JP2022100119A - Display control device, head-up display device, and image display control method - Google Patents

Abstract

To effectively prevent crosstalk from being easily recognized by a viewer (crosstalk becoming conspicuous) as the perceived distance of a content image increases in a parallax 3D head-up display (HUD) device.SOLUTION: A display control device has a control part 701 for controlling the image display, and the control part 701 performs 3D display processing and perceptual distance changing processing for changing the perceptual distance of a content image. In the perceptual distance changing processing, visibility lowering processing for decreasing the visibility of the content image stepwise or continuously is also executed when the perceptual distance increases.SELECTED DRAWING: Figure 4

Description

The present invention relates to a display control device, a head-up display (HUD) device, an image display control method, and the like mounted on a vehicle such as an automobile.

Patent Document 1 discloses an in-vehicle stereo image display device that displays information such as outside vehicle information and vehicle traveling guidance information as a three-dimensional stereo image (stereoscopic image) by utilizing the principle of stereoscopic vision based on both visual differences. There is. In [0031] of Patent Document 1, as an effect of the invention, "the image can be recognized with a three-dimensional effect and a sense of distance in line with the actual scene seen by the occupant through the windshield, and the occupant can receive information outside the vehicle and guidance information. There is an advantage that it can be given accurately. "

Patent Document 2 shows an example in which a first route guidance content for guiding a vehicle is moved, and then a fourth route guidance content indicating a turning point (direction turning point) in the traveling direction of the vehicle is displayed. ..

Japanese Patent Application Laid-Open No. 7-144578 ([0004], [0031], FIG. 4, etc.) JP-A-2020-64047 ([0165], FIG. 17)

The present inventor uses a parallax-type three-dimensional display as a display, and gives the driver an arbitrary convergence angle to allow the driver to visually recognize a three-dimensional image (three-dimensional image with a sense of depth) (a head-up display device). Here, a parallax type 3DHUD device) was examined. As a result, the following issues became clear.

In the parallax type 3DHUD device, a left viewpoint image (parallax image for the left eye) and a right viewpoint image (parallax image for the right eye) having a parallax are displayed on a virtual first surface (adjustment surface), and typically. A three-dimensional image (three-dimensional image with a sense of depth) is displayed on a second surface (congestion surface) located behind the first surface when viewed from the viewer.

Here, a stereoscopic image (in other words, the above) is based on a reference point on the viewer side (for example, a viewpoint position of the viewer, a specific position on the vehicle, or a predetermined coordinate position in the real space on the viewer side). The distance to the second surface) is referred to as a "perceived distance", which is the distance at which the stereoscopic image is perceived by the viewer.

When the perceived distance becomes long (in other words, the stereoscopic image is displayed farther), the distance between the left / right viewpoint images displayed on the first surface (the amount of displacement of the position of each viewpoint image). ) Increases, and the difference in appearance of each viewpoint image is enlarged. Therefore, in the state where the perceptual distance is long, the viewer is more likely to recognize the crosstalk than in the state where the perception distance is short.

Here, crosstalk will be described. In the disparity type 3DHUD device, an image for the right eye and an image for the left eye are each created by, for example, one display device, and each display light is emitted toward the left eye / right eye. For example, an image for the left eye is displayed. Light may be incident on the right eye and the display light of the image for the right eye may be incident on the left eye (reverse vision), or the display light of the two viewpoint images may be incident on either eye at the same time (reverse view). Image mixing) is also available. When the display light of the other viewpoint image is incident on an eye that should not be incident, stereoscopic viewing is not possible and a strange ghost image is visible to the viewer. This is a phenomenon called crosstalk. The occurrence of crosstalk can also be a factor in eye fatigue and distraction of the viewer (driver) while driving.

This crosstalk occurs at the same frequency regardless of the length of the perceived distance of the content image, but the discomfort given to the viewer when the crosstalk occurs becomes stronger as the perceived distance increases.

In other words, when reverse vision or image mixing occurs in an image having a large difference in appearance, the distortion of the ghost image increases, which results in an increase in discomfort. Therefore, it is preferable to take appropriate crosstalk measures based on the finding that the sense of discomfort differs depending on the perceived distance.

Further, as the content image, for example, an augmented reality element for guiding the course of the vehicle (for example, a graphic element of an arrow as an AR display) is made to overlap the road surface or away from the road surface and along the road surface. It may move by changing its position at any time. When displaying moving augmented reality elements, it is undeniable that it is difficult to accurately distribute the display light to each of the left and right eyes, and crosstalk is likely to occur, so an appropriate cross based on the above findings. It is preferable that measures against talk are taken.

In addition, for example, the figure of the arrow for guiding the course of the vehicle may move on the road surface, and then the figure may be switched to the figure of the arrow for turning to indicate the turning point (for example, the point of turning right or left). It can be assumed.

In this case, it is considered that the figure of the arrow for changing the direction is often displayed in a stationary state or a state with little movement in the vicinity of a certain point. Therefore, even when the above-mentioned crosstalk countermeasures are taken, the nature of the content image to be displayed (for example, whether the content image is moving, has little movement, or is a stationary content image, etc.) is determined. In consideration, it is also necessary to flexibly change the processing content.

The present inventor has clarified such a problem. The above-mentioned Patent Documents 1 and 2 do not mention this problem or its solution at all.

One of the objects of the present invention is to make it easier for the viewer to recognize the cross talk as the perceptual distance of the content image increases in the parallax type 3D head-up display (HUD) device (so that the cross talk becomes conspicuous). To be effectively prevented.

Other objects of the invention will be apparent to those skilled in the art by reference to the embodiments exemplified below and the best embodiments, as well as the accompanying drawings.

Hereinafter, in order to easily understand the outline of the present invention, embodiments according to the present invention will be illustrated.
In the first aspect of the present invention, the display control device is
A display control device that executes display control in a head-up display device that causes a viewer to visually recognize the image by projecting an image onto a projected member.
With one or more processors
With memory
It comprises one or more computer programs stored in the memory and configured to be executed by the one or more processors.
The processor functions as a control unit that controls image display by operating based on the computer program.
The control unit
A 3D display process for displaying a three-dimensional content image with a sense of depth by visually recognizing a left-viewpoint image and a right-viewpoint image having parallax to the left and right eyes of the viewer.
The perceptual distance changing process of changing the perceived distance, which is the distance perceived by the viewer, is executed.
The perceptual distance changing process includes a visibility reducing process that gradually or continuously reduces the visibility of the content image when the perceptual distance increases.

In the first aspect, as the perceived distance increases (in other words, as the display position of the image becomes far away), the visibility of the image decreases. As a result, the visibility of the ghost image due to crosstalk is also reduced, so that it is difficult for the viewer to recognize the crosstalk. Therefore, for example, a feeling of strangeness is reduced. Reducing discomfort also contributes to safe driving.

In the second aspect, which is subordinate to the first aspect,
The visibility reduction process is
Of the content image
Processing to reduce brightness (brightness),
as well as,
Processing to bring the hue closer to blue,
as well as,
Processing to reduce saturation,
May contain at least one of.

In the second aspect, at least one of reducing the brightness (luminance), bringing the hue closer to blue, and lowering the saturation is carried out as a means for reducing the visibility of the image. For example, in the L ^* a ^* b ^* color space or the L ^* c ^* h ^* color space, crosstalk is recognized by appropriately changing the above three elements and performing appropriate change control of visibility. It is possible to realize a difficult 3D display.

For example, if the brightness (brightness) of the image is lowered, the brightness of the crosstalk image is also lowered, and it becomes difficult for the viewer to recognize the crosstalk. Specifically, for example, the display luminance of the content having a parallax angle difference of 0 ° is set as the maximum luminance, and the display luminance is lowered as the parallax angle difference increases.

The "parallax angle difference" is the difference between the "convergence angle (β) of the distant stereoscopic image" and the "convergence angle (α) of the left and right viewpoint images on the front side" as the "parallax angle difference (α-). It is called β) ”.

