JP7733633B2 - Virtual Image Display Device - Google Patents

Description

The present invention relates to a virtual image display device. More specifically, it relates to a virtual image display device that displays an image of a nearby traffic participant to be notified on a display unit located in a position visible to the driver.

In recent years, there has been an increase in efforts to provide access to sustainable transportation systems that take into consideration vulnerable transport users. To achieve this, we are focusing on research and development into driver assistance technologies that help drivers recognize their surroundings, thereby further improving road safety and convenience.

The driving assistance technology disclosed in Patent Document 1 assists the driver in recognizing surrounding risk objects by alerting the driver to any obstacles (hereinafter referred to as "risk objects") that may come into contact with the vehicle.

Patent No. 5691237

The driving assistance technology disclosed in Patent Document 1 warns the driver about risk targets by displaying images on a display or by providing audio guidance. As a result, when a driver receives a warning, they can quickly recognize the existence of a risk target and its approximate location, but they cannot quickly recognize how specifically this risk target is approaching their vehicle. As a result, when a driver receives a warning, they cannot quickly recognize the location of the risk target in the near future, and may not be able to quickly determine how specifically they should operate their vehicle to avoid contact with the risk target.

The present invention aims to provide a virtual image display device that allows drivers to quickly recognize the presence of risk objects approaching their vehicle and their movement status, thereby contributing to the development of sustainable transportation systems.

(1) A virtual image display device according to the present invention comprises an external environment recognition device that recognizes nearby traffic participants present around the vehicle; a display unit located in a position visible to the driver of the vehicle; a notification target information acquisition unit that recognizes nearby traffic participants approaching the vehicle as notification targets and acquires notification target information related to the movement state of the notification target; and a display control device that displays an image generated based on the notification target information in a display area of the display unit that includes a notification target image associated with the notification target, wherein the notification target information acquisition unit acquires the notification target information including the relative speed of the notification target relative to the vehicle, and the display control device, when the notification target information acquisition unit recognizes the notification target, displays on the display unit a highlight image that highlights the presence of the notification target on the display unit and a speed graphic image generated based on the notification target information, and changes the form of the speed graphic image according to the relative speed.

(2) In this case, it is preferable that the velocity graphic image has an arrow shape extending from the base end to the tip end, and that the display control device change the inclination of the velocity graphic image in accordance with the relative velocity.

(3) In this case, the velocity graphic image is in the shape of an arrow extending from the base end to the tip, and the display control device preferably changes at least one of the following in accordance with the relative velocity: the inclination of the velocity graphic image, the thickness of the velocity graphic image, the length of the velocity graphic image, the color of the velocity graphic image, the radius of curvature of the velocity graphic image, and the blinking cycle of the velocity graphic image.

(4) In this case, it is preferable that the notification target information acquisition unit acquires the notification target information including a first relative speed of the notification target relative to the host vehicle at the present or in the past, and a second relative speed of the notification target relative to the host vehicle at a predetermined time in the future from the present, and the display control device displays a first speed graphic image generated based on the first relative speed and a second speed graphic image generated based on the second relative speed in the display area.

(5) In this case, it is preferable that the display control device simultaneously displays the first and second velocity graphic images in the display area while aligning the position of the tip end of the first velocity graphic image with the position of the base end of the second velocity graphic image.

(6) In this case, it is preferable that the display control device alternately displays the first speed graphic image and the second speed graphic image in the display area.

(7) In this case, it is preferable that the highlight image is a graphic image having a different shape from the velocity graphic image, and that the display control device displays the highlight image in the display area so that it overlaps with at least a portion of the notification target image.

(8) In this case, it is preferable that the display unit includes an exterior rearview mirror provided outside the cabin of the host vehicle or an interior rearview mirror provided inside the cabin of the host vehicle, and that the display control device sets the portion of the exterior rearview mirror or the interior rearview mirror where the mirror image of the notification target is visible to the driver as the display area, and display the highlight image and the speed graphic image in the display area.

(9) In this case, it is preferable that the display unit includes a windshield, and the display control device sets a portion of the windshield where the real image of the notification target is visible to the driver as the display area, and displays the highlight image and the speed graphic image in the display area.

(10) In this case, the display unit includes a monitor provided in the vehicle interior,
It is preferable that the display control device sets a portion of the monitor where a notification object image associated with the notification object is displayed as the display area, and displays the highlight image and the speed graphic image in the display area.

