JP7639814B2 - Head-up display device - Google Patents

Description

The present invention relates to a head-up display (HUD) device that displays virtual images, and more particularly to an HUD device having a light field type stereoscopic display unit (light field display) that can project (project) image display light onto a projection member such as a windshield or combiner of a vehicle (vehicle) and display multiple virtual images in front of the driver (viewer or user) at a desired virtual image display distance.

Patent document 1 discloses a technology that allows a HUD device using a light field display to display multiple annotations (information such as text, objections, signs, commands, etc. displayed by the display) at different focal lengths (see, for example, claims 1 and 2, paragraph [0012], Figures 3 to 6, etc.).

Patent No. 6580800

A ray of light in space can be represented by its position within a plane as it passes through it, with the optical axis as its normal, and the angle (in other words, its direction) that the ray makes with the optical axis.

Taking this into consideration, a light field type 3D display device (3D display unit) uses, for example, a combination of a high-definition flat display and small lenses (lens array) to control the "position of lit pixels" on the flat display and reproduce light rays specified at any position and direction.

In addition, the depth position (depth distance) of a three-dimensional image in light space (light field), for example as seen from the light field display side, can be adjusted as appropriate by changing the "lighting pattern of the lit pixels (lit picture elements)" on the flat display.

In this way, light rays can be reproduced at any position (position on a two-dimensional surface), direction and depth by controlling the lighting position and lighting pattern of pixels on a flat display.

The inventors have conducted various studies on generating light field data (data for displaying images that contain information on at least one of the lit pixels and lighting patterns on a flat display) by rendering, and as a result, the following problems have become apparent.

In the following explanation, it is assumed that a flat display has a large number of pixels (picture elements) arranged in a rectangular area when viewed in a planar view, and that the horizontal direction of the rectangle corresponds to the horizontal direction, which is the direction along the line segment connecting the left and right eyes of an observer (or a viewer who sees a stereoscopic image) who observes a stereoscopic image in real space. The vertical direction of the rectangle is the direction corresponding to the height of the observer (viewer) (referred to as the height direction). Additionally, the direction along the line segment (normal) perpendicular to the rectangle and away from the rectangle is referred to as the depth direction.

Now, suppose that two different stereoscopic images are displayed at different depth positions. When two stereoscopic images are displayed at the same depth position, by appropriately setting the horizontal distance (horizontal distance) between each stereoscopic image in space, it is possible to prevent horizontally adjacent pixels used to display each stereoscopic image from overlapping on a flat display (however, in cases where the stereoscopic images are placed very close to each other, pixel overlap may become a problem. This does not mean that the present invention does not encounter any problems in this regard).

On the other hand, when two 3D images are displayed at different depths, there is a high possibility that the pixels used to display each 3D image, which are arranged horizontally on the flat display, will overlap. This is for the following reasons:

An example will be given below (however, the present invention is not limited to this description). A light point constituting a stereoscopic image emits a pair of light rays for the left eye and the right eye. The angle (convergence angle) that the pair of light rays make when they intersect at the light point increases as the depth distance from the light field display (for example, the center position of the lens) to the stereoscopic image decreases. At this time, the greater the convergence angle, the greater the interval between the pixels on the flat display corresponding to each of the two light rays. Therefore, for example, when the depth distance of one stereoscopic image is changed during display, the convergence angle increases and the interval between the two pixels corresponding to the two light rays increases, resulting in at least one of the pixels for displaying one of the stereoscopic images entering the arrangement area of the pixels for displaying the other stereoscopic image, and in some cases, overlapping with one of the pixels for displaying the other stereoscopic image.

In other words, one pixel is used to display two stereoscopic images, resulting in pixel collision. In this case, it is unclear which stereoscopic image the pixel will be used to display, and proper light field rendering cannot be performed. In the worst case, this means that both stereoscopic images cannot be displayed properly. The above problems have been identified by the present inventor.

One of the objectives of the present invention is to avoid a situation in which proper light field rendering cannot be performed in a HUD device having a light field type stereoscopic display unit due to overlap between pixels for displaying one image and pixels for displaying another image.

Other objects of the present invention will become apparent to those skilled in the art by reference to the following exemplary aspects and best modes for carrying out the present invention and the accompanying drawings.

Below, examples of embodiments according to the present invention are provided to facilitate an understanding of the overview of the present invention.

In a first aspect, a head-up display device is a head-up display (HUD) device that displays a virtual image,
a light field type stereoscopic display unit including a display and an optical member and reproducing light rays of a stereoscopic image;
an optical system that projects the light beam reproduced by the stereoscopic display unit onto a projection target;
A control unit that controls display of an image on the display;
having
When the distance between the stereoscopic display unit and the stereoscopic image is defined as a depth distance, and the direction along the depth distance when the stereoscopic image is viewed from the stereoscopic display unit is defined as a depth direction,
The control unit is
setting a first display position including at least a position in a depth direction of a first image showing the first information, and a second display position including at least a position in a depth direction of a second image showing the second information;
determining whether or not a first pixel on the display used when displaying the first image at the first display position overlaps with a second pixel used when displaying the second image at the second display position, and/or whether there is a possibility of overlap;
If it is determined that the first pixel and the second pixel overlap or are likely to overlap,
The display of the image with the higher display priority is given priority, and overlap suppression control is implemented, including turning off or reducing the brightness of at least the pixels in the overlapping portion of the image with the lower display priority.

In the first aspect, when the display pixels of the first and second images overlap or are likely to overlap on the display, priority is given to lighting the display pixels of the image with a higher priority based on the display priority (priority order). By turning off the display pixels of the image with a lower priority (priority order) or reducing their brightness (in other words, implementing overlap suppression control), pixel overlap is avoided. This enables the generation of light field data by rendering.

When a portion of the display pixels of a first image overlaps (or there is a possibility of overlapping) with a portion of the display pixels of a second image, overlap suppression control may be performed only on the display pixels of the image with the lower priority in the overlapping portion, or overlap suppression control may be performed on the entire image with the lower priority.

In the former case, the portion of the lower priority image that is displayed using non-overlapping pixels is visible, and information can be presented to the viewer (observer) through that portion of the image. In the latter case, the entire lower priority image is made invisible or its visibility is reduced, allowing the viewer (observer) to focus their attention only on the (virtual image of) the higher priority image, and to efficiently obtain or sense information.

In a second aspect dependent on the first aspect,
The control unit is
When at least one of the first and second images is a dynamic image corresponding to a virtual image superimposed on a moving object, the possibility of overlap may be determined based on a prediction of the movement of the object.

