Vehicular light emitting device and vehicular light emission method

Abstract

Provided are a vehicular light emitting device and a vehicular light emission method capable of emitting image light to an appropriate position. A vehicular light emitting device (1000) comprises an image light emitting unit (100) that emits image light, and an imaging unit (200) that captures an image outside the vehicle, wherein, if the image outside the vehicle includes a plurality of straight-line components, the position to which the image light is emitted is adjusted on the basis of an intersection point on extension lines of the straight-line components.

Description

Vehicle light irradiation device and vehicle light irradiation method

[0001] The present invention relates to a light irradiation device and a light irradiation method for a vehicle, and more particularly to a light irradiation device and a light irradiation method for a vehicle that irradiate image light of a predetermined shape.

[0002] Conventionally, adaptive driving beam (ADB) light distribution control has been proposed, which uses a plurality of light-emitting diodes (LEDs) in a headlight to emit low beams or high beams as predetermined image light (see, for example, Patent Document 1). With this type of ADB light distribution control, it is possible to emit light onto a desired area, such as a road surface or a sign, while suppressing light irradiation onto other vehicles and pedestrians.

[0003] Also proposed is a head-up display (hereinafter referred to as HUD) device that projects an image onto the windshield of a vehicle to enable the driver to read information when viewing the area ahead of the vehicle (see, for example, Patent Documents 2 and 3). With such an HUD device, the driver can view an image light reflected by the windshield superimposed on the background ahead of the vehicle, thereby reducing the need to move one's line of sight while driving.

[0004] Such ADB headlights and HUD devices are vehicle light projection devices that project image light of a predetermined shape onto a predetermined position outside the vehicle or on the windshield. However, if the vehicle tilts due to vibration or other factors while driving, the projection position of the image light will deviate from the predetermined position. To solve this problem, it has been proposed to use auto-leveling technology that detects the tilt of the vehicle and corrects the projection position of the image light.

[0005] JP 2022-015772 A JP 2019-119248 A JP 2019-119262 A

[0006] However, conventional auto-leveling technology only detects the vehicle's inclination, making it difficult to project image light at the appropriate position in response to the vehicle's external conditions when there are changes in road gradient or curves.

[0007] SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned conventional problems, and has as its object to provide a vehicle light irradiation device and a vehicle light irradiation method that are capable of irradiating image light at an appropriate position.

[0008] In order to solve the above problem, the vehicle light irradiation device of the present invention comprises an image light irradiation unit that irradiates image light and an imaging unit that captures an image outside the vehicle, and is characterized in that when the image outside the vehicle contains multiple straight line components, the position at which the image light is irradiated is adjusted based on the intersection point on the extension lines of the straight line components.

[0009] In the vehicle light illumination device of the present invention, linear components are detected from the image of the outside of the vehicle captured by the imaging unit, and the illumination position of the image light is adjusted based on the intersection of the linear components, making it possible to illuminate the image light at an appropriate position in response to not only the inclination of the vehicle but also changes in the surrounding environment.

[0010] In one aspect of the present invention, the detection of the line components includes detecting the line components in a plurality of divided regions of the image of the outside of the vehicle, and calculating the intersection point for each of the divided regions.

[0011] In one aspect of the invention, when the intersection points differ depending on the divided regions, one of the intersection points is selected to adjust the irradiation position of the image light.

[0012] In one aspect of the present invention, the image light emitting unit is a headlight, and the image light is a low beam shaped by a cutoff line.

[0013] In one aspect of the present invention, the image light emitting unit is a head-up display that displays an image via a display unit.

[0014] In one aspect of the present invention, the straight line component is a road marking or a dividing line painted on a road.

[0015] In order to solve the above-mentioned problems, the vehicle light illumination method of the present invention is characterized by comprising an image light illumination process for illuminating image light, an imaging process for capturing an image outside the vehicle, and an image light adjustment process for adjusting the position at which the image light is illuminated based on the intersection point on the extension lines of the straight line components when the image outside the vehicle contains multiple straight line components.

[0016] The present invention can provide a vehicle light irradiation device and a vehicle light irradiation method that can irradiate image light at an appropriate position.

