JP7757883B2 - Vehicle display control device and vehicle display control method - Google Patents

Description

This disclosure relates to a vehicle display control device and a vehicle display control method.

As we move towards a carbon-neutral society, there is an increasing need for energy conservation. In response to this, technologies are known for reducing the power consumption of displays installed in vehicles. Patent Document 1 discloses a technology for reducing the brightness of displays installed in a vehicle that are not in the driver's line of sight.

Japanese Patent Application Laid-Open No. 2021-24402

Increasing power consumption due to larger display screens installed in vehicles is an issue. In response to this, the technology disclosed in Patent Document 1 does not reduce the brightness of the entire display screen if the driver's gaze is directed at even a part of the screen. This results in wasted power consumption due to maintaining the brightness of the screen outside the area where the driver is likely to gaze (hereinafter referred to as the visible area).

In response to this, one approach is to reduce the brightness of areas outside the visible area (hereinafter referred to as non-visible areas) within the screen of a single display. However, reducing the brightness of non-visible areas to match the speed of the visible area, which moves in conjunction with the driver's line of sight, is thought to cause problems. This is because the sudden change in brightness at the transition from the visible area to the non-visible area is perceived by the driver's peripheral vision, causing discomfort to the driver.

One objective of this disclosure is to provide a vehicle display control device and a vehicle display control method that minimizes unnecessary power consumption by the display, even when the screen of the display installed in the vehicle is enlarged, while minimizing the discomfort felt by the occupants.

The above object is achieved by the combination of features recited in the independent claims, and the subclaims define further advantageous embodiments of the disclosure. The reference numerals in parentheses in the claims indicate a correspondence with the specific means described in the embodiments described below as one aspect, and do not limit the technical scope of the present disclosure.

In order to achieve the above object, a first vehicle display control device of the present disclosure is a vehicle display control device that is used in a vehicle and includes a display control unit (104) that is capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle, and includes an area identification unit (102) that sequentially identifies a visual recognition area, which is an area that is estimated to be an area that an occupant of the vehicle is likely to gaze at, based on the result of detecting an occupant of the vehicle, and the display control unit controls the brightness of a non-visual recognition area, which is outside the area identified by the area identification unit as a visual recognition area, within the display area of one display device, to be lowered compared to when the area is identified as a visual recognition area, in accordance with the movement of the visual recognition area sequentially identified by the area identification unit, and controls the brightness change of an area that changes from a visual recognition area to a non-visual recognition area within the display area of one display device to be lower than a reference degree of change when transitioning from a non-visual recognition area to a visual recognition area, The area identification unit sequentially identifies the visible area for each of the multiple occupants in the display area of one display when there are multiple occupants in the vehicle, and the display control unit controls, for the driver of the vehicle, the area of one display that changes from a visible area to a non-visible area so that the change in luminance in response to the change is slower than the standard degree of change, and controls, for the area that changes from a non-visible area to a visible area so that the change in luminance in response to the change is at the standard degree of change, while, for passengers other than the driver of the vehicle, the area of the display that changes from a visible area to a non-visible area and the area that changes from a non-visible area to a visible area are both controlled to change more slowly than the standard degree of change .
In order to achieve the above object, a second vehicle display control device of the present disclosure is a vehicle display control device that is used in a vehicle and includes a display control unit (104) that is capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle, and includes an area identification unit (102) that sequentially identifies a visual recognition area that is an area that is estimated to be an area that an occupant is likely to gaze at based on a result of detecting an occupant of the vehicle, and the display control unit controls the brightness of a non-visual recognition area that is outside the area identified by the area identification unit as a visual recognition area within the display area of one display device to be lowered compared to when the area is identified as a visual recognition area, in accordance with the movement of the visual recognition area sequentially identified by the area identification unit, and for an area within the display area of one display device that changes from a visual recognition area to a non-visual recognition area, the display control unit controls the brightness of the non-visual recognition area to be lower compared to when the non-visual recognition area is identified as a visual recognition area, in accordance with the movement of the visual recognition area sequentially identified by the area identification unit. The display control unit controls the change in luminance for a region of the display area of one display device that changes from a visible region to a non-visible region so that the change in luminance for that change is slower than the reference degree of change when transitioning from a non-visible region to a visible region, and when the vehicle is running, controls the change in luminance for a region that changes from a non-visible region to a visible region so that the change in luminance for that change is at the reference degree of change, while when the vehicle is stopped, controls the change in luminance for both a region that changes from a visible region to a non-visible region and a region that changes from a non-visible region to a visible region so that the change is at the reference degree of change.
In order to achieve the above object, a third vehicle display control device of the present disclosure is a vehicle display control device that is used in a vehicle and includes a display control unit (104) that is capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle, and includes an area identification unit (102) that sequentially identifies a visual recognition area that is an area that is estimated to be an area that the occupant is likely to gaze at based on a result of detecting the vehicle occupant, and the display control unit controls the brightness of a non-visual recognition area that is outside the area identified by the area identification unit as a visual recognition area within the display area of one display device in accordance with movement of the visual recognition area sequentially identified by the area identification unit so as to be lowered compared to when the area is identified as a visual recognition area, and for an area that changes from a visual recognition area to a non-visual recognition area within the display area of one display device, a change in brightness in response to the change is controlled to be lower than the brightness of the non-visual recognition area. The vehicle is capable of switching between manual driving and autonomous driving, and the display control unit controls, when the vehicle is in manual driving mode, the change in brightness of an area of a display device that changes from a visible area to a non-visible area so that the change in brightness in response to the change is slower than the standard change degree, and controls the change in brightness of an area that changes from a non-visible area to a visible area so that the change is at the standard change degree, while when the vehicle is in autonomous driving mode, the display control unit controls both the area of the display device that changes from a visible area to a non-visible area and the area that changes from a non-visible area to a visible area so that the change is at the standard change degree.
In order to achieve the above object, a fourth vehicle display control device of the present disclosure is a vehicle display control device that is used in a vehicle and includes a display control unit (104) that is capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle, and includes an area identification unit (102) that sequentially identifies a visual recognition area that is an area that is estimated to be an area that the occupant is likely to gaze at based on the result of detecting the vehicle occupant, and the display control unit adjusts the brightness of a non-visual recognition area that is outside the area identified as the visual recognition area by the area identification unit within the display area of one display device, in accordance with the movement of the visual recognition area sequentially identified by the area identification unit. The display control unit controls the brightness of the display area of one display device to be lower than when the brightness is set to a predetermined value, and for an area of the display area of one display device that changes from a visible area to a non-visible area, the change in brightness in response to that change is controlled to be slower than the reference degree of change when transitioning from a non-visible area to a visible area, and when the display control unit controls the brightness of the display area of one display device to change more slowly than the reference degree of change in accordance with the movement of the visible area sequentially identified by the area identification unit, the display control unit controls the change to be slower on a content-by-content basis displayed in the display area.