(1) In the present invention, the notification target information acquisition unit recognizes nearby traffic participants approaching the vehicle as a notification target, acquires notification target information related to the movement state of the notification target, and displays an image generated based on the notification target information in a display area of the display unit that includes the notification target image. In particular, in the present invention, the notification target information acquisition unit acquires notification target information including the relative speed of the notification target relative to the vehicle, and when the display control device recognizes the notification target, displays on the display unit a highlight image that emphasizes the presence of the notification target on the display unit and a speed graphic image whose shape changes depending on the relative speed. In this way, the present invention narrows down the notification targets to only those approaching the vehicle among multiple nearby traffic participants, thereby reducing the annoyance felt by the driver compared to when all nearby traffic participants are notification targets. Furthermore, in the present invention, by displaying a highlight image and a speed graphic image whose shape changes depending on the relative speed in a display area that includes the notification target image on the display unit, the driver can intuitively and quickly recognize not only the presence of the notification target but also its relative speed. Therefore, according to the present invention, driving operations to avoid contact between the vehicle and the notified object can be initiated more quickly than before, thereby contributing to the development of sustainable transportation systems.

(2) In the present invention, the display control device changes the inclination of the arrow-shaped speed graphic image according to the relative speed between the vehicle and the object to be notified. Therefore, the driver can recognize the relative speed simply by checking the inclination of the speed graphic image displayed on the display unit, allowing the driver to more quickly recognize the relative speed of the object to be notified.

(3) In the present invention, the display control device can change at least one of the following aspects of the arrow-shaped speed graphic image: inclination, thickness, length, color, radius of curvature, and blinking cycle, depending on the relative speed, thereby enabling the driver to more quickly recognize the relative speed.

(4) In the present invention, the notification target information acquisition unit acquires notification target information including a first relative speed of the notification target relative to the host vehicle in the present or past and a second relative speed of the notification target relative to the host vehicle in the future, and the display control device displays a first speed graphic image generated based on the first relative speed and a second speed graphic image generated based on the second relative speed in the display area. This allows the driver to quickly recognize the future relative speed as well, and therefore quickly initiate appropriate driving operations to avoid contact between the notification target and the host vehicle.

(5) In the present invention, the display control device simultaneously displays the first and second arrow-shaped velocity graphic images while aligning the tip of the first arrow-shaped velocity graphic image with the base of the second arrow-shaped velocity graphic image. This allows the driver to quickly recognize changes in the current, past, and future movement state of the object to be notified, and therefore allows the driver to quickly initiate appropriate driving operations to avoid contact between the object to be notified and the driver's vehicle.

(6) In the present invention, the display control device alternately displays the first speed graphic image and the second speed graphic image in the display area, allowing the driver to intuitively recognize how the movement state of the object to be notified will change from the present or past to the future, and therefore allowing the driver to quickly initiate appropriate driving operations to avoid contact between the object to be notified and the driver's vehicle.

(7) In the present invention, the display control device displays a highlight image so that it overlaps at least a portion of the image of the notification target displayed on the display unit, thereby enabling the driver to quickly recognize the presence of an approaching notification target from among multiple surrounding traffic participants.

(8) Generally, it may be difficult to recognize the presence and relative speed of a target to be notified simply by looking at the mirror image of the target reflected in the exterior rearview mirror or interior rearview mirror. In response to this, the display control device sets the portion of the exterior rearview mirror or interior rearview mirror where the mirror image of the target to be notified is visible to the driver as a display area, and displays a highlight image or a speed graphic image in this display area. This allows the driver to intuitively and quickly grasp the presence and relative speed of a target to be notified approaching their vehicle simply by looking at the exterior rearview mirror or interior rearview mirror.

(9) The driver can check nearby traffic participants ahead of their vehicle through the windshield. However, when there are multiple such nearby traffic participants, or when the nearby traffic participants are bicycles or motorcycles that are smaller than four-wheeled vehicles, the driver may have difficulty recognizing their presence and relative speed. In response to this, the display control device designates the portion of the windshield where the actual image of the notified object is visible to the driver as the display area, and displays a highlight image or a speed graphic image in this display area. This allows the driver to intuitively and quickly grasp the presence of a notified object approaching their vehicle and its relative speed while looking ahead.

(10) When displaying notification target images associated with multiple surrounding traffic participants on a monitor installed in the vehicle cabin, it is difficult for the driver to recognize which of these multiple surrounding traffic participants is approaching the vehicle. Furthermore, displaying the relative speed of each surrounding traffic participant on the monitor may clutter the monitor's display screen. In response to this, the display control device designates the portion of the monitor where the notification target images associated with the notification targets are displayed as a display area, and displays a highlight image and a speed graphic image in this display area. This allows the driver to intuitively and quickly grasp the presence of a notification target approaching the vehicle and its relative speed simply by looking at the monitor.

1 is a diagram schematically illustrating the configuration of a virtual image display device according to an embodiment of the present invention and a vehicle equipped with the virtual image display device; 1 is a diagram showing an example of a mirror surface of a right exterior rearview mirror used as a display unit as viewed from a driver. FIG. 3 is a diagram showing a first example of a virtual image displayed on the mirror surface of the right exterior rearview mirror under the situation shown in FIG. 2 . FIG. FIG. 10 is a diagram showing the relationship between the current relative speed and the slope of the speed graphic image. 3 is a diagram showing a second example of a virtual image displayed on the mirror surface of the right exterior rearview mirror under the situation shown in FIG. 2 . FIG. 10A and 10B are diagrams showing examples of displaying a current speed graphic image and a future speed graphic image when the future relative speed is higher than the current relative speed; 10A and 10B are diagrams showing examples of displaying a current velocity graphic image and a future velocity graphic image when the future relative velocity is lower than the current relative velocity and is less than 0;

Below, a virtual image display device according to one embodiment of the present invention will be described with reference to the drawings.