According to the second aspect, for example, for an image superimposed on a moving object, the possibility of overlap of display pixels can be determined based on a prediction of the object's movement, and overlap avoidance control can be implemented.

For example, when a warning sign is superimposed on a person entering a road, the possibility of overlap with other signs can be determined based on the movement of the object, and the warning sign can be displayed with priority as appropriate. In this case, safety can be ensured by displaying warnings and other messages that are important for ensuring safety with priority.

In a third aspect dependent on the first or second aspect,
The control unit is
The overlap suppression control may be implemented by prioritizing the displays in descending order of priority as follows: warning display, navigation display, POI (Point of Interest) display, and other displays.

According to the third aspect, for example, it is possible to efficiently and quickly take the necessary measures to avoid duplication according to a predetermined priority list. By prioritizing information in the order of highest priority, such as warnings, navigation information, and POI information, it is possible to present information that is considered necessary (important) for driving to the user of the HUD device.

In a fourth aspect dependent on any one of the first to third aspects,
Further comprising a driving scene determination unit,
The control unit may variably control the priority of the display images in accordance with the driving scene.

According to the fourth aspect, by updating (changing) the display priority depending on the driving scene, it is possible to prioritize displays that are useful for the current driving scene, and practical information can be displayed while suppressing crosstalk.

In a fifth aspect dependent on any one of the first to fourth aspects,
Further comprising a visual detection unit,
The control unit is
After displaying one of the images in accordance with the priority order, if the visibility detection unit detects that the displayed image has been viewed by a viewer, at least a portion of the display restriction on the pixels of the other image that was restricted from display may be lifted.

According to the fifth aspect, after the highest priority image (virtual image) is viewed, at least a portion of the restrictions on images (virtual images) whose display has been restricted under specified conditions is lifted, thereby enabling the viewer to view useful displays of other images (virtual images).

In a sixth aspect dependent on any one of the first to fifth aspects,
The control unit is
When pixels for displaying the first image and pixels for displaying the second image do not overlap but are within a predetermined distance, or when it is determined that the distance between the pixels has become closer to within the predetermined distance due to movement of at least one of the pixels, the overlap suppression control may be performed on the pixels of the image with the lower priority.

According to the sixth aspect, if there are adjacent pixels within a predetermined distance among the display pixels of the first and second images, overlap suppression control (in other words, overlap avoidance processing) can be started for the display pixels of the image with the lower priority. A state in which images are close to each other can be said to be a state in which the images are difficult to distinguish (a state in which visibility is reduced) even if there is no overlap. In this state, a process to quickly resolve (suppress) the conflict between the images can be performed, thereby effectively suppressing the decrease in visibility.

In a seventh aspect dependent on any one of the first to sixth aspects,
The control unit is
When pixels for displaying the first image and pixels for displaying the second image do not overlap, but it is determined that the two pixels have come within a predetermined distance due to movement of at least one of them, and the distance between the two pixels becomes even smaller over time, a fade-out process may be implemented to gradually reduce the brightness of the pixels of the image with a lower priority.

According to the seventh aspect, by implementing fade-out control, the degree of visibility restriction is gradually increased, thereby making it possible to ease the visual change accompanying the visibility control. This makes it possible to reduce the sense of incongruity caused by the change in vision.

In an eighth aspect dependent on any one of the first to seventh aspects,
The control unit is
A notification image may be displayed to inform the user that a restriction is imposed on the display of an image with a low priority due to the overlap suppression control.

According to the eighth aspect, the viewer is notified that not all of the information is completely displayed, but that at least one piece of information is not displayed or is incompletely displayed. This allows the viewer to accurately grasp the current display situation.

In a ninth aspect dependent on the fourth aspect,
The driving scene determined by the driving scene determination unit is
A first scene of a city area on a sunny day (urban area or traffic volume above a certain value), or a highway on a sunny day (urban area), or a busy intersection, or a school route;
A second scene in a city on a clear day (in the countryside or with traffic volume below a certain level), or on a highway on a clear day (in the countryside), or when the driver is looking away or returning from looking away, or in a location or area where accidents frequently occur;
A third scene of a nighttime urban area (urban area or area with traffic volume above a certain value) or a nighttime highway (urban area);
A fourth scene of a nighttime urban area (rural area or traffic volume below a certain value) or a nighttime highway (rural area);
The fifth scene, during a traffic jam stop,
The sixth scene is when there are restrictions on vehicle movement (including no U-turns or construction work).
The seventh scene during autonomous driving,
at least four of
As indications to which priority is given,
Warning signs,
Navigation display,
POI display,
The traffic sign recognition (TSR) indications may include at least two of:

According to the ninth aspect, for example, the display priority of each of the four display contents (at least two of them) corresponding to seven driving scenes (at least four of them) can be determined in advance, for example in list format. This allows the priority of the display contents (display information) to be quickly updated according to each driving scene, and appropriate display control to be performed.

In a tenth aspect dependent on the ninth aspect,
The warning display is:
A first warning about high relative velocity objects (including oncoming vehicles and pedestrians);
A second warning for low relative velocity objects (including vehicles traveling in the same direction); and
A third warning regarding notifications regarding the situation around the vehicle (including notifications of natural disasters and traffic accidents);
Including,
The first warning is set to have a higher priority for display than the second and third warnings,
Regarding the second warning and the third warning, in the first to sixth scenes, the second warning is set to have a higher priority, but in the seventh scene, the second warning and the third warning may be set to have the same priority.

In the tenth aspect, the warning display is further divided into three types (first, second, and third warnings), and a priority is set for each type depending on the driving scene. The first warning has the highest priority, and in the first to sixth scenes, the second warning has a higher priority than the third warning, but in the seventh scene (when the vehicle is in autonomous driving), the second and third warnings are set to have the same priority, taking into account that the driver is not generally involved in driving.

According to this aspect, even when there are multiple warning displays and the display pixels of one warning display overlap with the display pixels of another warning display, the overlap of pixels can be suppressed according to the priority (priority order) that takes into account the driving scene set for each warning content (warning type). Since warnings can always be displayed appropriately, safety is improved.

Those skilled in the art will readily appreciate that the exemplified embodiments of the present invention may be further modified without departing from the spirit of the present invention.

