Colored module, related motor vehicle and related color changing method

Abstract

One aspect of the invention relates to a colored module (10) for a body part of a motor vehicle, comprising:-a structure (S) comprising:-a flexible substrate (2),-a metal layer (3) delimited by a first face (F1) and a second face (F2), the first face (F1) being in contact with a face (F0) of the flexible substrate (2),-a layer (4) of electrochromic organic material delimited by a third face (F3) and a fourth face (F4), the first face (F1) being in contact with a face (F0) of the flexible substrate (2), and the second face (F2) being in contact with a face (F0) of the flexible substrate (2); a transparent waveguide (5) in contact with the fourth face (F4),-at least one pair of electrodes connected to the electrochromic organic material layer (4),-a measurement photodetector (7) for measuring the ambient light flux,-an illumination light source (8) for illuminating the waveguide (5) when the ambient light flux is below a threshold value.

Description

Technical Field

[0001] The invention belongs to the technical field of motor vehicle bodies and improving the aesthetic appearance of motor vehicles.

[0002] The invention relates to a coloured module and to a motor vehicle comprising such a module. The invention also relates to a method for changing the colour of a module according to the invention. Background Art

[0003] Recent years have seen the development of motor vehicles that can change color in real time and can therefore be customized. In this type of vehicle, a covering is placed on the body of the vehicle. This covering is designed using electronic ink technology, such as E-Ink technology. Black and white particles are bathed in a fluid contained between two flexible sheets that act as electrodes and are directed towards one or the other of these sheets in response to the application of an electric field, making it possible to define a color at a specific position between the two sheets. This makes it possible to customize the appearance of these vehicles. However, the range of colors currently available is limited to grayscale. In addition, with this technology, the covering is invisible at night. Summary of the invention

[0004] The present invention provides an alternative to known prior art solutions, making it possible to customise the vehicle with a wider range of colours and to customise the vehicle both during the day and at night.

[0005] A first aspect of the present invention relates to a coloured module, comprising:

[0006] - a structure comprising:

[0007] - flexible substrate,

[0008] a metal layer defined by a first face and a second face, the first face being in contact with the face of the flexible substrate,

[0009] - a layer of electrochromic organic material delimited by a third face and a fourth face, the third face being in contact with the second face,

[0010] - a transparent waveguide in contact with the fourth surface,

[0011] - at least one pair of electrodes connected to the electrochromic organic material layer,

[0012] - a measuring photodetector for measuring the ambient light flux,

[0013] - an illumination light source for illuminating the waveguide when the ambient light flux is below a threshold.

[0014] By means of the present invention, the color of the colored module can be controlled by applying a voltage to the terminals of the at least one pair of electrodes. Furthermore, due to the presence of the transparent waveguide and the illumination light source, the color applied to the colored module is visible both during the day and at night. The colored module can be attached to a vehicle body part.

[0015] Advantageously:

[0016] - the electrochromic organic material layer is structured into N elements, at least two of the N elements having different thicknesses,

[0017] - the at least one pair of electrodes comprises N pairs of electrodes, each of the N pairs of electrodes being connected to an edge of a respective one of the N elements. Thus, the body part may be multi-colored and represent a structured pattern, the colors of the different colored elements of which may be controlled by varying the voltages at the terminals of the N pairs of electrodes.

[0018] Advantageously, the electrochromic organic material is PEDOT.

[0019] Advantageously, the flexible substrate is made of silicone, polycarbonate or PMMA. Thus, the colored module can cover vehicle bodies of different shapes.

[0020] Advantageously, the transparent waveguide is a transparent film comprising microstructures.Thus, the thickness of the colored module can be relatively thin and the colored module can be attached to the vehicle without affecting its aesthetic appearance.

[0021] Advantageously, the structure has a thickness of 50 microns.

[0022] Advantageously, the module further comprises a proximity sensor. Thus, if the module is attached to a vehicle body part, the color of the module can be controlled and changed when the vehicle approaches an object (such as a pedestrian or another vehicle), whereupon the body part acts as a warning device.

[0023] A second aspect of the invention relates to a motor vehicle comprising a module according to the first aspect of the invention.

[0024] Advantageously, the module is attached to a door of a motor vehicle. The colour of the door of the motor vehicle can thus be customised.

