Head-up display and its control device

Abstract

To provide a head-up display which allows a driver to intuitively recognize a distance feeling to an intersection to turn.SOLUTION: A head-up display 100 comprises: a display unit 20 which outputs display light for rendering an image; and a control unit 25 which controls the display unit 20. The head-up display projects the display light to a windshield 201 of a vehicle 200, through which actual scenery can be viewed, to display a virtual image of the display light so as to be superimposed on the actual scenery. The control unit 25 causes the display unit 20 to display a guidance image 50 showing a travel route. The guidance image 50 includes: a route image 51 which is rendered in perspective and shows a travel route; an intersection image 52 which is rendered in perspective and shows an intersection 301 to turn; and a turn direction image 53 which is rendered upright and planarly and shows a turn direction at the intersection 301. The control unit 25 changes modes of the route image 51, the intersection image 52 and the turn direction image 53 according to a distance to the intersection 301 from the vehicle 200.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a head-up display and its control device.

Background Art

[0002] The head-up display of Patent Document 1 displays first and second navigation guidance images. The first navigation guidance image guides a right turn at an intersection, while the second navigation guidance image is superimposed on the road surface as an augmented reality element to guide straight-ahead driving to the intersection.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the head-up display of Patent Document 1 has room for improvement in intuitively making the driver recognize the distance to the intersection where a turn should be made.

[0005] Therefore, an object of the present disclosure is to provide a head-up display and its control device that can intuitively make the driver recognize the distance to the intersection where a turn should be made.

Means for Solving the Problems

[0006] In one aspect, the following solution means are provided. A display unit that outputs display light representing an image, A control unit that controls the display unit, and is provided with, A head-up display that projects the display light onto a translucent screen of a vehicle where a real scene is visible, and superimposes and displays a virtual image of the display light on the real scene. The control unit causes the display unit to display a guidance image showing the travel route. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, The control unit changes the appearance of the route image, the intersection image, and the turn direction image according to the distance from the vehicle to the intersection.

[0007] Furthermore, in other respects, the following solutions are provided. A control device for a head-up display that projects display light onto a translucent screen of a vehicle that allows the actual scenery to be seen, thereby superimposing a virtual image of the display light onto the actual scenery, A guidance image showing the driving route is displayed on the head-up display. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, The appearance of the route image, the intersection image, and the turn direction image is changed according to the distance from the vehicle to the intersection. [Effects of the Invention]

[0008] This disclosure makes it possible to provide a head-up display and its control device that allow the driver to intuitively recognize the distance to the intersection where they should turn. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of a vehicle according to an embodiment of the present disclosure. [Figure 2]It is a schematic diagram of a head-up display according to an embodiment of the present disclosure. [Figure 3] It is a perspective view of a prism and a display according to an embodiment of the present disclosure. [Figure 4] It is a longitudinal sectional view of a prism and a display according to an embodiment of the present disclosure. [Figure 5] It is a diagram showing a virtual image overlapping with the actual scenery according to an embodiment of the present disclosure. [Figure 6] It is a diagram showing the transition of a guidance image (left turn) according to the first embodiment of the present disclosure. [Figure 7] It is a diagram showing a modified example of the first embodiment of the present disclosure, and is a diagram showing the transition of a guidance image (right turn) and the actual scenery. [Figure 8] It is a diagram showing the transition of a guidance image (left turn after branching) according to the second embodiment of the present disclosure. [Figure 9] It is a diagram showing a modified example of the second embodiment of the present disclosure, and is a diagram showing the transition of a guidance image (left turn after lane change). [Figure 10] It is a diagram showing the transition of a guidance image (warning of oncoming vehicles and pedestrians during a right turn) according to the third embodiment of the present disclosure. [Figure 11] It is a diagram showing a first modified example of the third embodiment of the present disclosure, and is a diagram showing the transition of a guidance image (warning of a red signal during a left turn). [Figure 12] It is a diagram showing a second modified example of the third embodiment of the present disclosure, and is a diagram showing the transition of a guidance image (warning of a stop sign during a right turn). [Figure 13] It is a diagram showing the transition of a guidance image (left turn immediately after a right turn) according to the fourth embodiment of the present disclosure.

Mode for Carrying Out the Invention

[0010] Hereinafter, each embodiment will be described in detail with reference to the accompanying drawings.

