JP2015120411A - Information display apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information display apparatus capable of showing the information of a direction to a driver.SOLUTION: If an actual direction of a display target relative to a vehicle itself is less than a given angle to a front-back direction of the vehicle itself, a directional image is formed so that a direction represented by the directional image on a screen of display means has a smaller angle than that of an actual direction to the display target, while if the actual direction is equal to or more than a given angle relative to the front-back direction of the vehicle itself, the directional image is formed so that a direction represented by the directional image on the screen of the display means has a larger angle than that of the actual direction.

Description

  The present invention relates to an information display device.

  As this type of technique, a technique described in Patent Document 1 below is disclosed. This document discloses one that displays an image at a position that does not obstruct the driver's central view. When guiding the driver to accelerate, a blue image is displayed, and when guiding the deceleration operation, a red image is displayed.

JP 2012-116439 A

With the technology described in Patent Document 1, direction information such as the direction of an obstacle with respect to the host vehicle and the course direction of the host vehicle cannot be shown to the driver.
The present invention pays attention to the above-mentioned problem, and an object of the present invention is to provide an information display device capable of showing direction information to the driver.

  In order to solve the above problems, in the present invention, when the actual direction to the display target with respect to the host vehicle is less than a predetermined angle with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image on the screen of the display means When the actual direction is greater than a predetermined angle with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image on the screen of the display means is larger than the actual direction. It was made to generate as follows.

  Therefore, the driver can accurately recognize the actual direction that the direction image is pointing to.

FIG. 2 is a control block diagram of the information display device of Example 1. FIG. 3 is a diagram illustrating an example of a direction image according to the first embodiment. 6 is a graph showing a difference between a direction indicated by a direction image before correction in Example 1 and a direction recognized by an observer. 3 is a graph showing contrast sensitivity with respect to a spatial frequency for each time frequency of Example 1. 3 is a graph showing contrast sensitivity with respect to a spatial frequency for each time frequency of Example 1. 3 is a graph showing contrast sensitivity with respect to a spatial frequency for each time frequency of Example 1. 4 is a table showing values of S1, S2, S3, P1, P2, and P3 in the formulas (2) and (3) of Example 1. 6 is a graph showing a visual field range having a contrast sensitivity with a maximum sensitivity of 10 [%] according to a time frequency of Example 1 for each spatial frequency. 4 is a graph showing a result of estimating, for each spatial frequency, a change in an eccentric angle of a visible range with respect to a change in time frequency in Example 1.

Example 1
[overall structure]
FIG. 1 is a control block diagram of the information display device 1. The information display device 1 includes an ambient condition monitoring unit 10, an ambient environment information detection unit 11, an other moving body information detection unit 12, a position information correction unit 13, an image generation unit 14, and a display device 15. ing.

  Ambient condition monitoring unit 10 receives a camera that captures the surroundings of the host vehicle, an obstacle sensor that transmits a signal around the host vehicle and receives a signal reflected by the obstacle, and a signal from a Global Positioning System (GPS) satellite It consists of a GPS receiver and detects obstacles around the vehicle.

The surrounding environment information detection unit 11 analyzes the signal from the surrounding state monitoring unit 10, detects a stopped obstacle around the own vehicle, and obtains the distance and direction of the obstacle with respect to the own vehicle.
The other moving body information detection unit 12 analyzes the signal from the surrounding state monitoring unit 10 to detect the moving obstacle around the own vehicle, and the distance and direction of the obstacle with respect to the own vehicle, the movement of the obstacle. Find the speed.

The position information correction unit 13 corrects the display direction when a direction image 17 described later is displayed on the display device 15. The position information correction unit 13 will be described in detail later.
The image generation unit 14 generates an image of the direction image 17 to be displayed on the display device 15.
The display device 15 is a liquid crystal display, and is installed at a position separated by 5 [°] or more with respect to the line of sight when the driver is gazing at the front of the host vehicle. Specifically, it is installed on the lower end of the windshield or on the instrument panel.

[Direction image]
FIG. 2 shows an image displayed on the display device 15. The direction image 17 is displayed so that the edge does not stand in time and space. As described above, the position of the display device 15 is 5 [°] or more, preferably 10 [°] -20 [°] away from the sight line direction (eccentric angle) when the driver is gazing in front of the host vehicle. By setting the position, the direction image 17 can be recognized in the driver's peripheral vision.

