Vehicle display device, control method for vehicle display device, and program

Abstract

The aim is to minimize the inconvenience of having an image displayed on the windshield (20) while increasing the likelihood that the driver (P) of the vehicle (1) will be able to understand the risk indicators (2). [Solution] The vehicle display device (23) includes a detection unit (101) that detects risk indicators (2) that are located in front of the vehicle (1) and that may come into contact with the vehicle (1), and a display control unit (108) that displays an image on the windshield (20) of the vehicle (1). The display control unit (108) temporarily displays a visibility reduction image (VG) on the windshield (20) in an area other than the risk indicator range (R1) corresponding to the risk indicator (2) detected by the detection unit (101), which reduces the visibility of the driver (P) of the vehicle (1).

Description

Technical Field

[0001] The present invention relates to a vehicle display device, a control method for the vehicle display device, and a program.

Background Art

[0002] Conventionally, there is known a technique for enabling a driver of a vehicle to grasp a risk index, which is an index that may come into contact with the vehicle. For example, Patent Document 1 discloses a technique for suppressing unnecessary line-of-sight induction to objects other than the visual recognition object to be gazed at by performing a visual field restriction on a salient portion that does not require the driver's visual recognition by displaying an image on the front windshield. Also, for example, Patent Document 2 discloses a technique for displaying an image on a windshield. The technique disclosed in Patent Document 2 improves the visibility of an obstacle by restricting the display of lane line information when the lane line information displayed on the windshield overlaps with the obstacle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Patent documents 1 and 2 describe technologies that increase the likelihood of vehicle drivers being able to grasp risk indicators. However, in Patent Document 1, while saliency that does not need to be visually perceived by the driver is being extracted from the camera's captured images, an image that restricts the driver's view is displayed on the windshield, which the driver may find bothersome. Similarly, in Patent Document 2, while information on the road markings in front of the vehicle is being acquired, lane marking information is displayed on the windshield, which the driver may find bothersome. Therefore, the present invention aims to increase the likelihood that vehicle drivers can grasp risk indicators while suppressing the inconvenience of having images displayed on the windshield. Ultimately, this will contribute to further improving traffic safety and the development of a sustainable transportation system. [Means for solving the problem]

[0005] One aspect of the present invention is a vehicle display device comprising: a detection unit for detecting risk indicators located in front of a vehicle and potentially in contact with the vehicle; and a display control unit for displaying an image on the windshield of the vehicle, wherein the display control unit temporarily displays a visibility reduction image on the windshield in an area other than the risk indicator range corresponding to the risk indicator detected by the detection unit, the visibility of the vehicle to the driver of the vehicle being reduced. [Effects of the Invention]

[0006] According to one aspect of the present invention, it is possible to increase the likelihood that the driver of a vehicle can grasp risk indicators while suppressing the inconvenience of having an image displayed on the windshield. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 shows the configuration of the vehicle. [Figure 2] Figure 2 shows the layout of the vehicle's interior. [Figure 3] Figure 3 shows the configuration of the vehicle display device. [Figure 4] Figure 4 is a diagram illustrating the calculation of the distance between viewpoint indicators. [Figure 5] Figure 5 is a diagram illustrating the processing of the display control unit. [Figure 6] Figure 6 shows an example of an image with reduced visibility. [Figure 7] Figure 7 is a flowchart showing the operation of the vehicle display device. [Modes for carrying out the invention]

[0008] The first embodiment will be described below with reference to the drawings. Figures 1, 2, 4, 5, and 6 illustrate the X, Y, and Z axes. The X, Y, and Z axes are orthogonal to each other. The Z axis indicates the vertical direction. The X and Y axes are parallel to the horizontal direction when vehicle 1 is in motion. The X axis indicates the left-right direction as the vehicle width direction. The Y axis indicates the front-rear direction. The positive direction of the X axis is to the right. The positive direction of the Y axis is forward. The positive direction of the Z axis is upward.

[0009] [1. Vehicle Configuration] Figure 1 shows the configuration of vehicle 1. The vehicle 1 illustrated in Figure 1 is a four-wheeled vehicle. Vehicle 1 is equipped with a driver's seat 10A, a passenger seat 10B, a rear right seat 10C, and a rear left seat 10D. In vehicle 1 in Figure 1, the driver P is seated in the driver's seat 10A.

[0010] Vehicle 1 is equipped with a touch panel 12. The touch panel 12 consists of a display panel that displays characters and images and a touch sensor that detects contact with the display panel, which are superimposed or integrated together.

[0011] Vehicle 1 is equipped with speakers 13, 14, 15, and 16. Speaker 13 outputs sound to the driver P seated in the driver's seat 10A. Speaker 14 outputs sound to the passenger seated in the front passenger seat 10B. Speaker 15 outputs sound to the passenger seated in the rear right seat 10C. Speaker 16 outputs sound to the passenger seated in the rear left seat 10D. Note that the installation positions of speakers 13, 14, 15, and 16 are not limited to those shown in Figure 1, but are acceptable as long as they can output sound to the passenger seated in the corresponding seat. Hereafter, if speakers 13, 14, 15, and 16 are not distinguished, they will be referred to as "speaker 17" by adding the designation "17". Speaker 17 is an example of a "stimulus output device." The sound output by speaker 17 is an example of a "stimulus."

[0012] Vehicle 1 is equipped with a front camera 18 that photographs the area in front of Vehicle 1. The front camera 18 is located at the front of Vehicle 1 and photographs the area in front of Vehicle 1. The front camera 18 takes pictures at predetermined intervals when the ignition of Vehicle 1 is on or when the accessory power of Vehicle 1 is on. Each time the front camera 18 takes a picture, it outputs the image data of the captured image SG (see, for example, Figure 4) obtained from the picture to the vehicle display device 23.

[0013] Vehicle 1 is equipped with a Head-Up Display (HUD) 19. The HUD 19 projects light onto the windshield 20, thereby displaying an image on the windshield 20. As a result, the driver P seated in the driver's seat can view the displayed image along with the scenery in front of Vehicle 1 by the HUD 19 displaying the image on the windshield 20.

[0014] Figure 2 shows the interior layout of vehicle 1. The interior of the vehicle 1 shown in Figure 2 is equipped with an instrument panel 21 on which a HUD 19 is located. The instrument panel 21 also includes a steering wheel for operating the vehicle 1, a touch panel 12, and a speaker 13.

[0015] In FIG. 2, the HUD 19 illustrates a displayable area A1 where an image can be displayed as an area closed by a dotted line L1. The size of the displayable area A1 corresponds to the size of the magnifying mirror (concave mirror) provided in the HUD 19. Note that the size of the displayable area A1 with respect to the windshield 20 is not limited to the size shown in FIG. 2. Also, in FIG. 2, a shape in which the longitudinal direction of the displayable area A1 is the vehicle width direction is illustrated, but the shape of the displayable area A1 is not limited to the shape shown in FIG. 2.

