated light guide 1 which is arranged following a lower contour 19 and a lateral contour 20 of the headlight housing. The lateral area of the light guide 1 extends at an edge of the headlight, which serves as the end of an upright side wall of the vehicle, on whose doors are arranged. The lateral area is thus arranged on a side of the headlight housing facing away from the vehicle center axis. A light source 2 is arranged in the area of an end face 3 of the light guide 1 facing the vehicle center axis. In the present exemplary embodiment, the light guide 1 is coupled in only from a single end face 3. If necessary, light can also be coupled in from an opposite end face 3 '. As a light source 2, an LED light source or laser light source is used which, for example, couples in blue light 4.

The light guide 1 is linear and / or rod-shaped. The light guide 1 be made of a flexible fiberglass material. The light guide 1 can be circular or ellipsoidal or polygonal in cross section.

According to a first embodiment of the light guide 1 according to FIG. 2, it consists only of a first longitudinal section 5 and a second longitudinal section 6. The first longitudinal section 5 extends essentially along the lower outer contour 19 of the headlight. The first longitudinal section 5 is used to generate a first signal light function, namely a daytime running light function. The second longitudinal section 6 extends essentially in the vertical direction in the side area of the headlight facing away from the vehicle center axis and serves to generate a side marker light function.

The second longitudinal section 6 directly adjoins the first longitudinal section 5. The light 4 is only coupled into the first longitudinal section 4. Diffuser elements 7 are distributed in the first longitudinal section 5 in such a way that the coupled-in light 4 is deflected in the main emission direction H1 of the first signal light function (daytime driving light function). A light outcoupling lateral surface 8 of the first longitudinal section 5 has first color change elements 9, by means of which the coupled light 4, which has a first wavelength, is converted into light 10 of a second wavelength. The converted and decoupled light 10 has a white light color and can thus be used for the daytime running light function. The main beam direction H1 of the daytime running lights coincides with a direction of travel F of the vehicle.

In the second longitudinal section 6, diffuser elements 11 are arranged in such a way that the coupled-in light 4 is deflected in the direction of a main emission direction H2 of the Seitenmarking light function. The main emission direction H2 of the side marker light function runs perpendicular to the direction of travel F. The diffuser elements 11 deflect the light 4 in the direction of a light-decoupling lateral surface 12 of the second longitudinal section 6, which is provided with a second color-changing element 13. The second color change element 13 is designed in such a way that the coupled-in light 4 of the first wavelength is converted into light 14 of a third wavelength.

In the present exemplary embodiment, the coupled-out light 14 has a yellow color.

Both the diffuser elements 7 of the first longitudinal section 5 and the diffuser elements 11 of the second longitudinal section 6 are preferably designed such that they deflect the coupled-in light 4 by 90 °. The diffuser elements 7, 11 are preferably aligned such that they are arranged at an angle of 45 ° with a central axis M of the light guide 1 or, depending on the curvature of the light guide 1, in an angular range of 30 ° to 60 ° to the central axis M. It is assumed that the angle of incidence α is equal to the angle of reflection β of the light 4 on the diffuser element 7, 11. The diffuser element is, for example, rod-shaped and has a length in the range of pm, for example 5 pm to 50 pm . The diffuser elements 7, 11 arranged in the light guide material can be brought into the desired alignment with the central axis M of the light guide 1 by external excitation. The distribution of the diffuser elements 7, 11 is such that higher light intensities are emitted from the first longitudinal section 5 than from the second longitudinal section 6. The distribution density of the diffuser elements 7 in relation to a volume area is thus greater in the first longitudinal section 5 than in the second longitudinal section 6. The light is deflected on the outer surface of the light guide that is coupled out (first longitudinal section 5, second longitudinal section 6) under a radial scattering angle range Y of 60 ° to 80 °. The radial scattering angle range extends in a plane perpendicular to the central axis M of the light guide 1. Furthermore, the light is extracted at an axial scattering angle range g of at least 100 °. The axial scattering angle range extends in one along which the central axis M runs.