  The direction image 17 provides information on the direction to the driver. Information on the direction indicates a direction in which an obstacle is located with respect to the host vehicle, a course direction of the host vehicle, and the like. FIG. 2 shows an example of the front direction with respect to the host vehicle.

  The direction image 17 is indicated by a substantially circular display (hereinafter referred to as a circular display 17a). The luminance increases from the near side to the back, and the luminance decreases as it goes further. In FIG. 2, a plurality of circular displays 17a are shown in all of them, but actually, the circular display 17a is displayed as a moving image that repeatedly moves from the front to the back. The direction image 17 provides information on the direction to the driver according to the moving direction of the circular display 17a. For example, when indicating that there is an obstacle in the direction of about 40 [°] with respect to the front-rear direction of the host vehicle, the circular display 17a moves in the direction of about 40 [°] on the screen.

Further, the direction image 17 provides information on the distance between the host vehicle and the obstacle by variably displaying the cycle when the circular display 17a moves from the front toward the back as one cycle. Specifically, the display is performed such that the shorter the distance from the vehicle to the obstacle, the shorter the cycle. Further, as the distance is shorter, the circular display 17a is displayed so that the color changes from white-yellow-orange-red.
In the first embodiment, sound effects are generated in accordance with the display change period of the direction image 17. At this time, the sound field may be formed so that the sound moves in the direction indicated by the direction image 17.

[About correction of display direction of direction image]
As described above, the direction image 17 indicates information related to the direction. However, the direction displayed on the screen by the direction image 17 is corrected with respect to the actual direction with respect to the host vehicle to be displayed. This is because a deviation occurs between the direction indicated by the direction image 17 and the direction recognized by the driver.

  FIG. 3 is a graph showing a difference between the direction indicated by the direction image 17 before correction and the direction recognized by the observer in the experiment. In the experiment, the direction image 17 indicating each direction is displayed on the display placed below the face of the observer, and the observer recognizes the direction recognized, and the direction indicated by the direction image and the direction recognized by the observer The deviation was measured.

  In FIG. 3, when the direction image 17 indicates 0 [°], the direction recognized by the observer is also 0 [°]. The direction (angle) recognized by the observer is larger than the direction (angle) indicated by the direction image 17 until the direction indicated by the direction image 17 exceeds 0 [°] and is close to 40 [°]. If the angle exceeds 40 [°], the direction (angle) recognized by the observer is smaller than the direction (angle) indicated by the direction image 17.

  Therefore, in the first embodiment, the direction image to be displayed on the screen until the direction to be indicated by the direction image 17 (for example, the direction of the obstacle with respect to the host vehicle, hereinafter, the actual direction) exceeds 0 [°] and reaches 40 [°]. The direction indicated by 17 was corrected to be smaller than the actual direction. When the actual direction is 40 [°] or more, the direction indicated by the direction image 17 displayed on the screen is corrected to be larger than the actual direction.

[About the peripheral vision display]
The direction image 17 is made visible in the driver's peripheral visual field from a display with no edge in time and space. Thus, the direction image 17 can be visually recognized in the driver's peripheral vision, and the central vision can be prevented from being guided to the display device 15. Being able to visually recognize the direction image 17 by peripheral vision is not an essential condition for a driver who entrusts driving operation to automatic driving, but the condition that the central vision is not guided is a requirement for in-vehicle display.

The direction image 17 is the visual resolution of how much the driver can recognize as information with respect to the spatial frequency of the display around the visual field, and how much the driver recognizes as information with respect to the time frequency of display around the visual field. It uses the visual resolution that can be done. That is, the display of the direction image 17 is set in a range of spatial frequency and time frequency that can be read in the peripheral part of the visual field. Then, a display corresponding to the set spatial frequency and time frequency ranges is displayed in the driver's peripheral visual field and transmitted as information.
With such a display, information can be presented without inducing eye movement on the display device 15 even when the driver needs to gaze at the front in the vehicle traveling direction.