[0017] 5A is a schematic diagram illustrating the illumination of image lights L1 and L2 by a headlamp 4 and a head-up display 3 using a vehicle light illumination device 1000 according to the first embodiment. FIG. 6B is a block diagram illustrating the configuration of the vehicle light illumination device 1000 according to the first embodiment. FIG. 6C is a schematic diagram illustrating an example of an image 10 outside the vehicle captured by an imaging unit 200. FIG. 6D is a flowchart illustrating a vehicle light illumination method according to the first embodiment. FIG. 6D is a diagram illustrating the detection of lane markings 11 and 12 in an image 10 outside the vehicle and the calculation of an intersection 15, where FIG. 5A is an example photograph showing the image 10 outside the vehicle, FIG. 5B is a binarized image 10 outside the vehicle, and FIG. 5C is a diagram illustrating the results of a Hough transform. FIG. 6D is a schematic diagram illustrating image light adjustment in a head-up display 3, where FIG. 6A shows the relationship between the intersection 15 and a virtual image P before adjustment, and FIG. 6B shows the relationship between the intersection 15 and a virtual image P after adjustment. 7A and 7B are schematic diagrams illustrating image light adjustment in the headlamp 4, in which Fig. 7A shows the relationship between the intersection 15 and the image light L2 before adjustment, and Fig. 7B shows the relationship between the intersection 15 and the image light L2 after adjustment. Fig. 7B is a schematic diagram illustrating image processing according to a second embodiment. Fig. 7C is a flowchart illustrating a vehicle light irradiation method according to a second embodiment.

[0018] (First Embodiment) Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The same or equivalent components, members, and processes shown in each drawing will be assigned the same reference numerals, and redundant description will be omitted as appropriate. FIG. 1 is a schematic diagram illustrating the irradiation of image lights L1, L2 by a headlamp 4 and a head-up display 3 using a vehicle light irradiation device 1000 according to this embodiment. As shown in FIG. 1, a passenger (driver) 2 is on board a vehicle 1, and the vehicle 1 is provided with a windshield WS, a head-up display 3, a headlamp 4, and a control unit (not shown).

[0019] The head-up display 3 is a part that irradiates image light L1 of a predetermined image shape based on image information from a control unit. The specific configuration of the head-up display 3 is not limited, and a conventionally known display device such as a liquid crystal display device, an organic EL display device, or a combination of a laser light source and an optical modulation element can be used. The head-up display 3 is equipped with a free-form surface mirror or a reflecting mirror as a conventionally known projection optical unit, but is not shown in the figure.

[0020] The headlights 4 are components that emit image light L2 of a predetermined image shape. The specific configuration of the headlights 4 is not limited, but they need to be capable of emitting light shaped into a predetermined outline shape as the image light L2. An example of the image light L2 emitted from the headlights 4 is a low beam shaped by a cutoff line. Alternatively, the headlights 4 may use ADB light distribution control to emit light as an image of a predetermined shape.

[0021] The windshield WS is a portion provided in front of the driver's seat of the vehicle 1 that transmits visible light. The windshield WS, on the inside surface of the vehicle 1, reflects the image light L1 incident from the head-up display 3 toward the viewpoint of the occupant 2 and transmits light from outside the vehicle 1 toward the viewpoint, and therefore corresponds to the display unit in the present invention. While an example in which the windshield WS is used as the display unit is shown here, a combiner may be provided as a display unit separate from the windshield WS and reflect light from the head-up display 3 toward the viewpoint. Furthermore, the display unit is not limited to being located at the front of the vehicle 1, and may be located to the side or rear as long as it projects an image toward the viewpoint of the occupant 2.

[0022] The virtual image P is an image that is displayed as if it were formed in space when the image light L1 reflected by the windshield WS reaches the viewpoint (eyebox) of the occupant 2. The position at which the virtual image P is formed is determined by the angle at which light emitted from the head-up display 3 spreads as it travels toward the viewpoint after being reflected by the windshield WS. The content of the image projected as the virtual image P is not limited, but examples include auxiliary information related to driving, such as an image to call attention to an object, emergency information, a speed indicator, a volume indicator, and a driving direction guide. Furthermore, although FIG. 1 shows an example in which one image is projected as the virtual image P, multiple images may be projected as the virtual image P at different positions.

[0023] As shown in Fig. 1 , the head-up display 3 irradiates the windshield WS with image light L1, and the image light L1 reflected by the windshield WS reaches the viewpoint of the occupant 2. The occupant 2 visually recognizes a virtual image P through the windshield WS on an extension of the path of the image light L1. The headlights 4 irradiate the front of the vehicle 1 with image light L2. Therefore, the head-up display 3 and the headlights 4 each correspond to the image light irradiating unit in the present invention. Although Fig. 1 shows the head-up display 3 and the headlights 4, conventionally known vehicle lighting devices such as a road surface drawing device that draws an image on the road surface may also be used.

