Signal transmitter for a vehicle, comprising a microlens array for projecting signals of the vehicle onto a roadway

Abstract

The invention relates to a signal transmitter (1) for a vehicle (20), comprising an image generating device (2) for generating images and a first microlens array (11) having first lenses (21) for projecting the images onto a surface in the surroundings of the vehicle (20), said images reproducing a signal of the vehicle (20).

Description

[0001] Signal generator for a vehicle with a microlens array for projecting signals from the vehicle onto a roadway

[0002] The invention relates to a signal generator for a vehicle and a method for producing a signal generator.

[0003] In general, signals emitted by a vehicle's signaling device can increase road safety. The more easily a signal indicating a vehicle's direction of travel is recognizable to other road users, the greater the safety for the vehicle's driver and other road users.

[0004] A signal generator for a vehicle is proposed. The signal generator has an image generation device for generating images and a first microlens array with first lenses for projecting the images onto a surface in the vehicle's surroundings. The surface can be, for example, a surface of a roadway on which the vehicle is located or a surface of a vehicle traveling ahead. The images reproduce a signal from the vehicle. The signal is preferably suitable for informing, in particular warning, another road user. Thus, the signal can describe a condition of the vehicle. If, for example, a drive unit of the vehicle malfunctions in a breakdown situation, the signal can describe this breakdown situation. If the vehicle performs an emergency braking maneuver, the signal can describe the emergency braking maneuver.In this case, the signal may be formed as a red surface projected onto the roadway using the first microlens array.

[0005] Because the images can be projected onto the surface using the first microlens array, the signal is more easily visible to other road users than is possible with a conventional signal device, such as a turn signal mounted on the vehicle. This increases vehicle safety.

[0006] The first microlens array is configured to project the images onto the surface surrounding the vehicle, in particular the roadway. For this purpose, the image generating device, in particular elements of the image generating device, are arranged relative to the first lenses such that the images can be projected onto the roadway using the first lenses when the signal generator is attached to the vehicle. In a particular embodiment, first optical axes of the first lenses are directed onto the roadway, in particular when the signal generator is attached to the vehicle. The signal generator preferably has a housing with fastening elements for fastening the signal generator to the vehicle. In this case, shapes of the fastening elements specify a position of the first optical axes relative to the roadway when the signal generator is attached to the vehicle.

[0007] The first lenses are preferably arranged at equal intervals within a plane. This makes it possible to project the images onto the roadway in predetermined relative positions. The distances between the first lenses are preferably constant in two extension directions of the first microlens array. This simplifies control of the signal generator. In particular, the first lenses can be arranged in a matrix, i.e., in columns and rows. It is also possible for the first lenses to be arranged hexagonally relative to one another in the plane. This makes it possible to reduce the installation space of the first microlens array. According to an advantageous embodiment, the first lenses can also have a rectangular base area.

[0008] In an advantageous embodiment, the vehicle's signal indicates the vehicle's direction of travel. In this embodiment, the images projected onto the roadway can, for example, represent an arrow indicating the vehicle's direction of travel. The signal generator can thus be used as a supplement to a direction indicator attached to the vehicle. Especially in adverse weather conditions such as fog or rain, the signal can allow other road users to recognize that the vehicle is changing direction.

[0009] In an advantageous embodiment, the image generation device has a second microlens array with second lenses and a slide plane with slide structures. In this embodiment, the slide plane is arranged between the first microlens array and the second microlens array. The slide plane preferably runs parallel to the plane within which the first lenses are arranged. The slide structures have image information for generating the images. The slide structures are arranged next to one another in the slide plane. The second lenses are preferably designed to direct light rays entering the second lenses onto the slide structures. This makes it possible to achieve the strongest possible illumination of the slide structures. The focal points of the second lenses are preferably located near the slide plane, preferably at a distance of approximately 0 to 100 pm from the slide plane. In a further variant, the focal points of the second lenses can be located in the first lenses.The light beams preferably strike the second lenses approximately parallel. For this purpose, the signal generator preferably has one or more collimators. A light source for generating the light beams is arranged in front of the collimator. The collimator is arranged between the light source and the second lenses. The light source preferably comprises one or more light-emitting diodes.