1A and 1B are diagrams for explaining the principle of three-dimensional display using a light field method (light ray reproduction method). FIG. 2(A) is a diagram showing an example of the basic configuration of a light field type (light ray reproduction type) stereoscopic display unit (stereoscopic display device) and an example of displaying (generating) a stereoscopic image. FIG. 2(B) is a diagram showing an example of displaying a virtual image by light rays for the left eye and right eye emitted from a single light point that constitutes a stereoscopic image in a HUD device using a stereoscopic display unit (stereoscopic display device). FIG. 3A is a diagram for explaining the display of a stereoscopic image in a stereoscopic display section (stereoscopic display device) using a lenticular lens, and FIG. 3B is a perspective view of the stereoscopic display section (stereoscopic display device) using a lenticular lens. FIG. 4(A) is a diagram showing an example of the arrangement of display pixels on a flat display when two stereoscopic images are displayed at the same depth position (no overlap), and FIG. 4(B) is a diagram showing an example of the arrangement of display pixels on a flat display when two stereoscopic images are displayed at different depth positions (with overlap). 5A and 5B are diagrams showing examples of measures to be taken when display pixels overlap on a flat display when two stereoscopic images with different depth positions are displayed. FIG. 6(A) shows an example of overlapping display pixels when two stereoscopic images at different depth positions are displayed and one of the stereoscopic images is moved horizontally, and FIGS. 6(B) and (C) show examples of measures to avoid overlapping display pixels. FIG. 7(A) shows an example of overlap of display pixels when two stereoscopic images at different depth positions are displayed and one of the stereoscopic images is moved horizontally. FIG. 7(B) shows an example of a pre-emptive measure when overlap of display pixels is predicted. FIG. 7(C) and (D) show examples of measures for avoiding overlap of display pixels. FIG. 8 is a diagram showing an example of the configuration of a HUD device using a light field type (light ray reproduction type) stereoscopic display unit (stereoscopic display device), and an example of a virtual image display. FIG. 9(A) is a diagram showing an example of display priority (display priority order), FIGS. 9(B) and (C) are diagrams showing an example of suppressing overlap between virtual images displayed by the HUD device by implementing measures to avoid overlap of display pixels, and FIG. 9(D) is a diagram showing an example of display when control for suppressing overlap between virtual images is released. 10A and 10B are diagrams showing an example in which overlap between virtual images displayed by a HUD device is suppressed by implementing measures to avoid overlap of display pixels. 11A to 11C are diagrams showing an example in which overlap between virtual images displayed by a HUD device is suppressed by implementing measures to avoid overlap of display pixels. FIG. 12A is a diagram showing an example of the system configuration of a HUD device, and FIG. 12B is a diagram showing an example of a specific configuration of a main part of the HUD device. FIG. 13 is a diagram showing an example of the configuration of functional blocks of the control unit (HMI control unit). FIG. 14 is a diagram showing, in a table format, an example of setting the display priority for each display content (presentation information) according to a driving scene. 10 is a flowchart showing an example of an operation procedure of control for avoiding overlapping of display pixels in the HUD device.

The best mode described below is used to easily understand the present invention. Therefore, those skilled in the art should note that the present invention is not unduly limited by the mode described below.

Figure 1 is a diagram for explaining the principle of 3D display using the light field method (light reproduction method). In Figure 1, two 3D images IM10 and IM20 are displayed at different depth positions (depth distances) by a 3D display unit (also called a 3D display device, hereinafter simply called a 3D display unit) 230 using the light field method.

The stereoscopic display unit (sometimes called a light field display) 230 uses a flat display 210 using a liquid crystal panel or the like in combination with a lenticular lens 220 as an optical element 220, and controls the "position of lit pixels" on the flat display 210 to reproduce light rays defined at any position and direction.

Furthermore, the depth positions (or depth distances L10, L20) of the stereoscopic images IM10, IM20 as viewed from the stereoscopic display unit 230 side can be adjusted as appropriate by changing the "lighting pattern of the lit pixels (lit picture elements)" on the flat display. Note that in FIG. 1, the depth distances L10, L20 are the distances from the lens center of the lenticular lens that constitutes the stereoscopic display unit 230 to the respective stereoscopic images IM10, IM20. However, using the lens center as the reference is just an example, and the depth distances may be defined based on other points.

In addition, in Figure 1, the left eye AL and the right eye AR are positioned at the position where the light rays emitted by the stereoscopic images IM10, IM20 (reproduction light of the stereoscopic images IM10, IM20) are formed, and the distance from each eye AL, AR to each stereoscopic image IM10, IM20 is the image display distance L30, L40.

The horizontal direction is defined as the direction along the line segment connecting the left and right eyes AL, AR of an observer who observes the stereoscopic images IM10, IM20 in real space (or a viewer who visually recognizes the stereoscopic images IM10, IM20). In Fig. 1, a plurality of pixels (picture elements) G are arranged in the horizontal direction on the flat display 210. In Fig. 1, non-lit pixels are represented by open squares, and lit pixels are represented by filled-in squares.

The lighting (light emission) pattern PT1 of the pixels (display pixels) for displaying the stereoscopic image IM10 is different from the lighting (light emission) pattern PT2 of the display pixels for the stereoscopic image IM20. Due to this difference in pattern, the depth distances L10 and L20 of the stereoscopic images IM10 and IM20 can be different values.

In addition, the lighting pattern PT1 is located above the lighting pattern PT2 on the paper, and the horizontal positions of the lit pixels (lit pixels) are different. In other words, by adjusting the positions of the lit pixels, the horizontal positions of the two stereoscopic images IM10 and IM20 in three-dimensional space can be made different.

In Figure 1, lighting patterns PT1 and PT2 do not overlap, and there is no overlap of lit pixels. However, for example, if the depth distance of at least one of the stereoscopic images IM10, IM20 is changed, it is possible that lit pixels may overlap. In this case, the display pixels of stereoscopic image IM10 and the display pixels of stereoscopic image IM20 will collide, making it impossible to generate light field data by rendering (this will be discussed later).

Please refer to Figure 2. Figure 2 (A) shows an example of the basic configuration of a light field type (light ray reproduction type) stereoscopic display unit (stereoscopic display device) and an example of display (generation) of a stereoscopic image, and Figure 2 (B) shows an example of a HUD device using a stereoscopic display unit (stereoscopic display device) where a virtual image is displayed by light rays for the left eye and right eye emitted from a single light point that constitutes a stereoscopic image. In Figure 2, parts that are common to Figure 1 are given the same symbols (note that this also applies to the following figures).