[0011] [Head-Up Display] As shown in Figure 1, the head-up display 100 is mounted on the dashboard of the vehicle 200. The head-up display 100 displays multiple virtual images V1 and V2 containing vehicle information by projecting display light L onto a windshield 201, which is an example of a projection target. When the viewer's viewpoint EP is within the visible area R, the viewer 1 can see the virtual images V1 and V2. Virtual image V1 is displayed within the virtual image display virtual area K1. Virtual image V2 is displayed within the virtual image display virtual area K2. The multiple virtual image display virtual areas K1 and K2 are each formed by an intangible plane and are tilted in different directions from each other.

[0012] As shown in Figure 2, the virtual image display area K1 extends along the height direction. Here, "along the height direction" means that the virtual image display area K1 is less than ±45° with respect to the height direction. The virtual image display area K2 is inclined relative to the virtual image display area K1. For example, the virtual image display area K2 follows the road surface. Here, "following the road surface" means that the virtual image display area K2 is less than ±45° with respect to the horizontal direction. In this example, the virtual image display area K2 is inclined upward as it moves away from the viewer 1.

[0013] As shown in Figure 5, the virtual image V2 is displayed along the road surface, which is the actual scenery as seen by the viewer 1. The virtual image V1 is displayed as if it is erected on the road surface, which is the actual scenery as seen by the viewer 1. The virtual image V2 contains information associated with the road surface, such as symbolic information such as route guidance arrows. The virtual image V1 contains textual information or sign information such as vehicle speed. Text includes numbers, alphabets, hiragana, katakana, kanji, etc.

[0014] Next, we will describe the configuration of the head-up display 100. As shown in Figure 2, the head-up display 100 comprises a concave mirror 12 which is an optical relay, a display unit 20 (an example of a display unit), a control unit 25 (an example of a display device), a case 30, and a prism 40.

[0015] The case 30 is formed in a box shape from a light-shielding resin or metal. Inside the case 30 are a concave mirror 12, a display unit 20, and a prism 40. The case 30 is provided with a window portion 31 made of a light-transmitting material that transmits the display light L generated in the internal space of the case 30 toward the windshield 201.

[0016] The display unit 20 has a display surface 21 that emits display light L representing an image. The display unit 20 may be of a type that has a liquid crystal panel and a lighting device, or it may be of a type that has a reflective display element such as a DMD (Digital Micro Mirror Device) element and a projector. The display surface 21 faces the front and lower side of the vehicle 200. The image displayed on the display surface 21 is subjected to distortion correction to correct the distortion of the virtual images V1 and V2 seen by the viewer 1. The display surface 21 is inclined with respect to the optical axis center La of the display light L. The optical axis center La is located at the center of the cross-section of the display light L.

[0017] As shown in Figure 4, the display surface 21 includes a first region 20a that emits display light L corresponding to a virtual image V1, and a second region 20b that emits display light L corresponding to a virtual image V2. Character information is displayed in the first region 20a, and symbolic information is displayed in the second region 20b.

[0018] As shown in Figure 2, the control unit 25 includes a CPU (Central Processing Unit), a GDC (Graphics Display Controller), a ROM (Read Only Memory), and a RAM (Random Access Memory). The control unit 25 acquires information such as vehicle speed and route guidance from an external source and generates an image to be displayed on the display surface 21 based on this information. The prism 40 is installed on the display surface 21, and the display light L emitted from the display surface 21 passes through it. The prism 40 will be described in detail later.

[0019] As shown in Figure 2, the concave mirror 12 has a reflective surface 12a that curves concavely along the height and width directions of the vehicle 200. The concave mirror 12 reflects the display light L transmitted through the prism 40 toward the windshield 201. The concave mirror 12 reflects toward the windshield 201 in a way that amplifies the display light L from the display surface 21. The reflective surface 12a of the concave mirror 12 faces the rear upper side of the vehicle 200. The concave mirror 12 has the function of suppressing distortion of the virtual image caused by reflection at the windshield 201.

[0020] Next, I will explain the configuration of the prism 40. As shown in Figures 3 and 4, the prism 40 is made of a material whose refractive index n is greater than that of air (n=1), such as glass or optical resin. The prism 40 is formed in a roughly plate-like shape that covers the display surface 21.

[0021] The prism 40 and the display unit 20 are rectangular plates that are long in the height direction. The prism 40 is positioned opposite the display surface 21 and includes an incident surface 41i into which display light from the display surface 21 is incident, and an exit surface 41o into which the display light L incident on the prism 40 via the incident surface 41i is emitted. The exit surface 41o includes a first top surface 42 that is parallel to the display surface 21 and an inclined surface 43 that is inclined with respect to the first top surface 42. The first top surface 42 and the inclined surface 43 are continuous in the height direction. The first top surface 42 is located above the inclined surface 43. The inclined surface 43 is inclined so that it approaches the display unit 20 as it goes downwards. The display unit 20 and the prism 40 may also be rectangular plates that are long in the width direction.

