Head-up display device

Abstract

The present invention provides a head-up display (HUD) device that alleviates a burden (including a psychological burden) that is imposed on a viewer in certain situations such as when the viewer is looking forward to see into the distance but the line of sight is obstructed by an image (virtual image) produced by the HUD device superimposed onto the front real view (foreground), consequently, the visibility of the foreground is reduced, visual attention is diverted to the image (virtual image) and visual attention on the foreground by the viewer is thus lowered, or the image (virtual image) feels annoying, for example. The HUD device includes an image display unit (140), an optical system (129, 133), and a control unit (120), wherein the control unit (120) sets a first display area (101) and a second display area (102) in a virtual display area (100) of a real segment in front of the viewer, and lowers the visual attraction of a display object (NV10 to NV30, CU1) displayed in the first display area (101).

Description

[Technical Field]

[0001] The present invention relates to a head-up display (HUD) device mounted on a vehicle such as an automobile. [Background technology]

[0002] In conventional HUD devices, the visibility of the image (virtual image) is usually designed to be approximately constant across the entire display area. For example, the fact that inventions that take uniformity into consideration have been proposed suggests that the above items were taken into consideration during the design process.

[0003] For example, Figure 10 of Patent Document 1 shows an example in which a HUD device simultaneously displays images (virtual images) of a navigation arrow, a warning display indicating approaching people, and a vehicle speed display. Patent Document 1 refers to this image (virtual image) as a presence notification image.

[0004] Furthermore, Patent Document 1 mentions eye-catching features in, for example, paragraph

[0062] . However, it only states that "as the time until a person or the like enters becomes shorter, the presence notification image may be changed to a more eye-catching image." For example, there is no specific mention of designing a plurality of images (virtual images) to have different eye-catching features instead of designing them to have uniform eye-catching features, or of reducing the eye-catching features of some display targets (display objects). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-24561 Summary of the Invention [Problem to be solved by the invention]

[0006] The present inventors have investigated a HUD device that can simultaneously display a plurality of diverse images (virtual images) over a fairly wide area, and as a result have made the following novel findings.

[0007] For example, if a viewer is looking ahead as if looking into the distance, their line of sight may be obstructed by an image (virtual image) from the HUD device that is superimposed on the actual scene (foreground) ahead, which may result in, for example, reduced visibility of the foreground, visual attention being drawn to the image (virtual image), reducing the viewer's visual attention to the foreground, or the viewer feeling that the image (virtual image) is annoying, thereby increasing the viewer's burden (including psychological burden).

[0008] HUD devices aim to improve convenience by presenting useful information to the viewer, but the display may interfere with the view of the actual scenery, such as the view ahead, or may distract the viewer from the actual scenery, or may cause stress when driving a vehicle for long periods of time. This is an important issue that relates to the technical significance of HUD devices, and there is room for improvement in this regard.

[0009] The present invention aims to provide a HUD device that can reduce burdens (including psychological burdens) on a viewer, such as when a viewer who directs their gaze forward as if looking into the distance has their line of sight obstructed by an image (virtual image) from the HUD device that is displayed superimposed on the real scene (foreground) ahead, resulting in reduced visibility of the foreground, visual attention being drawn to the image (virtual image) and reducing the viewer's visual attention to the foreground, or the viewer feeling annoyed by the image (virtual image).

[0010] Other objects of the present invention will become apparent to those skilled in the art by referring to the following exemplary aspects and best modes, as well as the accompanying drawings. [Means for solving the problem]

[0011] In order to facilitate an understanding of the outline of the present invention, the following examples are given of embodiments according to the present invention.

[0012] In a first aspect, a head-up display (HUD) device includes: an image display unit that displays an image; an optical system that projects light of the image displayed by the image display unit toward a projection target, thereby allowing the viewer to view a virtual image of the image within a virtual display area in a real space in front of the viewer; a control unit that controls display of the image on the image display unit; and A first gaze direction is a gaze direction of the viewer facing forward at a depression angle of 0 degrees, starting from an eye position of the viewer or a reference position corresponding to the eye position, A second line of sight direction is a direction of the viewer's line of sight that is inclined at a depression angle of m degrees (m is an integer greater than 0) from the first line of sight direction, a direction perpendicular to the first line of sight direction and along a line segment connecting the left and right eyes of the viewer is defined as a left-right direction; When a direction along a line segment perpendicular to the first line of sight direction and the left-right direction is defined as a vertical direction or height direction, a direction away from the ground or a surface equivalent to the ground in the real space is defined as an upward direction, and a direction approaching the ground is defined as a downward direction, The control unit dividing the virtual display area into a first display area closer to the first line of sight and a second display area other than the first display area, based on an intersection point between the virtual display area and the second line of sight; and setting the first display area and the second display area; Control is performed to make the visibility of a first display object displayed in the first display area lower than the visibility of a second display object displayed in the second display area.

[0013] In the first aspect, a virtual display area (sometimes simply referred to as a display area in this specification) of a HUD device in the real space ahead is divided into a first display area and a second display area, and the visibility of a display target (display object) is reduced in the first display area. This prevents the display by the HUD device from interfering with the viewing of the background (real scenery) while driving, thereby reducing annoyance and stress, for example.

[0014] Here, the first display area is an area in which an image (virtual image) that is thought to be often superimposed (overlaid) on a relatively distant real scene in the virtual display area is placed. When driving a vehicle, it is said that it is important to maintain a wide field of vision by looking into the distance while also keeping an eye on nearby areas and surroundings. In particular, during long drives, the driver spends a lot of time paying attention to distant objects, so visibility of the distant real scene (foreground) is an important factor for safe driving. In consideration of this, the visibility of the image (virtual image) in the first display area is reduced so as not to obstruct the view of the background, excessively distract the viewer from the background, or create a sense of incongruity with the background, causing stress, thereby ensuring a comfortable driving experience.

[0015] The first display area is a display range corresponding to the range of, for example, 0 to m degrees (m is an integer greater than 0, for example, m=2) of the depression angle of the viewer's line of sight (which can be expressed, for example, as the angle between the direction of the line of sight when looking down at an object and the horizontal plane at eye height (or an equivalent position)), and in this range, the viewer's (person's) line of sight is approximately parallel to the ground or an equivalent surface (such as the road surface, and in the case of a simulation device or game device, this also applies to the floor surface of the installation location), and is presumably looking straight ahead (or slightly lowering their eyes) and looking into the distance. Therefore, by ensuring good visibility of the foreground in this state, it is possible to effectively alleviate (reduce) the viewer's psychological burden, etc.

[0016] In a second aspect dependent on the first aspect, The first display area and the second display area are the first display area is separated from the second display area by a line segment that passes through an intersection of the virtual display area and the second line of sight, extends in the left-right direction, and crosses the virtual display area, and the first display area is located above the second display area; Or, the virtual display area is separated by a boundary line formed by a part of a line segment that passes through an intersection of the virtual display area and the second line of sight, extends in the left-right direction, and crosses the virtual display area, and the first display area is located above a part of the second display area; Or, The virtual display area may be separated by a partial arc or curved line passing through the intersection of the virtual display area and the second line of sight direction, and the first display area may be located above the second display area.

[0017] In the second aspect, the boundary separating the first and second display areas is determined based on the position of the intersection between the display area and the second viewing direction, and the aspects include, for example, when the entire line segment passing through the intersection and crossing the display area from left to right becomes the boundary line, when a part of that line segment forms (part of) the boundary line, or when a partial arc or curve passing through the intersection becomes the boundary line.

