Image display system

Abstract

The image display system (10) of the present application is provided with: a projector (12) mounted on an object vehicle (30) and projecting an image onto a road surface around the object vehicle (30); and an image controller (20) that causes the projector (12) to project a support image (62) onto the road surface around the object vehicle (30) in a case where another vehicle (40) traveling behind the object vehicle (30) has started a passing operation of the object vehicle (30), wherein the support image (62) includes at least one of an image indicating a non-entry range in which entry of the another vehicle (40) is prohibited and an image indicating a passing range in which the another vehicle (40) should pass at the time of the passing operation.

Description

[0001] This application claims priority to Japanese Patent Application No. 2021-199592, filed December 8, 2021, which includes the entire contents of the specification, claims, drawings, and abstract of the specification by reference herein. TECHNICAL FIELD

[0002] The present specification discloses an image display system that projects an image onto a road surface of a periphery of a vehicle to display. BACKGROUND

[0003] In recent years, a technology is known that projects an image onto a road surface of a periphery of a vehicle using a projector mounted on the vehicle. For example, a vehicle depicting device that makes a mark on a road surface in a traveling direction of a vehicle at the time when a turn signal lamp is turned on is disclosed in Patent Literature 1. According to this technology, it is possible to explicitly transmit the traveling direction of the vehicle to a driver of another vehicle or a pedestrian at the time of a lane change or a turn, and thus the safety is improved.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2016-193689

[0007] However, according to the technology of Patent Literature 1, the road surface projection of the image is performed only when a specific action (in this case, the turning on of the turn signal lamp) is performed by the vehicle (hereinafter referred to as “target vehicle”) itself on which the projector is mounted. Therefore, in the technology of Patent Literature 1, the road surface projection is not performed in a case where another vehicle traveling behind the target vehicle overtakes the target vehicle. In other words, in the conventional technology, the road surface projection technology is not used for improving the safety at the time when another vehicle overtakes the target vehicle. SUMMARY

[0008] Therefore, in the present specification, an image display system that can further improve the safety at the time when another vehicle traveling behind a target vehicle overtakes the target vehicle is disclosed.

[0009] The image display system disclosed in the present specification is characterized by comprising: a projector mounted on a target vehicle that projects an image onto a road surface of a periphery of the target vehicle; and an image controller that causes the projector to project a support image onto the road surface of the periphery of the target vehicle in a case where another vehicle traveling behind the target vehicle has started a passing action of the target vehicle, wherein the support image includes at least one of an image indicating a non-entry range in which entry of the other vehicle is prohibited and an image indicating a passing range in which the other vehicle should pass at the time of the passing action.

[0010] With this configuration, the driver of the other vehicle can easily recognize the range in which the other vehicle cannot enter or the range in which the other vehicle should pass when the overtaking operation is performed, and thus the safety of the overtaking operation can be improved.

[0011] In this case, the image controller can also determine at least one of a turning condition of the other vehicle traveling behind and a light-up condition of a turn signal of the other vehicle based on a result of sensing by the rear sensor, and determine the start of the overtaking operation based on at least one of the turning condition and the light-up condition and the relative speed.

[0012] With this configuration, the start of the overtaking operation can be accurately determined. Furthermore, generally, many vehicles are equipped with a sensor that senses a state of the rear of the vehicle. By using this sensor as the rear sensor, the start of the overtaking operation can be determined without adding a new sensor.

[0013] In this case, the image controller can determine at least one of a turning condition of the other vehicle traveling behind and a light-up condition of a turn signal of the other vehicle based on a result of sensing by the rear sensor, and determine the start of the overtaking operation based on at least one of the turning condition and the light-up condition and the relative speed.

[0014] With this configuration, the start of the overtaking operation can be more accurately determined.

[0015] Furthermore, the image controller can end the projection of the support image based on at least a result of sensing by the rear sensor.