Figure 1 is a diagram showing a schematic configuration of a virtual image display device 1 according to this embodiment and a vehicle V (hereinafter simply referred to as "vehicle V") equipped with this virtual image display device 1. In the following, vehicle V will be described as a so-called right-hand drive four-wheel vehicle in which the driver's seat is located on the right side of the vehicle width when viewed along the direction of travel, but the present invention is not limited to this. The vehicle may also be a so-called left-hand drive four-wheel vehicle in which the driver's seat is located on the left side of the vehicle width when viewed along the direction of travel.

The virtual image display device 1 displays images of traffic participants around the vehicle V on a display unit located in a position visible to the driver of the vehicle V, thereby assisting the driver in recognizing the presence of surrounding traffic participants. The following description will be given of the virtual image display device 1 mounted on the vehicle V, a four-wheeled automobile as shown in Figure 1, but the present invention is not limited to this. The present invention may also be mounted on vehicles other than four-wheeled automobiles, such as trucks and saddle-type vehicles. Furthermore, when mounted on a vehicle, particularly a saddle-type vehicle, the virtual image display device may be mounted on a helmet worn by the rider, who is the driver. In this embodiment, traffic participants refer to vehicles, pedestrians, and other people who move based on their own will.

The virtual image display device 1 includes an on-board external environment recognition device 2 that recognizes traffic participants (hereinafter also referred to as "surrounding traffic participants") present around the vehicle V (including in front of, behind, and on both sides of the vehicle V in the direction of travel); a notification target information acquisition unit 3 that acquires notification target information related to the movement state of one or more notification targets selected from one or more surrounding traffic participants recognized by the on-board external environment recognition device 2; a host vehicle information acquisition unit 4 that acquires host vehicle information related to the movement state of the vehicle V; a right exterior rearview mirror 51R and a left exterior rearview mirror 51L that serve as display units located outside the cabin of the vehicle V and in positions visible to the driver; and a display control device 6 that displays virtual images generated based on the notification target information on these exterior rearview mirrors 51R, 51L.

The in-vehicle external environment recognition device 2 includes camera units 21a and 21b, multiple (e.g., five) lidar units 22a, 22b, 22c, 22d, and 22e, multiple (e.g., five) radar units 23a, 23b, 23c, 23d, and 23e, and a surroundings recognition device 24.

The front camera unit 21a and rear camera unit 21b are equipped with digital cameras that use solid-state imaging elements such as CCDs (Charge Coupled Devices) or CMOSs (Complementary Metal Oxide Semiconductors), and capture images of the area ahead and behind the vehicle V. These camera units 21a and 21b are attached to the passenger compartment, for example, on the roof of the vehicle V, facing forward and backward, respectively. The images captured by these camera units 21a and 21b are transmitted to the surroundings recognition device 24.

The LIDAR units 22a to 22e are Light Detection and Ranging (LIDAR) devices that detect objects around the vehicle V by measuring scattered light from the objects in response to pulsed laser illumination. The first LIDAR unit 22a is located in the right corner of the front of the vehicle V when viewed along the direction of travel, and detects objects in front of and slightly to the right of the vehicle V. The second LIDAR unit 22b is located in the left corner of the front of the vehicle V when viewed along the direction of travel, and detects objects in front of and slightly to the left of the vehicle V. The third LIDAR unit 22c is located in the center of the rear of the vehicle V in the vehicle width direction, and detects objects in the rear of the vehicle V. The fourth LIDAR unit 22d is located on the rear side of the right side of the vehicle V, and detects objects in the rear of the vehicle V to the right. The fifth LIDAR unit 22e is located on the rear side of the left side of the vehicle V, and detects objects in the rear of the vehicle V to the left. The detection signals from these lidar units 22a-22e are transmitted to the surroundings recognition device 24.

Radar units 23a to 23e are millimeter-wave radars that detect objects around vehicle V by measuring the waves reflected from the objects in response to millimeter-wave irradiation. The first radar unit 23a is located in the right corner of the front of vehicle V as viewed in the direction of travel, and detects objects slightly forward and to the right of vehicle V. The second radar unit 23b is located in the left corner of the front of vehicle V as viewed in the direction of travel, and detects objects slightly forward and to the left of vehicle V. The third radar unit 23c is located in the center of the front of vehicle V in the vehicle width direction, and detects objects slightly forward and to the right of vehicle V. The fourth radar unit 23d is located in the right corner of the rear of vehicle V as viewed in the direction of travel, and detects objects slightly rearward and to the right of vehicle V. The fifth radar unit 23e is located in the left corner of the rear of vehicle V as viewed in the direction of travel, and detects objects slightly rearward and to the left of vehicle V. The detection signals of these radar units 23a to 23e are transmitted to the surroundings recognition device 24.