[0024] 2 is a block diagram showing the configuration of the vehicle light irradiation device 1000 according to this embodiment. As shown in FIG. 2, the vehicle light irradiation device 1000 includes an image light irradiation unit 100, an imaging unit 200, an image processing unit 300, and an irradiation position adjustment unit 400. The vehicle light irradiation device 1000 also includes a control unit (not shown) that is connected to each unit so as to be able to communicate information with each unit and control each unit. The configuration of the control unit is not limited, but examples include a CPU (Central Processing Unit) for performing information processing, a memory device, a recording medium, an information communication device, and the like. The control unit controls the operation of each unit according to a predetermined program.

[0025] The image light irradiating unit 100 is a part that irradiates light shaped into a predetermined shape as image light L1, L2. When the image light irradiating unit 100 is a head-up display 3, for example, the image light L1 is light irradiated through a windshield WS (display unit). When the image light irradiating unit 100 is a headlight 4, for example, the image light L2 is a low beam shaped by a cutoff line. The configuration of the image light irradiating unit 100 for shaping the image light L1, L2 is not limited, and may be a configuration that irradiates an image displayed on a display device with a backlight, a configuration that selectively controls the lighting of LEDs arranged in a matrix, a configuration that blocks part of the light irradiated from a light source with a shade, a configuration that controls the reflection direction of laser light, or the like. Furthermore, the image light irradiating unit 100 is capable of adjusting the position at which the image light L1, L2 is irradiated by an irradiation position adjusting unit 400, which will be described later.

[0026] The imaging unit 200 is mounted on the vehicle 1 and captures images of the exterior of the vehicle 1. The specific configuration of the imaging unit 200 is not limited, and a conventionally known CCD (Charge Coupled Device) camera, a CMOS (Complementary Metal Oxide Semiconductor) camera, or the like may be used. The imaging unit 200 may also be a monochrome camera that captures monochrome images, or a color camera that captures color images. The location at which the imaging unit 200 is provided is not limited, and the imaging unit 200 may be provided on the upper part of the windshield WS when capturing an image of the area ahead of the vehicle 1. Alternatively, a camera for an advanced driver-assistance system (ADAS) mounted on the vehicle 1 may be used as the imaging unit 200. The image of the exterior of the vehicle captured by the imaging unit 200 is transmitted to the image processing unit 300.

[0027] The image processing unit 300 is a part that acquires an image of the outside of the vehicle captured by the imaging unit 200 and processes information in the image. The image processing unit 300 is a function realized by a control unit provided in the vehicle light irradiation device 1000 executing a predetermined program. More specifically, the image processing unit 300 detects straight line components in the image and calculates intersection points on extensions of the straight line components. There are no limitations on the method for detecting straight line components in the image, but a conventionally known Hough transform or the like can be used. The image processing in the image processing unit 300 will be described in detail later. The results of the detection of the straight line components and the calculation of the intersection points in the image processing unit 300 are transmitted to the irradiation position adjustment unit 400.

[0028] The irradiation position adjustment unit 400 is a part that adjusts the irradiation positions of the image lights L1 and L2 from the image light irradiation unit 100 based on the detection results of the straight line components and the calculation results of the intersection points by the image processing unit 300. The irradiation position adjustment unit 400 is a function that is realized by a predetermined program being executed by a control unit provided in the vehicle light irradiation device 1000. The specific configuration of the irradiation position adjustment unit 400 is not limited, and for example, a configuration that uses a swivel actuator that mechanically adjusts the direction of the image light irradiation unit 100, a configuration that changes the image display position in the image light irradiation unit 100, a configuration that changes the irradiation direction of the image lights L1 and L2 using a lens or a reflecting mirror, or the like can be used.

