Head-up display

Abstract

To provide a head-up display excellent in information transmissibility.SOLUTION: A head-up display according to the present embodiment includes a display device that displays an image related to a virtual image displayed in a superimposed manner on an actual scene including a road surface 7 on which a vehicle travels, an image generation unit that generates an avoidance display 50 that is an image displayed on the display device to prompt avoidance of an obstacle 8 on the road surface 7 and indicates an avoidance route by dynamic display moving or extending from a near side to a far side in a traveling direction of the vehicle, and a display control unit that causes the image generation unit to generate the avoidance display 50 such that a display speed, which is a speed of movement or extension of the avoidance display 50, increases as a traveling speed of the vehicle increases.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a head-up display mounted in a vehicle. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a head-up display has been proposed that displays a virtual image superimposed on a real road surface to guide a vehicle driver along a route that avoids obstacles. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-012483 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable that the above-mentioned information for guiding the driver to the avoidance route be displayed in a manner that conveys even greater urgency, which is expected to further contribute to driving assistance.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to provide a head-up display with excellent information transmission capabilities. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the head-up display of the present disclosure comprises a display device that displays an image relating to a virtual image superimposed on an actual scene including the road surface on which the vehicle is traveling, an image generation unit that generates an avoidance display that is displayed on the display device and encourages the driver to avoid obstacles on the road surface, and that shows an avoidance route in a dynamic display that moves or extends from the front to the back in the direction of travel of the vehicle, and a display control unit that causes the image generation unit to generate the avoidance display so that the display speed, which is the speed at which the avoidance display moves or extends, increases as the traveling speed of the vehicle increases. [Effects of the Invention]

[0007] The head-up display device of the present disclosure has excellent information transmission ability. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of the system configuration of a head-up display according to an embodiment of the present invention. [Figure 2] FIG. 2 is an explanatory diagram showing a display area and an image (avoidance display) formed in front of the vehicle. [Figure 3] 10 is a flowchart illustrating an avoidance display control process. [Figure 4] FIG. 10 is an explanatory diagram for explaining a variable display speed. [Figure 5] FIG. 10 is an explanatory diagram showing the transition of the avoidance display when a variable display speed is applied. [Figure 6] FIG. 10 is an explanatory diagram showing the transition of the avoidance display when a variable display speed is applied. [Figure 7] FIG. 10 is an explanatory diagram showing the transition of the avoidance display when a variable display speed is applied. [Figure 8] FIG. 10 is an explanatory diagram showing the transition of the avoidance display when a variable display speed is applied. [Figure 9] FIG. 10 is an explanatory diagram showing a modified example of the avoidance display. [Figure 10] FIG. 10 is an explanatory diagram showing another modified example of the avoidance display. [Figure 11] FIG. 10 is an explanatory diagram showing yet another modified example of the avoidance display. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of a head-up display (hereinafter simply referred to as "HUD") according to the present disclosure will be described with reference to the accompanying drawings. The head-up display according to the present disclosure can be mounted on vehicles such as automobiles, motorcycles, agricultural machinery, and construction machinery. In this embodiment, an example in which the HUD is mounted on an automobile will be described.

[0010] FIG. 1 is a diagram showing an example of the system configuration of a HUD 10 according to this embodiment.

[0011] In the following description, "front," "rear," "up," "down," "right," and "left" follow the definitions of "Fr.", "Re.", "To.", "Bo.", "R," and "L" in Figures 1, 2, and 5 to 11. "Front" refers to the direction in which the vehicle 1 is traveling, and "rear" refers to the opposite direction to the traveling direction.

[0012] The HUD 10 is mounted in the instrument panel of the vehicle 1. The HUD 10 has a display 11, a plane mirror 12, a concave mirror 13, a housing 15, and a control unit 30. The HUD 10 reflects display light L associated with an image displayed on the display 11 by the plane mirror 12 and the concave mirror 13, which are relay optical systems, and irradiates the reflected light of the display light L on the windshield 3 of the vehicle 1. A viewer 4 (driver or passenger) of the vehicle 1 visually recognizes the reflected light of the display light L on the windshield 3 as a virtual image VI. As a result, the image is displayed in a virtual display area 20 that overlaps with the actual scene viewed by the viewer 4 through the windshield 3 (in front of the windshield 3).

[0013] FIG. 2 is an explanatory diagram showing a display area 20 formed in front of the vehicle 1 and an image (avoidance display 50).

