Vehicle assembly including a radar sensor and a multilayer device

Abstract

Disclosed is a vehicle component for a vehicle, comprising: - a radar sensor configured to emit radar waves; - a multilayer device comprising a first layer placed opposite the radar sensor and comprising an input surface of the radar waves, a second layer comprising at least one protrusion, and a third layer comprising an output surface of the radar waves parallel to the input surface, the second layer being adjacent to the first layer and comprising a first joint surface with the first layer and a second joint surface with the adjacent third layer, the first, second and third layers having first, second and third refractive indexes, respectively; - characterized in that, with the first joint surface parallel to the input and output surfaces and the protrusion of the second layer on the second joint surface, the second and third refractive indexes are equal, or, with the second layer having a protrusion on the second joint surface and a protrusion on the first joint surface and the first joint surface parallel to the second joint surface, the refractive indexes of the non-adjacent layers are equal.

Description

Technical Field

[0001] This invention relates to a vehicle component. It has specific, but not limiting, applications in motor vehicles. Background Technology

[0002] Figure 1 The vehicle component 4 shown includes, in a manner known to those skilled in the art, the following:

[0003] - Radar sensor 40, which is configured to transmit radar wave R4;

[0004] - A multilayer device 41 includes a first layer 411 disposed facing the radar sensor 41, a second layer 412 adjacent to the first layer 411 and having a relief 414, and a third layer 413 including an output surface S4 for radar waves R4, wherein the first layer 411, the second layer 412, and the third layer 413 each have different refractive indices.

[0005] Radar sensor 40 is designed to have a defined field of view (FOV). It detects objects in the external environment of the motor vehicle.

[0006] One drawback of this prior art is that the protrusion 414 creates a prism effect that obstructs the transmission of radar waves R4. These radar waves are deflected as they pass through the multi-layer device 41. Therefore, the field of view (FOV) of the radar sensor 40 includes a blind zone Za. This means that objects located in the external environment of the vehicle within the blind zone Za may not be detected.

[0007] In this context, the object of the present invention is to provide a vehicle component that allows for the resolution of the aforementioned disadvantages. Summary of the Invention

[0008] Therefore, the present invention provides a vehicle component for a vehicle, the vehicle component comprising:

[0009] - A radar sensor configured to emit radar waves;

[0010] - A multilayer device comprising a first layer disposed facing the radar sensor and including an input surface for radar waves, a second layer including at least one protrusion, and a third layer including an output surface for radar waves parallel to the input surface, the second layer being adjacent to the first layer and including a first bonding surface together with the first layer and a second bonding surface together with the adjacent third layer, wherein the first layer, the second layer and the third layer respectively include a first refractive index, a second refractive index and a third refractive index;

[0011] The second refractive index and the third refractive index are equal when the first bonding surface is parallel to the input surface and the output surface, and the protrusion of the second layer is on the second bonding surface; or, when the second layer has protrusions on the second bonding surface and protrusions on the first bonding surface, and the first bonding surface is parallel to the second bonding surface, the refractive indices of non-adjacent layers are equal.

[0012] According to a non-limiting embodiment, the vehicle component may, individually or in any technically possible combination, further include one or more additional features selected from the following.

[0013] According to a non-limiting embodiment, the radar sensor is a millimeter-wave, ultra-high frequency, or microwave radar sensor.

[0014] According to a non-limiting embodiment, when the first bonding surface is parallel to the input and output surfaces, and the protrusions of the second layer are on the second bonding surface, the second refractive index and the first refractive index are equal.

[0015] According to a non-limiting embodiment, the input surface and the output surface are flat.

[0016] According to a non-limiting embodiment, the input surface and the output surface are curved.

[0017] According to a non-limiting embodiment, the input surface and the output surface have a radius of curvature Rm = γ*E(da)max, where E is the thickness of the multilayer device, (da)max is the angular position error tolerance of the radar sensor, and γ is a factor that depends on the maximum angle of the radar sensor's field of view and the third refractive index of the third layer.