[0010] Advantageously, the focal points of the first lenses lie in the slide plane. This allows light rays that strike an exemplary lens of the first lenses from a single point of an exemplary slide structure in multiple directions to emerge from the exemplary lens parallel to one another. This allows a sharp image to be produced, particularly due to the miniaturization of the exemplary lens.

[0011] In an advantageous embodiment, the slide structures are designed such that the projected images at least partially overlap, preferably on the surface, in particular on the roadway. The slide structures can each be designed in the form of a set of pixels. The pixels of the respective set are preferably each related to a pixel of pixels of an overall image. The overall image is created by superimposing the images projected onto the surface, in particular onto the roadway, and describes the signal. The pixels of the slide structures can, for example, be designed in the form of openings in a chromium layer of the slide plane.

[0012] The sets of pixels preferably differ from one another in such a way that pixels from different sets of pixels, each of which can be assigned to the same pixel of the overall image, can be imaged on a common area, in particular a common point, of the surface, in particular the roadway, using the first lenses. For this purpose, those pixels of the different sets that are assigned to the same pixel of the overall image, hereinafter also referred to as assigned pixels, have a different position relative to a center of the respective slide structure.

[0013] Two or more of the assigned pixels can be projected onto the common area of ​​the surface, especially the roadway, using the first lenses. The more assigned pixels projected onto the common area, the brighter the pixel of the overall image to which the assigned pixels are assigned appears. The brighter the overall image appears on the roadway, the greater the safety that can be achieved with the signal device.

[0014] In a further embodiment, the image generation device has a plurality of independently switchable light sources. The light sources are each assigned to at least one pair of lenses and arranged at different locations relative to the first microarray. Each pair comprises one lens of the first lenses and one lens of the second lenses. In this embodiment, the slide structures are designed such that the images can be projected onto different areas of the surface, in particular the roadway, at least partially depending on the switched light sources. The images can partially overlap.

[0015] In order to project a respective part of the images onto a respective area of ​​the areas, a respective set of light sources can preferably be switched on. The respective set of switched-on light sources can comprise a single light source or preferably a plurality of switched-on light sources. Light generated using the respective set of switched-on light sources preferably detects a plurality of the first lenses. As a result, a respective set of a plurality of slide structures can be illuminated and the images that can be displayed using the respective illuminated slide structures can be projected onto the respective area of ​​the roadway. For this purpose, the respective illuminated slide structures can be designed such that the images projected onto the roadway by the respective illuminated slide structures at least partially overlap in the respective area.For each set of illuminated slide structures, this superimposition can generate a further overall image on the respective section of the roadway. The light sources can be switched independently of one another. This allows the images to be projected onto the roadway independently of one another. In particular, the light sources can be switched sequentially in such a way that the images are projected one after the other onto the different areas, one after the other, in order to project one of the further overall images onto the roadway one after the other. In this case, the further overall images can also be identical, so that the identical further overall image "wanders" for an observer on the roadway.

[0016] In an advantageous embodiment, the signal generator has a first carrier. In this embodiment, the first microlens array is arranged on the first carrier. In one variant of this embodiment, the first carrier and the lenses of the first microlens array can be made of the same material. In a further variant of this embodiment, the first carrier can be made of a first material and the first lenses can be made of a second material. In this variant, the first material is preferably a harder polymer than the second material. The first material can be cured, for example, using UV light.Compared to a variant in which the first microlens array is manufactured using polymer-on-glass technology, the variant in which the first carrier and the first lenses are made of the same material allows the first microlens array to be manufactured using an injection molding process. This can reduce the cost of manufacturing the signal generator.

[0017] The first carrier can have a thickness between 400 pm and 1200 pm, preferably between 500 pm and 700 pm. This simplifies the production of the first microlens array by injection molding or compression molding.

[0018] Alternatively or additionally, the signal generator may have a second carrier, and the second microlens array may be arranged on the second carrier, and the second carrier and the lenses of the second microlens array may be made of the same material. This allows the second microlens array to be manufactured using an injection molding process, thus reducing the complexity of manufacturing the signal generator. The second carrier may have a thickness between 400 pm and 3000 pm, preferably between 500 pm and 700 pm.

[0019] In a further advantageous embodiment, the first microlens array and the first carrier are formed as a single piece. Alternatively or additionally, the second microlens array and the second carrier are formed as a single piece. This allows the first microlens array and the second microlens array, respectively, to be manufactured in a single injection-molding step. This further reduces the manufacturing effort for the signal generator.