[0016] With this configuration, the support image can be prevented from being projected for an unnecessarily long time. Also, as a result, power consumption can be suppressed. Furthermore, by ending the projection of the support image at an appropriate timing, other vehicles and pedestrians that are not involved in the overtaking operation can be prevented from being confused by the support image.

[0017] Furthermore, the image controller can end the projection of the support image based on at least an elapsed time from the start of the overtaking operation.

[0018] With this configuration, the timing at which the projection of the support image ends can be determined by a simple configuration. Furthermore, with this configuration, the support image can be prevented from being projected for an unnecessarily long time. Also, as a result, power consumption can be suppressed. Furthermore, by ending the projection of the support image at an appropriate timing, other vehicles and pedestrians that are not involved in the overtaking operation can be prevented from being confused by the support image.

[0019] Alternatively, it may also include a front sensor that senses the state in front of the target vehicle, and the image controller terminates the projection of the supporting image based at least on the sensing results of the front sensor.

[0020] By employing this configuration, the projection of the support image can be terminated at the precise time when other vehicles approach the target vehicle—in other words, at the precise time when the overtaking maneuver is reliably completed. Furthermore, this configuration prevents the support image from being projected unnecessarily for extended periods. Moreover, this reduces power consumption. Additionally, by terminating the projection of the support image at an appropriate time, confusion can be prevented from being caused by other vehicles or pedestrians unrelated to the overtaking maneuver seeing the support image.

[0021] Alternatively, the image controller may change at least one of the size and projection position of the supporting image based on the steering of the object vehicle.

[0022] By adopting this configuration, the activities of the target vehicle can be communicated to the drivers of other vehicles, thus enabling other vehicles to overtake more safely.

[0023] Alternatively, it may also include an acceleration sensor that senses the acceleration of the target vehicle in the width direction, and the image controller changes at least one of the size and projection position of the supporting image based on the sensing result of the acceleration sensor.

[0024] By adopting this configuration, the activities of the target vehicle, especially the activities that the target vehicle's driver does not want (such as the activities of the target vehicle caused by strong winds, uneven road surfaces, etc.), can be communicated to the drivers of other vehicles, so that other vehicles can overtake more safely.

[0025] The image display system disclosed in this specification can further improve the safety of other vehicles traveling behind the target vehicle when overtaking it. Attached Figure Description

[0026] Figure 1 It is a block diagram representing the structure of an image display system.

[0027] Figure 2 This is a schematic diagram representing a vehicle in motion.

[0028] Figure 3 This is a schematic diagram illustrating a scenario where a supporting image is depicted.

[0029] Figure 4 This is a schematic diagram illustrating another example of image support.

[0030] Figure 5This is a schematic diagram illustrating another example of image support.

[0031] Explanation of reference numerals in the attached figures

[0032] 10: Image display system; 12: Projector; 14: Rear sensor; 16: Front sensor; 17: Steering angle sensor; 18: Accelerometer sensor; 20: Image controller; 22: Processor; 24: Memory; 30: Object vehicle; 32: Rear sensing area; 34: Front sensing area; 40: Other vehicles; 50: Driving lane; 52: Shoulder; 54: Sidewalk; 56: Oncoming lane; 58: Center line; 60: Outer lane line; 62: Supporting image. Detailed Implementation

[0033] The configuration of the image display system 10 will now be described with reference to the accompanying drawings. Figure 1 This is a block diagram illustrating the configuration of the image display system 10. The image display system 10 is mounted on a vehicle and projects images of the road surface surrounding the vehicle.

[0034] like Figure 1 As shown, the image display system 10 includes a projector 12, a rear sensor 14, a front sensor 16, a steering angle sensor 17, an acceleration sensor 18, and an image controller 20. The projector 12 projects an image onto the road surface surrounding the target vehicle. The projector 12 is not limited in its configuration; it can be any device that has one or more light sources and can illuminate the road surface with light constituting the image. Therefore, the projector 12 can be a liquid crystal projector that uses light from LEDs (Light Emitting Diodes) or similar sources to project images, such as an LCD (Liquid Crystal Display), DLP (Digital Light Processing), or LCOS (Liquid Crystal on Silicon) projector. Alternatively, the projector 12 can also be a device that uses a lens to project light from a light source such as a typical headlight. Furthermore, in this example, the projector 12 has the function of changing the content, position, and size of the image depicted on the road surface.