[0018] According to a non-limiting embodiment, the thickness of the second layer is at most one-tenth the thickness of the first and third layers, or the thickness of the second layer is at least ten times smaller than the thickness of the first and third layers.

[0019] According to a non-limiting embodiment, the first layer is an optical layer, the second layer is a film layer or an opalescent / milky white layer, and the third layer is an external output lens.

[0020] According to a non-limiting embodiment, the multilayer device forms an illuminated sign or radome.

[0021] A multilayer device is also proposed, which is configured to face a radar sensor and is configured to emit radar waves. The multilayer device includes a first layer configured to face the radar sensor and including an input surface for radar waves, a second layer including at least one protrusion, and a third layer including an output surface for radar waves parallel to the input surface. The second layer is adjacent to the first layer and includes a first bonding surface together with the first layer and a second bonding surface together with the adjacent third layer. The first layer, the second layer, and the third layer each include a first refractive index, a second refractive index, and a third refractive index, respectively.

[0022] The second refractive index and the third refractive index are equal when the first bonding surface is parallel to the input surface and the output surface, and the protrusion of the second layer is on the second bonding surface; or, when the second layer has protrusions on the second bonding surface and protrusions on the first bonding surface, and the first bonding surface is parallel to the second bonding surface, the refractive indices of non-adjacent layers are equal. Attached Figure Description

[0023] A better understanding of the invention and its various applications will be gained by reading the following description and referring to its accompanying drawings, wherein:

[0024] [ Figure 1 [Illustration] is a schematic diagram of a vehicle assembly including radar sensors and multi-layer devices, based on existing technology;

[0025] [ Figure 2 [Illustration] is a schematic diagram of a vehicle component according to a non-limiting embodiment of the present invention, wherein the vehicle component includes a radar sensor and a multi-layer device;

[0026] [ Figure 3 ]yes Figure 2 A schematic diagram of a multilayer device for a vehicle component according to a first non-limiting embodiment, wherein the multilayer device includes a first layer, a second layer having protrusions, and a third layer;

[0027] [ Figure 4 [This is based on] Figure 2 A schematic diagram of a multilayer device according to a second non-limiting embodiment of a vehicle component, wherein the multilayer device includes a first layer, a second layer having protrusions, and a third layer;

[0028] [ Figure 5 [This is based on a non-limiting embodiment] Figure 2 A schematic diagram of two radar waves emitted by sensors on a vehicle component, one of which passes through... Figure 2In a multi-layer device, the first, second, and third layers are connected without passing through the raised ramp of the second layer, while another layer passes through the first, second, and third layers by passing through the raised ramp of the second layer.

[0029] [ Figure 6 ]yes Figure 2 A schematic diagram of a multilayer device for a vehicle component according to a third non-limiting embodiment, wherein the multilayer device includes a first layer, a second layer having protrusions, and a third layer.

[0030] Unless otherwise stated, structurally or functionally identical elements appearing in various figures use the same reference numerals. Detailed Implementation

[0031] refer to Figures 2 to 6 Vehicle component 1 of a vehicle 2 according to the present invention is described. Vehicle component 1 is also referred to as vehicle system 1. In one non-limiting embodiment, vehicle 2 is a motor vehicle. Motor vehicle is understood to mean any type of motor vehicle. Throughout the remainder of the description, this embodiment is considered a non-limiting example. Throughout the remainder of the description, vehicle 2 is therefore also referred to as motor vehicle 2. In one non-limiting embodiment, vehicle component 1 is integrated into the grille / radiator grille of motor vehicle 2. In another non-limiting embodiment, vehicle component 1 may be integrated into a body component located at the rear of motor vehicle 2.

[0032] like Figure 2 As shown, vehicle component 1 (also referred to as vehicle device 1) includes:

[0033] - Radar sensor 10, configured to transmit radar wave R1; - Multilayer device 11.

[0034] These components will be described below.