A parallax angle difference of 0 ° means that a 2D image without parallax is displayed on the display surface of the left and right viewpoint images (referred to as the "first display surface") (the same image is displayed for each of the left and right eyes). It is in the state of being visually recognized). In the case of 2D display, the image is located on the first display surface, but when the parallax angle difference becomes larger than 0 °, a stereoscopic image by 3D representation is placed deeper (farther) with respect to the first display surface. The image is displayed.

When the display surface (congestion surface) of a stereoscopic image is the "second display surface", the distance between the "first display surface" and the "second display surface" is the "virtual distance (or depth distance)". The distance from the reference point on the viewer side (for example, the viewpoint of the viewer) to the second display surface is the above-mentioned "perceived distance (or 3D display distance)". As the virtual distance increases, a process of reducing the brightness (brightness) of the left and right viewpoint images displayed on the first surface is executed by, for example, a processor (control unit). It should be noted that the decrease in brightness (brightness) can be rephrased as "decrease in gradation", and can also be rephrased as "the tint approaches black".

Further, it is possible to reduce the visibility by shifting the color of the left and right viewpoint images toward the blue direction as the display position of the stereoscopic image by 3D representation shifts farther. In other words, by shifting the color scheme of the image toward the blue direction, which is said to have low human sensitivity, it is possible to make the display difficult to recognize crosstalk without changing the dimming parameters.

Also, due to the aerial perspective, distant objects tend to be more bluish and visible than similar objects placed nearby. Therefore, even when the color is changed in the blue direction, the expression is close to the actual landscape (distant view), and it is considered that the viewer does not feel uncomfortable with the displayed content, and no particular problem occurs.

When the initial value of the display content is the maximum value (MAX) of blue, it is not possible to shift to the blue direction, but even in this case, for example, the brightness (luminance) is lowered to change the color to black. It is possible to bring them closer and change the visibility. In addition, the visibility can be changed by reducing the saturation.

In addition, the saturation can be adjusted independently to change the visibility. For example, when a 3D representation stereoscopic image is in the vicinity, it is made a vivid color close to the primary color, and as it is far away, it is changed to a dull color, and finally it is made an achromatic color to control visibility. It is possible to do.

In the third aspect, which is subordinate to the first or second aspect,
The visibility reduction process is
The outline of the content image may be blurred stepwisely or continuously, and a blurring process may be included.

In the third aspect, by blurring the outline of the content image, the boundary between the crosstalk image (ghost image) and the original display image is blurred, and it is possible to provide a display in which crosstalk is difficult to recognize.

The blurring of the displayed image itself has some influence on the viewer. However, since the contour of the human eye looks hazy due to the aerial perspective as the display is farther away, even if the display image is blurred by the above processing, there is little discomfort with the content image, and there is no particular problem.

In the fourth aspect, which is subordinate to any one of the first to third aspects,
The control unit
Regarding the first content image as the content image, the perceived distance is increased to the first perceived distance by the perceived distance changing process, and accordingly, the visibility of the first content image is increased by the visibility decreasing process. Is reduced, thereby putting the first content image in a hidden state or a state close to it.
The first content has visible visibility at the first perceptual distance or a second perceptual distance near the first perceptual distance during the perceptual distance change process or after the perceptual distance change process. A second content image as the content image, which has a different display mode from the image, may be displayed.

In the fourth aspect, when the first content image is subjected to the visibility reduction process due to the increase in the perceptual distance, and the process of switching from the first content image to the second content having a different display mode is executed. An example of a preferable display processing of the above is exemplified.

With respect to the first content image, the visibility becomes extremely low (hidden or close to it) as the perceived distance increases.

On the other hand, with respect to the second content image, the first perceived distance of the first content image is in the middle of the continuous increase of the perceived distance of the first content image or after the increase of the perceived distance is completed. It is displayed at the same or near a second perceptual distance as, and with visible visibility.

This makes it possible to smoothly switch content images with less discomfort. In other words, at the timing when the second content image is displayed, the visibility of the first content image is considerably reduced, so that the two content images coexist (the state in which the two images are clearly visible). This causes confusion) is prevented, and therefore visual annoyance is suppressed.

Further, unlike the first content image, which is in a state close to non-display, the second content image is displayed with visible visibility, and this visual change (difference in visibility) occurs. It creates an attractiveness, and the viewer is attracted to the second content image, and thus surely visually recognizes the second content image. As a result, the information contained in the second content image is surely transmitted to the viewer.

In the fifth aspect, which is subordinate to the fourth aspect,
The first content image is an augmented reality element indicating a moving object whose position is changed at any time.
The second content image may be an augmented reality element having a function as a mark, a guide display, or a road sign, which is superimposed on a specific point or a real scene in the vicinity of the point.

In the fifth aspect, preferable examples of the first and second content images are illustrated. The first content image may be a moving augmented reality (AR) element, and the second content image is an augmented reality (AR) element having the functions of a point marker, a guide display, and a road sign. May be good. Specifically, the first content image may be a graphic element of an arrow that guides the course of a person. In addition, the second content image may be a guidance display (or a mark display) that prompts a person to turn right or left at a turning point, and is a road sign that prompts an action such as "pause, left / right confirmation". You may.

In the sixth aspect, which is subordinate to the fourth aspect,
The first content image is an augmented reality element that moves along the road surface in order to guide the traveling of the vehicle on which the viewer is on board.
The second content image may be an augmented reality element having a function as a mark, a guide display, or a road sign regarding the operation of the vehicle, which is superimposed on a specific point or a real scene in the vicinity of the point. ..

The sixth aspect shows preferable examples of the first and second content images on the premise that the display control device is mounted on the vehicle.

The first content image (for example, a moving AR element) is, for example, a graphic element of an arrow for guiding the course of a vehicle. The graphic element of this arrow may move, for example, so as to overlap the road surface or away from the road surface and change its position at any time along the road surface. When displaying such a moving AR element, it is undeniable that it is difficult to accurately distribute the display light to each of the left and right eyes, and crosstalk is likely to occur, so that visibility is accompanied by an increase in perceptual distance. It is preferable to carry out the reduction treatment.

Further, as the second content image, for example, a graphic element (AR element) of an arrow for turning direction indicating a turning point (for example, a point of turning right or a left turn) can be mentioned. As the driving scenes to which the first and second content images are related, for example, the following can be considered. For example, the graphic element of the arrow for guiding the course of the vehicle (first content image) moves on the road surface, and then the graphic of the arrow for turning indicating the turning point (for example, the point of turning right or left). It is a driving scene that switches to an element (second content image).

In this case, it is considered that the graphic element (second content image) of the arrow for turning is often displayed in a stationary state or a state with little movement in the vicinity of a certain point. Therefore, for the second content image, it is more important for the viewer to clearly see (confirm) the point of right turn or left turn than to take measures against crosstalk due to the deterioration of visibility. Give and display.

In this way, the processing content can be flexibly changed in consideration of the nature of the content image to be displayed (for example, whether it is a moving content image, little movement, or a stationary content image). By doing so, it is possible to achieve both measures against crosstalk and ensuring the necessary visibility.

The graphic element of the arrow for changing the direction (example of the second content image) is considered to be a kind of guidance display. As another specific example, a road sign such as "display of a mark indicating the position of the destination" or "pause, driving, left / right confirmation" can be given. When displaying these as the second content image, it is prioritized to make the viewer surely see (confirm) as in the above example (example of the arrow element for changing the direction). Therefore, it is preferable to perform the same processing as in the above example. The meanings of the landmarks, guide signs, and road signs shall be interpreted flexibly in a broad sense. For example, the guidance display may include advertisements and signboards.

In the seventh aspect, which is subordinate to any one of the fourth to sixth aspects,
The adjustment distance is defined as the distance from the reference point set on the viewer side to the display position of the left viewpoint image and the right viewpoint image having the parallax.
The distance from the display position of the left viewpoint image and the right viewpoint image having the parallax to the position where the first content image or the second content image is perceived is the first virtual distance or the second virtual distance. As a distance
When the distance obtained by adding the first virtual distance to the adjusted distance is defined as the first perceived distance, and the distance obtained by adding the second virtual distance to the adjusted distance is defined as the second perceived distance.
The control unit
After starting the display of the second content image, the second virtual distance may be maintained for a period in which the 3D display is possible.