According to a further embodiment of the invention according to Figure 3, the Lichtlei ter 1 has the same shape as according to the embodiment of Figure 2. A lower The only difference is that the second longitudinal section 6 is arranged at a distance from the first longitudinal section 5. Between the first longitudinal section 5 and the second longitudinal section 6 there extends an intermediate section 15 of the light guide 1, in which no diffuser elements are arranged and thus no specific light emission from the outer surface of the light guide 1 takes place. In this respect, the inter mediate section 15 does not need to be provided with color change elements. If necessary, the intermediate section 15 can also be covered with a panel (not shown). It is essential that the light emission for the side marker light and the daytime running light are clearly spatially separated. For an external observer, the result is an appearance of two separately arranged signal light functions. However, these two signal light functions can actually be generated by means of a single light source 1.

The same components or component functions of the exemplary embodiments are provided with the same reference numerals.

According to a further embodiment of the invention according to FIG. 4, a light guide 21 following the outer contour of the headlight is provided, which - as in the previous embodiments - serves to generate two different signal light functions. One difference is that the first longitudinal section 5 is interrupted by the second longitudinal section 6. The first longitudinal section 5 thus adjoins both ends of the second longitudinal section 6. In contrast to the previous embodiments of the invention, the Lichtlei ter 21 has a reflector element 18 on a side opposite to the outer surface to be coupled out. The light 4 hitting the reflector element 18 is reflected in the direction of the light-decoupling lateral surface, so that in cooperation with the diffuser elements 7, 11, the degree of decoupling is increased. The Reflekto element 18 and the color changing elements 9, 13 can for example be formed as Beschich lines.

According to a further embodiment of the invention according to FIG. 5, in contrast to the embodiment according to FIG. 4, the second longitudinal section 6 is not continuous formed from a first end to a second end of the same, but formed seg mented. The second longitudinal section 6 has a plurality of light guide segments 16, which are arranged in the longitudinal direction or extension direction E of the light guide 21 alternating with light guide segments 17 of the first longitudinal section 5. The length of the light guide segments 16 in the direction of extent E of the light guide 21 is preferably smaller than that of the light guide segments 17 of the first longitudinal section 5. For the viewer, this creates the impression of an uninterrupted white light signature of the first light section 5 from a short distance the light guide segments 16 of the second longitudinal section 6 have the same design as the continuous second longitudinal section 6. It is also understood that the light guide segments 17 of the first longitudinal section 5 have the same design as the continuous first longitudinal section 5 according to the previous embodiments.

According to a further embodiment of the invention according to Figure 6, a Lichtlei ter 22 has a loop portion 23 with ends 24, 24 'converging. The loop section 23 forms the second longitudinal section 6 for generating the second signal light function (side marker light). The remaining arcuate part of the light guide 23 forms the first longitudinal section 5 for generating the first signal light function (daytime running light function). The fact that the ends 24, 24 'of the loop section 23 quasi converge results in a quasi continuous first longitudinal section 5 from the first face 3 to the second face 3', quasi a closed or continuous light signature.

According to a further embodiment of the invention according to FIG. 7, a loop section 23 'of a light guide 26 can be arranged on an inside of the quasi-closed or continuous first longitudinal section 5, while the loop section 23 according to the embodiment according to FIG. 6 on an outside of the first longitudinal section 5 is arranged.

According to a further embodiment of the invention according to FIG. 8, the loop section 23 can also only be used in regions to form the second longitudinal section 6 serve, while another part of the loop section 23 forms an intermediate section 25 from which no light is emitted, shown hatched. No diffuser elements or color changing elements are arranged in this area.

The color change elements 9, 13 are preferably formed from a material with phosphor be standing. The phosphor serves to convert the light into the desired light color.

List of reference symbols

1 light guide

2 light source

3.3 'face

4 light

5 1st longitudinal section

6 2nd longitudinal section

7 diffuser element

8 light-decoupling outer surface

9 1st color change element

10 light

11 diffuser element

12 light-decoupling outer surface

13 2nd color change element

14 light

15 intermediate section

16 light guide segments

17 fiber optic segments

18 reflector element

19 lower contour

20 lateral contour

21 light guides

22 light guides

23.23 'loop section

24.24 'ends

25 intermediate section

26 light guides

H1; H2 main direction of emission

M central axis

F direction of travel

E direction of extent a angle of incidence ß angle of reflection

Y scattering angle range

Claims

1. Lighting device for vehicles with a light guide (1, 21, 22, 26) and a light source (2) arranged on an end face (3) thereof, where in the light guide (1, 21, 22, 26) diffuser elements (7, 11) distributed are arranged to deflect the light (4) in the light guide (1, 21, 22, 26) in the direction of a lateral surface of the light guide (1, 21, 22, 26) and wherein in a region of the lateral surface of the Light guide (1, 21, 22, 26) color change elements (9, 13) are arranged, by means of which the coupled light (4) can be converted from a first wavelength to a second wavelength, characterized in that