[0018] In either case, at least a portion of the second display area is located below the first display area, which is the area that reduces the visibility of the first display area. Relatively speaking, the first display area is located above the second display area.

[0019] As mentioned above, reducing the visibility of the background (real scenery) by reducing the eye-catching effect and ensuring the visibility of relatively distant real scenery leads to a reduction in the visual burden on the viewer, so the first display area is set to the upper range within the display area (the range related to the visibility of relatively distant real scenery).

[0020] In a third aspect dependent on the first or second aspect, The control unit In the first display area, the degree of visibility may be varied depending on the position in the vertical direction, so that the visibility of a display object placed at the top is lower than that of a display object placed at the bottom.

[0021] In a third aspect, the visual appeal of a display object displayed (placed) at the top of the first display area is lower than that of a display object displayed (placed) at the bottom, and the further away the viewer looks, the less attention the display object itself receives, allowing the viewer to clearly see the distant actual scene. This is a suitable example for effectively reducing stress on the viewer. The change in visual appeal (visibility) in the vertical direction may be continuous or gradual.

[0022] In a fourth aspect dependent on any one of the first to third aspects, The control unit When a display object is displayed across the first display area and the second display area, the overall conspicuousness of the display object may be reduced.

[0023] In the fourth aspect, the overall conspicuousness of a display object that is displayed across the first and second display areas (for example, a navigation arrow that is displayed so as to be superimposed on the road surface, or a navigation arrow that is displayed so as to be superimposed on the road surface or a navigation arrow that is displayed so as to be floating in the air) is reduced.

[0024] Since the first display area is also displayed, it is preferable to increase the visibility of the background (scenery and foreground) at a relatively long distance to the viewer, and if there is a difference in the degree of visibility between the first and second display areas, it may be perceived as unnatural by the viewer, which may increase the visual burden. Therefore, the visibility is reduced overall.

[0025] In a fifth aspect dependent on any one of the first to fourth aspects, The head-up display may be mounted in a vehicle.

[0026] In a fifth aspect, the head-up display (HUD) device is used in a vehicle, which can provide the effect of reducing eye fatigue during long driving, for example.

[0027] In a sixth aspect dependent from the fifth aspect, The control unit If the direction in which the front end of the vehicle faces shifts diagonally upward from a standard state, a correction process may be performed to suppress fluctuations in the first line of sight direction in accordance with the shift diagonally upward.

[0028] The sixth aspect shows an example of a preferable countermeasure when the direction in which the front end of the vehicle faces is shifted obliquely upward from the standard state.

[0029] The pitching angle of a vehicle may change depending on the balance of the vehicle's occupants and the balance of luggage. For example, if the vehicle is a truck and there is a large amount of cargo in the rear bed, the front of the truck may be facing diagonally upward (upward) from the standard (normal) state. In this case, the display area virtually provided in the real space in front of the viewer (driver) also moves upward, which in turn turns the viewer's (driver's) line of sight upward, making it easier to see further away. In this case, it is preferable to expand the first display area to broaden the range over which the distant real scene can be easily seen. However, without any ingenuity, the sizes of the first and second display areas (or the proportions of each area) remain the same, and the entire display area simply moves upward.

[0030] Therefore, in this aspect, even when the front end of the vehicle is facing upward, the above-mentioned first line of sight direction, which is the reference for determining the first display area, is suppressed from shifting upward, and a state of, for example, preferably a depression angle of 0 degrees is maintained. In other words, a process (correction process) is performed to correct the upward shift and suppress fluctuations in the first line of sight direction so as to approach a depression angle of 0 degrees. Note that the degree to which the front end of the vehicle is shifted diagonally upward can be determined, for example, based on information from a pitch angle sensor provided in the vehicle.

[0031] When the upward shift of the first line of sight direction is suppressed (preferably maintained at a depression angle of 0 degrees), the display area moves upward, and therefore the position of the intersection with the second line of sight direction moves relatively downward. Because the intersection position is also an important factor in determining the position of the boundary line between the first and second display areas, moving the intersection position downward expands the first display area, and therefore the range in which the distant actual scene is easy to see (the range in which conspicuity is reduced) expands, resulting in the effect of maintaining a state in which the viewer (driver) can easily see the actual scene ahead and around (in other words, maintaining good visibility, etc.).

[0032] In a seventh aspect dependent on the fifth or sixth aspect, The control unit When the speed of the vehicle is slow, the first display area may be moved further downward than when the speed of the vehicle is fast.

[0033] In the seventh aspect, since the gaze point (gaze position) of the viewer (driver) tends to be lower when the vehicle is traveling at a low speed compared to when the vehicle is traveling at a high speed, the first display area is also moved downward accordingly. This makes it possible to appropriately set the first display area, which is a range that reduces conspicuousness, even if the line of sight (line of sight) is lowered when traveling at a low speed.

[0034] In an eighth aspect dependent on the fifth or seventh aspect, The control unit When the speed of the vehicle is slow, the first display area may be expanded downward compared to when the speed of the vehicle is fast.

[0035] In the eighth aspect, when the vehicle is traveling at a low speed while driving, the viewer's (driver's) point of gaze (gaze position) tends to be lower than when traveling at a high speed, and accordingly, the first display area is widened (expanded) downward. This makes it possible to appropriately set the first display area, which is a range that reduces visibility, even if the viewer's (driver's) line of sight (gaze position) is lowered at low speeds. Furthermore, in this aspect, since the upper position of the first display area does not change, even if the viewer's (driver's) line of sight is turned upward, the first display area is in the direction of the upward line of sight (gaze position), and good visibility of the actual scene can be maintained.

[0036] In a ninth aspect dependent on any one of the fifth to eighth aspects, The control unit The first display area may be expanded in the left-right direction when the vehicle turns right or left, and may be expanded to the right when turning right and to the left when turning left.

[0037] In the ninth aspect, when a vehicle turns right or left while driving, the line of sight (line of sight) moves to the right or left, and accordingly the first display area also moves to the right or left accordingly. This makes it possible to appropriately set the first display area, which is a range that reduces conspicuousness, even when turning right or left.

[0038] In a tenth aspect dependent on any one of the first to ninth aspects, The optical system has a curved mirror, and the curved mirror rotates in response to a change in the eye position of the viewer, and the position of the virtual display area in real space changes in the vertical direction accordingly. Or, A vertical change in the virtual display area and a vertical change in the reference position of the first line of sight result in The position in the up-down direction of the intersection between the virtual display area and the second line of sight may be changed, thereby adjusting the area of ​​the first display area.

[0039] In the tenth aspect, the extent (size, area) of the first display region can be adaptively adjusted according to the viewer's eye position in the up-down direction (height direction).

[0040] In response to changes in eye position, for example, a curved mirror (concave mirror, etc.) included in the optical system rotates, automatically adjusting so that display light is incident on the eye position. At this time, when the eye position becomes higher (upward), the line of sight (line of sight) changes to looking down (the depression angle changes to increase), so the position of the display area also moves downward, and when the eye position becomes lower (downward), the line of sight (line of sight) changes to looking far ahead (the depression angle changes to decrease), so the position of the display area also moves upward, and when the eye position is somewhere between the above-mentioned upper and lower positions, the display area also changes to be located somewhere between the above-mentioned positions.