In the seventh aspect, regarding the display of the second content image, even if time elapses from the display start time, the second virtual distance (the display position of the left viewpoint image having the parallax and the right viewpoint image (first). The distance from the display surface) to the position where the second content image is perceived (second display surface) is maintained as much as possible.

The viewer perceives the stereoscopic image at a position behind the display position (first surface) of the viewpoint image (parallax image) for each eye by a virtual distance. Therefore, if the second virtual distance is shortened or the like, a sense of incongruity may occur. Therefore, it was decided to maintain the second virtual distance as much as possible.

In the eighth aspect, which is subordinate to the seventh aspect,
The control unit
When the second perceived distance of the second content image is shortened, the second perceived distance is shortened while maintaining the second virtual distance, but the visibility of the second content image is lowered regardless of the shortening. You may not let it.

In the eighth aspect, when the perceived distance of the second content image is shortened, for example, by the vehicle approaching the turning point, the second virtual distance is shortened while maintaining the second virtual distance as described in the seventh aspect. However, in this case, the visibility of the second content image is not reduced, but at least maintained, regardless of the shortening of the perceived distance.

As described above, it is important to make sure that the viewer can see (confirm) the second content image. Therefore, priority is given to visibility over crosstalk countermeasures, and visibility reduction processing is not performed. ..

In the ninth aspect, which is subordinate to any one of the fourth to eighth aspects,
The control unit
At the start of displaying the second content image, the visibility may be lowered for a certain period of time and then lowered.

According to the ninth aspect, control is performed in which the visibility is temporarily increased and then decreased at the display start time of the second content image. This makes it possible to enhance the attractiveness of the second content image. Therefore, the viewer can reliably see the newly displayed second content image without overlooking it.

In the tenth aspect, which is subordinate to the ninth aspect,
The control unit
As the second perceptual distance is shortened, the visibility of the second content image may be increased.

In the tenth aspect, after the visibility control of the ninth aspect, the perceived distance (second perceived distance) of the second content image is further shortened (for example, the vehicle approaches the turning point). Correspondingly, the second perceived distance is gradually shortened), and the visibility is increased according to the shortening of the distance. In other words, as the viewer and the position of the second content image get closer to each other, the visibility of the second content image is improved and the attractiveness of the second content image is increased. This ensures that the viewer does not overlook the second content image. Therefore, for example, a driving error such as a vehicle inadvertently passing a turning point can be suppressed.

In the eleventh aspect subordinate to any one of the fourth to tenth aspects,
The control unit
The visibility of the second content image is set lower than the visibility of an image that is located closer to the second content image and is not intended to be superimposed on the actual scene when viewed from the viewer. You may.

In the eleventh aspect, the visibility of the second content image is an image displayed on the front side when viewed from the viewer and not intended to be superimposed on the actual scene (background) (image of non-superimposed content: for example, vehicle speed display). Set lower than the visibility of.

The vehicle speed display, the display of the instrument of the vehicle, etc. are clearly displayed on the front side when viewed from the viewer (driver, etc.). Here, if the second content image displayed in the distance has the same visibility as the vehicle speed display or the like, the viewer will have two displays that are attracted, which is annoying. May be done. In consideration of this point, it is preferable that the visibility of the second content image in the distance is set lower than the visibility of the vehicle speed display on the front side.

Also, considering that the distant real scene looks hazy due to the aerial perspective, reducing the visibility of the second distant content image is consistent with the actual appearance of the distant scene, which is a particular problem. Does not occur.

In the twelfth aspect, which is subordinate to any one of the first to eleventh aspects,
The control unit
When displaying the content image on the front side of the positions of the left viewpoint image and the right viewpoint image having the parallax when viewed from the viewer, the content image is displayed.
The visibility of the content image may be the same as or close to the visibility when the 2D display is performed with the parallax angle difference as 0 °.

In the twelfth aspect, when the second content image appears to protrude from the position of the left viewpoint image and the right viewpoint image having parallax (in other words, the first surface) to the viewer, the second content image appears to protrude toward the front side. The visibility is the same as or close to the visibility when the parallax angle difference is set to 0 ° and the display is 2D (for example, the display brightness is equivalent).

When the visibility (for example, the display brightness) is lowered, it becomes difficult for the viewer (driver or the like) to recognize that the second content image is projected toward the front side. In other words, it causes a situation in which the viewer's perception of distance is reduced. Therefore, in order to prevent this, the visibility (for example, display brightness) of the content image that pops out to the front when viewed from the viewer is not positively changed, and the visibility is the same as or close to the visibility of the 2D display. Be sex.

In the thirteenth aspect, the head-up display device is
A head-up display device that allows a viewer to visually recognize an image by projecting an image onto a projected member.
An image generation unit that generates the image and
A display unit that displays the image and
An optical system including an optical member that reflects the display light of the image and projects it onto the projected member.
The display control device according to any one of the first to twelfth aspects, and
Have.

According to the thirteenth aspect, it is possible to effectively prevent the viewer from easily recognizing the cross talk (the cross talk becomes conspicuous) as the perceived distance of the content image increases. , A parallax type 3D head-up display (HUD) device can be provided.

In the fourteenth aspect, the image display control method is
It is an image display control method.
The first step of determining the perceived distance, which is the distance perceived by the viewer of the content image,
A second step of performing a 3D display process of displaying a left-viewpoint image and a right-viewpoint image having parallax as a content image with a depth expression added to the left and right eyes of the viewer.
When the perceptual distance change process for changing the perceptual distance is performed, when the perceptual distance increases, the content image is visually recognized by adjusting at least one of the brightness, hue, and saturation of the content image. A third step of performing a visibility reduction treatment for gradually or continuously reducing the property, and a third step.
including.

According to the fourteenth aspect, it is possible to effectively prevent the viewer from easily recognizing the crosstalk (the crosstalk becomes conspicuous) as the perceived distance of the content image increases. , An image display control method can be provided.

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

FIG. 1A is a diagram showing an example of the configuration of an in-vehicle system including a parallax type 3DHUD device, and FIG. 1B is a diagram showing an example of a 2D display having no parallax angle difference. FIG. 2A is a diagram showing a region and the like capable of 3D display by an in-vehicle HUD device, and FIG. 2B is a diagram showing an example of 3D display in a driving scene. 3 (A) to 3 (E) show changes in the positions of the left and right viewpoint images having parallax and the stereoscopic image having a sense of depth displayed in the distance with respect to the parallax angle difference in the parallax type 3D display. It is a figure which shows. 4 (A) to 4 (E) are diagrams showing an example of a case where a process of reducing visibility corresponding to a perceived distance is performed as a measure against crosstalk. 5 (A) and 5 (B) are diagrams illustrating control of visibility using the L ^* a ^* b ^* color space. FIG. 6 is a diagram illustrating control of visibility using an L ^* c ^* h ^* color space. 7 (A) to 7 (D) are diagrams showing display examples using the first and second content images in the driving scene. 8 (A) to 8 (H) are diagrams showing a control example of visibility and virtual distance in the display example of FIG. 7. FIG. 9A is a diagram showing an overall configuration example of a parallax type 3DHUD device capable of controlling a change in visibility as a measure against crosstalk, and FIG. 9B is a diagram showing a configuration example of a control unit and an image generation unit. Is. FIG. 10 is a flowchart showing an example of an image display control procedure.

The best embodiments described below have been used to facilitate understanding of the present invention. Accordingly, one of ordinary skill in the art should note that the invention is not unreasonably limited by the embodiments described below.

(First Embodiment)
See FIG. FIG. 1A is a diagram showing an example of the configuration of an in-vehicle system including a parallax type 3DHUD device, and FIG. 1B is a diagram showing an example of a 2D display having no parallax angle difference.

In FIGS. 1A and 1B, the direction along the line connecting the left and right eyes E1 and E2 of the viewer (in other words, the width direction of the vehicle 1) is defined as the left-right direction (or the lateral direction: X direction). , The direction along the line segment orthogonal to the ground or the surface corresponding to the ground (here, the road surface 6) is defined as the vertical direction (or the height direction: Y direction), and the horizontal direction and the vertical direction. The direction along the line segment orthogonal to each of the above (direction indicating the forward and backward directions of the vehicle 1) is defined as the front-rear direction (Z direction). The positive Z direction is the front and the negative Z direction is the rear. This point is the same in other drawings (FIGS. 2 and 7).