[0020] The first microlens array is preferably a thermoplastic polymer. Alternatively or additionally, the second microlens array can be a thermoplastic polymer. The respective thermoplastic polymer can comprise a polymethyl methacrylate (PMMA), a cycloolefin polymer (COP), a polycarbonate (PC), or an optical silicone.

[0021] According to one possible variant, the image generation device can comprise a display array with multiple displays and a mirror array with multiple mirrors. In this variant, the displays are each assigned to at least one mirror of the mirror array, and the mirrors are each assigned to at least one lens of the first microlens array. The mirrors are preferably adjustable. In particular, the mirrors and the displays can be arranged on a microchip. The microchip can be configured to control the alignment of the mirrors.

[0022] Furthermore, a method for producing a signal generator according to one of the variants described above is proposed. The method comprises the following steps. In a first step, the first microlens array is produced. In a second step, the second microlens array is produced. The microlens arrays can be produced by injection molding, hot stamping, UV replication, a nano-imprint, or a wet embossing process. In a third step, the slide plane is attached to the second microlens array, preferably with an additional carrier. In a fourth step, the first microlens array is joined to the second microlens array.

[0023] Furthermore, the use of a signal generator according to one of the variants described above for projecting images onto the surrounding surface is proposed. The use comprises the following steps: The images are generated using the image generation device. The images are then projected onto the surface, in particular the roadway, using the first microlens array. The images reproduce the vehicle's signal. In particular, the signal generator can be used such that multiple signals are projected sequentially onto the surface, in particular the roadway.

[0024] Preferred embodiments are explained in more detail with reference to the following figures. Here, schematically

[0025] Figure 1 is a side view of a signal generator with a first microlens array and an image generating device;

[0026] Figure 2 shows a vehicle with the signal generator shown in Figure 1;

[0027] Figure 3 shows the signal generator shown in Figure 1 with a second microlens array and a slide plane with slide structures;

[0028] Figure 4 shows the slide plane shown in Figure 3 in a plan view;

[0029] Figure 5 shows the first microlens array shown in Figure 1 in a plan view;

[0030] Figure 6 shows the second microlens array shown in Figure 3 in a plan view;

[0031] Figure 7 shows the image forming device shown in Figure 1 with a light source and a collimator;

[0032] Figure 8 shows a signal projected onto a roadway using the signal generator shown in Figure 1;

[0033] Figure 9 shows a further variant of the signal generator shown in Figure 1 with several light sources and lenses of the first microarray and the second microarray assigned to one of the light sources;

[0034] Figure 10 shows another variant of the signal generator shown in Fig. 9 with several collimators.

[0035] Fig. 1 shows a signal generator 1 for a vehicle 20. The signal generator 1 has an image generation device 2 for generating images and a first microlens array 11 for projecting the images onto a roadway 3 shown in Fig. 7. The images represent a signal from the vehicle. The image generation device 2 preferably comprises a plurality of image generators, for example a first image generator 2.1, a second image generator 2.2, and a third image generator 2.3. The first microlens array 11 has first lenses 21. The first lenses 21 are arranged on a first carrier 31. The respective image generator 2.1, 2.2, 2.3 is assigned to at least one of the first lenses 21.

[0036] Fig. 2 shows the signal generator 1 in a state installed in the vehicle 20. The signal generator 1 preferably has at least one fastening element 29 for fastening the signal generator 1 to a body of the vehicle 20. In the installed state of the signal generator 1, the fastening element 29 specifies, in particular, a position of the signal generator 1 relative to the body. This specified position also specifies a position of first optical axes of the first lenses 21 relative to the roadway 3. As a result, the images can be projected onto the roadway 3 using the first microlens array 11.

[0037] Fig. 3 shows an embodiment in which the image generation device 2 has a second microlens array 12 with second lenses 22 and a slide plane 100 with slide structures, such as a first slide structure 101.1, a second slide structure 101.2 and a third slide structure 101.3. The slide plane 100 is arranged between the first microlens array 11 and the second microlens array 12. In the embodiment shown in Fig. 3, the first image generator 2.1 comprises the first slide structure 101.1 and that lens of the second lenses 22 which is arranged closest to the first slide structure 101.1. The same applies analogously to the second and third image generators 2.2, 2.3. Centers of curvature of the first lenses 21 and centers of curvature of the second lenses 22, which are each arranged in pairs opposite one another with respect to the slide plane 100, each define in pairs a respective optical axis and form a respective projection channel.