[0029] FIG. 3 is a schematic diagram showing an example of an image 10 outside the vehicle captured by the imaging unit 200. FIG. 3 shows an example of the image 10 outside the vehicle when the imaging unit 200 captures an image of the area in front of the vehicle 1 at night. The image 10 outside the vehicle is not limited to the area in front of the vehicle 1, but may be an area behind or to the side of the vehicle 1. Although FIG. 3 shows an example of a nighttime image, the image 10 outside the vehicle may be a daytime image. As shown in FIG. 3, the image 10 outside the vehicle includes the road surface, scenery outside the roadway, distant scenery, space above the vehicle 1, and the like. Furthermore, the image 10 outside the vehicle shown in FIG. 3 includes a plurality of linearly-shaped captured objects. Examples of linearly-shaped captured objects include guardrails, road markings, dividing lines, trees, and road signposts.

[0030] In this embodiment, a linear component included in the image 10 outside the vehicle is detected in order to determine the positions to which the image lights L1 and L2 are irradiated. To this end, it is preferable that the reference linear component is an imaged object that reflects as much as possible information about the road surface on which the vehicle 1 is traveling. Furthermore, if the imaged object is associated with the road surface, the image lights L1 and L2 can be irradiated in accordance with the environment outside the vehicle even if the vehicle 1 tilts due to vibration and the relative positional relationship between the vehicle 1 and the road surface changes.

[0031] The straight line components detected from the image 10 outside the vehicle are preferably imaged objects fixed on the road, such as guardrails, road markings, dividing lines 11 and 12, and road sign posts. Guardrails, road markings, and dividing lines 11 and 12 are more preferable because they are provided along the direction of travel of the vehicle 1. Furthermore, road markings or dividing lines 11 and 12 are most preferable because they are likely to be provided on the road and are drawn based on standards set forth in laws and regulations.

[0032] 3, on the road surface on which the vehicle 1 is traveling, straight line components extending from a position closer to the vehicle 1 to a position farther away are detected as the lane markings 11 and 12. Furthermore, in the image 10 of the exterior of the vehicle, the lane markings 11 and 12 are drawn only on the road surface. Therefore, in the vehicle light irradiation device 1000 of this embodiment, straight lines 13 and 14 are assumed to be extensions of the lane markings 11 and 12, and the position where the straight lines 13 and 14 intersect is calculated as the intersection point 15.

[0033] The straight line drawn in the left-right direction in FIG. 3 is an assumed horizon line. When the road surface on which the vehicle 1 is traveling is horizontal and straight, the intersection 15 coincides with the vanishing point of the lines 13 and 14. When the road surface on which the vehicle 1 is traveling is inclined or curved, the intersection 15 differs from the vanishing point of the lines 13 and 14. In either case, the intersection 15 is a point calculated based on the lane markings 11 and 12, and is likely to be the position where the vehicle 1 should arrive in the near future, reflecting the conditions of the road surface on which the vehicle 1 is traveling. Furthermore, the intersection 15 is a position that is likely to be visible to the passenger (driver) 2 as the direction of travel of the vehicle 1. Therefore, by adjusting the irradiation position of the image light L1 and L2 based on the intersection 15 of the lines 13 and 14, it is possible to irradiate the image light L1 and L2 at an appropriate position in response to not only the inclination of the vehicle 1 but also changes in the surrounding environment.

[0034] 4 is a flowchart illustrating the vehicle light irradiation method according to this embodiment. In the vehicle light irradiation device 1000, the control unit reads a predetermined program from a recording medium, and each unit operates in accordance with the program, thereby executing the vehicle light irradiation method.

[0035] First, in the image light irradiation process of step S1, image light L1 is irradiated from the head-up display 3, which is the image light irradiation unit 100, and image light L2 is irradiated from the headlights 4. As an example, the image light L1 includes auxiliary information related to driving, such as vehicle speed, and the image light L2 is a low beam with a cut-off line. When the image light irradiation process is performed for the first time, the image lights L1 and L2 may be irradiated at a predetermined initial state position, or the image lights L1 and L2 may be irradiated at a pre-recorded irradiation position at the time of the previous end. While the image light irradiation process is continuously performed, the process proceeds to step S2.

[0036] Next, in the imaging step of step S2, an image 10 of the outside of the vehicle is captured using the imaging unit 200. Here, the position and mounting angle of the imaging unit 200 on the vehicle 1 are predetermined, and the angle of view of the imaging unit 200 is also known in advance, so the relative positional relationship between the coordinates in the image 10 of the outside of the vehicle and the vehicle 1 is known. The imaging unit 200 transmits the captured image 10 of the outside of the vehicle to the image processing unit 300, and the process proceeds to step S3.

