Signalling assembly for a vehicle for obstacle detection

Abstract

The invention relates to a signalling assembly (1) for a vehicle (2), the assembly comprising a left-hand front optical unit (22) and a right-hand front optical unit (24), the optical units together being capable of covering a field of detection having an angular amplitude (L) extending between a first direction (d1) and a fourth direction (d4). The left-hand front optical unit (22) is configured so that, when no indicator light is active, it generates a first light beam (222) that covers the angular amplitude (L) of the field of detection by itself alone and the right-hand front optical unit (24) is configured so that, when no indicator light is active, it generates a second light beam (242) that covers the angular amplitude (L) of the field of detection by itself alone.

Description

DESCRIPTION Title of the invention: Vehicle signaling assembly enabling obstacle detection

[0001] The present invention relates to the fields of automobiles and optics. More specifically, it relates to a vehicle signaling assembly.

[0002] In recent vehicles, light-emitting diode assemblies are commonly used to create external lighting devices such as signal lights. These diode assemblies allow energy savings while providing vehicles with light signatures specific to each brand, and are expected to be future means of vehicle communication with each other or with road infrastructure, thanks to optical communication technology such as VLC (for "Visible Light Communication") for example.

[0003] Indeed, the bandwidth of a conventional light-emitting diode with a side of one millimeter is approximately 5 MHz (MegaHertz), and is therefore sufficient to enable light communication between vehicles or between a vehicle and a road infrastructure. However, this bandwidth is not suitable for obstacle detection applications. Such an application is generally carried out optically in certain vehicles using LiDAR (Light Detection And Ranging) technology based on laser sensors allowing analysis of the reflected signal over a bandwidth of the order of several tens of MegaHertz, or even a few hundred MegaHertz. LiDAR systems embedded in vehicles are nevertheless very expensive.

[0004] The inventors have however discovered that such an obstacle detection application is possible by using light-emitting diodes, by increasing their bandwidth, either by equalization techniques, or by using diodes of a size smaller than 300 micrometers, or a combination of these techniques. This application may require the use of a specific type of driver such as a high-speed driver or a laser driver. The light-emitting diodes used for this application are also blue-light emitting diodes adapted to emit white light.

[0005] Thanks to this discovery, the inventors have made it possible to replace the expensive LiDAR technology in a vehicle with specific signaling devices based on light-emitting diodes, which perform, in addition to regulatory signaling functions, an obstacle detection function.

[0006] However, to enable a vehicle to maintain the same light signature under different driving conditions, very often in the same vehicle headlight unit, the indicator light, the daytime running light and / or the positioning light may share the same exit surface. In this context, regulatory standards imply that when a driver of the vehicle activates the indicator light, the daytime running light or the positioning light sharing the same exit surface as this indicator light is automatically switched off so as not to impede the perception of the indicator light by other road users.

[0007] This means that when the obstacle detection application designed by the inventors is integrated into this optical unit, then when the flashing light is activated, the blue light-emitting diodes used by the application do not operate, and therefore do not participate in the obstacle detection implemented by all the optical units of the vehicle. More precisely, the obstacle detection application only relies on the light emitted by the blue light-emitting diodes of the optical unit when the indicator of this optical unit is not activated, which restricts the obstacle detection field of the vehicle. In particular, when the right indicator is activated, some obstacles close to the vehicle on its right are not detected, and conversely when the left indicator is activated, some obstacles close to the vehicle on its left are not detected.

[0008] The present invention aims to remedy at least in part the aforementioned drawbacks by providing a vehicle signaling assembly, in which the optical units have the same output surface for a flashing light and a positioning light or a daytime running light, this signaling assembly making it possible to maintain a sufficient obstacle detection field when one of the flashing lights is activated.

[0009] To this end, the invention proposes a signaling assembly for a vehicle, comprising a left front optical unit comprising a left front flashing light and a right front optical unit comprising a right front flashing light, each optical unit further comprising means for transmitting a high-frequency coded light signal to the outside of the vehicle, and means for receiving such a light signal arriving from the outside of the vehicle, the receiving means comprising means for coupling to obstacle detection means of the vehicle, the transmission means of the left front optical unit being configured, when no flashing light is activated, to generate a first light beam extending between a first direction forming a left outer terminal and a second direction forming a left inner terminal, the transmission means of the right front optical unit being configured, when no flashing light is activated,to generate a second light beam extending between a third direction forming a right inner terminal and a fourth direction forming a right outer terminal, the emission means of the front left optical unit and the emission means of the front right optical unit being capable of:, - on the one hand to cover together a detection field having a width detection between the first direction and the fourth direction in a predetermined portion of a sharpness zone of the receiving means of the optical units, greater than or equal to a minimum detection width, the detection width being measured parallel to a front face of the vehicle, and - on the other hand to provide a daytime running light and / or positioning light function, the signaling assembly being characterized in that, at least when the left flashing light is activated, the emission means of the right front optical unit are configured to cover by themselves the minimum detection width in the predetermined portion, and, at least when the right flashing light is activated, the emission means of the left optical unit are configured to cover by themselves the minimum detection width in the predetermined portion.

[0010] The sharpness zone is comprised between, on the one hand, the sharp plane capable of being formed closest to the vehicle in front of it on an image taken by the reception means of the front right or left optical units, and on the other hand, the sharp plane capable of being formed furthest from the vehicle in front of it on an image taken by the reception means of the front right or left optical units. The distance between these two planes corresponds to the depth of field of the reception means of the front right or left optical units.

