Display device for vehicle and vehicle

Abstract

This display device for a vehicle comprises: a first laser diode; a scanning device that reflects and scans a first laser beam emitted from the first laser diode; and a diffusion member having a drawing surface on which the first laser beam emitted from the scanning device is incident. An image drawn on the drawing surface of the diffusion member is observed by an observer.

Description

Vehicle display device and vehicle

[0001] An embodiment relates to a vehicle display device and a vehicle.

[0002] In recent years, CBL (Car Body Lighting) that displays an image on the outer surface of a vehicle has been studied. In CBL, miniaturization and weight reduction are required.

[0003] Japanese Unexamined Patent Application Publication No. 2016-134357

[0004] The embodiment has been made in view of the above problems, and an object thereof is to provide a vehicle display device and a vehicle capable of miniaturization or weight reduction.

[0005] The vehicle display device according to the embodiment includes a first laser diode, a scanning device that reflects and scans the first laser light emitted from the first laser diode, and a diffusion member having a drawing screen on which the first laser light emitted from the scanning device is incident. The image drawn on the drawing screen of the diffusion member is observed by an observer.

[0006] The vehicle according to the embodiment includes the vehicle display device and a light-transmitting portion disposed to face the drawing screen. The image drawn on the drawing screen of the diffusion member is observed by the observer through the light-transmitting portion.

[0007] According to the embodiment, a vehicle display device and a vehicle capable of miniaturization or weight reduction can be realized.

[0008] Figure 1 is a diagram showing a vehicle display device according to the first embodiment. Figure 2A is a diagram showing the positional relationship between the scanning device and the drawing surface. Figure 2B is a diagram showing a control method for the scanning device. Figure 3 is a diagram showing the case when the vehicle display device is damaged. Figure 4 is a diagram showing a vehicle display device according to the first modification of the first embodiment. Figure 5 is a diagram showing a vehicle display device according to the second modification of the first embodiment. Figure 6 is a diagram showing a part of the vehicle display device according to the second embodiment. Figure 7 is a plan view showing a diffusion member in the third embodiment. Figure 8A is a plan view showing the trajectory of the first laser beam in the diffusion member. Figure 8B is a plan view showing the trajectory of the first laser beam in the diffusion member. Figure 9 is a perspective view showing a diffusion member in a modification of the third embodiment. Figure 10 is a diagram showing a vehicle display device according to the fourth embodiment. Figure 11 is a diagram showing a vehicle display device according to the fifth embodiment. Figure 12 is a top view showing a vehicle according to the sixth embodiment. Figure 13A is a diagram showing an example of an image displayed by the display device. Figure 13B is a diagram showing an example of an image displayed by the display device. Figure 13C shows an example of an image displayed by a display device.

[0009] Embodiments and modifications thereof of the present invention will be described below with reference to the drawings. Note that all drawings are schematic and have been emphasized and simplified as appropriate. For example, even for the same components, the positional relationships and dimensional ratios may not strictly match between drawings. Furthermore, in the second and subsequent embodiments and modifications, the differences from the first embodiment will be described in detail, and components similar to those in the first embodiment will be denoted by the same reference numerals, omitting their detailed descriptions.

[0010] <First Embodiment> Figure 1 shows a vehicle display device according to this embodiment. Figure 2A shows the positional relationship between the scanning device and the drawing surface. Figure 2B shows the control method for the scanning device. Figure 3 shows the case when the vehicle display device is damaged.

[0011] As shown in Figure 1, the vehicle display device (hereinafter also simply referred to as "display device") 1 according to this embodiment is mounted on a vehicle. The display device 1 comprises a first laser diode 10, a scanning device 20, and a diffusion member 30.

[0012] The first laser diode 10 emits a first laser beam L1. The scanning device 20 reflects the first laser beam L1 emitted from the first laser diode 10 by controlling the reflection direction. The diffusion member 30 has a drawing surface 31 on a part of its surface. The first laser beam L1 reflected by the scanning device 20 enters the drawing surface 31, scans within the drawing surface 31, and draws an image. The image drawn on the drawing surface 31 of the diffusion member 30 is observed by the observer 200. Preferably, the first laser diode 10, the scanning device 20, and the diffusion member 30 are configured integrally as a single module.

