Lighting device for vehicle

Abstract

A vehicle lighting device (1) is provided with: a low-beam irradiation unit (low-beam unit (7)) that illuminates a lower irradiation region (low-beam irradiation region (11)) on the lower side in front of a vehicle; a high-beam irradiation unit (high-beam unit (6)) that illuminates an upper irradiation region (high-beam irradiation region (10)) that is located on the center side in the vehicle width direction and above the lower irradiation region (11); and a variable pattern irradiation unit (projector unit (8)) that illuminates a lateral upper irradiation region (right pattern irradiation region (12)) that is a lateral region that is further outward in the vehicle width direction than the upper irradiation region (10) and further upward than the lower irradiation region (11), in such a manner that the irradiation pattern can be varied, the lateral upper irradiation region (right pattern irradiation region (12)) being a lateral region that is further outward in the vehicle width direction than the upper irradiation region (10) and further upward than the lower irradiation region (11). In one aspect, the variable pattern irradiation unit (8) changes the irradiation pattern by either the first irradiation pattern (15) or the second irradiation pattern (16) in accordance with whether or not the high beam irradiation unit (6) is lit. Therefore, even under severe conditions such as night and rainy days, seeing missing of pedestrians by a driver can be improved.

Description

Technical Field

[0001] The invention relates to a lighting device for a vehicle. Background Art

[0002] As a vehicle lighting device, a device has been proposed that suppresses glare on pedestrians and enables the driver to see pedestrians clearly (for example, refer to Patent Document 1). In the vehicle lighting device of Patent Document 1, the lighting amount for the upper body of the pedestrian is reduced (to 0) according to the distance to the pedestrian acquired by the pedestrian detection sensor.

[0003] [Prior Technical Literature]

[0004] (Patent Document)

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-184614 Summary of the invention

[0006] [Problems to be solved by the invention]

[0007] However, in the technology of Patent Document 1, although the glare on the pedestrian side is suppressed, there is a risk that the visibility of the pedestrian from the driver's side is insufficient.

[0008] The present invention is made in view of the above situation, and its purpose is to provide a vehicle lighting device that can improve the driver's omission of pedestrians even under adverse conditions such as nighttime and rainy days. In addition, its purpose is to further improve traffic safety and contribute to the development of sustainable transportation systems.

[0009] [Technical means to solve the problem]

[0010] (1) A lighting device for a vehicle, comprising: a low beam irradiation portion (e.g., a low beam unit 7 described below), which illuminates a lower irradiation area on the lower side in front of the vehicle (e.g., a low beam irradiation area 11 described below); a high beam irradiation portion (e.g., a high beam unit 6 described below), which illuminates an upper irradiation area that is higher than the aforementioned lower irradiation area and located on the center side in the vehicle width direction (e.g., a high beam irradiation area 10 described below); and a variable pattern irradiation portion (e.g., a projector unit 8 described below), which illuminates a side upper irradiation area (e.g., a right side pattern irradiation area 12 described below) in a form that can change the irradiation pattern, wherein the side upper irradiation area (e.g., the right side pattern irradiation area 12 described below) is a side area that is higher than the aforementioned upper irradiation area in the vehicle width direction and higher than the aforementioned lower irradiation area.

[0011] (2) The vehicle lighting device according to (1), wherein the variable pattern irradiation unit changes the form of the irradiation pattern depending on whether the high beam irradiation unit is turned on or not.

[0012] (3) A vehicle lighting device according to (1) or (2), wherein the variable pattern illumination unit is capable of switching between at least two illumination patterns, namely, a first illumination pattern (for example, the first illumination pattern 15 described below) and a second illumination pattern (for example, the second illumination pattern 16 described below), and switching to any one of the illumination patterns according to the driving condition of the vehicle, wherein the first illumination pattern (for example, the first illumination pattern 15 described below) is an alternating repetition of bright areas (for example, the bright area 13 described below) and dark areas (for example, the dark area 14 described below), and the second illumination pattern (for example, the second illumination pattern 16 described below) is a single bright area.

[0013] (Effects of the Invention)

[0014] In the vehicle lighting device of (1), by illuminating light with an illumination pattern of alternating bright and dark areas from a variable pattern illumination unit, the driver can easily recognize the presence of pedestrians on the roadside by utilizing the human visual characteristics. Even under adverse conditions such as at night and in rainy days, the driver's omission of pedestrians can be improved. On the other hand, in situations where the possibility of pedestrians on the roadside is extremely low, such as on highways, the illumination pattern from the variable pattern illumination unit can be changed to improve visibility in the distant field of view. In addition, traffic safety is further improved and a contribution is made to the development of sustainable transportation systems.