The in-vehicle system provided in the vehicle (own vehicle) 1 of FIG. 1A is for detecting the pupil (or face) that detects the line-of-sight direction and position of the left eye EL and the right eye ER of the driver (viewer or observer). The pupil detection camera 43, the front (broadly speaking, surrounding) image pickup camera (for example, a stereo camera) 45, the image processing unit 46 (including the ranging unit 47, the object type / size detection unit 48), and the HUD device 100. , A communication unit (having functions such as GPS communication and inter-vehicle communication) 123, and an ECU 120 capable of collecting various information related to the vehicle 1 (for example, lighting on / off information, vehicle speed information, engine information, etc.). If necessary, a radar unit 125 or the like may be further provided as a distance measuring means. The distance measuring means can be used, for example, to measure the distance from the own vehicle to the vehicle in front (the object ahead). Based on this measurement result, display control is performed, for example, parallax type 3D display is performed in a range where there is no object on the other side.

The parallax unit 47 included in the image processing unit 46 refers to, for example, a pair of left and right original images captured by a stereo camera as an image pickup camera 45, and is the same by, for example, stereo matching for searching for a corresponding point of each image. Parallax with respect to an object (referred to as the destination object) is detected, and the distance measurement to the destination object is measured by the principle of triangulation based on this parallax. Further, the radar unit 125 measures the distance and direction to the object (destination object) by emitting radio waves toward the object (destination object) and measuring the reflected wave. The information acquisition unit 119 of the HUD device 100 appropriately acquires the measured distance information and the like, and supplies the measured distance information and the like to the control unit 701 of the stereoscopic display device 111.

The HUD device 100 is installed, for example, in a dashboard (not shown in FIG. 1, reference numeral 41 in FIG. 2B). The HUD device 100 includes a stereoscopic display device 111, an optical system 116, a light emitting window 118, and an information acquisition unit 119. The information acquisition unit 119 can acquire various information from the communication unit 127, the ECU 120, the radar unit 125, the image processing unit 46, and the like.

The stereoscopic display device 111 is a parallax type 3D display device here. The stereoscopic display device (differential 3D display device) 111 includes an image generation unit 112, an image display unit (a liquid crystal display device or the like, which has an image display surface for displaying an image) 113, a lenticular lens, and a paralux barrier. It has (parallax barrier) and the like, and has a light ray separating unit 114 and a control unit 701 that separate light emitted from an image display surface into light rays for each of the left and right eyes.

The control unit 701 can control the operation of, for example, an image generation unit (specifically, image rendering) 112 and an image display unit 113, and can switch between 2D display and 3D display, and can crosstalk. Visibility control of the content image as a countermeasure can also be performed. Further, the control unit 701 may be provided as a component of the display control device (not shown in FIG. 1A, reference numeral 700 in FIG. 9A).

The optical system 116 has a curved mirror (concave mirror or the like) 117 that reflects the light from the light ray separating unit 114 and projects the display lights K1 and K2 of the image onto the windshield (projected member) 2. However, other optical members (lens, auxiliary reflector, etc.) may be further provided.

In FIG. 1A, the stereoscopic display device 111 of the HUD device 100 displays a viewpoint image having parallax (sometimes referred to as a “parallax image”) for each of the left and right eyes. As shown in FIG. 1A, each parallax image is displayed as an image (virtual image) 25L, 25R formed on the adjustment surface (image plane) PS.

In the following description, the "adjustment plane (image plane) PS" may be referred to as the "first plane". The stereoscopic image (stereoscopic image, 3D image) 27 having a sense of depth may be a congested surface VS (this may be referred to as a "second surface") located on the back side of the first surface PS when viewed from the viewer. ) Is displayed.

Further, the position of the adjustment surface (first surface) PS may be referred to as an "adjustment position". Further, the adjustment surface (for example, the viewpoint position of the viewer, a specific position on the vehicle, a predetermined coordinate position in the real space of the viewer, etc.) set on the viewer side is used as a reference. The distance to the surface (1st surface) (reference numeral D100 in FIG. 2) is referred to as an adjustment distance, and the distance to the congestion surface (second surface) VS (reference numeral D300 in FIG. 2A) is determined by the viewer. It may be referred to as "perceived distance (or congestion distance)" which is the perceived distance.

Further, the distance (reference numeral D200 in FIG. 2) from the adjustment surface (first surface) to the congestion surface (second surface) is referred to as a virtual distance (or depth distance). The perceived distance (reference numeral D300 in FIG. 2A) can also be said to be a distance obtained by adding a virtual distance (reference numeral D200 in FIG. 2A) to the adjustment distance (reference numeral D100 in FIG. 2A). ..

When the 2D display control is executed, a planar virtual image 29 (a figure of an arrow for navigation) is displayed on the adjustment surface (image plane) PS as shown in FIG. 1 (B). A planar virtual image may be referred to as a "2D image or a 2D virtual image" or the like.

Next, refer to FIG. FIG. 2A is a diagram showing a region and the like capable of 3D display by an in-vehicle HUD device, and FIG. 2B is a diagram showing an example of 3D display in a driving scene.

In FIG. 2A, the parallax type 3DHUD device is mounted on the vehicle 1, projects an image (display light) on the windshield 2, and displays an image (virtual image) in front of the viewer (driver). do.

In FIG. 2A, the region indicated by reference numeral 21 (the region with a sand pattern) is a region capable of parallax-type 3D display (parallax-type 3D displayable region). The 3D image can also be displayed on the front side when viewed from the viewer, rather than the adjustment surface (first surface) PS. In the example of FIG. 2A, the congestion surface (second surface) VS is set to the back side of the adjustment surface (first surface) PS. As described above, reference numeral D100 indicates an adjustment distance (imaging distance), reference numeral D200 indicates a virtual distance (depth distance), and reference numeral D300 indicates a perceived distance (3D display distance).

Specifically, the adjustment surface (first surface PS) is set at a distance of, for example, 5 m to 8 m from the reference point (reference position) on the viewer side. However, this is an example, and the present invention is not limited to this.

See FIG. 2 (B). In FIG. 2B, the vehicle 1 is traveling on a straight road (road surface) 6. In the example of FIG. 2B, the viewer 5 is the driver of the vehicle 1. The HUD device 100 is installed in the dashboard 41. The HUD device 100 projects an image (display light) on the windshield 2. Further, the display area (HUD display area) 3 is a virtual area corresponding to the adjustment surface (first surface) PS.

Further, in the display example of FIG. 2B, for route guidance as a three-dimensional virtual image so as to be superimposed on the road surface (surface corresponding to the ground) 6 (or in a state of floating away from the road surface). The figure element FU of the arrow of is displayed.

The graphic element FU of this arrow is a kind of augmented reality (AR) element, and in the example of FIG. 2B, it can move in front of the vehicle 1 to indicate the course of the vehicle 1. In other words, the distance between the vehicle 1 (or the viewer 5) and the graphic element FU of the arrow is variable, and the graphic element FU of the arrow apparently moves faster than the vehicle 1 to the vehicle 1. The distance to the vehicle 1 can be increased, or the distance to the vehicle 1 can be shortened by reducing the moving speed. In FIG. 2B, the moving direction of the graphic element FU of the arrow is indicated by the broken line arrow.

Next, refer to FIG. 3 (A) to 3 (E) show changes in the positions of the left and right viewpoint images having parallax and the stereoscopic image having a sense of depth displayed in the distance with respect to the parallax angle difference in the parallax type 3D display. It is a figure which shows.

FIG. 3A shows an example of 2D display. One image (for example, a virtual image) V1 is displayed at a distance of D1 from the positions (viewpoint positions) of the left and right eyes EL and ER of the viewer. The convergence angle in this case is θ0. The parallax angle difference is 0 °.

FIG. 3B shows an example of a parallax type 3D display. In FIG. 3B, the viewpoint images (parallax images) V10 and V20 for the left and right eyes are juxtaposed along the left-right direction (width direction of the vehicle 1), but they are partially overlapped. ing. As a result, the image (virtual image) FU10 as a 3D display looks relatively close to the viewer. Note that D1 indicates the adjustment distance, D2 indicates the virtual distance, and D3 indicates the perceived distance.