[0013] The display device 1 may further include a light-transmitting member 40. The light-transmitting member 40 is positioned away from the diffusion member 30 and facing the drawing surface 31. For example, the light-transmitting member 40 is positioned parallel to the diffusion member 30. In this case, it is preferable that the first laser diode 10 and the scanning device 20 are positioned outside the region 50 between the diffusion member 30 and the light-transmitting member 40. The image drawn on the drawing surface 31 of the diffusion member 30 is observed by the observer 200 through the light-transmitting member 40.

[0014] As will be described in detail in the fourth embodiment, the light-transmitting member 40 may not be part of the display device 1, but may be a light-transmitting part of the vehicle on which the display device 1 is mounted. The light-transmitting part of the vehicle is a light-transmitting member that constitutes a part of the outer surface of the vehicle.

[0015] The first laser diode 10 emits the first laser beam L1 toward the scanning device 20. The first laser diode 10 is, for example, a CAN package laser diode (NDB7Y75, NDG7D75: Nichia Corporation). The shape and components of the first laser diode 10 are not particularly limited, as long as the light distribution of the emitted first laser beam L1 is other than Lambertian distribution. The scanning device 20 is, for example, a MEMS (Micro Electro Mechanical Systems) mirror or a galvanometer mirror. The scanning device 20 reflects the first laser beam L1 while changing the angle of the mirror and sequentially irradiates the entire area of ​​the drawing surface 31. Preferably, the first laser diode 10 is positioned such that the distance from the light-emitting surface of the first laser diode 10 to the scanning device 20 is within 300 mm in the direction from the light-transmitting member 40 toward the diffusion member 30. It is preferable that the scanning device 20 is positioned such that the distance from the scanning device 20 to the end of the diffusion member 30 is within 500 mm in a direction perpendicular to the direction from the light-transmitting member 40 toward the diffusion member 30.

[0016] At least the portion of the diffusion member 30 that constitutes the drawing surface 31 is formed of a material that diffuses and reflects the first laser beam L1. This portion is, for example, a matte white color. The portion constituting the drawing surface 31 is made of, for example, PET (Polyethylene Terephthalate), PVC (Polyvinyl Chloride), fluororesin, silicon oxide (SiO2). ２ ), titanium oxide (TiO ２ ) or barium sulfate is included. The first laser diode 10 and the scanning device 20 work in conjunction, and each part of the drawing surface 31 diffuses and reflects the first laser light L1, thereby allowing any image to be drawn on the drawing surface 31.

[0017] The light-transmitting member 40 is light-transmitting but not completely transparent; for example, it is a transparent resin plate with a decorative film or diffusion film attached to it. As a result, when the first laser diode 10 is lit and an image is drawn on the drawing surface 31, the observer 200 can see the image through the light-transmitting member 40. On the other hand, when the first laser diode 10 is turned off and no image is drawn on the drawing surface 31, the observer 200 can more easily see the light-transmitting member 40, while the diffusion member 30 becomes more difficult to see.

[0018] Next, the operation of the display device 1 according to this embodiment will be described. The first laser diode 10 emits a first laser beam L1, and the scanning device 20 scans while reflecting the first laser beam L1, so that the first laser beam L1 passes through the region 50 between the diffusion member 30 and the translucent member 40 and sequentially reaches each part of the drawing surface 31 of the diffusion member 30. The first laser beam L1 is diffused and reflected at each part of the drawing surface 31. As a result, the first laser beam L1 becomes light with reduced coherence, and an image is drawn on the drawing surface 31. The light reflected from the drawing surface 31 passes through the region 50 and reaches the translucent member 40, passes through the translucent member 40 and is emitted to the outside of the display device 1. As a result, the observer 200 can observe the image drawn on the drawing surface 31 through the translucent member 40.

[0019] In this way, the display device 1 draws an image on the drawing surface 31 of the diffusion member 30 by linking the first laser diode 10 and the scanning device 20. At this time, the operation of the scanning device 20 is controlled according to the positional relationship between the scanning device 20 and the drawing surface 31, and the shape of the image that the observer 200 is to observe.

[0020] For example, consider the case where, as shown in Figure 1, the scanning device 20 is located far from the normals of all points in the drawing surface 31, and as shown in Figure 2A, the shape of the image to be observed by the observer 200 is rectangular. When the scanning device 20 reflects the first laser beam L1 within a rectangular angular range that matches the shape of the image to be observed by the observer 200, the distance from the scanning device 20 differs for each point in the drawing surface 31. Therefore, the further a point is from the scanning device 20 on the drawing surface 31, the more the area reached by the first laser beam L1 is displaced and stretched along the direction of propagation of the first laser beam L1, causing the image observed by the observer 200 to become distorted.