[0041] Here, if the height position of the above-mentioned first line of sight direction is fixed, for example (for example, fixed at the height of the middle eye position and not changed), the position of the intersection changes according to the change in the height position of the display area, and as a result, the first display area, which is the range that reduces the eye-catchingness, expands or shrinks, and its size is automatically adjusted.

[0042] For example, when the eye position is high, the direction of the line of sight tends to decrease and the viewer tends to look at nearby objects, so the first display area related to the viewing of distant real scenes automatically narrows. On the other hand, as the eye position decreases and the direction of the line of sight increases, the viewer tends to look further into the distance, so the range of the first display area automatically widens accordingly. In this way, the range (size, area) of the first display area is automatically and appropriately adjusted according to the eye position.

[0043] In the above description, the height position of the first line of sight is fixed, but the height of the first line of sight can also be moved appropriately to match the actual eye height position. In this case, the fluctuation in the position of the intersection tends to be greater. In this case, as in the above example (example in which the height position of the first line of sight is fixed), the size (area) of the first display area changes depending on the eye position. However, in this example, because the fluctuation range of the intersection position is large, for example, if the eye position becomes higher and the line of sight becomes a downward direction, it is possible that the first display area related to viewing the distant actual scene will not be set (the area of ​​the first display area will be zero).

[0044] In this way, the vertical position of the intersection between the display area and the second line of sight can be changed by changing the display area in the vertical direction, or by combining the vertical change of the display area with the vertical change of the reference position of the first line of sight, thereby automatically adjusting the area (size) of the first display area.

[0045] In an eleventh aspect dependent on any one of the first to tenth aspects, Reducing the visibility of the display object Low brightness, and, Reducing the size, and, Low contrast, and, Changing the color palette from primary to pale colors, and, In the blinking state, slow down the blinking rate or stop blinking; and, shortening the display duration with respect to the period during which the same display object is displayed; and, Regarding the display of moving images, at least one of slowing down the speed, slowing down the cycle, and displaying still images is implemented. and, hiding or reducing a highly visible part of the display object; and, changing the appearance of the display object; This may be achieved by at least one of the following:

[0046] The eleventh aspect illustrates a method for reducing the visual appeal of a display object. For example, by appropriately combining these methods, the effect of reducing visual appeal can be enhanced. Furthermore, by adopting an appropriate visual appeal reduction method depending on the display mode of the display object, the driving situation, or the like, it is possible to adjust the visual appeal to an appropriate level while maintaining a certain degree of visibility of the display object.

[0047] In a twelfth aspect dependent on any one of the first to tenth aspects, Reducing the visibility of the display object The color of the display object is set to an opposite color, including a complementary color, of the color of the actual scene on which the display object is superimposed to suppress a decrease in visibility, Alternatively, this may be achieved by at least one of lowering the brightness, reducing the size, hiding or reducing the highly visible parts of the display object, and changing the appearance of the display object.

[0048] In the twelfth aspect, as a preferred example of adjusting the eye-catching effect, the color (hue) of the displayed object is set to a color opposite to, including a complementary color, the color of the actual background, thereby maintaining a high contrast to some extent and ensuring a certain degree of visibility of the image (virtual image) displayed by the HUD device. If the display itself becomes invisible or difficult to see, the meaning of displaying a virtual image is lost, so the visibility of the image (virtual image) is ensured to some extent by visual contrast.

[0049] Furthermore, for example, if the actual scene is a dark color close to a primary color, the image (virtual image) will be difficult to see, but if it is an opposing color including a complementary color, the contrast will be high and the image (virtual image) will still be visible. Furthermore, if the viewer looks away from the actual scene, a complementary color afterimage will appear, but if the image (virtual image) is a complementary color, even if a complementary color afterimage appears, it will not feel particularly strange because it is the same color, and in this respect too, the effect of reducing visual stress can be expected.

[0050] On the other hand, by implementing at least one of the following: lowering the brightness, reducing the size, hiding or reducing the size of the display object's most eye-catching parts, and changing the appearance of the display object, it is possible to effectively reduce the overall visibility of the display object and avoid interfering with the visibility of the background (real scenery).

[0051] Those skilled in the art will easily understand that the exemplified embodiments according to the present invention can be further modified without departing from the spirit of the present invention. [Brief explanation of the drawings]

[0052] [Figure 1] Figure 1(A) shows an example in which the display area is divided into first and second display areas and the eye-catching image (virtual image) in the first display area is reduced, and Figure 1(B) shows an example in which the eye-catching image of a navigation arrow displayed across the first and second display areas, superimposed on the road surface, is reduced. [Figure 2] FIG. 2 is a diagram showing an example in which the eye-catchingness of a display object (virtual image) is reduced. [Figure 3] FIG. 3(A) is a diagram showing an example in which the visual appeal is changed depending on the position in the vertical direction within the first display area, and FIG. 3(B) is a diagram showing another example. [Figure 4] Figure 4(A) is a diagram showing an example of the position of the first display area when driving at a standard speed, Figure 4(B) is a diagram showing an example of moving the first display area downward when driving at a low speed, and Figure 4(C) is a diagram showing an example of expanding the first display area downward when driving at a low speed. [Figure 5]Figures 5(A) and (B) show an example in which a first display area is set in a portion of the upper side of the display area, and Figures 5(C) and (D) show an example in which the first display area is expanded to the right when turning right. [Figure 6] FIG. 6(A) is a diagram showing an example of setting the first display area by setting the height position of the first line of sight to the midpoint of the eyebox, and FIG. 6(B) is a diagram showing an example of setting the first display area by setting the height position of the first line of sight to the eye height. [Figure 7] Figure 7(A) is a diagram showing an example of dividing the first and second display areas by a boundary line of a partial arc, and Figure 7(B) is a diagram showing an example of dividing the first and second display areas by a straight line segment that crosses the display area from left to right. [Figure 8] FIG. 8 is a diagram showing an example in which a rectangular first display area is set in a part of the upper side of the display area. [Figure 9] Figure 9(A) is a diagram showing an example in which a first display surface area corresponding to the first display area and a second display surface area corresponding to the second display area are set on the display surface of the image display unit, and Figure 9(B) is a diagram explaining the process of reducing conspicuousness when an image (real image) of a display object is placed in each of the first and second display surface areas. [Figure 10] Figures 10(A) to (D) are diagrams showing an example of setting the first and second display areas when the height position of the first line of sight direction is fixed and the height position of the display areas is changed depending on the eye position. [Figure 11] Figures 11(A) to (D) are diagrams showing other examples of setting the first and second display areas when the height position of the first line of sight direction is fixed and the height position of the display area is changed depending on the eye position. [Figure 12] Figures 12(A) to (C) are figures showing an example of adjusting the size of the first display area by performing a correction process that prevents the first line of sight direction from facing upward when the front end of the vehicle faces upward. [Figure 13] FIG. 1 is a diagram illustrating an example of the internal configuration of a HUD device. [Figure 14] FIG. 1 is a diagram illustrating an example of a system configuration of a HUD device. [Figure 15] 10 is a flowchart showing an example of a procedure for setting first and second display areas. DETAILED DESCRIPTION OF THE INVENTION

[0053] The best mode described below is used to facilitate understanding of the present invention. Therefore, those skilled in the art should note that the present invention is not unduly limited by the embodiment described below. In the following description, the "virtual display area" may be simply referred to as the "display area."

