Vehicle display device

Abstract

Even when visual information is presented to the driver while they are looking at the vehicle in front of them, such as a preceding vehicle, the information is presented without causing the driver any discomfort or unease due to double images caused by binocular parallax. [Solution] In a vehicle display device 10 installed in a vehicle V, which presents visible information emitted from a display unit 20 to the driver by reflecting it off the windshield, the display unit 20 displays the visible information while changing its position if the display distance of the visible information is within an area of ​​4m to 6m.

Description

Technical Field

[0001] The present invention relates to a display device for a vehicle.

Background Art

[0002] An AR-HUD (Augmented Reality Head-up Display) is known, which displays various types of information necessary for driving (road information, navigation information, etc.) on the windshield of a vehicle in a manner superimposed on the scenery that the driver is actually viewing.

Prior Art Literature

Patent Document

[0003]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0004] When the driver is viewing a preceding vehicle or the like, the driver's gazing point does not exist at a very close distance like the meter on the dashboard. Therefore, if display is performed at a very close distance by the AR-HUD, there is a risk that the display will be perceived by the driver as a double image due to binocular parallax.

[0005] Patent Document 1 repeatedly displays visual information having a predetermined length in the horizontal direction in the horizontal direction, and under predetermined conditions, makes the positions of the visual information perceived by the left and right eyes due to binocular parallax overlap, so that the driver can perceive one piece of visual information. However, there are restrictions on the horizontal width of the visual information, and it cannot be said that the driver's sense of discomfort has been sufficiently reduced.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a display device for a vehicle that can alleviate the annoyance and sense of discomfort caused by double images due to binocular parallax.

Means for Solving the Problems

[0007] To achieve the aforementioned objectives, the vehicle display device according to the present invention is characterized by the following: A vehicle display device installed in a vehicle that displays visible information emitted from a display unit and reflects it onto the windshield to present it to the driver, The aforementioned display device will change the position of the visible information when the display distance of the visible information is within an area of ​​4m to 6m. Vehicle display device. [Effects of the Invention]

[0008] According to the present invention, even when visual information is presented to a driver while they are looking at the area in front of the vehicle, such as a preceding vehicle, the information can be presented without causing the driver any discomfort or unease due to double images caused by binocular parallax.

[0009] The present invention has been briefly described above. Furthermore, the details of the present invention will be further clarified by referring to the attached drawings and reading through the embodiments for carrying out the invention described below (hereinafter referred to as "embodiments"). [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a block diagram of a vehicle display system including a vehicle display device according to the first embodiment of the present invention. [Figure 2] Figure 2 is a schematic diagram illustrating the situation in which a display unit displays visible information at a predetermined display distance. [Figure 3] Figure 3 shows the relationship between visible information, gaze point, and binocular parallax as seen from the driver's perspective. [Figure 4] Figure 4 is a conceptual diagram of the visible information displayed by the vehicle display device according to the first embodiment. [Figure 5] Figure 5 is a graph showing the relationship between the width of the visible information and the sensory evaluation value regarding the appearance of the visible information when the display distance is 2m in a sensory test. [Figure 6]Figure 6 is a graph showing the relationship between the width of the visible information and the sensory evaluation value regarding the appearance of the visible information in a sensory test when the display distance is 4m. [Figure 7] Figure 7 is a graph showing the relationship between the width of the visible information and the sensory evaluation value regarding the appearance of the visible information in a sensory test when the display distance is 6m. [Figure 8] Figure 8 is a graph showing the relationship between the width of the visible information and the sensory evaluation value regarding the appearance of the visible information in a sensory test when the display distance is 8m. [Figure 9] Figure 9 is a table summarizing the results of the sensory evaluation. [Figure 10] Figure 10 is a graph showing the relationship between display distance and the width of visible information, derived from the results of sensory evaluation, for displaying visual information that does not cause annoyance. [Figure 11] Figure 11 is a graph showing the brightness distribution of visible information when the distance to the preceding vehicle is large. [Figure 12] Figure 12 is a graph showing the brightness distribution of visible information when the distance to the preceding vehicle is short. [Figure 13] Figure 13 is a graph showing the relationship between the movement of visible information and the sensory evaluation value regarding the appearance of visible information in a second sensory test, for visible information displayed by a vehicle display device according to the second embodiment. [Figure 14] Figure 14 is a schematic diagram showing the movement of visible information displayed by a vehicle display device according to the second embodiment. [Figure 15] Figure 15 is a schematic diagram showing the movement of visible information displayed by a vehicle display device according to the second embodiment when turning right or left, where (A) shows the movement at a point far from the turning point, (B) shows the movement at a point close to the turning point, and (C) shows the movement at the point immediately adjacent to the turning point. [Figure 16] Figure 16 is a conceptual diagram of the visible information displayed by the vehicle display device according to the third embodiment. [Figure 17] Figure 17 is a graph showing the relationship between the amount of time visible information is presented and the percentage of people who find it bothersome. [Mode for Carrying Out the Invention]

[0011] Specific embodiments of the present invention will be described below with reference to the respective drawings.