[0022] As shown in Figure 4, the virtual display plane 48A is located between the first top surface 42 and the incident surface 41i. The virtual display plane 48B is located between the inclined surface 43 and the incident surface 41i and extends in a direction that, for example, bisects the angle α made between the inclined surface 43 and the incident surface 41i. The optical axis center La of the display light L passes through the boundary between the virtual display plane 48A and the virtual display plane 48B. However, the optical axis center La of the display light L may pass through both the virtual display plane 48A and the virtual display plane 48B without passing through the boundary.

[0023] The angle θ1 of the extension of the virtual display plane 48A with respect to the optical axis center La (shown by the dashed line in Figure 4) is smaller than the angle θ2 of the virtual display plane 48B with respect to the optical axis center La. As the angle θ2 (see Figure 4) increases, the inclination angle of the virtual image display area K2 with respect to the height increases.

[0024] As shown in Figures 2 and 4, the virtual display plane 48A corresponds to the virtual image display virtual region K1 along the height direction. The virtual display plane 48B corresponds to the virtual image display virtual region K2 which is inclined relative to the virtual image display virtual region K1. The upper end of the virtual display plane 48A corresponds to the lower end of the virtual image display virtual region K1, and the lower end of the virtual display plane 48B corresponds to the upper end of the virtual image display virtual region K2. That is, the images of the virtual display planes 48A and 48B are inverted in the height direction and the vehicle front-rear direction and displayed as virtual images V1 and V2. As shown in Figures 2 and 5, the virtual image display virtual region K2 is located above the virtual image display virtual region K1 as viewed from the viewer 1. The upper end of the virtual image display virtual region K1 is in contact with the lower end of the virtual image display virtual region K2. The virtual image display virtual region K2 is inclined upward as it moves away from the viewer 1.

[0025] With the head-up display 100 configured as described above, when display light L is emitted from the display surface 21, the display light L enters the prism 40. The prism 40 acts in the same way as when the display light L is emitted from virtual display planes 48A and 48B that are oriented in different directions. After passing through the prism 40, the display light L is reflected by the concave mirror 12 toward the windshield 201. The display light L reflects off the windshield 201 and reaches the viewer 1. As a result, multiple virtual images V1 and V2 are displayed in different directions, corresponding to the orientations of the virtual display planes 48A and 48B.

[0026] Furthermore, the virtual image V2 in the virtual image display area K2 is tilted upward as it moves away from the viewer 1, so route guidance images and the like can be represented using perspective drawing that follows the road surface. In the embodiments described below, a virtual image display area K2 is used to display a guidance image, including perspective rendering, as described later. However, the representation of perspective rendering may be achieved by tilting the entire display surface of the display unit 20, or it may be achieved solely through software image processing, without hardware dependence.

[0027] [Display guidance image] Next, the display of guidance images by the head-up display 100 will be explained with reference to Figures 6 to 13.

[0028] The control unit 25 is equipped with guidance image display means as a functional configuration realized through the cooperation of hardware and software. The guidance image display means causes the display unit 20 to display a guidance image 50 showing the driving route. The control unit 25 acquires information about this driving route from an external navigation system (not shown). As shown in Figure 6, the guidance image 50 includes a route image 51, an intersection image 52, and a turn direction image 53. The route image 51 is represented using perspective drawing and shows the driving route (appropriate route) to be taken in order to reach a preset destination. The route image 51 is composed of a strip-shaped image that follows the road surface of the actual scenery, with a wider width on the near side (bottom) and a narrower width towards the far side (top). The intersection image 52 is represented using perspective drawing and shows the intersection 301 to be turned. The intersection image 52 is composed of an image showing the two near corners of the four corners of the intersection 301, for example, if the intersection 301 is a crossroads. Intersection 301 is not limited to a crossroads; it may be any type of intersection, such as a T-junction or a Y-junction. The turn direction image 53 is represented upright and planar, indicating the turn direction at intersection 301. The turn direction image 53 is composed of multiple arrow images arranged in a series in the turn direction, for example. It is desirable that the route image 51 and the turn direction image 53 use display colors that can emphasize that the route is safe (e.g., blue, green). It is also desirable that the intersection image 52 use a color with lower saturation and brightness compared to the image showing the appropriate route (e.g., an achromatic color such as gray).

[0029] The control unit 25 changes the appearance of the route image 51, intersection image 52, and turn direction image 53 of the guidance image 50 according to the distance from the vehicle 200 to the intersection 301. This allows the viewer 1 (driver) to intuitively recognize the distance to the intersection 301 where they should turn. Various embodiments of such guidance image 50 will be described below.