[0025] Advantageously, the module is attached to the grille of a motor vehicle. Thus, the color of elements of the grille, such as the logo of the motor vehicle, can be customized.

[0026] A third aspect of the invention relates to a method for changing the color of a module according to the first aspect of the invention, the method comprising the following steps:

[0027] - a step of measuring the ambient light flux by the photodetector,

[0028] - a step of illuminating the transparent waveguide by the light source if the measured ambient light flux is below the threshold value,

[0029] - A step of applying between at least one of the pair of electrodes a voltage between a minimum voltage of -10 V and a maximum voltage of +10 V. Thus, the invention makes it possible to change the color of the module and make this color visible also at night by controlling the voltage on the terminals of the at least one pair of electrodes.

[0030] Advantageously, the voltage applied in the applying step depends on the signal received by the proximity sensor.Thus, when the module is attached to a vehicle body part, the invention makes it possible to customize the color of the body part according to an object detected in the vicinity of the motor vehicle, such as another motor vehicle or a pedestrian.

[0031] The invention and its various applications will be better understood by reading the following description and examining the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] These figures are presented by way of indication and in no way limit the invention.

[0033] - Figure 1 A motor vehicle is shown having a first color.

[0034] - Figure 2 A second color different from the first color is shown. Figure 1 of motor vehicles.

[0035] - Figure 3 A multilayer structure according to the invention is shown.

[0036] - Figure 4 The dependence of the wavelength reflected by a layer of electrochromic organic material on the thickness of this layer is shown.

[0037] - Figure 5 A coloured module according to the first aspect of the invention is shown.

[0038] - Figure 6 A portion of a structured electrochromic organic material layer comprising a plurality of pixels is shown.

[0039] - Figure 7 The daytime operation of a coloured module according to the first aspect of the invention is schematically illustrated.

[0040] - Figure 8 The nighttime operation of a colored module according to the first aspect of the invention is schematically illustrated. DETAILED DESCRIPTION

[0041] Figure 1A motor vehicle 20 having a first color is shown. Arrow F indicates the forward travel direction of the motor vehicle 20. The front is located in the direction pointed by arrow F. In this example, the rear portion of the vehicle body has a first rear color, and the front portion of the vehicle body has a first front color.

[0042] Figure 2 The same motor vehicle 20 is shown with a second color different from the first color. As can be seen, the rear portion of the vehicle body has a second rear color different from the first rear color. Likewise, the front portion of the vehicle body has a second front color different from the first front color depending on the second color.

[0043] The principle of the transition of a zone Z of the body of the motor vehicle 20 from a first colour to a second colour (both during daytime and nighttime operation) will be described below. The zone Z may cover a part or even the entire body of the vehicle 20 .

[0044] To allow the color of region Z to change, the region is Figure 2 The structure S shown in FIG. 2 is covered. The structure S is, for example, adhesively bonded to a zone Z of the body of the motor vehicle 20. Alternatively, the structure S can be attached to the zone Z mechanically.

[0045] Figure 3 is an exploded schematic diagram of structure S. Structure 1 is a multilayer structure consisting of a stack of a flexible substrate 2, a metal layer 3, an electrochromic organic material layer 4 and a transparent waveguide 5. The color of region Z is determined by the electrochromic organic material layer 4 as explained below.

[0046] For example, the flexible substrate is made of silicone, polycarbonate or PMMA.The substrate 2 has a thickness of, for example, 500 micrometers.

[0047] The metal layer 3 is defined by a first face F1 and a second face F2. The first face F1 is in contact with the face F0 of the flexible substrate 2. For example, the metal layer 3 may be made of aluminum, chromium or gold. The thickness of the metal layer 3 is, for example, between 70 nm and 100 nm.

[0048] The electrochromic organic material layer 4 is defined by the third face F3 and the fourth face F4. Electrochromic refers to a material that changes color when a voltage is applied thereto for a short time. After the voltage is applied, the material retains the new color. The third face F3 is in contact with the second face F2. For example, the electrochromic organic material is PEDOT (poly (3,4-ethylenedioxythiophene)). Other examples of electrochromic materials that can be used are 2-alkylthieno [3,4-b] thiophene (T34bT), PMMA or polycarbonate. The electrochromic organic material layer 4 has a thickness, for example, between 75nm and 300nm.