  Differences in visual characteristics that change depending on the region of the visual field range will be described. Fig. 4 shows how the contrast sensitivity to the spatial frequency when the temporal frequency changes varies with the degree of eccentricity (0 [°] to 50 [°]) upward from the center of the field of view. . FIG. 4 (a) is a diagram showing the contrast sensitivity with respect to the spatial frequency when the temporal frequency is 0.57 [Hz]. FIG. 4B is a diagram showing the contrast sensitivity with respect to the spatial frequency when the time frequency is 2.28 [Hz]. FIG. 4 (c) is a diagram showing the contrast sensitivity with respect to the spatial frequency when the time frequency is 9.12 [Hz].

  Fig. 5 shows how the contrast sensitivity to the spatial frequency when the temporal frequency changes varies with the degree of eccentricity (0 [°] to 90 [°]) in the left-right direction from the center of the field of view. . FIG. 5 (a) is a diagram showing the contrast sensitivity with respect to the spatial frequency when the temporal frequency is 0.57 [Hz]. FIG. 5B is a diagram showing the contrast sensitivity with respect to the spatial frequency when the time frequency is 2.28 [Hz]. FIG. 5 (c) is a diagram showing the contrast sensitivity with respect to the spatial frequency when the time frequency is 9.12 [Hz].

  Fig. 6 shows how the contrast sensitivity to the spatial frequency when the temporal frequency changes changes for each downward eccentricity (0 [°] to 50 [°]) from the center of the field of view. . FIG. 6 (a) is a diagram showing the contrast sensitivity with respect to the spatial frequency when the temporal frequency is 0.57 [Hz]. FIG. 6B is a diagram showing the contrast sensitivity with respect to the spatial frequency when the time frequency is 2.28 [Hz]. FIG. 6 (c) is a diagram showing the contrast sensitivity with respect to the spatial frequency when the time frequency is 9.12 [Hz].

  FIGS. 4 to 6 are based on the results of actual measurement by the subjects. The display patterns with the same luminance were presented to the two subjects, the contrast sensitivity was measured, and standardized with the maximum contrast sensitivity for each subject. The spatial frequency is a regression curve obtained for each eccentric angle under the assumption that the contrast sensitivity due to the peripheral region of the visual field continuously changes after standardization with the maximum spatial frequency having the standardized contrast sensitivity of 0.01. In addition, the eccentric angle is 0 [°] at the center of the field of view, and 5 [°], 10 [°], 20 [°], 30 [°], 50 [°], 70 [°], Increases to 90 [°].

  4 to 6, the horizontal axis represents the spatial frequency, and represents the roughness and fineness of the spatial luminance change in one display pattern image. The time frequency represents the speed of luminance change at an arbitrary position in the image and depends on the switching interval (frame interval) of the display pattern image.

  The vertical axis in FIGS. 4 to 6 is contrast sensitivity, and the minimum contrast at which the luminance change can be visually recognized {(maximum luminance-minimum luminance) / (Maximum luminance + minimum luminance)}.

  Furthermore, in FIGS. 4 to 6, the numerical value on the vertical axis is a value obtained by standardizing the contrast sensitivity of the maximum value obtained by reciprocal of contrast {(maximum luminance-minimum luminance) / (maximum luminance + minimum luminance)} as 1. . The numerical value on the horizontal axis is a numerical value that is standardized with 1 being the highest spatial frequency (maximum value of the cut-off frequency) detected as the contrast sensitivity.

  4 to 6, when the temporal frequency is low (0.57 [Hz]) and the central vision (eccentric angle 0 [°]), the contrast sensitivity is bandpass with respect to the spatial frequency. It is a characteristic of the mold. On the other hand, when the time frequency is medium (2.28 [Hz]) and the time frequency is high (9.12 [Hz]), the eccentric angle is not central (5 [°] to 90 [°]). In some cases, the contrast sensitivity is a low-pass characteristic with respect to the spatial frequency.

  That is, when the temporal frequency is low and central vision is present, there is a peak value of contrast sensitivity with respect to the spatial frequency, and at other times, the contrast sensitivity is higher as the spatial frequency is lower. In other words, when the speed of the luminance change of the display pattern displayed at the center of the subject's visual field is slow, there is a spatial frequency band where the display pattern is most accurately visually recognized by the subject.