The flat display 210 has a rectangular area (display area, or display surface) 215 in a plan view. A large number of pixels (picture elements) are arranged two-dimensionally in a grid pattern on this display surface 215. The horizontal direction of the rectangular display surface 215 corresponds to the horizontal direction, which is the direction along the line segment connecting the left and right eyes of an observer (or a viewer who views a stereoscopic image) who observes a stereoscopic image in real space. The vertical direction of the display surface 215 corresponds to the height of the observer (viewer) (referred to as the height direction). Also, the direction along the line segment (normal line) perpendicular to the display surface 215 and away from the display surface 215 is the depth direction. Also, in FIG. 2(A), a pixel (picture element) IML used to generate display light EL (1) for the left eye and a pixel (picture element) IMR used to generate display light ER (1) for the right eye are shown on the display surface 215.

As the optical element RS, in addition to the lenticular lens 220 shown above, a parallax barrier 225 may be used. However, these are examples and are not limited to these.

As shown in the upper left of Figure 2 (A), the lenticular lens 220 has a configuration in which cylindrical lenses are arranged horizontally, and has a light beam separation function that separates light beams for each of the left and right eyes.

The parallax barrier 225 is, for example, a set of narrow rectangular (rectangular) shields 225a-225n arranged at a predetermined pitch horizontally with gaps (slits) SL between them, and generates different image display lights (directional display light) for the left and right eyes by shielding part of the display light of the same image using the shields. It is similar to a lenticular lens in that it separates light rays for the left and right eyes.

When light separated by an optical element RS having a light beam separation function (in other words, reproduction light E(L1), E(R1) for each eye that reproduces an image) enters both eyes AL, AR located at the light imaging point, a person sees an apparent three-dimensional image IM at the point where convergence (intersection of light) occurs. In other words, this can also be seen as the three-dimensional image IM being displayed (or generated) by the three-dimensional display unit 230. In the example of Figure 2(A), the convergence angle is θc.

Next, refer to Figure 2(B). In Figure 2(B), an eye box EB is set in front of the viewer (such as the driver of a vehicle), and eye point EP(C) is located at the centre of the eye box EB. If virtual imaging planes PS(L) and PS(R) corresponding to the left and right eyes are set in front of the windshield 2, then a virtual image V(C) is located at the centre of the overlapping area. The convergence angle of the virtual image V(C) is θd, and the virtual image V(C) is recognised as a three-dimensional image by the viewer (user).

This three-dimensional virtual image V(C) is displayed (formed) as follows. That is, the reproduction light E(L1), E(R1) for each of the left and right eyes of the virtual three-dimensional image IM generated by the 3D display shown in FIG. 2(A) is reflected by a curved mirror (concave mirror, etc.) 171 included in the optical system of the HUD device (reflected at least once), and is projected (projected) onto the windshield 2 as display light E(L1), E(R1). The reflected light reaches both eyes of the viewer and forms an image in front of the windshield (projection target) 2, thereby displaying (forming) the virtual image V(C).

Next, let us refer to Figure 3. Figure 3(A) is a diagram for explaining the display of a stereoscopic image in a stereoscopic display section (stereoscopic display device) using a lenticular lens, and Figure 3(B) is a perspective view of a stereoscopic display section (stereoscopic display device) using a lenticular lens.

In Figure 3 (A), the lenticular lens 220 as an optical member is composed of a plurality of cylindrical lenses (cylindrical lenses) F1 to Fn as optical elements, which are arranged (arranged) at a predetermined pitch along the horizontal direction (direction W in Figure 4 (B)) to form a lens array structure that is periodic in the horizontal direction. The cylindrical lenses (F1 to Fn) as optical elements are vertically elongated cylindrical lenses (cylindrical lenses) whose surface (back surface) facing the flat display 210 is a flat surface that allows light to pass through, and whose opposite surface (front surface) is a spherical lens (however, this does not exclude the possibility of it being aspherical). Note that in the example of Figure 4 (A), the curvature of the spherical surface of the lens is uniform.

In Figure 3(A), each of the left-eye pixels (L pixels) L1 to Ln is arranged (formed) at a position corresponding to the left half of each of the cylindrical lenses F1 to Fn as optical elements. Each of the right-eye pixels (R pixels) R1 to Rn is arranged (formed) at a position corresponding to the right half of each of the cylindrical lenses F1 to Fn as optical elements. Note that one pixel is further made up of R (red), G (green), and B (blue) sub-pixels, but the sub-pixels are not shown in Figure 3(A).

See Figure 3 (B). The lenticular lens 220 shown in Figure 3 (B) has optical elements (cylindrical lenses) F1a to F8a that refract light arranged at a predetermined pitch along the lateral (horizontal) direction. This forms a light beam separation section that has a predetermined resolution in the lateral (horizontal) direction. In Figure 4 (B), the lateral (horizontal) direction is designated as H, the longitudinal (vertical) direction is designated as T, and the depth direction is designated as J.

Next, let us refer to Figure 4. Figure 4(A) is a diagram showing an example of the arrangement of display pixels on a flat display when two stereoscopic images are displayed at the same depth position (without overlap), and Figure 4(B) is a diagram showing an example of the arrangement of display pixels on a flat display when two stereoscopic images are displayed at different depth positions (with overlap).

In Figure 4 (A), the first and second stereoscopic images IM1 and IM2 are both displayed at a position S2, a distance D1 (image display distance D1) away from the viewpoint position S1 (position of the left and right eyes AL and AR).

Also, in FIG. 4A, four pixels (picture elements) IM1L, IMIR, IM2L, and IM2R are shown in the flat display 210. IM1L is a pixel (picture element) used to reproduce the light ray for the left eye of the stereoscopic image IM1, and IM1R is a pixel (picture element) used to reproduce the light ray for the right eye of the stereoscopic image IM1. IM2L is a pixel (picture element) used to reproduce the light ray for the left eye of the stereoscopic image IM2, and IM2R is a pixel (picture element) used to reproduce the light ray for the right eye of the stereoscopic image IM2. In this example, there is no overlap of display pixels.

Next, refer to FIG. 4(B). In the example of FIG. 4(B), the stereoscopic image IM2 is at a position S1' that is an image display distance D1' away from the viewpoint position S1. In this respect, it differs from FIG. 4(A). In the example of FIG. 4(B), the pixel IM1L used to reproduce the light ray for the left eye of the first stereoscopic image IM1 and the pixel IM2L used to reproduce the light ray for the left eye of the second stereoscopic image IM2 overlap. In this case, it is uncertain which one should be displayed, and therefore proper light field rendering cannot be performed. In the present invention, this problem is addressed by implementing priority display control based on display priority (priority).