FIG. 3C is a diagram illustrating the parallax angle difference in FIG. 3B. The parallax angle difference is represented by the difference between the convergence angle θ1 in FIG. 3B and the convergence angle θ2L or θ2R.

When Δθ shown on the lower side of FIG. 3B is the parallax angle difference and the value is positive, the stereoscopic image (stereoscopic image) FU10 is the display position (or the first) of the parallax images V10 and V20. If it is displayed on the back side of the surface) and the value is negative, the stereoscopic image (stereoscopic image) FU pops out toward the front side of the display positions (or the first surface) of the parallax images V10 and V20. It is displayed like this. In FIG. 3C, the parallax angle difference Δθ is positive, and its value is smaller than the predetermined threshold value θth.

See FIG. 3 (D). In FIG. 3D, D4 indicates a virtual distance and D5 indicates a perceived distance. The perceived distance D5 is larger than the perceived distance D3 in FIG. 3 (B). The left and right viewpoint images (parallax images) V30 and V40 are juxtaposed (separated) at intervals in the left-right direction. The stereoscopic image FU 20 is displayed on the back side (far position) of the stereoscopic image F10 of FIG. 3 (B) when viewed from the viewer. The parallax angle difference in this case is represented by Δθ'as shown in FIG. 3 (E). Δθ'is larger than the threshold value θth, and Δθ <Δθ'.

In this way, when the perceived distance increases, in other words, when the parallax angle difference increases, the distance between the left and right viewpoint images (left and right parallax images) increases, and the difference in appearance of each parallax image from the viewer's point of view becomes larger. Increase.

Therefore, when crosstalk (reverse vision, mixing, etc.) occurs, the distortion of the ghost image becomes larger in FIG. 3D than in FIG. 3B, and the viewer can clearly see the occurrence of crosstalk. I will recognize it. In other words, the farther the 3D representation of the 3D image is displayed, the easier it is for crosstalk to be recognized. Therefore, it is necessary to take measures against crosstalk in consideration of this point.

Next, refer to FIG. 4 (A) to 4 (E) are diagrams showing an example of a case where a process of reducing visibility corresponding to a perceived distance is performed as a measure against crosstalk. FIG. 4 (A) is the same as FIG. 3 (A). The perceived distance is D1. Here, the visibility of the 2D image V1 of FIG. 4A is assumed to be 100%.

FIG. 4B is the same as FIG. 3B. The perceived distance is D3 (> D1). FIG. 4C is the same as FIG. 3D. The perceived distance is D5 (> D3).

4 (D) and 4 (E) first carry out the display of FIG. 4 (A), then carry out the display of FIG. 4 (B), and then carry out the display of FIG. 4 (C). An example of the change in the visibility of the content image (display image) on the time axis is shown below. In FIG. 4D, a process of continuously reducing the visibility of the content image (a process of reducing the visibility as shown by the characteristic line G1) is executed when the perceived distance is increased. In FIG. 4E, a process of gradually reducing the visibility of the content image (a process of reducing the visibility as shown by the characteristic line G2) is executed. Any control may be used. However, when more accurate visibility control is required, it is preferable to adopt the continuous visibility reduction control shown in FIG. 4 (D).

In this way, as the perceived distance increases (in other words, as the display position of the image becomes farther), the visibility of the image decreases. As a result, the visibility of the ghost image due to crosstalk is also reduced, so that it is difficult for the viewer to recognize the crosstalk. Therefore, for example, a feeling of strangeness is reduced. Reducing discomfort also contributes to safe driving.

Further, the decrease in visibility in FIGS. 4 (D) and 4 (E) can be realized by, for example, reducing the brightness (gradation) of the image. Luminance can be rephrased as brightness. However, the present invention is not limited to this, and visibility may be controlled by adjusting the hue and saturation of the image.

In other words, the visibility reducing process may include at least one of a process of reducing the brightness (luminance) of the content image, a process of bringing the hue closer to blue, and a process of reducing the saturation.

For example, in the L ^* a ^* b ^* color space, the L ^* c ^* h ^* color space, etc. (these color spaces will be described later), the above three elements are appropriately changed to change the appropriate visibility. By controlling, it is possible to realize a 3D display in which cross talk is difficult to recognize.

For example, if the brightness (brightness) of the image is lowered, the brightness of the crosstalk image is also lowered, and it becomes difficult for the viewer to recognize the crosstalk. Specifically, for example, the display luminance of the content having a parallax angle difference of 0 ° is set as the maximum luminance, and the display luminance is lowered as the parallax angle difference increases.

Specifically, in the process of reducing the brightness of the image, in the 3DHUD device, the perceived distance (3D display distance) of the content image is calculated, and the dimming control of the TFT liquid crystal display device or the like according to the perceived distance of the content image is performed. It can be realized by implementing it. Further, as a method of controlling the brightness, it can also be realized by adaptively controlling the light intensity of the light source by using an active backlight or the like.

As explained earlier, a parallax angle difference of 0 ° means that a 2D image without parallax is displayed on the display surface of the left and right viewpoint images (referred to as the "first display surface") (left and right). The same image is visually recognized by each eye). In the case of 2D display, the image is located on the first display surface, but when the parallax angle difference becomes larger than 0 °, a stereoscopic image by 3D representation is placed deeper (farther) with respect to the first display surface. The image is displayed.

When the display surface of the stereoscopic image is the "second display surface", the distance between the "first display surface" and the "second display surface" is the "virtual distance", and the reference point on the viewer side. The distance from (for example, the viewpoint of the viewer) to the second display surface is the above-mentioned "perceived distance". As the virtual distance increases, a process of reducing the brightness (brightness) of the left and right viewpoint images displayed on the first surface is executed by, for example, a processor (reference numeral 742 in FIG. 9). It should be noted that the decrease in brightness (brightness) can be rephrased as "decrease in gradation", and can also be rephrased as "the tint approaches black".

Further, it is possible to reduce the visibility by shifting the color of the left and right viewpoint images toward the blue direction as the display position of the stereoscopic image by 3D representation shifts farther. In other words, by shifting the color scheme of the image toward the blue direction, which is said to have low human sensitivity, it is possible to make the display difficult to recognize crosstalk without changing the dimming parameters. The display color can be changed, for example, by changing the mixing ratio of the emitted light of a plurality of light sources having different emission colors. It is also possible to pass the emitted light through a blue filter to shift the hue toward the blue direction.

Also, due to the aerial perspective, distant objects tend to be more bluish and visible than similar objects placed nearby. Therefore, even when the color is changed in the blue direction, the expression is close to the actual landscape (distant view), and it is considered that the viewer does not feel uncomfortable with the displayed content, and no particular problem occurs.

When the initial value of the display content is the maximum value (MAX) of blue, it is not possible to shift to the blue direction, but even in this case, for example, the brightness (luminance) is lowered to change the color to black. It is possible to bring them closer and change the visibility. In addition, the visibility can be changed by reducing the saturation.

In addition, the saturation can be adjusted independently to change the visibility. For example, when a 3D representation stereoscopic image is in the vicinity, it is made a vivid color close to the primary color, and as it is far away, it is changed to a dull color, and finally it is made an achromatic color to control visibility. It is possible to do. The change of saturation can also be realized by the same method as the above-mentioned change of hue.

Further, the visibility reduction process may include a blurring process of gradually or continuously blurring the contour of the content image. By blurring the outline of the content image, the boundary between the crosstalk image (ghost image) and the original display image is blurred, and it is possible to provide a display in which crosstalk is difficult to recognize.

The blurring of the displayed image itself has some influence on the viewer. However, since the contour of the human eye looks hazy due to the aerial perspective as the display is farther away, even if the display image is blurred by the above processing, there is little discomfort with the content image, and there is no particular problem.

