Road surface drawing device

Abstract

A road surface rendering device (10) comprises a plurality of light sources (12) that can be turned on individually, a mask (18) including a plurality of transmission windows (20) respectively illuminated by corresponding light sources (12) among the plurality of light sources (12), partitions (22) that partition a space between the plurality of light sources (12) and the mask (18) into a plurality of divisions each including the light source (12) and the transmission window (20) that correspond to each other, and a common projection lens (16) that projects light transmitted from the plurality of light sources (12) through the respectively corresponding transmission windows (20) onto a road surface.

Description

Technical Field

[0001] The present invention relates to a road surface drawing device.

Background Art

[0002] Conventionally, there is known a drawing device that draws a colored image by projecting each of a plurality of lamp units so as to overlap different color images at the same place in the front (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The above-described drawing device can only display a single type of colored image. Therefore, in order to draw a plurality of types of colored images or display an image in an animation, a plurality of drawing devices must be prepared. Combining a plurality of drawing devices tends to make the entire device large-scale. Alternatively, a drawing device using a digital micromirror device (DMD) is also known, but such a device is expensive and requires complicated control for drawing.

[0005] The present invention has been made in view of such circumstances, and an exemplary object of one aspect thereof is to provide a compact and inexpensive road surface drawing device that draws a plurality of types of images on a road surface.

Means for Solving the Problems

[0006] In order to solve the above problems, a road surface drawing device according to an aspect of the present invention includes a plurality of individually lightable light sources, a mask having a plurality of transmission windows respectively illuminated by corresponding light sources among the plurality of light sources, a partition that partitions the space between the plurality of light sources and the mask into a plurality of sections each having a corresponding light source and a transmission window, and a common projection lens that projects the light transmitted through the corresponding transmission window from each of the plurality of light sources onto the road surface.

[0007] According to this aspect, the road surface drawing device can draw a plurality of types of images on the road surface by individually lighting the light sources to switch the figures represented by the plurality of transmission windows on the mask and projecting them onto the road surface. Since the plurality of sections each having a light source and a transmission window are partitioned by partitions and adjacent to each other, they can be densely arranged as a whole. By using a common projection lens for such a plurality of sections, a compact road surface drawing device can be designed. Further, the road surface drawing device can be realized without using a DMD and can be provided at low cost.

[0008] The plurality of transmission windows of the mask may be arranged on the focal plane of the common projection lens. In this way, by illuminating each transmission window with the corresponding light source, the shape of the figure represented by the transmission window can be projected onto the projection surface through the projection lens.

[0009] The plurality of transmission windows of the mask may be arranged on an inclined surface with respect to the principal plane of the common projection lens. In this way, since the plurality of transmission windows and the projection lens are arranged inclined to each other, it becomes possible to arrange the transmission windows, the projection lens, and the road surface according to the principle of shine-proof. It is possible to reduce the distortion of the projected image on the road surface caused by the non-parallel arrangement (typically orthogonal arrangement) of the transmission window and the road surface.

[0010] The mask may be arranged adjacent to the plurality of light sources so that each transmission window is directly irradiated by the corresponding light source. No optical elements such as reflectors and lenses are arranged between the light source and the mask. This configuration leads to the miniaturization of the road surface drawing device.

[0011] The distance from the light source to the mask may be in the range of 3 mm to 8 mm. In addition to this, or instead of this, the angle formed by two straight lines connecting each of the two ends of the partition from the light source may be in the range of 35 degrees to 65 degrees. In this way, when the light source provides a typical light distribution (for example, Lambertian light distribution), it becomes easy to fill the entire figure represented by the corresponding transmission window without missing any incident light from the light source.

[0012] The plurality of transmission windows may be arranged to face the central portion of the incident surface of the projection lens. In this way, it becomes easier to suppress the distortion of the projected image due to the aberration of the projection lens compared to the case where the transmission window faces the outer peripheral portion. Also, since the plurality of transmission windows are arranged together at the central portion, the road surface drawing device can be miniaturized.

