Vehicle signal assembly for obstacle detection

Abstract

The invention relates to a signal assembly (1) for a vehicle (2), the signal assembly comprising a left front optical unit (22) and a right front optical unit (24), both of which are capable of covering a detection field having an angular amplitude (L) extending between a first direction (d1) and a fourth direction (d4). The left front optical unit (22) is configured to generate a first light beam (222) that covers the angular amplitude (L) of the detection field by itself when the turn signal is not activated, and the right front optical unit (24) is configured to generate a second light beam (242) that covers the angular amplitude (L) of the detection field by itself when the turn signal is not activated.

Description

Technical Field

[0001] The present invention relates to the fields of automobiles and optical systems. More specifically, it relates to a signal assembly for a vehicle.

Summary of the Invention

[0002] In recent vehicles, light-emitting diode assemblies are commonly used to generate external lighting devices such as direction indicator lights. These diode assemblies make it possible to save energy and give the vehicle a light emission signature unique to each brand, and are considered a future means for communicating between vehicles or with road infrastructure using optical communication technologies such as VLC (Visible Light Communication).

[0003] This is because the bandwidth of a conventional light-emitting diode with a side length of 1 millimeter is about 5 MHz (megahertz), which is sufficient to enable light emission communication between vehicles or between a vehicle and road infrastructure. However, this bandwidth is not suitable for obstacle detection applications. Such applications are generally optically implemented in some vehicles using LiDAR (Light Detection And Ranging) technology based on a laser sensor for analyzing reflected signals over a bandwidth on the order of several tens of megahertz or several hundreds of megahertz. However, vehicle-mounted LiDAR systems are very expensive.

[0004] However, the inventors have found that such obstacle detection applications are possible using light-emitting diodes by increasing their bandwidths by means of equalization techniques, or by using diodes less than 300 micrometers, or by combining these techniques. This application may require the use of certain types of control units such as a high-speed control unit or a laser control unit. Furthermore, the light-emitting diodes used for this application are blue light-emitting diodes adapted to emit white light.

[0005] This discovery has enabled the inventors to replace expensive LiDAR technology in vehicles with a specific signaling device based on light-emitting diodes that performs obstacle detection functions in addition to regulatory signaling functions.

[0006] Now, in order to enable vehicles to maintain the same light signature under different driving conditions, turn signals, daytime running lights, and / or position lights very often share the same emission surface within the same optical unit of a vehicle. In this context, regulatory standards mean that when a vehicle driver activates a turn signal, daytime running lights or position lights that share the same emission surface as the turn signal will automatically turn off so as not to interfere with the perception of the turn signal by other road users.

[0007] This means that if an obstacle detection application designed by the inventor is integrated into this optical unit, when the turn signal is activated, the blue light-emitting diode used by that application will not function and therefore will not contribute to obstacle detection performed collectively by the vehicle's optical unit. More specifically, the obstacle detection application relies solely on the light emitted by the blue light-emitting diode of that optical unit when the turn signal of that optical unit is not activated, which limits the obstacle detection area of ​​the vehicle. In particular, when the right turn signal is activated, some obstacles close to the right side of the vehicle will not be detected, and conversely, when the left turn signal is activated, some obstacles close to the left side of the vehicle will not be detected.

[0008] The present invention aims to overcome at least some of the aforementioned drawbacks by providing a signal assembly for a vehicle, wherein the optical unit has the same emission surface with respect to turn signal signals and position lights or daytime running lights, and the signal assembly maintains a sufficient obstacle detection area when one of the turn signal signals is activated.

[0009] To that end, the invention proposes a signal assembly for a vehicle, the signal assembly comprising a front left optical unit having a front left turn signal signal and a front right optical unit having a front right turn signal, each optical unit further comprising an emitting means for emitting a high-frequency encoded light-emitting signal to the outside of the vehicle and a receiving means for receiving such light-emitting signals arriving from the outside of the vehicle, the receiving means comprising means for connecting to the vehicle's obstacle detection means, The emission means of the forward left optical unit is configured to generate a first light beam extending between a first direction forming the left outer boundary and a second direction forming the left inner boundary when the direction indicator signal is not activated. The emission means of the forward right optical unit is configured to generate a second light beam extending between a third direction forming the right inner boundary and a fourth direction forming the right outer boundary when the direction indicator signal is not activated. The ejection means for the front left optical unit and the ejection means for the front right optical unit are capable of performing the following: - Firstly, in a predetermined portion of the sharpening zone of the receiving means of the optical unit, the detection field has a detection width between the first direction and the fourth direction, and covers both detection fields that are greater than or equal to the minimum detection width, and the detection width is measured parallel to the front of the vehicle, - Secondly, the signal assembly provides daytime running light functionality and / or position light functionality, wherein the emission means of the front right optical unit is configured to cover a minimum detection width in a predetermined portion by itself when at least the left turn signal is activated, and the emission means of the front left optical unit is configured to cover a minimum detection width in a predetermined portion by itself when at least the right turn signal is activated.

[0010] The sharpness zone is located between, on the one hand, the sharpness plane that can be formed closest to the front of the vehicle in the image captured by the receiving means of the front right or left optical unit, and on the other hand, the sharpness plane that can be formed furthest from the front of the vehicle in the image captured by the receiving means of the front right or left optical unit. The distance between these two planes corresponds to the depth of field of the receiving means of the front right or left optical unit.