The surroundings recognition device 24 performs sensor fusion processing on the detection results from the camera units 21a and 21b, lidar units 22a-22e, and radar units 23a-23e to recognize one or more surrounding traffic participants and acquire surrounding traffic participant information related to the type and movement status (i.e., location, movement direction, movement speed, movement acceleration, etc.) of each surrounding traffic participant. The surroundings recognition device 24 transmits information related to the recognition results of the surrounding traffic participants, i.e., the acquired surrounding traffic participant information, to the notification target information acquisition unit 3.

The vehicle information acquisition unit 4 acquires vehicle information related to the movement state of the vehicle V (i.e., position, movement direction, movement speed, movement acceleration, etc.). The vehicle information acquisition unit 4 transmits the acquired vehicle information to the notification target information acquisition unit 3.

The notification target information acquisition unit 3 recognizes one or more of the surrounding traffic participants recognized by the surrounding recognition device 24 as notification targets based on the surrounding traffic participant information transmitted from the surrounding recognition device 24 of the in-vehicle external environment recognition device 2 and the host vehicle information transmitted from the host vehicle information acquisition unit 4, and acquires notification target information regarding the movement state of these notification targets.

More specifically, the notification target information acquisition unit 3 identifies the position, movement speed, and movement direction of each surrounding traffic participant based on the surrounding traffic participant information, determines whether each surrounding traffic participant is approaching vehicle V based on this position, movement speed, and movement direction, and recognizes only those of all surrounding traffic participants determined to be approaching vehicle V as notification targets. Here, the notification target information acquisition unit 3 determines that, of all surrounding traffic participants, for example, a surrounding traffic participant moving from ahead of vehicle V in the direction of travel toward vehicle V, a surrounding traffic participant moving from behind vehicle V in the direction of travel toward vehicle V at a faster speed than vehicle V, and a surrounding traffic participant ahead of vehicle V in the direction of travel and about to cross in front of vehicle V are approaching vehicle V and recognizes them as notification targets.

Next, the notification target information acquisition unit 3 acquires notification target information regarding the movement state of each notification target recognized through the above procedure, based on the surrounding traffic participant information and the host vehicle information. More specifically, the notification target information acquisition unit 3 calculates the current or past relative speed of each notification target relative to vehicle V (hereinafter also referred to as the "current relative speed") and the future relative speed of each notification target relative to vehicle V a predetermined time from the present (e.g., several seconds from now) (hereinafter also referred to as the "future relative speed"), based on the surrounding traffic participant information and the host vehicle information.

More specifically, the notification target information acquisition unit 3 extracts, for example, the current or past moving speed and moving direction of each notification target and vehicle V from the surrounding traffic participant information and the host vehicle information, and calculates the current relative speed based on these current or past moving speeds and moving directions. The notification target information acquisition unit 3 also extracts, for example, the current or past moving acceleration of each notification target and vehicle V from the surrounding traffic participant information and the host vehicle information, calculates the future moving speed of each notification target and vehicle V based on these moving accelerations, and further calculates the future relative speed based on these future moving speeds.

Hereinafter, the current relative speed and future relative speed calculated for each notification target by the notification target information acquisition unit 3 using the above procedure will be collectively referred to as notification target information. When the notification target information acquisition unit 3 recognizes at least one notification target from one or more surrounding traffic participants, it transmits notification target information including the current relative speed and future relative speed for each notification target to the display control device 6.

When a notification target is recognized by the notification target information acquisition unit 3, the display control device 6 generates a virtual image based on the notification target information to encourage the driver to quickly and appropriately recognize the notification target, and displays the generated virtual image on a display unit located in a position visible to the driver in the vehicle V.

In this embodiment, the display control device 6 uses the exterior rearview mirrors 51R, 51L as display units and displays virtual images on these exterior rearview mirrors 51R, 51L, but the present invention is not limited to this.

Figure 2 is a diagram showing an example of the mirror surface of the right exterior rearview mirror 51R as viewed from the driver. Below, the procedure for displaying a virtual image on the right exterior rearview mirror 51R by the display control device 6 will be described for a case in which another vehicle traveling to the right rear of vehicle V among multiple surrounding traffic participants is recognized as a notification target, and the mirror image 9M of this notification target is reflected on the mirror surface of the right exterior rearview mirror 51R as shown in Figure 2. This other vehicle is traveling to the right rear of vehicle V in the direction of travel and is approaching vehicle V at a faster speed than vehicle V, so it is recognized as a notification target by the notification target information acquisition unit 3.