[0013] At least two of the plurality of light sources may be operable to associate the timing of turning on and off with each other. In this way, it is possible to display an animation on the road surface using the associated turning on and off of at least two light sources and at least two transmission windows corresponding to each of these light sources.

[0014] At least two of the plurality of transmission windows may have different shapes and / or colors from each other. In this way, various images can be drawn on the road surface.

Advantages of the Invention

[0015] According to the present invention, it is possible to provide a compact and inexpensive road surface drawing device that can draw a plurality of types of images on the road surface.

Brief Description of the Drawings

[0016]

Figure 1

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Figure 4

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Figure 10

Embodiments for Carrying Out the Invention

[0017] Hereinafter, the present invention will be described with reference to the drawings based on preferred embodiments. The embodiments are illustrative and not restrictive, and not all features and combinations thereof described in the embodiments are necessarily essential to the invention. The same or equivalent components, members, and processes shown in each drawing are denoted by the same reference numerals, and repeated explanations are appropriately omitted. Also, the scales and shapes of the respective parts shown in each figure are set for convenience in order to facilitate the explanation, and are not to be construed restrictively unless otherwise specified. In addition, terms such as "first" and "second" used in this specification or the claims do not represent any order or importance, but are for distinguishing one configuration from another. Also, some members that are not important in explaining the embodiments are omitted from the drawings.

[0018] FIG. 1 is an exploded perspective view of a road surface drawing device according to an embodiment. FIG. 2 is a schematic perspective view of the road surface drawing device according to the embodiment. FIG. 3 is a schematic perspective view showing an enlarged view of a light source and a shade member inside the road surface drawing device according to the embodiment. FIG. 4 is a schematic front view of the shade member shown in FIG. 3. FIG. 5 is a schematic diagram showing an optical system of the road surface drawing device according to the embodiment. FIG. 6 is a schematic perspective view showing a further enlarged part of FIG. 3. FIG. 7(a) shows a figure projected by the road surface drawing device on the projection plane shown in FIG. 5, and FIG. 7(b) shows a figure projected on the road surface by the road surface drawing device.

[0019] As shown in FIG. 1, the road surface drawing device 10 includes a plurality of light sources 12, a shade member 14, and a projection lens 16. Although details will be described later, the shade member 14 includes a mask 18 having a plurality of transmission windows 20 and a partition 22. The road surface drawing device 10 also includes a lens holder 24 that holds the projection lens 16, and a support member 26 that supports the light source 12, the shade member 14, and the lens holder 24.

[0020] In this embodiment, each light source 12 is a light emitting diode (LED), but is not particularly limited, and may be other semiconductor light emitting elements or any other light emitting elements. The light source 12 is mounted on the front surface of a light source mounting substrate 13 facing the projection lens 16, and is arranged relatively densely in close proximity to each other on the light source mounting substrate 13. The light emitting surface of each light source 12 is parallel to the front surface of the light source mounting substrate 13 and is directed toward the projection lens 16. The light source 12 provides a typical light distribution (for example, Lambertian light distribution) that emits light most strongly toward the front with respect to its light emitting surface.

[0021] In this embodiment, as an example, four light sources 12 are provided corresponding to the four transmission windows 20. The four light sources 12 are arranged in a square shape in the vicinity of the optical axis O of the projection lens 16 on the light source mounting substrate 13. The number of light sources 12 is determined according to the number of transmission windows 20 on the mask 18. Any desired number of transmission windows 20 may be provided on the mask 18, and any number of light sources 12 may also be provided according to the number of transmission windows 20.

[0022] The plurality of light sources 12 can be individually lit. As shown in FIG. 3, the light source mounting substrate 13 may be connected to the control substrate 28 by any suitable electrical connection such as connector connection. The plurality of light sources 12 can be individually turned on and off under the control of the control substrate 28. Note that the control substrate 28 may be connected to an external power source (not shown). The light source 12 can be powered from the external power source through the control substrate 28 and the light source mounting substrate 13.

