DE19654358C2 - Ambient lighting for cars - Google Patents

Description

The invention relates to a lighting arrangement, in particular to illuminate the interior or storage trays of motor vehicles or the like, with at least one punctiform light source, preferably an LED, the Light is fed into a light guide and from one Exit side of the light guide emerges over a large area, whereby the back of the Light guide is designed to scatter light.

Such a lighting arrangement is, for example through EP 0 515 921 A2.

As is known, the passenger interior of vehicles e.g. B. are brightly lit with the help of a lamp arrangement, whose lamp automatically when the door is opened or by manual Pressing lights up. The bright lighting can or may due to annoying light reflections and the limited Lamp life not switched on when driving at night stay.

It is also known to find a passenger in the Switching elements located in the passenger compartment as a result facilitate that shine permanently in these switching elements de, mostly point light sources such. B. LEDs (light emitting diode) are integrated. These light sources must on the one hand shine so brightly that the switching elements can be found are bar, but on the other hand be so weak that they do not blind or disturb the passenger. Hence the driving  does the corresponding switching element in the dark? know, but mostly not his finger, which he attached to the Would like to introduce switching element for actuation.

To promote the well-being of a passenger at night lighting is also desirable, the passenger compartment of the vehicle permanently and not can brighten disruptively. The known lamps described Arrangements cannot be used for this as lamps and emit LED's punctiform luminous images, which disturb light reflections.

From the above-mentioned EP 0 515 921 A2 is lighting device arrangement known, in the light in the end face egg is fed in and on a light guide exit from the light guide again. On the the Back of the light guide facing away from the light exit side reflectors are introduced in the form of prisms that deflect the light so strongly that it is on the light exit side emerges from the light guide. The prisms are equidistant stant on the back of the rod-shaped light guide brings, being in different directions by the light conductor going rays on the prisms in different Direction reflected or distracted. Most of it of the light fed into the light guide already at the er Most pass through the prisms and is reflected takes in the known lighting arrangement from Light guide emerging light intensity with the distance from from the feed end face, so that over the large area Light exit surface Light not with the same light intensity exits.

The present invention is therefore based on the object a lighting arrangement of the type mentioned going to train that over the large-area outlet surface of the light guide the light with the same as possible Luminous intensity emerges.

This object is achieved in that the Degree of light scatter of the back of the light guide with the Distance from the at least one light source increases.

Since at a greater distance from the light source due to the height more light from the light guide emerges and at the same time the luminosity with the distance decreases from the light source, so - at least for that human eye - over the entire exit surface of the Light guide is almost uniform in intensity Illuminated image can be achieved.  

This lighting arrangement according to the invention, which also as "Ambient lighting" can be called, egg ne non-distracting brightening of the passenger interior Night or darkness, whereby through the large area point of the light fed into the light guide shaped light source is a non-reflective, permanent Night light is created. In contrast to the known one point lighting in a switching element are not only the individual switching elements can be found, but the Driver can be stretched out to operate the switch Guide your hand or finger accurately. The light of the point light source is large within the light guide distributed and sent. That is on in the light guide fed or captured light due to total reflection and can e.g. B. only at certain points on the exit egg exit the light guide. In contrast to a point light source alone results according to the invention a large-area lighting phenomenon with which the interior can be subtly brightened. This Aufhel lung increases the well-being of a vehicle occupant Night driving. In addition, LEDs indicate, especially when they are on permanently operation, a significantly longer compared to incandescent lamps Lifespan.

In a preferred embodiment, this comes out of the box exit side of the light guide through a light Light diffuser such. B. a light diffuser. With With the help of this light diffuser, this can be removed from the light guide shone light in its luminosity, at least for that human eye to be more evenly distributed.  

In another preferred development, the re side of the light guide in the transverse direction and over the entire Width of the light guide extending elevations and / or ver deepening through which the guided or in the light guide trapped light towards the exit side of the Optical fiber is deflected.

In another particularly advantageous development has the back of the light guide depressions and / or Elevations, their extension in the transverse direction of the light conductor is smaller than the width of the light guide.  

In a particularly advantageous embodiment of this Wei terbildung are adjacent in the longitudinal direction of the light guide te depressions and / or elevations in the transverse direction in each case arranged offset to each other so that in the longitudinal direction of the No continuous light line can occur.