When at least one notification target is recognized by the notification target information acquisition unit 3, the display control device 6 generates a virtual image for each notification target based on the notification target information and displays the generated virtual image in a display area of the display unit that is defined to include the notification target image associated with each notification target. In this embodiment, in which the exterior rearview mirrors 51R, 51L are used as the display unit as described above, the display control device 6 defines a display area 80 to include the portion of the mirror surface of the exterior rearview mirrors 51R, 51L that is visible to the driver as the mirror image 9M of the notification target, as shown in FIG. 2, and displays the generated virtual image in this display area 80.

Figure 3 shows a first example of a virtual image 8 displayed on the mirror surface of the right exterior rearview mirror 51R under the circumstances shown in Figure 2. When a notification target is recognized, the display control device 6 displays the virtual image 8, including a highlight image 81 and a current speed graphic image 82 as shown in Figure 3, within a display area 80 defined to include the mirror image 9M of the notification target.

The highlight image 81 is a graphic image that emphasizes the presence of the mirror image 9M of the notification target reflected in the exterior rearview mirrors 51R, 51L, and has a different shape from the speed graphic image 82. As shown in FIG. 3, the display control device 6 displays the highlight image 81 in the display area 80 so that it overlaps at least a portion of the mirror image 9M. More specifically, the shape of the highlight image 81 is, for example, an oval as shown in FIG. 3, and the color of the highlight image 81 is, for example, a translucent red. This allows the driver to quickly recognize the presence and position of the mirror image 9M of the notification target reflected in the exterior rearview mirrors 51R, 51L.

As described above, in this embodiment, the display control device 6 displays an elliptical, transparent, red highlight image 81 in the display area 80, but the present invention is not limited to this. The highlight image 81 may have any shape as long as it is a graphic image that emphasizes the presence of the mirror image 9M of the notification target reflected in the exterior rearview mirrors 51R, 51L and has a shape different from the speed graphic image 82. The shape of the highlight image 81 can be freely set by the driver via a specified setting operation.

The speed graphic image 82 is an arrow-shaped graphic image extending from the base end to the tip end, as shown in FIG. 3. The display control device 6 displays the speed graphic image 82 generated based on the notification target information within the display area 80 and slightly above the mirror image 9M of the notification target, as shown in FIG. 3. The display control device 6 also obtains the current relative speed of the notification target from the notification target information, and changes the shape of the arrow-shaped speed graphic image 82, or more specifically, the inclination of the speed graphic image 82, in accordance with this current relative speed. In other words, the speed graphic image 82 is a graphic image that indicates the relative speed of the notification target with respect to vehicle V by its inclination.

Figure 4 is a diagram showing the relationship between the current relative speed and the slope of the speed graphic image 82. As shown in Figure 4, the display control device 6, for example, causes the slope of the speed graphic image 82 to approach 0 as the current relative speed of the object to be notified approaches 0, and increases the slope of the speed graphic image 82 to the positive side as the current relative speed of the object to be notified increases. This allows the driver to intuitively and quickly recognize the relative speed of the object to be notified simply by looking at the speed graphic image 82.

In this embodiment, the display control device 6 changes only the slope of the velocity graphic image 82, which is made up of the slope, thickness, color, radius of curvature, and blinking period, in accordance with the relative speed, but the present invention is not limited to this. The display control device 6 may also change at least one of the slope, thickness, length, color, radius of curvature, and blinking period of the velocity graphic image 82 in accordance with the relative speed.

When the display control device 6 changes the thickness of the speed graphic image 82 according to the relative speed, it may, for example, make the speed graphic image 82 thinner as the relative speed of the target to be notified approaches zero, and make the speed graphic image 82 thicker as the relative speed of the target to be notified increases. When the display control device 6 changes the length of the speed graphic image 82 according to the relative speed, it may, for example, make the speed graphic image 82 shorter as the relative speed of the target to be notified approaches zero, and make the speed graphic image 82 longer as the relative speed of the target to be notified increases. When the display control device 6 changes the color of the speed graphic image 82 according to the relative speed, it may, for example, make the speed graphic image 82 closer to a less noticeable color (e.g., green) as the relative speed of the target to be notified approaches zero, and make the speed graphic image 82 closer to a more noticeable color (e.g., red) as the relative speed of the target to be notified increases. When the display control device 6 changes the radius of curvature of the speed graphic image 82 in accordance with the relative speed, it may, for example, increase the radius of curvature of the speed graphic image 82 as the relative speed of the target to be notified approaches zero, and decrease the radius of curvature of the speed graphic image 82 as the relative speed of the target to be notified increases. When the display control device 6 changes the blinking period of the speed graphic image 82 in accordance with the relative speed, it may, for example, increase the blinking period of the speed graphic image 82 as the relative speed of the target to be notified approaches zero, and decrease the blinking period of the speed graphic image 82 as the relative speed of the target to be notified increases. Note that the form of the speed graphic image 82 that changes in accordance with the relative speed in the display control device 6 can be freely set by the driver via a predetermined setting operation.

When a target to be notified is recognized, the display control device 6 displays a virtual image 8 including a highlight image 81 and a speed graphic image 82 generated by the above procedure on the exterior rearview mirrors 51R, 51L, thereby encouraging the driver to recognize the presence of the target to be notified and its relative speed.