[0038] Fig. 4 shows the slide plane 100 in view AA sketched in Fig. 3. In this view, further slide structures 101.4, 101.5, 101.6, 101.7, 101.8, 101.9 of the slide plane 100 can be seen. The slide structures 101.1, 101.2, 101.3, 101.4, 101.5, 101.6, 101.7, 101.8, and 101.9 are collectively referred to below as slide structures 101. The slide structures 101 contain image information for generating the images. For this purpose, the slide plane 100 can be made of a chromium layer. The image information of the slide structures 101 can be formed by openings in the chromium layer. In other words, the slide structures 101 are formed by an arrangement of the openings relative to one another in the slide plane 100. For the sake of clarity, the openings and also a respective two-dimensional structure of the first microlens array 11, the second microlens array 12, and the slide plane 100 are not shown in Fig. 3.

[0039] Fig. 5 shows the first microlens array 11 in view AA. Fig. 6 shows the second microlens array 12 in view BB. It goes without saying that the number of lenses of nine for the two microlens arrays 11, 12, as shown in the figures, is only exemplary. Practically, the microlens arrays 11, 12 each have a number of lenses in a range of approximately 100 to 150.

[0040] With the aid of the slide structures 101, the images can be generated by illuminating the slide structures 101 using at least one light source 70 of the image generation device 2, shown in Fig. 7. Light rays emitted by the light source 70 preferably pass through a collimator 71 of the image generation device 2 and, from the collimator 71, strike the image generators 2.1, 2.2 and 2.3. The first lenses 21 project the generated images onto the roadway 3, thereby generating an overall image 80 on the roadway 3. The overall image 80 is shown in Fig. 7 for illustrative purposes with a height relative to the roadway 3 in order to make it visible in Fig. 7. It goes without saying that the overall image 80 has no height.

[0041] As already described above, the slide structures 101 can each be considered a respective set of pixels. In this view, the openings form bright, particularly white, pixels of the respective set. At those locations where the respective slide structure of the slide structures 101 does not have an opening, the respective slide structure, i.e., the respective set of pixels, has a dark, particularly black, pixel.

[0042] The slide structures 101 are preferably each configured such that a respective pixel of the respective set is assigned to a respective identical pixel of the overall image 80, which results from a superposition of the images. In other words, a pixel of the respective slide structure 101.1, 101.2, 101.3, 101.4, 101.5, 101.6, 101.7, 101.8, or 101.9 is assigned to the respective pixel of the overall image 80. Collectively, the respective pixels of the slide structures 101 that are assigned to the respective identical pixel of the overall image 80 can be referred to as a respective set of assigned pixels.

[0043] In particular, the respective set of assigned pixels can be imaged in a respective common area of ​​the roadway 3 using the first lenses 21. For this purpose, the pixels of the respective set of assigned pixels each have a different position relative to a center point 102.1, 102.2, 102.3, 102.4, 102.5, 102.6, 102.7, 102.8, or 102.9 of the respective diastructure 101.1, 101.2, 101.3, 101.4, 101.5, 101.6, 101.7, 101.8, or 101.9.

[0044] Fig. 4 shows, by way of example, a first set of assigned pixels of the sets of assigned pixels. The first set of assigned pixels comprises a pixel 103.1, 103.2, 103.3, 103.4, 103.5, 103.6, 103.7, 103.8, or 103.9 of the respective slide structure 101.1, 101.2, 101.3, 101.4, 101.5, 101.6, 101.7, 101.8, or 101.9. The pixels of the first set are assigned to a first pixel 801 of the overall image 80, which is shown in Fig. 8. Furthermore, the pixels of the first set can be projected onto a first common area 811 of the roadway 3 using the first lenses 21. In an analogous manner, further sets of the assigned pixels of the sets of assigned pixels can be projected onto further regions 820 of the roadway 3 using the first microlens array 11. The overall image 80 can preferably be displayed by imaging the first pixel 801 and further pixels 810 on the roadway 3.The further sets of assigned pixels are each assigned to one of the further pixels 810. For the sake of clarity, the further regions 820 are not fully provided with reference numerals in Fig. 8. The further regions 820 are shown as rectangles and each delimit one of the further pixels 810.