[0023] Each light source 12 emits light of a desired color, such as white light or light of other colors. All or some of the plurality of light sources 12 may emit light of the same color, or all or some of the plurality of light sources 12 may emit light of different colors from each other.

[0024] The mask 18 is disposed between the light source 12 and the projection lens 16 with its back facing the light source 12 side and its front facing the projection lens 16. The mask 18 has a plurality of transmission windows 20 as shown in FIGS. 3 and 4. The mask 18 is a stencil mask in this embodiment, and each transmission window 20 is an opening penetrating from the front surface to the back surface of the mask 18. The transmission window 20 is formed, for example, by punching out from a plate-shaped mask substrate. The mask substrate is formed of, for example, a metal material, but may be formed of a resin material or other suitable materials.

[0025] At least two of the plurality of transmission windows 20 may have different shapes from each other. For example, all the transmission windows 20 may have different shapes from each other. Alternatively, all or some of the plurality of transmission windows 20 may have the same shape.

[0026] The shape of each transmission window 20 represents a figure to be projected onto the road surface, and may be, for example, a symbol such as an arrow or a straight line, or any character or number. As an example, as clearly shown in FIG. 4, one of the upper two transmission windows 20 may be in the shape of a right arrow, and the other may be in the shape of a left arrow. One of the lower two transmission windows 20 may be in the shape of an arrow feather, and the other may be a horizontal line.

[0027] Each of the plurality of transmission windows 20 on the mask 18 is illuminated by a corresponding light source 12 among the plurality of light sources 12. That is, the transmission window 20 and the light source 12 correspond one-to-one, and one light source 12 is provided for each transmission window 20 to illuminate the transmission window 20. As described above, for example, four transmission windows 20 are provided on the mask 18, and these transmission windows 20 are arranged near the projection lens optical axis O on the mask 18.

[0028] The mask 18 is arranged adjacent to the plurality of light sources 12 so that each transmission window 20 is directly irradiated from the corresponding light source 12. Therefore, no optical elements such as reflectors and lenses are arranged between the light source 12 and the mask 18. With this configuration, it is possible to arrange the light source 12 and the mask 18 close to each other, leading to miniaturization of the road surface drawing device 10.

[0029] The distance D from the light source 12 to the mask 18 shown in FIGS. 3 and 5 may be, for example, in the range of 3 mm to 8 mm. If the distance D is less than 3 mm, since the light source 12 is too close to the transmission window 20 of the mask 18, the light from the light source 12 hardly reaches the outer peripheral portion of the transmission window 20 away from the center of the light emitting surface of the light source 12, making it difficult to accurately project the shape of the transmission window 20. On the other hand, if the distance D exceeds 8 mm, since the light source 12 is separated from the mask 18 in the direction of the optical axis O, it leads to an increase in the size of the device in the optical axis direction. Therefore, by setting the distance D in the range of 3 mm to 8 mm, for example, the entire corresponding transmission window 20 can be illuminated with the light from the light source 12 to accurately project the shape of the transmission window 20 onto the road surface, and an increase in the size of the road surface drawing device 10 can be suppressed.

[0030] In addition, the angle α formed by two straight lines connecting both ends of the partition from the light source 12, as shown in FIG. 6, may be in the range of, for example, 35 degrees to 65 degrees. When this angle α is greater than 65 degrees, it is considered that the light source 12 is too close to the transmission window 20 of the mask 18. Further, when this angle α is less than 35 degrees, it is considered that the light source 12 is too far from the transmission window 20 of the mask 18. Therefore, by setting the angle α in the range of, for example, 35 degrees to 65 degrees, the shape of the transmission window 20 can be accurately projected onto the road surface, and the enlargement of the road surface drawing device 10 can be suppressed.