[0014] The display area 20 is a rectangular area formed in the real space ahead of the vehicle 1. In this display area 20, the HUD 10 displays an image relating to the virtual image VI superimposed on a real scene including the road surface 7 on which the vehicle 1 is traveling. The display area 20 is inclined such that the upper portion is inclined toward the road surface 7, so that the virtual image VI is visually recognized as being displayed on the road surface 7. This allows the HUD 10 to continuously change the display distance of the virtual image VI within the display area 20 so that the lower portion (lower edge) of the display area 20 is on the near side of the road surface 7 (e.g., 0 m ahead of the vehicle) and the upper portion (upper edge) is on the far side of the road surface 7 (e.g., 50 m ahead of the vehicle).

[0015] The display 11 displays an image on, for example, a rectangular display surface, and emits display light L relating to the image toward the plane mirror 12. The display 11 is, for example, a TFT (Thin Film Transistor) type liquid crystal display or an organic EL (Electroluminescence) display. Note that the display 11 may also include a projector and a screen that forms the display surface.

[0016] The plane mirror 12 reflects the display light L emitted by the display device 11 toward the concave mirror 13. The concave mirror 13 further reflects the display light L reflected by the plane mirror 12 and emits it toward the windshield 3. The concave mirror 13 functions as a magnifying mirror, and magnifies the image displayed on the display device 11 and reflects it toward the windshield 3. In other words, the virtual image VI viewed by the viewer 4 is an enlarged version of the image displayed on the display device 11.

[0017] The housing 15 positions and supports the plane mirror 12 and the concave mirror 13 inside the housing 15. The housing 15 also positions and supports the display 11 and the control board on which the control unit 30 is mounted.

[0018] The control unit 30 performs processing mainly related to images displayed on the display 11, based on information and instructions acquired from each part of the vehicle 1, which will be described later. The control unit 30 is a microprocessor, a microcontroller, a graphics controller, an integrated circuit, or the like, and in this embodiment, particularly realizes a display control unit 31, an image generation unit 32, and a storage unit 33.

[0019] The display control unit 31 controls the display device 11 and the image generation unit 32 to generate and display a required image. The image generation unit 32 executes a drawing process for an image to be displayed on the display device 11 and generates the required image based on the control of the display control unit 31. The storage unit 33 stores programs and data required for the display control unit 31 and the image generation unit 32 to perform processing.

[0020] In addition to the HUD 10, the vehicle 1 includes an obstacle sensor 41, a GPS 42, and a vehicle ECU (Electronic Control Unit) 43. The obstacle sensor 41, the GPS 42, and the vehicle ECU 43 are connected to the control unit 30 via, for example, a CAN (Controller Area Network) bus 45.

[0021] The obstacle sensor 41 is a sensor that detects an obstacle 8 ahead of the vehicle 1, and is, for example, a sonar sensor, an ultrasonic sensor, a millimeter-wave radar, a camera, or the like. Alternatively, the obstacle 8 may be detected from information from a traffic information agency, such as traffic information issued by a road management organization or information obtained through inter-vehicle communication. The GPS 42 calculates the position of the vehicle 1 based on GPS signals received from an artificial satellite or the like. The vehicle ECU 43 acquires vehicle information necessary for the running of the vehicle 1, such as vehicle speed and engine RPM, from various sensors provided in the vehicle 1, and controls the operation of the vehicle 1.

[0022] Next, the display control process for the avoidance display 50 executed by the control unit 30 of the HUD 10 will be described in detail.

[0023] The HUD 10 displays an avoidance display 50, which is an image that prompts the driver to avoid an obstacle 8 on the road surface 7. As shown in FIG. 2, the avoidance display 50 is a dynamic display that moves from the front to the back in the traveling direction of the vehicle 1 along the road surface 7 in a perspective manner, and is an image that shows an avoidance route for the obstacle 8. Specifically, the avoidance display 50 first makes a figure (leading edge 50a) appear from the front, then moves to the back side, and similar figures appear one after another following the leading edge 50a, so that multiple arrow-shaped figures (multiple figures) pointing in the traveling direction are connected from the front to the back in the traveling direction.

[0024] The HUD 10 in this embodiment displays this avoidance display 50 so that the faster the traveling speed of the vehicle 1, the faster the display speed, which is the movement speed of the avoidance display 50, becomes. This makes it possible to convey to the viewer 4 the need to avoid the obstacle 8 with greater urgency. The avoidance display control process will be described in detail below.

[0025] 3 is a flowchart illustrating the avoidance display control process. The avoidance display control process is a process that is executed mainly based on the control of the control unit 30. The avoidance display control process is a process that is executed every time the HUD 10 displays the avoidance display 50, based on an instruction to display the avoidance display 50 that is supplied from the vehicle ECU 43 when the obstacle sensor 41 detects an obstacle 8, for example.