In order to achieve the above object, a first vehicle display control method of the present disclosure is a vehicle display control method that includes a display control step executed by at least one processor and that is used in a vehicle and capable of partially controlling brightness within a display area of a display device (14) mounted on the vehicle, and includes a region specifying step of sequentially specifying a visible region that is a region that is estimated to be a region that the occupant is likely to gaze at, based on a result of detecting an occupant of the vehicle, and the display control step controls the brightness of a non-visible region, which is outside the region specified as the visible region in the region specifying step, of the display area of one display device in accordance with movement of the visible region sequentially specified in the region specifying step, to be lowered compared to when the region is specified as the visible region, and for a region that changes from the visible region to the non-visible region of the display area of one display device, a change in brightness corresponding to the change is controlled based on a reference change degree when transitioning from the non-visible region to the visible region. In the area specifying step, when there are multiple occupants in the vehicle, the visible area for each of the multiple occupants in the display area of one display is sequentially specified, and in the display control step, for the driver of the vehicle, for an area in the display area of one display that changes from a visible area to a non-visible area, the change in luminance in response to the change is controlled to be slower than the reference degree of change, and for an area that changes from a non-visible area to a visible area, the change in luminance in response to the change is controlled to change at the reference degree of change, while for passengers other than the driver of the vehicle, the change is controlled to be slower than the reference degree of change for both the area that changes from a visible area to a non-visible area and the area that changes from a non-visible area to a visible area in the display area .
In order to achieve the above object, a second vehicle display control method of the present disclosure is a vehicle display control method that includes a display control step executed by at least one processor and that is used in a vehicle and capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle, and includes a region specifying step of sequentially specifying a visible region that is an area that is estimated to be an area that the occupant is likely to gaze at based on a result of detecting an occupant of the vehicle, and in the display control step, in accordance with the movement of the visible region sequentially specified in the region specifying step, the brightness of a non-visual region, which is outside the region specified as the visible region in the region specifying step, is controlled to be lowered compared to when it is specified as the visible region, and for a region of the display area of the one display that changes from a visible region to a non-visual region, In the display control process, when the vehicle is traveling, the change in luminance in a region of the display area of one display that changes from a visible region to a non-visible region is controlled to change slowly compared to the reference degree of change, and the change in luminance in a region that changes from a non-visible region to a visible region is controlled to change at the reference degree of change, while when the vehicle is stopped, the change in luminance in both the region that changes from a visible region to a non-visible region and the region that changes from a non-visible region to a visible region in the display area of the display is controlled to change at the reference degree of change.
In order to achieve the above object, a third vehicle display control method of the present disclosure is a vehicle display control method executed by at least one processor, used in a vehicle capable of switching between manual driving and autonomous driving, and including a display control step capable of partially controlling brightness within a display area of a display device (14) mounted on the vehicle, and including an area specifying step of sequentially specifying a visible area, which is an area estimated to be an area where the occupant is likely to gaze, based on a result of detecting an occupant of the vehicle, and in the display control step, in accordance with movement of the visible area sequentially specified in the area specifying step, controlling the brightness of a non-visual area, which is outside the area specified as the visible area in the area specifying step, to be lowered compared to when it is specified as the visible area, and In the display control process, when the vehicle is being manually driven, the luminance change in a region of a display device that changes from a visible region to a non-visible region is controlled to be slower than the reference degree of change, and the luminance change in a region that changes from a non-visible region to a visible region is controlled to be the reference degree of change, while when the vehicle is being automatically driven, the luminance change in both the region that changes from a visible region to a non-visible region and the region that changes from a non-visible region to a visible region is controlled to be the reference degree of change.
In order to achieve the above object, a fourth vehicle display control method of the present disclosure is a vehicle display control method that includes a display control step executed by at least one processor and that is used in a vehicle and capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle, and includes a region specifying step of sequentially specifying a visible region that is an area that is estimated to be an area that the occupant is likely to gaze at based on a result of detecting the vehicle occupant, and in the display control step, the brightness of a non-visible region of the display area of one display device that is outside the region specified as the visible region in the region specifying step is controlled in accordance with movement of the visible region sequentially specified in the region specifying step. The brightness of the display area of one display device is controlled to be lower than when the area is identified as a visible area, and for an area of the display area of one display device that changes from a visible area to a non-visible area, the change in brightness in response to that change is controlled to be slower than the standard degree of change when transitioning from a non-visible area to a visible area, and in the display control process, when the brightness of the display area of one display device is controlled to change more slowly than the standard degree of change in accordance with the movement of the visible area that is sequentially identified in the area identification process, the change is controlled to be slower for each content displayed in the display area.

As a result, the brightness of non-visible areas, which are outside the visible area of a display device and are estimated to be areas where the occupant is likely to gaze, is reduced compared to when the area is identified as a visible area. This makes it possible to reduce power consumption for areas of a display device that are outside the visible area. Furthermore, for areas that change from a visible area to a non-visible area, the change in brightness corresponding to this change can be made slower than the standard degree of change when transitioning from a non-visible area to a visible area. This makes it difficult for the occupant's peripheral vision to detect a sudden change in brightness in the area that switches from the visible area to the non-visible area. As a result, even when the screen of a display device installed in a vehicle is enlarged, it is possible to reduce wasted power consumption of the display while minimizing discomfort to the occupant.