[0045] In addition to the first set of pixels shown in Fig. 4, the pixels of the diastructures 101 also have the additional sets of associated pixels. For clarity, however, the additional sets of associated pixels are not shown in Fig. 4.

[0046] As can be seen in Fig. 8, the overall image 80 represents an arrow pointing to the right. The overall image 80, and in the example shown in Fig. 8 the arrow, represent the signal of the vehicle 20. Fig. 8 shows in particular a variant in which the signal of the vehicle 20 indicates a direction of travel of the vehicle 20. In the variant shown in Fig. 8, the signal generator 1 projects the images onto a section of the roadway located in front of the vehicle 20. If the arrow points to the right, the signal generator 1 preferably projects the images onto a first section of the roadway located in front of the vehicle 20 and to the right of a center line of a current lane of the vehicle 20. If the arrow points to the left, the signal generator 1 preferably projects the images onto a second section of the roadway located in front of the vehicle 20 and to the left of the center line of the current lane of the vehicle 20.

[0047] Fig. 9 shows an embodiment of the signal generator 1 from the view CC shown in Fig. 1 and Fig. 2, i.e. from above. In this embodiment, the image generation device 2 has a plurality of independently switchable light sources, for example a first light source 91, a second light source 92 and a third light source 93. The light sources are each assigned to at least one pair of lenses. The respective pair comprises one lens of the first lenses 21 and one lens of the second lenses 22. In the embodiment shown in Fig. 9, the image generation device 2 has, instead of the slide structures 101, further slide structures which lie in the slide plane 100. Analogous to the slide structures 101, the further slide structures have image information for generating the images. In this variant, the images comprise first, second and third images.

[0048] The additional slide structures are designed such that the images can be projected onto different areas of the roadway 3, at least partially depending on the switched light sources 91, 92, 93. The roadway 3 is additionally marked in Fig. 9 by a road edge 94. The additional slide structures preferably comprise at least first slide structures 201.1, second slide structures 201.2, and third slide structures 201.3.

[0049] The first slide structures 201.1 can be illuminated by first light beams generated by the first light source 91. Furthermore, the first slide structures 201.1 are designed such that the first images generated by the first slide structures 201.1 can be projected onto a first region 9.1 of the roadway 3 using a first part of the first lenses 21. The first part of the first lenses 21 comprises the lower three lenses of the first lenses 21 shown in Fig. 9. According to one variant, the first slide structures 201.1 can be designed similarly to the slide structures 101. The first slide structures 201.1 differ from the slide structures 101 in the variant shown in Fig. 9 in such a way that a position of the respective pixel of the first slide structures 201.1 is offset within the slide plane 100 compared to a corresponding pixel of the slide structures 101 such that a first arrow 10.1 points to the first region 9.1 is projected when the first slide structures are illuminated by the first light rays.

[0050] The second slide structures 201.2 can be illuminated by second light beams generated by the second light source 92. Furthermore, the second slide structures 201.2 are designed such that the second images generated by the second slide structures 201.2 can be projected onto a second region 9.2 of the roadway 3 using a second part of the first lenses 21. The second part of the first lenses 21 comprises the middle three lenses of the first lenses 21 shown in Fig. 9. According to one variant, the second slide structures 201.2 can be designed similarly to the slide structures 101. The second slide structures 201.2 differ from the slide structures 101 in the variant shown in Fig. 9 in such a way that a position of the respective pixel of the second slide structures 201.2 is offset within the slide plane 100 compared to a corresponding pixel of the slide structures 101 such that a second arrow 10.2 points to the second region 9.2 is projected when the second slide structures are illuminated by the second light beams.

[0051] Analogously, the third slide structures 201.3 can be illuminated by third light beams generated by the third light source 93. Furthermore, the third slide structures 201.3 are designed such that the third images generated by the third slide structures 201.3 can be projected onto a third region 9.3 of the roadway 3 using a third part of the first lenses 21. The third part of the first lenses 21 comprises the upper three lenses of the first lenses 21 shown in Fig. 9. According to one variant, the third slide structures 201.3 can be designed similarly to the slide structures 101. The third slide structures 201.3 differ from the slide structures 101 in the variant shown in Fig. 9 in such a way that a position of the respective pixel of the third slide structures 201.3 is offset within the slide plane 100 compared to a corresponding pixel of the slide structures 101 such that a third arrow 10.3 points to the third region 9.3 is projected when the third slide structures are illuminated by the third light rays.