[0035] The rear sensor 14 is a sensor that senses the state behind a target vehicle. More specifically, the rear sensor 14 senses the state of a predetermined rear sensing area set behind the target vehicle. The rear sensor 14 can sense whether there are other vehicles in the rear sensing area and the distance to other vehicles located in the rear sensing area. In addition, the rear sensor 14 may also sense at least one of the positions of other vehicles and the illumination status of other vehicles' turn signals. The rear sensor 14 may, for example, have multiple sensors separately disposed at multiple locations on the target vehicle. For example, the rear sensor 14 may have at least one of a camera, millimeter-wave radar, submillimeter-wave radar, ultrasonic sensor, and LiDAR (light detection and ranging).

[0036] The front sensor 16 senses the state of a predetermined front sensing area positioned in front of the target vehicle. The front sensor 16 senses the presence of other vehicles within the front sensing area, their distance to other vehicles, their positions, and the illumination status of their turn signals. This front sensor 16 may, for example, comprise multiple sensors separately disposed at multiple locations on the target vehicle. For example, the front sensor 16 may include at least one of a camera, millimeter-wave radar, submillimeter-wave radar, ultrasonic sensor, or LiDAR.

[0037] The steering angle sensor 17 senses the steering of the target vehicle. The steering angle sensor 17 is, for example, mounted on the steering shaft of the target vehicle and senses the direction and angle of rotation of the steering shaft. The steering angle sensor 17 is, for example, an optical or magnetic rotary encoder.

[0038] Accelerometer 18 senses the acceleration of the target vehicle along three orthogonal axes: the vehicle's longitudinal axis, vertical axis, and width axis. The sensing results are sent to image controller 20. Image controller 20 calculates the vehicle's speed by integrating the sensed acceleration and calculates the vehicle's displacement by performing a second-order integral of the acceleration. It should be noted that, typically, for driver assistance (e.g., automatic braking, lane keeping assist, etc.) and driving control, vehicles are equipped with sensors such as cameras and millimeter-wave radar. Such existing sensors can be used as sensors 14, 16, 17, and 18. Alternatively, in addition to existing sensors, dedicated sensors can be added to the vehicle for the image display system 10.

[0039] The image controller 20 controls the operation of the projector 12 to project an image onto the road surface. More specifically, the image controller 20 determines, based on the sensing results of the rear sensor 14, whether other vehicles traveling behind the target vehicle have begun overtaking maneuvers. If it is determined that other vehicles have begun overtaking maneuvers, the image controller 20 instructs the projector 12 to project the supporting image 62, described later, onto the road surface.

[0040] The graphics controller 20 is a computer that physically has a processor 22 and a memory 24. This "computer" also includes a microcontroller that embeds the computer system within an integrated circuit. Furthermore, processor 22 refers to a processor in a broad sense, including general-purpose processors (e.g., CPU: Central Processing Unit), and special-purpose processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic devices, etc.).

[0041] Memory 24 refers to a device for storing digital data to be processed by a computer. Memory 24 includes at least one of a main memory connected to processor 22 via a memory bus and an auxiliary storage device accessed by processor 22 via an input / output channel. Memory 24 may include at least one of semiconductor memory (e.g., RAM, ROM, solid-state drive, etc.) and disk (e.g., hard disk drive, etc.). In this example, memory 24 is pre-installed with a program used to sense whether other vehicles are overtaking based on the sensing results of rear sensor 14, and to cause projector 12 to project a predetermined image onto the road surface based on the sensing results.