[0011] In the signaling assembly according to the invention, the positioning or daytime running lights are not permitted to operate at the same time as the flashing lights, because their output surfaces are the same or too close to each other.

[0012] When no flashing light is activated (i.e. switched on), the emission means of the optical units together cover a light field extending from the first direction to the fourth direction. The corresponding detection width is therefore between this first and fourth direction, and extends more or less between these two directions depending on the distance to the vehicle and the arrangement of the means of receiving the optical units.

[0013] The detection width is measured parallel to the road and to the front of the vehicle, in the area of ​​sharpness of the receiving means, the predetermined portion being defined for example between a first predetermined distance in front of the vehicle, and a second predetermined distance in front of the vehicle further from the first predetermined distance in relation to the vehicle. The detection width in this predetermined portion must always be greater than the minimum detection width, which must make it possible to detect obstacles in front of the vehicle, at a distance fairly close to it.

[0014] For example, the predetermined portion begins at the hyperfocal distance of the receiving means divided by two. The predetermined portion has, for example, a depth of 50 centimeters (cm) in the direction orthogonal to the front face of the vehicle. Any measurement of the detection width of the transmitting means of the right or left front optical unit, after the hyperfocal distance of the receiving means divided by two, must therefore be greater than a minimum detection width, for example 50 cm, in this predetermined portion.

[0015] In another example, the minimum detection width is greater than or equal to 2 meters (m) at the intersection of the first and second light beams, when they operate together. In this case, the detection width is for example measured in a predetermined portion located a few meters after the intersection of the light beams. For this purpose, discrete obstacles can be placed in this predetermined portion and form a barrier, the length of which is then measured as detected by the vehicle, parallel to the front of the vehicle. More simply, when the angular amplitude of the detection field is the same as the angular amplitude of the emitted blue light, then the width of detection is measured by measuring the width of a continuous lighting zone at the front of the vehicle, formed by the set of two light beams, horizontally and parallel to the front of the vehicle, in the predetermined portion.

[0016] Thanks to the invention, the detection width is sufficient when one of the flashing lights is on. In other words, the detection width formed by a single block of the optical units, when one of the two flashing lights is on, is at least equal to the minimum detection width permitted by the two optical units operating simultaneously in detection. For this, the angle formed by the second direction or by the third direction with a direction normal to the front of the vehicle, at least when one of the flashing lights is operating, is greater than in the prior art. This direction normal to the front of the vehicle can be related to an optical axis of the signaling assembly.

[0017] It should be noted that the invention is not limited to emission means comprising light-emitting diodes, if other light sources can be used to implement a device for both signaling and detection.

[0018] In one embodiment of the invention, the first, second, third and fourth directions are not modified when one of the flashing lights is activated. In other words, in this embodiment of the invention, the detection width of each optical unit at a given distance from the vehicle is fixed and much wider than in the prior art.

[0019] In this embodiment of the invention, the emission means of the front left and front right optical units are for example configured so that at a predetermined distance from the vehicle, included in the predetermined portion, the left inner terminal intersects with the right outer terminal, and the right inner terminal intersects with the left outer terminal.

[0020] In other words, the second direction forms an angle to the right with respect to the direction normal to the front face of the vehicle which is greater than an angle formed by the first direction to the left from this normal direction, and the third direction forms an angle to the left with respect to the normal direction which is greater than an angle formed by the fourth direction to the right from this normal direction. The angle formed by the first direction or the fourth direction with respect to the normal direction is for example strictly less than 80 degrees, and is preferably between 30 and 79 degrees, while the angle formed by the second direction or the third direction with respect to the normal direction is greater than or equal to 80 degrees.

[0021] Alternatively in this embodiment of the invention, the third direction is parallel to the first direction, and the second direction is parallel to the fourth direction. The angles formed by each of the first, second, third and fourth directions with respect to the normal direction are equal and of a value for example greater than or equal to 80 degrees in this alternative embodiment.

[0022] Preferably, in this embodiment of the invention where the angular detection field of each optical block is fixed, each first or second light beam is created by refracted light exiting a light guide in which a corresponding incident light is formed by rays of the light signal emitted by the means for emitting the first or respectively second light beam, the light guide comprising at least one output surface and decoupling means at predefined locations of the light guide, the decoupling means being capable of reflecting the rays propagating in the guide to direct them towards said at least one output surface to create the incident light refracting at the output of the light guide.

[0023] The decoupling means are for example prisms aligned on a surface of the light guide opposite said at least one output surface and configured to decouple the rays so as to generate at least said minimum detection width in the predetermined portion. The prisms form patterns whose depth, measured orthogonally to a main extension direction of the light guide, increases from a first end of the light guide proximal to a light source of the emission means of the corresponding optical unit, to a second end of the light guide distal to the first end.These prisms are, for example, triangular-based prisms formed by removing material from the surface of a polycarbonate or PMMA (Polymethyl Methacrylate or Plexiglas ®) guide, the depth of the patterns corresponding to a height of the base of the prism, this height being of the order of 0.1 mm (millimeter) at the first end of the light guide and of the order of 1 mm, or even of the order of 5 mm, at the second end of the light guide.

[0024] In another embodiment of the invention, the left front optical unit comprises means for modifying the angular amplitude of the first light beam when the right front flashing light is activated and the emission means of the right front optical unit are inhibited, and / or the right front optical unit comprises means for modifying the angular amplitude of the second light beam when the left front flashing light is activated and the emission means of the left front optical unit are inhibited. In this other embodiment of the invention, the angular detection field of an optical unit is less wide when none of the flashing lights is on than when the flashing light of the other optical unit is on.