[0035] The radar sensor 10 will be described below. For example... Figure 2As shown, radar sensor 10 is configured to face multilayer device 11. In a non-limiting embodiment, radar sensor 10 is a millimeter-wave (between 24 GHz and 300 GHz) or ultra-high frequency (UHF) (between 300 MHz and 81 GHz) or microwave (between 1 GHz and 300 GHz) radar sensor. In a non-limiting alternative embodiment, radar sensor 10 operates at radar frequencies in the range of 76 GHz to 81 GHz. In a non-limiting embodiment, radar wave R1 is transmitted in a frequency band in the range of 100 MHz to 5 GHz. Therefore, in a non-limiting example, if radar sensor 10 operates at a radar frequency of 77 GHz (i.e., wavelength λ is 3.95 mm) and has a frequency band of 1 GHz, then radar sensor 10 will operate in a frequency band of 76.5 GHz to 77.5 GHz. Therefore, radar wave R1 will be transmitted in a frequency range of 76.5 GHz to 77.5 GHz, i.e., the wavelength λ range Δ1 is 3.87 mm to 3.92 mm. Therefore, in another non-limiting example, if radar sensor 10 operates at a radar frequency of 78.5 GHz and has a frequency band of 5 GHz, then radar sensor 10 will operate in the frequency band of 76 GHz to 81 GHz. Therefore, radar wave R1 will be transmitted in the frequency range of 76 GHz to 81 GHz, that is, the wavelength λ ranges Δ1 from 3.701 mm to 3.945 mm.

[0036] like Figure 2 As shown, radar sensor 10 has a field of view (FOV). The emitted radar wave R1 arrives at the multilayer device 11 at an incident angle θ. In one non-limiting embodiment, the incident angle θ ranges between 0° and + / -30°. Therefore, the field of view (FOV) varies between -30° and +30°. The center of the field of view (FOV) is at an angle of 0° relative to the longitudinal axis of the vehicle (also referred to as the vehicle axis). In another non-limiting embodiment, the field of view (FOV) thus varies between -90° and +45°. The center of the field of view (FOV) is at an angle of -45° relative to the vehicle axis, and the incident angle θ of the radar wave R1 on the multilayer device 11 remains close to 0° (the vehicle assembly 1 is positioned at approximately 45° relative to the vehicle axis). Radar sensor 10 emits radar wave R1 as a transmission beam FR1 within its field of view (FOV). The transmission beam FR1 defines the field of view (FOV) of radar sensor 10.

[0037] Radar sensor 10 is configured to scan the external environment of motor vehicle 2 by emitting radar waves R1. For example... Figure 2 As shown, the radar sensor 10 therefore includes:

[0038] - At least one transmitter antenna 100 is configured to transmit radar wave R1 (also known as primary radar wave R1 or transmitted radar wave R1).

[0039] - At least two receiver antennas 101 are configured to receive the returned radar wave R2 (also known as radar wave R2 or secondary radar wave R2).

[0040] The radar sensor 10 also includes at least one transmitter 103 configured to generate primary radar waves R1 and at least one receiver 104 configured to process received returned secondary radar waves R2. In a non-limiting embodiment, a single electronic component can be used for both transmitting and receiving functions. Therefore, one or more transceivers will be present. The transmitter 103 generates primary radar waves R1, which are then transmitted by the transmitter antenna 100 and reflected at an object 3 (in this case, a pedestrian in the non-limiting example shown) in the external environment of the motor vehicle 2. It should be noted that the object 3 is also referred to as the target object 3. Therefore, the reflected radar waves are the waves that are transmitted back to the radar sensor 10. These waves are secondary radar waves R2 received by the receiver antenna 101. These waves are radar waves retransmitted to the radar sensor 10. In a non-limiting embodiment, the primary radar waves R1 and the secondary radar waves R2 are radio frequency waves. In one non-limiting embodiment, the radar sensor 10 includes a plurality of transmitters 103 and a plurality of receivers 104.