[0011] In the signaling system according to the invention, position lights or daytime running lights are not permitted to operate simultaneously with turn signal lights because their emission surfaces coincide or are too close to each other.

[0012] When the turn signal is not activated (i.e., not illuminated), the emitting means of the optical unit both cover the light-emitting field from the first direction to the fourth direction. Therefore, the corresponding detection width is contained between these first and fourth directions and extends roughly between these two directions, depending on the distance from the vehicle and the arrangement of the receiving means of the optical unit.

[0013] The detection width is measured parallel to the road and the front of the vehicle in the sharp zone of the receiving means, and a predetermined portion is defined, for example, between a first predetermined distance in front of the vehicle and a second predetermined distance in front of the vehicle that is further than the first predetermined distance from the vehicle. The detection width in this predetermined portion must always be greater than the minimum detection width, and the minimum detection width must be large enough to allow the detection of obstacles in front of the vehicle at a sufficiently close distance.

[0014] For example, the predetermined portion begins at a position obtained by dividing the hyperfocal distance of the receiving means by 2. This predetermined portion has a depth of, for example, 50 centimeters (cm) in a direction perpendicular to the front of the vehicle. Therefore, any measurement of the detection width of the emission means of the front right or left optical unit after the hyperfocal distance of the receiving means is obtained by dividing by 2 must be greater than, for example, a minimum detection width of 50 cm in this predetermined portion.

[0015] In another example, when the first and second light beams are operating together, the minimum detection width at the point of intersection is 2 meters (m) or more. In this case, the detection width is measured, for example, in a predetermined section located several meters after the intersection of the light beams. This can be achieved by placing discrete obstacles in this predetermined section to form a barrier, and the length of this barrier detected by the vehicle is then measured parallel to the front of the vehicle. More simply, if the angular amplitude of the detection field matches the angular amplitude of the emitted blue light, the detection width is measured in a predetermined section by measuring the width of the continuous illuminated area in front of the vehicle, collectively formed by the two light beams, in a direction parallel and horizontal to the front of the vehicle.

[0016] The invention ensures that the detection width is sufficient when one of the turn signal signals is switched on. In other words, when one of the two turn signal signals is switched on, the detection width formed by a single unit of the optical unit is at least equal to the minimum detection width allowed by two optical units operating simultaneously for detection purposes. This is achieved by the fact that, when at least one of the turn signal signals is activated, the angle formed by the second or third direction along with the normal direction to the front of the vehicle is greater than in the prior art. This normal direction to the front of the vehicle can be associated with the optical axis of the signal assembly.

[0017] It should be noted that the invention is not limited to emission means including light-emitting diodes if other light sources are available to implement both signaling and detection devices.

[0018] In one embodiment of the invention, the first, second, third, and fourth directions are not changed when one of the turn signal signals 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 optical unit and the front right optical unit are configured such that, for example, at a predetermined distance from a vehicle included in a predetermined portion, the left inner boundary intersects the right outer boundary, and the right inner boundary intersects the left outer boundary.

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

[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. In this alternative embodiment, the angles formed by the first, second, third, and fourth directions with respect to the normal direction are equal and have a value of, for example, 80 degrees or more.

[0022] Preferably, in this embodiment of the invention, where the angle detection field of each optical unit is fixed, each of the first or second light beams is generated by refracted light emanating from a light guide, in which the corresponding incident light is formed by a ray of a light emission signal emitted by an emission means for emitting the first or second light beam, the light guide having at least one emission surface and a decoupling means at a predetermined point of the light guide, the decoupling means capable of reflecting rays propagating through the light guide to direct them toward the at least one emission surface so as to generate incident light that is refracted at the exit of the light guide.

[0023] The decoupling means is, for example, a prism aligned on the surface of the light guide opposite to the at least one emission surface, and is configured to decouple the light rays to generate at least the minimum detection width in a given portion. These prisms form a pattern having a depth measured perpendicular to the main direction of extension of the light guide, the depth increasing from a first end of the light guide close to the light source of the emission means of the corresponding optical unit to a second end of the light guide spaced away from 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 plexiglass®) guide, the depth of the pattern corresponds to the height of the base of the prism, which is on the order of about 0.1 mm (millimeters) at the first end of the light guide, on the order of about 1 mm at the second end of the light guide, or even on the order of about 5 mm.

[0024] In another embodiment of the invention, the front left optical unit includes means for changing the angular amplitude of a first light beam when the front right turn signal is activated and the emission means of the front right optical unit is suppressed, and / or the front right optical unit includes means for changing the angular amplitude of a second light beam when the front left turn signal is activated and the emission means of the front left optical unit is suppressed. In this other embodiment of the invention, the angle detection field of one optical unit when neither turn signal is switched on is narrower than when the turn signal of the other optical unit is switched on.

[0025] For example, the means for changing the angular amplitude of the first light beam can increase the angle formed by the second direction, which is directed towards the outside of the vehicle, by at least 30° to the right with respect to the normal direction to the front surface of the vehicle when the front right direction indicator signal is activated and the emission means of the front right optical unit are suppressed. The means for changing the angular amplitude of the second light beam can increase the angle formed by the third direction by at least 30° to the left with respect to the normal direction when the front left direction indicator signal is activated and the emission means of the front left optical unit are suppressed. When the direction indicator signal is switched off and the angle formed by the second or third direction together with the normal direction is 30°, this angle is set to a value of 80° or more in one of the optical units, for example, when the direction indicator signal of the other optical unit is activated.