[0025] For example, the means for modifying the angular amplitude of the first light beam are capable of increasing the angle that the second direction makes towards the right by at least 30° relative to the direction normal to the front face of the vehicle and pointing towards the outside. of the vehicle, when the right front flashing light is activated and the emission means of the right front optical unit are inhibited, and the means for modifying the angular amplitude of the second light beam are capable of increasing the angle made by the third direction to the left by at least 30° relative to the normal direction when the left front flashing light is activated and the emission means of the left front optical unit are inhibited. If the angle made by the second direction or the third direction with the normal direction is 30° when the flashing lights are off, then this angle is for example brought to a value greater than or equal to 80° in one of the optical units when the flashing light of the other optical unit is activated.

[0026] In this other embodiment of the invention, the emission means of each optical unit comprise for example at least one deflector, at least a first and a second light source arranged offset from each other on a focal plane object of the deflector, the deflector being configured to transmit rays coming from its focal plane towards the front of the vehicle and thus form the first or second light beam, the modification means of the front left optical unit or respectively of the front right optical unit being capable of supplying the first and / or the second light source of its emission means as a function of the activation of the front right or respectively front left flashing light.

[0027] The first light source is for example arranged on the optical axis of the deflector, while the second light source is horizontally offset from the optical axis while remaining in the focal plane of the deflector. The means for modifying the front left optical unit or respectively the front right optical unit are capable of switching, when the front right or respectively front left flashing light is activated, from the activation of one of the light sources to the other, or from the activation of only one of the light sources to the activation of both light sources.

[0028] Other characteristics and advantages of the invention will become apparent from the following description on the one hand, and from several examples of embodiment given for informational and non-limiting purposes with reference to the attached schematic drawings on the other hand, in which:

[0029] [Fig. 1] schematically represents the operation of an obstacle detection application implemented in signaling assemblies according to the invention,

[0030] [Fig. 2] represents a vehicle equipped with a signaling assembly of Figure 1, and light beams emitted by this signaling assembly when no flashing light is activated, in a first embodiment of the invention,

[0031] [Fig. 3] represents the light beams emitted by the signaling assembly of Figure 2 when a flashing light of this signaling assembly is activated,

[0032] [Fig. 4] represents a vehicle equipped with a signaling assembly of Figure 1, and light beams emitted by this signaling assembly when no flashing light is activated, in a second embodiment of the invention,

[0033] [Fig. 5] represents the light beams emitted by the signaling assembly of Figure 4 when a flashing light of this signaling assembly is activated,

[0034] [Fig. 6] represents a vehicle equipped with a signaling assembly of Figure 1, and light beams emitted by this signaling assembly when no flashing light is activated, in an alternative embodiment of the second embodiment of the invention,

[0035] [Fig. 7] represents the light beams emitted by the signaling assembly of Figure 6 when a flashing light of this signaling assembly is activated,

[0036] [Fig. 8] represents transmission means of an optical block of the signaling assembly of Figure 4 or Figure 6,

[0037] [Fig. 9] represents a front view of transmission means of an optical block of the signaling assembly of figure 2, and

[0038] [Fig. 10] represents a view along their optical axis of the emission means shown in Figure 9.

[0039] Figure 1 represents the operation of an obstacle detection application using a plurality 12 of photonic emitters, which are, in this embodiment of the invention, blue light-emitting diodes adapted to emit white light, for example the light-emitting diodes referenced 121, 122 in Figure 1. These light-emitting diodes are distributed, as shown in Figure 2, in a left front optical unit 22 comprising a left front flashing light, and in a right front optical unit 24 comprising a right front flashing light. These optical units are mounted on the front face of a vehicle 2, and are part of a signaling assembly 1 according to the invention, of the vehicle 2.

[0040] The light-emitting diodes 121, 122 each comprise, for example, a layer of Gallium-Indium Nitride (InGaN) on which a phosphor layer is deposited. Thus, they are suitable for producing a light beam of a positioning light or a daytime running light. In this exemplary implementation of the invention, the light-emitting diodes are used to produce a daytime running light at the output of each optical unit 22, 24. Furthermore, in this exemplary implementation, the output surface of this daytime running light is identical to the output surface of the flashing light in the corresponding optical unit 22, 24. Thus, when the flashing light of an optical unit 22, 24 is activated, the daytime running light of the corresponding optical unit 22, 24 is inhibited, the output surface then being used solely for the flashing light.

[0041] Returning to Figure 1, the optical blocks 22, 24 of the signaling assembly 1 according to the invention also each comprise a plurality 32 of photonic receivers, which are in this embodiment of the invention, photodiodes, for example SPAD (Single-Photon Avalanche Diode) photodiodes for increasing the reception gain, referenced 321, 322. Of course, Figure 1 only comprises two light-emitting diodes and two photodiodes for simplicity, the optical blocks 22, 24 being able to comprise in reality many more diodes and photodiodes.The plurality 12 of light-emitting diodes forms means for emitting a light signal if coded at high frequency towards the outside of the vehicle 2, distributed in each optical block 22, 24 of the signaling assembly 1, and the plurality 32 of photodiodes forms means for receiving such a light signal arriving from the outside of the vehicle 2, distributed in each optical block 22, 24 of the signaling assembly 1.

[0042] The optical blocks 22, 24 are coupled to obstacle detection means 40 implemented at least partly in software in a computer of the vehicle 2. More precisely, the optical blocks 22, 24 of the signaling assembly 1 are connected by a computer bus of the vehicle 2 (shown in dotted lines in Figure 2), for example of the CAN type (from the English "Controller Area Network") to decoding means 38 of the light signals received by the photodiodes 321, 322, these decoding means 38 communicating via the computer bus with the detection means 40.