1 is a diagram illustrating an example of a schematic configuration of a vehicle system 1. FIG. FIG. 2 is a diagram illustrating an example of a schematic configuration of an HCU 10. 10A and 10B are diagrams for explaining an example of region identification by a region identification unit 102. 10A and 10B are diagrams for explaining an example of a change in area depending on the face direction of an occupant. FIG. 10 is a diagram illustrating an example of a change in luminance in response to a change in area. 10A and 10B are diagrams for explaining an example of a change in luminance of a non-visual transition region when the control of the present disclosure is not performed. 10A and 10B are diagrams for explaining an example of a change in luminance of a non-visual transition region when the control of the present disclosure is performed. 10A and 10B are diagrams for explaining an example of changes in area depending on the facial orientation of each of a plurality of occupants. FIG. 10 is a diagram illustrating an example of a change in luminance in response to a change in area. 10 is a flowchart showing an example of the flow of a brightness control-related process in the HCU 10.

Multiple embodiments of the disclosure will be described with reference to the drawings. For ease of explanation, parts in multiple embodiments that have the same functions as parts shown in figures used in previous explanations will be assigned the same reference numerals, and their description may be omitted. For parts assigned the same reference numerals, reference may be made to the explanations in other embodiments.

(Embodiment 1)
<General Configuration of Vehicle System 1>
A first embodiment of the present disclosure will be described below with reference to the drawings. A vehicle system 1 shown in FIG. 1 can be used in a vehicle. As shown in FIG. 1, the vehicle system 1 includes an HCU (Human Machine Interface Control Unit) 10, an autonomous driving ECU 11, a vehicle state sensor 12, an interior camera 13, and a display 14. For example, the HCU 10, the autonomous driving ECU 11, and the vehicle state sensor 12 may be configured to be connected to an in-vehicle LAN (see the LAN in FIG. 1). The following description will be given taking as an example a case where the vehicle using the vehicle system 1 is an automobile. Note that the vehicle using the vehicle system 1 does not necessarily have to be an automobile. The vehicle using the vehicle system 1 will be referred to as the host vehicle hereinafter.

The autonomous driving ECU 11 is an electronic control device that includes, for example, a processor, memory, I/O, and a bus connecting these. The autonomous driving ECU 11 executes control programs stored in the memory to perform autonomous driving-related processes. The autonomous driving ECU 11 is capable of switching the degree of autonomous driving of the vehicle (hereinafter referred to as the automation level). There can be multiple automation levels, as defined by, for example, the SAE. Automation levels are classified, for example, from level 0 to 5 as follows:

Level 0 is the level at which the driver performs all driving tasks without intervention from the vehicle's systems. Driving tasks can also be referred to as dynamic driving tasks. Examples of driving tasks include steering, acceleration/deceleration, and peripheral monitoring. Level 0 corresponds to so-called manual driving. Level 1 is the level at which the system assists with either steering or acceleration/deceleration. Level 1 corresponds to so-called driver assistance. Level 2 is the level at which the system assists with both steering and acceleration/deceleration. Level 2 corresponds to so-called partial driving automation. Levels 1 and 2 are also considered part of automated driving. Level 3 is the level at which the system can perform all driving tasks in specific locations, such as highways, and the driver takes over driving operations in emergencies. At Level 3, the driver is required to respond quickly when the system requests a takeover. Level 3 corresponds to so-called conditional driving automation. Level 4 is the level at which the system can perform all driving tasks except under certain circumstances, such as on roads that cannot be handled or in extreme environments. Level 4 corresponds to so-called high driving automation. Level 5 is the level at which the system can perform all driving tasks in all environments. Level 5 corresponds to fully automated driving.

The vehicle in this embodiment may be configured to be able to switch between only some of the automation levels from level 0 to level 5. In this embodiment, an example will be described in which the vehicle can switch between manual driving and automated driving at level 1 or higher.

The vehicle condition sensor 12 is a group of sensors for detecting various conditions of the vehicle. Examples of the vehicle condition sensor 12 include a vehicle speed sensor and a shift position sensor. The vehicle speed sensor detects the vehicle speed of the vehicle. The shift position sensor detects the shift position of the vehicle. The vehicle condition sensor 12 outputs the detected sensing information to the in-vehicle LAN. Note that the sensing information detected by the vehicle condition sensor 12 may also be configured to be output to the in-vehicle LAN via an ECU installed in the vehicle.

The interior camera 13 captures a specified range within the vehicle's interior. It is preferable that the interior camera 13 captures an area that includes at least the driver's seat of the vehicle. It is more preferable that the interior camera 13 captures an area that includes the passenger seat in addition to the driver's seat of the vehicle. The interior camera 13 may capture an area that includes the passenger seat and rear seats in addition to the driver's seat of the vehicle. There may be multiple interior cameras 13.

The interior camera 13 is composed of, for example, a near-infrared light source, a near-infrared camera, and a control unit that controls them. Images captured by the near-infrared camera are analyzed by the control unit. The control unit detects the presence of an occupant using image recognition technology. The control unit detects the presence of an occupant by recognizing the occupant's face. The control unit analyzes the captured image to detect facial features of the occupant. The control unit detects the occupant's facial direction based on the detected facial features of the occupant. As an example, the control unit may detect the occupant's facial direction from the relative positional relationship of each part of the face. The facial direction angle may be expressed, for example, by defining the occupant's forward direction as 0 degrees, with a rotation angle to the right from that forward direction as a positive angle and a rotation angle to the left as a negative angle. The occupant's facial direction may be calculated two-dimensionally as horizontal movement, or three-dimensionally as horizontal and up-down movement. In this embodiment, an example is described in which the occupant's facial direction is calculated two-dimensionally as horizontal movement.

The control unit may detect the occupant's gaze direction. In this case, the control unit detects the pupil and corneal reflex from the captured image using image recognition processing. The gaze direction is then detected from the detected facial direction and the positional relationship between the detected pupil and corneal reflex. The gaze direction may be represented as a straight line originating from the eye point, which is the position of the occupant's eyes. The eye point may be specified, for example, as coordinates in three-dimensional space with a predetermined position on the vehicle as the origin. The eye point coordinates may be specified based on the correspondence between the eye position in the captured image and a position in three-dimensional space.