[0042] Such an image controller 20 can be a single computer or composed of multiple mechanically separate computers. Furthermore, the image controller 20 can be specifically designed for the image display system 10. Alternatively, an existing computer pre-installed in the target vehicle for purposes such as drive control can be used as the image controller 20. Additionally, a portion of the processing by the image controller 20 can be performed by another computer located outside the target vehicle.

[0043] Next, the image display processing performed by such an image display system 10 will be described. Figure 2 This is a schematic diagram representing the vehicle 30 in motion. Furthermore, Figure 3 This is a schematic diagram depicting a scenario supporting image 62.

[0044] exist Figure 2 , Figure 3 In this scenario, vehicle 30 travels in a single-lane road according to the left-hand traffic rule. Therefore, there is a center line 58 at the right end of the vehicle 30's lane 50 and an outer lane line 60 at the left end. Furthermore, there is an oncoming lane 56 to the right of the center line 58, and a shoulder 52 exists between the outer lane line 60 and the sidewalk 54.

[0045] As described above, the target vehicle 30 is equipped with a rear sensor 14 and a front sensor 16. In the illustrated example, the rear sensor 14 has three sensors located near the rear end of the target vehicle 30, and the sensing range of these three sensors is the rear sensing area 32. Similarly, the front sensor 16 has three sensors located near the front end of the target vehicle 30, and the sensing range of these three sensors is the front sensing area 34.

[0046] The image controller 20 monitors whether other vehicles 40 traveling behind the target vehicle 30 have initiated an overtaking maneuver. Here, "overtaking" refers to the act of changing lanes to get ahead of the vehicle in front. "Overtaking" also includes "squeezing past" where a two-wheeled vehicle passes the side of a four-wheeled vehicle without changing lanes. On the other hand, "overtaking" does not include "overtaking" on a single-lane road where other vehicles in adjacent lanes (such as overtaking lanes) maintain their lane-changing state and overtake a vehicle traveling in one lane.

[0047] The image controller 20 can, for example, determine the start of an overtaking maneuver based on the relative speed of other vehicles 40 relative to the target vehicle 30. For instance, the image controller 20 can determine that an overtaking maneuver has begun if the relative speed is greater than a predetermined reference speed. In this case, the reference speed can always be a fixed value. Alternatively, the reference speed can be a variable value that varies depending on the distance between the target vehicle 30 and other vehicles 40, the speed of the target vehicle 30, the type of other vehicles 40 (i.e., whether they are four-wheeled or two-wheeled), traffic congestion, the speed limit of the driving lane 50, and the actions of other vehicles 40 (described later). For example, if other vehicles 40 are sufficiently close to the target vehicle 30, the distance is small, but the relative speed is still large, the probability of other vehicles 40 overtaking is high. Therefore, the smaller the distance, the smaller the reference speed can be. Furthermore, if the goal is to complete the overtaking in N seconds, when the speed of the target vehicle 30 is set to Vt and the coefficient is set to A, the theoretical relative speed Vr required for overtaking is Vr = √(Vt × A / N). In other words, the higher the speed Vt of the target vehicle 30, the higher the relative speed Vr required to overtake in N seconds. Therefore, the higher the speed Vt of the target vehicle 30, the higher the baseline speed for determining the start of overtaking. Furthermore, in the overtaking vehicle ( Figure 4 When other vehicles (40) in the lane are four-wheeled vehicles, it is easier for them to cross into the adjacent lane compared to when the overtaking vehicle is a two-wheeled vehicle. Therefore, generally speaking, four-wheeled vehicles have a higher necessity to complete the overtaking maneuver quickly compared to two-wheeled vehicles, and it can be said that the relative speed required for overtaking is greater. Therefore, when other vehicles (40) are four-wheeled vehicles, the base speed can be greater compared to when other vehicles (40) are two-wheeled vehicles.