[0043] We will now describe, in relation to FIG. 1, how the transmission means distributed in each optical block 22, 24 cooperate with the reception means also distributed in each optical block 22, 24.

[0044] The emission means comprise, in addition to the plurality 12 of light-emitting diodes, a source 10 of electrical signals in voltage square waves and an electronic control device 3 of these light-emitting diodes, connected upstream of the plurality 12 of light-emitting diodes. To send the light signal si, the source 10 provides a square wave signal whose width 1 of the square waves is approximately 10ns (nanoseconds), the frequency of the signal being 50MHz. To allow the transmission of this signal having such a high frequency level, the electronic control device 3 comprises for example a pre-equalization stage, possibly associated with an amplifier stage. Instead or in addition, the light-emitting diodes 121, 122 are chosen to be smaller than 300 micrometers so as to naturally have a cut-off frequency greater than 50MHz.

[0045] Furthermore, the electronic control device 3 comprises, in a known manner, a so-called "bias tee" device allowing the injection of a DC voltage into the signal from the signal source 10, possibly amplified, before the application of the sum of this DC voltage and the square wave signal from the signal source 10, to the terminals of the diodes 121, 122. The application of the DC voltage makes it possible to bias the diodes 121, 122, and to allow the emission of the light signal s1 through them. This passes through deflection means 5 before reaching the output surface of an optical unit 22, 24, as will be explained later in relation to FIGS. 8 to 10.

[0046] The reflection of the light signal s on an obstacle 6 gives rise to a reflected light signal s2 of sufficient light power to be captured by the photodiodes 321, 322 of the plurality 32 of photodiodes of the reception means.

[0047] The receiving means comprise, in addition to the photodiodes 321, 322, a blue light filter 8 making it possible to filter the light from the reflected light signal s2 so as to allow only the blue component of this light to pass, and a lens 9 focusing this component towards the photodiodes 321, 322. The blue light emitted by the diodes 121, 122 generally have a light intensity lower than that of the illumination of the sun. However, the light beam emitted by the diodes 121, 122 is modulated so that the analysis of the modulated signals makes it possible to distinguish the reflected light signal s2 (including blue light) from external light pollution in the process of decoding this reflected light signal s2.

[0048] The light signal sent by the diodes 121, 122 encodes a specific sequence of 10 ns wide slots, this sequence repeating cyclically. The sequence of slots is defined so as to easily evaluate a time difference between its transmission and its reception as explained below. For example, it presents three slots which follow one another, then after 60 ns, a single slot, then after 40 ns, two slots which follow one another, etc.

[0049] The emitted light signal s2 hits the obstacle 6 and gives rise to the reflected light signal s2. The photodiodes 321 and 322 capture the blue components of the reflected light signal s2 and of the ambient light, for example sunlight, and provide an electrical signal to an electronic control device 13 which amplifies it and provides it to the decoding means 38. The electronic control device 13 optionally comprises, in addition to an amplifier stage, a post-equalization stage.

[0050] The decoding means 38 comprise a count Nb of the photons received as a function of time t by each of the photodiodes 321, 322, and thresholding means 34 of the intensity of the light signal received by the photodiodes 321, 322 with respect to the light intensity of the sunlight. This thresholding corresponds to a clipping of the counting signal Nb as a function of time t, beyond a number of photons corresponding to the light intensity of the blue component of the sunlight, which gives rise to a thresholded light signal s3. Such thresholding makes it possible to remove from the received electrical signal the component due to sunlight. Of course, what we call a thresholded light signal here is actually an electrical or digital signal corresponding to the thresholding of the received light signal s2.

[0051] The decoding means 38 also comprise means 36 for correlating the thresholded light signal s3 with the light signal si sent by the diodes 121, 122. These correlation means 36 determine a time shift T between the thresholded light signal and the light signal si sent, and transmit this time shift T to the obstacle detection means 40 of the vehicle 2. The obstacle detection means 40 convert this time shift T into a distance relative to an obstacle 6, and therefore make it possible to detect this obstacle.

[0052] It should be noted that the reception means of an optical unit 22, 24 decode reflected light signals s2 corresponding to light signals s1 emitted by one or other of the optical units 22, 24.

[0053] The invention will now be described in more detail, namely in particular the fact that the signaling assembly is configured so that, when a flashing light of an optical unit is activated, the transmission means associated with the other optical unit are configured to cover by themselves a minimum detection width in a predetermined portion of a zone of sharpness of the reception means of the optical units of the vehicle, or more simply at a predetermined distance in front of the vehicle.

[0054] As shown in Figure 2, relating to a first embodiment of the invention, when the emission means of the two optical units 22, 24 operate simultaneously, that is to say when no flashing light is activated, the left front optical unit 22 emits a first light beam 222 extending horizontally relative to the road on which the vehicle 2 is moving, from a first direction dl forming an angle yl of 80 degrees to the left relative to a direction X normal to the front face of the vehicle 2, to a second direction d2 forming an angle y 2 of 30 degrees to the right with respect to this direction X normal to the front face, which here corresponds to an optical axis of the signaling assembly. The first direction d1 forms a left outer terminal of the transmission means of the signaling assembly 1 and the second direction d2 forms a left inner terminal of the transmission means of the signaling assembly 1.