[0054] Figure 1(A) shows an example in which the display area is divided into first and second display areas and the eye-catching image (virtual image) in the first display area is reduced, and Figure 1(B) shows an example in which the eye-catching image of a navigation arrow displayed across the first and second display areas, superimposed on the road surface, is reduced.

[0055] 1, the width direction of the vehicle 1 (see FIG. 6(A)) (or the left-right direction, which is the direction along the line connecting a person's left and right eyes) is the X direction, the direction along the perpendicular to the road surface 300 is the up-down direction or height direction, the direction away from the road surface 300 is the up direction, and the direction approaching the road surface 300 is the down direction. In addition, the direction perpendicular to the X and Y directions is the front-rear direction (Z direction), and the direction in which the vehicle 1 moves forward is the forward direction, and the direction in which it moves backward is the backward direction.

[0056] In the example of Fig. 1(A), a virtual display area 100 created by the HUD device 10 in the real space ahead of the vehicle 1 (see Fig. 6(A)) is divided into a first display area 101 and a second display area 102. The first display area 101 is located above the second display area 102.

[0057] In the first display area 100, the eye-catchingness of the image (virtual image) of the display target (display object) is reduced. This prevents the display by the HUD device 10 (see FIG. 6(A)) from interfering with the visual recognition of the background (real scenery) while driving, thereby reducing, for example, annoyance and stress.

[0058] A vehicle (host vehicle) 1 is traveling at a speed of 60 km / h on a road with good visibility. In the real space ahead of the vehicle 1, a virtual display area (in other words, a virtual image display surface) 100 having a rectangular outer shape in a plan view is erected on the road surface (surface corresponding to the ground) 300, and an image (virtual image) of a display object is displayed on this display area (virtual image display surface).

[0059] In the driving scene of FIG. 1(A), a vehicle FC1 traveling ahead and a mountain landscape in the distance are seen as the background (real scene) of the first display area 101. The HUD device 10 displays an image (virtual image) CU1 of a warning mark superimposed on the vehicle FC1 in the first display area 101, and also displays images (virtual images) NV10 and NV20 of navigation arrows that appear to be floating in the air. The HUD device 10 also displays an image (virtual image) NV30 of a destination display (destination display) superimposed on the distant mountains. Note that, although CU1(V1) is displayed in the figure, this (V1) indicates the first virtual image displayed in the first display area 101.

[0060] 1(A), a vehicle speed display SP of "60 km / h" is displayed in the foreground of the second display area 102. In the drawing, SP(V2) is written, and (V2) indicates a second virtual image displayed in the second display area 102.

[0061] 1(A), a vehicle FC2 (located closer to the driver than vehicle FC1) traveling ahead is shown by a dashed line as an actual scene (background) overlapping the second display area 102. This vehicle FC2 does not exist in an actual driving scene, but is shown as a comparative example for the purpose of explaining the process of reducing the visibility of a display object, and is therefore virtual, and is therefore shown by a dashed line.

[0062] Here, the first display area 101 is an area in which images (virtual images) that are thought to be often superimposed (overlaid) on a relatively distant real scene are arranged in the virtual display area 100 of the HUD device 10. In the example of FIG. 1(A), a virtual image CU1 of an attention calling mark, two virtual images NV10 and NV20 of arrows, and a virtual image NV30 of a destination display are superimposed on a vehicle FC2 traveling relatively far away. Here, the attention calling mark, the arrow, and the destination display are each referred to as a display target or a display object.

[0063] In the example of Figure 1(A), there are a large number of display objects. If the images (virtual images) representing these display objects are in colors close to primary colors, are highly bright, or are large in size, the display objects themselves may be so conspicuous that they excessively attract the attention of the viewer (driver), obstructing the view of the background, diverting attention from the background, or creating a sense of incongruity between the display objects and the background, which may cause stress.

[0064] When driving a vehicle, it is said that it is important to maintain a wide field of vision by looking into the distance while also keeping an eye on what is close and your surroundings. However, when driving for long periods of time in particular, you will be paying attention to what is far away for a long time, so visibility of the actual distant scenery (foreground) is an important factor for safe driving.

[0065] In consideration of this point, in Fig. 1(A), the visual appeal of each of the images (virtual images) CU1, NV10, NV20, and NV30 is reduced in the first display area 101 to avoid obstructing the view of the background, excessively drawing the viewer's attention to the background, or creating a sense of incongruity with the background and causing stress, thereby ensuring a comfortable driving experience. The first display area 101 indicates the range in which the visual appeal of the images (virtual images) is reduced. The settings of the first and second display areas 101 and 102 will be described later.

[0066] Here, reducing the conspicuousness of the first virtual image CU2 superimposed on the vehicle FC1 will be described in comparison with the second virtual image CU2 superimposed on the vehicle FC2. Reference is now made to Fig. 2, which is a diagram showing an example of reducing the conspicuousness of a display object (virtual image).

[0067] 2, it is assumed that vehicles FC1 and FC2 are both red. Since vehicle FC2 located closer to the driver is determined to be more dangerous, it is preferable to display the attention-calling mark (second virtual image) CU2 with enhanced visibility. For example, by using blue or green (opposite colors including complementary colors, etc.), the color contrast can be improved, and the visibility can be improved by processing (referred to as process S1) such as making the exclamation mark stand out, maximizing its brightness, or increasing its size.

[0068] On the other hand, the attention drawing mark (first virtual image) CU1 superimposed on the vehicle FC1 located further away is made less conspicuous so as not to obstruct the visibility of the vehicle FC1, which is the actual scene. However, if the visibility is too low and it becomes difficult to see, there is no point in displaying it, so a certain degree of visibility must be ensured.

[0069] Therefore, as an example, by using blue or green (opposite colors including complementary colors, etc.), color contrast is improved and a certain degree of visibility of the attention-attracting mark (first virtual image) CU1 is ensured. On the other hand, for example, the exclamation mark, which is useful for attracting attention but gives a visually complex impression, may be deleted (changing the appearance by not displaying it), or the brightness may be reduced, or the size may be reduced, thereby reducing the overall visibility of the display object. This makes it possible to realize a display that is visible but does not excessively draw attention and causes little stress to the viewer. Note that the above-mentioned methods are merely examples and are not limiting.

[0070] More specifically, reducing the conspicuousness of a display object may be achieved by, for example, at least one of lowering the brightness, reducing the size, lowering the contrast (including color contrast and brightness contrast), changing the color from a primary color to a pale color, slowing down the blinking rate or not blinking at all in a blinking state, shortening the display duration with respect to the period during which the same display object is displayed, slowing down the speed, reducing the cycle, or turning into a still image with respect to the display of moving images, hiding or reducing the size of a highly noticeable part of the display object, and changing the appearance of the display object.

[0071] In addition, in one preferred example, reducing the conspicuousness of a display object may be achieved by suppressing a decrease in visibility by changing the color of the display object to an opposite color, including a complementary color, of the color of the real scene on which the display object is superimposed, while at the same time implementing at least one of lowering brightness, reducing size, hiding or reducing highly noticeable parts of the display object, and changing the appearance of the display object.

[0072] A preferred example of adjusting eye-catchingness is to set the color of the displayed object to a color opposite to, or including a complementary color, the color of the actual background, maintaining a relatively high contrast and ensuring a certain degree of visibility of the image (virtual image) displayed by the HUD device.If the display itself becomes invisible or difficult to see, the purpose of displaying a virtual image is lost, so the visibility of the image (virtual image) is ensured to a certain degree by visual contrast.