[0021] Therefore, in order to correct image distortion, it is necessary to control the operation of the scanning device 20 according to the distance from the scanning device 20 and draw the image on the drawing surface 31 of the diffusion member 30. Specifically, as shown in Figure 2B, the scanning device 20 reflects the first laser beam L1 so that it is incident on a region 25 demarcated by two arcs 21 and 22 and two line segments 23 and 24. In region 25, the arc 21 closer to the scanning device 20 is longer than the arc 22 further away from the scanning device 20, one end of arc 21 and one end of arc 22 are connected by line segment 23, and the other end of arc 21 and the other end of arc 22 are connected by line segment 24. Point Pa shown in Figure 2A corresponds to point Pa shown in Figure 2B. The same applies to points Pb to Pi. By controlling the scanning device 20 in this way and controlling the reflection direction of the first laser beam L1 to shorten the distance to points that are farther from the scanning device 20, the image is corrected, and the observer 200 can observe a rectangular image.

[0022] Furthermore, the shape of the image that observer 200 is to observe is not limited to a rectangle; for example, it may be a trapezoid or an ellipse. Even in such cases, by controlling the scanning device 20 to shorten the distance of points that are farther from the scanning device 20 relative to the shape of the image that observer 200 is to observe, the image can be drawn on the drawing surface 31, thereby allowing observer 200 to observe the correct image.

[0023] As shown in Figure 3, even if the diffusion member 30 is damaged due to an impact on the display device 1 or other reasons, the first laser beam L1 emitted from the scanning device 20 will travel through the damaged portion 30x of the diffusion member 30 to the opposite side of the translucent member 40 and will not reach the observer 200. As a result, the observer 200 will not be irradiated with light with high coherence. Furthermore, if the translucent member 40 is damaged, there is a possibility that the light reflected by the diffusion member 30 will reach the observer 200 without passing through the translucent member 40, but the light reflected by the diffusion member 30 is diffused and has reduced coherence.

[0024] Next, the effects of this embodiment will be described. According to this embodiment, by configuring the light source of the display device 1 with a first laser diode 10 and a scanning device 20, CBL can be realized with at least one first laser diode 10. Therefore, it is possible to miniaturize or lighten the vehicle display device that can realize CBL. In addition, since CBL can be realized with at least one first laser diode 10, replacement in the event of failure is easy.

[0025] It is also possible to configure the light source of the display device using multiple LEDs (Light Emitting Diodes). In this case, a large number of LEDs would be required to form the image, and a driver circuit would also be necessary to drive these LEDs. As a result, the size and weight of the display device would increase. Furthermore, replacement in case of failure would likely become more complicated.

[0026] Furthermore, according to this embodiment, as shown in Figure 3, even if the diffusing member 30 or the light-transmitting member 40 is damaged, highly coherent light will not reach the observer 200. For this reason, the display device 1 according to this embodiment is highly safe.

[0027] <First Modification of the First Embodiment> Figure 4 shows a vehicle display device according to this modification. As shown in Figure 4, in the display device 1a according to this modification, the diffusion member 30 is inclined with respect to the light-transmitting member 40. More specifically, the further away from the scanning device 20, the shorter the distance D between the diffusion member 30 and the light-transmitting member 40 becomes.

[0028] The brightness of the image drawn on the drawing surface 31 decreases as the distance from the scanning device 20 on the drawing surface 31 increases, and increases as the distance increases. Similarly, the brightness of the image observed by the observer 200 decreases as the distance from the drawing surface 31 to the observer 200 increases, and increases as the distance increases. By tilting the diffusion member 30 relative to the light-transmitting member 40 to balance the brightness, the observer 200 can observe an image with reduced brightness unevenness. The configuration, operation, and effects of this modified example are the same as those of the first embodiment.

[0029] <Second Modification of the First Embodiment> Figure 5 shows a vehicle display device according to this modification. As shown in Figure 5, the display device 1b according to this modification differs from the display device 1a according to the first modification in that a step is formed on the drawing surface 31 of the diffusion member 30. As a result, two types of regions with different angles to the light-transmitting member 40 are mixed on the drawing surface 31. According to this modification, by forming a step on the drawing surface 31, the brightness can be balanced in the same way as in the first modification.