[0026] In this further embodiment of the invention, the emission means of each optical unit includes, for example, at least one deflector and at least first and second light sources arranged offset from each other on the object focal plane of the deflector. The deflector is configured to transmit the light rays derived from its focal plane forward of the vehicle, thereby forming the first or second light beam. The means for changing the front left optical unit or the front right optical unit can supply power to the first and / or second light sources of its emission means, respectively, in response to the activation of the front right or front left direction indicator signal.

[0027] The first light source is arranged, for example, on the optical axis of the deflector. On the other hand, the second light source remains within the focal plane of the deflector and is offset horizontally from the optical axis. The means for changing the front left optical unit or the front right optical unit can switch from the operation of one light source to the other or switch from the operation of only one light source to the operation of both light sources when the front right or front left direction indicator signal is activated.

[0028] Other features and advantages of the invention will become clearer from the following description on the one hand and from the examples of a plurality of embodiments given non - limitatively and by way of illustration with reference to the accompanying schematic drawings on the other hand.

Brief Description of the Drawings

[0029] [Figure 1] FIG. 1 schematically shows the operation of an obstacle detection application implemented in a signal assembly according to the invention. [Figure 2] FIG. 2 shows a vehicle equipped with the signal assembly of FIG. 1 and the light beam emitted by this signal assembly when no direction indicator signal is activated in the first embodiment of the invention. [Figure 3] FIG. 3 shows the light beam emitted by the signal assembly of FIG. 2 when the direction indicator signal of this signal assembly is activated. [Figure 4] FIG. 4 shows a vehicle equipped with the signal assembly of FIG. 1 and the light beam emitted by this signal assembly when no direction indicator signal is activated in the second embodiment of the invention. [Figure 5] FIG. 5 shows the light beam emitted by the signal assembly of FIG. 4 when the direction indicator signal of this signal assembly is activated. [Figure 6] FIG. 6 shows a vehicle equipped with the signal assembly of FIG. 1 and the light beam emitted by this signal assembly when no direction indicator signal is activated in a modified embodiment of the second embodiment of the invention. [Figure 7] FIG. 7 shows the light beam emitted by the signal assembly of FIG. 6 when the direction indicator signal of this signal assembly is activated. [Figure 8] FIG. 8 shows the emission means of the optical unit of the signal assembly of FIG. 4 or FIG. 6. [Figure 9] FIG. 9 shows a front view of the emission means of the optical unit of the signal assembly of FIG. 2. [Figure 10] FIG. 10 shows a view of the emission means shown in FIG. 9 along their optical axes. [Modes for carrying out the invention]

[0030] Figure 1 illustrates the operation of an obstacle detection application using multiple photonic emitters 12, which in this embodiment of the invention are blue light-emitting diodes capable of emitting white light, such as the light-emitting diodes reference numeral 121 and 122 in Figure 1. These light-emitting diodes are distributed in a front left optical unit 22, which includes a front left turn signal, and in a front right optical unit 24, which includes a front right turn signal, as shown in Figure 2. These optical units are mounted on the front of the vehicle 2 and form part of the signal assembly 1 according to the invention of the vehicle 2.

[0031] Each of the light-emitting diodes 121 and 122 includes, for example, a layer of indium gallium nitride (InGaN), on which a phosphor layer is deposited. Therefore, they are capable of generating a light beam for position lights or daytime running lights. In this embodiment of the invention, the light-emitting diodes are used to generate daytime running lights at the output of each optical unit 22, 24. Furthermore, in this embodiment, the emission surface of the daytime running lights is identical to the emission surface of the turn signal in the corresponding optical units 22, 24. Therefore, when the turn signal of the optical units 22, 24 is activated, the daytime running lights of the corresponding optical units 22, 24 are suppressed, and their emission surfaces are subsequently used only for the turn signal.

[0032] Returning to Figure 1, the optical units 22 and 24 of the signal assembly 1 according to the invention each also include a plurality of photonic receivers 32, which in this embodiment of the invention are photodiodes, for example, SPAD (single-photon avalanche diode) photodiodes for increasing the receiving gain, and are referred to as reference numerals 321 and 322. Of course, for the sake of simplification, Figure 1 only has two light-emitting diodes and two photodiodes, and the optical units 22 and 24 can actually include more diodes and photodiodes. The plurality of light-emitting diodes 12 form an emission means for emitting a high-frequency encoded light-emitting signal s1 to the outside of the vehicle 2, and they are distributed in each optical unit 22 and 24 of the signal assembly 1, and the plurality of photodiodes 32 form a receiving means for receiving this type of light-emitting signal coming from outside the vehicle 2, and they are distributed in each optical unit 22 and 24 of the signal assembly 1.

[0033] The optical units 22 and 24 are connected to obstacle detection means 40, which are at least partially implemented as software in the computer of the vehicle 2. More specifically, the optical units 22 and 24 of the signal assembly 1 are connected by the computer bus of the vehicle 2 (shown by dashed lines in Figure 2), for example by a CAN (Controller Area Network) type computer bus, to decoding means 38 for decoding light emission signals received by photodiodes 321 and 322, which in turn communicate with detection means 40 via the computer bus.

[0034] The following explanation, with reference to Figure 1, describes how the emission means distributed in each optical unit 22, 24 cooperate with the receiving means also distributed in each optical unit 22, 24.