[0049] The transparent waveguide 5 has the function of lighting the electrochromic organic material layer 4 at night. The transparent waveguide 5 is in contact with the fourth face F4 through the fifth face F5. For this purpose, an illumination light source 8 for the waveguide 5 is provided to illuminate the waveguide 5 at night or once the ambient lighting reaches a minimum threshold.

[0050] The transparent waveguide 5 and the illumination light source 8 are mechanically attached to the electrochromic organic material layer 4 , for example at the edge of the structure S.

[0051] The transparent waveguide 5 is, for example, a transparent film with a typical thickness of 50 microns and comprising microstructures. In this case, the illumination source 8 for illuminating the waveguide 5 consists of a row of light-emitting diodes positioned along one edge of the transparent film. The density of the microstructures increases with the distance from the light-emitting diodes so as to diffuse the light evenly through the transparent film. The transparent film can be made of polycarbonate, PMMA (polymethyl methacrylate), PET (polyethylene terephthalate) or TPU (thermoplastic polyurethane). When irradiated with 1000 cd / m 2 When the LED is lit, the transparent film can show a brightness of 100cd / m 2 With 100cd / m 2 For example, a transparent film from Azumo Technologies can be used.

[0052] In the first embodiment, the region Z is monochromatic. In this case, the electrochromic organic material layer 4 has a uniform thickness.

[0053] The following describes the manner in which the electrochromic organic material layer 4 produces the color perceived by the observer. The electrochromic organic material layer 4 acts as a Fabry-Perot cavity formed by the first face F1 and the second face F2. The cavity produces interference of a given wavelength from the ambient light it receives. This interference causes multiple reflections of colored light rays propagating in the opposite direction to the light rays constituting the ambient light. Therefore, unlike absorption phenomena when using pigments or dyes, the electrochromic organic material layer 4 produces coloring of the region Z for the observer through interference phenomena.

[0054] The thickness of the electrochromic organic material layer 4 has an effect on the color perceived by the observer. Figure 4 Schematically, a PEDOT layer with a thickness e1 equal to 800 nm produces red with a wavelength λ1, a PEDOT layer with a thickness e2 equal to 600 nm produces green with a wavelength λ2, and a PEDOT layer with a thickness e3 equal to 500 nm produces blue with a wavelength λ3.

[0055] During the day, the ambient light received by the electrochromic organic material layer is sunlight. At night or in darkness, the ambient light is low, so that the illumination light source 8 of the waveguide 5 is turned on to illuminate the waveguide 5, and thus illuminate the electrochromic organic material layer 4.

[0056] The manner in which the color is changed in area Z is described below.

[0057] like Figure 5 As shown, the electrochromic organic material layer 4 is encapsulated in an electrolyte layer 9, and the first electrode 6a and the second electrode 6b are connected to the electrolyte layer. For example, the electrolyte layer is an aqueous solution of sodium dodecylbenzene sulfonate (NaDBS). The first electrode 6a and the second electrode 6b are encapsulated and arranged in a manner similar to a liquid crystal sheet. Electrodes 6a, 6b are connected to a low-voltage battery for powering them, and are connected to an electronic board, which is connected to the electrical network of the vehicle. The electronic board makes it possible to control the application of a bias voltage between the first electrode and the second electrode and change the voltage according to the desired color.

[0058] Due to its electrochromic properties, the electrochromic organic material layer 4 changes color when a bias voltage is applied. A table showing the correspondence between the desired color and the voltage applied between the first electrode 6a and the second electrode 6b makes it possible to control the color change of the region Z by voltage. The correspondence table depends on the material of the electrochromic organic material layer 4. For example, the bias voltage varies between a minimum voltage of -10 volts and a maximum voltage of +10 volts.

[0059] For example, if the electrochromic organic material layer 4 is a PEDOT layer with a thickness of 600 nm, without polarization, the layer appears green. After a voltage of 1 volt is applied to the PEDOT layer, the layer appears red. After a voltage of 10 volts is applied to the PEDOT layer, the layer appears black. After a voltage of -1 volt is applied to the PEDOT layer, the layer appears red.

[0060] Alternatively, the electrochromic organic material layer 4 is constructed into N elements. For example, the electrochromic organic material layer 4 is constructed into a matrix of N pixels. Each of the N pixels is encapsulated in an electrolyte solution or gel, and a pair of electrodes is connected to the electrolyte solution or gel, which is designed to bias the corresponding pixel with a voltage. N pixels are encapsulated and arranged, and these electrode pairs are arranged on each pixel in a manner similar to a liquid crystal sheet.

