FR3086368A1 - LIGHT GUIDE LIGHTING DEVICE WITH VARIABLE LIGHTING LENGTH ACCORDING TO REQUIREMENTS - Google Patents

Abstract

A lighting device (DE) comprises: - a source (SP) generating photons, - a light guide (GL) receiving these photons in a first zone (Z1) in order to guide them to a second zone (Z2) for that they participate in a photometric function, and comprising in a chosen location a transverse groove (RT) extending over almost its entire thickness and over its entire width in order to subdivide it into two adjacent parts (PG1-PG2) , and - an opaque plate (PO), having dimensions similar to dimensions of the transverse groove (RT), and is housed in the latter (RT) to allow lighting by photons of a portion of the second zone ( Z2) belonging to one of the parts (PG1-PG2) of the light guide (GL), is unused to allow the entire second zone (Z2) to be illuminated by photons.

Description

LIGHT GUIDE LIGHTING DEVICE WITH VARIABLE LIGHTING LENGTH ACCORDING TO REQUIREMENTS

The invention relates to lighting devices which comprise a photon source and a light guide which must participate in the performance of a photometric function.

In what follows, the term “photometric function” means both a photometric lighting function, a photometric signaling function or a photometric light effect function, possibly decorative.

In certain fields, such as for example that of vehicles, possibly of the automobile type, lighting devices are used comprising a source generating photons and a light guide receiving in a first zone the photons generated in order to guide them towards a second zone. so that they participate in a chosen photometric function. It will be noted that such lighting devices generally constitute front lights, but that they can also be part of optical units ensuring several photometric functions including their own.

In the case of a vehicle, the photometric function of the lighting device can, for example, be chosen from a direction change indicator (or flashing) function and a daytime running light (or DRL ("Daytime") function. Running Light (or Lamp) ”- light signal on automatically when the vehicle is started during the day)).

Currently, when there is a need for several lighting devices having respectively second lighting zones of several lengths, one is forced to use light guides of different lengths and to associate these with electronic cards having different numbers of light-emitting diodes and possibly different lengths and sometimes also to protective boxes and glass of different lengths. This need arises, for example and without limitation, when rules exist, relating to the length of the second lighting zones, which vary from one country to another or from one region to another. This is particularly the case at present with the lighting lengths of the direction indicator function which are not the same in Europe and in the United States of America.

As a result of the aforementioned need, a large variety of parts must be designed, produced and stored, and the supply of which must be managed, which turns out to be expensive and time-consuming. In addition, when lighting devices having second lighting zones of different lengths have to be assembled on the same assembly station, the latter becomes very congested and the probability of assembly error is increased.

The invention therefore aims in particular to improve the situation.

It notably proposes for this purpose a lighting device comprising a source generating photons, and a light guide receiving in a first zone the photons generated in order to guide them to a second zone so that they participate in a chosen photometric function.

This lighting device is characterized by the fact:

- that its light guide comprises in at least one selected location a transverse groove extending over almost its entire thickness and over its entire width in order to subdivide it into two adjacent parts, and

- It also includes an opaque plate, having dimensions similar to the dimensions of the transverse groove, and is housed in the latter in order to allow illumination by the photons generated from a portion of the second zone belonging to one of these two parts of the light guide, is unused in order to allow the entire second zone to be illuminated by the photons generated.

We thus have a lighting device whose lighting length is configurable thanks to the use or not of an opaque plate placed in its light guide.

The lighting device according to the invention may include other characteristics which can be taken separately or in combination, and in particular:

- in a first embodiment, its photon source can comprise either K light diodes, with K> 1, generating photons for one of the two parts of the light guide, or N light diodes, with N> K, generating photons for the two parts of the light guide. In this case, it may include an electronic control circuit controlling the operation of the light diodes which belong to the photon source;

in a second embodiment, its photon source can comprise N light diodes, with N> 2, a first group of K light diodes generating photons for a first of the two parts of the light guide, with K <N, and a second group of N - K others of these light diodes generating photons for a second of the two parts of the light guide. In this case, it may include an electronic control circuit operating either only the first group when the opaque plate is housed in the transverse groove, or the first and second groups when the opaque plate is unused;

- It can include an electronic card on which the photon source is installed;

> the electronic card can include the electronic control circuit;

> the electronic card can be installed in front of the first zone of the light guide;

- The first zone of the light guide can be at least part of a rear face of the latter which is opposite to a front face constituting at least the second zone of the light guide;

- the photometric function can be chosen from a direction change indicator function and a daytime running light (or DRL) function.