[0016] Returning to the description of FIG. 1, the vehicle 1 includes a driver monitoring camera 22. The driver monitoring camera 22 is a camera provided at a predetermined position in the vehicle interior of the vehicle 1 and photographs the driver P sitting in the driver's seat 10A. The imaging range of the driver monitoring camera 22 is a range including at least the head HD of the driver P sitting in the driver's seat १०A. The driver monitoring camera 22 performs imaging at a predetermined cycle when the ignition of the vehicle 1 is on or when the accessory power supply of the vehicle 1 is on. Each time the driver monitoring camera 22 performs imaging, it outputs the image data of the captured image obtained by the imaging to the vehicle display device 23.

[0017] The vehicle 1 includes a vehicle display device 23. The vehicle display device 23 is a device that displays an image on the windshield 20 by the HUD 19.

[0018] [2. Configuration of Vehicle Display Device] FIG. 3 is a diagram showing the configuration of the vehicle display device 23. The vehicle display device 23 includes a processor 100 such as a CPU (Central Processing Unit) or an MPU (Micro-processing unit), a memory 110, and an interface circuit to which other devices and sensors are connected.

[0019] The processor 100 controls each part of the vehicle display device 23 by reading and executing the control program 111 stored in the memory 110. By executing the control program 111 stored in the memory 110, the processor 100 functions as the risk indicator detection unit 101, gaze detection unit 102, eye detection unit 103, driver state detection unit 104, determination unit 105, TTC calculation unit 106, speaker control unit 107, and display control unit 108. The risk indicator detection unit 101 is an example of a "detection unit". The speaker control unit 107 is an example of a "stimulus control unit".

[0020] Memory 110 is a storage device that stores programs executed by the processor 100 and data processed by the processor 100. Memory 110 stores control programs 111 executed by the processor 100 and various other data. Memory 110 has a non-volatile storage area. Memory 110 also has a volatile storage area and constitutes the work area of ​​the processor 100. Memory 110 is composed of, for example, ROM (Read Only Memory) and RAM (Random Access Memory). Control program 111 corresponds to "program".

[0021] The vehicle display device 23 is connected to a speaker 17, a front camera 18, a HUD 19, a driver monitoring camera 22, a position detection device 24, and a vehicle speed sensor 25. Furthermore, if vehicle 1 has a driver assistance function, a driver assistance device 26 is connected to the vehicle display device 23. Also, if vehicle 1 has an autonomous driving function, an autonomous driving device 27 is connected to the vehicle display device 23. Note that the devices connected to the vehicle display device 23 are not limited to these; other devices such as a vehicle-to-vehicle communication device, a GNSS (Global Navigation Satellite System) unit, and a rear camera may also be connected.

[0022] The position detection device 24 is a device capable of detecting the position of objects present around the vehicle 1. The position detection device 24 consists of at least one of the following: a sonar, radar, lidar, etc., capable of measuring the distance between the vehicle 1 and an object, and a stereo camera capable of measuring the distance between the vehicle 1 and an object using parallax.

[0023] The vehicle speed sensor 25 is a sensor that detects the speed of vehicle 1. The vehicle speed sensor 25 detects the speed of vehicle 1 at predetermined intervals and outputs a signal corresponding to the detected speed of vehicle 1 to the vehicle display device 23 each time it detects a speed.

[0024] The driver assistance device 26 is a device for performing driver assistance functions to assist the driver P in driving the vehicle 1. The driver assistance functions performed by the driver assistance device 26 include one or more functions such as a collision damage mitigation function, a lane departure prevention (lane keeping assist) function, a straight-line driving assist function, and a rear side vehicle proximity warning (blind spot monitor) function. The collision damage mitigation function is a function that slows down the vehicle 1 to avoid a collision or reduce collision damage when there is a possibility of collision with an object in the direction of travel. To realize the above functions, the driver assistance device 26 is connected to a front camera 18, a rear camera that photographs the area behind the vehicle 1, and a radar unit that detects objects around the vehicle 1.

[0025] The automatic driving device 27 is a device that enables the vehicle 1 to perform automatic driving functions.

[0026] As described above, the processor 100 of the vehicle display device 23 functions as a risk indicator detection unit 101, a gaze detection unit 102, an eye detection unit 103, a driver state detection unit 104, a determination unit 105, a TTC calculation unit 106, a speaker control unit 107, and a display control unit 108.

[0027] [2-1. Risk Indicator Detection Unit] The risk indicator detection unit 101 detects risk indicators 2 present in front of the vehicle 1. Risk indicators 2 refer to indicators that may come into contact with the vehicle 1, such as other vehicles or pedestrians. Based on the image data of the captured image SG received from the front camera 18, the risk indicator detection unit 101 detects risk indicators 2 that appear in the captured image SG obtained by the front camera 18. The risk indicator detection unit 101 detects risk indicators 2 that appear in the captured image SG by performing pattern matching and color-based image processing on the captured image SG. The data necessary for detecting risk indicators 2 (for example, shape data and color data) is stored in the memory 110 for each type of risk indicator 2 to be detected.

[0028] Furthermore, the risk indicator detection unit 101 detects the position of the detected risk indicator 2. More specifically, the risk indicator detection unit 101 detects the relative position of the risk indicator 2 with respect to the vehicle 1 when the vehicle 1 is viewed from above. The risk indicator detection unit 101 detects the relative position of the detected risk indicator 2 based on at least one of the detection results of the position detection device 24 and the image SG captured by the front camera 18. If the detected risk indicator 2 is another vehicle, and the vehicle display device 23 is connected to a vehicle-to-vehicle communication device and a GNSS unit, the risk indicator detection unit 101 may detect the relative position of the detected risk indicator 2 based on the position of the other vehicle received by the vehicle-to-vehicle communication device and the position of vehicle 1 received by the GNSS unit.

[0029] In addition to the front camera 18, vehicle-to-vehicle communication device, and GNSS unit, the risk indicator detection unit 101 may also use V2X (vehicle-to-infrastructure or pedestrian-to-pedestrian communication, etc.) to detect risk indicators 2 in the captured image SG and to detect the relative position of risk indicators 2.

[0030] When the risk indicator detection unit 101 detects a risk indicator 2, it outputs data indicating the relative position of the detected risk indicator 2 with respect to the vehicle 1 to the determination unit 105 and the TTC calculation unit 106. Furthermore, when the risk indicator detection unit 101 detects a risk indicator 2, it outputs data indicating the position of the detected risk indicator 2 in the captured image SG to the speaker control unit 107 and the display control unit 108.

[0031] [2-2. Eye-tracking unit] The gaze detection unit 102 detects the direction of the driver P's gaze. The gaze detection unit 102 detects the direction of the driver P's gaze based on the image data of the captured image received from the driver monitoring camera 22. The gaze detection unit 102 detects the driver P's eyes from the captured image obtained from the driver monitoring camera 22 using pattern matching, color, etc., and detects the direction the detected eyes are facing as the direction of the gaze. The data necessary for eye detection (data on eye shape and color) is stored in the memory 110.