[0061] In a second embodiment, the region Z is intended for displaying a pattern, such as a logo or an expression. Therefore, the region Z is multi-colored. The electrochromic organic material layer 4 is then structured into N elements. For example, the electrochromic organic material layer 4 is structured into a matrix of N pixels. Since the electrochromic organic material layer 4 is made of a single material, the thickness of the N pixels varies between the pixels in such a way that the color they produce is adjusted when the electrochromic organic material layer 4 is not biased by a voltage. Figure 6An example of a portion of a corresponding structure 3 is shown, with four pixels P1 , P2 , P3 and P4 of different thicknesses.

[0062] Advantageously, each of the N pixels is encapsulated in an electrolyte solution or gel to which a pair of electrodes is connected, the pair of electrodes being designed to voltage bias the corresponding pixel. The N pixels are encapsulated and arranged, and the electrode pairs are arranged on each pixel in a manner similar to a liquid crystal sheet. This set of N pairs of electrodes is connected to a low-voltage battery and to an electronic board that is connected to the electrical network of the vehicle. The electronic board makes it possible to control the voltage by changing the voltage across the terminals of each pair of electrodes according to the desired color. A table showing the correspondence between the desired color and the voltage at the terminals of a pair of electrodes to be applied makes it possible to control the change of the color of the pixels in the region Z by voltage. For example, the voltage at the terminals of a pair of electrodes varies between a minimum voltage of -10 volts and a maximum voltage of +10 volts.

[0063] A first aspect of the invention relates to a module 10 comprising a structure 1, an illumination source 8 for illuminating a waveguide 5, and a measuring photodetector 7 for measuring the ambient light flux. Figure 5 Module 10 is shown in FIG.

[0064] A measuring photodetector 7 is provided to measure the light flux surrounding the structure S in order to determine whether the structure receives sufficient light to produce a colour by interference as described above.

[0065] The measuring photodetector 7 is, for example, a photodiode placed in the centre of the zone Z. Advantageously, the measuring photodetector 7 is placed on a substantially horizontal surface of the motor vehicle 20 .

[0066] Figure 7 The operation of the module 10 during the day is shown. If the ambient light flux measured by the measuring photodetector 7 is above the threshold value F seuil , the illumination source 8 remains off and the coloring of the module 10 is due to Figure 7 Arrow L in J The interference caused by sunlight is represented by the threshold F. seuil The brightness of area Z generated by reflecting the received ambient light flux can be 200cd / m 2 To 500cd / m 2 Pixel P p and P q Therefore, the colored light L is reflected separately pJ and L qJ .

[0067] Figure 8The operation of the module 10 is shown at night, or more generally, immediately when the ambient light is no longer sufficient to make the zone Z visible. As soon as the ambient light flux measured by the measuring photodetector falls below the threshold F seuil , the illumination light source 8 of the transparent waveguide 5 is activated and illuminates the transparent waveguide 5. Figure 8 Arrow L in N This illumination is schematically shown. The coloring of the module 10 is due to the light from the transparent waveguide 5 illuminated by the illumination source 8 and incident on the pixel P p and P q The interference of light on these pixels and the Figure 8 Arrow L in S Indicates. Pixel P p and P q Therefore, the colored light L is reflected separately pS and L qS .

[0068] Therefore, since the electrochromic organic material layer 4 is illuminated by the illuminated transparent waveguide 5, the color of the area Z is visible also at night.

[0069] Advantageously, the module 10 according to the invention also comprises a proximity sensor 11. The proximity sensor 11 makes it possible, for example, to detect pedestrians or other vehicles in the vicinity of the motor vehicle 20.

[0070] For example, the proximity sensor 11 is placed on the transparent waveguide 5. In particular, the proximity sensor 11 may be placed at the rear of the motor vehicle 20 in this example.

[0071] Typically, the proximity sensor 11 is placed on a substantially vertical surface of the motor vehicle 20 .

[0072] When the proximity sensor 11 generates a signal triggered by detecting a pedestrian or another vehicle, a change in the color of the zone Z can be implemented to improve the visibility of the zone Z. The zone Z can effectively play a signaling role. The signal generated by the proximity sensor 11 is transmitted to an electronic board, for example, which controls one or more changes in the bias voltage in order to change the color of all or part of the zone Z.