The display 14 displays information. The display 14 is installed inside the vehicle. Examples of the display 14 include a meter MID (Multi Information Display), a CID (Center Information Display), a passenger-side display, a HUD (Head-Up Display), an electronic mirror, and a large display. The display 14 is capable of partially controlling the brightness within the display area. For example, an organic EL display or the like may be used as the display 14.

The meter MID is a display placed in front of the driver's seat. The display area of the meter MID is set in the same position as the location of the meter MID. As an example, the meter MID may be configured to be provided on the meter panel. The CID is a display placed in the center cluster. The display area of the CID is set in the same position as the location of the CID. The passenger-side display is a display placed in front of the passenger seat. The display area of the passenger-side display is set in the same position as the location of the passenger-side display.

The HUD projects a display image formed on a display element based on image data acquired from the HCU 10 onto a projection area defined by a projection member in front of the driver's seat. This allows a virtual image of the display image to be superimposed on the external scenery in front of the vehicle and be displayed so that it can be seen. The projection area defined by the projection member in front of the driver's seat corresponds to the display area. The projection member onto which the HUD projects the display image may be the front windshield or a translucent combiner.

An electronic mirror is a display that sequentially displays images of the left, right, rear, and/or right rear of the vehicle captured by a perimeter monitoring camera. The perimeter monitoring camera is a camera that captures images of a specified area around the vehicle. Electronic mirrors that function as side mirrors may be configured to be located at the base of the left and right pillars on either side of the front windshield. Electronic mirrors that function as rearview mirrors may be configured to be located above the front windshield. The display area of the electronic mirror should be located in the same position as the electronic mirror.

An example of a large display is a pillar-to-pillar type display (hereinafter referred to as a PtoP display). A PtoP display is a display device whose display area extends between the left and right pillars located on both sides of the front windshield. A PtoP display can be realized by arranging multiple displays in a horizontal row on the instrument panel. A PtoP display can also be realized with a single display.

The HCU 10 is an electronic control device equipped with, for example, a processor, memory, I/O, and a bus connecting these. The HCU 10 controls the display on the display 14 by executing a control program stored in the memory. This HCU 10 corresponds to a vehicle display control device. The memory referred to here is a non-transitory tangible storage medium that non-temporarily stores computer-readable programs and data. The non-transitory tangible storage medium is realized by a semiconductor memory or a magnetic disk, for example. There may be multiple types of display 14 whose display is controlled by the HCU 10. Details of the HCU 10 are described below.

<General configuration of HCU 10>
Next, a schematic configuration of the HCU 10 will be described with reference to Figure 2. As shown in Figure 2, the HCU 10 includes an occupant state identification unit 101, an area identification unit 102, a vehicle state identification unit 103, and a display control unit 105 as functional blocks. Execution of the processing of each functional block of the HCU 10 by a computer corresponds to execution of a vehicle display control method. Some or all of the functions executed by the HCU 10 may be configured as hardware using one or more ICs or the like. Some or all of the functional blocks included in the HCU 10 may be realized by a combination of software execution by a processor and hardware components.

The occupant state identification unit 101 identifies the state of the occupant of the vehicle. The occupant state identification unit 101 may identify the presence of an occupant of the vehicle based on the detection results of the presence of an occupant of the vehicle by the interior camera 13. If there are multiple occupants in the vehicle, the occupant state identification unit 101 may identify the presence of multiple occupants. The occupant state identification unit 101 may also identify the type of occupant based on the position at which the occupant is recognized in the image captured by the interior camera 13. Occupant types include the driver, front passenger seat occupant, and rear seat occupant. The driver is an occupant sitting in the driver's seat. The front passenger seat occupant is an occupant sitting in the front passenger seat. The rear seat occupant is an occupant sitting in the rear seat. In the following description, the occupant state identification unit 101 will be described as distinguishing between the driver and the front passenger seat occupant, for example, as the type of occupant.

The occupant state identification unit 101 may identify the facial direction of the occupant of the vehicle from the detection result of the facial direction by the interior camera 13. The occupant state identification unit 101 may also identify the gaze direction of the occupant of the vehicle from the detection result of the gaze direction by the interior camera 13. The occupant state identification unit 101 may also be configured to perform part of the function of the control unit of the interior camera 13 described above. The occupant state identification unit 101 may detect the presence, facial direction, and gaze direction of the occupant based on the image captured by the interior camera 13.

Based on the results of detecting the vehicle's occupants, the area identification unit 102 identifies an area (hereinafter referred to as the visual recognition area) that is estimated to be the occupant's gaze. The area identification unit 102 may identify the visual recognition area based on the facial direction of the occupant identified by the occupant state identification unit 101. The visual recognition area may be a range that corresponds to the so-called effective field of view. The effective field of view is a range of approximately 20 degrees, 10 degrees to the left and 10 degrees to the right from the person's point of gaze. The effective field of view is a range in which the color and shape of an object can be recognized almost clearly. The range outside the effective field of view corresponds to peripheral vision. Peripheral vision is a range in which the color and shape of an object cannot be recognized clearly, but the movement of the object can be recognized. The visual recognition area may be a range that adds a margin to the effective field of view to take into account errors in identifying the visual recognition area based on the results of detecting the vehicle's occupants. Alternatively, the visual recognition area may be a range that adds a margin to the effective field of view to include a range of the effective field of view that anticipates movements in the facial direction and gaze direction. For example, it may be a range of several tens of degrees to the left and several tens of degrees to the right and several tens of degrees to the left and several tens of degrees from the person's point of gaze. The region identification unit 102 may identify the visual recognition region from the facial direction by utilizing a pre-associated correspondence between the facial direction and the visual recognition region. This correspondence may be a mathematical formula or a map. The region identification unit 102 may identify the visual recognition region based on the gaze direction of the occupant identified by the occupant state identification unit 101. In this case, the visual recognition region may be identified from the gaze direction by utilizing a pre-associated correspondence between the gaze direction and the visual recognition region. This processing by the region identification unit 102 corresponds to the region identification step.