[0037] Next, in the line detection process of step S3, the image processing unit 300 detects line components contained in the exterior image 10. Because the exterior image 10 contains multiple line components, specific line components are extracted to determine the irradiation positions of the image lights L1 and L2. As an example, line components of road markings or lane markings 11 and 12 contained in the exterior image 10 are extracted and detected. While the method for detecting specific line components is not limited, for example, a Hough transform can be performed on the exterior image 10 to detect line components extending from near to far from the vehicle 1 as lane markings 11 and 12. In particular, a line extending from an area located directly in front of the vehicle 1 within a range slightly wider than the width of the vehicle 1 toward the center of the image 10 can be estimated to be lane markings 11 and 12 based on its position and angle. While an example of extracting two lane markings 11 and 12 as specific line components is shown here, a larger number of lines may also be extracted.

[0038] Furthermore, when executing the line detection process for the second or subsequent times, it is preferable to continuously trace and extract the lane markings 11, 12 extracted during the previous execution. The method for tracing the specific line components is not limited, but for example, the lane markings 11, 12 can be extracted by applying a predetermined low-pass filter or Kalman filter to the image 10. More specifically, a uniform motion model may be used as the state transition matrix of the Kalman filter, and the Hough-transformed values ​​of θ and ρ may be predicted using the following Equations 1 and 2: (Equation 1) θ(k) = θ(k-1) + Δθ(k-1)Δt (Equation 2) ρ(k) = ρ(k-1) + Δρ(k-1)Δt After the image processing unit 300 extracts the specific line components, the process proceeds to step S4.

[0039] Next, in the intersection detection process of step S4, the image processing unit 300 extends the specific line components extracted in the line detection process to create lines 13 and 14, detects the position where the lines 13 and 14 intersect as an intersection 15, and calculates the coordinates in the vehicle exterior image 10. As described above, the relative positional relationship between the coordinates in the vehicle exterior image 10 and the vehicle 1 is known, so the relative positional relationship between the coordinates of the intersection 15 and the vehicle 1 can also be determined. Furthermore, as described above, the intersection 15 in the vehicle exterior image 10 is a position corresponding to the external environment of the vehicle 1, and therefore functions as a reference position in the external environment regardless of the inclination of the vehicle 1. Therefore, determining the coordinates in the vehicle exterior image 10 based on the coordinates of the intersection 15 determines the relative positional relationship between the reference position in the external environment and the vehicle 1. After the image processing unit 300 calculates the coordinates of the intersection 15, the process proceeds to step S5.

[0040] Next, in the image light adjustment step of step S5, the irradiation position adjustment unit 400 adjusts the irradiation positions of the image light L1 and L2 emitted from the image light irradiation unit 100 based on the coordinates of the intersection 15 calculated in the intersection detection step. The method for adjusting the irradiation positions of the image light L1 and L2 is not limited, but for example, the irradiation positions can be adjusted so that the relative positional relationship with the intersection 15 satisfies predetermined conditions. More specifically, the display position of the image can be shifted so that the image light L1 and L2 are irradiated at coordinates that are a predetermined distance from the intersection 15. Here, the adjustment of the irradiation positions of the image light L1 and L2 may be performed by slowly varying the irradiation positions with a predetermined time constant. Alternatively, the irradiation positions may be adjusted only when the coordinates of the intersection 15 have changed beyond a predetermined threshold. After the irradiation position adjustment unit 400 adjusts the irradiation positions of the image light L1 and L2, the process returns to step S1.

[0041] Next, the extraction of straight line components and the calculation of intersection points 15 in image processing unit 300 will be described in more detail using FIG. 5. FIG. 5 illustrates the detection of lane markings 11, 12 in an image 10 of the exterior of the vehicle and the calculation of intersection points 15. FIG. 5(a) is an example photograph showing image 10 of the exterior of the vehicle, FIG. 5(b) shows the binarized image 10 of the exterior of the vehicle, and FIG. 5(c) is a diagram illustrating the results of the Hough transform. As shown in FIG. 5(a), image 10 of the exterior of the vehicle captured by imaging unit 200 in the imaging process includes the road surface and scenery outside the road. In addition, low beam light L2 emitted from headlights 4 is irradiated onto the road surface and scenery outside the road.