[0041] Transmitter antenna 100 (also referred to as antenna 100) is configured to transmit primary radar waves R1 generated by transmitter 103. Receiver antenna 101 (also referred to as antenna 101) is configured to receive secondary radar waves R2 and transmit them to receiver 104, which then processes them. Phase shift (also known as phase difference) The object 3 exists between the secondary radar waves R2 received by the respective receiver antennas 101, which allows the angular position Pos of the object 3 relative to the vehicle 2, which is located in the external environment of the vehicle 2. In a non-limiting embodiment, antennas 100, 101 are patch antennas or slot antennas.

[0042] In one non-limiting embodiment, antennas 100, 101, transmitter 103, and receiver 104 are disposed on a printed circuit board 105. In one non-limiting embodiment, the printed circuit board is a rigid printed circuit board, also known as a PCBA (Printed Circuit Board Assembly) or a flexible printed circuit board, also known as a "flexible board".

[0043] The radar sensor 10 also includes an electronic control unit 106 configured to control the transmitter 103 and the receiver 104. Since radar sensors are known to those skilled in the art, they are not described in more detail herein. In a non-limiting embodiment, phase shift... Measured by electronic control unit 106 or receiver 104.

[0044] The multi-layer device 11 is described below. For example... Figures 3 to 6 As shown, it includes:

[0045] -First layer 111;

[0046] - Second layer 112, which includes at least one protrusion 114;

[0047] -Third floor 113.

[0048] In a non-limiting embodiment, the multilayer device 11 is an illuminated sign or radome.

[0049] The first layer 111 is configured to face the radar sensor 10 and includes an input surface S1 for radar waves R1. The input surface S1 forms a refractive index between the material of the first layer 111, which has a refractive index n1, and air, which has a refractive index n0 = 1. Radar waves R1 arrive at this refractive index S1 at an incident angle θ1. They pass through the first layer 111, the second layer 112, and the third layer 113. They exit from the third layer 113 at an incident angle θ3. The refractive index n1 is also referred to as the first refractive index n1.

[0050] In a non-limiting embodiment, the first layer 111 is an optical layer. The optical layer 111 allows light to be emitted from one or more light sources (not shown). The optical layer 111 forms a dielectric element. In a non-limiting embodiment, the dielectric element is made of a plastic, glass, or ceramic material. In a non-limiting example, the plastic is polycarbonate (PC). As a reminder, unlike conductive materials, dielectric materials are non-conductive, thus allowing radar waves R1 to pass through. The optical layer 111 is a transparent layer to the radar sensor 10, i.e., transparent to radar waves R1 and R2. In a non-limiting embodiment, the optical layer 111 may be a light guide or a lens.

[0051] The second layer 112 is disposed between the first layer 111 and the third layer 113. It is adjacent to both the first layer 111 and the third layer 113. Therefore, the second layer 112 includes a first mating surface Sj1 (also referred to as mating surface Sj1) with the first layer 111 and a second mating surface Sj2 (also referred to as mating surface Sj2) with the third layer 113. It has a refractive index n2, also referred to as a second refractive index n2. The second layer 112 has protrusions 114 that allow for the creation of 3D patterns. The protrusions 114 have a 3D shape. This 3D shape is typically specified by the vehicle manufacturer according to a design and is therefore associated with the vehicle 2. Figure 3 , Figure 4 and Figure 6 In one non-limiting example shown, protrusion 114 is a prism. It is pyramidal in shape. In another non-limiting example, not shown, protrusion 114 is trapezoidal in shape. In yet another non-limiting example, not shown, protrusion 114 may be a ramp. Therefore, in the case of an illuminated sign, the second layer 112 allows for the generation of a pattern on the illuminated sign. Figure 3 , Figure 4 and Figure 6 As shown, the protrusion 114 forms an angle β with respect to the normals of the mating surfaces Sj1 and Sj2. It should be noted that the smaller the angle β, the greater the slope of the protrusion 114. The second layer 112 is transparent to the radar sensor 10.