[0073] Furthermore, for example, if the actual scene is a dark color close to a primary color, the image (virtual image) will be difficult to see, but if it is an opposing color including a complementary color, the contrast will be high and the image (virtual image) will still be visible. Furthermore, if the viewer looks away from the actual scene, a complementary color afterimage will appear, but if the image (virtual image) is a complementary color, even if a complementary color afterimage appears, it will not feel particularly strange because it is the same color, and in this respect too, the effect of reducing visual stress can be expected.

[0074] On the other hand, by implementing at least one of the following measures, it is possible to effectively reduce the overall visibility of the display object and avoid interfering with the visibility of the background (real scenery). For example, by lowering the brightness, reducing the size, hiding or reducing the size of the highly visible parts of the display object, or changing the appearance of the display object.

[0075] The explanation will be continued by returning to Fig. 1. Referring to Fig. 1(B), in the example of Fig. 1(B), a virtual image 71 of a navigation arrow, which is a display object, is displayed across the first display area 101 and the second display area 102. In this case, the overall conspicuousness of the virtual image 71 of the arrow is reduced.

[0076] This arrow virtual image 71 includes a tip portion 71a displayed in the first display area 101 and a base portion 71b displayed in the second display area 102. However, since it is also arranged in the first display area 101, it is preferable to increase the visibility of the relatively distant background (real scene, foreground) to the viewer. Furthermore, if there is a difference in the degree of eye-catchingness between the first and second display areas 100, 101, it may be perceived as unnatural by the viewer, which may increase the visual burden. Therefore, the eye-catchingness is reduced throughout the entire display.

[0077] Next, reference will be made to Fig. 3. Fig. 3(A) is a diagram showing an example in which the visual appeal is changed depending on the position in the vertical direction within the first display area, and Fig. 3(B) is a diagram showing another example.

[0078] In the example of Fig. 3, in the first display area 101, the level of attention is varied depending on the vertical position (the position where the display object is placed), and the attention is lower when the display object is placed at the top than when it is placed at the bottom. As the viewer looks further away, the attention level of the display object itself is reduced, allowing the viewer to clearly see the actual scene in the distance. This is one suitable example for effectively reducing the viewer's stress.

[0079] The change in visual appeal (level of visual appeal) in the vertical direction may be continuous (as in the example of FIG. 3(A)) or may be gradual (as in the example of FIG. 3(B)). In FIG. 3(B), the first display area 101 is divided into three blocks 101-1 to 101-3, and the more upwardly positioned the block, the less visual appeal it has.

[0080] Next, refer to Fig. 4. Fig. 4(A) is a diagram showing an example of the position of the first display area when driving at a standard speed, Fig. 4(B) is a diagram showing an example of moving the first display area downward when driving at a low speed, and Fig. 4(C) is a diagram showing an example of expanding the first display area downward when driving at a low speed.

[0081] When driving at a standard speed, as shown in FIG. 4(A), the first display area 101 is set to the upper side of the display area 100. Since the driver's line of sight tends to move downward when driving at a low speed, the first display area 101 is moved downward in accordance with this in FIG. 4(B). Moreover, in FIG. 4(C), the first display area 101 is widened (expanded) downward. This makes it possible to set the first display area appropriately according to the driving speed.

[0082] Please refer to Figure 5. Figures 5(A) and (B) show an example in which a first display area is set in a part of the upper side of the display area, and Figures 5(C) and (D) show an example in which the first display area is expanded to the right when turning right. In the following description, a partial (local) arc shape that is part of a circle will be referred to as a partial arc.

[0083] When the vehicle is traveling straight ahead, in Fig. 5(A), a first display area 101 is provided at approximately the center of the upper side of the display area 100, partitioned by a boundary line of a partial arc. The first display area 101 is in the shape of a sector (or a partial circle). In Fig. 5(B), a square-shaped first display area 101 is provided at approximately the center of the upper side of the display area 100.

[0084] Now, assuming that the vehicle is turning right, the driver's line of sight will move to the right. Therefore, in FIGS. 5(C) and (D), the first display area 101 in FIGS. 5(A) and (B) is expanded to the right (right side) in accordance with the rightward shift of the line of sight. This allows a virtual image to be displayed that does not interfere with the driver's view of the background, even when turning right. This reduces the driver's visual and psychological burden.

[0085] Next, reference will be made to Fig. 6. Fig. 6(A) is a diagram showing an example of setting the first display area with the height position of the first line of sight set to the midpoint position of the eyebox, and Fig. 6(B) is a diagram showing an example of setting the first display area with the height position of the first line of sight set to the eye height position.

[0086] As shown on the right side of Fig. 6(A), the HUD device 10 includes, for example, a HUD device main body 20 and an I / O interface 30. The HUD device 10 is housed inside the dashboard 5 of the vehicle 1. In the example of Fig. 6(A), a camera 50 that captures an image of the eyes (or pupils) of a viewer (such as a driver) is also disposed inside the dashboard 5 in order to detect the viewpoint (including the eye position and line of sight) of the viewer. Display light 40 is emitted (projected) from the HUD device main body 20 toward the windshield 2, which is a projection target.

[0087] A portion of the display light 40 is reflected by the windshield 2 and directed toward the viewer's (the driver's or other) eye (viewpoint) A, forming an image in front of the vehicle 1, whereby an image (virtual image) is displayed in the display area 100. The display area 100 can also be referred to as a virtual image display surface. This display area (virtual image display surface) 100 is virtually provided in front of the vehicle 1, corresponding to the display area of ​​the display surface of a screen (reference numeral 160 in FIG. 15 ), for example.

[0088] The distance of the display area 100 from the viewpoint 4 (or a reference position equivalent thereto) is set to L1. This L1 is sometimes referred to as the virtual image display distance. The virtual image display distance L1 can be adjusted appropriately, for example, by moving an optical system (for example, a lens or the like arranged in the light projecting unit 155 in FIG. 13 ) arranged inside the HUD device along the optical axis.

[0089] 6(A), the display area 101 is erected at a slight incline (almost perpendicular) with respect to the road surface 300. However, this is just one example, and for example, by inclining the screen 160 in FIG. 13 with respect to the optical axis, the inclination angle of the display area 101 with respect to the road surface 300 can be adjusted appropriately depending on the degree of the inclination.

[0090] The setting of the first display area 101 will be described below. The first display area 101 is a display range corresponding to the range of, for example, 0 to m degrees (m is an integer greater than 0, for example, m=2) of the angle of depression of the viewer's (driver's, etc.) line of sight (which can be expressed, for example, as the angle between the direction of the line of sight when looking down at an object and the horizontal plane at eye height (or a position equivalent thereto)). In this range, the viewer's (person's) line of sight is approximately parallel to the ground or an equivalent surface (such as the road surface, and in the case of a simulation device or a game device, also the floor surface of the installation location), and is presumed to be looking straight ahead (or slightly lowering their eyes) and looking into the distance. Therefore, by ensuring good visibility of the foreground in this state, it is possible to effectively alleviate (reduce) the viewer's psychological burden, etc.

[0091] Here, the direction of the viewer's (driver's) gaze forward at a depression angle of 0 degrees, starting from the viewer's (driver's) "eye position" or "reference position corresponding to the eye position," is defined as the first gaze direction, and the direction of the viewer's gaze at a depression angle of m degrees (m is an integer greater than 0) inclined from the first gaze direction 700 is defined as the second gaze direction.