[0042] As shown in FIG. 5( b), in the line detection process, the image processing unit 300 converts the image 10 of the exterior of the vehicle shown in FIG. 5( a) into a black-and-white binary image. At this time, it is preferable to set the threshold value used for the black-and-white conversion to an appropriate range so that the lane markings 11 and 12 are clearly visible. As shown in FIG. 5( c), when the black-and-white binary image is subjected to a Hough transform and peak detection is performed, the multiple line components y = ax + b contained in the black-and-white binary image are converted into points (ρ, θ) in Hough space. At this time, the curves plotted in Hough space shown in FIG. 5( c) correspond to the line components in the image 10, and therefore the point where the plots intersect in Hough space corresponds to the intersection 15 of the lines 13 and 14. This allows the image processing unit 300 to extract the line components and calculate the coordinates of the intersection 15.

[0043] Next, the adjustment of the projection position of the image light L1 by the projection position adjustment unit 400 will be described in more detail using FIG. 6 . FIG. 6 is a schematic diagram illustrating image light adjustment in the head-up display 3, where FIG. 6( a) shows the relationship between the intersection 15 and the virtual image P before adjustment, and FIG. 6( b) shows the relationship between the intersection 15 and the virtual image P after adjustment. After the image processing unit 300 calculates the coordinates of the intersection 15 from the image 10 in the intersection detection process, the projection position adjustment unit 400 sets the projection position of the virtual image P to a predetermined position. In the example shown in FIG. 6( a), the projection position of the image light L1 from the image light projection unit 100 is set so that the virtual image P is projected a distance d downward from the intersection 15. FIG. 6( b) assumes a case where the tilt angle of the vehicle 1 has changed. In FIGS. 6( a) and 6( b), the projection position of the virtual image P is shown as a position distance d downward from the intersection 15, but the direction and distance are not limited.

[0044] Assume that while the vehicle light irradiation device 1000 repeatedly executes the vehicle light irradiation method shown in FIG. 4 , the front of the vehicle 1 rises and the rear of the vehicle falls (tilts backward), causing the imaging range of the vehicle exterior image 10 captured by the imaging unit 200 to change by Δh. In this case, as shown in FIG. 6B , the coordinates of the intersection 15 in the vehicle exterior image 10 also change by a distance corresponding to Δh. In this case, the irradiation position adjustment unit 400 also sets the irradiation position of the image light L1 from the image light irradiation unit 100 so that the virtual image P is projected a distance d downward from the intersection 15. Therefore, the image light L1 that projects the virtual image P is irradiated onto an area that has moved downward by Δh from the position where the original virtual image P′ was irradiated before the vehicle 1 tilted, in the coordinates in the vehicle exterior image 10.

[0045] 6(a) and 6(b) indicate the upper end position of the image light L1 that projects the virtual image P, but the relative positional relationship with the intersection point 15 does not change. Therefore, even if the vehicle 1 tilts, the relative positional relationship between the environment outside the vehicle that the occupant 2 sees through the windshield WS and the imaging position of the virtual image P does not change, and the image light L1 can be irradiated to an appropriate position in response to changes in the surrounding environment.

[0046] Next, the adjustment of the irradiation position of the image light L2 by the irradiation position adjustment unit 400 will be described in more detail using FIG. 7 . FIG. 7 is a schematic diagram illustrating image light adjustment by the headlamp 4, where FIG. 7( a) shows the relationship between the intersection 15 and the image light L2 before adjustment, and FIG. 7( b) shows the relationship between the intersection 15 and the image light L2 after adjustment. After the image processing unit 300 calculates the coordinates of the intersection 15 from the image 10 in the intersection detection process, the irradiation position adjustment unit 400 sets the irradiation position of the low beam, which is the image light L2, to a predetermined position. In the example shown in FIG. 7( a), the irradiation position of the image light L2 from the image light irradiation unit 100 is set so that the elbow point in the low beam cutoff line is the intersection 15. FIG. 7( b) illustrates a case where the tilt angle of the vehicle 1 has changed.

[0047] Assume that the front of the vehicle 1 rises and the rear falls (tilts backward), causing the imaging range of the vehicle exterior image 10 captured by the imaging unit 200 to change by Δh. In this case, the coordinates of the intersection point 15 in the vehicle exterior image 10 also change by a distance corresponding to Δh, as shown in FIG. 7B . In this case, the irradiation position adjustment unit 400 also sets the irradiation position of the image light L2 from the image light irradiation unit 100 so that the elbow point of the cutoff line coincides with the intersection point 15. Therefore, in the coordinates in the vehicle exterior image 10, the image light L2 that projects the image light L2 is irradiated onto an area that has moved downward by Δh from the position where the image light L2' was irradiated before the vehicle 1 tilted.