[0052] In a first non-limiting embodiment, the second layer 112 is a colored film layer. In a non-limiting alternative embodiment, it is approximately 0.4 mm thick. In this case, in a non-limiting example, the film layer 112 may be deposited on a pre-formed first layer 111 and then re-formed using the same material as the first layer 111 to produce a third layer 113.

[0053] In a second, non-limiting embodiment, the second layer 112 is an opalescent layer. In a non-limiting alternative embodiment, it is approximately 2.5 mm thick. In this case, in a non-limiting example, the second layer 112 is produced by multiple injections.

[0054] The third layer 113 is adjacent to the second layer 112. It is disposed on the side opposite to the radar sensor 10, i.e., on the exterior of the vehicle 2. In a non-limiting embodiment, the third layer 113 is an external output lens. In a non-limiting embodiment, the third layer 113 is made of plastic. In one non-limiting example, the plastic is polycarbonate (PC). The third layer 113 includes an output surface S3 for radar wave R1. The output surface S3 is parallel to the input surface S1. The third layer 113 is transparent to the radar sensor 10 and visible light.

[0055] exist Figure 3 and Figure 6 In one non-limiting embodiment shown, the second layer 112 includes protrusions 114 on the second mating surface Sj2. Figure 4 In one non-limiting embodiment shown, the second layer 112 includes two protrusions 114, one on the second mating surface Sj2 and the other on the first mating surface Sj1.

[0056] exist Figure 3 In the first non-limiting embodiment shown, the protrusion 114 of the second layer 112 is on the second bonding surface Sj2. The first bonding surface Sj1 does not have any protrusion 114. The first bonding surface Sj1 is not parallel to the second bonding surface Sj2. The output surface S3 and the input surface S1, which are parallel to each other, are flat. Furthermore, the first bonding surface Sj1 is parallel to the input surface S1 and the output surface S3. In this first non-limiting embodiment, n2 = n3. Therefore, if the first bonding surface Sj1 is parallel to the input surface S1 and the output surface S3, and if the protrusion 114 of the second layer 112 is on the second bonding surface Sj2, then the second refractive index n2 and the third refractive index n3 are equal. By making n2 = n3, the multilayer device 11 is regarded by the radar sensor 10 as an equivalent multilayer device, which includes two layers (the second layer 112 and the third layer 113) having surfaces S3, Sj2, and Sj1 that are parallel to each other. θ3 = θ1 is obtained. If, as in the prior art, the second refractive index n2 differs from the third refractive index n3, then the angle of incidence θ3 will differ from the angle of incidence θ1, and the smaller the angle β, the greater the difference between θ3 and θ1. The smaller the angle β, the larger the blind zone Za (also known as the shadow area as seen in the prior art) of the field of view (FOV). Therefore, by taking n2 = n3, even with the presence of the protrusion 114 on the second layer 112, there is no longer any blind zone Za in the FOV of the radar sensor 10. It should be noted that n2sin i2 = n3sin i3, where i2 is the angle of incidence of the radar wave R1 relative to the surface of the protrusion 114, and i3 is the corresponding angle of refraction. Therefore, i3 = i2. Thus, there is no deflection of the radar wave R1 between the second layer 112 and the third layer 113.

[0057] In a non-limiting alternative embodiment of the first non-limiting embodiment, n2 is further made to equal n1. Therefore, n3 = n2 = n1. Thus, if the first bonding surface Sj1 is parallel to the input surface S1 and the output surface S3, and if the protrusion 114 of the second layer 112 is on the second bonding surface Sj2, then the second refractive index n2 and the first refractive index n1 are equal. A uniform arrangement of layers 11 exists for the radar sensor 10. The phase difference between the two returning radar waves R2... The calculation is simple. Where d1 is the distance between the two receiver antennas 101 (e.g., Figure 1 As shown), i1 is the incident angle of the returned radar wave R2 on the multilayer device 11 (as shown). Figure 1 (As shown). Phase difference The calculation does not require correction. The thickness e2 of the second layer 112 does not need to be very small relative to the thicknesses e1 and e3 of the first layer 111 and the third layer 113.