[0030] In Figures 6 to 13, reference numeral 302 indicates the center line, reference numeral 303 indicates the lane boundary line, reference numeral 304 indicates the stop line, reference numeral 305 indicates the pedestrian crossing, and reference numeral 306 indicates the branching point. Furthermore, the control unit 25 is equipped with a location information acquisition means, a route information acquisition means, an oncoming vehicle detection means, a pedestrian detection means, a signal information acquisition means, a stop information acquisition means, and the like, as functional configurations for realizing various embodiments.

[0031] (First embodiment) Figure 6 shows the transition of the guidance image (left turn) according to the first embodiment of this disclosure. As shown in Figure 6, when the control unit 25 displays a guidance image 50 to guide the vehicle to turn left at intersection 301, it transitions the guidance image 50 from (A1) to (A5) according to the distance from the vehicle 200 to intersection 301.

[0032] The control unit 25 displays the guidance image 50(A1) when the distance from the vehicle 200 to the intersection 301 where it will turn left is between a first threshold (e.g., 150m) and a second threshold (e.g., 50m). In the guidance image 50(A1), the control unit 25 enlarges the intersection image 52 and the turn direction image 53 as the distance from the vehicle 200 to the intersection 301 decreases. At this time, the control unit 25 does not change the size of the route image 51. With such a guidance image 50(A1), the viewer 1 can intuitively recognize that the intersection 301 where they should turn left is approaching, based on the enlargement of the intersection image 52 and the turn direction image 53. Also, in the guidance image 50(A1), since the size of the route image 51 does not change, the viewer 1 can intuitively recognize that the intersection 301 where they should turn left is approaching (e.g., less than 150m) while also recognizing that they are not immediately before the intersection 301 (e.g., more than 50m).

[0033] The control unit 25 displays guidance images 50(A2) and 50(A3) when the distance from the vehicle 200 to the intersection 301 where the vehicle will turn left is less than the second threshold. In guidance images 50(A2) and 50(A3), the control unit 25 enlarges the route image 51, intersection image 52, and turn direction image 53 as the distance from the vehicle 200 to the intersection 301 where the vehicle will turn left approaches. With such guidance images 50(A2) and 50(A3), the viewer 1 can intuitively recognize that the intersection 301 where the vehicle should turn left is approaching, based on the enlargement of the intersection image 52 and turn direction image 53. In addition, in guidance images 50(A2) and 50(A3), the route image 51 also enlarges according to the distance to the intersection 301 where the vehicle should turn left, so the viewer 1 can intuitively recognize that they are just before the intersection 301 where the vehicle should turn left (for example, they can recognize that it is less than 50m away).

[0034] The control unit 25 displays guidance images 50(A4) and 50(A5) when the vehicle 200 enters the intersection 301 where it should turn left. In guidance images 50(A4) and 50(A5), the intersection image 52 is hidden, allowing the viewer 1 to intuitively recognize that the vehicle 200 has entered the intersection 301 where it should turn left. In addition, in guidance images 50(A4) and 50(A5), the control unit 25 rotates the route image 51 to show that it is moving in the direction of travel, and slides the turn direction image 53 out from the guidance image 50 in the opposite direction of travel according to the progress of the turn. This allows the viewer 1 to intuitively recognize the progress of the turn at the intersection 301 where it should turn left.

[0035] Figure 7 is a diagram showing a modified example of the first embodiment of the present disclosure, and is a diagram showing the transition between a guidance image (right turn) and the actual scenery. As shown in Figure 7, when the control unit 25 displays a guidance image 50 to guide the vehicle to turn right at intersection 301, it transitions the guidance image 50 from (B1) to (B4) according to the distance from the vehicle 200 to intersection 301 where the vehicle will turn right.

[0036] The control unit 25 displays the guidance image 50(B1) when the distance from the vehicle 200 to the intersection 301 where the vehicle turns right is between the first and second thresholds. In the guidance image 50(B1), the control unit 25 enlarges the intersection image 52 and the turn direction image 53 as the distance from the vehicle 200 to the intersection 301 decreases. In the guidance image 50(B1), the control unit 25 does not change the size of the route image 51.

[0037] The control unit 25 displays guidance images 50(B2) and 50(B3) when the distance from the vehicle 200 to the intersection 301 where the vehicle will turn right is less than the second threshold. In the guidance images 50(B2) and 50(B3), the control unit 25 enlarges the route image 51, the intersection image 52, and the turn direction image 53 as the distance from the vehicle 200 to the intersection 301 where the vehicle will turn right decreases.