[0048] Therefore, even if the vehicle 1 tilts, the relative positional relationship between the environment outside the vehicle that the passenger 2 sees through the windshield WS and the imaging position of the virtual image P does not change, and the image light L2 can be irradiated to an appropriate position according to changes in the surrounding environment.

[0049] As described above, in the vehicle light illumination device 1000 and vehicle light illumination method of this embodiment, the components of the straight lines 13 and 14 are detected from the image 10 outside the vehicle captured by the imaging unit 200, and the illumination positions of the image lights L1 and L2 are adjusted based on the intersection 15 of the straight line 13 and 14 components, so that it is possible to illuminate the image lights L1 and L2 at appropriate positions in accordance with not only the inclination of the vehicle 1 but also changes in the surrounding environment.

[0050] Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG. 8. Description of content that overlaps with the first embodiment will be omitted. FIG. 8 is a schematic diagram illustrating image processing according to this embodiment. This embodiment differs from the first embodiment in that an image 10 of the exterior of the vehicle is divided into a plurality of regions, and line components are detected in each divided region.

[0051] As shown in FIG. 8 , the image 10 of the outside of the vehicle captured by the imaging unit 200 is divided into a near region R1 located near the vehicle 1 on the road surface and a far region R2 located farther away than the near region R1. Here, an example in which the image is divided into two regions, the near region R1 and the far region R2, is shown, but the image may be divided into more regions. Furthermore, the division of the regions is not limited to the road surface. Furthermore, while FIG. 8 shows an example in which the near region R1 and the far region R2 are regions with different heights across the entire width of the image 10, the shape of the division is not limited.

[0052] In this embodiment, a straight line component is detected within the near region R1 to calculate an intersection point 15a (not shown). Also, a straight line component is detected within the far region R2 to calculate an intersection point 15b (not shown). Here, since the near region R1 is an area located near the vehicle 1, the road surface included in the near region R1 has a large influence on the current course and inclination of the vehicle 1. Also, since the far region R2 is an area located far from the vehicle 1, the road surface included in the far region R2 has a large influence on the course and inclination of the vehicle 1 in the near future. Therefore, if the intersection points 15a and 15b of the near region R1 and the far region R2, which are multiple divided regions, are different, it is preferable to select one of the multiple intersection points 15a and 15b and adjust the irradiation positions of the image light L1 and L2.

[0053] Therefore, when the irradiation position adjustment unit 400 adjusts the irradiation positions of the image lights L1 and L2 based on the intersection 15a calculated from the near region R1, it is possible to perform irradiation that is suited to the current situation of the vehicle 1. Furthermore, when the irradiation position adjustment unit 400 adjusts the irradiation positions of the image lights L1 and L2 based on the intersection 15b calculated from the far region R2, it is possible to predict the situation of the vehicle 1 in the near future and perform corresponding irradiation.

[0054] 9 is a flowchart illustrating a vehicle light irradiation method according to this embodiment. First, in an image light irradiation step of step S11, image light L1 is irradiated from the head-up display 3, which is the image light irradiation unit 100, and image light L2 is irradiated from the headlights 4. While the image light irradiation step is continuously performed, the process proceeds to step S12. Next, in an imaging step of step S12, an image 10 outside the vehicle is captured using the imaging unit 200. The imaging unit 200 transmits the captured image 10 outside the vehicle to the image processing unit 300, and the process proceeds to step S13.

[0055] Next, in the line detection step of step S13, the image processing unit 300 detects line components contained in each of the near region R1 and the far region R2 in the vehicle exterior image 10. After the image processing unit 300 extracts the specific line components, the process proceeds to step S14.

[0056] Next, in the intersection detection step of step S14, the image processing unit 300 extends specific line components in each of the near region R1 and the far region R2 extracted in the line detection step to create lines 13 and 14. The image processing unit 300 also detects the positions where the lines 13 and 14 intersect as intersections 15a and 15b, and calculates the coordinates of these intersections in the image 10 outside the vehicle. After the image processing unit 300 calculates the coordinates of the intersections 15a and 15b, the process proceeds to step S15.