[0031] As shown in FIG. 5, the plurality of transmission windows 20 of the mask 18 are arranged on the focal plane 30 (a plane orthogonal to the optical axis O of the projection lens 16 at the focal position) of the common projection lens 16. In this way, by illuminating each transmission window 20 with the corresponding light source 12, the shape of the figure represented by the transmission window 20 can be projected onto the projection plane 32 through the projection lens 16. On the projection plane 32, as shown in FIG. 7(a), the figure represented by each transmission window 20 is projected with the up-down and left-right reversed positions on the mask 18.

[0032] Referring again to FIGS. 3 and 4, the partition 22 partitions the space between the plurality of light sources 12 and the mask 18 into a plurality of sections. The partition 22 may be fixed to the back surface of the mask 18 and disposed between the light source 12 and the mask 18. In each of the plurality of sections partitioned by the partition 22, a corresponding light source 12 and a transmission window 20 are arranged. That is, one section includes one light source 12 and the corresponding transmission window 20.

[0033] In this embodiment, the partition 22 has a vertical plate 22a and a horizontal plate 22b that are perpendicular to each other at their respective middle portions. The space between the light source 12 and the mask 18 is divided left and right by the vertical plate 22a and up and down by the horizontal plate 22b, and is partitioned into four sections each having a light source 12 and a transmission window 20.

[0034] Partition 22 is a partition wall that prevents light from entering from one section to another section (e.g., an adjacent section). That is, partition 22 blocks the light from each light source 12 from entering a transmission window 20 different from the transmission window 20 corresponding to that light source 12 (e.g., the transmission window 20 of an adjacent section). In order to suppress light reflection, the surface of partition 22 is preferably a low-reflectivity surface or a non-reflective surface, such as being black, roughened, etc.

[0035] Partition 22 is formed of, for example, a metal material, but may be formed of a resin material or other suitable materials. Partition 22 may be formed of the same material as mask 18, or may be formed of different materials.

[0036] Projection lens 16 projects the light transmitted through the corresponding transmission windows 20 from the plurality of light sources 12 onto the road surface. Projection lens 16 is provided as a lens common to the plurality of light sources 12 and the plurality of transmission windows 20. Projection lens 16 may be a compound lens, and may be composed of, for example, three lenses arranged on the optical axis O as shown in FIG. 1. By using projection lens 16 as a compound lens, it is possible to correct aberrations such as chromatic aberration and accurately project the shape of transmission window 20. When emphasizing lower cost, projection lens 16 may be a single lens.

[0037] The plurality of transmission windows 20 (and the plurality of light sources 12) may be arranged to face the central portion of the incident surface of projection lens 16. The central portion of the incident surface of projection lens 16 may be, for example, a region that is 2 / 3 or less, or 1 / 2 or less, or 1 / 3 or less of the projection lens radius centered on the optical axis O. In this way, it becomes easier to suppress the distortion of the projected image due to the aberration of projection lens 16 compared to the case where transmission window 20 faces the outer peripheral portion of projection lens 16. Also, since the plurality of transmission windows 20 are arranged together at the central portion, it is also helpful for miniaturizing the road surface drawing device 10.

[0038] The projection lens 16 is formed of a light-transmissive material such as, for example, a transparent resin or glass. The projection lens 16 is colorless and transparent in this embodiment, but may be colored depending on the desired drawing.

[0039] The lens holder 24 has a cylindrical shape and holds the projection lens 16 therein. By supporting the lens holder 24 by the support member 26, the projection lens 16 and the mask 18 can be positioned. In this example, the lens holder 24 is directly attached to the support member 26, but is not limited thereto, and can take various attachment modes. For example, a bracket to which the lens holder 24 is attached may be provided, and this bracket may be attached to the support member 26.