The shape of the visible area identified by the area identification unit 102 may be elliptical or circular. The range of a person's effective field of vision on the display area of the display device 14 is elliptical. However, if the boundary for brightness control (described below) depending on whether or not an area is a visible area is elliptical, this may cause discomfort to the occupant compared to when the boundary is rectangular. Therefore, it is preferable that the shape of the visible area identified by the area identification unit 102 is rectangular. The following description will be given using an example where the shape of the visible area identified by the area identification unit 102 is rectangular. Furthermore, the area identification unit 102 may identify areas other than the visible area within the display area of the display device 14 as non-visual areas.

Now, the identification of areas by the area identification unit 102 will be explained using Figure 3. In the example of Figure 3, the case where the occupant is the driver Dr will be explained. The dashed-dotted line in Figure 3 indicates the front position of the driver Dr. DrAR in Figure 3 represents the area identified by the area identification unit 102 for the driver Dr. VAR in Figure 3 represents the visible area. NVAR in Figure 3 represents the non-visible area. LD in Figure 3 represents the luminance distribution within the display area of one display 14. As will be described later, as shown in Figure 3, in the visible area within the display area, the luminance is not reduced from the default, as indicated by A. On the other hand, in the non-visible area within the display area, the luminance is reduced from the default, as indicated by B.

When there are multiple occupants in the vehicle, the area identification unit 102 preferably identifies a visual area for each of the multiple occupants in the display area of a single display 14. The area identification unit 102 may determine whether there are multiple occupants in the vehicle from the presence of the occupants of the vehicle identified by the occupant state identification unit 101. Note that the area identification unit 102 may be configured not to identify visual areas and blurred areas for occupants other than the driver.

The vehicle state identification unit 103 identifies the state of the host vehicle. By monitoring the autonomous driving ECU 11, the vehicle state identification unit 103 identifies whether the host vehicle is being manually driven or autonomously driven. Note that the autonomous driving may be limited to autonomous driving of level 3 or higher, which does not require monitoring. The vehicle state identification unit 103 identifies whether the host vehicle is moving or stopped from the sensing information detected by the vehicle state sensor 12. For example, it may be possible to identify whether the host vehicle is moving or stopped from the vehicle speed. Alternatively, it may be possible to identify whether the host vehicle is moving or stopped from the shift position of the host vehicle.

The display control unit 104 controls the display on the display 14. The display control unit 104 controls the brightness within the display area of the display 14. The display control unit 104 is capable of partially controlling the brightness within the display area of the display 14. The display control unit 104 controls the brightness of an area of the display area of one display 14 that has been identified as a non-visible area by the area identification unit 102 so that it is lower than when it is identified as a visible area. For example, the brightness of the visible area is not lowered from the default brightness, whereas the brightness of the non-visible area is lowered below the default brightness. This makes it possible to reduce power consumption for the non-visible area of the display area of one display 14. The display control unit 104 may set the brightness of the non-visible area to 0, or may be configured not to lower the brightness of the non-visible area to 0. The brightness of the non-visible area is hereinafter referred to as the non-visible area brightness. The brightness of the visible area is hereinafter referred to as the visible area brightness.

The display control unit 104 reduces the brightness of an area that changes from a visible area to a non-visible area to the non-visible area brightness. Hereinafter, the area that changes from a visible area to a non-visible area is referred to as a non-visible transition area. The display control unit 104 returns the brightness of an area that changes from a non-visible area to a visible area to the visible area brightness. In other words, the display control unit 104 increases the brightness of an area that changes from a non-visible area to a visible area. Hereinafter, the area that changes from a non-visible area to a visible area is referred to as a visible transition area. Hereinafter, the change from a non-visible area to a visible area, and the change from a visible area to a non-visible area, are referred to as area changes.

The display control unit 104 controls the brightness of the non-visible transition area of the display area of one display device 14 so that the change in brightness in response to the area change is gradual. The area change here refers to the change from the visible area to the non-visible area. A gradual change here refers to a change that is slower than the standard change rate when transitioning from the non-visible area to the visible area. This makes it difficult for the occupant's peripheral vision to perceive sudden changes in brightness in the non-visible transition area. As a result, even if the screen of the display device 14 installed in the vehicle is enlarged, it is possible to reduce wasted power consumption of the display device 14 while minimizing discomfort to the occupant. On the other hand, the brightness of the visible transition area is changed using the standard change rate. This makes it possible to quickly restore brightness in response to the speed of movement of the visible area when transitioning from the non-visible area to the visible area. This reduces the discomfort caused by the occupant's gaze being directed at the display device while the brightness remains reduced. This processing by the display control unit 104 corresponds to the display control process.

The reference degree of change is, for example, the degree to which the brightness is changed to the target brightness in one frame. In the case of a non-visible transition area, the non-visible area brightness becomes the target brightness. In the case of a visible transition area, the visible area brightness becomes the target brightness. The frame here refers to the unit of switching between still images in the content displayed on the display device 14. The content may be, for example, an animation. For the visible area, it is sufficient to switch from the non-visible area brightness to the visible area brightness in one frame. On the other hand, for the non-visible transition area, the visible area brightness is not switched to the non-visible area brightness in one frame. For the non-visible transition area, it takes multiple frames to switch from the visible area brightness to the non-visible area brightness.

Here, an example of changes in luminance in response to changes in area will be described using Figures 4 to 7. Figure 4 is a diagram illustrating an example of changes in area depending on the facial direction of the occupant. Dra and Drb in Figure 4 represent the driver Dr with different facial directions. VAR in Figure 4 indicates the visible area. NVAR in Figure 4 indicates the non-visible area. DraAR in Figure 4 represents the area identified by the area identification unit 102 when the facial direction of the driver Dr is Dra. DrbAR in Figure 4 represents the area identified by the area identification unit 102 when the facial direction of the driver Dr is Drb. As shown in Figure 4, the visible area and non-visible area change depending on the facial direction of the occupant.