[0048] It should be noted that the relative speed can be determined based on the sensing results of the rear sensor 14. For example, if the rear sensor 14 is a millimeter-wave radar or submillimeter-wave radar that senses the vehicle-to-vehicle distance, the image controller 20 can determine the relative speed based on the change in vehicle-to-vehicle distance sensed by the millimeter-wave radar or the like. Furthermore, if the rear sensor 14 is a camera that captures images of the rear of the target vehicle 30, the image controller 20 can determine the vehicle-to-vehicle distance and thus the relative speed by analyzing the obtained images.

[0049] Furthermore, the image controller 20 can also determine the start of an overtaking maneuver based on the actions of other vehicles 40, in addition to relative speed. For example, the image controller 20 can determine that an overtaking maneuver has begun when the relative speed is sufficient for overtaking and other vehicles 40 have moved laterally. Such lateral movement of other vehicles 40 can be sensed, for example, by analyzing changes in the position of other vehicles 40 sensed by millimeter-wave radar or the like, or by analyzing images captured by a camera. Furthermore, the image controller 20 can determine that an overtaking maneuver has begun when the relative speed is sufficient for overtaking and other vehicles 40 have activated their turn signals. Such activation of turn signals can be sensed by analyzing images captured by a camera. Thus, by considering the actions of other vehicles 40 in addition to relative speed, the start of an overtaking maneuver can be determined more accurately.

[0050] exist Figure 3 In this scenario, when the image controller 20 determines that another vehicle 40 has initiated an overtaking maneuver, it instructs the projector 12 to project a support image 62 onto the road surface. The support image 62 is an image that supports the overtaking maneuver of the target vehicle 30 by the other vehicle 40. In this example, the support image 62 represents an inaccessible area where other vehicles 40 are prohibited from entering during the overtaking maneuver. That is, for safe overtaking, other vehicles 40 need to maintain a certain distance from the target vehicle 30 to avoid interference. In other words, for safe overtaking, a certain area around the target vehicle 30 should be designated as an inaccessible area where other vehicles 40 are prohibited from entering. The support image 62 represents such an inaccessible area.

[0051] exist Figure 3 In the example, supporting image 62 is a shape formed by combining lines representing the boundaries of inaccessible areas with crosses representing inaccessibility. Furthermore, in Figure 3 In this example, the supporting image 62 is displayed only to the side of the target vehicle 30. The supporting image 62 can be projected only to the left or right of the target vehicle 30, or it can be projected to both sides. For example, if it is predicted that another vehicle 40 will pass on the right side of the target vehicle 30 to overtake, the supporting image 62 can be projected only onto the road surface to the right of the target vehicle 30. In short, by avoiding the inaccessible area shown by the supporting image 62, the other vehicle 40 can safely perform overtaking maneuvers without interfering with the target vehicle 30.

[0052] After the projection of supporting image 62 begins, the image controller 20 may terminate the projection of supporting image 62 at a time when the rear sensor 14 can no longer detect other vehicles 40, that is, at a time when other vehicles 40 have moved outside the rear sensing area 32. Alternatively, after the projection of supporting image 62 begins, the image controller 20 may terminate the projection of supporting image 62 at a time when the front sensor 16 can detect other vehicles 40, that is, at a time when other vehicles 40 have moved into the front sensing area 34. Furthermore, as another option, after the projection of supporting image 62 begins, the image controller 20 may terminate the projection of supporting image 62 at a time after a predetermined overtaking time has elapsed. In this case, the overtaking time is the time at which other vehicles 40 have finished overtaking the target vehicle 30. This overtaking time can be a fixed value or a variable value that varies according to relative speed, etc. Furthermore, the image controller 20 can also combine the above-mentioned techniques, for example, by ending the projection of the supported image 62 at either the earlier of the timing when the overtaking time has elapsed or the timing when the forward sensor 16 can detect other vehicles 40. Alternatively, the timing for ending the projection of the supported image 62 can be determined based on conditions other than those described above.