[0012] (First Embodiment)] Figure 1 is a block diagram of a vehicle display system including a vehicle display device according to the first embodiment of the present invention. The vehicle display system 1 is installed in a vehicle, includes a vehicle display device 10 and a display 20, and is a system corresponding to a so-called AR-HUD.

[0013] The vehicle display device 10 includes a control unit 11, an operation unit 12, a storage unit 13, and an output unit 14. The control unit 11 is a so-called arithmetic processing device and processor, and is a computer that governs overall control of the entire vehicle display device 10. The operation unit 12 is a switch, button, touch panel or the like through which a vehicle driver or the like performs input for operating the vehicle display device 10. The storage unit 13 stores various programs, data and the like, and the control unit 11 reads, for example, the programs stored in the storage unit 13 to execute various processes by the vehicle display device 10 including the processes of the embodiments described later. The output unit 14 outputs, for example, an image generated by the control unit 11 to the display 20.

[0014] The display 20 is configured by a head-up display, a projector or the like that outputs the image output from the output unit 14. Figure 2 is a schematic diagram showing a situation where the display 20 displays visible information, which is a type of output image, at a predetermined display distance X [m]. The display 20 emits the visible information such that the visible information appears at a predetermined virtual display distance from the viewpoint of the driver M of the vehicle V. The visible information is reflected on the windshield of the vehicle V and presented at the predetermined display distance.

[0015] Figure 3 shows the relationship between visible information, gaze point, and binocular parallax from the perspective of driver M. Driver M is driving while looking at the scenery ahead, and driver M's gaze point is in the range of tens to hundreds of meters ahead. On the other hand, conventional vehicle display devices sometimes display visible information several meters away from driver M's viewpoint. In this case, due to the difference in distance between the gaze point and the visible information, and driver M's binocular parallax, the visible information appears as a double image to driver M, causing driver M to feel annoyed or uncomfortable.

[0016] Figure 4 is a conceptual diagram of the visible information displayed by the vehicle display device 10 according to the first embodiment. The visible information is, for example, Spot A, which is displayed to follow the preceding vehicle by ACC (Adaptive Cruise Control). Information such as Spot A is generally displayed several meters ahead. In conventional devices, if the driver M is driving while looking at the scenery ahead, for example, a distant vehicle ahead, Spot A may appear as a double image, which may cause annoyance or discomfort.

[0017] On the other hand, the vehicle display device 10 of this embodiment aims to alleviate the driver M's discomfort and discomfort by emitting visible information to a specific visible information emission area on the display unit 20, thereby resolving the problems of conventional devices. The vehicle display device 10 can also display other information (speed, navigation information, etc.) B as in conventional devices, but when viewing such information, the driver M generally shifts their gaze closer to the vehicle to confirm it, making the double image problem less likely to occur.

[0018] Next, the emission range of the visible information emitted by the display unit 20 will be explained. Generally, the emission range is defined by the display distance X mentioned above and the width Y [°] (the display angle range as seen from the driver M's viewpoint) from which the visible information is emitted. The inventor conducted a sensory test to verify whether a viewer who viewed the visible information felt annoyance or discomfort with the visible information, based on the setting of the width Y at a display distance X = 2m to 8m, which is generally set. Figures 5 to 8 are graphs showing the relationship between the width of the visible information and the sensory evaluation value regarding the appearance of the visible information at a specific display distance in the sensory test. The display distances for each graph are: Figure 5: display distance X = 2m, Figure 6: display distance X = 4m, Figure 7: display distance X = 6m, and Figure 8: display distance X = 8m. The width Y was set to values ​​of 1.5°, 3.1°, and 4.8°, which are within the generally set range.

[0019] The test results were evaluated using a five-point sensory evaluation scale (1, 2, 3, 4, 5). A sensory evaluation score of 1 indicates that the visual information is doubled, making the viewing experience very cumbersome. A sensory evaluation score of 5 indicates that the visual information is almost not doubled and there is almost no cumbersomeness. A sensory evaluation score of 3 falls between a sensory evaluation score of 1 and a sensory evaluation score of 5, indicating that the level of cumbersomeness is within an acceptable range (passing grade).

[0020] In Figure 5, when the display distance X was 2m, the display was cumbersome at all widths Y, and no acceptable results were obtained. In Figure 6, when the display distance X was 4m, no acceptable results were obtained at a width Y=1.5, but acceptable results were obtained at widths Y=3.1° and 4.8°. It was found that a width Y=2.4°, where the sensory evaluation value was 3, was the boundary value for acceptance between widths Y=3.1° and Y=4.8°.