[0092] 6(A), center position 205 in the height direction of eye box 200 (the height relative to road surface 300 is set to h1) is the "reference position corresponding to the eye position," and gaze direction 700 represented by a line segment extending forward from center position 205 of eye box 200 is the first gaze direction. Also, the gaze direction represented by a line segment tilted by depression angle Ra from first gaze direction 700 is defined as second gaze direction U10.

[0093] 6(A), the center of display area 100 provided in the real space in front is designated as P, and the line of sight indicated by the line segment connecting center position 205 of eyebox 200 and center P of the display area is designated as U20. This line of sight direction U20 is tilted downward from first line of sight direction 700 by angle θv.

[0094] Here, the intersection point Q1 between the second line of sight direction U10 and the display area 100. Using this intersection point Q1 as a reference (boundary), the first display area 100 is divided into a first display area 100 closer to the first line of sight direction 700 and a second display area 102 other than the first display area, thereby allowing the first display area and the second display area to be set.

[0095] The control unit (reference numeral 120 in FIG. 13) of the HUD device 10 performs control to make the visibility of the first display object (virtual image) displayed in the first display area 101 lower than the visibility of the second display object (virtual image) displayed in the second display area 102.

[0096] Next, refer to Figure 6(B). In Figure 6(B), the starting point of first line of sight direction 710 is the position of the actual eyes (viewpoint). With first line of sight direction 710 as the reference, the direction tilted downward by depression angle Ra is second line of sight direction U11. The other configurations are the same as those in Figure 6(A).

[0097] Next, let us refer to Fig. 7. Fig. 7(A) is a diagram showing an example in which the first and second display areas are separated by a boundary line of a partial arc, and Fig. 7(B) is a diagram showing an example in which the first and second display areas are separated by a straight line segment that crosses the display area from left to right.

[0098] 7(A), point Q0 indicating the position of first line of sight direction 700 or 710 is used as a reference, and point Q1 is taken a distance below it corresponding to depression angle Ra in a plan view from the viewer. A circle 800 passing through this point Q1 is drawn, and the area where this circle 800 and display area 100 overlap is defined as first display area 101, and the area below first display area 101 is defined as second display area 102. First display area 101 in FIG. 7(A) has the shape of a partial circle as previously shown in FIG. 5(A).

[0099] In Figure 7(B), point Q0 is used as a reference point, and point Q2 is taken a distance below it corresponding to depression angle Ra in a plan view from the viewer's perspective. A line segment is drawn that passes through point Q2 and crosses rectangular first display area 101 from left to right, with the entire upper area partitioned by this line segment being the first display area, and the area below that being the second display area 102. First display area 101 in Figure 7(B) corresponds to the example in Figure 4(A) above.

[0100] Next, let us refer to Figure 8. Figure 8 is a diagram showing an example in which a rectangular first display area is set in a portion of the upper side of the display area. In Figure 8, a quadrangle (rectangle) with a height of 2Ra and a width of 2Rb is drawn with point Q0 as the reference (center). The coordinates of the four vertices of this quadrangle are (X1, Y1), (X2, Y2), (X3, Y3), and (X4, Y4).

[0101] The area where this rectangle and display area 100 overlap (overlapping area) is defined as first display area 101. A portion of second area 102 is located below first display area 101. Therefore, in the example of FIG. 8, first display area 101 can also be said to be located above second display area 102. First display area 101 in FIG. 8 corresponds to the example of FIG. 5(B) above.

[0102] Next, reference will be made to Fig. 9. Fig. 9(A) is a diagram showing an example in which a first display surface area corresponding to the first display area and a second display surface area corresponding to the second display area are set on the display surface of the image display unit, and Fig. 9(B) is a diagram explaining a process for reducing conspicuousness when an image (real image) of a display object is arranged in each of the first and second display surface areas.

[0103] 9(A) and 9(B), directions corresponding to the X, Y, and Z directions in real space are denoted as X', Y', and Z'. Furthermore, the display area on the display surface PL of the display panel 143, which corresponds to the display area 100 in real space, is denoted as 100', and this display area 100' will be referred to as the display surface area 100'. Similarly, the area corresponding to the first display area 101 will be referred to as the first display surface area 101', and the area corresponding to the second display area 102 will be referred to as the second display surface area 102'.

[0104] The direction corresponding to the first viewpoint direction is indicated as 700' or 710'. The distance on the display surface PL corresponding to the depression angle Ra is indicated as Ra'.

[0105] As shown in Figure 9(A), the display surface PL of the display panel 143 (see Figure 13) has a first display surface area 101' corresponding to the first display area 101 described above, and a second display surface area 102' corresponding to the second display area 102.

[0106] The setting method is the same as the setting example in real space described above. In other words, using point Q0' as a reference, point Q1' is set vertically (in the Y' direction) below it at a distance of Ra', and the display surface area 100' is divided into two by a line segment that passes through Q1' and crosses the display surface area 100' horizontally. The upper area is designated as a first display surface area 101', and the lower area is designated as a second display surface area 102'.

[0107] The control unit (reference numeral 120 in FIG. 13) performs control to reduce the visibility of the display object (real image or image) arranged in the first display surface area 101'.

[0108] In the example of Fig. 9(B), an arrow image NV'(R) and a vehicle speed display SP'(R) are shown as display objects. Note that (R) indicates a real image. Which image is to be placed in the first display surface area 101' can be determined, for example, by comparing the coordinates of each image with the coordinates of the first and second display surface areas 101' and 102'.

[0109] However, this is not limiting. A simpler determination is also possible. For example, the center point of the arrow image NV'(R) is assumed to be Q11', and the center point of the vehicle speed display SP'(R) is assumed to be Q12'. The distances D1 and D2 between each center point Q11', Q12' and point Q0' may be calculated, and D1 and D2 may be compared to place the image with the shorter distance in the first display surface area 101', and the image with the longer distance in the second display surface area 102'. Note that instead of D1 and D2, the vertical distances D3 and D4 from a line segment L10 extending horizontally through point Q0' may be detected.

[0110] Next, reference is made to Fig. 10. Fig. 10(A) to (D) are diagrams showing an example of setting the first and second display areas when the height position of the first line of sight is fixed and the height position of the display areas is changed according to the eye position. In the example of Fig. 10, the extent (size, area) of the first display area can be adaptively adjusted according to the viewer's eye position in the up-down direction (height direction).

[0111] 10(A), in response to a change in the eye position (4a to 4c), for example, a curved mirror (such as a concave mirror, reference numeral 133 in FIG. 13) included in the optical system rotates to automatically adjust so that display light is incident on the eye position. At this time, when the eye position becomes higher (upper), the line of sight (line of sight) changes to look down (the depression angle changes to increase), and the position of display area 100 also moves downward (the position of the upper end of display area 100 becomes H1). When the eye position becomes lower (lower), the line of sight (line of sight) changes to look far ahead (the depression angle changes to decrease), and the position of the display area also moves upward (the position of the upper end of display area 100 becomes H3). When the eye position is intermediate between the upper and lower positions, display area 100 also changes to be positioned intermediate between the above positions (the position of the upper end of display area 100 becomes H2).

[0112] Here, let us consider a case where the height position of the first gaze direction 700 (710) is fixed (here, fixed at the height of the intermediate eye position 4b and does not change). In all of Figures 10(B), (C), and (D), the height position of the first gaze direction 700 (710) is fixed at the intermediate eye position 4b.