[0032] When the gaze detection unit 102 detects the direction of the driver P's gaze, it outputs data indicating the detected direction of the gaze to the display control unit 108.

[0033] [2-3. Visual Detection Unit] The eye detection unit 103 detects the eyes of the driver P seated in the driver's seat 10A. The eye detection unit 103 detects the eyes of the driver P based on the image data of the captured image received from the driver monitoring camera 22. The eye detection unit 103 detects the head HD from the captured image obtained from the driver monitoring camera 22 using pattern matching, color, etc. Next, the eye detection unit 103 detects the position of the eyes in the captured image using pattern matching, color, etc. Then, the eye detection unit 103 detects the position of the eyes in the up, down, left, and right directions of the vehicle 1 based on the position of the eyes in the captured image. The position of the eyes in the captured image and the position of the eyes in the up and down direction of the vehicle 1 are determined by prior tests and simulations and stored as data in the memory 110.

[0034] [2-4. Driver Status Detection Unit] The driver state detection unit 104 detects whether the driver P seated in the driver's seat 10A is in a normal or abnormal state. The driver state detection unit 104 detects whether the driver P is in a normal or abnormal state based on the image data of the captured image received from the driver monitoring camera 22.

[0035] More specifically, the driver state detection unit 104 detects the driver P's face from the captured image obtained by the driver monitoring camera 22 using pattern matching or the like. Next, the driver state detection unit 104 determines whether the driver P's face detected from the captured image is the face of a normal driver P or the face of a driver P in an abnormal state. For example, the driver state detection unit 104 detects that the face of driver P detected from the captured image is in an abnormal state if it shows the driver P with their eyes closed for a predetermined period of time, or if it shows an angry or panicked expression. On the other hand, for example, the driver state detection unit 104 detects that the face of driver P detected from the captured image is in a normal state if it does not show the driver P with their eyes closed for a predetermined period of time, is not angry, or is not panicked. The detection of what kind of face it is is performed based on pattern matching or color. The driver state detection unit 104 detects that driver P is in a normal state if the face of driver P detected from the captured image is the face of driver P when he is in a normal state. On the other hand, the driver state detection unit 104 detects that driver P is in an abnormal state if the face of driver P detected from the captured image is the face of driver P when he is in an abnormal state.

[0036] Furthermore, if driver P is wearing a wearable device, the driver state detection unit 104 may receive biometric data of driver P from the wearable device and detect whether driver P is in a normal or abnormal state based on the received biometric data.

[0037] [2-5. Judgment section] The determination unit 105 determines whether or not the visibility-reduced image VG, which will be described later, can be displayed. The following are several examples of the determination methods of the determination unit 105.

[0038] [2-5-1. Judgment method 1] In determination method 1, the determination unit 105 determines whether or not to display the visibility reduction image VG based on information about the road on which the vehicle 1 is traveling. For example, if the road on which the vehicle 1 is traveling is a highway, the determination unit 105 determines that the visibility reduction image VG cannot be displayed, and if the road on which the vehicle 1 is traveling is a general road, it determines that the visibility reduction image VG can be displayed. As will be revealed later, the vehicle display device 23 increases the likelihood that the driver P can grasp the risk indicator 2 by displaying the visibility reduction image VG. Therefore, depending on the location of the risk indicator 2, the driver P may become distracted. Accordingly, if the vehicle 1 is estimated to be traveling at a high speed on a highway, the determination unit 105 determines that the visibility reduction image VG cannot be displayed, and if the vehicle 1 is estimated to be traveling at a low speed on a general road, it determines that the visibility reduction image VG can be displayed.

[0039] The determination unit 105 may obtain information about the road on which vehicle 1 is traveling from the map data stored in the memory 110, or it may obtain information about the road on which vehicle 1 is traveling from an external server by communicating with the external server.

[0040] [2-5-2. Judgment method 2] In determination method 2, the determination unit 105 determines whether or not to display the reduced visibility image VG based on the time until contact with the risk indicator 2. Hereinafter, the time until contact with the risk indicator 2 will be appropriately expressed as TTC (Time to Collision). The determination unit 105 calculates the TTC when determining whether or not to display the reduced visibility image VG.

[0041] Now, let's explain how to calculate TTC. The determination unit 105 calculates the distance between vehicle 1 and risk indicator 2, and the relative speed between vehicle 1 and risk indicator 2, when calculating TTC. For example, the determination unit 105 calculates the distance between the vehicle 1 and the risk indicator 2 based on the relative position data received from the risk indicator detection unit 101. Furthermore, for example, the determination unit 105 calculates the relative speed between the vehicle 1 and the risk indicator 2 based on the multiple relative position data received from the risk indicator detection unit 101 and the detection result of the vehicle speed sensor 25. Furthermore, for example, suppose that a vehicle-to-vehicle communication device and a GNSS unit are connected to the vehicle display device 23, and the risk indicator 2 detected by the risk indicator detection unit 101 is another vehicle. In this case, the determination unit 105 calculates the relative speed between vehicle 1 and risk indicator 2, and the distance between vehicle 1 and risk indicator 2, based on the speed of vehicle 1 detected by the vehicle speed sensor 25, the position of vehicle 1 received by the GNSS unit, and the position and speed of the other vehicle received by the vehicle-to-vehicle communication device. The determination unit 105 calculates the distance between vehicle 1 and risk indicator 2, and the relative speed between vehicle 1 and risk indicator 2, and then calculates the TTC by dividing the calculated distance between vehicle 1 and the calculated relative speed.

[0042] The determination unit 105 determines that the reduced visibility image VG can be displayed if the calculated TTC is below a predetermined value (for example, 7 seconds), and determines that the reduced visibility image VG cannot be displayed if the calculated TTC is equal to or greater than the predetermined value. Note that the predetermined value being 7 seconds is merely an example. This predetermined value is not limited to 7 seconds; it may be greater than 7 seconds or less than 7 seconds. This predetermined value is appropriately determined through prior testing or simulation.

[0043] [2-5-3. Judgment method 3] In the determination method 3, the determination unit 105 determines whether or not to display the reduced visibility image VG based on the distance from the driver P's viewpoint P1 on the windshield 20 to the risk indicator 2 (hereinafter referred to as the viewpoint indicator distance).

[0044] The determination unit 105 calculates the distance between viewpoint indicators when making this determination. Now, referring to Figure 4, we will explain how to calculate the distance between viewpoint indicators. Figure 4 is a diagram illustrating the calculation of the distance between viewpoint indicators.

[0045] The determination unit 105 detects the driver P's viewpoint P1 on the windshield 20 based on the direction of the gaze indicated by the data received from the gaze detection unit 102. For example, if the memory 110 stores data that associates the direction of the driver P's gaze with the driver P's viewpoint P1 on the windshield 20, the determination unit 105 refers to this data to detect the driver P's viewpoint P1 on the windshield 20. The determination unit 105 then expands a coordinate system that defines the shape, size, and up / down / left / right directions of the displayable area A1 into the memory 110, and determines the viewpoint P1 by referring to the expanded coordinate system.