[0040] The support member 26 not only supports the light source 12, the shade member 14, and the lens holder 24, but is also provided as a heat dissipation member (also called a heat sink) for the light source 12. The light source mounting substrate 13 is fixed to the support member 26 such that the back surface of the light source mounting substrate 13 is in surface contact with the front surface of the support member 26, and the support member 26 is in thermal contact with the light source 12 and the light source mounting substrate 13. A plurality of heat dissipation fins (not shown) extending rearward may be provided on the back surface of the support member 26. The support member 26 is formed of a metal material such as, for example, aluminum or an aluminum alloy, or other high heat conduction materials. The heat generated by the light emission of the light source 12 can be dissipated to the surroundings through the support member 26, preventing the light source 12 and the surrounding components from being overheated.

[0041] The operation of the road surface drawing device 10 according to the embodiment will be described. The light emitted from the light source 12 is shaped according to the shape of the transmission window 20 when passing through the transmission window 20 corresponding to the light source 12. The light beam shaped by the transmission window 20 is projected onto the road surface in front of the road surface drawing device 10 through the projection lens 16. Thus, as shown in FIG. 7(b), the figures represented by the respective transmission windows 20 are drawn in different regions on the road surface. By lighting a specific light source 12 among the plurality of light sources 12 and turning off the other light sources 12, the figure represented by the transmission window 20 corresponding to the lit light source 12 is projected onto the road surface.

[0042] As described above, according to the road surface drawing device 10 according to the embodiment, a plurality of light sources 12 can be individually lit, and a figure represented by the transmission window 20 corresponding to the lit light source 12 can be selectively projected onto the road surface. By turning off this light source 12 and turning on another light source 12, it is possible to switch to another figure represented by the transmission window 20 corresponding to this other light source 12 and project it onto the road surface. In this way, the road surface drawing device 10 can draw a plurality of types of images on the road surface.

[0043] According to the road surface drawing device 10 according to the embodiment, a plurality of sections each having a light source 12 and a transmission window 20 are partitioned by partitions 22 and adjacent to each other, and these can be arranged densely as a whole. By arranging a common projection lens 16 for such a plurality of sections, the road surface drawing device 10 can be designed to be compact.

[0044] The road surface drawing device 10 can be realized without using a DMD and can be provided at low cost.

[0045] In addition, in a drawing device using a DMD, a reflector that reflects light from the light source toward the DMD is provided. In addition, since the operating DMD becomes a considerable heat source, a corresponding cooling configuration such as a heat sink and a cooling fan is required. On the other hand, since the road surface drawing device 10 does not have a DMD, such a reflector is not required. Moreover, the cooling configuration can also be simplified. These factors also help to design the road surface drawing device 10 to be compact and provide it at low cost.

[0046] In a DMD, a large number of mirror elements are mechanically driven, the tilt angle of the reflecting surface of each mirror element is controlled, and thereby the figure to be drawn is changed. In contrast, in the road surface drawing device 10, the figure to be drawn can be switched by selecting the light source 12 to be lit. Since the road surface drawing device 10 does not require mechanical drive for switching the figure to be drawn, the risk of failure is reduced compared to a drawing device using a DMD.

[0047] FIG. 8(a) is an enlarged schematic perspective view showing another example of a light source and a shade member inside the road surface drawing device according to the embodiment, and FIG. 8(b) is a schematic front view of the shade member shown in FIG. 8(a).

[0048] As shown in FIGS. 8(a) and 8(b), the mask 18 has a plurality of transmission windows 20. Each of the plurality of transmission windows 20 on the mask 18 is illuminated by a corresponding light source 12 among the plurality of light sources 12. Also in this example, the space between the plurality of light sources 12 and the mask 18 is partitioned into a plurality of compartments by a partition 22. The partition 22 has a vertical plate 22a and a horizontal plate 22b, and the space between the light source 12 and the mask 18 is divided into left and right by the vertical plate 22a and into upper and lower by the horizontal plate 22b. The partition 22 further has an additional vertical plate 22c, and the lower right compartment among the four compartments is divided into two compartments left and right. A light source 12 and a transmission window 20 are provided in each of these five compartments.