[0035] In addition to the multiple light-emitting diodes 12, the emission means includes a source 10 of a square wave voltage electrical signal and an electronic control unit 3 for controlling these light-emitting diodes, which are connected upstream of the multiple light-emitting diodes 12. To transmit the light-emitting signal s1, the source 10 provides a pulsed square wave signal having a width l of about 10 ns (nanoseconds), and the frequency of the signal is 50 MHz. To enable this signal having such a high frequency level to be transmitted, the electronic control unit 3 includes, for example, a pre-equalization stage, optionally associated with an amplification stage. Alternatively, or in addition to this, the light-emitting diodes 121, 122 are selected to be less than 300 micrometers in diameter so that they naturally have a cutoff frequency above 50 MHz.

[0036] Furthermore, the electronic control unit 3 includes a “bias tee” device that enables the injection of a DC voltage into a signal derived from the signal source 10 and optionally amplified in a known manner, which is done before the sum of the DC voltage and the square wave signal derived from the signal source 10 is applied to the terminals of diodes 121 and 122. By applying the DC voltage, the diodes 121 and 122 are biased, thereby enabling them to emit a light-emitting signal s1. The latter passes through the deflection means 5 before reaching the emission surfaces of the optical units 22 and 24, as will be described later with reference to Figures 8 to 10.

[0037] The reflection of the light-emitting signal s1 from the obstacle 6 generates a reflected light-emitting signal s2 with sufficient light-emitting power to be captured by the photodiodes 321 and 322 of the multiple photodiodes 32 of the receiving means.

[0038] The receiving means includes, in addition to photodiodes 321 and 322, a blue light filter 8 that filters the light of the reflected emission signal s2 to allow only the blue component of this light to pass through, and a lens 9 that focuses this component toward the photodiodes 321 and 322. The blue light emitted by diodes 121 and 122 generally has a lower emission intensity than that of sunlight. However, the light beams emitted by diodes 121 and 122 are modulated, and by analyzing the modulated signal, it is possible to distinguish this reflected emission signal s2 (including blue light) from external light pollution in the decoding process of the reflected emission signal s2.

[0039] The light-emitting signal s1 transmitted by diodes 121 and 122 encodes a specific sequence of pulses with a width l of 10 ns, which repeats periodically. The pulse sequence is determined to facilitate evaluation of the time shift between its transmission and reception, as will be described later. For example, it may have three consecutive pulses, then only one pulse 60 ns later, then two consecutive pulses 40 ns later, and so on.

[0040] The emitted light-emitting signal s1 strikes the obstacle 6, generating a reflected light-emitting signal s2. Photodiodes 321 and 322 capture the blue component of the reflected light-emitting signal s2 and ambient light, such as sunlight, and supply an electrical signal to the electronic control unit 13. The electronic control unit 13 amplifies the electrical signal and sends it to the decoding means 38. The electronic control unit 13 optionally includes a post-equalization stage in addition to the amplification stage.

[0041] The decoding means 38 includes a counting element Nb for counting photons received by each photodiode 321, 322 as a function of time t, and a thresholding means 34 for thresholding the intensity of the light emission signal received by the photodiodes 321, 322 compared to the light emission intensity of sunlight. This thresholding is consistent with clipping the counting signal Nb as a function of time t when it exceeds the number of photons corresponding to the light emission intensity of the blue component of sunlight, thereby obtaining a thresholded light emission signal s3. Such thresholding suppresses the component caused by sunlight in the received electrical signal. Of course, in this case, the thresholded light emission signal is actually an electrical or digital signal corresponding to the thresholding of the received light emission signal s2.

[0042] The decoding means 38 also includes correlation means 36 for correlating the thresholded light emission signal s3 with the light emission signal s1 transmitted by diodes 121 and 122. These correlation means 36 determine the time shift τ between the thresholded light emission signal and the transmitted light emission signal s1 and transmit this time shift τ to the obstacle detection means 40 of the vehicle 2. The obstacle detection means 40 converts this time shift τ into a distance from the obstacle 6, thus enabling the detection of this obstacle.

[0043] It should be noted that the receiving means of optical units 22 and 24 decodes the reflected light emission signal s2 corresponding to the light emission signal s1 emitted by one or the other of optical units 22 and 24.

[0044] The invention will be described in more detail below, namely, the fact that when the turn signal of the optical unit is activated, the emitting means associated with the other optical unit is configured to cover a minimum detection width in a predetermined portion of the sharpness zone of the receiving means of the vehicle's optical unit, or more precisely, at a predetermined distance in front of the vehicle.

[0045] As shown in Figure 2, with respect to the first embodiment of the invention, when the emission means of the two optical units 22, 24 are operating simultaneously, that is, when neither turn signal is activated, the front left optical unit 22 emits a first light beam 222 that extends horizontally with respect to the road on which the vehicle 2 is traveling, from a first direction d1 that forms an angle γ1 to the left with respect to the normal direction X to the front of the vehicle 2, to a second direction d2 that forms an angle γ2 to the right with respect to the normal direction X to the front, where the normal direction X corresponds to the optical axis of the signal system. The first direction d1 forms the left outer boundary of the emission means of the signal assembly 1, and the second direction d2 forms the left inner boundary of the emission means of the signal assembly 1.