[0015] In the vehicle lighting device of (2), the configuration of the illumination pattern of the variable pattern illumination unit can be reduced to avoid overlapping of the illumination areas of the high beam illumination unit and the variable pattern illumination unit, thereby reducing power consumption of the variable pattern illumination unit.

[0016] In the vehicle lighting device of (3), for example, when driving on a single-lane road, if the variable pattern illumination unit emits light of a first illumination pattern that alternately repeats bright areas and dark areas, the driver can easily recognize the presence of pedestrians by utilizing human visual characteristics. On the other hand, when driving on a road such as a highway where the possibility of pedestrians being on the roadside is extremely low, if the second illumination pattern of a single bright area is emitted, the illumination area is expanded to reinforce the side areas of the illumination area of ​​the high-beam illumination unit, thereby improving visibility in the distant field of vision. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram showing a state of irradiation of illumination light by the vehicle lighting device according to the embodiment of the present invention.

[0018] Figure 2 It is a structural diagram of a vehicle lighting device according to an embodiment of the present invention.

[0019] Figure 3 It is shown Figure 2A diagram of the illumination area of ​​each lamp in a vehicle lighting device.

[0020] Figure 4 It is shown Figure 2 A diagram of the illumination area of ​​a lamp when a vehicle lighting device is operating in a low beam mode.

[0021] Figure 5 It is shown Figure 2 FIG. 1 is a diagram showing an example of an illumination area of ​​a lamp when a vehicle lighting device is operating in a high-beam mode.

[0022] Figure 6 It is shown Figure 2 FIG. 2 is a diagram showing another example of an illumination area of ​​a lamp when the vehicle lighting device operates in a high-beam mode.

[0023] Figure 7 It is shown Figure 2 A diagram showing an example of an illumination pattern of a variable pattern illumination unit in a vehicle lighting device.

[0024] Figure 8 It is shown Figure 2 FIG. 1 is a diagram showing another example of an illumination pattern of a variable pattern illumination unit in a vehicle lighting device. DETAILED DESCRIPTION

[0025] In the following description, an irradiation area refers to the irradiation area of ​​the light of the lamp, and an irradiation pattern refers to the pattern of bright and dark areas in the irradiation area, the contour shape of the irradiation area, and other irradiation forms.

[0026] Figure 1 Schematic diagram showing the irradiation of the illumination light of the vehicle lighting device 1 according to the embodiment of the present invention. The distribution of the illumination light from the vehicle lighting device 1 is evaluated based on the irradiation pattern formed on the test screen 3, which is a specific virtual vertical plane set in front of the vehicle lighting device 1 installed on the vehicle 2, for example, 25 m in front.

[0027] Figure 2 1 is a diagram showing the structure of a vehicle lighting device 1. Figure 3 1 is a diagram showing the illumination area of ​​each lamp in the vehicle lighting device 1. On the left headlamp unit 4 and the right headlamp unit 5 as lamps, a high beam unit 6, a low beam unit 7, and a projector unit 8 are arranged in order from the inside to the outside in the vehicle width direction of the vehicle 2. In each of the left headlamp unit 4 and the right headlamp unit 5, the high beam unit 6, the low beam unit 7, and the projector unit 8 operate under the control of the lamp control ECU 9.

[0028] The high beam unit 6 includes a light emitting element as a light source, a reflector, a visor defining an irradiation area, and a lens. According to a control signal from the lamp control ECU 9, power is supplied from a power source (not shown) to make the light emitting element emit light. The light from the light emitting element is reflected by the reflector. The reflected light from the reflector is irradiated from the lens to the high beam irradiation area 10 defined by the visor.

[0029] The low beam unit 7 includes a light emitting element as a light source, a reflector, a visor defining an irradiation area, and a lens. According to a control signal from the lamp control ECU 9, power is supplied from a power source (not shown) to make the light emitting element emit light. The light of the light emitting element is reflected by the reflector. The reflected light from the reflector is irradiated from the lens to the low beam irradiation area 11 defined by the visor.

[0030] The projector unit 8 includes a light emitting element as a light source, a spatial light modulator, and a lens. As the spatial light modulator, for example, a device that independently modulates a plurality of reflective elements and reflects light, such as a digital micromirror device (DMD), can be applied. In this case, the projector unit 8 adopts a structure of a digital light processing (DLP: registered trademark) method using a DMD, and can irradiate light from the lens to the front and the surroundings of the vehicle 2 in various specific irradiation patterns.