The invention also provides an optical unit intended to equip a vehicle and comprising a lighting device of the type presented above.

The invention also provides a vehicle, possibly of the automotive type, and comprising at least one lighting device of the type presented above and / or at least one optical unit of the type presented above.

Other characteristics and advantages of the invention will appear on examining the detailed description below, and the attached drawings (obtained in CAD / CAD ("Computer Aided Design / Computer Aided Drawing"), whence the apparently discontinuous nature of certain lines), on which:

FIG. 1 schematically illustrates, in a sectional view in a longitudinal plane, an example of an optical unit comprising a first embodiment of a lighting device according to the invention, placed in a first configuration,

FIG. 2 schematically illustrates, in a sectional view in a longitudinal plane, the optical unit of FIG. 1 with its lighting device according to the invention, placed in a second configuration, and

- Figure 3 illustrates schematically, in a sectional view in a longitudinal plane, an example of an optical unit comprising a second embodiment of a lighting device according to the invention, placed in a first configuration.

The object of the invention is in particular to propose a configurable ED lighting device intended to provide a chosen photometric function.

It is considered in what follows, by way of nonlimiting example, that the lighting device DE is intended to be part of a vehicle of the automobile type, such as for example a car. But the invention is not limited to this application. Indeed, the lighting device DE can be an equipment which can be added and used in numerous systems or which can be part of other equipment which is itself part of a system. Thus, the DE lighting device can be part of any vehicle (land, sea (or river), or air), of any installation, including of industrial type, of any device ( or system), including consumer type, and any building, for example.

Furthermore, it is considered in what follows, by way of nonlimiting example, that the lighting device DE is intended to be part of an optical unit BO constituting a headlight (or headlight) before a motor vehicle and providing at least two photometric functions. But it could constitute a vehicle front light, for example.

In addition, taking into account the above choices, it is considered in what follows, by way of nonlimiting example, that the lighting device DE is intended to provide a photometric signaling function. For example, this is a direction change indicator (or flashing) function. But it could also be a daytime running light (or DRL) function. But the invention is not limited to this application. Indeed, the lighting device DE, according to the invention, is a light device which can provide a photometric signaling or lighting or light effect (possibly decorative) function.

There is diagrammatically illustrated in FIGS. 1 and 2, a part of an optical unit BO of the vehicle, comprising a first embodiment of a lighting device DE according to the invention, placed respectively in first and second different configurations , which we will come back to later. Also schematically illustrated in FIG. 3, a part of this same optical unit BO of the vehicle, comprising a second embodiment of a lighting device DE according to the invention, placed in a first configuration.

The optical unit BO (here a front projector) comprises, in particular, a housing BB delimiting with a protective glass GP a cavity housing in particular a lighting device DE according to the invention.

The BB box is intended, here, to be secured to a front part of the body of a vehicle. It is made of a rigid material, such as for example a plastic or synthetic material. In this case, it can be produced by molding.

The GP protective glass can, for example, be made of glass or plastic. It is fixedly secured to a front part of the housing BB, for example by gluing, welding or screwing. Furthermore, it can optionally have one or more colors chosen from crystal white, red and orange (or amber).

As illustrated (at least partially) in FIGS. 1 and 2, a lighting device DE, according to the invention, comprises at least one source SP, a light guide GL and an opaque plate PO.

Note that when the lighting device DE is an equipment in itself, it also comprises a housing delimiting with a protective glass a cavity housing in particular its source SP, its light guide GL and its opaque plate PO.

The SP source is arranged so as to generate photons which define a light, for example of white or orange color or even amber.