[0113] On the other hand, the actual eye position is the intermediate eye position 4b in Fig. 4(B), the lowest eye position 4a in Fig. 4(C), and the highest eye position 4c in Fig. 4(D). As described above, the height direction position (height position) of display area 100 changes depending on the eye position. The position of intersection Q1 between second line of sight direction U12 and display area 100 changes depending on the change in the height position of display area 100, and as a result, first display area 101, which is the range that reduces visual appeal, expands or shrinks, automatically adjusting its size.

[0114] For example, when the eye position is high (FIG. 4(D)), the direction of the line of sight (eye line) decreases and there is a tendency to look at something close, so the first display area 101 related to viewing the actual scene in the distance automatically becomes narrower.

[0115] On the other hand, as the eye position lowers and the line of sight (eye line) direction rises (as in Figures 4(B) and (C)), the viewer will be able to look further into the distance, and the range of the first display area will automatically expand accordingly. In the case of Figure 4(C), it is considered that the viewer will be in a situation where it is easiest to see into the distance. Therefore, in the case of Figure 4(C), the range of first display area 101 will be the largest. In this way, the range (size, area) of first display area 101 is automatically and appropriately adjusted in accordance with the eye position.

[0116] Next, reference is made to Fig. 11. Fig. 11(A) to (D) are diagrams showing other examples of setting the first and second display areas when the height position of the first line of sight direction is fixed and the height position of the display areas is changed depending on the eye position.

[0117] In the example of Fig. 10, the height position of the first gaze direction is fixed, but in the example of Fig. 11, the height of the first gaze direction is moved appropriately to match the actual eye height position. In any of the cases of Fig. 11(A), (B), and (C), the height position of the first gaze direction 700 (710) is adjusted to match the actual eye positions (4b, 4a, 4c).

[0118] In this case, there is a tendency for the position of intersection Q1 between second line of sight direction U30 and display area 100 to fluctuate more greatly. In the example of Fig. 11, the size (area) of first display area 101 changes depending on the eye position, similar to the example of Fig. 10 (an example in which the height position of first line of sight direction 700 (710) is fixed).

[0119] However, in this example, the position of intersection Q1 fluctuates greatly, so for example, as shown in FIG. 11(C), when the eye position becomes high (the eye position is at the highest position 4c) and the line of sight becomes downward, the first display area 101 related to the viewing of the distant actual scene is not set (in other words, the area of ​​the first display area becomes zero).

[0120] 10 and 11, the vertical position (height position) of intersection Q1 between display area 100 and second line of sight is changed by changing the vertical position (height position) of display area 100, or by combining the vertical position (height position) of display area 100 with the vertical position (height position) of the reference position of first line of sight 700 (710), thereby automatically adjusting the area (size) of first display area 101. This allows the size of first display area 101 to be adjusted as desired.

[0121] Next, reference will be made to Fig. 12. Fig. 12(A) to (C) are diagrams showing an example of adjusting the size of the first display area by performing a correction process to prevent the first line of sight from facing upward when the front edge of the vehicle faces upward. Fig. 12 shows an example of a preferable countermeasure when the direction in which the front edge of the vehicle 1 faces is shifted diagonally upward from the standard state.

[0122] The pitching angle of vehicle 1 may change depending on the balance of the occupants of vehicle 1, the balance of luggage, and the like. For example, if the vehicle is a truck and there is a large amount of cargo in the rear bed, the front of the truck may be facing diagonally upward (upward) from the standard state (normal state). In this case, the display area virtually provided in the real space in front of the viewer (driver) also moves upward, which in turn turns the viewer's (driver's) line of sight upward, making it easier to see further away. In this case, it is preferable to widen the first display area to broaden the range in which the distant real scene can be easily seen. However, without any ingenuity, the sizes of first and second display areas 101 and 102 (or the proportions of each area) remain the same, and the entire display area 100 simply moves upward.

[0123] Here, let us refer to Figures 11(A) and (B). Figure 11(A) shows the standard state (pitch angle 0 degrees), and (B) shows a state deviated from the standard state (pitch angle α). The size of the first display area 101 and the size of the second display area 102 are the same.

[0124] Therefore, in Figure 11 (C), even if the front end of the vehicle 1 is facing upward, the first line of sight direction 700 (710), which is the basis for determining the first display area 101, is prevented from shifting upward, and, for example, a depression angle of preferably 0 degrees is maintained.

[0125] In other words, a process (correction process) is performed to correct the upward deviation and suppress fluctuations in the first line of sight direction so that the direction approaches a depression angle of 0 degrees (pitch angle of 0 degrees). In FIG. 12(C), the direction is corrected to the same direction as when the pitch angle is 0 degrees. Note that the degree to which the direction of the front end of the vehicle is diagonally upward can be determined based on, for example, information from a pitch angle sensor or the like provided on the vehicle.

[0126] When the upward shift of the first viewing direction 700 (710) is suppressed (preferably maintained at a depression angle of 0 degrees), the display area 100 moves upward, and therefore the position of the intersection Q1 with the second viewing direction U30 moves relatively downward.

[0127] The position of the intersection Q1 is also an important factor in determining the position of the boundary line between the first and second display areas 101 and 102, so by moving the position of the intersection Q1 downward, the first display area 101 becomes wider, and therefore the range in which the distant actual scenery is easier to see (the range in which conspicuousness is reduced) becomes wider, thereby achieving the effect of maintaining a state in which the viewer (driver) can easily see the actual scenery ahead and around (in other words, maintaining good visibility, etc.).

[0128] Next, reference will be made to Fig. 13. Fig. 13 is a diagram showing an example of the internal configuration of the HUD device. Main body 20 of HUD device 10 has a display control unit (control unit) 120, an image display unit (display unit) 140, a light projecting unit 155, a screen 129, a curved mirror (concave mirror or the like) 133, and a curved mirror actuator 131. Image display unit 140 has an image generating unit 141 and a display panel 143 (having a display surface PL). Eye position information, rotation angle information of curved mirror 133, etc. are supplied to display control unit (control unit) 120 as appropriate.

[0129] Next, reference will be made to Fig. 14. Fig. 14 is a diagram showing an example of the system configuration of a HUD device. The HUD device 10 has an I / O interface 30, a processor (control device) 160, an image processing unit 200, an image display unit 140, and a storage unit 300.

[0130] The I / O interface 30 is connected to a road information database 403, a vehicle position detection unit 405, an outside vehicle sensor 407, a gaze direction detection unit 409, an eye position detection unit 411, a mobile information terminal 413, and a vehicle ECU 415.

[0131] The vehicle ECU 415 is provided with necessary information as needed from a pitch angle sensor 417, a steering angle sensor 419 (required for the processing shown in FIGS. 5(C) and 5(D)), etc. In addition, the I / O interface 420 is connected to an external communication connection device 420.

[0132] Furthermore, storage unit 300 stores (installs) an attractiveness / visibility change module 326. Attractiveness / visibility change module 326 has an application area setting unit for the attractiveness reduction process (attractiveness reduction range determination unit) 327 and an application area setting unit for the attractiveness reduction process (attractiveness reduction mode determination unit) 329. Processor (control device) 160 operates in accordance with application area setting unit for the attractiveness reduction process (attractiveness reduction range determination unit) 327, thereby constructing a first display area setting unit (not shown) as a functional block.