[0026] In step S1, the control unit 30 determines whether the vehicle 1 is traveling on a highway based on the position of the vehicle 1 supplied from the GPS 42. This step S1 is a step for determining whether the vehicle 1 is traveling at high speed. Therefore, the control unit 30 may determine whether the traveling speed of the vehicle 1 is higher than a predetermined speed, instead of whether the vehicle is traveling on a highway.

[0027] When the control unit 30 determines that the vehicle 1 is traveling on a highway (YES in step S1), in step S2, it determines to apply a variable display speed in which the display speed of the avoidance display 50 is variable within the display area 20. Here, Fig. 4 is an explanatory diagram for explaining the variable display speed as an example.

[0028] The avoidance display 50 is displayed through a first point P1 set from the front (bottom edge) to the back (top edge) of the display area 20, a second point P2 further back than the first point P1, and a third point P3 further back than the second point P2.

[0029] The variable display speed is determined in advance and stored in the storage unit 33, as shown in Fig. 4. The variable display speed is determined so that the display speed is faster when the leading edge 50a of the avoidance display 50 in the traveling direction is closer to you than when it is further away. The variable display speed is determined according to the movement distance (position) within the display area 20, i.e., the display distance of the virtual image VI from the vehicle 1.

[0030] Specifically, the variable display speeds are a first speed V1, a second speed V2, and a display speed that gradually decelerates from the first speed V1 to the second speed V2. The first speed V1 is a display speed that is applied when the leading edge 50a of the avoidance display 50 in the traveling direction travels from the nearest point P0 to the first point P1. The second speed V2 is a display speed that is applied when the leading edge 50a travels from the second point P2 to the farthest third point P3. The second speed V2 is slower than the first speed V1. The first speed V1 and the second speed V2 are determined in accordance with the traveling speed of the vehicle 1 so as to become faster as the traveling speed of the vehicle 1 increases.

[0031] In step S3, the display control unit 31 causes the image generation unit 32 to generate an image showing a required avoidance route so as to display the avoidance display 50 at the first speed V1. The display control unit 31 also causes the display device 11 to display the generated image. Here, FIGS. 5 to 8 are explanatory diagrams showing the transition of the avoidance display 50 to which the variable display speed is applied. As shown in FIG. 5, the display control unit 31 displays the avoidance display 50 so as to move from the foreground (point P0) to the background.

[0032] In step S4, the control unit 30 determines whether the leading end 50a of the avoidance display 50 in the traveling direction has reached the first point P1. If the control unit 30 determines that the leading end 50a has not reached the first point P1 (NO in step S4), the control unit 30 returns to step S3 and repeats the process until the leading end 50a reaches the first point P1. On the other hand, if the control unit 30 determines that the leading end 50a has reached the first point P1 (YES in step S4), in step S5, the display control unit 31 causes the image generation unit 32 to generate an image so as to display the avoidance display 50 while decelerating from the first speed V1 to the second speed V2. The display control unit 31 also causes the display 11 to display the generated image. As shown in FIG. 6, the display control unit 31 moves the avoidance display 50 further to the rear while decelerating from the first speed V1 to the second speed V2.

[0033] In step S6, the control unit 30 determines whether the leading end 50a of the avoidance display 50 in the traveling direction has reached the second point P2. If the control unit 30 determines that the leading end 50a has not reached the second point P2 (NO in step S6), the process returns to step S5 and repeats the process until the leading end 50a reaches the second point P2. On the other hand, if the control unit 30 determines that the leading end 50a has reached the second point P2 (YES in step S6), in step S7, the display control unit 31 causes the image generation unit 32 to generate an image so as to display the avoidance display 50 at the second speed V2. The display control unit 31 also causes the display 11 to display the generated image. As shown in FIGS. 7 and 8 , the display control unit 31 moves the avoidance display 50 further to the rear at the second speed V2. When the avoidance display 50 reaches the rear of the display area 20 (third point P3), the leading end 50a disappears from the display area 20.

[0034] In step S8, the control unit 30 determines whether the end 50b (the end opposite to the front end 50a) of the avoidance display 50 in the traveling direction has reached the third point P3. That is, the control unit 30 determines whether the avoidance display 50 has disappeared from the display area 20. If the control unit 30 determines that the end 50b has not reached the third point P3 (NO in step S8), the control unit 30 returns to step S7 and repeats the process until the end 50b reaches the third point P3. On the other hand, if the control unit 30 determines that the end 50b has reached the third point P3 (YES in step S8), in step S9, the control unit 30 determines whether or not to end the display of the avoidance display 50 as the vehicle 1 has avoided the obstacle 8 on the road surface 7.