[0021] In Figure 7, when the display distance X was 6m, an acceptable result was not obtained for a width Y = 1.5°, but acceptable results were obtained for widths Y = 3.1° and 4.8°. It was found that a width Y = 1.8°, where the sensory evaluation value was 3, was the boundary value for acceptance between widths Y = 1.5° and Y = 3.1°. In Figure 8, when the display distance X was 8m, acceptable results were obtained for all widths Y.

[0022] Figure 9 is a table summarizing the results of the sensory evaluation. The case where the display distance X is 8m is omitted. Figure 10 is a graph showing the relationship between the display distance and the width of the visible information, derived from the results of the sensory evaluation, for displaying visual information that does not cause annoyance. This graph was obtained by combining the test results from Figures 5 to 8.

[0023] From Figure 5, the setting of display distance X to 2m did not yield acceptable results and therefore cannot be adopted. From Figure 8, the setting of display distance X to 8m appears to be fine at first glance. However, extending the display distance would lead to an increase in the size of the display unit 20 due to image generation requirements, and setting the display distance X to 8m is not feasible from the standpoint of device size constraints.

[0024] Therefore, the inventors investigated the acceptable range of width Y for a display distance X of 4m or more and 6m or less. From the results in Figures 6 and 7, it was found that the equation y = -0.3x + 3.6, as shown in Figure 10, represents the boundary for acceptable width Y, and that acceptable results are obtained when the width Y is greater than or equal to this equation. In other words, based on the results of the sensory test, the vehicle display device 10 and the display unit 20 should emit visible information in a manner that satisfies the following conditions (3) and (4).

[0025] Y≧-0.3X+3.6 ···(3) 4 ≤ X ≤ 6 ···(4)

[0026] According to the vehicle display device 10 of this embodiment, even when visual information is presented to the driver while they are looking at the area in front of the vehicle, such as a preceding vehicle, the information can be presented without causing the driver any discomfort or unease caused by double images resulting from binocular parallax.

[0027] Figure 11 is a graph showing the brightness distribution of visible information when the distance to the preceding vehicle M1 is large. The vehicle display device 10 adjusts the brightness distribution of visible information I as shown in the graph, and the display unit 20 displays the visible information according to this brightness distribution.

[0028] In this example, the display unit 20 increases the brightness of visible information I in the central part a1 and decreases the brightness of visible information I in the peripheral part b1 as it approaches the outer edge. As a result, the brightness of visible information I decreases as it approaches the outer edge, further reducing the discomfort caused by the double image.

[0029] Due to this change in brightness information, the display unit 20 blurs the outer edge of the visible information I. This makes the change in the outer edge more gradual, further reducing the discomfort caused by the double image.

[0030] Figure 12 is a graph showing the luminance distribution of visible information I when the distance to the preceding vehicle M1 is short. The vehicle display device 10 adjusts the luminance distribution of visible information I as shown in the graph, and the display unit 20 displays the visible information according to this luminance distribution.

[0031] Figure 12 shows that, compared to the case where the distance to the preceding vehicle M1 is greater, as in Figure 11, the central area a2 with high brightness of visible information I is wider, and the peripheral area b2 with low brightness of visible information I is narrower. The closer the preceding vehicle M1 is, the closer the driver's gaze point becomes, and the double image problem decreases, so an appropriate brightness setting can be made according to the distance to the preceding vehicle M1.

[0032] (Second Embodiment) It is known that adding movement to visible information can reduce annoyance and discomfort. Therefore, the inventor conducted a third sensory test to verify how the annoyance and discomfort of the visible information changes for viewers when movement is added to the visible information. Figure 13 is a graph showing the relationship between the movement of the visible information and the sensory evaluation value regarding the appearance of the visible information in the third sensory test for the vehicle display device 10 according to the second embodiment.

[0033] This figure confirms that adding motion to visible information can alleviate the discomfort caused by double images.

[0034] Figure 14 is a schematic diagram showing the movement of visible information displayed by the vehicle display device 10 according to the second embodiment. The visible information in this figure is an arrow pointing in a specific direction. As in this example, adding movement is a suitable technique for displays that point in a specific direction or guide a vehicle (such as route guidance).

[0035] If the visible information is a single movement, the driver may not notice it; therefore, it is desirable to present the visible information multiple times. In this case, if the repetition frequency is too high, it may be perceived as annoying or dangerous, so a display with repetition at a frequency of approximately 1 Hz or less is desirable.