[0030] <Second Embodiment> Figure 6 shows a part of the vehicle display device according to this embodiment. As shown in Figure 6, the display device 2 according to this embodiment includes a second laser diode 12, a third laser diode 13, and an optical member 15 in addition to the configuration of the display device 1 according to the first embodiment.

[0031] The second laser diode 12 emits a second laser beam L2. The wavelength of the second laser beam L2 is different from the wavelength of the first laser beam L1. The third laser diode 13 emits a third laser beam L3. The wavelength of the third laser beam L3 is different from the wavelengths of the first laser beam L1 and the second laser beam L2. In one example, the first laser beam L1 is blue, the second laser beam L2 is green, and the third laser beam L3 is red. However, it is not limited to this.

[0032] The first laser diode 10 is positioned to emit a first laser beam L1 toward the optical member 15. The second laser diode 12 is positioned to emit a second laser beam L2 toward the optical member 15. The third laser diode 13 is positioned to emit a third laser beam L3 toward the optical member 15.

[0033] The optical member 15 combines the first laser beam L1 emitted from the first laser diode 10, the second laser beam L2 emitted from the second laser diode 12, and the third laser beam L3 emitted from the third laser diode 13, and emits them toward the scanning device 20. The optical member 15 is provided with, for example, a DBR (Distributed Bragg Reflector) 15a that reflects the second laser beam L2 and transmits the first laser beam L1 and the third laser beam L3, and a DBR 15b that reflects the third laser beam L3 and transmits the first laser beam L1 and the second laser beam L2.

[0034] The first laser beam L1 emitted from the first laser diode 10 enters the optical member 15, passes through DBR 15a and DBR 15b, and heads toward the scanning device 20. The second laser beam L2 emitted from the second laser diode 12 enters the optical member 15, is reflected by DBR 15a, passes through DBR 15b, and heads toward the scanning device 20. The third laser beam L3 emitted from the third laser diode 13 enters the optical member 15, is reflected by DBR 15b, passes through DBR 15a, and heads toward the scanning device 20. Note that the configuration of the optical member 15 is not limited to this, and for example, it may be configured by combining prisms.

[0035] According to this embodiment, a color image can be displayed by combining three colors of laser light. Furthermore, compared to the case where the light source of the display device is composed of multiple LEDs, CBL can be realized with a small number of laser diodes, making replacement easier in the event of a failure. The configuration, operation, and effects of this embodiment other than those described above are the same as those of the first embodiment. In this embodiment, an example with three laser diodes is shown, but it is not limited to this, and two or four or more laser diodes may be provided.

[0036] <Third Embodiment> Figure 7 is a plan view showing the diffusion member in this embodiment. Figures 8A and 8B are plan views showing the trajectory of the first laser beam in the diffusion member.

[0037] The display device 3 according to this embodiment comprises a first laser diode 10, a scanning device 20, a diffusion member 60, and a light-transmitting member 40. Note that the light-transmitting member 40 is not part of the display device 3, but may be a light-transmitting part of a vehicle.

[0038] As shown in Figure 7, the drawing surface 61 of the diffusion member 60 is set up with multiple pixel regions 62R, 62G, and 62B, and partition regions 63 arranged between the multiple pixel regions 62R, 62G, and 62B (hereinafter collectively referred to as "pixel regions 62"). The multiple pixel regions 62 are arranged, for example, in a matrix. The shape of each pixel region 62 is, for example, circular. The reflectance of the first laser beam L1 in the partition region 63 is lower than the reflectance of the first laser beam L1 in the pixel region 62.

[0039] Furthermore, the diffusion member 60 has a plurality of wavelength conversion members 64, wavelength conversion members 65, and scattering members 66. The shapes of the wavelength conversion members 64, wavelength conversion members 65, and scattering members 66 are, for example, convex lens-shaped or disc-shaped. The wavelength conversion members 64, wavelength conversion members 65, and scattering members 66 contain a diffusion material that diffuses light, for example, silicon oxide (SiO₂). ２ ), titanium oxide (TiO ２ ) or barium sulfate is contained. Furthermore, wavelength conversion members 64 and 65 contain a wavelength conversion material, for example, a phosphor.