Next, refer to FIG. 5 (A) and 5 (B) are diagrams illustrating control of visibility using the L ^* a ^* b ^* color space. In the L ^* a ^* b ^* color space, the brightness (luminance) is represented by L ^* , and the chromaticity indicating hue and saturation is represented by a ^* b ^* . FIG. 5A shows the entire three-dimensional color space, and FIG. 5B shows a color plane representing hue and saturation. In FIG. 5B, for example, point A indicates "a hue in the red direction and a relatively bright color".

In the L ^* a ^* b ^* color space, the visibility of an image can be changed by appropriately changing the brightness (luminance), hue, and saturation.

Next, refer to FIG. FIG. 6 is a diagram illustrating control of visibility using an L ^* c ^* h ^* color space.

The L ^* c ^* h ^* color space is obtained by modifying the L ^* a ^* b ^* color space of FIG. L ^* represents lightness (luminance). c ^* represents the saturation. If this value is large, it will be located outside the circle, so it will be more brilliant, and if it is small, it will be closer to the center of the circle, resulting in a dull color.

Further, h ^* represents a hue angle. In FIG. 6, the + a ^* axis, which is the axis in the red direction, has a hue angle of 0 °, and a 90 ° counterclockwise shift results in a yellow hue, a 180 ° shift results in a green hue, and a 270 ° shift results in a blue direction. It becomes the hue of. In the L ^* c ^* h ^* color space, the hue can be directly specified by the hue angle, so that it is convenient when the color of the image described above is shifted in the blue direction.

(Second embodiment)
In the second embodiment, there is an example of preferable visibility control in a driving scene in which a moving first content image is displayed and the first content image is switched to a second content image having a different display mode. explain.

See FIG. 7. 7 (A) to 7 (D) are diagrams showing display examples using the first and second content images in the driving scene.

In FIGS. 7A to 7C, the graphic element FU1 of the arrow, which is a three-dimensional image, is a kind of navigation display for guiding the course (route) of the vehicle 1 while moving on the road surface 6. Here, The graphic element (AR element) FU1 of this arrow is referred to as a first content image.

The graphic element FU1 of the arrow, which is a three-dimensional image, is an augmented reality (AR) element of a moving body that moves so as to overlap the road surface 6 or to move away from the road surface at any time along the road surface 6. be. In FIGS. 7A to 7C, the movement path of the graphic element FU1 of the arrow is indicated by the broken line arrow.

Further, following FIG. 7C, in FIG. 7D, a graphic element (AR element) FU2 of an arrow for turning direction indicating a turning point is displayed as a second content image having a different display mode. Will be done. Specifically, the graphic element FU2 of the arrow for changing the direction is an arrow element for turning right that prompts a right turn. By shifting from FIG. 7C to FIG. 7D, switching from the first content image to the second content image is performed.

Further, in FIG. 7D, a vehicle speed display SP (display of "60 km / h") is displayed on the front side of the second content image FU2. The vehicle speed display SP is an image of non-superimposed content that is not intended to be superimposed on the actual scene.

When displaying the three-dimensional arrow graphic element FU1 that freely moves along the road surface 6, it is undeniable that it becomes difficult to accurately distribute the display light to each of the left and right eyes, and crosstalk occurs. Since it becomes easy, it is preferable to implement the crosstalk countermeasure by the visibility reduction treatment shown in the first embodiment.

However, when the visibility reduction process is also applied to the right-turn arrow graphic element FU2 shown in FIG. 7 (D), the direction change point is far away, so that the right-turn arrow graphic element FU2 can be visually recognized. The sex is considerably reduced. It is important that the graphic element FU2 of the arrow for turning right is surely visually recognized and recognized by the viewer (driver). In the state where the visibility is deteriorated, the viewer (driver) may not notice the graphic element FU2 of the arrow for turning right, and the vehicle 1 may inadvertently pass the turning point. Further, it is considered that the graphic element FU2 of the arrow for turning right is stationary or has less movement than the movement of FU1 which is a moving body. Therefore, it is considered that the frequency of crosstalk is lower than that of the moving body FU1.

Further, in the example of FIG. 7 (D), three graphic elements FU2 of arrows are arranged in the left-right direction (since the number of elements is one in FU1, the number is larger than the number of elements in FU1). Even if crosstalk occurs in the graphic element of one arrow, if the graphic elements of the other two arrows can be visually recognized normally, it is considered that there are few problems.

In consideration of these points, in the driving scene of FIG. 7 (D), the graphic element FU2 (second content image) of the arrow for turning right is determined by the viewer (driver) rather than the crosstalk countermeasure. Priority is given to points that are surely visually recognized and recognized, and control such as maintaining (ensuring) visible visibility is performed, for example. In other words, control that positively imparts visibility is implemented.

In this way, by considering the properties (attributes) of the first and second content images and implementing different visibility control for each, crosstalk can be prevented and important information can be confirmed reliably. Can be compatible with.

The first and second content images are not limited to the above example. Considering that the HUD device is not limited to in-vehicle use, in a broad sense, for example, the first content image is an augmented reality element indicating a moving object whose position is changed at any time, and the second content image is. It may be an augmented reality element that functions as a mark, a guide display, or a road sign that is superimposed on a specific point or a real scene in the vicinity of the point.

Specifically, the first content image may be a graphic element of an arrow that guides the course of a person. In addition, the second content image may be a guidance display (or a mark display) that prompts a person to turn right or left at a turning point, and is a road sign that prompts an action such as "pause, left / right confirmation". You may.

Further, assuming an in-vehicle HUD device, for example, the first content image is an augmented reality element (for example,) that moves along the road surface in order to guide the traveling of the vehicle on which the viewer (driver) is on board. , The graphic element FU1) of the three-dimensional arrow in FIG. 7, and the second content image is a mark or a guide display regarding the operation of the vehicle, which is superimposed on the actual scene at or near a specific point. , Or it may be an augmented reality element that functions as a road sign.

As a specific example of the second content image, for example, a graphic element (AR element) of an arrow for turning direction indicating a turning point (for example, a point of turning right or a left turn) can be mentioned. The graphic element of the turning arrow may include a display prompting a right curve or a left curve.

The graphic element of the arrow for changing the direction (example of the second content image) is considered to be a kind of guidance display. As another specific example, a road sign such as "display of a mark indicating the position of the destination" or "pause, driving, left / right confirmation" can be given. When displaying these as the second content image, it is prioritized to make the viewer surely see (confirm) as in the above example (example of the arrow element for changing the direction). Therefore, it is preferable to perform the same processing as in the above example. The meanings of the landmarks, guide signs, and road signs shall be interpreted flexibly in a broad sense. For example, the guidance display may include advertisements and signboards.

Further, the visibility of the second content image (for example, the graphic element FU1 of the arrow in FIGS. 7A to 7C) is located on the front side of the second content image when viewed from the viewer, and It is preferable to set the visibility lower than the visibility of an image that is not intended to be superimposed on the actual scene (an image of non-superimposed content: for example, a vehicle speed display SP displayed on the lower right side of FIGS. 7A to 7D).

The vehicle speed display, the display of the instrument of the vehicle, etc. are clearly displayed on the front side when viewed from the viewer (driver, etc.). Here, if the second content image displayed in the distance has the same visibility as the vehicle speed display or the like, the viewer will have two displays that are attracted, which is annoying. May be done. In consideration of this point, it is preferable that the visibility of the second content image in the distance is set lower than the visibility of the vehicle speed display on the front side.

Also, considering that the distant real scene looks hazy due to the aerial perspective, reducing the visibility of the second distant content image is consistent with the actual appearance of the distant scene, which is a particular problem. Does not occur.

Next, a specific example of visibility control will be described. See FIG. 8 (A) to 8 (H) are diagrams showing a control example of visibility and virtual distance in the display example of FIG. 7. Each of FIGS. 8A to 8D corresponds to each of FIGS. 7A to 7D.

In FIGS. 8A to 8D, D10 represents the adjustment distance, D21 to D23 represent the virtual distance, and D31 to D33 represent the perceived distance. Further, V11 and V12 are viewpoint images (parallax images) for the left eye / right eye displayed on the first display surface.

The graphic element FU1 of the three-dimensional arrow is displayed near the viewer in FIG. 8 (A), but is displayed slightly away from the viewer in FIG. 8 (B) and far away in FIG. 8 (C). The arrow. Further, since FU1 is drawn by the linear perspective method, the size of FU1 gradually decreases from FIG. 8A to FIG. 8C.