[0035] If the control unit 30 determines that the display of the avoidance display 50 should not be ended yet (NO in step S9), the control unit 30 returns to step S3 and repeats the subsequent processes. That is, if the control unit 30 continues to display the avoidance display 50, after the end 50b of the avoidance display 50 passes, for example, the third point P3 and the avoidance display 50 disappears from the display area 20, the control unit 30 again displays the avoidance display 50 while moving it from the front (point P0) to the back. On the other hand, if the control unit 30 determines that the display of the avoidance display 50 should be ended (YES in step S9), the control unit 30 ends the avoidance display control process.

[0036] On the other hand, if the control unit 30 determines in step S1 that the vehicle 1 is not traveling on a highway but on a public road (NO in step S1), it decides in step S10 to apply a constant display speed at which the display speed of the avoidance display 50 is constant within the display area 20.

[0037] In step S11, the display control unit 31 causes the image generation unit 32 to generate an image showing a required avoidance route so as to display the avoidance display 50. The display control unit 31 also causes the display device 11 to display the generated image. At this time, the display control unit 31 uses a display speed of the avoidance display 50 that is determined in advance and stored in the storage unit 33, and that is determined to increase as the traveling speed increases. For example, when the traveling speed of the vehicle 1 is 40 km / h, the displayed speed is 22 m / s; when the traveling speed of the vehicle 1 is 60 km / h, the displayed speed is 25 m / s; and when the traveling speed of the vehicle 1 is 80 km / h, the displayed speed is 33 m / s.

[0038] In step S12, the control unit 30 determines whether the end 50b of the avoidance display 50 in the traveling direction has reached the third point P3 and the avoidance display 50 has disappeared from the display area 20. If the control unit 30 determines that the end 50b has not reached the third point P3 (NO in step S12), the control unit 30 returns to step S11 and repeats the process until the end 50b reaches the third point P3. On the other hand, if the control unit 30 determines that the end 50b has reached the third point P3 (YES in step S12), the control unit 30 determines in step S13 whether or not to end the display of the avoidance display 50 as the vehicle 1 has avoided the obstacle 8 on the road surface 7.

[0039] If the control unit 30 determines that the display of the avoidance display 50 should not be ended yet (NO in step S13), the control unit 30 returns to step S11 and repeats the subsequent processes. That is, if the control unit 30 continues to display the avoidance display 50, after the end 50b of the avoidance display 50 passes, for example, the third point P3 and the avoidance display 50 disappears from the display area 20, the control unit 30 again displays the avoidance display 50 while moving it from the front (point P0) to the back. On the other hand, if the control unit 30 determines that the display of the avoidance display 50 should be ended (YES in step S13), the control unit 30 ends the avoidance display control process.

[0040] The HUD 10 in this embodiment increases the display speed of the avoidance display 50 as the traveling speed of the vehicle 1 increases, thereby increasing the visibility of the viewer 4 and making it easier for the viewer 4 to recognize the avoidance display 50. Therefore, the HUD 10 can improve the ability to communicate information regarding urgency.

[0041] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims.

[0042] For example, in the avoidance display control process of Fig. 3, whether to apply a variable display speed or a constant display speed to the display speed of the avoidance display 50 is determined depending on whether or not the vehicle is traveling on a highway. However, regardless of whether or not the vehicle is traveling on a highway (or whether or not the traveling speed is greater than a predetermined speed), a constant display speed may be applied so that the display speed of the avoidance display 50 increases simply as the traveling speed of the vehicle 1 increases (for example, when the traveling speed is greater than a predetermined speed).

[0043] When the vehicle 1 is traveling at high speed, such as when traveling on a highway, the time until the vehicle approaches the obstacle 8 is short, and it is considered that the urgency of communicating obstacle avoidance is high. For this reason, the constant display speed may be determined so that the rate of increase in the display speed according to the traveling speed is greater when the vehicle 1 is traveling on a highway (when the traveling speed is higher than a predetermined speed) than when the vehicle 1 is traveling on an ordinary road (when the traveling speed is equal to or lower than the predetermined speed).

[0044] For example, if the traveling speed of vehicle 1 is 80 km / h, the displayed speed is 38 m / s, if the traveling speed of vehicle 1 is 100 km / h, the displayed speed is 44 m / s, and if the traveling speed of vehicle 1 is 120 km / h, the displayed speed is 50 m / s.The displayed speeds are determined so that the rate of increase in the displayed speed relative to an increase in vehicle speed is greater than the constant displayed speed applied when traveling on a public road.