In particularly preferred configurations, the Ab stood in the longitudinal direction of adjacent depressions and / or Surveys with their distance from the at least one Light source. This reduces the degree of light scattering Back with the distance from the light source to what to egg uniform light pattern over the entire exit side of the light guide contributes.

In order to improve the illuminated image even further, in one different configuration of the opening angle of the wells or surveys with respect to the longitudinal direction of the light guide with its distance from the at least one light source vari ieren.

Also in that the depth of the recess or the height of the Elevations with the distance from the at least one light source varies, the uniformity of the emitted Illuminated image can be improved.

Another particularly advantageous development is the back of the light guide roughened. Such Surface is the result of treating the back e.g. B. sandblasting, etching or extruding.  

If the degree of roughness of the back with the distance increases from the at least one light source, one relatively uniform radiation from the Light guide emerging light can be achieved.

To the light of the preferably punctiform light source in Introducing the light guide is advantageous tion form from the at least one light source radiated light into one end of the light guide bar.

In a particularly preferred development of this embodiment This is from the at least one light source light entering through a feed opening in a forehead side can be fed into the light guide. Preferably there is the LED at such a distance before or in the feed solution opening arranged that their focus within the feed opening.

To feed the light of at least one light source To optimize le is min at least one, preferably two, conical or curved Infeed areas provided.

To ensure the immediate exit of the injected into the light guide Most light from the light source in the area of the feed opening prevention, the infeed opening must be at least at least one, preferably two, conical or curves shaped outer surfaces. The cone angle is like this chosen that as much light as possible on the outer surfaces of the Is guided and not immediately, d. H. without one only reflection at the end of the light guide, emerges.  

In a preferred embodiment, this is in the light conductor-fed light via an oblique front face reflectable on the outlet side in the infeed area. This sloping edge reflects a large part of the otherwise Light guide leaving light without reflection in the longitudinal direction into the light guide. This has the advantage that the light source from the outside is not a bright punctiform Light source appears.

The at least one light source in is particularly preferred a further embodiment through an aperture, preferred wise by resistance, obscured from the outside. E.g. can the series resistor required for an LED anyway these can be arranged to conceal the outside.

Defined around the light guide to the housing or one to arrange at least one circuit board carrying light source NEN, the light guide is in special embodiments in centered in a housing and arranges the light guide center the PCB to the housing.

Further advantages of the invention result from the Be writing and drawing. Likewise, the above mentioned and invented the features further invented in accordance with the invention individually for themselves or for several in be arbitrary combinations are used. The shown and The embodiments described are not intended to be final Understand enumeration, but rather have exemplary th character for the description of the invention.

Show it:

Figure 1 in a perspective view obliquely from above a first embodiment of a lighting arrangement.

Figure 2 shows an off-center longitudinal section of the lighting arrangement shown in Figure 1;

Fig. 3 is a longitudinal section through the center plane of the lighting assembly shown in Fig. 1;

Fig. 4 is a plan view of the back of the light guide of the illumination assembly of Figs. 1 to 3;

FIG. 5 shows a side view with an enlarged detailed view of the light guide shown in FIG. 4;

FIG. 6 shows an end view of the light guide shown in FIGS. 4 and 5 corresponding to VI in FIG. 4;

Fig. 7 is a sectional view with a schematic beam path in the light-feeding portion of the light guide shown in Figures 4 to 6 according to VII-VII in Fig. 6.;

Fig. 8 is a plan view of the rear of another light guide; and

Fig. 9 is a side view of the light guide shown in Fig. 8.

The generally designated in Fig. 1 with 1 Beleuchtungsanord voltage comprises a housing 2 with a front and rear end wall 2 a, 2 b, and c with side walls 2, 2 d. In a bilateral side groove 3 in the side walls 2 c, 2 d, a Lei terplatte 4 is inserted, and in a through the walls 2 a- 2 d defined receptacle 6 in the housing 2 is a light guide 5 until it rests on system projections 7 , 8th inserted. The light guide 5 is held in this system by two gabelförmi ge projections 9 , 10 at its two longitudinal ends. The housing 2 is closed to the outside by a light diffuser 15 designed as a scattered light disc, the inward-facing inner side 16 of which is provided with a diffuse surface structure and the outward-facing outer side 17 has a smooth surface.