[0055] Similarly, when the emission means of the two optical units 22, 24 operate simultaneously, the right front optical unit 24 emits a second light beam 242 extending horizontally relative to the road on which the vehicle 2 is moving, from a third direction d3 forming a right inner terminal of the emission means of the signaling assembly 1, to a fourth direction d4 forming a right outer terminal of the emission means of the signaling assembly 1. The third direction d3 forms an angle to the left relative to the direction X normal to the front face of the vehicle 2, equal to the angle y 2 of 30 degrees, and the fourth direction d4 forms an angle to the right relative to the direction X normal to the front face of the vehicle 2, equal to the angle yl of 80 degrees.In this configuration, the first light beam 222 and the second light beam 242 intersect at a distance Dl from the front face of the vehicle, this distance Dl being of the order of 1.7 m (meters), the optical units 22 and 24 being spaced 2 m apart on the front face of the vehicle 2.

[0056] At this distance D1, the first and second light beams 222, 242 together form an area at the front of the vehicle, continuously illuminated in the horizontal direction, between the first direction d1 and the fourth direction d4. This area has a dimension, at the predetermined distance D1 of length L, centered on the optical axis OX of the signaling assembly 1 and measured horizontally and parallel to the front face of the vehicle 2. This length L corresponds to a light emission width, formed by the first and second light beams 222 and 242, and measured at the predetermined distance D1. It can also be said that it corresponds to an angular amplitude of [-80 degrees; +80 degrees] relative to the optical axis OX of the signaling assembly 1.

[0057] For simplicity, it is considered in the following description that this light emission width L corresponds to a detection width L, that is to say that thanks to the emission means 12, the reception means 32 and the obstacle detection means 40, the vehicle 2 can detect any obstacle located between the first and second directions beyond the predetermined distance D1. In reality, the detection width L may be smaller than the light emission width because the reception means 32 are not necessarily configured to receive any reflected light signal s2 of a direction between the first direction and the fourth direction. However, it is assumed here that the detection width L is equal to the width of the beams 222, 242 at their intersection, and that this detection width L is greater than a minimum detection width LO, necessary for safe obstacle detection in front of the vehicle.This minimum detection width is, for example, two meters. Of course, the further one moves away from the vehicle in the sharpness zone, the larger this detection width becomes. The minimum detection width is therefore smaller the closer it is to the vehicle. The predetermined distance D1 forms, in this embodiment, a lower limit of a predetermined portion of a sharpness zone of the receiving means 32.

[0058] Figure 3 shows a configuration in which the flashing light of an optical unit, here the right front optical unit, is activated, and therefore in which only the emission means of the other optical unit, here the left front optical unit 22, operate. In order to preserve the minimum detection width LO at the predetermined distance D1, in this configuration the first beam 222 extends from the first direction d1, forming the angle yl of 80 degrees to the left with respect to the direction X, to the second direction d2 whose angle with the direction X is increased with respect to the previous configuration. in effect the second direction d2 now forms with the direction X, an angle y 3 to the right, greater than 80 degrees, for example 90 degrees. As a result, the second direction d2 intersects with the fourth direction d4 at a distance D2 in front of the vehicle, this distance D2 also being included in the sharpness zone of the reception means 32 of the optical units 22, 24. This allows sufficient detection over a significant distance in front of the vehicle. The predetermined distance D2 forms an upper limit of a predetermined portion of the sharpness zone of the reception means 32. Thus any measurement of detection width carried out in the predetermined portion must make it possible to verify that the detection width in this predetermined portion is greater than the minimum detection width LO.

[0059] The angular amplitude of the first beam 222 therefore corresponds to [-80 degrees; +90 degrees] relative to the optical axis OX of the signaling assembly 1, which makes it possible to preserve the minimum detection width LO of the previous configuration.

[0060] As a variant of this first embodiment, when the flashing light, here in the right optical unit, is activated, compared to the configuration of FIG. 2, the angle yl that the first direction d1 makes to the left relative to the direction X can be reduced while the angle that the second direction d2 makes to the right relative to the direction X can be increased. It is thus possible to obtain, for example, an angular amplitude of the first beam 222 of [-30 degrees; + 80 degrees] relative to the optical axis of the front left optical unit 22, which may be sufficient to preserve an illuminated zone at the front of the vehicle, one dimension of which is of minimum length the minimum detection width L0, measured in the horizontal direction, between the first direction d1 and the second direction d2, at the predetermined distance D1.In this embodiment of the invention, it is especially important that the interior angle y 3 is greater than the exterior angle yl to obtain the intersection of the second d2 and fourth directions d4 in the sharpness zone.

[0061] Of course, when the left flashing light is activated, the second light beam 242 emitted by the right front optical unit 24 is symmetrical to the first light beam 222 emitted by the left front optical unit 22 when the right flashing light is activated, relative to the optical axis OX of the signaling assembly 1.

[0062] Finally, in this first embodiment of the invention, it is important to increase the angle made by the light beam 222, 242 emitted by one of the optical units 22, 24 when the other of the optical units 24, 22 is inhibited, relative to the normal direction X to the front face of the vehicle 2, and relative to a configuration where the two optical units 22, 24 operate together.

[0063] According to a second embodiment shown in Figures 4 to 5, the emission means of the two optical units 22, 24 are configured to form respectively a first light beam 222a and a second light beam 242a, these beams being identical whether one of the flashing lights of the vehicle is activated or not.

[0064] The first light beam 222a extends horizontally relative to the road on which the vehicle 2 is moving, from the first direction dl forming an angle yl of 80 degrees to the left relative to the direction X normal to the front face of the vehicle 2, to the second direction d2 forming an angle y 3 of 90 degrees to the right relative to the direction X normal to the front face of the vehicle 2.