[0040] A wavelength conversion member 64 is located in the pixel region 62R. A wavelength conversion member 65 is located in the pixel region 62G. A scattering member 66 is located in the pixel region 62B. When the first laser beam L1 is irradiated, the wavelength conversion members 64 and 65 convert the first laser beam L1 into light with a different wavelength than the first laser beam L1. When the first laser beam L1 is irradiated, the scattering member 66 scatters the first laser beam L1 without changing its wavelength, thereby reducing its coherence.

[0041] In one example, the first laser beam L1 is blue. The wavelength conversion member 64 converts the blue first laser beam L1 into red light and scatters it. The wavelength conversion member 65 converts the blue first laser beam L1 into green light and scatters it. The scattering member 66 scatters the blue first laser beam L1 as blue light without changing its wavelength.

[0042] In FIG. 7, for the sake of intuitive understanding, the letter "R" is attached to the wavelength conversion member 64, the letter "G" is attached to the wavelength conversion member 65, and the letter "B" is attached to the scattering member 66. However, the color combination is not limited to this. For example, instead of the scattering member 66, a wavelength conversion member that converts the first laser beam L1 into light of another wavelength and diffuses it may be provided.

[0043] As shown in FIG. 8A, the scanning device 20 may make the trajectory T1 of the first laser beam L1 in the diffusion member 60 linear so as to pass through a plurality of pixel regions 62 arranged in a row at the shortest distance. Alternatively, as shown in FIG. 8B, the scanning device 20 may bend or curve the trajectory T1 of the first laser beam L1 within each pixel region 62 to make the trajectory T1 within each pixel region 62 longer than the maximum width of each pixel region 62. When the pixel region 62 is circular, the maximum width of the pixel region 62 is the diameter. Thereby, the time during which the first laser beam L1 irradiates the pixel region 62 becomes longer, and the luminance of the image is improved.

[0044] According to the present embodiment, a color image can be drawn on the drawing screen 61 by at least one first laser diode 10. Further, since the pixel regions 62 are partitioned by the partition regions 63, the contrast of the image is improved. The configurations, operations, and effects other than those described above in the present embodiment are the same as those in the first embodiment. The shape of each pixel region 62 is not limited to a circle, and for example, it may be an ellipse or a polygon, and for example, a square or a regular hexagon. Also, in the present embodiment, an example of displaying an image in three colors is shown, but it is not limited to this, and it may be displayed in two colors or four or more colors.

[0045] <Modification Example of the Third Embodiment>FIG. 9 is a perspective view showing a diffusion member in this modification example. The display device 3a according to this modification example includes a first laser diode 10, a scanning device 20, a diffusion member 70, and a light-transmissive member 40.

[0046] As shown in FIG. 9, the diffusion member 70 has a plurality of cylindrical cases 71 provided on a support member 72. The plurality of cylindrical cases 71 are arranged, for example, in a matrix. In the example shown in FIG. 9, the shape of the case 71 is cylindrical, but it may be square cylindrical or the like. Inside each case 71, a wavelength conversion member 64, a wavelength conversion member 65, and a scattering member 66 are respectively arranged.

[0047] According to this modification example, by partitioning the wavelength conversion member 64, the wavelength conversion member 65, and the scattering member 66 by the case 71, color mixing of light between regions partitioned by adjacent cases 71 can be reduced. The configurations, operations, and effects other than those described above in this modification example are the same as those of the third embodiment.

[0048] <Fourth Embodiment>FIG. 10 is a view showing a vehicle display device according to this embodiment. As shown in FIG. 10, the display device 4 according to this embodiment includes a reflection member 81 and a movable mirror 82 in addition to the configuration of the display device 1 according to the first embodiment.

[0049] In the display device 4, along the optical path of the first laser light L1 emitted from the first laser diode 10, a scanning device 20, a reflection member 81, a movable mirror 82, and a diffusion member 30 are arranged in this order. The screen surface 31 of the diffusion member 30 faces the light-transmissive member 40. The first laser diode 10, the scanning device 20, the reflection member 81, and the movable mirror 82 are arranged outside the region between the diffusion member 30 and the light-transmissive member 40. The reflection member 81 is, for example, a plane mirror. Note that the reflection member 81 may be a concave mirror or a convex mirror. The movable mirror 82 is a structure that can control the reflection direction of incident light, and is, for example, a galvanometer mirror or a MEMS mirror.