For example, and as illustrated without limitation in FIGS. 1 to 3, this source of photons SP may include light diodes DLj. The latter (DLj) can be light-emitting diodes, of the conventional type (or LED (“Light-Emitting Diode”)) or of organic type (or OLED (“Organic Light-Emitting Diode”)), or else laser diodes.

Also as shown without limitation in FIGS. 1 to 3, these light-emitting diodes DLj can be installed on an electronic card CE, for example with integrated or printed circuits, and possibly of the PCB (“Printed Circuit Board”) type. This electronic card CE is then part of the lighting device DE. In the example illustrated, it is fixedly secured to an internal face of the housing BB.

The operation of the photon source SP is controlled by an electronic control circuit CC which can, for example and as illustrated without limitation in FIGS. 1 to 3, form part of the electronic card CE and therefore of the lighting device DE, and which we will come back to later.

The light guide GL is arranged so as to receive in a first zone Z1 the photons generated by the source SP in order to guide them to a second zone Z2 so that they participate in a chosen photometric function.

In addition, this light guide GL comprises in at least one chosen location a transverse groove RT which extends over almost its entire thickness and over its entire width in order to subdivide it into two parts PGj (j = 1 or 2 ) adjacent.

In FIGS. 1 to 3 the directions x1, x2 and x3 are respectively the directions of the length, the thickness and the width of the light guide GL.

The opaque plate PO has dimensions which are similar to the dimensions of the transverse groove RT, so that it can be housed therein in a first configuration illustrated in FIGS. 1 and 3. In addition, this opaque plate PO is either housed in the transverse groove RT in order to allow illumination by the photons generated of a portion PZj of the second zone Z2 belonging to one of the two parts PGj of the light guide GL (as illustrated in FIGS. 1 and 3), is unused in order to allow illumination of the whole (PZ1 + PZ2) of the second zone Z2 by the photons generated.

The lighting device DE is thus configurable because when the opaque plate PO is used (FIGS. 1 and 3) only a portion PZj of the second zone Z2 is illuminated (which constitutes a first configuration), and when the opaque plate PO is not used (FIG. 2), the entire second zone Z2 is illuminated (which constitutes a second configuration). In other words, in the second configuration (not using the opaque plate PO), lighting is obtained over the entire length (along x1) of the light guide GL, while in the first configuration (using the opaque plate PO ) lighting is obtained over a length (along x1) which is reduced compared to the total length of the light guide GL.

It will be understood that the opaque plate PO prevents the photons which have entered the first part PG1 of the light guide GL from passing into the second part PG2 of the light guide GL, and therefore prevents the lighting of the second portion PZ2 of the second zone Z2 of the light guide GL.

It should be noted that one could define several (at least two) transverse grooves RT in several selected locations of the light guide GL in order to increase the number of possible lighting lengths with the same lighting device DE. Thus, with two transverse RT grooves we obtain three different lighting lengths (small, medium and total).

At least two embodiments of the DE lighting device can be envisaged.

In a first embodiment, illustrated in FIGS. 1 and 2, the photon source SP comprises a number of light diodes DLj which varies according to the configuration (with or without an opaque plate PO). More precisely, this number is either equal to K, with K> 1, as illustrated in FIG. 1 (first configuration), and in this case the K light diodes DL1 (j = 1) generate photons for one (PG1 ) of the parts PGj of the light guide GL to obtain a reduced lighting length on the portion PZ1 of the second zone Z2, ie equal to N, with N> K, as illustrated in FIG. 2 (second configuration), and in this case the N light diodes DL1 and DL2 (j = 2) generate photons for the two parts PG1 and PG2 of the light guide GL to obtain a complete lighting length over the whole (PZ1 + PZ2) of the second zone Z2 .

In the example illustrated without limitation in FIG. 1 K = 10, and in the example illustrated without limitation in FIG. 2 N = 14. Here, the K light diodes which are placed to the left of the opaque plate PO are referenced DL1 (j = 1), and the N - K other light diodes which are placed to the right of the opaque plate PO are referenced DL2 (j = 2). But the numbers K and N can take any values, since K is greater than or equal to one (1) and N is strictly greater than K. We can thus have K = 1 and N = 2, or K = 2 and N = 3, for example.