[0046] Next, the determination unit 105 determines the risk indicator position P2. The risk indicator position P2 is the position of the risk indicator 2 on the windshield 20 as seen from the driver P. The determination unit 105 expands the coordinate system, which defines the shape, size, and up / down / left / right directions of the displayable area A1, into the memory 110, and determines the risk indicator position P2 by referring to the expanded coordinate system.

[0047] The determination unit 105 determines the risk indicator position P2 in the vertical direction of the displayable area A1 (hereinafter referred to as "first risk indicator position P2-1" with the designation "P2-1"). The vertical direction of the displayable area A1 corresponds to the vertical direction of the windshield 20 and the short-side direction of the displayable area A1. Furthermore, in determining the risk indicator position P2, the determination unit 105 determines the risk indicator position P2 in the left-right direction of the displayable area A1 (hereinafter referred to as "second risk indicator position P2-2" with the designation "P2-2"). The left-right direction of the displayable area A1 corresponds to the left-right direction of the windshield 20 and the longitudinal direction of the displayable area A1.

[0048] First, let's explain how to determine the position of the first risk indicator, P2-1. The determination unit 105 obtains the position of risk indicator 2 in the vertical direction of the captured image SG from the data output by the risk indicator detection unit 101. The vertical direction of the captured image SG corresponds to the vertical direction of the scene captured in the captured image SG. Next, the determination unit 105 converts the obtained position of risk indicator 2 into a position in the vertical direction of the displayable area A1, and determines the converted position as the first risk indicator position P2-1. The relationship between the position in the vertical direction of the captured image SG and the position in the vertical direction of the displayable area A1 is determined by prior simulations, etc., and is stored as data in the memory 110.

[0049] Next, we will explain the determination of the second risk indicator position P2-2. The determination unit 105 obtains the position of risk indicator 2 in the left-right direction of the captured image SG from the data output by the risk indicator detection unit 101. The left-right direction of the captured image SG is perpendicular to the up-down direction of the captured image SG. Next, the determination unit 105 converts the obtained position of risk indicator 2 into a position in the left-right direction of the displayable area A1. The relationship between the position in the left-right direction of the captured image SG and the position in the left-right direction of the displayable area A1 is determined by prior tests or simulations and stored as data in the memory 110. The determination unit 105 converts the position in the left-right direction of the displayable area A1, and then corrects the converted position in the left-right direction of the displayable area A1 based on the eye position detected by the eye detection unit 103. For example, if the eye position is to the left of a predetermined reference point in the left-right direction of the vehicle 1, the determination unit 105 corrects the converted position to the left according to the distance between the predetermined reference point and the eye position in the left-right direction. Also, for example, if the eye position is to the right of a predetermined reference point in the left-right direction of the vehicle 1, the determination unit 105 corrects the converted position to the right according to the distance between the predetermined reference point and the eye position. The determination unit 105 then determines the corrected position to be the second risk indicator position P2-2.

[0050] Once the determination unit 105 has determined the first risk indicator position P2-1 and the second risk indicator position P2-2, it determines the position defined by the first risk indicator position P2-1 and the second risk indicator position P2-2 as the risk indicator position P2.

[0051] The determination unit 105 determines the viewpoint P1 and the risk indicator position P2, and calculates the distance L2 between the viewpoint P1 and the risk indicator position P2 on the windshield 20 as the viewpoint indicator distance. The determination unit 105 calculates the viewpoint indicator distance by finding the distance between the viewpoint P1 and the risk indicator position P2 in a straight line in the coordinate system expanded in the memory 110, and converting it to the distance on the windshield 20.

[0052] The determination unit 105 calculates the distance between viewpoint indicators and determines whether the distance between viewpoint indicators is greater than or equal to a predetermined distance. If the distance between viewpoint indicators is less than or equal to the predetermined distance, the determination unit 105 determines that the reduced visibility image VG cannot be displayed, and if the distance between viewpoint indicators is greater than the predetermined distance, it determines that the reduced visibility image VG can be displayed.

[0053] [2-5-4. Judgment method 4] In determination method 4, the determination unit 105 determines whether or not to display the visibility-reduced image VG based on the driver P's state. If the driver state detection unit 104 determines that the driver P is in a normal state, the determination unit 105 determines that the visibility-reduced image VG can be displayed. On the other hand, if the driver state detection unit 104 determines that the driver P is in an abnormal state, the determination unit 105 determines that the visibility-reduced image VG cannot be displayed.

[0054] [2-5-5. Judgment method 5] In determination method 5, the determination unit 105 determines whether or not the visibility-reduced image VG can be displayed based on whether or not the vehicle 1 has a driver assistance function. If the vehicle 1 has a driver assistance function, the determination unit 105 determines that the visibility-reduced image VG can be displayed. On the other hand, if the vehicle 1 does not have a driver assistance function, the determination unit 105 determines that the visibility-reduced image VG cannot be displayed. Whether or not the vehicle 1 has a driver assistance function is stored as data in the memory 110. The determination unit 105 then refers to this data stored in the memory 110 to determine whether or not the visibility-reduced image VG can be displayed.

[0055] As described above, the determination methods of the determination unit 105 have been illustrated. The determination unit 105 may determine whether or not to display the low visibility image VG using any of the determination methods 1 to 5, or it may determine whether or not to display the low visibility image VG by combining any of the processes of determination methods 1 to 5.

[0056] [2-6.TTC calculation part] The TTC calculation unit 106 calculates the TTC. The TTC calculation unit 106 calculates the TTC using the same calculation method as the determination unit 105.

[0057] [2-7. Speaker Control Unit] The speaker control unit 107 operates the speaker 17 and outputs sound to the driver P.

[0058] [2-8. Display Control Unit] The display control unit 108 controls the operation of the HUD 19 to temporarily display a visibility-reducing image VG on the windshield 20. The visibility-reducing image VG is an image that reduces the visibility of the driver P through the windshield 20. The display control unit 108 displays the visibility-reducing image VG by performing the following processing.

[0059] The processing of the display control unit 108 will be explained with reference to Figure 5. Figure 5 is a diagram illustrating the processing of the display control unit 108.

[0060] The display control unit 108 obtains the upper end position 2J and the lower end position 2K of the risk indicator 2 in the captured image SG from the data detected by the risk indicator detection unit 101. The display control unit 108 also obtains the left end position 2S and the right end position 2U of the risk indicator 2 in the captured image SG from the data detected by the risk indicator detection unit 101.

[0061] Next, the display control unit 108 converts the acquired upper end position 2J into a position in the vertical direction of the displayable area A1. This converted position is denoted as "KJ" and is called the converted upper end position KJ. Furthermore, the display control unit 108 converts the acquired lower end position 2K into a position in the vertical direction of the displayable area A1. This converted position is denoted as "KK" and is called the converted lower end position KK. Furthermore, the display control unit 108 converts the acquired leftmost position 2S into a position in the left-right direction of the displayable area A1. This converted position is denoted as "KS" and is called the converted leftmost position KS. Furthermore, the display control unit 108 converts the acquired rightmost position 2U into a position in the left-right direction of the displayable area A1. This converted position is denoted with the code "KU" and is called the converted rightmost position KU.