[0050] In the display device 4, the first laser beam L1 emitted from the first laser diode 10 is scanned by the scanning device 20, then reflected by the reflecting member 81 toward the movable mirror 82, and reflected by the movable mirror 82 toward the drawing surface 31 of the diffusion member 30. At this time, the movable mirror 82 reflects the first laser beam L1 that reaches a position farther from the movable mirror 82 on the drawing surface 31, such that the angle of incidence and the angle of reflection become larger. For example, the first laser beam L11 that reaches the position closest to the movable mirror 82 on the drawing surface 31 is reflected so that the angle of incidence and the angle of reflection are minimized, and the first laser beam L12 that reaches the position furthest from the movable mirror 82 on the drawing surface 31 is reflected so that the angle of incidence and the angle of reflection are maximized.

[0051] According to this embodiment, the area of ​​the drawing surface 31 can be increased by further controlling the reflection direction of the first laser beam L1 scanned by the scanning device 20 using the movable mirror 82. As a result, an image can be displayed over a wide area of ​​the vehicle's exterior. The configuration, operation, and effects of this embodiment other than those described above are the same as those of the first embodiment.

[0052] Alternatively, the reflective member 81 may be omitted, and the first laser diode 10 and the scanning device 20 may be arranged upside down so that the light emitted from the scanning device 20 directly reaches the movable mirror 82. This allows for miniaturization of the display device 4. In addition, a non-movable convex or concave mirror may be provided instead of the movable mirror 82. This also widens the reflection angle range of the first laser beam L1 and expands the drawing surface 31.

[0053] <Fifth Embodiment> Figure 11 shows a vehicle display device according to this embodiment. As shown in Figure 11, the display device 5 according to this embodiment includes a concave lens 90 in addition to the configuration of the display device 1 according to the first embodiment.

[0054] In the display device 5, the scanning device 20, the concave lens 90, and the diffusion member 30 are arranged in this order along the optical path of the first laser beam L1 emitted from the first laser diode 10. The drawing surface 31 of the diffusion member 30 faces the light-transmitting member 40. The first laser diode 10, the scanning device 20, and the concave lens 90 are located outside the region between the diffusion member 30 and the light-transmitting member 40. The concave lens 90 is positioned so that its optical axis coincides with the optical path of the first laser beam L12 that reaches the point on the drawing surface 31 furthest from the scanning device 20. The concave lens 90 may be a concave lens array.

[0055] In the display device 5, the first laser beam L1 emitted from the first laser diode 10 is scanned by the scanning device 20, then passes through the concave lens 90 and reaches the drawing surface 31 of the diffusion member 30. At this time, the first laser beam L12 that reaches the position furthest from the scanning device 20 on the drawing surface 31 travels along the optical axis of the concave lens 90 and passes through the center of the concave lens 90, so the irradiation area is not greatly expanded by the concave lens 90. The closer the first laser beam L1 that reaches the position furthest from the scanning device 20 on the drawing surface 31, the further it passes through the concave lens 90 from the optical axis of the concave lens 90, and the greater the irradiation area is expanded. The first laser beam L11 that reaches the position closest to the scanning device 20 on the drawing surface 31 has the most greatly expanded irradiation area by the concave lens 90. Because the first laser beam L12 that reaches the position furthest from the scanning device 20 on the drawing surface 31 travels along the optical axis of the concave lens 90, half of the concave lens 90 does not allow the first laser beam L1 to pass through. Therefore, the concave lens 90 may be one that has been divided in half along the optical axis.

[0056] If the concave lens 90 is not provided, the further the first laser beam L1 reaches from the scanning device 20 on the drawing surface 31, the larger the spot diameter Sr on the drawing surface 31 becomes, i.e., the larger the diameter of the area reached by the first laser beam L1. As a result, variations occur in the image quality of the displayed image.

[0057] In contrast, according to this embodiment, the size of the irradiation area can be adjusted according to the optical path of the first laser beam L1 by passing the first laser beam L1 scanned by the scanning device 20 through the concave lens 90. As a result, the closer the first laser beam L1 reaches to the scanning device 20 on the drawing surface 31, the larger the irradiation area becomes and the larger the spot diameter Sr becomes. As a result, the tendency for the spot diameter Sr to increase with increasing distance from the scanning device 20 can be offset by the action of the concave lens 90, which expands the irradiation area for the first laser beam L1 that reaches to a position closer to the scanning device 20, thereby making the spot diameter Sr more uniform. This makes it possible to make the image quality more uniform. The configuration, operation, and effects of this embodiment other than those described above are the same as in the first embodiment.