[0038] The control unit 25 displays the guidance image 50(B4) when the vehicle 200 enters the intersection 301 where it should turn right. In the guidance image 50(B4), the control unit 25 hides the intersection image 52. In the guidance image 50(B4), the control unit 25 rotates the route image 51 to show it moving in the direction of travel, and slides the turn direction image 53 out of the guidance image 50 in the opposite direction of travel according to the progress of the turn.

[0039] (Second example) Figure 8 shows the transition of the guidance image (turn left after branching) according to the second embodiment of this disclosure. As shown in Figure 8, when branching is required before a turn at intersection 301, the control unit 25 transitions the guidance images 50 from (C1) to (C5) according to the distance from the vehicle 200 to the branching point 306 or intersection 301.

[0040] The control unit 25 displays a guidance image 50(C1) when the distance from the vehicle 200 to the branching point 306 is between the third threshold (e.g., 150m) and the fourth threshold (e.g., 50m). In the guidance image 50(C1), the control unit 25 displays an image 54 of the currently traveled unsuitable route. The unsuitable route image 54 indicates an inappropriate route that deviates from the proper route. It is also desirable that the unsuitable route image 54 be a color with lower saturation and brightness than the image showing the proper route (e.g., achromatic color such as gray). In addition, in the guidance image 50(C1), the control unit 25 may also display a lane image 55 indicating the presence of the branching point 306. If the lane image 55 is displayed, it is also desirable that the lane image 55 be a color with lower saturation and brightness than the image showing the proper route (e.g., achromatic color such as gray).

[0041] The control unit 25 displays guidance images 50(C2) and 50(C3) when the distance from the vehicle 200 to the branching point 306 is less than the fourth threshold. In the guidance images 50(C2) and 50(C3), the control unit 25 displays an unsuitable route image 54, a lane image 55, and a pre-route image 56 that shows the appropriate route leading to the route image 51 that guides the vehicle to turn left. This pre-route image 56 is displayed in a color that can emphasize that it is a safe route (for example, blue or green), and it is desirable that it be the same color as the route image 51. With such guidance images 50(C2) and 50(C3), the viewer 1 can intuitively recognize that a branching from the unsuitable route to the appropriate route is necessary before turning left at intersection 301.

[0042] The control unit 25 displays the guidance image 50(C4) when the vehicle 200 enters the branching area of ​​the branching point 306. At this time, the control unit 25 hides the unsuitable route image 54 and the lane image 55. Since the unsuitable route image 54 and the lane image 55 are hidden in the guidance image 50(C4), the observer 1 can intuitively recognize that the vehicle 200 has entered the area where it should branch.

[0043] The control unit 25 displays guidance image 50(C5) after the branching is complete. Guidance image 50(C5) corresponds to guidance image 50(A1) in Figure 6, and from here, in order to provide guidance for turning left at intersection 301, the control unit 25 transitions through guidance images 50(A1) to 50(A5) as shown in Figure 6.

[0044] Figure 9 is a diagram showing a modified example of the second embodiment of the present disclosure, and is a diagram showing the transition of the guidance image (turning left after changing lanes). As shown in Figure 9, when a lane change is required before turning at intersection 301, the control unit 25 transitions the guidance images 50 from (D1) to (D5).

[0045] Guidance image 50 (D1) shows the lane the vehicle is currently traveling in (unsuitable route) and the lane it should change to (suitable route) using lane image 55.

[0046] The control unit 25 displays a guidance image 50(D2) which includes a lane image 55 and a pre-route image 56 that shows the appropriate route leading to a left-turn guidance route image 51. With such a guidance image 50(D2), the viewer 1 can intuitively recognize that a lane change from an unsuitable route to a suitable route is necessary before turning left at intersection 301.

[0047] When the vehicle 200 begins to change lanes, the control unit 25 displays the guidance image 50(D3). At this time, the control unit 25 hides the lane image 55. Since the lane image 55 is not displayed in the guidance image 50(D3), the observer 1 can intuitively recognize that the vehicle 200 has entered the correct lane.

[0048] After the line change is complete, the control unit 25 displays guidance images 50(D4) and 50(D5). Guidance image 50(D5) corresponds to guidance image 50(A1) in Figure 6, and from here, in order to provide left-turn guidance at intersection 301, the control unit 25 transitions through guidance images 50(A1) to 50(A5) as shown in Figure 6.