[0133] In addition, the processor (control device) 160 or the image processing unit 140 operates in accordance with the content determination unit for the attention reduction processing (attraction reduction mode determination unit) 329, thereby constructing an attention reduction processing unit (not shown) as a functional block.

[0134] Next, reference will be made to Fig. 15. Fig. 15 is a flowchart showing an example of a procedure for setting the first and second display areas.

[0135] In step S110, information useful for setting the first display area is acquired. For example, information on the rotation angle of a concave mirror (curved mirror) may be acquired (step S111), information on the eye position (eye height) may be acquired (step S112), etc.

[0136] In step S120, the range of the first display area (the area to which the conspicuousness reduction process is applied) is set. This step S120 may include, for example, setting the first display area based on table data in which the angle of the curved mirror and the range of the first display area are associated (step S121).

[0137] It may also include setting an area close to the first line of sight direction based on the eye position as the first display area (step S122) based on the setting positions (design values, default values, etc.) of the first and second display areas and the eye position.

[0138] It may also include setting an area close to the first line of sight direction based on the eye position as the first display area based on the positions of the first and second display areas estimated from the angle of the concave mirror and the eye position (step S123).

[0139] As described above, according to the present invention, for example, when a viewer directs his or her gaze forward as if looking into the distance, the viewer's line of sight is obstructed by an image (virtual image) from a HUD device that is displayed superimposed on the real scene (foreground) ahead, and this can effectively reduce burdens (including psychological burdens) on the viewer, such as reduced visibility of the foreground, visual attention being drawn to the image (virtual image) and reducing the viewer's visual attention to the foreground, or the viewer feeling annoyed by the image (virtual image).

[0140] In the present invention, the term "HUD device" is broadly interpreted and can be interpreted to include game devices and simulation devices. Terms such as "viewer" and "driver" are also broadly interpreted, and the term "vehicle" can be interpreted as a term that broadly means, for example, any vehicle.

[0141] The present invention is not limited to the above-described exemplary embodiments, and those skilled in the art will be able to easily modify the above-described exemplary embodiments to the extent that they fall within the scope of the claims. [Explanation of symbols]

[0142] 1 Vehicle (host vehicle), 2 Windshield, 5 Dashboard, 10 HUD device, 20 Main body of HUD device 10, 30 I / O interface, 100 Display area (virtual display area, virtual image display surface), 101 First display area, 102 Second display area, 120 Display control unit (control unit), 140 Image display unit (display unit), 155 Light projecting unit, 129 Screen 133···curved mirror (concave mirror, etc.), 131···actuator for curved mirror 131, 141···image generation unit 141, 143···display panel 143, 160···processor (control device), 200···image processing unit, 140···image display unit, 300···memory unit, 700, 710···first line of sight direction, U10, U12, U30···second line of sight direction, Q1···intersection of the display area and the second line of sight direction.

Claims

1. an image display unit that displays an image; an optical system that projects light of the image displayed by the image display unit toward a projection target, thereby allowing the viewer to view a virtual image of the image within a virtual display area in a real space in front of the viewer; a control unit that controls display of the image on the image display unit; and a first gaze direction is a gaze direction of the viewer starting from an eye position of the viewer or a reference position corresponding to the eye position and directed forward at a depression angle of 0 degrees; a second line of sight direction is a line of sight direction of the viewer at a depression angle of m degrees (m is an integer greater than 0) inclined from the first line of sight direction; a direction perpendicular to the first line of sight direction and along a line segment connecting the left and right eyes of the viewer is defined as a left-right direction; When a direction along a line segment orthogonal to the first line of sight direction and the left-right direction is defined as a vertical direction or a height direction, a direction away from the ground or a surface equivalent to the ground in the real space is defined as an upward direction, and a direction approaching the ground is defined as a downward direction, The control unit dividing the virtual display area into a first display area closer to the first line of sight and a second display area other than the first display area, based on an intersection point between the virtual display area and the second line of sight; and setting the first display area and the second display area; performing control to make the attractiveness of a first display object displayed in the first display area lower than the attractiveness of a second display object displayed in the second display area; A head-up display device.

2. The first display area and the second display area are: the first display area is separated from the second display area by a line segment that passes through an intersection of the virtual display area and the second line of sight, extends in the left-right direction, and crosses the virtual display area, and the first display area is located above the second display area; Or, the virtual display area is divided by a boundary line formed by a part of a line segment that passes through an intersection of the virtual display area and the second line of sight, extends in the left-right direction, and crosses the virtual display area, and the first display area is located above a part of the second display area; Or, the virtual display area is divided by a boundary line that is a partial arc or a curve that passes through an intersection point between the virtual display area and the second line of sight direction, and the first display area is located above the second display area; 2. The head-up display device according to claim 1, wherein:

3. The control unit Within the first display area, a difference in visibility is provided depending on the position in the up-down direction, and visibility is lower when the display object is arranged at an upper position than when the display object is arranged at a lower position.

3. The head-up display device according to claim 1 or 2.

4. The control unit When a display object is displayed across the first display area and the second display area, the overall conspicuousness of the display object is reduced.

4. The head-up display device according to claim 1, wherein the head-up display device is a head-up display.

5. 5. The head-up display device according to claim 1, wherein the head-up display is mounted on a vehicle.

6. The control unit When the direction in which the front end of the vehicle faces is shifted obliquely upward from a standard state, a correction process is performed to suppress fluctuation of the first line of sight direction in accordance with the shift obliquely upward.

6. The head-up display device according to claim 5,

7. The control unit When the speed of the vehicle is slow, the first display area is moved downward compared to when the speed is fast.

7. The head-up display device according to claim 5 or 6.

8. The control unit When the speed of the vehicle is slow, the first display area is expanded downward compared to when the speed of the vehicle is fast.

7. The head-up display device according to claim 5 or 6.

9. The control unit When the vehicle turns right or left, the first display area is expanded in the left-right direction, and when the vehicle turns right, the first display area is expanded to the right, and when the vehicle turns left, the first display area is expanded to the left.

9. The head-up display device according to claim 5, wherein the head-up display device is a head-up display.

10. the optical system has a curved mirror, and the curved mirror rotates in response to a change in the eye position of the viewer, and the position of the virtual display area in real space changes in the vertical direction accordingly; By changing the virtual display area in the up and down direction, Or, a vertical change in the virtual display area and a vertical change in the reference position of the first line of sight, a vertical position of an intersection between the virtual display area and the second line of sight direction is changed, thereby adjusting the area of ​​the first display area; The head-up display device according to any one of claims 1 to 9,

11. Reducing the visibility of the display object Low brightness, and, Reducing the size, and, Low contrast, and, Changing the color palette from primary to pale colors, and, In the blinking state, slow down the blinking rate or stop blinking; and, shortening the display duration with respect to the period during which the same display object is displayed; and, Regarding the display of moving images, at least one of slowing down the speed, slowing down the cycle, and displaying still images is implemented; and, hiding or reducing a highly visible part of the display object; and, changing the appearance of the display object; This is achieved by at least one of 11. The head-up display device according to claim 1,

12. Reducing the visibility of the display object The color of the display object is set to an opposite color, including a complementary color, of the color of the actual scene on which the display object is superimposed to suppress a decrease in visibility, On the other hand, the effect is realized by performing at least one of lowering brightness, reducing size, hiding or reducing a highly visible part of the display object, and changing the appearance of the display object.

11. The head-up display device according to claim 1,

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