[0065] The second light beam 242a extends horizontally relative to the road on which the vehicle 2 is moving, from the third direction d3 forming an angle y 3 of 90 degrees to the left relative to the direction X normal to the front face of the vehicle 2, to the fourth direction d4 forming an angle yl of 80 degrees to the right relative to the direction X normal to the front face of the vehicle 2.

[0066] In this second embodiment of the invention, the minimum detection width L0 is for example 50cm and is measured at a predetermined distance Dl taken as the hyperfocal distance of the receiving means 32, divided by two. The predetermined distance DI is for example 40 cm and forms a lower limit of the predetermined portion of the sharpness zone of the receiving means 32. The distance D2, corresponding to the distance at which the second direction d2 and fourth direction d4 intersect, forms an upper limit of the predetermined portion of the sharpness zone of the receiving means 32.

[0067] Alternatively, the upper limit of the predetermined portion corresponds to the last clear plane permitted by the reception means of the right or left front optical units. In other words, in this variant the predetermined portion extends over the depth of field of the optical reception system.

[0068] At the predetermined distance D1, the first and second light beams 222a, 242a make it possible to obtain an illuminated zone at the front of the vehicle whose dimension, measured horizontally and parallel to the front face of the vehicle 2, is equal to the length L, greater than the minimum detection width LO. The configuration of the optical units 22, 24, operating together in this second embodiment, therefore makes it possible to have at least the same angular detection amplitude as in the configuration of FIG. 2.

[0069] Figure 5 shows a configuration in which the flashing light of one of the optical units, here the right front optical unit 24, is activated, and therefore in which only the emission means of one optical unit, here the left front optical unit 22, operate, in this second embodiment of the invention. The first beam 222a being identical to that of the previous configuration, the illuminated zone at the front of the vehicle has, horizontally and parallel to the front face of the vehicle, a length dimension equal to the minimum detection width LO at the predetermined distance D1. This configuration is made possible in particular by the fact that the angle y3 formed by the second direction d2 to the right relative to the normal direction X, is greater than the angle yl formed by the first direction dl to the left with respect to the normal direction X, and by the choice of these two angles yl and y3. The angle yl being generally 80 degrees, this means that the angle y 3 is greater than or equal to 80 degrees.

[0070] Of course, when the left flashing light is activated, the second light beam 242a emitted by the right front optical unit 24 is symmetrical to the first light beam 222a emitted by the left front optical unit 22 when the right flashing light is activated, relative to the optical axis OX of the signaling assembly 1.

[0071] According to an alternative embodiment of this second embodiment shown in FIG. 6, the emission means of the two optical units 22, 24 are configured to form respectively a first light beam 222b and a second light beam 242b, these beams being identical whether one of the flashing lights of the vehicle is activated or not.

[0072] In this variant, the first light beam 222b extends horizontally relative to the road on which the vehicle 2 is moving, from the first direction dl forming an angle yl of 80 degrees to the left relative to the direction X normal to the front face of the vehicle 2, to the second direction d2 also forming an angle yl of 80 degrees to the right relative to the direction X normal to the front face of the vehicle 2.

[0073] Similarly, the second light beam 242b extends horizontally relative to the road on which the vehicle 2 is moving, from the third direction d3 forming an angle yl of 80 degrees to the left relative to the direction X normal to the front face of the vehicle 2, to the fourth direction d4 also forming an angle yl of 80 degrees to the right relative to the direction X normal to the front face of the vehicle 2.

[0074] This configuration also makes it possible to obtain, at the predetermined distance Dl, for example equal to the divided hyperfocal distance by two, or greater than this distance but included in the sharpness zone of the reception means 32, an illuminated zone at the front of the vehicle whose dimension, measured horizontally and parallel to the front face of the vehicle 2, is equal to a length L greater than the minimum detection width LO. The configuration of the optical blocks 22, 24 operating together in this variant of the second embodiment therefore makes it possible to have at least the same angular amplitude of detection as in the configuration of FIG. 2.

[0075] Figure 7 shows a configuration in which the flashing light of the left front optical unit 22 is activated, and therefore in which only the emission means of the right front optical unit 24 operate, in this variant embodiment of the invention. The second beam 242b being identical to that of the previous configuration, the illuminated zone at the front of the vehicle has, horizontally and parallel to the front face of the vehicle, a length dimension equal to the minimum detection width LO, at the predetermined distance D1.

[0076] This variant embodiment shows the possibility of carrying out the invention with beams symmetrical with respect to the normal direction X to the front face of the vehicle, provided that the angle of each beam with respect to this normal direction X is sufficiently large.

[0077] 11 It should be noted that in Figures 2 to 7, for visibility reasons the angles represented do not have values ​​of 80 degrees or more, but have smaller values, which in particular distorts the perception of the dimension of the illuminated area at the front of the vehicle, which is in reality much wider horizontally and parallel to the front of the vehicle. This means that in reality, in the configurations without activated flashing light and with activated flashing light, the dimension of the minimum detection width LO representative of the angular detection amplitude is always almost centered or centered on the optical axis OX of the vehicle.

[0078] The angular amplitude of detection being in reality smaller than the angular amplitude of emission, the invention makes it possible to maintain, at the predetermined distance D1, the same amplitude of detection in each of the configurations, that is to say whether a flashing light is activated or not.