Figure 5 shows a second example of the virtual image 8A displayed on the mirror surface of the right exterior rearview mirror 51R under the circumstances shown in Figure 2.

When both the current relative speed and future relative speed of the target to be notified have been acquired by the notification target information acquisition unit 3 as described above, the display control device 6 may display in the display area 80 a virtual image 8A that includes both a current speed graphic image 83 generated based on the current relative speed and a future speed graphic image 84 generated based on the future relative speed, as illustrated in Figure 5. Note that Figure 5 shows a case where the future relative speed is higher than the current relative speed.

The current speed graphic image 83 and the future speed graphic image 84 are each arrow-shaped graphic images extending from the base end to the tip end, as illustrated in FIG. 5. The display control device 6 displays the speed graphic images 83, 84 generated based on the notification target information within the display area 80 and slightly above the mirror image 9M of the notification target, as illustrated in FIG. 5. The display control device 6 obtains the current relative speed of the notification target from the notification target information, and changes the shape of the arrow-shaped current speed graphic image 83, more specifically the slope of the current speed graphic image 83, in accordance with this current relative speed. The display control device 6 obtains the future relative speed of the notification target from the notification target information, and changes the shape of the arrow-shaped future speed graphic image 84, more specifically the slope of the future speed graphic image 84, in accordance with this future relative speed.

As explained with reference to FIG. 4, the display control device 6, for example, causes the slope of the current speed graphic image 83 to approach 0 as the current relative speed of the object to be notified approaches 0, increases the slope of the current speed graphic image 83 to the positive side as the current relative speed of the object to be notified increases, causes the slope of the future speed graphic image 84 to approach 0 as the future relative speed of the object to be notified approaches 0, and increases the slope of the future speed graphic image 84 to the positive side as the future relative speed of the object to be notified increases.

In this embodiment, the display control device 6 simultaneously displays the current speed graphic image 83 and the future speed graphic image 84 in the display area 80 while aligning the position of the tip of the current speed graphic image 83 with the position of the base of the future speed graphic image 84, as illustrated in Figure 5, but the present invention is not limited to this.

The display control device 6 may alternately display the current speed graphic image 83 and future speed graphic image 84 generated as described above at the same position within the display area 80 at predetermined intervals. At this time, the display control device 6 may use so-called morphing to continuously switch from the current speed graphic image 83 to the future speed graphic image 84. That is, when switching from the current speed graphic image 83 to the future speed graphic image 84, the display control device 6 may continuously switch from the current speed graphic image 83 to the future speed graphic image 84 by sequentially displaying multiple intermediate state graphic images generated by combining these two speed graphic images 83, 84.

In this embodiment, the display control device 6 changes only the slope of each of the speed graphic images 83, 84, which are composed of slope, thickness, color, radius of curvature, and blinking period, in accordance with the relative speed, but the present invention is not limited to this. The display control device 6 may also change at least one of the slope, thickness, length, color, radius of curvature, and blinking period of each speed graphic image 83, 84 in accordance with the relative speed. In this case, the display control device 6 may also change different forms for the current speed graphic image 83 and the future speed graphic image 84.

Figure 6 shows an example of the display of a current speed graphic image 83 and a future speed graphic image 84 when the future relative speed is higher than the current relative speed.

As shown in the upper part of Figure 6, the display control device 6 may change only the slope of the current speed graphic image 83 in accordance with the current relative speed, and change both the slope and blinking cycle of the future speed graphic image 84 in accordance with the future relative speed. This makes it possible to emphasize an increase in future relative speed.

Furthermore, as shown in the middle section of Figure 6, the display control device 6 may change both the inclination and color of the current speed graphic image 83 according to the current relative speed, and change both the inclination and color of the future speed graphic image 84 according to the future relative speed. This makes it possible to emphasize an increase in future relative speed.

Also, as shown in the lower part of Figure 6, the display control device 6 may change only the slope of the current speed graphic image 83 in accordance with the current relative speed, and change only the radius of curvature of the future speed graphic image 84 in accordance with the future relative speed. This makes it possible to emphasize an increase in future relative speed.

Figure 7 shows an example of the display of the current speed graphic image 83 and future speed graphic image 84 when the future relative speed is lower than the current relative speed and is less than 0.

As shown in the upper part of Figure 7, the display control device 6 may change only the slope of the current speed graphic image 83 in accordance with the current relative speed, and change both the slope and thickness of the future speed graphic image 84 in accordance with the future relative speed. This makes it possible to emphasize a decrease in future relative speed.

Furthermore, as shown in the middle section of Figure 7, the display control device 6 may change both the inclination and color of the current speed graphic image 83 according to the current relative speed, and change both the inclination and color of the future speed graphic image 84 according to the future relative speed. This makes it possible to emphasize a decrease in future relative speed.