[0058] exist Figure 4 In the second non-limiting embodiment shown, the second layer 112 includes protrusions 114 on the second bonding surface Sj2 and on the first bonding surface Sj1. Furthermore, the first bonding surface Sj1 is parallel to the second bonding surface Sj2. The parallel output surface S3 and input surface S1 are flat. In this second non-limiting embodiment, n1 = n3. Therefore, if the second layer 112 has two protrusions 114, one on the second bonding surface Sj2 and the other on the first bonding surface Sj1, the refractive indices n1 and n3 of the non-adjacent layers (first layer 111 and third layer 113) are equal. By making n1 = n3, the multilayer device 11 is considered by the radar sensor 10 as an equivalent multilayer device comprising two layers (first layer 111 and third layer 113) having parallel surfaces S3, Sj2, Sj1, and S1. θ3 = θ1 is obtained. If, as in the prior art, the second refractive index n1 differs from the third refractive index n3, then the incident angle θ3 will differ from the incident angle θ1, and the smaller the angle β, the greater the difference between θ3 and θ1. The smaller the angle β, the larger the blind zone Za (also known as the shadow area as seen in the prior art) of the field of view (FOV). Therefore, by taking n1 = n3, no blind zone Za exists in the FOV of the radar sensor 10.

[0059] Figure 5 The diagram shows radar wave R11 that passes through the first layer 111, the second layer 112, and the third layer 113 but does not pass through the slope of protrusion 114, and radar wave R12 that passes through the slope of protrusion 114 and passes through the first layer 111, the second layer 112, and the third layer 113. Then: θ3=i and θ3′=asin(n3sin(b-asin(n1 / n3 sin(b-asin(sin(i′) / n1)))), where θ3 is the incident angle of radar wave R11, θ3′ is the incident angle of radar wave R12, and b=π / 2-β. When n1=n3, then θ3′=i′ (i.e., θ31′=i′, as shown in the diagram). Figure 5As shown), and there is no blind zone Za. If this is not the case, for example if n1 = 1.6, n3 = 1.8, b = 30°, where 20° is the angular position of the corner 114c of the protrusion 114, and i and i′ tend toward this angular position of corner 114c, then there will be radar wave R1′2, where θ3 = i = 20°, but θ3′ ≠ i′ = 30° (i.e., θ32′ ≠ i′ = 30°, as shown). Figure 5 As shown), there is a 10° blind zone Za. It should be noted that in the non-limiting example shown, the protrusion 114 is assumed to be trapezoidal in shape. Therefore, since n1 = n3, even if the protrusion 114 exists on the second layer 112, there is no longer any blind zone Za.

[0060] exist Figure 6 In the third non-limiting embodiment shown, the protrusion 114 of the second layer 112 is on the second bonding surface Sj2. The first bonding surface Sj1 has no protrusion 114. The first bonding surface Sj1 is not parallel to the second bonding surface Sj2. The output surface S3 and the input surface S1, which are parallel to each other, are curved. Furthermore, the first bonding surface Sj1 is parallel to the input surface S1 and the output surface S3. It should be noted that having a curved output surface S3 and a curved input surface S1 allows for a smaller angle of incidence θ1 than if the output surface S3 and the input surface S1 were flat. Therefore, there are fewer reflected reflections hitting the radar sensor 10, and less interference with the radar sensor 10. The input surface S1 and the output surface S3 have a radius of curvature Rm = γ * E(da)max, where E is the thickness of the multilayer device 11, (da)max is the angular position error tolerance of the radar sensor 10, and γ is a factor depending on the maximum angle of the field of view (FOV) of the radar sensor 10 and the refractive index n3 of the third layer 113. Then:

[0061] [Mathematics 1]

[0062]

[0063] Calculate Rm for input surface S1 and Rm for output surface S3. Therefore, n equals n1 or n3, and amax is the maximum value of θ1 (for S1) and the maximum value of θ3 (for S3), where θ1 and θ3 are the incident angles relative to the direction perpendicular to and parallel to the transmission axis of radar sensor 10, which is the axis extending from the transmitting antenna or transmitter antenna 100 toward the center of the field of view (FOV).