[0049] (Third embodiment) Figure 10 shows the transition of guidance images (warnings for oncoming vehicles and pedestrians when turning right) according to the third embodiment of this disclosure. If the control unit 25 detects a factor that would cause disadvantage to the vehicle 200 continuing to move while the guidance image 50 is being displayed, it will display a warning image within the guidance image 50. Factors that cause disadvantage include, for example, oncoming vehicles, pedestrians, and other obstacles that have entered the driving path. Factors that cause disadvantage may also include signs indicating that it will be a violation of the law if the vehicle continues along the driving path without performing a prescribed driving action such as coming to a stop. These factors that cause disadvantage are detected by sensors (not shown) such as millimeter-wave radar sensors and imaging sensors for sign recognition. For example, as shown in Figure 10, if the control unit 25 detects an oncoming vehicle or pedestrian while giving right-turn guidance, it will transition the guidance image 50 as shown in (E1) to (E6). Note that guidance images 50(E1), 50(E2), and 50(E3) correspond to guidance images 50(B1), 50(B2), and 50(B3) in Figure 7, so their explanation is omitted.

[0050] When the vehicle 200 enters the intersection 301 where it should turn right, the control unit 25 normally displays a guidance image 50(B4) including a route image 51 and a turn direction image 53, as shown in Figure 7. On the other hand, if the control unit 25 detects an oncoming vehicle approaching the right-turn path, it displays a guidance image 50(E4) including a warning object 61A and a warning type icon 62A. Furthermore, if the control unit 25 detects a pedestrian crossing the crosswalk 305 on the right-turn path, it displays a guidance image 50(E5) including a warning object 61B and a warning type icon 62B. With these guidance images 50(E4) and 50(E5), the viewer 1 can intuitively recognize the possibility of collision with an oncoming vehicle or pedestrian that would cause harm if the vehicle 200 continues to proceed. In addition, since the control unit 25 hides the turn direction image 53 in the guidance images 50(E4) and 50(E5), the viewer 1 can intuitively recognize that it should not proceed.

[0051] The warning objects 61A and 61B should traverse the path image 51 and preferably be displayed in a color that can emphasize the warning (e.g., red, amber, yellow). Furthermore, the path image 51 traversed by the warning objects 61A and 61B should preferably be displayed in a color that can emphasize that it is a safe path (e.g., blue, green), as mentioned above. With such warning objects 61A and 61B, the viewer 1 can more strongly recognize that they should not proceed.

[0052] The warning type icons 62A and 62B should preferably be images that mimic oncoming vehicles or pedestrians, and should be displayed in colors that can emphasize the warning (e.g., red, amber, yellow). With such warning type icons 62A and 62B, the viewer 1 can recognize the factors that would cause harm by proceeding, and more strongly understand that they should not proceed.

[0053] If no oncoming vehicles or pedestrians are detected, the control unit 25 displays the normal guidance image 50 (E6) and resumes the right-turn guidance.

[0054] Figure 11 is a diagram showing a first modified example of the third embodiment of the present disclosure, and is a diagram showing the transition of the guidance image (warning of a red light when turning left). As shown in Figure 11, the control unit 25 can transition the guidance image 50 from (F1) to (F4) according to the lighting status of the traffic lights in the direction of travel at the intersection 301 where the turn is to be made.

[0055] The control unit 25 displays the guidance image 50(F1) when the distance from the vehicle 200 to the intersection 301 where the vehicle will turn left is between the first and second thresholds. In the guidance image 50(F1), the control unit 25 enlarges the intersection image 52 and the turn direction image 53 as the distance from the vehicle 200 to the intersection 301 where the vehicle will turn left decreases. The guidance image 50(F1) also includes a preliminary warning icon 63A indicating that there is a traffic light at the intersection 301 where the vehicle will turn left. The preliminary warning icon 63A may indicate a traffic light in a fully illuminated state (red, yellow, and blue lights all on) or may indicate the current illumination state of the traffic light.

[0056] The control unit 25 displays guidance images 50(F2) and 50(F3) when the distance from the vehicle 200 to the intersection 301 where it will turn left is less than the second threshold. In guidance images 50(F2) and 50(F3), the control unit 25 enlarges the route image 51, intersection image 52, and turn direction image 53 as the distance from the vehicle 200 to the intersection 301 where it will turn left decreases. Guidance image 50(F2) also includes a preliminary warning icon 63A that indicates the current illumination status of the traffic lights. With such guidance image 50(F2), it is possible to recognize in advance the illumination status of the traffic lights in the direction of travel at the intersection 301 where it will turn left.