Please refer to Figure 5. Figures 5(A) and (B) are diagrams showing examples of measures to be taken when display pixels overlap on a flat display when two stereoscopic images with different depth positions are displayed. In Figure 5(A), the display priority of the first stereoscopic image IM1 is higher than that of the second stereoscopic image IM2.

In Fig. 5(A), with regard to the overlapping pixels in Fig. 4(B) shown above, priority is given to pixel IM1L used to reproduce the light rays for the left eye of the first stereoscopic image IM1, and IM2L is ignored, depending on the priority of the image to be displayed (in other words, the priority of the information presented by that image). This means that pixel IM2L used to reproduce the light rays for the left eye of the second stereoscopic image IM2 is not lit. This avoids overlapping display pixels and enables the generation of light field data by rendering.

In the example of FIG. 5A, for the second stereoscopic image IM2, IM2L is not lit and only IM2R is lit. Therefore, it is not possible to display it as a stereoscopic image, and a non-stereoscopic image is displayed.

Next, refer to FIG. 5(B). In FIG. 5(B), two display examples, B1 and B2, are shown. In display example B1, the second stereoscopic image IM2 itself is hidden. This eliminates the overlap of display pixels. However, simply continuing to display display example B1 would mean that the presentation of information by the second stereoscopic image IM2 would not be possible indefinitely.

Therefore, when display example B1 is being displayed, notification information indicating that some items will not be displayed is also presented to the driver of the vehicle, etc., and when a predetermined time has elapsed and it is confirmed that IM1 has been viewed by the viewer, for example, the display transitions to display example B2, where the second stereoscopic image IM2 is displayed. This makes it possible to present information using the second stereoscopic image IM2. Then, after the predetermined time has elapsed, the display returns to display example B1. This resumes the presentation of information using the high-priority stereoscopic image IM1.

When the display example B2 is displayed, if the degree of notification necessity for the viewer of the hidden IM1 changes and increases, the high-priority IM1 may be displayed again (the low-priority IM2 may be hidden) as shown in the display example B1. The "degree of notification necessity" may be determined, for example, by the degree of danger derived from the degree of seriousness of the possible occurrence, the degree of urgency derived from the length of the reaction time required for the viewer (driver of the vehicle) to take a reaction action, the degree of effectiveness derived from the situation of the vehicle and the viewer (or other occupants of the vehicle 1), or a combination of these (the index of the degree of notification necessity is not limited to these). That is, the control unit 300 described later may have a function of calculating the degree of notification necessity based on information acquired via the I/O interface 741 described later.

Next, let us refer to Fig. 6. Fig. 6(A) is a diagram showing an example in which overlapping display pixels occurs when two stereoscopic images with different depth positions are displayed and one of the stereoscopic images is moved horizontally, and Figs. 6(B) and (C) are diagrams showing examples of measures to avoid overlapping display pixels.

6, the second stereoscopic image IM2 is, for example, a warning display (for example, a frame display surrounding the person) that calls the attention of a person who has entered the road, and the second stereoscopic image IM2 moves horizontally as the person moves. By detecting the direction and speed of movement of the person, etc., and performing predictive analysis based on the detection information, the horizontal movement of the second stereoscopic image IM2 can be predicted, and the corresponding movement of the display pixels can also be predicted.

Then, when the prediction determines that there is a possibility (preferably, a high possibility) of overlapping of display pixels, overlap suppression control (overlap avoidance processing) is implemented in advance, for example, at a point before overlapping of display pixels actually occurs.

In Fig. 6(A), a past time is t0, a current time is t1, and a time when movement is predicted is t2. The horizontal positions of the second stereoscopic image IM2 at each time are indicated as IM2(t0), IM2(t1), and IM2(t2). At time t1, there is no overlap of display pixels, but at time t2, it is predicted that there will be an overlap of display pixels IM1L and IM2L (see Fig. 4(B)).

In Figures 6 (B) and (C), processing to avoid overlap (overlap suppression control) is started in advance at time t1, which is a point before overlap of display pixels IM1L and IM2L occurs.

In FIG. 6B, pixel IM2L is not lit. This prevents overlapping of pixels. In this case, the displayed image IM2 is a non-stereoscopic image.

In FIG. 6C, at time t1, both display pixels IM2L and IM2R are turned off. Image IM2 is not displayed.

Next, reference is made to Figure 7. Figure 7(A) shows an example in which display pixels overlap when two stereoscopic images with different depth positions are displayed and one of the stereoscopic images is moved horizontally, Figure 7(B) shows an example of a pre-emptive measure when display pixel overlap is predicted, and Figures 7(C) and (D) show examples of measures to avoid display pixel overlap.

The situation in Fig. 7(A) is almost the same as that in Fig. 6(A). However, in Fig. 7(A), the distance between the position (IM2(t1)) of the second image IM2 at time t1 and the first image IM1 is D2, which is equal to or less than a predetermined distance (predetermined threshold distance) Dth.

In FIG. 7(B), the lighting brightness of display pixels IM2L and IM2R is reduced, resulting in reduced visibility of the second image IM2 (IM2 at time t1). In FIG. 7(C), display pixel IM2L is turned off. The second image IM2 becomes a non-stereoscopic image. In FIG. 7(D), display pixel IM2R is also turned off. The second image IM2 becomes non-display.

Here, for example, by continuously carrying out the controls of Fig. 7(B), (C), and (D), or by continuously carrying out the controls of Fig. 7(B) and (D), it is possible to carry out display control (fade-out control) in which the second image IM2 gradually disappears from time t1 to time t2. This makes it possible to prevent the second image IM2 from suddenly disappearing at time t2, and ensure natural vision.

Next, reference is made to Figure 8. Figure 8 is a diagram showing an example of the configuration of a HUD device that uses a light field type (light ray reproduction type) stereoscopic display unit (stereoscopic display device), and an example of a virtual image display.

8 has a flat display 210, a lenticular lens 220 as an optical element having a light beam separation function that is arranged in contact with or close to the flat display (display unit in a broad sense) 210, and a control unit (HMI control unit) 300 that controls image display (illumination of pixels) on the flat display 210. The flat display 210 and the lenticular lens 220 form a stereoscopic display unit (stereoscopic display device) 230.