[0046] Similarly, when the emission means of the two optical units 22 and 24 are operating simultaneously, the front right optical unit 24 emits a second light beam 242 that extends horizontally with respect to the road on which the vehicle 2 is traveling, from a third direction d3 forming the right inner boundary of the emission means of the signal assembly 1 to a fourth direction d4 forming the right outer boundary of the emission means of the signal assembly 1. The third direction d3 forms an angle equal to 30 degrees γ2 to the left with respect to the normal direction X to the front of the vehicle 2, and the fourth direction d4 forms an angle equal to 80 degrees γ1 to the right with respect to the normal direction X to the front of the vehicle 2. In this configuration, the first light beam 222 and the second light beam 242 intersect at a distance D1 from the front of the vehicle, which is on the order of approximately 1.7 m (meters), and the optical units 22 and 24 are spaced 2 m apart on the front of the vehicle 2.

[0047] At this distance D1, the first and second light beams 222 and 242 together form a region in front of the vehicle that is continuously illuminated horizontally between the first direction d1 and the fourth direction d4. This region has dimensions measured parallel and horizontally to the front of the vehicle 2, centered on the optical axis OX of the signal assembly 1, with respect to a predetermined distance D1 having length L. This length L is formed by the first and second light beams 222 and 242 and corresponds to the emission width measured at the predetermined distance D1. It can also be said that it corresponds to an angular amplitude of [-80 degrees; +80 degrees] with respect to the optical axis OX of the signal assembly 1.

[0048] For simplicity, in the following description, it is assumed that the emission width L corresponds to the detection width L, that is, that the emission means 12, receiving means 32, and obstacle detection means 40 enable the vehicle 2 to detect any obstacle located between the first and second directions beyond a predetermined distance D1. In practice, the detection width L may be smaller than the emission width because the receiving means 32 is not necessarily configured to receive any reflected light signal s2 having a direction that falls between the first and fourth directions. However, here it is assumed that the detection width L is equal to the width of beams 222, 242 at the point where they intersect, and that this detection width L is greater than the minimum detection width L0 required for safe detection of obstacles in front of the vehicle. This minimum detection width is, for example, 2 meters. Of course, this detection width increases the further away from the vehicle in the sharp zone. Therefore, the minimum detection width is smaller as it is determined closer to the vehicle. The predetermined distance D1 forms the lower limit of a predetermined portion of the sharp zone of the receiving means 32 in this embodiment.

[0049] Figure 3 shows a configuration in which the direction indicator signal of one optical unit, in this case the front right optical unit, is activated, and therefore only the emission means of the other optical unit, in this case the front left optical unit 22, is activated. In order to maintain a minimum detection width L0 at a predetermined distance D1, in this configuration the first beam 222 extends from a first direction d1 that forms an angle γ1 of 80 degrees to the left with respect to direction X, to a second direction d2 in which the angle with direction X is increased compared to the previous configuration. This is because the second direction d2 and direction X now form an angle γ3 to the right that is greater than 80 degrees, for example, 90 degrees. As a result, the second direction d2 intersects with a fourth direction d4 at a distance D2 in front of the vehicle, and this distance D2 is also included in the sharpness zone of the receiving means 32 of the optical units 22, 24. This allows for sufficient detection over a significant distance in front of the vehicle. The predetermined distance D2 forms the upper limit of a predetermined portion of the sharpness zone of the receiving means 32. Therefore, any detection width measurement performed in a predetermined portion must allow for a check to confirm that the detection width in that predetermined portion is greater than the minimum detection width L0.

[0050] Therefore, the angular amplitude of the first beam 222 corresponds to [-80 degrees; +90 degrees] with respect to the optical axis OX of signal assembly 1, which allows the minimum detection width L0 of the preceding configuration to be maintained.

[0051] As a variation of this first embodiment, when a turn signal, in this case a turn signal in the front right optical unit, is activated, the angle γ1 formed by the first direction d1 to the left of direction X can be reduced, while the angle formed by the second direction d2 to the right of direction X can be increased, compared to the configuration in Figure 2. Thus, for example, it is possible to make the angular amplitude of the first beam 222 reach [-30 degrees; +80 degrees] with respect to the optical axis of the front left optical unit 22, which may be sufficient to maintain an illuminated area in front of the vehicle having dimensions of the minimum length, i.e., minimum detectable width L0, measured horizontally between the first direction d1 and the second direction d2 at a predetermined distance D1. In this embodiment of the invention, it is particularly important that the inner angle γ3 is greater than the outer angle γ1 in order to achieve intersection in the sharp zone between the second direction d2 and the fourth direction d4.

[0052] Naturally, when the left turn signal is activated, the second light beam 242 emitted by the front right optical unit 24 is symmetric with respect to the optical axis OX of the signal assembly 1 with respect to the first light beam 222 emitted by the front left optical unit 22 when the right turn signal is activated.

[0053] Finally, in this first embodiment of the invention, it is important to increase the angle formed by the light beam 222, 242 emitted by one of the optical units 22, 24 when the other optical unit 24, 22 is suppressed, and the normal direction X related to the front of the vehicle 2, compared to the configuration in which both optical units 22, 24 are operating together.

[0054] According to the second embodiment shown in Figures 4 and 5, the emission means of the two optical units 22 and 24 are configured to form a first light beam 222a and a second light beam 242a, respectively, and these beams are identical regardless of whether one of the vehicle's turn signal signals is activated or not.