[0058] <Sixth Embodiment> Figure 12 is a top view showing a vehicle according to this embodiment. In Figure 12, the top of the figure is the front of the vehicle. Figures 13A to 13C show examples of images displayed by the display device.

[0059] As shown in Figure 12, the vehicle 100 in this embodiment is equipped with five vehicle display devices 101 and light-transmitting parts 141, 142, 143, 144, and 145. The display devices 101 are, for example, any of the above-described display devices 1, 1a, 1b, 2, 3, 3a, 4, or 5. The vehicle display devices 101 do not necessarily have light-transmitting members 40. The light-transmitting parts 141, 142, 143, 144, and 145 (hereinafter also simply referred to as "light-transmitting parts") are part of the outer panel of the vehicle 100 and are, for example, light-transmitting resin plates.

[0060] The light-transmitting section 141 is located at the left front corner of the vehicle 100. The light-transmitting section 142 is located at the right front corner of the vehicle 100. The light-transmitting section 143 is located at the rear of the vehicle 100. The light-transmitting section 144 is located at the left door of the vehicle 100. The light-transmitting section 145 is located at the right door of the vehicle 100. In Figure 12, an example is shown in which the light-transmitting sections 144 and 145 are located at the front passenger door, but the light-transmitting sections 144 and 145 may also be located at the rear passenger door, or at both the front and rear passenger doors. A display device 101 is located in close proximity to each light-transmitting section. Each light-transmitting section is located facing the drawing surface of the diffusion member of the display device 101 located in close proximity to it. The image drawn on the drawing surface of the display device 101 is then observed by the observer 200 through the light-transmitting section.

[0061] The image displayed by the display device 101 is, for example, a message to the observer 200. For example, as shown in Figure 13A, when the vehicle 100 turns left, the display device 101 located on the rear of the vehicle 100 displays an image 301 consisting of the symbols and text "← Turn Left"; as shown in Figure 13B, when the vehicle 100 turns right, it displays an image 302 consisting of the symbols and text "Turn Right →"; and as shown in Figure 13C, when the vehicle 100 applies the brakes suddenly, it displays an image 303 consisting of the text "Emergency Stop". In this case, the observer 200 is a pedestrian around the vehicle 100 or the driver of a following vehicle. However, the image displayed by the display device 101 is not limited to these examples and may be a decorative pattern or the like.

[0062] The embodiments and their modifications described above are examples that embody the present invention, and the present invention is not limited to these embodiments and modifications. For example, the present invention also includes the addition, deletion, or modification of some components or processes in the embodiments and modifications described above. Furthermore, the embodiments and modifications described above can be implemented in combination with each other.

[0063] The present invention includes the following embodiments.

[0064] (Note 1) A vehicle display device comprising: a first laser diode; a scanning device that scans by reflecting a first laser beam emitted from the first laser diode; and a diffusion member having a drawing surface to which the first laser beam emitted from the scanning device is incident, wherein the image drawn on the drawing surface of the diffusion member is observed by an observer.

[0065] (Note 2) The vehicle display device according to Note 1, further comprising a translucent member positioned opposite the drawing surface, wherein the image drawn on the drawing surface of the diffusion member is observed by the observer through the translucent member.

[0066] (Note 3) The vehicle display device according to Note 2, wherein the first laser diode and the scanning device are arranged outside the region between the diffusing member and the light-transmitting member.

[0067] (Note 4) The vehicle display device according to Note 2 or 3, wherein the distance between the diffusing member and the light-transmitting member decreases as the distance from the scanning device increases.

[0068] (Note 5) The vehicle display device according to any one of Notes 1 to 4, wherein a step is formed on the drawing surface.

[0069] (Note 6) A vehicle display device according to any one of Notes 1 to 5, further comprising: a second laser diode that emits a second laser beam having a wavelength different from the wavelength of the first laser beam; and an optical member that combines the first laser beam emitted from the first laser diode and the second laser beam emitted from the second laser diode and emits them toward the scanning device.

[0070] (Note 7) The vehicle display device according to Note 6, further comprising a third laser diode that emits a third laser beam having a wavelength different from the wavelength of the first laser beam and the wavelength of the second laser beam, wherein the optical member combines the third laser beam emitted from the third laser diode and emits it toward the scanning device.