[0057] Next, in the intersection determination process of step S15, the image processing unit 300 determines whether the coordinates of the intersections 15a and 15b match, and if they match, it decides to use the intersections 15a and 15b to adjust the positions of the image lights L1 and L2 and proceeds to step S17, but if they do not match, it proceeds to step S16.

[0058] In the road surface change estimation process of step S16, the image processing unit 300 estimates changes in the road surface while the vehicle 1 is traveling from the difference in coordinates of the intersections 15a and 15b, and determines which of the intersections 15a and 15b to use for adjusting the irradiation positions of the image lights L1 and L2. As a specific example, if the difference in height between the intersections 15a and 15b is greater than a threshold and a large change in the inclination angle of the road surface is expected, the image processing unit 300 determines to use the intersection 15b in the far region R2. As another example, if the difference in width between the intersections 15a and 15b is greater than a threshold and a curved road surface is expected, the image processing unit 300 determines to use the intersection 15b in the far region R2. As yet another example, if the difference in height and width between the intersections 15a and 15b is smaller than a threshold and a small change in the road surface is expected, the image processing unit 300 determines to use the intersection 15a in the near region R1. After the image processing unit 300 determines which of the multiple intersections 15a and 15b is to be used for adjusting the positions of the image lights L1 and L2, the process proceeds to step S17.

[0059] In the image light adjustment process of step S17, the irradiation position adjustment unit 400 adjusts the irradiation positions of the image light L1, L2 irradiated from the image light irradiation unit 100 based on the coordinates of the intersection 15a or 15b determined in step S15 or step S16. After the irradiation position adjustment unit 400 adjusts the irradiation positions of the image light L1, L2, the process proceeds again to step S11.

[0060] As described above, in the vehicle light irradiation device 1000 and vehicle light irradiation method of this embodiment, straight line components are detected in each of multiple divided regions (near region R1, far region R2) of the image 10 outside the vehicle, and intersections 15a and 15b are calculated for each divided region, making it possible to irradiate image light L1 and L2 at more appropriate positions in response to changes in the surrounding environment.

[0061] The present invention 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 included in the technical scope of the present invention.

[0062] This international application claims priority based on Japanese Patent Application No. 2023-119525, filed on July 22, 2023, the entire contents of which are incorporated herein by reference.

[0063] The above descriptions of specific embodiments of the present invention have been presented for purposes of illustration. They are not intended to be exhaustive or to limit the invention to the precise forms described. Numerous modifications and variations will be apparent to those skilled in the art in light of the above description.

[0064] DESCRIPTION OF SYMBOLS 1000... Vehicle light irradiation device 100... Image light irradiation unit 200... Imaging unit 300... Image processing unit 400... Illumination position adjustment unit 1... Vehicle 2... Passenger 3... Head-up display 4... Headlight 10... Image 11, 12... Marking line 13, 14... Straight line 15, 15a, 15b... Intersection L1, L2... Image light R1... Near region R2... Far region

Claims

1. A light illumination device for a vehicle comprising an image light illumination unit that illuminates image light and an imaging unit that captures an image outside the vehicle, and characterized in that when the image outside the vehicle contains multiple straight line components, the position at which the image light is illuminated is adjusted based on the intersection point on the extension lines of the straight line components.

2. A light irradiation device for a vehicle as described in claim 1, characterized in that the detection of the straight line components comprises detecting the straight line components in a plurality of divided areas of the image outside the vehicle, and calculating the intersection point for each of the divided areas.

3. A vehicle light irradiation device as described in claim 2, characterized in that, when the intersection points differ depending on the divided areas, one of the multiple intersection points is selected to adjust the irradiation position of the image light.

4. A light irradiation device for a vehicle according to claim 1, characterized in that the image light irradiation unit is a headlight, and the image light is a low beam formed by a cut-off line.

5. A light irradiation device for a vehicle according to claim 1, characterized in that the image light irradiation unit is a head-up display that displays an image via a display unit.

6. A light irradiation device for a vehicle according to any one of claims 1 to 5, characterized in that the straight line component is a road marking or a dividing line painted on a road.

7. A light illumination method for a vehicle comprising: an image light illumination process for illuminating image light; an imaging process for capturing an image outside the vehicle; and an image light adjustment process for adjusting the position at which the image light is illuminated based on the intersection point on the extension lines of the straight line components when the image outside the vehicle contains multiple straight line components.

Images