[0062] The relationship between the position of the captured image SG in the vertical, horizontal, and vertical directions and the position of the displayable area A1 in the vertical, horizontal, and vertical directions is determined by prior simulations and stored as data in the memory 110. The display control unit 108 then refers to this data stored in the memory 110 and converts the four positions obtained from the captured image SG.

[0063] Next, the display control unit 108 corrects the converted upper end position KJ, converted lower end position KK, converted left end position KS, and converted right end position KU based on the eye position detected by the eye detection unit 103. The display control unit 108 then expands the coordinate system that defines the shape, size, and up / down / left / right directions of the displayable area A1 into the memory 110, plots the converted upper end position KJ, converted lower end position KK, converted left end position KS, and converted right end position KU on the expanded coordinate system, and then corrects these four positions.

[0064] For example, if the eye position is above a predetermined reference point in the vertical direction of the vehicle 1, the display control unit 108 corrects the converted upper end position KJ and converted lower end position KK in the vertical direction of the displayable area A1 downward according to the distance between the predetermined reference point and the eye position. Furthermore, for example, if the eye position is below a predetermined reference point in the vertical direction of the vehicle 1, the display control unit 108 corrects the converted upper end position KJ and converted lower end position KK in the vertical direction of the displayable area A1 upward according to the distance between the predetermined reference point and the eye position. Furthermore, for example, if the eye position is to the left of a predetermined reference point in the left-right direction of the vehicle 1, the display control unit 108 corrects the converted left end position KS and converted right end position KU in the left-right direction of the displayable area A1 to the left according to the distance between the predetermined reference point and the eye position. Furthermore, for example, if the eye position is to the right of a predetermined reference point in the left-right direction of the vehicle 1, the display control unit 108 corrects the converted left end position KS and converted right end position KU in the left-right direction of the displayable area A1 to the right according to the distance between the predetermined reference point and the eye position.

[0065] Hereafter, the corrected upper end position KJ will be denoted as "HJ" and referred to as the corrected upper end position HJ. Similarly, the corrected lower end position KK will be denoted as "HK" and referred to as the corrected lower end position HK. Similarly, the corrected left end position KS will be denoted as "HS" and referred to as the corrected left end position HS. Similarly, the corrected right end position KU will be denoted as "HU" and referred to as the corrected right end position HU.

[0066] Next, the display control unit 108 determines the risk indicator range R1. The risk indicator range R1 is the range on the windshield 20 that corresponds to the risk indicator 2. The display control unit 108 then expands the coordinate system that defines the shape, size, and up / down / left / right directions of the displayable area A1 into the memory 110, plots the corrected upper end position HJ, corrected lower end position HK, corrected left end position HS, and corrected right end position HU on the expanded coordinate system, and then determines the risk indicator range R1.

[0067] The display control unit 108 determines the risk indicator range R1 as a circular area where at least one of the corrected upper end position HJ, corrected lower end position HK, corrected right end position HU, and corrected left end position HS is located on the circumference and these four positions are included within the circumference.

[0068] The shape of the risk indicator range R1 is not limited to a circle. For example, the display control unit 108 may define the risk indicator range R1 as a rectangle formed by connecting the corrected upper end position HJ, the corrected lower end position HK, the corrected right end position HU, and the corrected left end position HS with straight lines.

[0069] Furthermore, the risk indicator range R1 does not have to be a range where at least one of the corrected upper limit position HJ, corrected lower limit position HK, corrected right limit position HU, and corrected left limit position HS is located on the circumference. For example, the risk indicator range R1 may be a range where all of the corrected upper limit position HJ, corrected lower limit position HK, corrected right limit position HU, and corrected left limit position HS are included within the circumference.

[0070] As described above, the display control unit 108 can determine the risk indicator range R1 by determining the range based on the position and size of the risk indicator 2 and the position of the driver P's eyes in the vehicle 1.

[0071] The display control unit 108 may also determine the risk indicator range R1 by taking into account information about the road on which vehicle 1 is traveling. In this case, the display control unit 108 obtains information about the road on which vehicle 1 is traveling from map data stored in memory 110 or from an external server, and determines the risk indicator range R1. For example, if the road on which the vehicle 1 travels is a public road, the display control unit 108 may determine that at least one of the four positions is located on the circumference of the aforementioned risk indicator range R1. If the vehicle 1 is traveling on a highway, the risk indicator range R1 may be determined to have a larger radius than the range for the case of a public road. Furthermore, for example, if the width of the road on which the vehicle 1 is traveling is greater than or equal to a predetermined value, the display control unit 108 may determine at least one of the four positions to be the aforementioned risk indicator range R1 located on the circumference, and if the width of the road on which the vehicle 1 is traveling is less than the predetermined value, it may determine the risk indicator range R1 to be a range with a larger radius than when the road width is greater than or equal to the predetermined value.

[0072] Furthermore, if the risk indicator 2 detected by the risk indicator detection unit 101 includes both people and non-people objects (for example, a motorcycle and its driver), the display control unit 108 determines the risk indicator range R1, which includes people or non-people objects, based on information about the road on which vehicle 1 is traveling. In this case, the display control unit 108 obtains information about the road on which vehicle 1 is traveling from map data stored in memory 110 or from an external server to determine the risk indicator range R1. In this case, the display control unit 108 also obtains four positions from the captured image SG with respect to people or non-people objects to determine the risk indicator range R1. For example, the display control unit 108 determines the risk indicator range R1 to include people if the road on which vehicle 1 is traveling is a public road, and determines the risk indicator range R1 to include objects other than people if the road on which vehicle 1 is traveling is a highway.

[0073] When the display control unit 108 determines the risk indicator range R1, it displays the reduced visibility image VG in the area of ​​the displayable area A1 other than the determined risk indicator range R1.

[0074] Figure 6 shows an example of a visually impaired image (VG). As described above, the visibility-reducing image VG is an image that reduces the visibility of the driver P through the windshield 20. The visibility-reducing image VG is displayed in the displayable area A1 outside the risk indicator range R1. The visibility-reducing image VG is an image with lower transmittance than the windshield 20. The transmittance of the visibility-reducing image VG is set to a level that allows the driver P to see the scene through the windshield 20 even when viewing the visibility-reducing image VG.

[0075] As described above, the display control unit 108 temporarily displays the visibility-reducing image VG on the windshield 20. This temporarily emphasizes the risk indicator 2 on the windshield 20, and stimulates the driver P regarding the risk indicator 2 for such a short time that the driver P is unaware of it. In other words, it is possible to exert a subliminal effect on the driver P regarding the risk indicator 2. Thus, the annoyance of having an image displayed on the windshield 20 can be suppressed, and the likelihood of the driver P being able to grasp the risk indicator 2 can be increased.