[0049] As an example, one of the two upper transmission windows 20 is formed of two horizontal lines, and the other is formed of a triangle. Each of the three lower transmission windows 20 is formed of a left-facing triangle, a vertical line, and a vertical line. The three lower transmission windows 20 as a whole form a single left-facing arrow. Note that, depending on the figure to be drawn, a plurality of transmission windows 20 may be formed in one compartment, such as the two-line transmission window 20 in the upper left.

[0050] Also in this case, the plurality of light sources 12 can be individually lit, and the figure represented by the transmission window 20 corresponding to the lit light source 12 can be selectively projected onto the road surface.

[0051] In addition, at least two of the plurality of light sources 12 may be operable to associate the timing of turning on and off with each other. In this way, an animation display can be made on the road surface by using the associated turning on and off of at least two light sources 12 and at least two transmission windows 20 corresponding to these light sources 12 respectively.

[0052] For example, by illuminating a plurality of transmission windows 20 arranged on the mask 18 in the order of their arrangement with corresponding light sources 12, the figures represented by these transmission windows 20 can be sequentially displayed on the road surface. For example, by sequentially turning on and off the corresponding light sources 12 for the three lower transmission windows 20 shown in FIGS. 8(a) and 8(b), the arrows represented by these three transmission windows 20 can be sequentially lit on the road surface.

[0053] FIGS. 9(a) to 9(c) are diagrams schematically showing application examples of the road surface drawing device according to the embodiment. The road surface drawing device 10 may be mounted on a vehicle such as an automobile, and may draw on the road surface around the vehicle or other locations around the vehicle. Alternatively, the road surface drawing device 10 may be mounted on a moving body other than a vehicle.

[0054] For example, as shown in FIG. 9(a), the road surface drawing device 10 may be incorporated into the headlamp 101 of the vehicle 100 and draw on the road surface in front of the vehicle or in the vicinity thereof. Alternatively, the road surface drawing device 10 may be incorporated into other vehicle lamps installed at the front of the vehicle, such as fog lamps.

[0055] As another example, as shown in FIG. 9(b), the road surface drawing device 10 may be incorporated into the rear combination lamp 102 or other vehicle lamps installed at the rear of the vehicle, and draw on the road surface behind the vehicle or in the vicinity thereof. Alternatively, as shown in FIG. 9(c), the road surface drawing device 10 may be incorporated into the side mirror 103 and draw on the road surface around the vehicle. The road surface drawing device 10 may be incorporated into vehicle side parts such as courtesy lamps, or other parts of the vehicle, and draw on the road surface around the vehicle or other locations around the vehicle.

[0056] The road surface drawing device 10 may be mounted on, for example, street lamps, traffic signals, signs, buildings, other outdoor fixed structures or devices, and draw on the road surface or other locations around such fixed structures or devices.

[0057] The present invention is not limited to the above-described embodiments and modifications, and it is also possible to combine the embodiments and modifications, or to make further modifications such as various design changes based on the knowledge of those skilled in the art. Embodiments or modifications with such combinations or further modifications are also included in the scope of the present invention. The new embodiments resulting from the above-described embodiments and modifications, and the combinations of the above-described embodiments and modifications and the following modifications have the combined effects of the respective embodiments, modifications, and further modifications.

[0058] (Modification Example 1) FIG. 10 is a schematic diagram showing an optical system of a road surface drawing device according to Modification Example 1. The transmission window 20 on the mask 18 may be disposed on an inclined surface 36 with respect to the main surface 34 of the common projection lens 16. In this way, since the transmission window 20 and the projection lens 16 are disposed to be inclined with respect to each other, it becomes possible to dispose the transmission window 20, the projection lens 16, and the road surface 38 according to the principle of shine proof. It is possible to reduce the distortion of the projected image 40 on the road surface 38 caused by the non-parallel (typically orthogonal) arrangement of the transmission window 20 and the road surface 38.