Figure 5 is a diagram illustrating an example of changes in luminance in response to changes in area. Figure 5 shows an example of changes in luminance in the display area in response to the area changes shown in Figure 4. NCLD in Figure 5 shows an example of changes in luminance when the control of the present disclosure is not performed. CLD in Figure 5 shows an example of changes in luminance when the control of the present disclosure is performed. NVTR in Figure 5 indicates the non-visible transition area. A in Figure 5 indicates the visible area luminance. B in Figure 5 indicates the non-visible area luminance. Figure 5 shows an example of changes in luminance in the display area in one frame when the driver Dr's facial orientation switches from Dra to Drb. As shown in Figure 5, when the control of the present disclosure is performed, the luminance of the non-visible transition area changes more slowly than when the control of the present disclosure is not performed.

Figure 6 is a diagram illustrating an example of changes in luminance in the non-visible transition region when the control of the present disclosure is not performed. Figure 7 is a diagram illustrating an example of changes in luminance in the non-visible transition region when the control of the present disclosure is performed. The horizontal axis in Figures 6 and 7 represents time. The vertical axis in Figures 6 and 7 represents luminance. As shown in Figure 6, when the control of the present disclosure is not performed, the luminance in the non-visible transition region changes suddenly. On the other hand, as shown in Figure 7, when the control of the present disclosure is performed, the luminance in the non-visible transition region changes gradually.

The display control unit 104 may control the change in luminance in response to area changes in the non-visible transition area of the driver of the vehicle so that the change is slower than the reference change rate. The display control unit 104 may control the change in luminance in response to area changes in the visible transition area of the driver of the vehicle so that the change is at the reference change rate. On the other hand, the display control unit 104 may control the change in luminance in both the non-visible transition area and the visible transition area of a passenger so that the change is slower than the reference change rate. The passenger may be a passenger in the front seat. The passenger may also include a passenger in the rear seat. If the luminance of the passenger's visible transition area is changed at the reference change rate when it is in an area not visible to the driver, the driver may feel uncomfortable. In contrast, the above configuration makes it possible to suppress such discomfort.

Here, using Figures 8 and 9, an example of changes in luminance with changes in area will be described when multiple occupants are the target. Figure 8 is a diagram illustrating an example of changes in area according to the facial orientation of each of multiple occupants. Dr in Figure 8 represents the driver. Psa and Psb in Figure 8 represent passenger Ps with different facial orientations, respectively. For convenience, Figure 8 shows an example where the facial orientation of driver Dr does not change. VARdr in Figure 8 represents the visual recognition area of driver Dr. VARps in Figure 8 represents the visual recognition area of passenger Ps. Dr/PsaAR in Figure 8 represents the area identified by area identification unit 102 when passenger Ps's facial orientation is Psa. Dr/PsbAR in Figure 8 represents the area identified by area identification unit 102 when passenger Ps's facial orientation is Psb. As described above, the facial orientation of driver Dr is assumed to be constant in Figure 8. As shown in Figure 8, the visible and non-visible areas change depending on the facial direction of passenger Ps. When the facial direction of the driver changes, the visible and non-visible areas also change depending on the facial direction of driver Dr, as explained using Figure 4.

Figure 9 is a diagram illustrating an example of a change in brightness in response to a change in area. Figure 9 shows an example of a change in brightness of the display area in response to the change in area shown in Figure 8. NCLD in Figure 9 shows an example of a change in brightness when the control of the present disclosure is not performed. CLD in Figure 9 shows an example of a change in brightness when the control of the present disclosure is performed. NVTR in Figure 9 shows a non-visible transition area. VTR in Figure 9 shows a visible transition area. Aps in Figure 9 indicates the visible area brightness for the visible area of passenger Ps. Adr in Figure 9 indicates the visible area brightness for the visible area of driver Dr. B in Figure 9 represents the non-visible area brightness. Figure 9 shows an example of a change in brightness of the display area in one frame when the facial direction of passenger Ps switches from Psa to Psb. As shown in Figure 9, when the control of the present disclosure is performed, the brightness of both the visible area and non-visible transition area for passenger Ps changes more slowly than when the control of the present disclosure is not performed.

When the host vehicle is moving, the display control unit 104 may control the non-visible transition region of the display area of one display 14 to change in luminance more slowly than the reference change degree. When the host vehicle is moving, the display control unit 104 may control the visible transition region of the passenger to change in luminance more slowly than the reference change degree. When the host vehicle is moving, the display control unit 104 may control the visible transition region of the driver to change in luminance at the reference change degree. On the other hand, when the host vehicle is stopped, the display control unit 104 may control both the non-visible transition region and the visible transition region of the display area of one display 14 to change at the reference change degree. This is because, when the vehicle is stopped, even if a sudden change in luminance in the non-visible transition region is detected in the peripheral vision of the occupant, it has little impact on driving. Note that the display control unit 104 may determine whether the host vehicle is moving or stopped from the results identified by the vehicle state identification unit 103.

When the host vehicle is being manually driven, the display control unit 104 may control the non-visual transition region of the display area of one display 14 to change in luminance more slowly than the reference change degree. When the host vehicle is being manually driven, the display control unit 104 may control the passenger's visible transition region to change in luminance more slowly than the reference change degree. When the host vehicle is being manually driven, the display control unit 104 may control the driver's visible transition region to change in luminance at the reference change degree. On the other hand, when the host vehicle is being autonomously driven, the display control unit 104 may control both the non-visual transition region and the visible transition region of the display area of one display 14 to change at the reference change degree. This is because, during autonomous driving, even if a sudden change in luminance in the non-visual transition region is detected in the occupant's peripheral vision, it has little impact on driving. The display control unit 104 may determine whether the host vehicle is being manually driven or autonomously driven from the results identified by the vehicle state identification unit 103.