[0079] Figure 8 illustrates the operation of emission means of the optical blocks 22, 24 in the second embodiment of the invention. These emission means comprise a light guide 7, for example made of polycarbonate or Polymethyl Methacrylate (PMMA). This light guide 7 is worked on a first surface 71 along its length, so as to form on this first surface 71, by removal of material, prisms with triangular bases 7_1 to 7_n. The height of each prism 7_1 to 7_n is oriented parallel to the first surface 71 and orthogonally to the length of the light guide 7, so that a light ray passing through the fiber is likely to be reflected on a lateral surface of one of the prisms, or to pass through at least one lateral surface of one of the prisms. The volume of each prism 7_1 to 7_n is made of air.

[0080] The light guide 7 is capable of receiving the light signal s i emitted by the plurality 12 of light-emitting diodes, this light signal propagating by reflection in the light guide 7, and exiting the light guide 7 by refraction through a second surface 72, which is an exit surface opposite the first surface 71. More precisely, when a light ray arrives on a surface of the light guide 7 with an angle of incidence less than 40 degrees, then it is refracted, while when it arrives on a surface of the light guide 7 with an angle of incidence greater than 40 degrees, then it is reflected.

[0081] Thus, the light ray sl_l of the light signal si arriving in the light guide on the prism 7_1 with an angle of incidence greater than 40 degrees is reflected on the surface of the prism 7_1 and leaves towards the exit surface 72 with an angle of incidence pi less than 40 degrees. As a result, the light ray sl_l exits the light guide 7 and participates in forming one of the lighting beams 222a, 242a, or 222b, 242b.

[0082] Another light ray sl_2 of the light signal si arriving in the light guide on the prism 7_1 with an angle of incidence less than 40 degrees, passes through the prism 7_1 and leaves it forming on a surface of the following prism 7_2, an angle of incidence greater than 40 degrees. As a result, the light ray sl_2 is reflected on this surface of the prism sl_2 and leaves towards the exit surface 72 with an angle of incidence 2 less than 40 degrees. It therefore leaves the exit surface 72 and participates in forming one of the lighting beams 222a, 242a, or 222b, 242b.

[0083] As the light passes along the light guide 7, the corresponding light rays exit the output surface 72 having passed through more and more prisms and with angles of incidence pi, p2 ... pn covering the range [-40°; 40°] relative to the normal to the output surface 72, which makes it possible to obtain one of the light beams 222a, 242a, 222b, 242b.

[0084] For this, the prisms 7_1...7_n have a surface to the incident rays coming from the plurality 12 of light-emitting diodes, making an angle a1, a2...an with the first surface 71, which becomes larger and larger as one moves away from the plurality 12 of light-emitting diodes. In addition, the depth of each prism 7_1, ... 7_n, orthogonal to the length of the light guide 7, increases the further one moves away from the plurality 12 of light-emitting diodes. In particular, the height of the base of the first prism 7_1 is between 0.05mm and 0.2mm, for example is 0.1mm, and the height of the base of the last prism 7_n is between 0.8mm and 2mm, and is for example 1mm.

[0085] Figures 9 and 10 illustrate the operation of emission means of the optical blocks 22, 24 in the first embodiment of the invention. In this first embodiment of the invention, the emitting means of the optical blocks 22, 24 comprise means for modifying the angular amplitude of one of the light beams 222, 242 when the other of the light beams 242, 222 is inhibited. These modification means use the deflector 5 (also referenced figure 1) of focus F, for example a lens, as well as an offset of the light sources present in the plurality 12 of light-emitting diodes relative to an optical axis FX of the deflector 5.

[0086] In particular, the plurality 12 of light-emitting diodes may comprise a single light-emitting diode with several light-emitting chips, for example six chips as shown in FIG. 9.

[0087] Four of these six chips form an assembly 12a, capable of producing the light beam 222 or 242 as described in relation to FIG. 2, when no flashing light is on. For this, the chips of the assembly 12a are distributed in the focal plane of the deflector 5 so that the rays that they emit form the beam 222 or 242 with the optical axis FX. In particular, the rays emitted by the assembly 12a form a maximum angle yl on a first side of the optical axis FX, measured horizontally relative to the road, and a maximum angle y 2 on a second side of the optical axis FX distinct from the first side, the maximum angle y 2 being measured horizontally relative to the road.

[0088] Two more of the six chips form an assembly 12b. When both the chips of assembly 12a and the chips of assembly 12b emit light, the assemblies 12a and 12b jointly produce the light beam 222 or 242 as described in relation to FIG. 3, when a flashing light is switched on. For this, the assembly 12b is horizontally offset relative to the optical axis FX of the deflector 5, while remaining in the focal surface of the deflector 5. The positions of the chips of assembly 12b are such that these chips emit rays forming a minimum angle y 2 on the second side of the optical axis FX, in a horizontal direction relative to the road, and a maximum angle y 3 on the second side of the optical axis FX, in a horizontal direction relative to the road.

[0089] Alternatively, the chip sets 12a and 12b are replaced by separate light-emitting diodes or sets of separate light-emitting diodes.

[0090] Of course, the invention is not limited to the examples which have just been described and numerous adjustments can be made to these examples without departing from the scope of the invention.