[0036] Figure 15 is a schematic diagram showing the movement of visible information displayed by the vehicle display device 10 according to the second embodiment when making a right turn, where (A) shows the movement at a point far from the right turn point, (B) shows the movement at a point close to the right turn point, and (C) shows the movement at a point immediately adjacent to the right turn point. For example, when informing the driver of a right or left turn point, if the display shows arrows repeatedly scrolling by, it may be difficult for the driver to determine when to turn. Therefore, as shown in Figure 15, it is effective to change the display mode of the visible information as the vehicle approaches the turning point (a right turn point in this example).

[0037] In this example, as the vehicle approaches the right-turn point, the distance over which the visible right-pointing arrow moves gradually increases, and the display size also gradually increases. The display method is not particularly limited and may change from a hollow display to a solid-color display, for example. The number of moving arrows may also be changed. For example, one arrow may be displayed in the first display, two in the second display, three in the third display, and so on, increasing the number of arrows displayed. In addition, at least one of the visible information's size, color, speed of movement, and period may be changed depending on the distance between the vehicle and the target point.

[0038] Furthermore, the movement of visible information is not limited to the horizontal direction as shown in Figures 14 and 15; movement in any direction is permitted as long as the display distance remains within the range.

[0039] (Third embodiment) Figure 16 is a conceptual diagram of the visible information displayed by the vehicle display device 10 according to the third embodiment. In this embodiment, the visible information is a lane L displayed in correspondence with a lane detected by, for example, LKA (Lane Keeping Assist System), instead of the ACC spot A in the first embodiment. The content of the visible information is not particularly limited.

[0040] The inventor noticed that when visual information is presented for a long time, viewers are more likely to begin to feel annoyed by the double image, and investigated the relationship between the presentation time of visual information and the percentage of people who feel annoyed. Figure 17 is a graph showing the relationship between the presentation time of visual information and the percentage of people who feel annoyed by the double image, as obtained from the investigation.

[0041] This graph suggests that when the presentation time of visible information is 1.3 seconds or less, the percentage of people who experience discomfort due to double images drops to 10% or less, and when the presentation time of visible information is 1.2 seconds or less, the percentage of people who experience discomfort drops to 5% or less.

[0042] Therefore, by setting the presentation time of visible information to 1.3 seconds or less, the discomfort caused by double images can be further reduced for most drivers. Furthermore, setting it to 1.2 seconds or less is even more preferable, as it can further reduce the discomfort caused by double images for almost all drivers.

[0043] Furthermore, such visible information during the presentation time may include flashing displays of visible information, or animations in which the display position or content changes within these presentation times.

[0044] The contents of the first to third embodiments can be implemented individually or in combination.

[0045] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to these examples. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention. Furthermore, the components of the above embodiments may be combined in any way without departing from the spirit of the invention.

[0046] Herein, the features of the embodiments of the vehicle display device according to the present invention described above are briefly summarized and listed below in [1] to [3].

[0047] [1] A vehicle display device (vehicle display device 10) installed in a vehicle (vehicle V) that displays visible information emitted from a display device (display device 20) and reflects it onto the windshield to present it to the driver, The aforementioned display unit will change the position of the visible information when the display distance (X) of the visible information falls within an area of ​​4m to 6m. Vehicle display device.

[0048] According to the vehicle display device configuration described in [1] above, even when visual information is presented to the driver while they are looking at the vehicle ahead, such as a preceding vehicle, the information can be presented without causing the driver any discomfort or unease due to double images caused by binocular parallax.

[0049] [2] The display device displays the visible information such that the repetition period of the moving pattern is 1 Hz or less. The vehicle display device described in [1] above.

[0050] According to the vehicle display device configuration described in [2] above, it is possible to suppress the driver from feeling annoyed or threatened due to a high repetition cycle.

[0051] [3] The display device displays visible information by changing at least one of the size, color, speed of movement, and period according to the distance between the vehicle and the target point. The vehicle display device described in [1] above.

[0052] According to the vehicle display device configuration described in [3] above, the driver can perceive the distance from the vehicle to the target point by changes in visible information. [Explanation of Symbols]

[0053] 1. Vehicle display system 10 Vehicle display devices 11 Control Unit 12 Control section 13 Storage section 14 Output section 20 Display

Claims

1. A vehicle display device installed in a vehicle that displays visible information emitted from a display unit and reflects it onto the windshield to present it to the driver, The aforementioned display device will change the position of the visible information when the display distance of the visible information is within an area of ​​4m to 6m. Vehicle display device.

2. The display device displays the visible information so that the repetition period of the moving pattern is 1 Hz or less. The vehicle display device according to claim 1.

3. The display device changes at least one of the size, color, speed of movement, and period of visible information according to the distance between the vehicle and the target point. The vehicle display device according to claim 1.

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