[0053] Next, the supporting image 62 will be described in detail. As described above, the supporting image 62 in this example is an image representing an inaccessible area where other vehicles 40 are prohibited from overtaking. The form of the supporting image 62 (i.e., size, projection position, shape, brightness, color, etc.) can be either always fixed or can be changed according to the actions of the target vehicle 30.

[0054] For example, the vehicle 30 may sometimes move in the width direction unrelated to steering wheel operation due to road surface irregularities or wind. Furthermore, the driver of the vehicle 30 may sometimes operate the steering wheel for various reasons, causing the vehicle 30 to move in the width direction. If such movement of the vehicle 30 in the width direction can be communicated to other vehicles 40, those vehicles 40 can perform overtaking maneuvers more safely.

[0055] Therefore, the image controller 20 can change at least one of the size and projection position of the supporting image 62 according to the activity of the object vehicle 30. Specifically, the image controller 20 can change the width W of the supporting image 62 based on the sensing results of the rudder angle sensor 17 and the acceleration sensor 18.

[0056] For example, when the driver of vehicle 30 turns the steering wheel to either the left or right, vehicle 30 moves in the direction of the turn. In this case, to safely perform an overtaking maneuver, it is necessary to ensure a wide no-entry zone in the direction of the turn. Therefore, when steering to either the left or right is detected by steering angle sensor 17, image controller 20 can increase the width W of the support image 62 in the direction of the turn based on the steering angle amount, or shift the projection position of the support image 62 in the direction of the turn based on the steering angle amount. Thus, when the steering wheel is turned to the right, for example, the width W of the support image 62 on the right side of vehicle 30 can be made larger than the width of the support image 62 on the left side.

[0057] Furthermore, even when the driver is not operating the steering wheel, the target vehicle 30 may sometimes move in the width direction due to road surface irregularities, wind, etc. Such movement can be sensed by the acceleration sensor 18 and reflected in the supporting image 62. Therefore, for example, if acceleration in the width direction is sensed by the acceleration sensor 18, the image controller 20 can change at least one of the width W and projection position of the supporting image 62 based on the direction and magnitude of the acceleration. For example, if the acceleration sensed by the acceleration sensor 18 indicates that the target vehicle 30 is swaying in the width direction, the image controller 20 can either increase the width W of the supporting image 62 based on the amplitude of the swaying, or shift the projection position of the supporting image 62 away from the target vehicle 30 based on the amplitude of the swaying. Furthermore, if the acceleration indicates that the target vehicle 30 is moving in either the left or right direction, the image controller 20 can either increase the width W of the support image 62 in the direction of movement based on the sensed acceleration, or shift the projection position of the support image 62 in the direction of movement towards the direction of movement based on the sensed acceleration.

[0058] Furthermore, the image controller 20 can change at least one of the size and projection position of the supporting image 62 based on other conditions. For example, when overtaking, the distance that should be maintained between the target vehicle 30 and other vehicles 40 varies depending on weather, vehicle speed, road width, etc. Therefore, the width W and projection position of the supporting image 62 can also be changed taking into account weather, vehicle speed, and road width. For example, in the event of rain, snow, strong winds, or icy roads, the width W of the supporting image 62 can be increased. Rain and snow can be sensed by a rain sensor mounted on the vehicle for the automatic wiper function. In addition, icy roads can be estimated based on the sensing results of a temperature sensor. Furthermore, the image controller 20 can also estimate conditions such as rain, snow, strong winds, and icy roads based on meteorological information obtained through internet communication, etc., in addition to the sensing results of such sensors, or it can estimate conditions such as rain, snow, strong winds, and icy roads based on meteorological information obtained through internet communication, etc., instead of the sensing results of such sensors.

[0059] Furthermore, at least one of the width W and projection position of the supporting image 62 can be changed based on the speed of the target vehicle 30 or the relative speed of other vehicles 40 relative to the target vehicle 30. For example, a greater relative speed can result in a larger width W of the supporting image 62. Moreover, at least one of the width W and projection position of the supporting image 62 can also be changed based on the road width. For example, if the driving lane 50 itself is wide or if there is an overtaking lane adjacent to the driving lane 50, the width W of the supporting image 62 can be increased. The road width can be determined, for example, based on map information recorded in the navigation device or by analyzing images captured by a camera.