Claims

CLAIMS

1. Signaling assembly (1) for a vehicle (2), comprising a left front optical unit (22) comprising a left front flashing light and a right front optical unit (24) comprising a right front flashing light, each optical unit (22, 24) further comprising means (12, 7, 5) for transmitting a high-frequency coded light signal (s1) to the outside of the vehicle (2), and means (32) for receiving such a light signal (s2) arriving from outside the vehicle (2), the receiving means (32) comprising means for coupling to obstacle detection means (40) of the vehicle (2), the transmitting means (12, 7, 5) of the left front optical unit (22) being configured, when no flashing light is activated, to generate a first light beam (222, 222a, 222b) extending between a first direction (d1) forming a left outer terminal and a second direction (d2) forming a left outer terminal and a second direction (d3) forming a left outer terminal. direction (d2) forming a left inner terminal, the transmission means (12, 7,5) of the right front optical unit (24) being configured, when no flashing light is activated, to generate a second light beam (242, 242a, 242b) extending between a third direction (d3) forming a right inner terminal and a fourth direction (d4) forming a right outer terminal, the emission means (12, 7, 5) of the left front optical unit (22) and the emission means (12, 7, 5) of the right front optical unit (24) being capable of:, - on the one hand to cover together a detection field having a detection width between the first direction (dl) and the fourth direction (d4) in a predetermined portion of a sharpness zone of the reception means of the optical units, greater than or equal to a minimum detection width, the detection width being measured parallel to a front face of the vehicle, and - on the other hand to ensure a daytime running light and / or positioning function, the signaling assembly (1) being characterized in that that, at least when the left flashing light is activated, the emission means (12, 7, 5) of the right front optical unit (24) are configured to cover by themselves the minimum detection width (LO) in the predetermined portion, and, at least when the right flashing light is activated, the emission means (12, 7, 5) of the left optical unit (22) are configured to cover by themselves the minimum detection width (LO) in the predetermined portion.

2. Signaling assembly (1) according to claim 1, in which the first, second, third and fourth directions (d1, d2, d3, d4) are not modified during activation of one of the flashing lights.

3. Signaling assembly (1) according to claim 2, wherein the emission means (12, 7) of the front left (22) and front right (24) optical units are configured so that at a predetermined distance (D2) from the vehicle (2), included in the predetermined portion, the left inner terminal intersects with the right outer terminal, and the right inner terminal intersects with the left outer terminal.

4. Signaling assembly (1) according to claim 2, wherein the second direction (d2) forms an angle (y3) to the right with respect to a normal direction (X) to the front face of the vehicle (2) which is greater than an angle (yl) formed by the first direction (dl) to the left from this normal direction (X), and wherein the third direction (d3) forms an angle (y3) to the left with respect to the normal direction (X) which is greater than an angle (yl) formed by the fourth direction (d4) to the right from this normal direction (X).

5. Signaling assembly (1) according to claim 2, wherein the third direction (d3) is parallel to the first direction (d1), and wherein the second direction (d2) is parallel to the fourth direction (d4).

6. Signaling assembly (1) according to any one of claims 2 to 5, wherein each first or second light beam (222a, 222b, 242a, 242b) is created by refracted light exiting a light guide (7) in which a corresponding incident light is formed by rays of the light signal (si) emitted by the emission means (12, 7) of the first or respectively second light beam (222a, 222b, 242a, 242b), the light guide (7) comprising at least one exit surface (72) and decoupling means (7_l,...,7_n) at predefined locations of the light guide (7), the decoupling means (7_l,...,7_n) being capable of reflecting the rays propagating in the light guide (7) to direct them towards said at least one exit surface (72) to create the light incident refracting at the exit of the light guide (7).

7. Signaling assembly (1) according to the preceding claim, in which the decoupling means (7_1, ..., 7_n) are prisms aligned on a surface (71) of the light guide opposite said at least one output surface (72) and configured to decouple the rays so as to generate at least said minimum detection width (LO) in the predetermined portion.

8. Signaling assembly (1) according to the preceding claim, in which the prisms (7_l,...,7_n) form patterns whose depth, measured orthogonally to a main direction of extension of the light guide, increases from a first end of the light guide proximal to a light source (12) of the emission means (12, 7) of the corresponding optical block (22, 24), to a second end of the light guide distal to the first end.

9. Signaling assembly (1) according to claim 1, in which the left front optical unit (22) comprises means for modifying the angular amplitude of the first light beam (222) when the right front flashing light is activated and the emission means (12, 5) of the right front optical unit (24) are inhibited, and in in which the right front optical unit (24) comprises means for modifying the angular amplitude of the second light beam (242) when the left front flashing light is activated and the emission means (12, 5) of the left front optical unit (22) are inhibited.

10. Signaling assembly (1) according to the preceding claim, wherein the means for modifying the angular amplitude of the first light beam (222) are capable of increasing the angle that the second direction (d2) makes to the right by at least 30° relative to a normal direction (X) to the front face of the vehicle (2) and pointing towards the outside of the vehicle (2), when the right front flashing light is activated and the emission means (12, 5) of the right front optical unit (24) are inhibited, and wherein the means for modifying the angular amplitude of the second light beam (242) are capable of increasing the angle that the third direction (d3) makes to the left by at least 30° relative to the normal direction (X) when the left front flashing light is activated and the emission means (12, 5) of the left front optical unit (22) are inhibited.

11. Signaling assembly (1) according to one of claims 9 or 10, wherein the emission means (12, 5) of each optical unit (22, 24) comprise at least one deflector (5), at least a first and a second light source (12a, 12b) arranged offset from each other on a focal plane object of the deflector (5), the deflector (5) being configured to transmit rays coming from its focal plane towards the front of the vehicle (2) and thus form the first or second light beam (222, 242), the modification means of the front left optical unit (22) or respectively of the front right optical unit (24) being capable of supplying the first and / or the second light source (12a, 12b) of its emission means (12, 5) as a function of the activation of the front right or front left flashing light respectively.

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