Also, as shown in the lower part of Figure 7, the display control device 6 may change only the slope of the current speed graphic image 83 in accordance with the current relative speed, and change only the radius of curvature of the future speed graphic image 84 in accordance with the future relative speed. This makes it possible to emphasize the decrease in future relative speed.

The virtual image display device 1 according to this embodiment has the following advantages.
(1) The notification target information acquisition unit 3 recognizes a nearby traffic participant approaching the vehicle V as a notification target and acquires notification target information regarding the movement state of the notification target. The display control device 6 then displays a virtual image 8 generated based on the notification target information in a display area 80 in the exterior rearview mirrors 51R, 51L, the display area 80 being determined to encompass a mirror image 9M of the notification target. In particular, in this embodiment, the notification target information acquisition unit 3 acquires notification target information including the relative speed of the notification target relative to the vehicle V. When the notification target is recognized, the display control device 6 displays a highlight image 81 in the exterior rearview mirrors 51R, 51L that emphasizes the presence of the notification target and speed graphic images 82-84, the shape of which changes depending on the relative speed. In this embodiment, by narrowing down the notification targets to only those approaching the vehicle V among multiple nearby traffic participants, the driver's annoyance can be reduced compared to when all nearby traffic participants are designated as notification targets. In addition, in this embodiment, a highlight image 81 and speed graphic images 82-84 whose appearance changes depending on the relative speed are displayed in a display area 80 including a mirror image 9M of the object to be notified reflected in the exterior rearview mirrors 51R, 51L, thereby enabling the driver to intuitively and quickly recognize not only the presence of the object to be notified but also the relative speed. Therefore, according to this embodiment, the driver can start driving operations to avoid contact between the vehicle V and the object to be notified more quickly than before, which can also contribute to the development of sustainable transportation systems.

(2) In this embodiment, the display control device 6 changes the inclination of the arrow-shaped speed graphic images 82-84 depending on the relative speed between the vehicle V and the object to be notified. Therefore, the driver can recognize the relative speed simply by checking the inclination of the speed graphic images 82-84 displayed in the exterior rearview mirrors 51R, 51L, thereby enabling the driver to more quickly recognize the relative speed of the object to be notified.

(3) In this embodiment, the display control device 6 changes at least one of the following aspects of the arrow-shaped speed graphic images 82-84: the inclination, thickness, length, color, radius of curvature, and blinking cycle, depending on the relative speed, thereby enabling the driver to more quickly recognize the relative speed.

(4) In this embodiment, the notification target information acquisition unit 3 acquires notification target information including the current or past relative speed of the notification target relative to the host vehicle and the future relative speed of the notification target relative to the host vehicle, and the display control device 6 displays in the display area 80 a current speed graphic image 83 generated based on the current relative speed and a future speed graphic image 84 generated based on the future relative speed. This allows the driver to quickly recognize the future relative speed as well, and therefore quickly initiate appropriate driving operations to avoid contact between the notification target and vehicle V.

(5) In this embodiment, the display control device 6 simultaneously displays the arrow-shaped current speed graphic image 83 and future speed graphic image 84 while aligning the tip end of the arrow-shaped current speed graphic image 83 with the base end of the arrow-shaped future speed graphic image 84. This allows the driver to quickly recognize changes in the current, past, and future movement state of the object to be notified, and therefore allows the driver to quickly initiate appropriate driving operations to avoid contact between the object to be notified and vehicle V.

(6) In this embodiment, the display control device 6 alternately displays the current speed graphic image 83 and the future speed graphic image 84 in the display area, allowing the driver to intuitively recognize how the movement state of the object to be notified will change from the present or past to the future, and therefore allowing the driver to quickly initiate appropriate driving operations to avoid contact between the object to be notified and the vehicle V.

(7) In this embodiment, the display control device 6 displays the highlight image 81 so that it overlaps at least a portion of the mirror image 9M of the notification target reflected in the exterior rearview mirrors 51R, 51L, allowing the driver to quickly recognize the presence of an approaching notification target from among multiple surrounding traffic participants.

(8) Generally, it may be difficult to recognize the presence and relative speed of a target to be notified simply by looking at the mirror image 9M of the target to be notified reflected in the exterior rearview mirrors 51R, 51L. In response to this, the display control device 6 defines a display area 80 that encompasses the portion of the exterior rearview mirrors 51R, 51L from which the driver can see the mirror image 9M of the target to be notified, and displays a highlight image 81 and speed graphic images 82-84 in this display area 80. This allows the driver to intuitively and quickly grasp the presence of a target to be notified approaching vehicle V and its relative speed simply by looking at the exterior rearview mirrors 51R, 51L.

The above describes one embodiment of the present invention, but the present invention is not limited to this. Detailed configurations may be modified as appropriate within the spirit and scope of the present invention.

For example, in the above embodiment, the display control device 6 uses the exterior rearview mirrors 51R, 5L as display units, defines a display area 80 so as to encompass the portion of the mirror surface of these exterior rearview mirrors 51R, 51L where the mirror image 9M of the notification target is visible to the driver, and displays a virtual image within this display area 80, but the present invention is not limited to this.