[0076] [2. Operation of the vehicle display device] Next, the operation of the vehicle display device 23 according to this embodiment will be described. Figure 7 is a flowchart showing the operation of the vehicle display device 23.

[0077] The risk indicator detection unit 101 detects a risk indicator 2 located in front of the vehicle 1 (step S1). Step S1 corresponds to the "detection step".

[0078] The determination unit 105 determines whether or not risk indicator 2 was detected in step S1 (step S2). The determination in step S2 is made by whether or not data is received from the risk indicator detection unit 101.

[0079] If the determination unit 105 determines that risk indicator 2 is not detected (step S2: NO), the processor 100 returns to step S1 and performs the process of step S1 again.

[0080] On the other hand, if it is determined that risk indicator 2 has been detected (step S2: YES), the determination unit 105 determines whether the visibility-reduced image VG can be displayed or not (step S3).

[0081] If the determination unit 105 determines that the visibility-reduced image VG can be displayed (step S3: displayable), the TTC calculation unit 106 calculates the TTC with respect to the risk indicator 2 detected by the risk indicator detection unit 101 (step S4).

[0082] Next, the display control unit 108 determines whether the TTC calculated in step S4 is greater than or equal to a predetermined value (step S5). This predetermined value is set to a value greater than the predetermined value used by the determination unit 105 in the determination method 2, for example, 8 seconds.

[0083] If the display control unit 108 determines that the TTC calculated in step S4 is greater than or equal to a predetermined value (step S5: YES), it temporarily displays the visibility-reduced image VG (step S6). Step S6 corresponds to the "display step".

[0084] In step S6, the display control unit 108 displays the visibility-reduced image VG for a first time. The first time is a shorter period than the second time, which will be described later, for example, 0.03 seconds. Note that this example of the first time is merely an example and is not limited to 0.03 seconds. The first time only needs to be shorter than the second time and can be considered temporary (for example, 0.5 seconds or less).

[0085] Next, the gaze detection unit 102 detects the direction of the driver P's gaze (step S7).

[0086] Next, the display control unit 108 determines whether or not the driver P's gaze is directed towards the risk indicator 2 (step S8).

[0087] In step S8, the display control unit 108 makes a determination based on the direction of the line of sight detected in step S7 and the position of the risk indicator 2 in the captured image SG indicated by the data received from the risk indicator detection unit 101.

[0088] If the display control unit 108 determines that the driver P's gaze is directed towards the risk indicator 2 (step S8: YES), the processor 100 terminates this process.

[0089] On the other hand, if the display control unit 108 determines that the driver P's gaze was not directed towards the risk indicator 2 (step S8: NO), it temporarily displays the reduced visibility image VG (step S9). Step S9 corresponds to the "display step".

[0090] In step S9, the display control unit 108 displays the low-visibility image VG for a second period of time. The second period is longer than the first period, which will be described later, and is, for example, 0.5 seconds. Note that this example of the second period is merely an example and is not limited to 0.5 seconds. The second period only needs to be longer than the first period and should be considered temporary (for example, 0.5 seconds or less). Furthermore, in step S9, the display control unit 108 displays a reduced visibility image VG that is less visible to the driver P than the reduced visibility image VG displayed in step S6.

[0091] Returning to the explanation of step S5, if the display control unit 108 determines that the TTC calculated in step S4 is below a predetermined value (step S5: NO), it determines whether or not vehicle 1 has an automatic driving function (step S10).

[0092] Step S10 will be described in detail. Whether or not vehicle 1 has an autonomous driving function is stored as data in memory 110. The display control unit 108 then refers to the data stored in memory 110 to determine whether or not vehicle 1 has an autonomous driving function.

[0093] If the system determines that vehicle 1 has an autonomous driving function (step S10: YES), the display control unit 108 transmits an autonomous driving start instruction to the autonomous driving device 27 to start autonomous driving (step S11). As a result, the display control unit 108 enables the autonomous driving function of vehicle 1.

[0094] Next, the processor 100 moves the process to step S6 and executes the process of moving to step S6.

[0095] On the other hand, if it is determined that vehicle 1 does not have an autonomous driving function (step S10: NO), the display control unit 108 temporarily displays a reduced visibility image VG (step S12). In step S12, the display control unit 108 displays the reduced visibility image VG for a period of 1 hour. Step S12 corresponds to the "display step".

[0096] Returning to the explanation of step S3, if the determination unit 105 determines that the visibility-reduced image VG cannot be displayed (step S3: display impossible), the display control unit 108 determines whether or not the vehicle 1 has an automatic driving function (step S13). The determination in step S13 is performed using the same method as the determination in step S10.

[0097] If the display control unit 108 determines that vehicle 1 has an autonomous driving function (step S13: YES), the processor 100 moves the process to step S6 and executes the processes from step S6 onward.

[0098] On the other hand, if the display control unit 108 determines that vehicle 1 does not have an autonomous driving function (step S13: NO), the speaker control unit 107 outputs sound through speaker 17 (step S14).

[0099] Step S14 will be described in detail. The speaker control unit 107 selects a speaker 17 to output sound based on the position of the risk indicator 2 in the captured image SG indicated by the data received from the risk indicator detection unit 101. For example, if the position of the risk indicator 2 in the captured image SG is to the left of the range that can be considered the center in the left-right direction of the captured image SG, the speaker control unit 107 selects speaker 14 as the speaker 17 to output sound. Also, for example, if the position of the risk indicator 2 in the captured image SG is within the range that can be considered the center in the left-right direction of the captured image SG, the speaker control unit 107 selects speakers 14 and 15 as the speakers 17 to output sound. For example, if the position of the risk indicator 2 in the captured image SG is to the right of the range that can be considered the center in the left-right direction of the captured image SG, the speaker control unit 107 selects speaker 15 as the speaker 17 to output sound. Next, the speaker control unit 107 outputs sound from the selected speaker 17. Furthermore, if sound such as content was being output from speaker 17 when step S14 is performed, the speaker control unit 107 will erase the sound of the content and output sound through the selected speaker 17.

[0100] [3. Other Embodiments] The embodiments described above are merely examples and can be modified and applied as needed.

[0101] In the embodiment described above, a speaker 17 was used as an example of a "stimulus output device," and sound was output as the "stimulus." In other words, in the embodiment described above, if the determination unit 105 determines that the visibility-reduced image VG cannot be displayed, and the display control unit 108 does not display the visibility-reduced image VG, the speaker 17 outputs sound to the driver P. However, the type of "stimulus" applied to the driver P in this case is not limited to sound; for example, it could be vibration. For example, in another embodiment, a vibration output device that vibrates the steering wheel or the driver's seat 10A is connected to the vehicle display device 23, and if the determination unit 105 determines that the visibility-reduced image VG cannot be displayed, and the display control unit 108 does not display the visibility-reduced image VG, vibration may be applied to the driver P by the vibration output device.