[0055] The first light beam 222a extends horizontally with respect to the road on which the vehicle 2 is moving, from a first direction d1 that forms an angle γ1 of 80 degrees to the left with respect to the normal direction X related to the front of the vehicle 2, to a second direction d2 that forms an angle γ3 of 90 degrees to the right with respect to the normal direction X related to the front of the vehicle 2.

[0056] The second light beam 242a extends horizontally with respect to the road on which the vehicle 2 is moving, and extends from a third direction d3 that forms a 90-degree angle γ3 to the left with respect to the normal direction X related to the front of the vehicle 2, to a fourth direction d4 that forms an 80-degree angle γ1 to the right with respect to the normal direction X related to the front of the vehicle 2.

[0057] In this second embodiment of the invention, the minimum detection width L0 is, for example, 50 cm and is measured at a point obtained by dividing a predetermined distance D1, which is used as the hyperfocal distance of the receiving means 32, by 2. The predetermined distance D1 is, for example, 40 cm and forms the lower limit of a 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 the fourth direction d4 intersect forms the upper limit of a predetermined portion of the sharpness zone of the receiving means 32.

[0058] In this variation, the upper limit of the predetermined portion corresponds to the last sharp surface permitted by the receiving means of the front right or left optical unit. In other words, in this variation, the predetermined portion extends across the depth of field of the optical receiving system.

[0059] At a predetermined distance D1, the first and second light beams 222a and 242a achieve an illumination area in front of the vehicle, the dimensions of which are measured parallel and horizontally to the front of the vehicle 2, equal to the length L, and greater than the minimum detection width L0. Thus, the configuration of the optical units 22 and 24 working together in this second embodiment provides an angular amplitude of detection at least equivalent to that of the configuration in Figure 2.

[0060] Figure 5 shows a configuration in this second embodiment of the invention in which the direction indicator signal of one of the optical units, in this case the front right optical unit 24, is activated, and therefore only the emission means of the other optical unit, in this case the front left optical unit 22, is activated. Since the first beam 222a is identical to that of the preceding configuration, the illumination area in front of the vehicle has a length dimension equal to the minimum detection width L0 at a predetermined distance D1, parallel and horizontal to the front of the vehicle. This configuration is particularly made possible by the fact that the angle γ3 formed by the second direction d2 to the right with respect to the normal direction X is greater than the angle γ1 formed by the first direction d1 to the left with respect to the normal direction X, and by the selection of these two angles γ1 and γ3. Since angle γ1 is generally 80 degrees, this means that angle γ3 is 80 degrees or more.

[0061] Naturally, when the left turn signal is activated, the second light beam 242a emitted by the front right optical unit 24 is symmetric with respect to the optical axis OX of the signal assembly 1 with respect to the first light beam 222a emitted by the front left optical unit 22 when the right turn signal is activated.

[0062] According to the modified embodiment of this second embodiment shown in Figure 6, the emission means of the two optical units 22, 24 are configured to form a first light beam 222b and a second light beam 242b, respectively, and these beams are identical regardless of whether one of the vehicle's turn signal signals is activated or not.

[0063] In this modification, the first light beam 222b extends horizontally with respect to the road on which the vehicle 2 is moving, from a first direction d1 that forms an angle γ1 of 80 degrees to the left with respect to the normal direction X related to the front of the vehicle 2, to a second direction d2 that also forms an angle γ1 of 80 degrees to the right with respect to the normal direction X related to the front of the vehicle 2.

[0064] Similarly, the second light beam 242b extends horizontally with respect to the road on which the vehicle 2 is moving, from a third direction d3 that forms an angle γ1 of 80 degrees to the left with respect to the normal direction X related to the front of the vehicle 2, to a fourth direction d4 that also forms an angle γ1 of 80 degrees to the right with respect to the normal direction X related to the front of the vehicle 2.

[0065] This configuration also achieves an illumination area in front of the vehicle at a predetermined distance D1, which is equal to, for example, the hyperfocal distance divided by 2, or greater than this distance but within the sharpness zone of the receiving means 32, the dimensions of which are measured parallel and horizontally to the front of the vehicle 2 and equal to a length L greater than the minimum detection width L0. Thus, the configuration of the optical units 22, 24 working together in this variation of the second embodiment provides at least the same detection angular amplitude as the configuration in Figure 2.

[0066] Figure 7 shows a configuration in this modified embodiment of the invention in which the turn signal signal of the front left optical unit 22 is activated, and therefore only the emission means of the front right optical unit 24 is activated. Since the second beam 242b is the same as in the preceding configuration, the illumination area in front of the vehicle has a length dimension equal to the minimum detection width L0 at a predetermined distance D1, parallel and horizontal to the front of the vehicle.

[0067] This modified embodiment demonstrates the possibility of realizing the invention with beams that are symmetrical with respect to the normal direction X with respect to the front of the vehicle, provided that the angle formed by each beam with respect to this normal direction X is sufficiently large.

[0068] In Figures 2 to 7, for reasons of visibility, the angles shown do not have values ​​greater than 80 degrees, but rather smaller values, which particularly distorts the perception of the dimensions of the illuminated area in front of the vehicle, which is actually much wider in the parallel and horizontal direction to the front of the vehicle. This means that, in fact, in configurations where the turn signal is not activated and in configurations where the turn signal is activated, the dimension of the minimum detection width L0, which represents the angular amplitude of detection, is always located approximately at the center of the vehicle's optical axis OX, or is centered on that optical axis.