[0064] In this third non-limiting embodiment, n2 = n3. Therefore, if the first bonding surface Sj1 is parallel to the input surface S1 and the output surface S3, and if the protrusion 114 of the second layer 112 is on the second bonding surface Sj2, then the second refractive index n2 and the third refractive index n3 are equal. By making n2 = n3, the multilayer device 11 is considered by the radar sensor 10 as an equivalent multilayer device comprising two layers (second layer 112 and third layer 113) having surfaces S3, Sj2, and Sj1 parallel to each other. θ3 = θ1 is obtained. If, as in the prior art, the second refractive index n2 is different from the third refractive index n3, then the angle of incidence θ3 will be different from the angle of incidence θ1, and the smaller the angle β, the greater the difference between θ3 and θ1. The smaller the angle β, the larger the blind zone Za (also known as the shadow zone) of the field of view (FOV). Therefore, by taking n2 = n3, even with the presence of a protrusion 114 on the second layer 112, there is no longer any blind zone Za in the field of view (FOV) of the radar sensor 10. It should be noted that n2sin i2 = n3sin i3, where i2 is the angle of incidence of the radar wave R1 relative to the surface of the protrusion 114, and i3 is the corresponding angle of refraction.

[0065] In a non-limiting alternative embodiment of this third non-limiting embodiment, n2 is further made equal to n1. Therefore, if the first bonding surface Sj1 is parallel to the input surface S1 and the output surface S3, and if the protrusion 114 of the second layer 112 is on the second bonding surface Sj2, then the second refractive index n2 and the first refractive index n1 are equal.

[0066] It should be noted that, when Figure 3 , 4 As shown in Figure 6, when one or more protrusions 114 are present, the phase difference between the two measured return radar waves R2 is... Not following traditional formulas Instead, it follows a more complex law that depends on the position of the receiver antennas 101 relative to each other and relative to the multilayer device 11, and on the protrusion 114. Furthermore, conventionally, a correction law needs to be applied to the phase shift. The measurement is performed to feed back to the value calculated according to a conventional formula. To avoid applying a correction law that would change for each new design of vehicle component 1, in a non-limiting embodiment, the thickness e2 of the second layer 112 is at most one-tenth the thicknesses e1 and e3 of the first layer 111 and the third layer 113; the thickness e2 of the second layer 112 is at least ten times smaller than the thicknesses e1 and e3 of the first layer 111 and the third layer 113. It should be noted that e1, e2, and e3 are average thicknesses. Therefore, the phase shift... The measurement results will be close enough to the values ​​calculated according to conventional laws. The differences will be negligible.

[0067] Of course, the description of the present invention is not limited to the embodiments and fields described above. Therefore, in another non-limiting embodiment, the radar sensor 10 includes one or more transmitter antennas 100 and two or more receiver antennas 101. Therefore, in another non-limiting embodiment, the multilayer device 11 includes three or more layers. Therefore, in a non-limiting example, the multilayer device 11 may include a scattering layer, and / or a reflective layer and / or an opaque layer.

[0068] Therefore, the present invention as specifically described has the following advantages:

[0069] - To prevent the calculation of the angular position of the target object 3 from being affected by the 3D shape of the layers in the multilayer device 11:

[0070] - Allows for the elimination of blind spots (Za).