[0060] Furthermore, the size and projection position of such supporting image 62 can also be set so that it does not extend beyond the oncoming lane 56 and sidewalk 54 (including the "roadside strip"). To achieve this configuration, image controller 20 can analyze images captured by a camera mounted on the target vehicle 30 to determine the relative positions of the oncoming lane 56 and sidewalk 54 relative to the target vehicle 30.

[0061] Furthermore, the configuration of the supporting image 62 itself can be appropriately modified. For example, during overtaking, other vehicles 40 often interfere with the rear and front corners of the target vehicle 30. Therefore, to prevent such interference, the supporting image 62 can be made longer than the total length of the target vehicle 30, and the front-rear end of the supporting image 62 can be located further outward in the front-rear direction than the front-rear end of the target vehicle 30. That is, the supporting image 62 can be set to be in... Figure 4 The shape is indicated by reference numeral 62a in the attached figure.

[0062] Furthermore, such as Figure 5As shown, the supporting image 62 is not limited to being projected to the side of the target vehicle 30, but can also be projected to the front and rear of the target vehicle 30. When the supporting image 62 is also projected to the front of the target vehicle 30, the driver of the target vehicle 30 can easily visually recognize the supporting image 62. Furthermore, by visually recognizing the supporting image 62, the driver of the target vehicle 30 can easily perceive the presence of other vehicles 40 that intend to overtake the target vehicle 30, thus improving the safety of overtaking maneuvers.

[0063] In addition, Figure 3 In the example, the supporting image 62 is set as a shape composed of a rectangle and a cross, but the supporting image 62 only needs to be a shape that the drivers of other vehicles 40 can understand the meaning represented by the supporting image 62, and can be changed to other shapes. Therefore, as in Figure 4 As indicated by reference numeral 62a in the accompanying drawings, the supporting image 62 can also be configured as a shape combining a line representing the boundary of an inaccessible area with a road sign indicating no entry.

[0064] Furthermore, in the previous description, the supporting image 62 was set as an image representing the inaccessible range of other vehicles 40, but the supporting image 62 can also be set as an image representing the passage range that other vehicles 40 should pass when overtaking. Figure 4 Reference numeral 62b is an example of a supporting image indicating the passage range. Figure 4 It is understood that the support image 62b, indicating the passable range, is projected onto the road surface outside the inaccessible range. Furthermore, in this case, the support image 62b can be shaped to encourage the passage of other vehicles 40, for example, by including an arrow indicating the direction of travel. Additionally, the support image 62b can also be shaped to include stripes or a grid. With this shape, the driver of the other vehicle 40 can easily perceive the unevenness of the road surface based on the deformation of the lines forming the stripes or grid. As a result, the driver of the other vehicle 40 makes driving operations that take this unevenness into account, thus enabling safer overtaking maneuvers. Furthermore, the image controller 20 can project the road surface onto either the support image 62a indicating the inaccessible range or the support image 62b indicating the passable range, or it can project the road surface onto both simultaneously.

[0065] Furthermore, the image controller 20 can also adjust the brightness of the supporting image 62 based on the ambient light around the target vehicle 30. For example, in bright environments like outdoor daytime, the brightness of the supporting image 62 can be increased compared to dark environments such as nighttime or tunnels. The brightness can be determined based on the sensing results of a brightness sensor installed for the automatic lighting function, or based on the illumination status of lights such as headlights that are required to be on at night. Additionally, the color of the supporting image 62 can be changed based on the road surface color. For example, in the case of a road surface painted red for anti-skid purposes, the color of the supporting image 62 can be changed to a color with less red content compared to a normal asphalt road without red paint. It should be noted that the road surface color can be determined by analyzing images captured by a camera. Furthermore, the supporting image 62 can also be a moving image that changes over time. For example, Figure 4 The supporting image 62b can be set as a motion image in which at least one of the position, color and size of the arrow contained in the supporting image 62b changes over time.