  4 to 6, as the eccentric angle increases, the cut-off frequency, which is a spatial frequency at which the contrast sensitivity value is 0.01 in all directions, decreases (decrease in visual acuity). That is, a display pattern with a high spatial frequency and a fine luminance change becomes less visible as it is displayed at a position farther from the center of the visual field regardless of the orientation.

  As shown in FIGS. 4 to 6, as the eccentric angle increases, the maximum decrease in contrast sensitivity occurs in all directions. That is, regardless of the orientation, the more distant from the center of the visual field, the more difficult it is to visually recognize even a display pattern with a low spatial frequency.

  Next, as shown in FIG. 4 to FIG. 6 based on the actual measurement value, when the time frequency is changed, the contrast sensitivity to the spatial frequency is changed from the center of the visual field to the vertical and horizontal eccentric angles (0 [°] to 90 [ Explain that it can be obtained by calculation how it changes for each °]).

As this calculation method, low-pass characteristics are calculated except for band-pass characteristics with a low time frequency and an eccentric angle of 0 [°]. A function for obtaining the characteristics of the low-pass contrast sensitivity is expressed by the following equation (1).
S = 1-EXP {-EXP [-(Fs-Pp) / Sp]}… (1)

In Equation (1), S (Contrast Sensitivity) indicates contrast sensitivity, and Fs (Spatial Frequency) indicates spatial frequency. Further, the parameter Sp (Spread Parameter) in the equation (1) is expressed by the following equation (2). Further, the parameter Pp (Position Parameter) of the equation (1) is expressed by the following equation (23).
Sp = (S1 + S2) × Ec ^ S3… (2)
Pp = (P1 + P2) × Ec ^ P3 (3)

  Ec (Eccentricity) in the equations (2) and (3) is the retinal eccentric angle [Deg]. FIG. 7 is a table showing the values of S1, S2, S3, P1, P2, and P3. The values shown in FIG. 7 are assigned to S1, S2, S3, P1, P2, and P3 in the equation, respectively.

  Then, by continuously changing the value of the eccentric angle Ec to obtain the contrast sensitivity S, the contrast sensitivity for each eccentric angle in FIGS. 4 to 6 can be arbitrarily determined without depending on FIGS. The contrast sensitivity value for the spatial frequency at the corner can be complemented.

A function for obtaining a bandpass type characteristic with a low time frequency and an eccentric angle of 0 [°] is expressed by the following equation (4).
S = -0.015777 + 0.8141 × EXP {-POWER (LOG10 (Fs) +1.513,2) / POWER (0.815,2)}… (4)
In Equation (4), the spatial frequency Fs is a spatial frequency corresponding to the visual acuity of central vision, and the contrast sensitivity S can be calculated as a standardized value with the maximum sensitivity as 1.

  FIG. 8 shows, for each spatial frequency, a visual field range having a contrast sensitivity with a maximum sensitivity of 10 [%] according to the time frequency. FIG. 8 (a) shows the field of view when the time frequency is 0.57 [Hz]. FIG. 8 (b) shows the field of view when the time frequency is 2.28 [Hz]. FIG. 8 (c) shows a visual field range at a time frequency of 9.12 [Hz].

  The vertical and horizontal axes in FIG. 8 correspond to the vertical and horizontal axes of the visual field and represent the eccentric angle. In FIG. 8, as in FIG. 4, the spatial week standardized in the range of 0 to 1 shows the total value (minimum value 0.025). Note that the numerical value of the spatial frequency in FIG. 8 is a value when the spatial frequency Fa that can be visually recognized by the subject is 1, corresponding to the visual acuity Va of central vision (the reciprocal of the minimum separation value indicated by the visual angle). Here, since the spatial frequency Fa = 30 [Va] (Visual Acuiy: visual acuity), when the visual acuity is 0.7, the spatial frequency visible to the subject is Fa = 21 [cpd] (Cycles Per Degree). When the numerical value in FIG. 8 is 0.025, for example, it can be expressed as 0.025 × 21 = 0.53 [cpd].

  The change of the visual field range shown in FIG. 8 is also based on the actual measurement value with respect to the change of the visual field range by the subject, and for the azimuth without the actual measurement value, the ellipse is regressed between adjacent azimuths.