As shown in FIG. 2, the two fork-shaped projections 9 engage through an opening 11 in the printed circuit board 4 and lie behind a wall 13 of a housing opening 12 . By on the system projection 7 on the one hand and through the wall 13 on the other hand in the housing 2 set before jump 9 is also penetrated by the circuit board 4 in the housing 2 in their position fixed and defined aligned tet. In this state, a bore 18 in Lei terplatte 4 is aligned with a bore 19 in the front end wall 2 a of the housing 2 , so that a contact pin 20 in both Boh stanchions 18 , 19 can be inserted. The contact pin 20 is in electrical contact with an electrical circuit on the printed circuit board 4 and at the other end projects into a plug receptacle 21 in the housing 2 that is accessible from the outside.

The light guide 5 is held in its system on the other Anlagevor jump 8 by means of a locking paragraph 22 which engages behind a wall 25 of a housing opening 24 in the rear end wall 2 b.

Fig. 3 shows that on the printed circuit board 4 one or more LEDs 26 and corresponding control ICs or series resistors 27 are provided. To feed the light of the LED 26 into the light guide 5 , the LED 26 is arranged in a corresponding to the feed opening 28 in an end face 31 of the light guide 5 . The the light diffuser 15 facing away from back 33 of the light guide 5 is provided with a light true the surface structure is provided such that the ladder in the light 5 injected and trapped in this ge by total reflection light due to the diffusing back 33 towards the opposite discharge side 43 of the light guide 5 distracted and can exit from this. Through the light diffuser 15 , the light emerging from the lighting arrangement 1 appears to an observer over the entire exit surface of the light diffuser 15 with almost the same luminosity. So that the punctiform LED 26 from the outside is not perceived as possible as a luminous light spot, the LED 26 is arranged by an aperture on the printed circuit board 4 , for. B. covered by a series resistor 30 of the LED 26 to the outside such that the punctiform LED 26 is covered from the outside.

According to Fig. 4, the light guide 5 side on its rear 33 z 5 extending, parallel grooves 35 across the entire width of the light guide. B. in the form of fur on that represent a grating for the light fed into the light guide 5 . In order that the light of the LED 26 fed into the light guide 5 in the feed area 34 emerges with the same intensity over the entire length of the light guide 5 , the distance d between adjacent depressions decreases with the distance from the LED 26 , ie the distance d _{1 is} close the front end face 31 is greater than the distance d ₂ near the rear end face 32 . Since the fed-in light only exits the light guide 5 where depressions 35 are provided, despite the high light intensity near the front end face 31, light with a low intensity occurs due to the few depressions 35 . From the light guide 5 near the rear face 32 , where the light intensity is lower, but the number of recesses 35 is higher, light emerges with a comparable intensity. In this way, a luminous image that is at least uniform for the human eye can be achieved over the entire length or area of the light guide 5 and the light diffuser 15 .

Not only by the distance d between adjacent recesses 35 , but also by their depth and by their angle to the back 33 and by a surface treatment of the back 33 by z. B. sandblasting, etching, extruding, etc., the light exit from the light guide 5 can be adjusted or changed. The degree of scattering for the light guided in the light guide 5 preferably increases with the distance from the LED 26 .

FIGS. 6 and 7 show the optical waveguide 5 in-feed area 34. The LED 26 is arranged in a feed opening 37 , which is formed by a cylindrical section 42 , a first (flat) inner cone 38 and a second (steep) inner cone 39 . The Einspeisungsöff opening 37 is formed on the outside by a first (steep) outer cone 40 and a second (flat) outer cone 41 . The beam path of the light shown in FIG. 7 in the feed area 34 shows that the light of the LED 26 is broken off by the flat inner cone 38 into an area near the feed area 34 and through the steep inner cone 39 into a more distant area of the light guide 5 . Due to the flat and steep outer cone 40 , 41 , the light fed via the cylindrical section 42 is reflected far into the light guide 5 . Due to this geometry, the light is fed into the light guide 5 over the entire length thereof.

FIGS. 8 and 9 show an optical waveguide 50, side by its rear 51 protuberances 52 protrude. In the transverse direction of the light conductor 50 , a plurality of elevations 52 are arranged in a row, the elevations 52 of two adjacent rows, for. B. 53 and 54 are offset from one another in order to prevent a continuous light line in the longitudinal direction. The elevations 52 act like the recesses 35 as scattering centers for the light guided in the light guide 50 , which is thereby deflected towards the exit side 57 .