[0071] (Note 8) The vehicle display device according to any one of Notes 1 to 5, wherein the diffusion member is arranged on the drawing surface and comprises a wavelength conversion member that converts the first laser light into light of a different wavelength from the wavelength of the first laser light.

[0072] (Note 9) The vehicle display device according to any one of Notes 1 to 8, wherein the drawing surface has a plurality of pixel regions and partition regions arranged between the plurality of pixel regions, and the reflectance of the first laser light in the partition regions is lower than the reflectance of the first laser light in the pixel regions.

[0073] (Note 10) The vehicle display device according to Note 9, wherein the scanning device makes the trajectory of the first laser beam within each pixel area longer than the maximum width of each pixel area.

[0074] (Note 11) A vehicle comprising a vehicle display device described in any one of Notes 1 to 10, and a light-transmitting portion arranged opposite the drawing surface, wherein the image drawn on the drawing surface of the diffusion member is observed by the observer through the light-transmitting portion.

[0075] 1, 1a, 1b, 2, 3, 3a, 4, 5 Vehicle display device 10 First laser diode 12 Second laser diode 13 Third laser diode 15 Optical component 15a, 15b Distributed Bragg reflective film 20 Scanning device 21, 22 Arc 23, 24 Line segment 25 Region 30 Diffusing component 30x Damaged portion 31 Drawing surface 40 Translucent component 50 Region 60 Diffusing component 61 Drawing surface 62, 62B, 62G, 62R Pixel region 63 Partitioned region 64, 65 Wavelength conversion component 66 Scattering component 70 Diffusing component 71 Case 72 Support component 81 Reflecting component 82 Movable mirror 90 Concave lens 100 Vehicle 101 Vehicle display device 141, 142, 143, 144, 145 Translucent section 200 Observers 301, 302, 303 Image D Distance between diffusion member 30 and translucent member 40 L1, L11, L12 First laser beam L2 Second laser beam L3 Third laser beam Pa to Pi Point Sr Spot diameter T1 Trajectory of first laser beam L1

Claims

1. A vehicle display device comprising: a first laser diode; a scanning device that scans by reflecting a first laser beam emitted from the first laser diode; and a diffusion member having a drawing surface to which the first laser beam emitted from the scanning device is incident, wherein the image drawn on the drawing surface of the diffusion member is observed by an observer.

2. The vehicle display device according to claim 1, further comprising a translucent member disposed opposite the drawing surface, wherein the image drawn on the drawing surface of the diffusion member is observed by the observer through the translucent member.

3. The vehicle display device according to claim 2, wherein the first laser diode and the scanning device are arranged outside the region between the diffusing member and the light-transmitting member.

4. The vehicle display device according to claim 2 or 3, wherein the distance between the diffusing member and the light-transmitting member decreases as the distance from the scanning device increases.

5. The vehicle display device according to any one of claims 1 to 4, wherein a step is formed on the drawing surface.

6. A vehicle display device according to any one of claims 1 to 5, further comprising: a second laser diode that emits a second laser beam having a wavelength different from that of the first laser beam; and an optical member that combines the first laser beam emitted from the first laser diode and the second laser beam emitted from the second laser diode and emits them toward the scanning device.

7. The vehicle display device according to claim 6, further comprising a third laser diode that emits a third laser beam having a wavelength different from the wavelength of the first laser beam and the wavelength of the second laser beam, wherein the optical member combines the third laser beam emitted from the third laser diode and emits it toward the scanning device.

8. The vehicle display device according to any one of claims 1 to 5, wherein the diffusion member is disposed on the drawing surface and comprises a wavelength conversion member that converts the first laser light into light of a different wavelength from the wavelength of the first laser light.

9. The vehicle display device according to any one of claims 1 to 8, wherein the drawing surface has a plurality of pixel regions and partition regions arranged between the plurality of pixel regions, and the reflectance of the first laser light in the partition regions is lower than the reflectance of the first laser light in the pixel regions.

10. The vehicle display device according to claim 9, wherein the scanning device makes the trajectory of the first laser beam within each pixel region longer than the maximum width of each pixel region.

11. A vehicle comprising a vehicle display device according to any one of claims 1 to 10, and a light-transmitting portion disposed opposite the drawing surface, wherein the image drawn on the drawing surface of the diffusion member is observed by the observer through the light-transmitting portion.

Images