The display control device may use an interior rearview mirror, which is located inside the vehicle cabin and visible to the driver, as the display unit, and may define a display area that encompasses the portion of the interior rearview mirror where the mirror image of the object to be notified is visible to the driver, and may display a virtual image within this display area. This allows the driver to intuitively and quickly grasp the presence of an object to be notified approaching their vehicle and its relative speed simply by looking at the interior rearview mirror.

The display control device may use the windshield located in front of the driver as a display unit, define a display area to include the portion of the windshield where the real image of the notification target is visible to the driver, and display a virtual image within this display area. This allows the driver to intuitively and quickly grasp the presence of a notification target approaching their vehicle and its relative speed while looking ahead.

The display control device may also use a monitor installed inside the vehicle cabin as the display unit, define a display area to encompass the portion of the monitor where the notification target image associated with the notification target is displayed, and display a virtual image within this display area. This allows the driver to intuitively and quickly grasp the presence of a notification target approaching the vehicle and its relative speed simply by looking at the monitor.

In the above embodiment, the in-vehicle external environment recognition device 2 recognized the traffic participants around vehicle V based on information acquired using in-vehicle sensors that move with vehicle V, such as camera units 21a-21b and lidar units 22a-22e. However, the present invention is not limited to this. The in-vehicle external environment recognition device 2 may also recognize the traffic participants around vehicle V based on information acquired via vehicle-to-vehicle communication between vehicle V and the traffic participants, wireless communication between vehicle V and a traffic management server, or the like.

V... Vehicle 1... Virtual image display device 2... In-vehicle external environment recognition device (external environment recognition device)
3: Notification target information acquisition unit 4: Vehicle information acquisition unit 51R: Right exterior rearview mirror 51L: Left exterior rearview mirror 6: Display control device 8, 8A: Virtual image 80: Display area 81: Highlight image 82, 83: Current speed graphic image 84: Future speed graphic image

Claims (6)

an external environment recognition device that recognizes surrounding traffic participants present around the vehicle;
a display unit including an exterior rearview mirror provided outside the vehicle cabin or an interior rearview mirror provided inside the vehicle cabin;
a notification target information acquisition unit that recognizes a person approaching the vehicle among the surrounding traffic participants as a notification target and acquires notification target information relating to a moving state of the notification target;
a display control device that displays an image generated based on the notification target information in a display area including a portion of the vehicle exterior rearview mirror or the vehicle interior rearview mirror where a mirror image of a notification target image associated with the notification target is visible to a driver of the vehicle,
the notification target information acquisition unit acquires the notification target information including a relative speed of the notification target with respect to the host vehicle;
The display control device is a virtual image display device characterized in that, when the notification target is recognized by the notification target information acquisition unit, it displays on the display unit a highlight image that emphasizes the presence of the notification target and an arrow-shaped velocity graphic image extending from the base end to the tip , which is generated based on the notification target information, and changes the inclination of the velocity graphic image according to the relative velocity. the notification target information acquisition unit acquires the notification target information including a first relative speed of the notification target with respect to the host vehicle at the present or in the past, and a second relative speed of the notification target with respect to the host vehicle at a future time after a predetermined time from the present,
2. The virtual image display device according to claim 1, wherein the display control device displays, in the display area, a first velocity graphic image , which is the velocity graphic image generated based on the first relative velocity, and a second velocity graphic image, which is the velocity graphic image generated based on the second relative velocity. 3. The virtual image display device according to claim 2, wherein the display control device simultaneously displays the first and second velocity graphic images in the display area while aligning the position of the tip of the first velocity graphic image with the position of the base of the second velocity graphic image. 3. The virtual image display device according to claim 2 , wherein the display control device alternately displays the first speed graphic image and the second speed graphic image in the display area. the highlight image is a graphic image having a different shape from the velocity graphic image,
The virtual image display device according to claim 2 , wherein the display control device displays the highlight image in the display area so as to overlap at least a part of the image of the notification object. an external environment recognition device that recognizes surrounding traffic participants present around the vehicle;
a display unit including a windshield provided at a position visible to a driver of the vehicle;
a notification target information acquisition unit that recognizes a person approaching the vehicle among the surrounding traffic participants as a notification target and acquires notification target information relating to a moving state of the notification target;
a display control device that displays an image generated based on the notification target information in a display area including a portion of the windshield where a real image of a notification target image associated with the notification target is visible to the driver,
the notification target information acquisition unit acquires the notification target information including a relative speed of the notification target with respect to the host vehicle;
The display control device is a virtual image display device characterized in that, when the notification target is recognized by the notification target information acquisition unit, it displays on the display unit a highlight image that emphasizes the presence of the notification target and an arrow-shaped velocity graphic image extending from the base end to the tip, which is generated based on the notification target information, and changes the inclination of the velocity graphic image according to the relative velocity.