[0052] If the first, second, and third light sources 91, 92, and 93 are switched on sequentially, the first arrow 10.1 appears first, followed by the second arrow 10.2, and then the third arrow 10.3. To an observer, for example, a driver of another vehicle traveling alongside the vehicle 20, it appears as if the arrow shown in Fig. 8 is moving to the right on the roadway. This allows the observer to see the direction of travel more clearly than is possible using the arrow shown in Fig. 8 alone.

[0053] Fig. 10 shows a further variant of the embodiment of the signal generator 1 shown in Fig. 9. Compared to the embodiment shown in Fig. 9, the signal generator 1 has three collimators instead of the single collimator 71, namely a first collimator 71.1, a second collimator 71.2 and a third collimator 71.3. The first collimator 71.1 aligns the first light beams approximately parallel to one another so that they strike the first diastructures 201.1. Analogously, the second collimator 71.2 aligns the second light beams approximately parallel to one another so that they strike the second diastructures 201.2. In a similar way, the third collimator 71.3 aligns the third light beams approximately parallel to one another so that they strike the third diastructures 201.3.

Claims

Patent claims 1. A signal generator (1) for a vehicle (20), comprising an image generating device (2) for generating images and a first microlens array (11) with first lenses (21) for projecting the images onto a surface in an environment of the vehicle (20), wherein the images reproduce a signal of the vehicle (20).

2. Signal generator (1) according to claim 1, wherein the signal of the vehicle (20) indicates a direction of travel of the vehicle (20).

3. Signal generator (1) according to claim 1 or 2, wherein the image generating device (2) has a second microlens array (12) with second lenses (22) and a slide plane (100) with slide structures (101.1, 101.2, 101.3), wherein the slide plane (100) is arranged between the first microlens array (11) and the second microlens array (12) and the slide structures (101.1, 101.2, 101.3) have image information for generating the images.

4. Signal generator (1) according to claim 3, wherein the slide structures (101.1, 101.2, 101.3) are designed such that the projected images at least partially overlap.

5. Signal generator (1) according to claim 3, wherein the image generating device (2) has a plurality of independently switchable light sources (91, 92, 93), wherein the light sources (91, 92, 93) are each assigned to at least one pair of lenses and the respective pair comprises a lens of the first lenses (21) and a lens of the second lenses (22), and the slide structures are designed such that the images can be projected onto different areas of the surface at least partially depending on the switched light sources (91, 92, 93).

6. Signal generator (1) according to one of the preceding claims, wherein the signal generator (1) has a first carrier (31) and the first microlens array (11) is arranged on the first carrier (31) and the first carrier (11) and the first lenses (21) of the first microlens array (11) are made of the same material and / or the signal generator (1) has a second carrier (32) and the second microlens array (12) is arranged on the second carrier (32) and the second carrier (32) and the second lenses (22) of the second microlens array (12) are made of the same material.

7. Signal generator (1) according to claim 5 or 6, wherein the first microlens array (11) and the first carrier (31) are formed in one piece and / or the second microlens array (12) and the second carrier (32) are formed in one piece.

8. Signal generator (1) according to claim 1, wherein the image generating device (2) comprises a display array with a plurality of displays and a mirror array with a plurality of mirrors, wherein the displays are each assigned to at least one mirror of the mirror array and the mirrors are each assigned to at least one lens of the first microlens array and the mirrors are adjustable.

9. A method for producing a signal generator (1) according to one of claims 2 to 8, the method comprising the following steps: - producing the first microlens array (11); - producing the second microlens array (12); - attaching the slide plane (100) to the second microlens array (12), wherein the slide plane (100) comprises slide structures and the slide structures comprise image information for generating the images; - assembling the first microlens array (11) with the second microlens array (12).

10. Use of a signal generator (1) according to one of claims 1 to 9 for projecting the images onto a surface in the surroundings of the vehicle (20), the use comprising the following steps: - generating the images using the image generating device (2); - Projecting the images onto the surface using the first microlens array (11), the images representing a signal from the vehicle (20).

Images