[0057] The control unit 25 displays a warning object 61C and a warning type icon 62C in the guidance image 50(F3) when the traffic light in the direction of travel at the intersection 301 where the vehicle is turning left is illuminated red. With such a guidance image 50(F3), the viewer 1 can intuitively recognize the possibility of running a red light, which would result in disadvantages if the vehicle 200 continues to proceed. In addition, the control unit 25 hides the turn direction image 53 in the guidance image 50(F3), so the viewer 1 can intuitively recognize that they should not proceed.

[0058] The warning object 61C should ideally traverse the route image 51 and be displayed in a color that can emphasize the warning (e.g., red, amber, or yellow). Furthermore, the warning type icon 62C should ideally be an image resembling a traffic light with a red light illuminated. Such warning objects 61C and warning type icons 62C allow the viewer 1 to recognize the factors that would cause harm by proceeding and to more strongly understand that they should not proceed.

[0059] When the traffic light switches to a green state, the control unit 25 displays the normal guidance image 50 (F4) and resumes the left-turn guidance.

[0060] Figure 12 is a diagram showing a second modified example of the third embodiment of the present disclosure, and is a diagram showing the transition of the guidance image (warning to stop when turning right). As shown in Figure 12, the control unit 25 can transition the guidance images 50 as shown in (G1) to (G4) when the intersection 301 to be turned at requests a stop.

[0061] The control unit 25 displays the guidance image 50(G1) when the distance from the vehicle 200 to the intersection 301 where the vehicle will turn right is between the first and second thresholds. In the guidance image 50(G1), the control unit 25 enlarges the intersection image 52 and the turn direction image 53 as the distance from the vehicle 200 to the intersection 301 where the vehicle will turn right decreases. The guidance image 50(G1) also includes a preliminary warning icon 63B indicating that there is a sign requiring a stop at the intersection 301 where the vehicle will turn right.

[0062] The control unit 25 displays guidance images 50(G2) and 50(G3) when the distance from vehicle 200 to intersection 301 where it will turn right is less than the second threshold. In guidance images 50(G2) and 50(G3), the control unit 25 enlarges the route image 51 and intersection image 52 as the distance from vehicle 200 to intersection 301 approaches. Guidance images 50(G2) and 50(G3) also include a warning object 61D and a warning type icon 62D that request a stop at the stop line 304. At this time, the control unit 25 hides the turn direction image 53. With such guidance images 50(G2) and 50(G3), the viewer 1 can intuitively recognize the possibility of ignoring a stop sign, which would result in disadvantages if vehicle 200 continues to proceed. Furthermore, the control unit 25 hides the turn direction image 53 in the guidance images 50(G2) and 50(G3), so that the viewer 1 can intuitively recognize that they should not proceed.

[0063] The warning object 61D should traverse the route image 51 and preferably be displayed in a color that can emphasize the warning (e.g., red, amber, yellow). Furthermore, the warning type icon 62D should preferably be an image resembling a stop sign. Such warning objects 61D and warning type icons 62D allow the viewer 1 to recognize the factors that would cause harm by proceeding and to more strongly understand that they must not proceed.

[0064] When the control unit 25 detects that the vehicle 200 has stopped, it displays the normal guidance image 50 (G4) and resumes the right-turn guidance.

[0065] (Fourth embodiment) Figure 13 shows the transition of guidance images (turning right and then immediately left) according to the fourth embodiment of this disclosure. As shown in Figure 13, if the control unit 25 immediately provides left turn guidance (left branch guidance) after providing right turn guidance, it can transition the guidance images 50 as shown in (H1) to (H5).

[0066] The control unit 25 displays the guidance image 50(H1) when the distance from the vehicle 200 to the intersection 301 where the vehicle will turn right is less than the second threshold. In the guidance image 50(H1), the control unit 25 enlarges the route image 51, intersection image 52, and turn direction image 53 as the distance from the vehicle 200 to the intersection 301 where the vehicle will turn right decreases. In addition, the guidance image 50(H1) shows the lane to proceed in after the right turn using the route image 51 and lane image 55, and also shows that the vehicle should turn left after the right turn using the route image 51 and turn direction image 53.

[0067] The control unit 25 displays guidance image 50(H2) when the vehicle 200 enters intersection 301 where it should turn right. In guidance image 50(H2), the control unit 25 hides the intersection image 52. In guidance image 50(H2), the lane to proceed in after the right turn is shown by route image 51 and lane image 55. In guidance image 50(H2), the control unit 25 rotates the route image 51 to show it moving in the direction of travel, and slides the turn direction image 53 out of the guidance image 50 in the opposite direction of travel according to the progress of the turn.

[0068] The control unit 25 displays a guidance image 50(H3) towards the end of the right turn. The guidance image 50(H3) includes a route image 51 showing the path to take when turning left after the right turn, and a turn direction image 53 showing the direction of the left turn.