[0102] In another embodiment, if the TTC calculated by the TTC calculation unit 106 falls below a predetermined value, the display control unit 108 may not display the reduced visibility image VG on the windshield 20, but may instead highlight the risk indicator range R1 on the windshield 20. In this other embodiment, the display control unit 108 may highlight the risk indicator range R1 by, for example, displaying the entire range R1 in a predetermined color, or by displaying the edges of the risk indicator range R1 in a predetermined color. Furthermore, in this other embodiment, regardless of the determination result of the determination unit 105, the display control unit 108 may highlight the risk indicator range R1 on the windshield 20 if the TTC calculated by the TTC calculation unit 106 falls below a predetermined value. It is preferable that this predetermined value is set to a value lower than the predetermined value compared in step S5.

[0103] In the embodiment described above, a four-wheeled automobile vehicle 1 was used as an example of a "vehicle," but the number of wheels is not limited to four as long as the "vehicle" has a windshield 20.

[0104] In the embodiment described above, the HUD 19 is used to display the image on the windshield 20. However, the means for displaying the image on the windshield 20 can be any means for displaying a virtual image on the windshield 20, and is not limited to the HUD 19. For example, it could be a display means such as an LED (Light Emitting Diode).

[0105] The processor 100 may consist of multiple processors or a single processor. The processor 100 may also be hardware programmed to implement the functions described above. In this case, the processor 100 may consist of, for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0106] Furthermore, the configuration of each part of Vehicle 1 shown in Figure 3 is merely an example, and the specific implementation is not particularly limited. In other words, it is not necessarily required that hardware corresponding to each part be implemented individually; it is certainly possible to configure a system where a single processor executes a program to realize the functions of each part. Also, in the embodiments described above, some of the functions realized by software may be implemented as hardware, or conversely, some of the functions realized by hardware may be implemented as software.

[0107] Furthermore, the operation steps shown in Figure 7 are divided according to the main processing content, and the present invention is not limited by the way the processing units are divided or their names. Depending on the processing content, it may be further divided into more steps. Alternatively, it may be divided so that one step unit includes even more processing. Also, the order of the steps may be changed as appropriate, as long as it does not impede the spirit of the present invention.

[0108] Furthermore, when the control method for the vehicle display device 23 described above is implemented using the processor 100, the program to be executed by the processor 100 can be configured as a recording medium or a transmission medium for transmitting this program. In other words, the control program 111 can also be implemented by recording it on a portable information recording medium. Examples of information recording media include magnetic recording media such as hard disks, optical recording media such as CDs, and semiconductor storage devices such as USB (Universal Serial Bus) memory and SSDs (Solid State Drives), but other recording media can also be used.

[0109] The above embodiment supports the following configuration.

[0110] (Composition 1) A vehicle display device comprising: a detection unit for detecting risk indicators located in front of a vehicle and potentially in contact with the vehicle; and a display control unit for displaying an image on the windshield of the vehicle, wherein the display control unit temporarily displays a visibility-reducing image on the windshield in an area other than the risk indicator range corresponding to the risk indicator detected by the detection unit, thereby reducing the visibility of the vehicle's driver. According to the vehicle display device of Configuration 1, risk indicators can be temporarily highlighted on the windshield, providing the driver with a brief alert about the risk indicators. Therefore, the inconvenience of having images displayed on the windshield can be reduced, and the likelihood of the driver understanding the risk indicators can be increased.

[0111] (Configuration 2) The vehicle display device according to Configuration 1, further comprising a determination unit for determining whether or not to display the reduced visibility image, wherein the determination unit determines whether or not to display the reduced visibility image based on at least one of the following: information on the road on which the vehicle is traveling, the time until contact with the risk indicator, the distance from the driver's viewpoint on the windshield to the risk indicator, the driver's condition, and the presence or absence of the vehicle's driver assistance function. Depending on the road the vehicle is traveling on, it may be preferable not to display the reduced visibility image. Also, depending on the time until contact with the risk indicator, it may be preferable not to display the reduced visibility image. Also, depending on the distance between the driver's line of sight on the windshield and the risk indicator, it may be preferable not to display the reduced visibility image. Also, depending on the driver's condition, it may be preferable not to display the reduced visibility image. Also, depending on the presence or absence of driver assistance functions in the vehicle, it may be preferable not to display the reduced visibility image. Therefore, according to configuration 2, the reduced visibility image can be displayed in appropriate situations.

[0112] (Composition 3) The vehicle display device according to configuration 2, wherein the display control unit displays the reduced visibility image for a first hour if the determination unit determines that the reduced visibility image can be displayed, and if, after the display of the reduced visibility image in the first hour the driver's gaze is not directed toward the risk indicator, the reduced visibility image is displayed for a second hour, which is longer than the first hour. According to the vehicle display device of configuration 3, if the driver's gaze is not directed towards the risk indicator, the reduced visibility image is temporarily displayed again. Therefore, it is possible to further increase the likelihood that the driver can grasp the risk indicator while suppressing the unnecessary display of images on the windshield.

[0113] (Composition 4) The vehicle display device according to configuration 3, wherein the reduced visibility image displayed during the second time is an image that reduces the driver's visibility more than the reduced visibility image displayed during the first time. According to the vehicle display device of configuration 4, risk indicators can be emphasized more than the visibility-reduced image displayed the first time, thus further increasing the likelihood that the driver will be able to grasp the risk indicators.

[0114] (Composition 5) The vehicle display device according to any one of configurations 2 to 4, wherein the display control unit, when the determination unit determines that the reduced visibility image cannot be displayed, enables the automatic driving function if the vehicle has an automatic driving function and displays the reduced visibility image. According to the vehicle display device of configuration 5, compared to when the vehicle does not have an autonomous driving function, it becomes possible to display images with reduced visibility for many risk indicators, thereby increasing the likelihood that the driver can grasp a large number of risk indicators.

[0115] (Composition 6) The vehicle display device is connected to a stimulus output device that outputs stimuli other than display to the driver, and includes a stimulus control unit that controls the stimulus output device, wherein the determination unit determines that the reduced visibility image cannot be displayed, the display control unit does not display the reduced visibility image if the vehicle does not have an automatic driving function, and the stimulus control unit causes the stimulus output device to output the stimulus, as described in any one of configurations 2 to 5. According to the vehicle display device of configuration 6, by applying a stimulus, it is possible to increase the likelihood that the driver can grasp the risk indicators even when it is not possible to display images with reduced visibility.

[0116] (Composition 7) The vehicle display device according to any one of configurations 1 to 6, wherein the risk indicator range is a range based on the position and size of the risk indicator and the position of the driver's eyes in the vehicle. According to the vehicle display device of configuration 7, when the driver looks at the windshield, risk indicators can be appropriately and seamlessly highlighted to the driver, further increasing the likelihood that the driver will be able to grasp the risk indicators.