[0073] For example, the zone Z is a door of the motor vehicle 20 .

[0074] In another example, zone Z is located on the grille of the motor vehicle 20 .

[0075] Another aspect of the invention relates to a plurality of colored zones Z1, Z2, Z3 of the body of a motor vehicle 20. i …Z N These colors can be controlled in a manner similar to the control of the colors of zone Z described above.

[0076] For example, multiple colored areas Z1, Z2...Z N This includes one or more portions of the body of the motor vehicle 20 , such as a door, or a logo on a grille, or even the entire motor vehicle 20 .

[0077] Multiple colored areas Z1, Z2, Z N Each of which is covered with an adhesive bond or mechanically attached to a corresponding colored region Z i The corresponding structures S1, S2, S N Each corresponding structure S i It is a multi-layer structure similar to the structure S described above.

[0078] Each corresponding structure S i The electrochromic organic material layer 4i either has a constant thickness and is encapsulated in an electrolyte layer to which a pair of electrodes are connected, or is constructed into N pixels, each pixel is encapsulated in an electrolyte layer, and each pixel is connected to a pair of electrodes. In both cases, the electrodes are powered by a plurality of low-voltage batteries and connected to an on-board master-slave electronic system, which is connected to the electrical network of the vehicle 20.

[0079] The master-slave electronic system allows simultaneous or selective control of different colored zones Z i The color change of a single structure S i or multiple structures S1, S2, S N The corresponding structure of the subgroup {S α ,..S γ The master-slave electronic system may, for example, receive instructions sent by a user from the dashboard of the motor vehicle 20 .

[0080] Thus, the present invention enables the exterior of a vehicle to be customized by controlling the color change of different areas of the vehicle body by applying a low bias voltage in the different areas.

Claims

1. A colored module (10), comprising: - a structure (S), the structure comprising: - a flexible substrate (2), a metal layer (3) delimited by a first face (F1) and a second face (F2), the first face (F1) being in contact with the face (F0) of the flexible substrate, - a layer of electrochromic organic material (4) delimited by a third face (F3) and a fourth face (F4), the third face (F3) being in contact with the second face (F2), - a transparent waveguide (5) in contact with the fourth face (F4), - at least one pair of electrodes (6) connected to the electrochromic organic material layer (4), - a measuring photodetector (7) for measuring the ambient light flux, - an illumination light source (8) for illuminating the transparent waveguide (5) when the ambient light flux is below a threshold value.

2. The colored module (10) according to claim 1, wherein: - the electrochromic organic material layer (4) is constructed into N elements, at least two of the N elements having different thicknesses, The at least one pair of electrodes comprises N pairs of electrodes, each pair of the N pairs of electrodes being connected to an edge of a corresponding element of the N elements.

3. The colored module (10) according to any one of claims 1 and 2, wherein: The electrochromic organic material (4) is PEDOT.

4. The colored module (10) according to one of the preceding claims, wherein The flexible substrate (2) is made of silicone, polycarbonate or PMMA.

5. The colored module (10) according to one of the preceding claims, wherein The transparent waveguide (5) is a transparent film comprising a microstructure.

6. The colored module (10) according to one of the preceding claims, wherein: The structure (1) has a thickness of 50 micrometers.

7. The colored module (10) according to one of the preceding claims, further comprising a proximity sensor (11).

8. A motor vehicle comprising a module (10) as claimed in one of the preceding claims.

9. A motor vehicle as claimed in claim 10, wherein: The module (10) is attached to a door of the motor vehicle.

10. The motor vehicle of claim 10, wherein: The module (10) is attached to the grille of the motor vehicle.

11. A method for changing the color of a module (10) as claimed in any one of claims 1 to 9, the method comprising the following steps: - a step (E0) of measuring the ambient light flux by means of the photodetector (7), - a step (E1) of illuminating the transparent waveguide (5) by the illumination light source (8) if the measured ambient light flux is below the threshold value, - A step (E2) of applying a voltage between a lowest voltage of -10 V and a highest voltage of +10 V between the electrodes in the pair of electrodes.

12. The method for changing the color of the module according to claim 7 as claimed in claim 11, wherein: The voltage applied in this step (E2) depends on the signal received by the proximity sensor (11).

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