[0031] The illumination pattern can be in the form of not only various still image patterns but also animated patterns. According to the control signal from the lamp control ECU 9, the driving power is supplied from the power supply not shown in the figure, so that the light emitting element emits light. The light from the light emitting element is spatially modulated by the spatial light modulator driven by the control signal from the lamp control ECU 9, and the light is irradiated from the lens of the projector unit 8 to the front and the surrounding of the vehicle 2 in various specific illumination patterns. That is, the projector unit 8 constitutes a variable pattern illumination unit that can change the form of the illumination pattern.

[0032] refer to Figure 3 , to transfer light from Figure 1 The illumination areas of the high beam unit 6, low beam unit 7 and projector unit 8 when the vehicle lighting device 1 in FIG. 1 illuminates the test screen 3 will be described. Here, the illumination area of ​​the projector unit 8 indicates the illumination area of ​​the projector unit 8 of the right headlamp unit 5.

[0033] The illumination area of ​​the projector unit 8 of the left headlight unit 4 is symmetrical to the illumination area of ​​the projector unit 8 of the right headlight unit 5 with the VV line as the object axis, and is not shown in the figure.

[0034] The structure and function of the projector unit 8 of the left headlight unit 4 are similar to those of the projector unit 8 of the right headlight unit 5. Therefore, hereinafter, regarding the structure and function of the projector unit 8 of the left headlight unit 4, the description of the projector unit 8 of the right headlight unit 5 is cited.

[0035] The low beam irradiation area 11 of the low beam unit 7 has a cutoff line on the opposite lane side extending parallel to the HH line (horizontal line) on the test screen 3, which is further to the right than the VV line (plumb line) in the center of the left-right direction. In addition, there is a cutoff line on the own lane side extending along the HH line at a higher position than the cutoff line on the opposite lane side on the left side. The cutoff line on the opposite lane side and the cutoff line on the own lane side are connected by an oblique cutoff line inclined relative to the HH line. The low beam irradiation area 11 is the lower irradiation area on the lower front side of the vehicle 2.

[0036] The high beam irradiation area 10 of the high beam unit 6 is a rectangle having a long side parallel to the HH line and a short side parallel to the VV line, and occupies a position where the intersection of its diagonal lines is substantially consistent with the intersection of the HH line and the VV line. The high beam irradiation area 10 overlaps with the low beam irradiation area 11 in a partial area below the cutoff line on the opposite lane side and the cutoff line on the own lane side, which are each close to the VV line. The high beam irradiation area 10 is an upper irradiation area that is located above the low beam irradiation area 11 as the lower irradiation area and is located on the center side of the vehicle width direction of the vehicle 2.

[0037] The irradiation area of ​​the projector unit 8 of the right headlamp unit 5, i.e., the right pattern irradiation area 12, changes the contour shape of the area or the form of the irradiation pattern in the area according to the mode switching signal from the lamp control ECU 9, and makes various changes to the irradiation pattern. However, no matter which form is adopted, the right pattern irradiation area 12 is a lateral upper irradiation area that is closer to the outer side of the vehicle width direction of the vehicle 2 than the upper irradiation area (high beam irradiation area 10) and is closer to the upper side than the lower irradiation area (low beam irradiation area 11).

[0038] From the perspective of the capability of the projector unit 8, the right pattern irradiation area 12 can adopt a wider form including an overlapping area 12a that overlaps with the high beam irradiation area 10. When this form is adopted, the right pattern irradiation area 12 is in a transverse trapezoidal shape, the height direction of which is parallel to the HH line and the upper and lower bases are parallel to the VV line. The lower base of the trapezoid that is relatively far from the VV line is longer than the upper base that is relatively close to the VV line. That is, the right pattern irradiation area 12 is in a shape in which the size along the VV line becomes wider toward the outer side in the vehicle width direction of the vehicle 2.

[0039] The lighting control ECU 9 switches the operation mode of the vehicle lighting device 1 based on outputs from a higher-level ECU (not shown), a camera, a light switch, a light switch lever, etc., which are mounted on the vehicle 2. That is, the lighting control ECU 9 supplies control signals to the high-beam unit 6, the low-beam unit 7, and the projector unit 8 to switch the operation mode of each of these units.