[0045] The first speed V1 of the variable display speed may be faster than the constant display speed that is applied when the vehicle 1 is traveling at the same traveling speed.

[0046] In addition, in order to improve the visibility when the vehicle 1 is traveling at high speed, the color or size of the avoidance display 50 may be different when the traveling speed of the vehicle 1 is below a predetermined speed and when it is above the predetermined speed.

[0047] For example, when the traveling speed of the vehicle 1 is higher than a predetermined speed, the avoidance display 50 may be larger in size as shown in Fig. 9 than the avoidance display 50 shown in Fig. 2, thereby improving the visibility. Furthermore, when the traveling speed of the vehicle 1 is equal to or lower than a predetermined speed, the avoidance display 50 may be an image consisting of four arrow-shaped figures as shown in Fig. 10, and when the traveling speed is higher than the predetermined speed, the avoidance display 50 may be an image consisting of eight arrow-shaped figures as shown in Fig. 2, thereby improving the visibility by increasing the number of figures. Furthermore, when the traveling speed of the vehicle 1 is equal to or lower than the predetermined speed, the avoidance display 50 may be displayed in blue (a color that gives the impression of low urgency), and when the traveling speed is higher than the predetermined speed, the avoidance display 50 may be displayed in amber (a color that gives the impression of high urgency), thereby improving the visibility.

[0048] Although the above description uses an example in which the avoidance display 50 is made up of multiple arrow-shaped figures, it may instead be a single continuous arrow-shaped figure that indicates the avoidance route in a dynamic display extending from the front to the back, as shown in Fig. 11. In this case, the display speed of the avoidance display 50 is the speed at which the arrow-shaped figure extends. [Explanation of symbols]

[0049] 1 vehicle 3 Windshield 4. Viewer 7 Road surface 8 Obstacles 10 Head-Up Display (HUD) 11 Display 12 plane mirror 13 concave mirror 15 Case 20 Display area 30 Control Unit 31 Display control unit 32 Image generation unit 33 Storage section 41 Obstacle Sensor 42 GPS 43 Vehicle ECU 45 CAN bus 50 Evasion display 50a tip 50b end L display light P0 point P1 First point P2 Second point P3 Third point V1 first speed V2 2nd speed VI Virtual Image

Claims

1. a display that displays an image relating to a virtual image superimposed on an actual scene including a road surface on which a vehicle is traveling; an image generating unit that generates an avoidance display that is displayed on the display device to prompt the driver to avoid an obstacle on the road surface, the avoidance display being a dynamic display that moves or extends from the front to the back in the traveling direction of the vehicle and indicates an avoidance route; a display control unit that causes the image generation unit to generate the avoidance display so that the display speed, which is the speed at which the avoidance display moves or extends, becomes faster as the vehicle's traveling speed becomes faster.

2. 2. The head-up display according to claim 1, wherein the display control unit determines the display speed such that an increase rate of the display speed according to the traveling speed is greater when the vehicle is traveling on a highway than when the vehicle is traveling on an ordinary road.

3. 2. The head-up display according to claim 1, wherein the display control unit determines the display speed such that an increase rate of the display speed according to the traveling speed is greater when the traveling speed is greater than a predetermined speed than when the traveling speed is equal to or less than the predetermined speed.

4. The head-up display according to claim 1 , wherein the display control unit changes the color or size of the avoidance display depending on whether the traveling speed is equal to or lower than a predetermined speed or higher than the predetermined speed.

5. the avoidance display is an image in which a plurality of figures are connected from the front to the back in the traveling direction of the vehicle, The head-up display according to claim 1 , wherein the display control unit changes the number of the graphics when the traveling speed is equal to or lower than a predetermined speed and when the traveling speed is higher than the predetermined speed.

6. The head-up display according to claim 1 , wherein the display control unit increases the display speed when the leading edge of the avoidance display in the traveling direction is on the near side compared to when the leading edge is on the far side.

7. the avoidance display is displayed via a first point, a second point located further back than the first point, and a third point located further back than the second point, The display control unit displaying the avoidance indication at a first speed until the leading edge reaches the first point; displaying the avoidance display at a second speed slower than the first speed until the tip reaches the third point from the second point; The head-up display according to claim 6, wherein the avoidance display is displayed while the speed of the leading edge is reduced from the first speed to the second speed until the leading edge travels from the first point to the second point.

Images