[0059] (Modification Example 2) In order to color different colors for each projected figure, the emission color of the light source 12 corresponding to a certain transmission window 20 may be different from the emission color of the light source corresponding to another transmission window 20. Alternatively, a certain transmission window 20 may have a color different from that of another transmission window 20. In this case, the transmission window 20 may be covered with a color filter. Alternatively, the mask 18 may be a light-transmissive plate in which regions other than the transmission window 20 are shielded by, for example, a light-shielding film, and the transmission window 20 may be a colorless and transparent region or a colored region having light-transmissivity on this plate.

[0060] (Modification Example 3) Further, a light source 12 capable of emitting light in a plurality of different colors may be provided corresponding to one transmission window 20. In this way, the figure represented by the transmission window 20 can be drawn by switching among a plurality of different colors.

[0061] (Modification Example 4) In the above-described embodiment, one light source 12 is provided corresponding to one transmission window 20. However, for example, in order to increase the amount of light irradiated onto one transmission window 20, a plurality of light sources 12 may be provided corresponding to one transmission window 20.

[0062] (Modification Example 5) The arrangement and shape of the partition 22 depend on the arrangement and shape of the transmission windows 20 on the mask 18. For example, when a total of nine transmission windows 20, three in each of the vertical and horizontal directions, are provided on the mask 18, the partition 22 may have two vertical plates 22a and two horizontal plates 22b.

[0063] Based on the embodiments, the present invention has been described using specific terms. However, the embodiments merely show one aspect of the principle and application of the present invention, and many modifications and changes in arrangement are recognized within the scope that does not depart from the idea of the present invention defined in the claims.

Industrial Applicability

[0064] The present invention can be used in a road surface marking device.

Explanation of Reference Numerals

[0065] 10 Road surface marking device, 12 Light source, 14 Shade member, 16 Projection lens, 18 Mask, 20 Transmission window, 22 Partition.

Claims

1. A plurality of light sources that can be individually lit, A mask having a plurality of transmission windows respectively illuminated by corresponding light sources among the plurality of light sources, A partition that partitions the space between the plurality of light sources and the mask into a plurality of sections each having a corresponding light source and a transmission window, A common projection lens that projects the light transmitted through the corresponding transmission windows from the plurality of light sources onto the road surface, and is provided with, The shape of each transmission window represents a symbol, character or number to be projected onto the road surface, An optical element is not disposed between the light source and the mask, and the mask is disposed adjacent to the plurality of light sources so that each transmission window is directly irradiated from the corresponding light source. A road surface drawing device characterized by this.

2. The plurality of transmission windows of the mask are disposed on a focal plane of the common projection lens. The road surface drawing device according to claim 1, characterized in that.

3. The plurality of transmission windows of the mask are disposed on an inclined surface with respect to a main surface of the common projection lens. The road surface drawing device according to claim 1, characterized in that.

4. The distance from the light source to the mask is in the range of 3 mm to 8 mm. The road surface drawing device according to any one of claims 1 to 3, characterized in that.

5. The angle formed by two straight lines connecting each of both ends of the section from the light source is in the range of 35 degrees to 65 degrees. The road surface drawing device according to any one of claims 1 to 4, characterized in that.

6. The plurality of transmission windows are disposed so as to face the central portion of the incident surface of the projection lens. The road surface drawing device according to any one of claims 1 to 5, characterized in that.

7. At least two of the plurality of light sources are operable to associate the timing of turning off the lights with each other. The road surface drawing device according to any one of claims 1 to 6, characterized in that.

8. At least two of the plurality of transmission windows have different shapes and / or colors from each other. The road surface drawing device according to any one of claims 1 to 7, characterized in that.

Images