Further, FIG. 8 (E) shows the visibility of FU2 on the time axis (P: indicated by a solid characteristic line) and a virtual line when FIGS. 7 (A) to 7 (D) are sequentially displayed. An example of the change with the distance (L: indicated by the characteristic line of the broken line) is shown.

Further, FIG. 8 (F) is the same as FIG. 8 (D). FIG. 8G shows a display example in which the perceived distance (second perceived distance) of the second content image FU2 is shortened as the vehicle advances after FIG. 8F. In FIG. 8 (F), the second perceived distance is D33, but in FIG. 8 (G), it is D34 (<D33). However, in both FIGS. 8 (F) and 8 (G), the virtual distance is D23 and is maintained constant. Further, FIG. 8 (H) shows an example of changes in the visibility P (solid line) and the virtual distance L (broken line) in FIGS. 8 (F) and 8 (G) on the time axis. Note that V14 and V24 in FIGS. 8D and 8D are viewpoint images (parallax images) for the left and right eyes for displaying the three-dimensional second content image FU2.

As shown in FIGS. 8A to 8E, the control unit of the HUD device (reference numeral 701 in FIGS. 1 and 9A) perceives the first content image FU1 by the perceived distance changing process. Is increased to the first perceptual distance, and accordingly, the visibility of the first content image FU1 is reduced by the visibility reduction process, whereby the first content image is in a hidden state or a state close to it. (See around time t20 in FIG. 8 (E)).

Further, the control unit 701 has a visible visibility at the first perceptual distance or a second perceptual distance near the first perceptual distance during the perceptual distance change process or after the perceptual distance change process. It is possible to display the second content image FU2 whose display mode is different from that of the content image of 1.

As shown in FIGS. 8 (A) to 8 (C) and 8 (E), the visibility of the first content image FU1 gradually decreases as the perceived distance increases, and FIG. 8 (E) shows. Around time t20, the visibility becomes extremely low (hidden or close to it).

On the other hand, regarding the second content image (FU2 in FIG. 8D), the second content image FU1 has a second perceptual distance while the perceptual distance is continuously increasing or after the perceptual distance is increased. Visibility that is the same as or close to the first perceptual distance D33 of the content image FU1 of 1 (the same distance as the first perceptual distance D33 in FIG. 8E) and is visible. Is displayed.

This makes it possible to smoothly switch content images with less discomfort. In other words, at the timing when the second content image FU2 is displayed (near time t20 in FIG. 8E), the visibility of the first content image FU1 is considerably reduced, so that the two content images coexist. This prevents the two images from being clearly visible and causing confusion, thus reducing visual annoyance.

Further, unlike the first content image FU1 which is in a state close to non-display, the second content image FU2 is displayed with visible visibility, and this visual change (difference in visibility). ) Creates an attractiveness, and the viewer (driver or the like) is attracted to the second content image FU2, so that the second content image FU2 is surely visually observed. As a result, the information possessed by the second content image FU2 (for example, navigation information prompting a right turn) is surely transmitted to the viewer (driver or the like).

Further, the control unit (reference numeral 701 of FIGS. 1 and 9A) may increase the visibility for a certain period of time at the start of displaying the second content image FU2 and then reduce the visibility. In FIG. 8E, the visibility of the FU2 is temporarily increased from time t20 to t21 as shown by the dotted line, and the visibility is reduced and returned to the original state at t21 to t22. ..

In this way, the attractiveness of the second content image FU can be enhanced by controlling the visibility to be temporarily increased and then decreased at the display start time of the second content image FU. can. Therefore, the viewer (driver) can reliably see the newly displayed second content image FU2 without overlooking it.

Next, reference is made to FIGS. 8 (F) and 8 (G). After the visibility control for temporarily enhancing the visibility, the control unit 701 performs the perception distance of the second content image FU2 (second perception distance: D33 in FIG. 8 (F), D33 in FIG. 8 (G)). When D34) is shortened with the progress of the vehicle 1, the visibility of the second content image FU may be increased accordingly.

In FIG. 8H, a dotted line extends diagonally upward to the right from the solid line indicating visibility starting from time t31, which indicates a gradual increase in visibility as the perceived distance is shortened.

For example, when the second perceived distance is gradually shortened in response to the vehicle 1 approaching the turning point, the visibility can be increased according to the shortening of the distance. In other words, as the viewer and the position of the second content image get closer to each other, the visibility of the second content image is improved and the attractiveness of the second content image is increased. This ensures that the viewer does not overlook the second content image. Therefore, for example, a driving error such as the vehicle 1 inadvertently passing a turning point can be suppressed.

Further, after the control unit 701 starts displaying the second content image FU2, the second virtual distance (FIG. 8 (D) (or (F)) and FIG. 8) can be displayed in 3D during the period. D23) in (G) may be maintained. In FIG. 8 (G), the perceived distance D34 is shorter than that of D33 in FIGS. 8 (D) (or (F)), but the virtual distance D23 is maintained unchanged.

The viewer perceives the stereoscopic image at a position behind the display position (first surface) of the viewpoint image (parallax image) for each eye by a virtual distance. Therefore, if the second virtual distance is shortened or the like, a sense of incongruity may occur. Therefore, it was decided to maintain the second virtual distance as much as possible.

Further, when the control unit 701 shortens the perceived distance (second perceived distance D34) for the second content image FU2 in FIG. 8 (G), the control unit 701 maintains the virtual distance (second virtual distance) D23. However, the visibility of the second content image FU2 may not be deteriorated regardless of the shortening.

As described above, it is important for the second content image FU2 to be reliably viewed (confirmed) by the viewer (driver, etc.). Therefore, visibility is prioritized over crosstalk countermeasures, and visibility is reduced. Decided not to implement.

In the above description, the case where the 3D representation stereoscopic image is displayed behind the position (first surface) of the viewpoint image (parallax image) for each eye is illustrated. However, as described above, the 3D representation stereoscopic image may be displayed on the front side of the first surface.

In this case, the control unit 701 may set the visibility of the content image in 3D representation to be the same as or close to the visibility when the parallax angle difference is set to 0 ° and the display is 2D.

When the visibility (for example, display brightness) is lowered, it becomes difficult for the viewer (driver, etc.) to recognize that the three-dimensional content image is projected toward the front side. In other words, it causes a situation in which the viewer's perception of distance is reduced.

Therefore, in order to prevent this, the visibility (for example, display brightness) of the content image that pops out to the front when viewed from the viewer is not positively changed, and the visibility is the same as or close to the visibility of the 2D display. It is preferable to have sex.

Next, refer to FIG. FIG. 9A is a diagram showing an overall configuration example of a parallax type 3DHUD device capable of controlling a change in visibility as a measure against crosstalk, and FIG. 9B is a diagram showing a configuration example of a control unit and an image generation unit. Is. In FIG. 9A, the same reference numerals are given to the portions common to those in FIG. 1A.

The parallax type 3DHUD device includes a stereoscopic display device 111, an optical system 116, and an information acquisition unit 119. The stereoscopic display device 111 includes a display control device 700, an image generation unit 112, a display unit 113, and an actuator 179. The actuator 179 can be used, for example, to change the orientation of the curved mirror (concave mirror or the like) 117 included in the optical system 116.

The display control device 700 has a control unit 701. The control unit 700 is stored in the I / O interface 741, one or more processors 702, the memory 743, and the memory 743, and is configured to be executed by the one or more processors 702. It includes a plurality of computer programs PG. The processor 702 operates as a control unit 701 (functional block) that controls the image display by operating based on the computer program PG.

The control unit 701 displays a three-dimensional content image with a sense of depth by visually recognizing a left-viewpoint image and a right-viewpoint image having a difference between the left and right eyes of the viewer, and the content image is displayed. A perceptual distance change process that changes the perceptual distance, which is the distance perceived by the viewer, is executed, and the perceptual distance change process gradually or gradually changes the visibility of the content image when the perceptual distance increases. It includes a visibility reduction process (see FIGS. 4D and 4E) that continuously reduces the visibility.