It will therefore be understood that in this first embodiment, the number of light diodes DLj (N or K) of the photon source SP is chosen as a function of the desired lighting length. For this purpose, it is possible, for example and as illustrated without limitation, to use two identical CE electronic cards except for the numbers of light diodes DLj (N or K) which they comprise respectively.

Furthermore, in this first embodiment, the lighting device DE comprises an electronic control circuit CC which controls the operation of the light diodes DLj belonging to the photon source SP. In this case, the same electronic control circuit CC can be used for the two configurations with N or K light diodes DLj, and therefore on the two possible CE electronic cards.

In a second embodiment, illustrated in FIG. 3, the photon source SP comprises a fixed number N of light diodes DLj, with N> 2 for the two configurations. These N light diodes DLj are subdivided into first and second groups. The first group includes K light diodes DL1 (j = 1) which generate photons for a first PG1 of the two parts PGj of the light guide GL, with K <N. The second group includes the N - K other light diodes DL2 0 = 2) which generate photons for a second PG2 of the two parts PGj of the light guide GL.

The first group of K light diodes DL1 therefore generates photons which make it possible to obtain a reduced lighting length on the first portion PZ1 of the second zone Z2, while the second group of N - K light diodes DL2 generates photons which allow a reduced lighting length to be obtained on the second portion PZ2 of the second zone Z2.

Furthermore, in this second embodiment the lighting device DE comprises an electronic control circuit CC which operates either only the first group when the opaque plate PO is housed in the transverse groove RT (first configuration illustrated in FIG. 3 ), or the first and second groups when the opaque plate PO is unused (second configuration equivalent to that illustrated in FIG. 2). Consequently, in the first configuration, a reduced lighting length is obtained over the first portion PZ1 of the second zone Z2, while in the second configuration, a complete lighting length is obtained over the whole of the second zone Z2 (at know its first PZ1 and second PZ2 portions).

In this second embodiment, it is therefore possible, for example and as illustrated without limitation, to use a single electronic CE card comprising N light diodes DLj and an electronic control circuit CC which is configured so as to control the operation either by itself first group of K light-emitting diodes DL1, i.e. of the first group of

K DL1 light diodes and the second group of N - K other DL2 light diodes, depending on the configuration required.

It will be noted that in an alternative embodiment of the second embodiment, it can be envisaged that the electronic control circuit CC operates either only the first group (DL1) when the opaque plate PO is housed in the transverse groove RT, in order to obtain a first reduced lighting length on the first portion PZ1 of the second zone Z2, i.e. the first and second groups (DL1 + DL2) when the opaque plate PO is not used, to obtain a complete lighting length over the entire second zone Z2 (namely its first PZ1 and second PZ2 portions), or even only the second group (DL2) when the opaque plate PO is housed in the transverse groove RT, to obtain a second reduced lighting length on the second portion PZ2 of the second zone Z2.

It will also be noted, as illustrated without limitation in FIGS. 1 to 3, that the electronic card CE can be installed in front of the first zone Z1 of the light guide GL. This allows, if desired, to place the N light diodes DLj in front of this first zone Z1, for example by spacing them from one another in a substantially constant manner, so as to obtain a homogeneous lighting (of a substantially constant intensity) regardless of the location considered of the portion PZj of the second zone Z2 to be illuminated.

It will also be noted, as illustrated without limitation in FIGS. 1 to 3, that the first zone Z1 of the light guide GL can be at least part of the rear face FR of the latter (GL), which is opposite to its front face FV which constitutes at least the second zone Z2 of the light guide GL. This makes it possible to make the transfer of photons from the first zone Z1 to the second zone Z2 of the light guide GL more direct. However, it could be envisaged that the first zone Z1 of the light guide GL is placed at one of the two ends (longitudinal) of the latter (GL).