- That the light guide (1, 21, 22, 26) is flexible,

- That the light guide (1, 21, 21, 26) in a first longitudinal section (5) of the same first color changing elements (9) for converting the coupled light (4) of the first wavelength into light (10) of the second wavelength to generate a first Signal light function and

- That the light guide (1, 21) has in a second longitudinal section (6) of the same second color changing elements (9) for converting the coupled light (4) of the first wavelength into light (14) of a third wavelength which differs from the light (10) differs from the second wavelength to generate a second signal light function.

2. Lighting device according to claim 1, characterized in that the diffuser elements (7, 11) are arranged so directed in the light guide (1, 21, 22, 26) that the incident on the diffuser elements (7, 11) a coupled light ( 4) is deflected under a radial scattering angle range of 60 ° to 80 °.

3. Lighting device according to claim 1 or 2, characterized in that the diffuser elements (7, 11) are arranged directed in the light guide (1, 21, 22, 26) in such a way that the coupled light incident on the diffuser elements (7, 11) (4) is deflected under an axial scattering angle range (g) of at least 100 °.

4. Lighting device according to one of claims 1 to 3, characterized ge

indicates that the first longitudinal section (5) and the second longitudinal section (6) of the light guide (1, 21, 22, 26) run in a straight line and / or arcuate and that the diffuser elements (7, 11) of the same first longitudinal section (5) and the second longitudinal section (6) are each arranged in such a way that the light (10) in the first longitudinal section (5) in a main radiation direction (H1) and light (14) in the second longitudinal section (6) in a second main radiation direction ( H2) is deflected, the first main emission direction (H1) and the second main emission direction (H2) enclosing an acute or right angle.

5. Lighting device according to one of claims 1 to 4, characterized ge

indicates that the first color change elements (9) are designed such that the converted second wavelength of the light (10) corresponds to a white color for generating a position or daytime running light, and the second color change elements (13) are designed such that the converted The third wavelength of the light (14) corresponds to a yellow color for generating a side marker light.

6. Lighting device according to one of claims 1 to 5, characterized ge

indicates that the second longitudinal section (6) of the light guide (1, 22) directly adjoins the first longitudinal section (5) of the same or that between the first longitudinal section (5) and the second longitudinal section (6) an intermediate section (15, 25) of the light guide (1) is provided which has no diffuser elements (7, 11).

7. Lighting device according to one of claims 1 to 6, characterized in that the diffuser elements (7, 11) are dimen sioned in a pm range.

8. Lighting device according to one of claims 1 to 7, characterized in that the light guide (21) has a reflection element (18) on a side opposite to the longitudinal side of the light output coupling.

9. Lighting device according to claim 8, characterized in that the reflector element (18) and the color change elements (9, 13) are each designed as coatings.

10. Lighting device according to one of claims 1 to 9, characterized in that the second longitudinal section (6) of the light guide (21) are formed by a plurality of light guide segments (16) which alternate in the direction of extent (E) of the light guide (21) are arranged to form optical fiber segments (17) of the first longitudinal section (5).

11. Lighting device according to one of claims 1 to 10, characterized in that the light guide (21, 22, 26) has a loop portion (23, 23 ') with tapering ends (24, 24'), wherein at the En the (24, 24 ') is followed by the first longitudinal section (5) in each case, and that the loop section (23, 23') is at least partially formed by the second longitudinal section (6).

12. Lighting device according to one of claims 1 to 11, characterized in that the light source (1) emits light of blue color.

13. Lighting device according to one of claims 1 to 12, characterized in that the color change element (9, 13) contains a phosphor material.