[0069] Since the detection angular amplitude is actually smaller than the emission angular amplitude, the invention maintains the same detection amplitude at a predetermined distance D1, regardless of whether each configuration, i.e., the turn signal signal, is activated or not.

[0070] Figure 8 shows the operation of the emission means of optical units 22, 24 in a second embodiment of the invention. These emission means include a light guide 7 made of, for example, polycarbonate or polymethyl methacrylate (PMMA). The light guide 7 has a first surface 71 machined along its length, and triangular base prisms 7_1 to 7_n are formed on this first surface 71 by removing material. The height of each prism 7_1 to 7_n is parallel to the first surface 71 and oriented perpendicular to the length of the light guide 7, so that light rays passing through its fiber may be reflected at any side of the prism or pass through at least one side of any prism. The volume of each prism 7_1 to 7_n is composed of air.

[0071] The light guide 7 is capable of receiving light emission signals s1 emitted by multiple light-emitting diodes 12. These signals propagate through the light guide 7 by reflection and exit the light guide 7 by refraction via a second surface 72, which is an exit surface located opposite the first surface 71. More specifically, when a light ray reaches the surface of the light guide 7 at an incident angle of less than 40 degrees, it is refracted, while when it reaches the surface of the light guide 7 at an incident angle greater than 40 degrees, it is reflected.

[0072] Therefore, when the light ray s1_1 of the light emission signal s1 reaches the light guide on the prism 7_1 at an incident angle greater than 40 degrees, it is reflected by the surface of the prism 7_1 and heads toward the exit surface 72 at an incident angle β1 of less than 40 degrees. As a result, the light ray s1_1 exits the light guide 7 and contributes to the formation of either illumination beam 222a, 242a, or 222b, 242b.

[0073] When another ray s1_2 of the light emission signal s1 reaches the light guide on prism 7_1 at an incident angle of less than 40 degrees, this ray passes through prism 7_1 and forms an incident angle greater than 40 degrees on the surface of the next prism 7_2. As a result, the ray s1_2 is reflected at this surface of prism 7_2 and heads toward the exit surface 72 at an incident angle β2 of less than 40 degrees. Thus, this ray exits from the exit surface 72 and contributes to the formation of either illumination beam 222a, 242a, or 222b, 242b.

[0074] As the light travels along the light guide 7, the corresponding rays, after passing through more prisms, exit the exit surface 72 with incident angles β1, β2, ..., βn in the range of [-40°;40°] with respect to the normal to the exit surface 72, thereby achieving one of the light beams 222a, 242a, 222b, or 242b.

[0075] This is achieved by the prisms 7_1, ..., 7_n presenting surfaces that form angles α1, α2, ..., αn with respect to the incident light rays from the multiple light-emitting diodes 12, respectively, with respect to the first surface 71, and the angles gradually increase as they move away from the multiple light-emitting diodes 12. Furthermore, the depth of each prism 7_1, ..., 7_n perpendicular to the length of the light guide 7 increases as it moves away from the multiple light-emitting diodes 12. In particular, the base height of the first prism 7_1 is between 0.05 mm and 0.2 mm, for example 0.1 mm, and the base height of the last prism 7_n is between 0.8 mm and 2 mm, for example 1 mm.

[0076] Figures 9 and 10 illustrate the operation of the emission means of optical units 22 and 24 in a first embodiment of the invention. In this first embodiment of the invention, the emission means of optical units 22 and 24 include means for changing the angular amplitude of the other light beam 242, 222 when one of the light beams 222, 242 is suppressed. These changing means use, for example, a deflector 5 (also referenced in Figure 1) having a focal point F which is a lens, and an offset of the light sources contained in the plurality of light-emitting diodes 12 with respect to the optical axis FX of the deflector 5.

[0077] In particular, the multiple light-emitting diodes 12 may include a single light-emitting diode having multiple light-emitting chips, for example, having six chips as shown in Figure 9.

[0078] Four of these six chips form an assembly 12a capable of generating the optical beam 222 or 242 described with reference to Figure 2 when the turn signal is not switched on. This is achieved by the chips of assembly 12a being distributed at the focal plane of the deflector 5, and the rays they emit together with the optical axis FX to form the beam 222 or 242. In particular, the rays emitted by assembly 12a form the maximum angle γ1 measured horizontally with respect to the road on a first side of the optical axis FX, and the maximum angle γ2 measured horizontally with respect to the road on a second side of the optical axis FX, separate from the first side.

[0079] The remaining two chips form assembly 12b. When both the chips of assembly 12a and the chips of assembly 12b emit light, these assemblies 12a and 12b jointly generate the light beam 222 or 242 described with reference to Figure 3 when the turn signal is switched on. This is achieved by assembly 12b remaining at the focal plane of deflector 5 while being off-axis horizontally with respect to the optical axis FX of deflector 5. The position of the chips in assembly 12b is determined so that these chips emit rays that form a minimum angle γ2 on the second side of the optical axis FX, horizontally with respect to the road, and a maximum angle γ3 on the second side of the optical axis FX, also horizontally with respect to the road.

[0080] As a variation, chip assemblies 12a and 12b are replaced by separate light-emitting diodes or separate light-emitting diode assemblies.

[0081] Of course, the invention is not limited to the examples described above, and numerous modifications can be made to these examples without departing from the scope of the invention.