  From FIG. 8 (a) to FIG. 8 (c), the range in which the contrast sensitivity of 10 [%] is obtained is narrow in the upward visual field at any time frequency. From FIG. 8, it is possible to estimate the visible field range with respect to the spatial frequency. That is, as shown in FIGS. 8 (a) to 8 (c), the spatial frequency visible at the center of the visual field increases as the time frequency increases to 0.57 [Hz], 2.28 [Hz], and 9.12 [Hz]. , 0.40, 0.24, 0.16. However, the visible range in the peripheral part of the visual field is the widest at a medium time frequency (2.28 [Hz]).

  Thus, the visible range changes depending on the time frequency and the spatial frequency. FIG. 9 is a graph showing the result of estimating the change in the eccentric angle of the visible range with respect to the change in time frequency for each spatial frequency. In FIG. 9, the horizontal axis is the time frequency, and the vertical axis is the eccentric angle. From FIG. 9, it can be seen that as the spatial frequency decreases, the eccentric angle at which the contrast sensitivity can be obtained increases, and the viewing range in which the contrast sensitivity can be obtained becomes wider. In addition, the lower the spatial frequency, the higher the temporal frequency corresponding to the peak value of the eccentric angle.

  From this tendency, in Example 1, the direction image 17 is generated as an image having a spatial frequency of 1 [CPD] or less and a temporal frequency of 1-7 [Hz] as main components. Thus, when transmitting information by presenting an image to the driver, the contrast of the observer in the peripheral area of the visual field with respect to the peripheral area of the visual field away from the central visual field of the observer when in a standard posture It is possible to display a display pattern which is an image composed of frequency components in the range of the time frequency and the spatial frequency, which are the temporal frequency and the spatial frequency at which sensitivity is obtained, and which have no temporal edge and no spatial edge.

[Action]
As described above, there is a difference between the direction indicated by the direction image 17 and the direction recognized by the driver.

Therefore, in the first embodiment, when the actual direction that the direction image 17 intends to point is less than a predetermined angle with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image 17 on the screen of the display device 15 is an angle from the actual direction. When the actual direction is greater than the predetermined angle with respect to the longitudinal direction of the host vehicle, the direction indicated by the direction image 17 on the screen of the display device 15 is corrected so that the angle is larger than the actual direction. did.
Thus, the driver can accurately recognize the direction such as the direction of the obstacle and the course of the host vehicle.

In the first embodiment, when the actual direction is less than 40 [°] with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image 17 is corrected so that the angle is smaller than the actual direction. When the angle is 40 [°] or more with respect to the front-rear direction, the direction indicated by the direction image is corrected so that the angle is larger than the actual direction.
As a result, the driver can accurately recognize the actual direction that the direction image 17 intends to point to.

Further, in the first embodiment, the display device 15 is installed at a place 5 [°] or more away from the line-of-sight direction when the driver is gazing at the front of the host vehicle, and the direction image 17 has a spatial frequency of 1 [ [CPD] Below, the image is displayed as an image having no luminance edge whose main frequency is 1-7 [Hz].
Thus, the direction image 17 can be visually recognized in the driver's peripheral vision, and the central vision can be prevented from being guided to the display device 15.

In the first embodiment, the distance is indicated by periodically changing the display form of the direction image 17.
Thereby, in addition to the information regarding a direction, the driver | operator can also acquire the information regarding a distance.

In the first embodiment, the change period of the display mode of the direction image is shortened as the distance shown is shorter.
Thereby, the information regarding distance can be acquired easily.

In the first embodiment, sound effects are generated in synchronization with the change cycle of the display form of the direction image 17.
Thereby, the meaning of the display change of the display device 15 can be easily grasped, and the information regarding the distance can be easily acquired.