[0117] (Composition 8) The vehicle display device according to configuration 7, wherein the risk indicator range is a range based on information about the road on which the vehicle travels. According to the vehicle display device of configuration 8, the range of risk indicators can be set to include information about the road on which the vehicle is traveling, and risk indicators can be emphasized according to the road on which the vehicle is traveling. Therefore, the likelihood of the driver being able to grasp the risk indicators can be further increased.

[0118] (Composition 9) The vehicle display device according to configuration 8, wherein the display control unit, when the risk indicator includes both a person and an object other than a person, displays the reduced visibility image based on information about the road on which the vehicle is traveling, so that the person or the object is included in the range of the risk indicator. According to the vehicle display device of configuration 9, when the risk indicator includes both people and non-personal objects, the risk indicator can be emphasized according to the road on which the vehicle is traveling.

[0119] (Composition 10) The vehicle display device according to any one of configurations 1 to 9, wherein the display control unit highlights the risk indicator range when the time until the vehicle comes into contact with the risk indicator is less than or equal to a predetermined value. According to the vehicle display device of configuration 10, when there is a high probability of contact with a risk indicator, the likelihood of the driver being able to recognize the risk indicator can be increased, and the likelihood of avoiding contact between the risk indicator and the vehicle can be increased.

[0120] (Composition 11) A control method for a vehicle display device, comprising: a detection step of detecting a risk indicator that is located in front of the vehicle and may come into contact with the vehicle; and a display step of displaying an image on the windshield of the vehicle, wherein the display step temporarily displays a visibility-reducing image on the windshield that reduces the visibility of the vehicle's driver in an area other than the risk indicator range corresponding to the risk indicator detected in the detection step. The control method for the vehicle display device of configuration 11 produces the same effect as the vehicle display device of configuration 1.

[0121] (Composition 12) A processor is configured to function as a detection unit that detects risk indicators located in front of a vehicle and that may come into contact with the vehicle, and a display control unit that displays an image on the windshield of the vehicle, wherein the display control unit is configured to temporarily display a visibility-reducing image on the windshield in an area other than the risk indicator range corresponding to the risk indicator detected by the detection unit, the visibility of the vehicle to the driver of the vehicle being reduced. According to the program of configuration 11, the vehicle display device will have the same effect as the vehicle display device of configuration 1. [Explanation of Symbols]

[0122] 1...Vehicle, 2...Risk indicator, 2J...Upper end position, 2K...Lower end position, 2S...Left end position, 2U...Right end position, 10A...Driver's seat, 10B...Passenger seat, 10C...Rear right seat, 10D...Rear left seat, 12...Touch panel, 13,14,15,16,17...Speaker (stimulus output device), 18...Front camera, 19...HUD, 20...Windshield, 21...Instrument panel, 22...Driver monitoring camera, 23...Vehicle display device, 24...Position detection device, 25...Vehicle speed sensor, 26...Driving assistance device, 27...Autonomous driving device, 100...Processor, 101...Risk indicator detection unit (detection unit), 102...Gaze detection unit, 103...Eye detection unit, 104...Driver state detection 105...Determination unit, 106...TTC calculation unit, 107...Speaker control unit (stimulus control unit), 110...Memory, 111...Control program, HD...Head, HJ...Corrected upper end position, HK...Corrected lower end position, HS...Corrected left end position, HU...Corrected right end position, KJ...Converted upper end position, KK...Converted lower end position, KS...Converted left end position, KU...Converted right end position, L1...Dotted line, L2...Distance, P...Driver, P1...Viewpoint, P2-1...First risk indicator position, P2-2...Second risk indicator position, P2...Risk indicator position, R1...Risk indicator range, S1...Step (detection step), S6, S9, S12...Step (display step), SG...Captured image, VG...Image with reduced visibility.

Claims

1. A detection unit that detects risk indicators located in front of the vehicle and that may come into contact with the vehicle, The vehicle comprises a display control unit that displays an image on the windshield of the vehicle, The display control unit, In the windshield, a visibility-reducing image that reduces the visibility of the vehicle's driver is temporarily displayed in an area other than the risk indicator range corresponding to the risk indicator detected by the detection unit. Vehicle display device.

2. The system includes a determination unit that determines whether or not the aforementioned image with reduced visibility can be displayed, The determination unit determines whether or not to display the reduced visibility image based on at least one of the following: information about the road on which the vehicle is traveling, the time until contact with the risk indicator, the distance from the driver's viewpoint on the windshield to the risk indicator, the driver's condition, and the presence or absence of the vehicle's driver assistance functions. The vehicle display device according to claim 1.

3. The display control unit, If the determination unit determines that the reduced visibility image can be displayed, it displays the reduced visibility image for a first hour. If, after the display of the reduced visibility image during the first hour, the driver's gaze does not turn towards the risk indicator, the reduced visibility image will be displayed for a second hour, which is longer than the first hour. The vehicle display device according to claim 2.

4. The reduced visibility image displayed during the second time period is an image that reduces the driver's visibility even more than the reduced visibility image displayed during the first time period. The vehicle display device according to claim 3.

5. The display control unit, If the determination unit determines that the image with reduced visibility cannot be displayed, If the vehicle has an autonomous driving function, the autonomous driving function is enabled and the visibility-reduced image is displayed. The vehicle display device according to claim 2.

6. The vehicle display device is connected to a stimulus output device that outputs stimuli other than displays to the driver. The system includes a stimulus control unit that controls the stimulus output device, If the determination unit determines that the image with reduced visibility cannot be displayed, The display control unit shall not display the reduced visibility image if the vehicle does not have an autonomous driving function. The stimulus control unit causes the stimulus output device to output the stimulus. The vehicle display device according to claim 2.

7. The risk indicator range is a range based on the position and size of the risk indicator and the position of the driver's eyes in the vehicle. The vehicle display device according to any one of claims 1 to 6.

8. The aforementioned risk indicator range is based on information about the roads on which the vehicle travels. The vehicle display device according to claim 7.

9. The display control unit, If the risk indicator includes both people and objects other than people, the visibility-reduced image is displayed so that the person or object is included in the range of the risk indicator, based on information about the road on which the vehicle is traveling. The vehicle display device according to claim 8.

10. The display control unit, If the time until the vehicle comes into contact with the risk indicator is less than or equal to a predetermined value, the risk indicator range is highlighted. The vehicle display device according to any one of claims 1 to 6.

11. A detection step for detecting risk indicators that are located in front of the vehicle and that may come into contact with the vehicle, The step includes displaying an image on the windshield of the vehicle, The aforementioned display step is, In the windshield, a visibility-reducing image that reduces the visibility of the vehicle driver is temporarily displayed in an area other than the risk indicator range corresponding to the risk indicator detected in the detection step. A method for controlling a vehicle display device.

12. The processor, A detection unit that detects risk indicators located in front of the vehicle and that may come into contact with the vehicle, The aforementioned vehicle's windshield is configured to function as a display control unit that displays an image on the windshield. The display control unit, In the windshield, a visibility-reducing image that is less visible to the driver of the vehicle is temporarily displayed in an area other than the risk indicator range corresponding to the risk indicator detected by the detection unit. program.

Images