Claims

1. A signal assembly (1) for a vehicle (2), comprising a front left optical unit (22) including a front left turn signal signal and a front right optical unit (24) including a front right turn signal signal, Each optical unit (22, 24) further includes emission means (12, 7, 5) for emitting a high-frequency encoded light-emitting signal (s1) to the outside of the vehicle (2), and receiving means (32) for receiving such light-emitting signals (s2) coming from outside the vehicle (2), wherein the receiving means (32) includes means for connecting to an obstacle detection means (40) of the vehicle (2). The emission means (12, 7, 5) of the front left optical unit (22) is configured to generate a first light beam (222, 222a, 222b) extending between a first direction (d1) forming the left outer boundary and a second direction (d2) forming the left inner boundary when the direction indicator signal is not activated. The emission means (12, 7, 5) of the front right optical unit (24) is configured to generate a second light beam (242, 242a, 242b) extending between a third direction (d3) forming the right inner boundary and a fourth direction (d4) forming the right outer boundary when the direction indicator signal is not activated. The discharge means (12, 7, 5) of the front left optical unit (22) and the discharge means (12, 7, 5) of the front right optical unit (24) are, - Firstly, in a predetermined portion of the sharpening zone of the receiving means of the optical unit, a detection field having a detection width between the first direction (d1) and the fourth direction (d4) can be covered, and this width is greater than or equal to the minimum detection width, and the detection width is measured parallel to the front of the vehicle. - Secondly, the signal assembly (1) can provide a daytime running light function and / or a position light function, wherein the signal assembly (1) is configured such that, at least when the left turn signal is activated, the emission means (12, 7, 5) of the front right optical unit (24) covers the minimum detection width (L0) in a predetermined portion by themselves, and at least when the right turn signal is activated, the emission means (12, 7, 5) of the front left optical unit (22) covers the minimum detection width (L0) in a predetermined portion by themselves.

2. The signal assembly (1) according to claim 1, wherein the first direction, the second direction, the third direction and the fourth direction (d1, d2, d3, d4) are not changed when one of the direction indicator signals is activated.

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

4. The signal assembly (1) according to claim 2, wherein the second direction (d2) forms a rightward angle (γ3) with respect to the normal direction (X) related to the front of the vehicle (2), and the angle (γ3) is greater than the angle (γ1) formed by the first direction (d1) to the left of the normal direction (X), and the third direction (d3) forms a leftward angle (γ3) with respect to the normal direction (X), and the angle (γ3) is greater than the angle (γ1) formed by the fourth direction (d4) to the right of this normal direction (X).

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

6. Each of the first or second light beams (222a, 222b, 242a, 242b) is generated by refracted light emitted from the light guide (7), and in the light guide (7), the corresponding incident light is formed by the ray of the light emission signal (s1) emitted by the emission means (12, 7) for emitting the first or second light beams (222a, 222b, 242a, 242b), and the light guide (7) has at least one emission surface ( The signal assembly (1) according to any one of claims 2 to 5, further comprising 72) and decoupling means (7_1, ..., 7_n) at predetermined points of the light guide (7), wherein the decoupling means (7_1, ..., 7_n) is capable of generating incident light that is refracted at the exit of the light guide (7) by reflecting the light rays propagating in the light guide (7) and directing them toward the at least one exit surface (72).

7. The signal assembly (1) according to claim 6, wherein the decoupling means (7_1, ..., 7_n) is a prism aligned on the surface (71) of the light guide opposite to the at least one exit surface (72), and is configured to decouple the light rays to generate at least the minimum detection width (L0) in the predetermined portion.

8. The signal assembly (1) according to claim 7, wherein the prisms (7_1, ..., 7_n) form a pattern having a depth measured perpendicular to the principal direction of extension of the light guide, which increases from the first end of the light guide adjacent to the light source (12) of the emitting means (12, 7) of the corresponding optical unit (22, 24) toward the second end of the light guide separated from the first end.

9. The signal assembly (1) according to claim 1, wherein the front left optical unit (22) includes means for changing the angular amplitude of the first light beam (222) when the front right turn signal is activated and the emission means (12, 5) of the front right optical unit (24) is suppressed, and the front right optical unit (24) includes means for changing the angular amplitude of the second light beam (242) when the front left turn signal is activated and the emission means (12, 5) of the front left optical unit (22) is suppressed.

10. The signal assembly (1) according to claim 9, wherein the means for changing the angular amplitude of the first light beam (222) is capable of increasing by at least 30° the angle formed by a second direction (d2) that is to the right of the normal direction (X) related to the front of the vehicle (2) and points outward from the vehicle (2) when the forward right turn signal is activated and the emission means (12, 5) of the forward right optical unit (24) is suppressed, and the means for changing the angular amplitude of the second light beam (242) is capable of increasing by at least 30° the angle formed by a third direction (d3) that is to the left of the normal direction (X) when the forward left turn signal is activated and the emission means (12, 5) of the forward left optical unit (22) is suppressed.

11. The signal assembly (1) according to claim 9 or 10, wherein the emission means (12, 5) of each optical unit (22, 24) includes at least one deflector (5) and at least a first light source and a second light source (12a, 12b) positioned offset from each other on the object focal plane of the deflector (5), the deflector (5) is configured to direct a ray of light derived from its focal plane forward of the vehicle (2) to form the first light beam or the second light beam (222, 242), and the means for changing the front left optical unit (22) or the front right optical unit (24) is capable of supplying power to the first light source and / or the second light source (12a, 12b) of the emission means (12, 5), respectively, in response to the operation of the front right turn signal or the front left turn signal.

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