In the example of FIG. 9B, the viewpoint position detection unit 44 is provided in order to analyze the image captured by the pupil image pickup camera 43 and detect the viewpoint position (and the line-of-sight direction).

Further, in FIG. 9B, the control unit 701 has a 3D / 2D switching necessity determination unit 751, a 3D display processing unit 752, and a perceptual distance change processing unit 753. The perception distance change processing unit 753 includes a visibility change processing unit 754. However, the visibility change processing unit 754 may be provided independently.

Further, the image generation unit 112 includes an image storage unit 312, a light field rendering unit 333, a left-eye image buffer 334, a right-eye image buffer 335, and an image interface (image I / F) 336.

Next, refer to FIG. FIG. 10 is a flowchart showing an example of the display control procedure. In step S1, the perceived distance (3D display distance) of the content image is determined. In step S2, 3D display processing is performed.

In step S3, it is determined whether or not the perceived distance needs to be changed. If it is Y, the process proceeds to step S4 and the visibility change process is performed. The change in visibility can be realized, for example, by adjusting at least one of brightness (luminance), hue, and saturation. If it is N in step S3, the process proceeds to step S5 to maintain the current 3D display.

In step S6, it is determined whether or not the display is finished. When it is Y, the display control is terminated, and when it is N, the process returns to step S1.

As described above, according to the present invention, in the parallax type 3D head-up display (HUD) device, as the perceived distance of the content image increases, the viewer can easily recognize the cross talk (cross talk). It can be effectively prevented from becoming noticeable).

In the present specification, the term vehicle can be broadly interpreted as a vehicle. In addition, terms related to navigation (for example, signs, etc.) shall be interpreted in a broad sense in consideration of, for example, the viewpoint of navigation information in a broad sense useful for vehicle operation. Further, the HUD device and the display device (and the display device in a broad sense) include those used as a simulator (for example, an aircraft simulator, a simulator as a game device, etc.).

The present invention is not limited to the above-mentioned exemplary embodiments, and those skilled in the art will be able to easily modify the above-mentioned exemplary embodiments to the extent included in the claims. ..

1 ... Vehicle (own vehicle), 2 ... Windshield (projected member), 3 ... HUD device display area (HUD display area), 5 ... Visualizer (user, driver, occupant) , Observer, etc.), 6 ... Ground or equivalent surface of the ground (road surface, etc.), 21 ... Area where parallax 3D display is possible (parallax 3D displayable area), 41 ... Dashboard, 43 ... Eye image pickup camera, 45 ... Surrounding image pickup camera, 46 ... Image processing unit, 47 ... Distance measurement unit, 48 ... Object type / size detection unit, 100 ... HUD device, 111: 3D display device, 112: image generation unit, 113: display unit (display panel, etc.), 114: light separation unit (lenticular lens, disparity barrier, etc.), 116: optical unit , 117 ... Curved mirror (concave mirror, etc.) 119 ... Information acquisition unit, 120 ... ECU, 123 ... Communication unit, 125 ... Radar unit, 700 ... Display control device, 701. Control unit, 741 ... I / O interface, 742 ... Processor, 743 ... Memory, 751 ... 2D / 3D switching necessity determination unit, 752 ... 3D display processing unit, 753. ... Perceived distance change processing unit, 754 ... Visibility change processing unit, K10, K20 ... Display light, PS ... Adjustment surface (imaging surface, first display surface), VS ... Congestion Surface (second display surface), D100 ... Adjustment distance, D200 ... Virtual distance (depth distance), D300 ... Perceived distance (3D display distance), FU ... 3D expression gives a sense of depth 3D image to have.

Claims (14)

A display control device that executes display control in a head-up display device that causes a viewer to visually recognize the image by projecting an image onto a projected member.
With one or more processors
With memory
It comprises one or more computer programs stored in the memory and configured to be executed by the one or more processors.
The processor functions as a control unit that controls image display by operating based on the computer program.
The control unit
A 3D display process for displaying a three-dimensional content image with a sense of depth by visually recognizing a left-viewpoint image and a right-viewpoint image having parallax to the left and right eyes of the viewer.
The perceptual distance changing process of changing the perceived distance, which is the distance perceived by the viewer, is executed.
The perceptual distance changing process is a display control device including a visibility reducing process that gradually or continuously reduces the visibility of the content image when the perceptual distance is increased. The visibility reduction process is
Of the content image
Processing to reduce brightness (brightness),
as well as,
Processing to bring the hue closer to blue,
as well as,
Processing to reduce saturation,
Including at least one of
The display control device according to claim 1. The visibility reduction process is
The outline of the content image is blurred stepwisely or continuously, including a blurring process.
The display control device according to claim 1 or 2. The control unit
Regarding the first content image as the content image, the perceived distance is increased to the first perceived distance by the perceived distance changing process, and accordingly, the visibility of the first content image is increased by the visibility decreasing process. Is reduced, thereby putting the first content image in a hidden state or a state close to it.
The first content has visible visibility at the first perceptual distance or a second perceptual distance near the first perceptual distance during the perceptual distance change process or after the perceptual distance change process. Displaying a second content image as the content image, which has a different display mode from the image.
The display control device according to any one of claims 1 to 3. The first content image is an augmented reality element indicating a moving object whose position is changed at any time.
The second content image is an augmented reality element having a function as a mark, a guide display, or a road sign, which is superimposed on a specific point or a real scene in the vicinity of the point.
The display control device according to claim 4. The first content image is an augmented reality element that moves along the road surface in order to guide the traveling of the vehicle on which the viewer is boarding.
The second content image is an augmented reality element having a function as a mark, a guide display, or a road sign regarding the operation of the vehicle, which is superimposed on a specific point or a real scene in the vicinity of the point.
The display control device according to claim 4. The adjustment distance is defined as the distance from the reference point set on the viewer side to the display position of the left viewpoint image and the right viewpoint image having the parallax.
The distance from the display position of the left viewpoint image and the right viewpoint image having the parallax to the position where the first content image or the second content image is perceived is the first virtual distance or the second virtual distance. As a distance
When the distance obtained by adding the first virtual distance to the adjusted distance is defined as the first perceived distance, and the distance obtained by adding the second virtual distance to the adjusted distance is defined as the second perceived distance.
The control unit
After starting the display of the second content image, the second virtual distance is maintained for a period in which 3D display is possible.
The display control device according to any one of claims 4 to 6. The control unit
When the second perceived distance of the second content image is shortened, the second perceived distance is shortened while maintaining the second virtual distance, but the visibility of the second content image is lowered regardless of the shortening. Don't let me
The display control device according to claim 7. The control unit
At the start of displaying the second content image, the visibility is increased for a certain period of time, and then the visibility is decreased.
The display control device according to any one of claims 4 to 8. The control unit
As the second perceptual distance is shortened, the visibility of the second content image is increased.
The display control device according to claim 9. The control unit
The visibility of the second content image is set lower than the visibility of an image that is located closer to the second content image and is not intended to be superimposed on the actual scene when viewed from the viewer. ,
The display control device according to any one of claims 4 to 10. The control unit
When displaying the content image on the front side of the positions of the left viewpoint image and the right viewpoint image having the parallax when viewed from the viewer, the content image is displayed.
The visibility of the content image is the same as or close to the visibility when the 2D display is performed with the parallax angle difference of 0 °.
The display control device according to any one of claims 1 to 11. A head-up display device that allows a viewer to visually recognize an image by projecting an image onto a projected member.
An image generation unit that generates the image and
A display unit that displays the image and
An optical system including an optical member that reflects the display light of the image and projects it onto the projected member.
The display control device according to any one of claims 1 to 12.
Head-up display device with. It is an image display control method.
The first step of determining the perceived distance, which is the distance perceived by the viewer of the content image,
A second step of performing a 3D display process of displaying a left-viewpoint image and a right-viewpoint image having parallax as a content image with a depth expression added to the left and right eyes of the viewer.
When the perceptual distance change process for changing the perceptual distance is performed, when the perceptual distance increases, the content image is visually recognized by adjusting at least one of the brightness, hue, and saturation of the content image. A third step of performing a visibility reduction treatment for gradually or continuously reducing the property, and a third step.
Image display control methods, including.

Images