In the two examples illustrated without limitation in FIGS. 1 to 3, the first zone Z1 extends over the entire rear face FR and the second zone Z2 extends over the entire front face FV. However, the first zone Z1 could extend over part of the rear face FR and / or the second zone Z2 could extend over part of the front face FV.

It will also be noted, as illustrated without limitation in FIGS. 1 to 3, that the rear face FR may include three-dimensional (or 3D) structures suitable for introducing the photons into the light guide GL in preferred directions so that they preferentially reach places in the second zone Z2 which are a function of the place in the first zone Z1 through which they entered. Such 3D structures can, for example, be prisms, ribs, gadroons (species of ribs) or studs.

It will also be noted that the possible electronic control circuit CC can be arranged so as to operate the light diodes DLj one after the other, in order to create a scrolling effect (from right to left or from left to the right) as required. But it is not compulsory. Indeed, it could make them work all together (either DL1, or DL1 + DL2, or even possibly only DL2 (in the variant)).

For example, the light guide GL can be produced by molding a material such as polycarbonate (or PC) or poly methyl methacrylate (or PMMA). It can, moreover, possibly be of the so-called “flat” (or “fiat guide”) type.

Also for example, the optical plate PO can be produced by molding a material such as polyethylene (or PE) or polypropylene (or PP) or even polycarbonate (or PC).

Claims (10)

1. Lighting device (DE) comprising a source (SP) generating photons, and a light guide (GL) receiving in a first zone (Z1) said generated photons in order to guide them to a second zone (Z2) for that they participate in a chosen photometric function, characterized in that said light guide (GL) comprises in at least one chosen location a transverse groove (RT) extending over almost its entire thickness and over its entire width in order to subdivide it into two adjacent parts (PGj), and in that it comprises an opaque plate (PO), having dimensions similar to the dimensions of said transverse groove (RT), and is housed therein (RT) in order to allow illumination by said generated photons of a portion of said second zone (Z2) belonging to one of said parts (PGj) of the light guide (GL), is unused in order to allow illumination of the whole of said second zone ( Z2) by said photons generated. 2. Device according to claim 1, characterized in that said photon source (SP) comprises either K light diodes (DL1), with K> 1, generating photons for one (PG1) of said parts (PGj) of the guide of light (GL), or N light diodes (DLj), with N> K, generating photons for said two parts (PGj) of the light guide (GL), and in that it comprises an electronic control circuit ( CC) controlling the operation of said light diodes (DLj) belonging to said photon source (SP). 3. Device according to claim 1, characterized in that said photon source (SP) comprises N light diodes (DLj), with N> 2, a first group of K light diodes (DLj) generating photons for a first (PG1 ) of said parts (PGj) of the light guide (GL), with K <N, and a second group of N - K others of these light diodes (DLj) generating photons for a second (PG2) of said parts (PGj) of the light guide (GL), and in that it comprises an electronic control circuit (CC) operating either only said first group when said opaque plate (PO) is housed in said transverse groove (RT), or said first and second groups when said opaque plate (PO) is unused. 4. Device according to one of claims 1 to 3, characterized in that it comprises an electronic card (CE) on which is installed said photon source (SP). 5. Device according to claim 4 taken in combination with claim 2 or 3, characterized in that said electronic card (CE) comprises said electronic control circuit (CC). 6. Device according to claim 4 or 5, characterized in that said electronic card (CE) is installed in front of said first zone (Z1) of the light guide (GL). 7. Device according to one of claims 1 to 6, characterized in that said first zone (Z1) of the light guide (GL) is at least part of a rear face (FR) of the latter (GL), opposite a front face (FV) constituting at least said second zone (Z2) of the light guide (GL). 8. Device according to one of claims 1 to 7, characterized in that said photometric function is chosen from a direction change indicator function and a daytime running light function. 9. Optical unit (BO) for a vehicle, characterized in that it comprises a lighting device (DE) according to one of the preceding claims. 10. Vehicle, characterized in that it comprises at least one lighting device (DE) according to one of claims 1 to 8 and / or at least one optical unit (BO) according to claim 9.