[effect]
(1) A display device 15 (display means) installed on the lower end of the windshield or on the instrument panel and displaying a direction image 17 indicating the direction to the display target with respect to the front-rear direction of the host vehicle on the screen, Ambient environment information detection unit 11 that detects the actual direction to the display target, another mobile body information detection unit 12 (real direction detection unit), and a unit that generates a direction image 17 to be displayed on the display device 15 Is less than a predetermined angle with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image 17 on the screen of the display device 15 is generated so that the angle is smaller than the actual direction toward the display target. When the angle is greater than or equal to a predetermined angle with respect to the front-rear direction of the vehicle, the position information correction unit 13 and the image generation unit 14 generate the direction indicated by the direction image 17 on the screen of the display device 15 so that the angle is larger than the actual direction. Direction Generation means).
Thus, the driver can accurately recognize the direction such as the direction of the obstacle and the course of the host vehicle.

(2) The position information correction unit 13 corrects the direction indicated by the direction image 17 so that the angle is smaller than the actual direction when the actual direction is less than 40 [°] with respect to the longitudinal direction of the host vehicle. When the angle is 40 [°] or more with respect to the longitudinal direction of the host vehicle, the direction indicated by the direction image is corrected so that the angle is larger than the actual direction.
Therefore, the driver can accurately recognize the actual direction that the direction image 17 intends to point to.

(3) The display device 15 is installed at a location 5 [°] or more away from the line-of-sight direction when the driver is gazing at the front of the host vehicle, and the image generation unit 14 creates the direction image 17 in the space The image is displayed as an image having no luminance edge whose main component is a frequency of 1 [CPD] or less and a time frequency of 1-7 [Hz].
Therefore, the directional image 17 can be visually recognized in the driver's peripheral vision, and the central vision can be prevented from being guided to the display device 15.

(4) The image generation unit 14 indicates the distance by periodically changing the display form of the direction image 17.
Therefore, the driver can acquire information related to the distance in addition to information related to the direction.

(5) The image generation unit 14 shortens the change cycle of the display mode of the direction image as the indicated distance is shorter.
Therefore, information regarding the distance can be easily acquired.

[Other Examples]
As described above, the present invention is not limited to the configuration of the above embodiment, and may have other configurations.
In the first embodiment, the direction image 17 is an image having no luminance edge whose main component is a spatial frequency of 1 [CPD] or less and a temporal frequency of 1-7 [Hz], but may be other images.

In the first embodiment, the circular display 17a is a moving image that repeatedly moves from the front to the back, but may be displayed by an arrow or the like, for example.
Further, the obstacle sensor shown by the ambient condition monitoring unit 10 may use a laser, an ultrasonic wave, or the like as a signal to be transmitted around the own vehicle, and is not particularly limited.

11 Ambient environment information detector (actual direction detection means)
12 Other moving body information detector (real direction detection means)
13 Position correction unit (direction image generation means)
14 Image generator (direction image generator)
15 Display device (display means)
17 direction image

Claims (5)

A display means installed on the lower end of the windshield or on the instrument panel and displaying a direction image indicating a direction to a display object with respect to the front-rear direction of the host vehicle on the screen;
Real direction detection means for detecting a real direction to the display object with respect to the host vehicle;
Means for generating a direction image to be displayed on the display means, and when the actual direction is less than a predetermined angle with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image on the screen of the display means is When the actual direction is greater than a predetermined angle with respect to the front-rear direction of the host vehicle, the direction indicated by the direction image is displayed on the screen of the display means. Direction image generation means for generating an angle larger than the actual direction;
An information display device characterized by comprising: In the information display device according to claim 1,
The direction image generation means corrects the direction indicated by the direction image so that the angle is smaller than the actual direction when the actual direction is less than 40 [°] with respect to the front-rear direction of the host vehicle. An information display device that corrects the direction indicated by the direction image so that the angle is larger than the actual direction when the angle is 40 [°] or more with respect to the front-rear direction of the host vehicle. In the information display device according to claim 1 or claim 2,
The display means is installed at a location 5 [°] or more away from the line of sight when the driver is gazing at the front of the host vehicle,
The direction image generation means displays the direction image as an image having no luminance edge whose main component is a spatial frequency of 1 [CPD] or less and a temporal frequency of 1-7 [Hz]. Display device. In the information display device according to any one of claims 1 to 3,
The information display apparatus according to claim 1, wherein the direction image generation means indicates a distance by periodically changing a display form of the direction image. In the information display device according to claim 4,
The information display device characterized in that the direction image generation means shortens the change cycle of the display form of the direction image as the distance shown is shorter.