The HUD device 100 also has an optical system 121 that includes a folding mirror 174 as a reflective member and a curved mirror (concave mirror, magnifying mirror) 171.

The curved mirror (concave mirror, magnifying mirror) 171 projects the display light (in other words, reproduction light) of the first image (first stereoscopic image) M (V1) virtually displayed by the stereoscopic display unit 230, and the display light (in other words, reproduction light) of the second image (second stereoscopic image) M (V2) onto the windshield 2, which serves as a projection target member (reflective translucent member) provided on the vehicle 1, through the transparent window 176. A portion of the projected light is reflected by the windshield 2 and projected onto the eye A of the driver, etc., and as a result, the first and second virtual images V1 and V2 are displayed (visually recognized) at positions in front of the vehicle 1 at virtual image display distances L1 and L2.

Here, the first virtual image V1 is, for example, the virtual image Q1 of a navigation arrow in Figures 9(B) to (D). The second virtual image V2 is, for example, the virtual image Q2 of an attention-attracting frame for attracting the attention of person 44 in Figures 9(B) to (D).

In FIG. 8, the curved mirror 171 can be rotated by the rotating unit (actuator) 175 to adjust the inclination as appropriate. Also, the inclination of the stereoscopic display unit 230 can be adjusted by the adjustment unit (actuator) 173.

Next, reference is made to Figure 9. Figure 9 (A) is a diagram showing an example of display priority (display priority order), Figures 9 (B) and (C) are diagrams showing an example of suppressing overlap between virtual images displayed by the HUD device by implementing measures to avoid overlap of display pixels, and Figure 9 (D) is a diagram showing an example of display when control to suppress overlap between virtual images is released.

Figure 9 (A) shows an example of a priority list that determines the display priority (priority order). The display priority is, from highest to lowest, as follows: warning display, navigation display, POI display, and other display (in Figure 9 (A), vehicle speed display and TSR (traffic sign recognition) information, which are non-overlapping content).

Based on this list, the control unit (HMI control unit) 300 of the HUD device 100 performs overlap suppression control regarding the display of overlapping or potentially overlapping content. Note that the display priority (priority order) may be determined (or changed) based on the notification necessity calculated based on information obtained from the I/O interface, instead of (or in addition to) the above-mentioned preset priority list.

In Figure 9 (B), in the virtual image display area 3 of the windshield 2, a virtual image Q0 displaying vehicle speed as non-overlapping content with a fixed virtual image display distance, a virtual image Q1 of a navigation arrow superimposed on the road surface 40, and a virtual image Q2 of a warning display (here, a warning frame) that calls attention to a person 44 entering the road are displayed.

The virtual image Q1 of the navigation arrow can be distinguished into a front portion Q1a that extends along the center line 42 (in other words, extends in the depth direction) and a rear portion Q1b that extends in the left-right direction (the width direction of the vehicle).

In addition, the distance W1 between the arrow element AR1 of the portion Q1a extending in the depth direction and the attention frame Q2 is smaller than a predetermined distance (here, Wth) as a threshold value. In other words, it can be determined that there is a possibility (high possibility in this case) of overlap of the display pixels described above because the attention frame Q2 approaches within a predetermined distance of the arrow element AR1. Therefore, the overlap suppression control described above is implemented. In FIG. 9(B), the visibility is reduced (for example, the display brightness is reduced) not only for the portion corresponding to the display pixel, but also for the entire arrow element AR1 including that portion. This makes it less likely that double vision will occur, resulting in a display that is easy to see.

In Figure 9 (C), person 44 is moving further into the road. As a result, the virtual image Q2 of the warning frame also moves to the right along the width direction of the vehicle 1 (this corresponds to the horizontal direction explained earlier). When a position is reached where overlapping of display pixels occurs, the entire arrow element AR1, including the portion displayed by those pixels, is hidden. This eliminates double vision and results in an easy-to-see display.

In Figure 9 (C), the viewer (driver) sees the attention warning frame Q2 and there is no longer any possibility of overlap, so the display restriction imposed by the overlap suppression control is lifted. As a result, the arrow elements AR1 and AR2 return to their normal display state.

Conventionally, when attempting to display content with different virtual image display distances (here, a warning display and a navigation display) close together horizontally, even when the pixels used to display the warning display at a designated position overlap with the pixels used to display the navigation display at a designated position and/or there was a high possibility of overlap, no rendering of light field data was performed taking these into consideration.

In this embodiment, appropriate display pixel overlap suppression control (overlap avoidance processing) is implemented, thereby improving the visibility of the displayed image (virtual image).

Next, reference is made to Figure 10. Figures 10(A) and (B) are diagrams showing an example in which overlap between virtual images displayed by a HUD device is suppressed by implementing measures to avoid overlap of display pixels.

In the example of Figure 10 (A), a vehicle speed display J1 of "80 km/h", a navigation arrow display J2, a warning display J3 of "speeding" and a warning mark J4 (collectively referred to here as "warning displays"), and a POI display J5 indicating the destination 46 are displayed.

The navigation arrow display J2 and the warning display J4 overlap, but in the overlapping area, the warning display J4, which has a higher priority, is given priority and is displayed in front. Also, in the example of Figure 10 (A), the overall visibility of the navigation arrow display J2 is reduced to make it easier to see.

In FIG. 10B, the navigation arrow display J4, which has a low priority, is hidden in its entirety. In this case, the attention mark J4 as a warning display becomes easier to see.

Next, reference is made to Figure 11. Figures 11(A) to (C) are diagrams showing an example in which overlap between virtual images displayed by a HUD device is suppressed by implementing measures to avoid overlap of display pixels.

Figure 11 (A) shows a first POI display (a display indicating the presence of a convenience store) J10 located on the near side (closer to vehicle 1) in the virtual image display area 3, a display J20 of TSR (traffic sign recognition) information such as "speed limit" and "school route" located behind J10, and a second POI display J30 (a display indicating the location of destination 47) located on the rear side (farther from vehicle 1).

In Figure 11 (A), J10 and J20 partially overlap, but for that overlapping portion, the display of J10, which has a higher display priority, is displayed preferentially.

In addition, in FIG. 11(B), J20, which has a low display priority, is hidden. However, to indicate (notify) the driver, etc. that there is content that has been hidden, a display of "1 item not displayed" is added.

In Fig. 11(C), after it is confirmed that J10 is visible, J20, which was not displayed until then, is displayed. After this, it is also possible to return to the state of Fig. 11(A).