[0066] As explained above, when another vehicle 40 begins overtaking, the image display system 10 disclosed in this specification projects a support image 62 indicating the prohibited area and / or passable area onto the road surface. As a result, interference between the target vehicle 30 and other vehicles 40 can be effectively prevented, further improving the safety of the overtaking maneuver of the other vehicle 40. It should be noted that the above configuration is merely an example; simply projecting the support image 62 onto the road surface when another vehicle 40 begins overtaking is sufficient, and other configurations can be appropriately modified. For example, the types of vehicles of the target vehicle 30 and other vehicles 40 are not specific. Therefore, the target vehicle 30 and other vehicles 40 can be two-wheeled vehicles, four-wheeled vehicles, or other types of vehicles. Furthermore, the image display system 10 can also project other types of images onto the road surface besides the aforementioned support image 62. For example, the image display system 10 can also project an image indicating the direction of travel of the target vehicle 30 onto the road surface when the target vehicle 30 turns left or right.

Claims

1. An image display system, characterized in that, have: A projector, mounted on the target vehicle, projects images onto the road surface surrounding the target vehicle; A rear sensor that senses the state behind the target vehicle; A front sensor that senses the state of the area in front of the target vehicle; as well as When the rear sensor detects that another vehicle traveling behind the target vehicle has begun overtaking, the image controller causes the projector to project a support image onto the road surface surrounding the target vehicle. The support image includes an image representing an inaccessible area where other vehicles are prohibited from entering, and an image representing a passable area where other vehicles should proceed during the overtaking maneuver. The image controller is configured to, at a time when the front sensor detects the other vehicle, cause the projector to stop projecting the supporting image.

2. The image display system according to claim 1, characterized in that, The image controller calculates the relative speed between the other vehicle traveling behind and the target vehicle based on the sensing results of the rear sensor, and determines the start of the overtaking action based at least on the relative speed.

3. The image display system according to claim 2, characterized in that, The image controller determines at least one of the steering status and the illumination status of the steering signal of the other vehicle traveling behind based on the sensing results of the rear sensor, and determines the start of the overtaking action based on at least one of the steering status and the illumination status, as well as the relative speed.

4. The image display system according to claim 2, characterized in that, The image controller also determines the end of the projection of the supporting image based on the sensing results of the rear sensor.

5. The image display system according to any one of claims 1 to 4, characterized in that, The image controller also determines the end of the projection of the supporting image based on the elapsed time since the start of the overtaking maneuver.

6. The image display system according to any one of claims 1 to 4, characterized in that, The image controller changes at least one of the size and projection position of the supporting image based on the steering of the object vehicle.

7. The image display system according to any one of claims 1 to 4, characterized in that, It also includes an acceleration sensor that senses the acceleration of the target vehicle in the width direction. The image controller is configured to determine the amplitude of the sway in the width direction of the target vehicle based on the sensing results of the acceleration sensor. The larger the amplitude of the sway, the wider the support image becomes, or the more the projection position of the support image is shifted away from the target vehicle.

8. The image display system according to claim 1, characterized in that, The image controller is configured to: when it is predicted that another vehicle will pass on either side of the target vehicle in order to overtake, project the support image onto the road surface on either side of the target vehicle, and on the other hand, not project the support image onto the road surface on the other side.

9. The image display system according to claim 1, characterized in that, The image controller is configured to increase the width of the supporting image under specific conditions, such as rain, snow, strong winds, or icy roads, compared to conditions not under those specific conditions.

10. The image display system according to claim 1, characterized in that, The image controller is configured to project the supporting image onto the road surface in front of the target vehicle in response to the rear sensor sensing that another vehicle traveling behind the target vehicle has begun overtaking.

Images