When controlling the brightness change to be slower than the reference change rate, the display control unit 104 preferably controls the brightness change to be slower for each piece of content displayed in the display area. Examples of content displayed in the display area include navigation information, audio information, meter information, and entertainment information. Navigation information is, for example, a route guidance image. Audio information is, for example, an image related to the operation of audio equipment. Meter information is, for example, an image that schematically represents an instrument. Entertainment information is, for example, an image of a movie. As an example, when a piece of content moves out of the visible area, the display control unit 104 controls the brightness change to be slower for that piece of content. This is less likely to cause discomfort to the occupants than when the degree of brightness change varies for different parts of the same content.

<Brightness control related processing in HCU 10>
Next, an example of the flow of processing related to brightness control within the display area of one display 14 in the HCU 10 (hereinafter referred to as brightness control processing) will be described using the flowchart of Figure 10. The flowchart of Figure 10 may be configured to start, for example, when a power switch of the vehicle is turned on. The power switch is a switch for starting the internal combustion engine or the motor generator.

First, in step S1, the state of the driver and vehicle is identified. In S1, the occupant state identification unit 101 identifies the presence of an occupant, their facial orientation, etc. In S1, the vehicle state identification unit 103 identifies whether the vehicle is moving or stopped. In S1, the vehicle state identification unit 103 identifies whether the vehicle is being manually driven or automatically driven. In step S2, the area identification unit 102 identifies the visible area of the occupant based on the facial orientation identified in S1. Also, in S2, the area identification unit 102 identifies the display area outside the visible area as a non-visual area.

In step S3, the display control unit 104 performs brightness control on the display area of the display device 14 according to the area identified in S2. The display control unit 104 reduces the brightness of the non-visual transition area to the non-visual area brightness. The display control unit 104 increases the brightness of the visible transition area to the visible area brightness. As described above, the display control unit 104 may vary the brightness change of the non-visual transition area and the visible transition area depending on the type of occupant. As described above, the display control unit 104 may also vary the brightness change of the non-visual transition area and the visible transition area depending on whether the host vehicle is moving or stopped. As described above, the display control unit 104 may also vary the brightness change of the non-visual transition area and the visible transition area depending on whether the host vehicle is being driven autonomously or manually. As described above, the display control unit 104 may also change the brightness on a content-by-content basis.

In step S4, if it is time to end the brightness control-related processing (YES in S4), the brightness control-related processing ends. On the other hand, if it is not time to end the brightness control-related processing (NO in S4), the process returns to S1 and repeats. Examples of timing to end the brightness control-related processing include when the power switch is turned off.

The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also within the technical scope of the present disclosure. Furthermore, the control unit and method described in the present disclosure may be implemented by a special-purpose computer comprising a processor programmed to execute one or more functions embodied in a computer program. Alternatively, the device and method described in the present disclosure may be implemented by a special-purpose hardware logic circuit. Alternatively, the device and method described in the present disclosure may be implemented by one or more special-purpose computers configured by combining a processor that executes a computer program with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory tangible recording medium.

1 Vehicle system, 10 HCU (vehicle display control unit), 14 Display, 102 Area identification unit, 104 Display control unit

Claims (8)