Next, reference is made to Figure 12. Figure 12(A) is a diagram showing an example of the system configuration of a HUD device, and Figure 12(B) is a diagram showing an example of the specific configuration of the main parts of the HUD device.

The system shown in Figure 12 (A) has a display control unit (display control device) 300 included in the control unit 290, an object detection unit 801, a vehicle information detection unit 803, the three-dimensional display unit 230 previously shown in Figure 8, a first actuator 177, and a second actuator 179.

The control unit (HMI control unit) 300 has an I/O interface 741, a processor 742, and a memory 743. The control unit (HMI control unit) 300, the object detection unit 801, and the vehicle information detection unit 803 are connected to a communication line (BUS, etc.).

The first actuator 177 and the second actuator 179 can be used as the rotating unit (rotating mechanism) 175 and the adjustment unit 173 shown in Figure 8. These can also be considered as an adjustment system for the optical system or the display unit.

The object detection unit 801 may be configured, for example, by an external sensor or an external camera provided on the vehicle 1. The vehicle information detection unit 803 may be configured, for example, by a speed sensor, a vehicle ECU, an external communication device, a sensor for detecting the position of the eyes, a yaw rate sensor for detecting the pitch angle (inclination angle) of the vehicle 1, or a height sensor. The display control unit (display control device) 300 appropriately performs predetermined image processing based on the detection information from the object detection unit 801 and the information from the vehicle information detection unit 803, thereby achieving both an appropriate display of perspective and a reliable notification of information to the viewer (driver, HUD user).

In addition, one or more processors 742 can, for example, acquire position information of the road surface 40, and based on the acquired information, drive at least one of the first and second actuators 177, 179 to adjust the virtual image display position, etc.

Next, refer to Fig. 12 (B). As shown in Fig. 12 (B), the control unit (HMI control unit) 300 has a light field rendering unit 302 and a display drive unit 336. The light field rendering unit 302 has an input/output interface (I/F) 304, an image generation unit (light field data generation unit) 310, a multi-viewpoint image storage unit (image database) 312, a left-eye image buffer 332, and a right-eye image buffer 334.

The multi-viewpoint image storage unit (image database) 302 stores, for example, samples of multi-viewpoint images (original images) for the display object.

The image generating unit (light field data generating unit) 310 generates light field data. The generated data is temporarily stored in image buffers 332, 334 for the left and right eyes, and then supplied to the display unit (flat display) 210 via the display unit driving unit 336 as a left eye parallax image GL and a right eye parallax image GR.

The vehicle 1 also has an pupil imaging camera 900 that images the user's eyes, a gaze detection unit (viewpoint position detection unit) 902 that detects the user's viewpoint position, a visual confirmation detection unit (visual confirmation unit) 903 that detects (confirms) that the viewer has viewed a specific display, a surrounding imaging camera 17, and a driving scene determination unit 19 that includes an image processing unit 21.

Next, reference is made to FIG. 13. FIG. 13 is a diagram showing an example of the configuration of functional blocks of the control unit (HMI control unit). The control unit (HMI control unit) 300 has, for example, as functional blocks, a display mode determination unit 302, an overlap detection unit 303 that detects at least one of overlap and overlap possibility of display pixels, an overlap mode detection unit 304 that detects the type of overlap mode, an overlap suppression control unit 305, and an image generation control unit 306.

Here, the overlap suppression control unit 305 performs overlap suppression control. The image generation control unit 306 controls the generation operation, for example, by rendering light field data.

Next, let us refer to Figure 14. Figure 14 is a diagram showing, in table form, an example of setting the display priority for each display content (presentation information) according to the driving scene.

In FIG. 14, the driving scenes determined by the driving scene determination unit 19 (see FIG. 12(B)) are shown as follows: a first scene of a city on a clear day (city or traffic volume is equal to or greater than a predetermined value), or a highway (city) on a clear day, or a crowded intersection, or a school route; a second scene of a city on a clear day (countryside or traffic volume is less than a predetermined value), or a highway (countryside) on a clear day, or when the driver is looking away or returning from looking away, or a location or area where accidents frequently occur; a third scene of a city at night (city or traffic volume is equal to or greater than a predetermined value), or a highway at night (city); a fourth scene of a city at night (countryside or traffic volume is less than a predetermined value), or a highway at night (countryside); a fifth scene of a traffic jam while stopped; a sixth scene of a case where the vehicle is restricted in its travel (including a U-turn is prohibited or under construction); and a seventh scene of an automatic driving scene. It is not necessary to include all seven driving scenes, but it is preferable to include at least four of them.

In addition, FIG. 14 shows warning display, navigation display, POI display, and traffic sign recognition (TSR) display as display contents (information presented by display) to which priority is assigned.

Numbers are also assigned inside the table in FIG. 14, with lower numbers indicating higher display priority (priority order). In FIG. 14, the display priority of each of the four display contents corresponding to the seven driving scenes is predefined in list format (table format). This allows the priority of the display contents (display information) to be updated quickly according to each driving scene, enabling appropriate display control.

In principle, the priority order is as follows, from highest to lowest: warning display, navigation display, POI display, TSR information, etc. However, in the sixth scene, as an exception, the priority of TSR information, etc. is set to "1".

In addition, in Figure 14, the warning display is further divided into a first warning for high relative velocity objects (including oncoming vehicles and pedestrians), a second warning for low relative velocity objects (including vehicles traveling in the same direction), and a third warning for notifications regarding conditions around the vehicle (including notifications of natural disasters and traffic accidents).

The warning display is further divided into three types (first, second, and third warnings), and a priority is set for each type depending on the driving scene. Here, the first warning has the highest priority, and as for the second and third warnings, the second warning has a higher priority than the third warning in the first to sixth scenes, but in the seventh scene (when driving autonomously), taking into consideration that the driver is not generally involved in driving, the second and third warnings are set to the same priority (both are set to a priority of "3" in Figure 14).

Even when there are multiple warning displays and the display pixels of one warning display overlap with the display pixels of another warning display, the system can prevent pixel overlap according to the priority (priority order) that takes into account the driving scene set for each warning content (warning type). Since warnings can always be displayed appropriately, safety is improved.

Next, reference is made to Figure 15. Figure 15 is a flowchart showing an example of a control operation procedure for avoiding overlapping of display pixels in a HUD device.

For example, the light field rendering unit 302 in FIG. 12 (B) first sets a first display position that includes at least the depth position of a first image showing the first information, and a second display position that includes at least the depth position of a second image showing the second information (step S1).