[0069] The control unit 25 displays guidance images 50(H4) and (H5) after the vehicle turns right. In the guidance images 50(H4) and (H5), the control unit 25 enlarges the route image 51 and the turn direction image 53 as the distance from the vehicle 200 to the intersection 301 (junction 306) where the vehicle turns left decreases. With such guidance images 50(H1) to (H5), the viewer 1 can intuitively recognize that they should turn left immediately after turning right.

[0070] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above. [Explanation of Symbols]

[0071] 1. Sighted person 100 Head-Up Displays 20 Display 25 Control Unit 50 Guidance Images 51 Path Image 52 Intersection Images 53 Turn Direction Image 54 Unsuitable Path Images 55-lane image 56 Pre-route image 61A~61D Warning Objects 62A~62D Warning Type Icons 63A, 63B Pre-warning icon 200 vehicles 201 Windshield Intersection 301 302 Center Line 303 Lane boundary line 304 Stop line 305 Pedestrian crossing 306 Junction

Claims

1. A control device for a head-up display that projects display light onto a translucent screen of a vehicle that allows the actual scenery to be seen, thereby superimposing a virtual image of the display light onto the actual scenery, A guidance image showing the driving route is displayed on the head-up display. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, Depending on the distance from the vehicle to the intersection, the appearance of the route image, the intersection image, and the turn direction image are changed. When the distance from the vehicle to the intersection is between the first threshold and the second threshold (second threshold < first threshold), the intersection image and the turn direction image are enlarged as the distance from the vehicle to the intersection decreases. A control device for a head-up display, which, when the distance from the vehicle to the intersection is less than the second threshold, enlarges the route image, the intersection image, and the turn direction image as the distance from the vehicle to the intersection decreases.

2. The control device for a head-up display according to Claim 1, wherein when the vehicle enters the intersection, the guidance image is rotated and displayed so as to move in the direction of travel of the route image, and the turn direction image is slid out from the guidance image according to the degree of the turn.

3. A control device for a head-up display that projects display light onto a translucent screen of a vehicle on which the actual scenery can be seen, thereby superimposing a virtual image of the display light onto the actual scenery, A guidance image showing the driving route is displayed on the head-up display. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, Depending on the distance from the vehicle to the intersection, the appearance of the route image, the intersection image, and the turn direction image are changed. A control device for a head-up display that, when a lane change or branching is required before a turn at the aforementioned intersection, displays an image of the currently traveled unsuitable route or lane, and then displays a pre-route image indicating a suitable route that connects to the aforementioned route image.

4. A control device for a head-up display that projects display light onto a translucent screen of a vehicle on which the actual scenery can be seen, thereby superimposing a virtual image of the display light onto the actual scenery, A guidance image showing the driving route is displayed on the head-up display. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, Depending on the distance from the vehicle to the intersection, the appearance of the route image, the intersection image, and the turn direction image are changed. If, while the guidance image is being displayed, factors that would cause disadvantage to the vehicle continuing to move are detected, a warning image will be displayed within the guidance image. A control device for a head-up display that hides the turn direction image while the warning image is displayed.

5. A control device for a head-up display that projects display light onto a translucent screen of a vehicle on which the actual scenery can be seen, thereby superimposing a virtual image of the display light onto the actual scenery, A guidance image showing the driving route is displayed on the head-up display. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, Depending on the distance from the vehicle to the intersection, the appearance of the route image, the intersection image, and the turn direction image are changed. If, while the guidance image is being displayed, factors that would cause disadvantage to the vehicle continuing to move are detected, a warning image will be displayed within the guidance image. The warning image includes a warning object that traverses the path image, and is a control device for a head-up display.

6. A control device for a head-up display that projects display light onto a translucent screen of a vehicle on which the actual scenery can be seen, thereby superimposing a virtual image of the display light onto the actual scenery, A guidance image showing the driving route is displayed on the head-up display. The aforementioned guidance image is A route image representing the aforementioned travel route, expressed using perspective drawing, An image of an intersection showing a turn, expressed using perspective, Includes a turn direction image, which is represented upright and planar, and indicates the direction of the turn at the intersection, Depending on the distance from the vehicle to the intersection, the appearance of the route image, the intersection image, and the turn direction image are changed. If, while the guidance image is being displayed, factors that would cause disadvantage to the vehicle continuing to move are detected, a warning image will be displayed within the guidance image. The control device for a head-up display includes a warning image and a warning type icon indicating the type of the factor.

7. A head-up display comprising a control device for a head-up display according to any one of claims 1 to 6.

Images