Claims

1. A vehicle assembly (1) for a vehicle (2), the vehicle assembly (1) comprising: - a radar sensor (10) configured to emit radar waves (R1); - a multilayer device (11) comprising a first layer (111) arranged facing the radar sensor (10) and comprising an input surface (SI) of the radar waves (R1), a second layer (112) comprising at least one protrusion (114), the second layer being adjacent to the first layer (111) and comprising a first joint surface (Sj1) jointed together with the first layer (111) and a second joint surface (Sj2) jointed together with the adjacent third layer (113), the third layer (113) comprising an output surface (S3) of the radar waves (R1), the output surface being parallel to the input surface (SI), the first layer (111), the second layer (112) and the third layer (113) comprising a first refractive index (n1), a second refractive index (n2) and a third refractive index (n3), respectively; - characterized in that, in the case where the first joint surface (Sj1) is parallel to the input surface (SI) and to the output surface (S3), and the protrusion (114) of the second layer (112) is on the second joint surface (Sj2), the second refractive index (n2) and the third refractive index (n3) are equal, or in the case where the second layer (112) has a protrusion (114) on the second joint surface (Sj2) and a protrusion (114) on the first joint surface (Sj1), and the first joint surface (Sj1) is parallel to the second joint surface (Sj2), the refractive indices (n1, n3) of the non-adjacent layers (111, 113) are equal, wherein the input surface (SI) and the output surface (S3) are curved, and wherein the input surface (SI) and the output surface (S3) have a radius of curvature Rm = γ*E(da)max, where E is the thickness of the multilayer device (11), (da)max is the angular position error tolerance of the radar sensor (10), and γ is a factor depending on the maximum angle of the field of view (FOV) of the radar sensor (10) and the third refractive index (n3) of the third layer (113).

2. The vehicle component (1) according to claim 1, wherein The radar sensor (10) is a millimeter wave or ultra-high frequency wave or microwave radar sensor.

3. The vehicle component (1) according to claim 1 or 2, wherein in the case where the first joint surface (Sj1) is parallel to the input surface (SI) and to the output surface (S3), and the protrusion (114) of the second layer (112) is on the second joint surface (Sj2), the second refractive index (n2) and the first refractive index (n1) are equal.

4. The vehicle component (1) according to claim 1 or 2, wherein The thickness (e2) of the second layer (112) is at most one tenth of the thickness (el, e3) of the first layer (111) and of the third layer (113).

5. The vehicle component (1) according to claim 1 or 2, wherein The first layer (111) is an optical layer, the second layer (112) is a film layer or an opalescent layer, and the third layer (113) is an external output lens.

6. The vehicle component (1) according to claim 1 or 2, wherein The multilayer device (11) forms an illuminated sign or a radome.

7. A multilayer device (11) arranged facing a radar sensor (10) configured to emit radar waves (Rl), the multilayer device comprising a first layer (111) arranged facing the radar sensor (10) and comprising an input surface (Sl) of the radar waves (Rl), a second layer (112) comprising at least one protrusion (114), the second layer being adjacent to the first layer (111) and comprising a first junction surface (Sjl) joined together with the first layer (111) and a second junction surface (Sj2) joined together with the adjacent third layer (113), the third layer (113) comprising an output surface (S3) of the radar waves (Rl) parallel to the input surface (Sl), the first layer (111), the second layer (112) and the third layer (113) comprising a first refractive index (nl), a second refractive index (n2) and a third refractive index (n3) respectively; - characterized in that, in the case where the first junction surface (Sjl) is parallel to the input surface (Sl) and to the output surface (S3) and the protrusion (114) of the second layer (112) is located on the second junction surface (Sj2), the second refractive index (n2) and the third refractive index (n3) are equal, or in the case where the second layer (112) has a protrusion (114) located on the second junction surface (Sj2) and a protrusion (114) located on the first junction surface (Sjl) and the first junction surface (Sjl) is parallel to the second junction surface (Sj2), the refractive indices (nl, n3) of the non-adjacent layers (111, 113) are equal, wherein the input surface (Sl) and the output surface (S3) are curved, and wherein the input surface (Sl) and the output surface (S3) have a radius of curvature Rm = γ*E(da)max, where E is the thickness of the multilayer device (11), (da)max is the angular position error tolerance of the radar sensor (10), and γ is a factor depending on the maximum angle of the field of view (FOV) of the radar sensor (10) and the third refractive index (n3) of the third layer (113).

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