Next, it is determined whether a first pixel used when displaying the first image at the first display position and a second pixel used when displaying the second image at the second display position overlap, or whether there is a possibility of overlap (step S2).

Next, if it is determined that there is a high possibility that the first pixel and the second pixel overlap, the image having the higher priority between the first information and the second information is displayed preferentially, and overlap suppression control (overlap avoidance processing) is implemented, which includes not displaying at least the overlapping pixels of the image having the lower priority (step S3).

Thus, according to the present invention, in a HUD device having a light field type stereoscopic display unit, it is possible to avoid (suppress) a situation in which proper light field rendering cannot be performed due to overlap between pixels for displaying one image and pixels for displaying another image.

In this specification, the term vehicle may be broadly interpreted as a vehicle. Navigation terms (e.g., signs, etc.) are also broadly interpreted, taking into account, for example, the perspective of broad navigation information useful for vehicle operation. HUD devices are also intended to include those used as simulators (e.g., aircraft simulators, game consoles, etc.). The types of display units and optical components are not limited to those in the above embodiments, and various types may be adopted.

The present invention is not limited to the exemplary embodiments described above, and a person skilled in the art could easily modify the exemplary embodiments described above to the extent that they fall within the scope of the claims.

1: vehicle (own vehicle), 2: projection target (windshield, etc.), 3: HUD display area, 17: surrounding image capturing camera, 19: driving scene determination unit, 21: image processing unit, 22: viewer (observer, driver, user), 300: control unit (HMI control unit), 36: attribute determination unit for display object, 40: road surface, 100: HUD device, 171: curved mirror (concave mirror, etc.), 210: flat display as display unit, 220: Optical member (lenticular lens, etc.), 230: Stereoscopic display unit (3D display unit), 290: Control device, 300: Control unit (HMI (human interface) control unit), 310: Image generation unit (light field data generation unit), 900: Pupil imaging camera, 902: Line of sight detection unit, 903: Vision detection unit (visual confirmation unit), IM1, IM2: First and second images, first and second display images, or first and second stereoscopic images

Claims (10)

A head-up display (HUD) device for displaying a virtual image, comprising:
a light field type stereoscopic display unit including a display and an optical member and reproducing light rays of a stereoscopic image;
an optical system that projects the light beam reproduced by the stereoscopic display unit onto a projection target;
A control unit that controls display of an image on the display;
having
When the distance between the stereoscopic display unit and the stereoscopic image is defined as a depth distance, and the direction along the depth distance when the stereoscopic image is viewed from the stereoscopic display unit is defined as a depth direction,
The control unit is
setting a first display position including at least a position in a depth direction of a first image showing the first information, and a second display position including at least a position in a depth direction of a second image showing the second information;
determining whether or not a first pixel on the display used when displaying the first image at the first display position overlaps with a second pixel used when displaying the second image at the second display position, and/or whether there is a possibility of overlap;
If it is determined that the first pixel and the second pixel overlap or are likely to overlap,
prioritize the display of the image having a higher display priority, and perform overlap suppression control including turning off or reducing the brightness of at least the pixels in the overlapping portion of the image having a lower display priority;
A head-up display device. The control unit is
The head-up display device according to claim 1, characterized in that when at least one of the first and second images is a dynamic image corresponding to a virtual image superimposed on a moving object, the possibility of the overlap is determined based on a prediction of the movement of the object. The control unit is
3. The head-up display device according to claim 1, wherein the overlap suppression control is performed by prioritizing the displays in the order of highest priority, namely, a warning display, a navigation display, a POI (Point Of Interest) display, and other displays. Further comprising a driving scene determination unit,
4. The head-up display device according to claim 1, wherein the control unit variably controls a priority order of the display images in accordance with a driving scene. Further comprising a visual detection unit,
The control unit is
After displaying one of the images in accordance with the priority order, when the visibility detection unit detects that the displayed image is viewed by a viewer, at least a part of the display restriction of pixels of the other image, the display of which has been restricted, is lifted.
The head-up display device according to any one of claims 1 to 4. The control unit is
When a pixel for displaying the first image and a pixel for displaying the second image are not overlapped but are within a predetermined distance, or when it is determined that a distance between the pixels has become closer to within the predetermined distance due to a movement of at least one pixel, the overlap suppression control is performed on the pixel of the image having a lower priority.
6. The head-up display device according to claim 1, wherein the head-up display device is a vehicle-mounted display. The control unit is
when it is determined that the pixels for displaying the first image and the pixels for displaying the second image do not overlap but that the two pixels have come close to each other within a predetermined distance due to the movement of at least one of them, and the distance between the two pixels becomes smaller over time, a fade-out process is performed to gradually decrease the luminance of the pixels of the image having a lower priority.
7. The head-up display device according to claim 1, wherein the head-up display device is a head-up display. The control unit is
displaying a notification image indicating that a restriction is imposed on display of an image with a low priority due to the overlap suppression control;
The head-up display device according to any one of claims 1 to 7. The driving scene determined by the driving scene determination unit is
A first scene of a city area on a sunny day (urban area or traffic volume above a certain value), or a highway on a sunny day (urban area), or a busy intersection, or a school route;
A second scene in a city on a clear day (in the countryside or with traffic volume below a certain level), or on a highway on a clear day (in the countryside), or when the driver is looking away or returning from looking away, or in a location or area where accidents frequently occur;
A third scene of a nighttime urban area (urban area or area with traffic volume above a certain value) or a nighttime highway (urban area);
A fourth scene of a nighttime urban area (rural area or traffic volume below a certain value) or a nighttime highway (rural area);
The fifth scene, during a traffic jam stop,
The sixth scene is when there are restrictions on vehicle movement (including no U-turns or construction work).
The seventh scene during autonomous driving,
at least four of
As indications to which priority is given,
Warning signs,
Navigation display,
POI display,
Traffic Sign Recognition (TSR) indications;
The head-up display device according to claim 4 . The warning display is:
A first warning about high relative velocity objects (including oncoming vehicles and pedestrians);
A second warning for low relative velocity objects (including vehicles traveling in the same direction); and
A third warning regarding notifications regarding the situation around the vehicle (including notifications of natural disasters and traffic accidents);
Including,
The first warning is set to have a higher priority for display than the second and third warnings,
Regarding the second warning and the third warning, the second warning is set to have a higher priority in the first to sixth scenes, but the second warning and the third warning are set to have the same priority in the seventh scene.
The head-up display device according to claim 9 .

Images