A vehicle display control device is used in a vehicle and includes a display control unit (104) capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying unit (102) that sequentially specifies a visual recognition area, which is an area that is estimated to be a region that the occupant may be gazing at, based on the result of detecting the occupant of the vehicle;
The display control unit controls the luminance of a non-visual area, which is outside the area identified as the visible area by the area identification unit, of the display area of one of the display devices, to be lowered compared to when the area is identified as the visible area, in accordance with the movement of the visible area sequentially identified by the area identification unit, and controls the luminance change of an area that changes from the visible area to the non-visual area of the display area of one of the display devices to be slower than a reference degree of change when transitioning from the non-visual area to the visible area ,
the area specifying unit, when a plurality of occupants are present in the vehicle, sequentially specifies the visible area for each of the plurality of occupants in a display area of one of the display devices;
The display control unit controls, for the driver of the vehicle, the change in brightness in a region of the display area of one of the displays that changes from the visible region to the non-visible region so that the change is slower than the standard degree of change, and controls the change in brightness in a region that changes from the non-visible region to the visible region so that the change is at the standard degree of change, while for passengers other than the driver of the vehicle, the change in brightness in both the region of the display area of the display that changes from the visible region to the non-visible region and the region that changes from the non-visible region to the visible region is slower than the standard degree of change . A vehicle display control device is used in a vehicle and includes a display control unit (104) capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying unit (102) that sequentially specifies a visual recognition area, which is an area that is estimated to be an area that the occupant may be gazing at, based on the result of detecting the occupant of the vehicle;
The display control unit controls the luminance of a non-visual area, which is outside the area identified as the visible area by the area identification unit, of the display area of one of the display devices, to be lowered compared to when the area is identified as the visible area, in accordance with the movement of the visible area sequentially identified by the area identification unit, and controls the luminance change of an area that changes from the visible area to the non-visual area of the display area of one of the display devices to be slower than a reference degree of change when transitioning from the non-visual area to the visible area ,
The display control unit controls, when the vehicle is moving, the change in brightness of an area of the display area of one of the displays that changes from the visible area to the non-visible area so that the change is slower than the standard degree of change, and controls the change in brightness of an area that changes from the non-visible area to the visible area so that the change is at the standard degree of change, while when the vehicle is stopped, the display control unit controls both the area of the display area of the display that changes from the visible area to the non-visible area and the area that changes from the non-visible area to the visible area so that the change is at the standard degree of change . A vehicle display control device is used in a vehicle and includes a display control unit (104) capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying unit (102) that sequentially specifies a visual recognition area, which is an area that is estimated to be an area that the occupant may be gazing at, based on the result of detecting the occupant of the vehicle;
The display control unit controls the luminance of a non-visual area, which is outside the area identified as the visible area by the area identification unit, of the display area of one of the display devices, to be lowered compared to when the area is identified as the visible area, in accordance with the movement of the visible area sequentially identified by the area identification unit, and controls the luminance change of an area that changes from the visible area to the non-visual area of the display area of one of the display devices to be slower than a reference degree of change when transitioning from the non-visual area to the visible area ,
The vehicle is capable of switching between manual driving and automatic driving,
The display control unit controls, when the vehicle is being manually driven, the change in brightness of an area of the display area of one of the displays that changes from the visible area to the non-visible area so that the change is slower than the standard degree of change, and controls the change in brightness of an area that changes from the non-visible area to the visible area so that the change is at the standard degree of change, while when the vehicle is being automatically driven, the display control unit controls both the area of the display area of the display that changes from the visible area to the non-visible area and the area that changes from the non-visible area to the visible area so that the change is at the standard degree of change . A vehicle display control device is used in a vehicle and includes a display control unit (104) capable of partially controlling the brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying unit (102) that sequentially specifies a visual recognition area, which is an area that is estimated to be an area that the occupant may be gazing at, based on the result of detecting the occupant of the vehicle;
The display control unit controls the luminance of a non-visual area, which is outside the area identified as the visible area by the area identification unit, of the display area of one of the display devices, to be lowered compared to when the area is identified as the visible area, in accordance with the movement of the visible area sequentially identified by the area identification unit, and controls the luminance change of an area that changes from the visible area to the non-visual area of the display area of one of the display devices to be slower than a reference degree of change when transitioning from the non-visual area to the visible area ,
The display control unit controls the brightness of the display area of one of the displays to change more slowly than the reference degree of change in accordance with the movement of the visible area sequentially identified by the area identification unit, and controls the change to occur more slowly on a content-by-content basis in the display area . Executed by at least one processor,
A display control method for a vehicle, the method including a display control step for partially controlling brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying step of sequentially specifying a visual recognition area, which is an area that is estimated to be an area that the occupant may gaze at, based on a result of detecting the occupant of the vehicle;
In the display control step, in accordance with the movement of the visible area sequentially identified in the area identification step, the luminance of a non-visible area, which is outside the area identified as the visible area in the area identification step, of the display area of one of the display devices is controlled to be lowered compared to when the area is identified as the visible area, and for an area of the display area of one of the display devices that changes from the visible area to the non-visible area, the change in luminance corresponding to the change is controlled to be slower than a reference degree of change when transitioning from the non-visible area to the visible area ,
In the area specifying step, when a plurality of occupants are present in the vehicle, the visible areas of the display area of one of the display devices are sequentially specified for each of the plurality of occupants;
In the display control step, for the driver of the vehicle, the luminance change in a region of the display area of one of the displays that changes from the visible region to the non-visible region is controlled to be slower than the standard degree of change, and for the region that changes from the non-visible region to the visible region, the luminance change in the region that changes is controlled to be the standard degree of change, while for passengers other than the driver of the vehicle, the luminance change in both the region that changes from the visible region to the non-visible region and the region that changes from the non-visible region to the visible region is controlled to be slower than the standard degree of change . Executed by at least one processor,
A display control method for a vehicle, the method including a display control step for partially controlling brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying step of sequentially specifying a visual recognition area, which is an area that is estimated to be an area that the occupant may gaze at, based on a result of detecting the occupant of the vehicle;
In the display control step, in accordance with the movement of the visible area sequentially identified in the area identification step, the luminance of a non-visible area, which is outside the area identified as the visible area in the area identification step, of the display area of one of the display devices is controlled to be lowered compared to when the area is identified as the visible area, and for an area of the display area of one of the display devices that changes from the visible area to the non-visible area, the change in luminance corresponding to the change is controlled to be slower than a reference degree of change when transitioning from the non-visible area to the visible area ,
In the display control process, when the vehicle is moving, the change in brightness of an area of the display area of one of the displays that changes from the visible area to the non-visible area is controlled to be slower than the reference degree of change, and the change in brightness of an area that changes from the non-visible area to the visible area is controlled to change at the reference degree of change, while when the vehicle is stopped, the change in brightness of both the area of the display area of the display that changes from the visible area to the non-visible area and the area that changes from the non-visible area to the visible area is controlled to change at the reference degree of change . Executed by at least one processor,
A vehicle display control method used in a vehicle capable of switching between manual driving and automatic driving , the method including a display control step capable of partially controlling brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying step of sequentially specifying a visual recognition area, which is an area that is estimated to be an area that the occupant may gaze at, based on a result of detecting the occupant of the vehicle;
In the display control step, in accordance with the movement of the visible area sequentially identified in the area identification step, the luminance of a non-visible area, which is outside the area identified as the visible area in the area identification step, of the display area of one of the display devices is controlled to be lowered compared to when the area is identified as the visible area, and for an area of the display area of one of the display devices that changes from the visible area to the non-visible area, the change in luminance corresponding to the change is controlled to be slower than a reference degree of change when transitioning from the non-visible area to the visible area ,
In the display control process, when the vehicle is being manually driven, the luminance change in a region of the display area of one of the displays that changes from the visible region to the non-visible region is controlled to be slower than the reference degree of change, and the luminance change in a region that changes from the non-visible region to the visible region is controlled to change at the reference degree of change, while when the vehicle is being automatically driven, the luminance change in both the region of the display area of the display that changes from the visible region to the non-visible region and the region that changes from the non-visible region to the visible region is controlled to change at the reference degree of change . Executed by at least one processor,
A display control method for a vehicle, the method including a display control step for partially controlling brightness within a display area of a display device (14) mounted on the vehicle,
an area specifying step of sequentially specifying a visual recognition area, which is an area that is estimated to be an area that the occupant may gaze at, based on a result of detecting the occupant of the vehicle;
In the display control step, in accordance with the movement of the visible area sequentially identified in the area identification step, the luminance of a non-visible area, which is outside the area identified as the visible area in the area identification step, of the display area of one of the display devices is controlled to be lowered compared to when the area is identified as the visible area, and for an area of the display area of one of the display devices that changes from the visible area to the non-visible area, the change in luminance corresponding to the change is controlled to be slower than a reference degree of change when transitioning from the non-visible area to the visible area ,
In the display control process, when the brightness of the display area of one of the displays is controlled to change more slowly than the reference degree of change in accordance with the movement of the visible area sequentially identified in the area identification process, the display control method for a vehicle controls the change to occur more slowly on a content-by-content basis in the display area .