As shown in FIG. 9 in particular, the distance d between adjacent rows of elevations 52 decreases with the distance from the LED or from the feed region 55 . This results in an essentially identical luminous intensity — seen over the length of the light guide 50 . Thus, the light source is shielded to the outside as possible and blister-masked, the light guide 50 has a sloping forward edge 56, where not without reflection through a large part of the light emitted from the LED light in the feeding portion 55 from the light can emerge 50 conductors. An LED cannot be recognized from the outside or can hardly be seen as a point light source.

Claims (18)

1. Lighting arrangement ( 1 ), in particular for illuminating the interior or storage trays of motor vehicles or the like, with at least one point light source, preferably an LED ( 26 ), the light of which is fed into a light guide ( 5 ; 50 ) and from a Exit side ( 43 ; 57 ) of the light guide ( 5 ; 50 ) emerges over a large area, the opposite side of the exit side ( 43 ; 57 ) ( 33 ; 51 ) of the light guide ( 5 ; 50 ) being light-scattering, characterized in that Degree of light scattering of the back ( 33 ; 51 ) of the light guide ( 5 ; 50 ) increases with the distance from the at least one light source. 2. Lighting arrangement according to claim 1, characterized in that the light emerging from the exit side ( 43 ; 57 ) of the light guide ( 5 ; 50 ) passes through a light diffuser ( 15 ). 3. Lighting arrangement according to claim 1 or 2, characterized in that the back ( 33 ) of the Lichtlei ters ( 5 ) in the transverse direction and over the entire width of the light guide ( 5 ) has elevations and / or depressions ( 35 ). 4. Lighting arrangement according to one of claims 1 to 3, characterized in that the back ( 51 ) of the light guide ( 50 ) has depressions and / or elevations ( 52 ), the extent of which in the transverse direction of the light guide ( 50 ) is smaller than the width of the light guide ters ( 50 ). 5. Lighting arrangement according to claim 4, characterized in that in the longitudinal direction of the light guide ( 50 ) adjacent depressions and / or elevations ( 52 ) are arranged offset to one another in the transverse direction. 6. Lighting arrangement according to one of claims 3 to 5, characterized in that the distance from adjacent in the longitudinal direction of depressions ( 35 ) and / or elevations ( 52 ) decreases with their distance from the at least one light source. 7. Lighting arrangement according to one of claims 3 to 6, characterized in that the opening angle of the recesses ( 35 ) or elevations ( 52 ) with respect to the longitudinal direction of the light guide ( 5 ; 50 ) with their Ab from the at least one light source varies. 8. Lighting arrangement according to one of claims 3 to 7, characterized in that the depth of the indentations ( 35 ) or the height of the elevations ( 52 ) varies with the distance from the at least one light source. 9. Lighting arrangement according to one of claims 1 to 8, characterized in that the back ( 33 ; 51 ) of the light guide ( 5 ; 50 ) is roughened. 10. Lighting arrangement according to claim 9, characterized in that the degree of roughness of the back ( 33 ; 51 ) increases with the distance from the at least one light source. 11. Lighting arrangement according to one of the preceding claims, characterized in that the light emitted by the at least one light source in ei ne end face ( 31 ) of the light guide ( 5 ; 50 ) is feed bar. 12. Lighting arrangement according to claim 11, characterized in that the light emerging from the at least one light source via a, preferably near the focal point of the light source arranged, feed opening ( 37 ) in an end face ( 31 ) in the light guide ( 5 ; 50 ) can be fed. 13. Lighting arrangement according to claim 12, characterized in that within the feed opening ( 37 ) at least one conical or curved feed area ( 38 , 39 ) is provided. 14. Lighting arrangement according to claim 12 or 13, characterized in that the feed opening ( 37 ) is surrounded by at least one conical or curved outer surface ( 40 , 41 ). 15. Lighting arrangement according to one of the preceding claims, characterized in that the light fed into the light guide ( 5 ; 50 ) is reflectable via an end bevel edge ( 56 ) on the outlet side in the feed region ( 34 ). 16. Lighting arrangement according to one of the preceding claims, characterized in that the at least one light source is covered by an aperture, preferably by a resistor ( 30 ), to the outside. 17. Lighting arrangement according to one of the preceding claims, characterized in that the light guide ( 5 ; 50 ) in a housing ( 2 ) is arranged centered. 18. Lighting arrangement according to one of the preceding claims, characterized in that the light guide ( 5 ; 50 ) a circuit board ( 4 ) to a housing ( 2 ) centered.