[0040] Figure 4 : is a diagram showing the illumination area of ​​the illumination light of the vehicle lighting device 1 when the lighting control ECU9 sets the operation mode to the low beam mode. At night, when the light switch is in the "automatic" position and the light switch lever is in a position other than the low beam, the vehicle lighting device 1 is mostly in the high beam mode. In this state, if the camera detects an oncoming vehicle or a vehicle in front, or a certain number of street lights, the lighting control ECU9 switches the operation mode of the vehicle lighting device 1 to the low beam mode. In the low beam mode, under the control of the lighting control ECU9, the high beam unit 6 is turned off, the low beam unit 7 illuminates the low beam illumination area 11, and the projector unit 8 illuminates the right pattern illumination area 12.

[0041] In the low beam mode, the right pattern irradiation area 12 occupies a wider area of ​​the lateral trapezoidal shape including the overlap area 12a. Figure 7 The first illumination pattern 15 shown alternately repeats bright regions 13 and dark regions 14 to illuminate the patterned illumination light. Figure 7 The first illumination pattern 15 in the image is particularly an oblique rhombus lattice pattern consisting of bright areas 13 of a mesh pattern of oblique rhombus lattices and dark areas 14 surrounded by the bright areas 13 .

[0042] By using the irradiation light of the first irradiation pattern from the projector unit 8 of the right headlight unit 5, the driver can easily recognize the presence of pedestrians on the roadside by utilizing the human visual characteristics. Even in adverse conditions such as nighttime and rainy days, the driver can improve the risk of missing pedestrians.

[0043] Figure 5It is a diagram showing the illumination area of ​​the illumination light of the vehicle lighting device 1 when the lighting control ECU9 sets the operation mode to the high beam mode. At night, when the light switch is in the "automatic" position and the light switch lever is in a position other than the high beam, the vehicle lighting device 1 is mostly in the low beam mode. In this state, when the camera does not detect an oncoming vehicle or a vehicle in front, or a certain number of street lights, the lighting control ECU9 switches the operation mode of the vehicle lighting device 1 to the high beam mode. In detail, the detection by the upper ECU that the vehicle 2 is traveling at a speed of more than 30 km / h, for example, is also regarded as a necessary condition for switching to the high beam mode. In the high beam mode, under the control of the lighting control ECU9, the high beam unit 6 illuminates the high beam illumination area 10, the low beam unit 7 illuminates the low beam illumination area 11, and the projector unit 8 illuminates the right pattern illumination area 12.

[0044] In high beam mode, under the control of the lamp control ECU 9, the form of the illumination pattern of the right side pattern illumination area 12 of the projector unit 8 is changed according to the lighting of the high beam unit 6. That is, the right side pattern illumination area 12 is changed from a form that occupies a wider area of ​​a transverse trapezoidal shape including an overlapping area 12a in low beam mode to a reduced form that does not have an overlapping area 12a and does not overlap with the high beam illumination area 10. The reduction of the right side pattern illumination area 12 is achieved by setting the number of light-emitting elements to be lit in the projector unit 8 to a more limited number than when all are lit, thereby reducing power consumption. In high beam mode, the right side pattern illumination area 12 can also be used. Figure 7 The first illumination pattern shown is a form in which pattern illumination light is emitted from the projector unit 8. When the pattern illumination light is emitted in the first illumination pattern, the driver can easily recognize the presence of a pedestrian on the roadside by utilizing the visual characteristics of a person.

[0045] On the other hand, if the above-mentioned condition of selecting the high beam mode is taken into consideration in the vehicle lighting device 1 under the control of the lamp control ECU 9, there are many cases where the possibility of pedestrians being present on the roadside, such as on a highway, is extremely low. In other aspects of the vehicle lighting device 1, in this case, the side of the high beam illumination area 10 is illuminated with the illumination light from the projector unit 8 for reinforcement. Figure 6 and Figure 8 This situation will be described.

[0046] Figure 6 This is a diagram showing a state where, when the operation mode of the vehicle lighting device 1 is the high-beam mode, the side of the high-beam irradiation area 10 is irradiated with the irradiation light from the projector unit 8 for reinforcement. Figure 6 The right pattern irradiation area 12 of the projector unit 8 in FIG. 1 is a rectangular outline connected in a manner that the area starts at the right end and expands to the right side at the right end of the high beam irradiation area 10. Figure 6 and Figure 8 As shown, the projector unit 8 irradiates the irradiation light in the second irradiation pattern 16 such that the right pattern irradiation area 12 having a rectangular outline is a single bright area. Here, a single bright area refers to not only a clear area with the same illuminance throughout the area, but also includes a case with gradient.

[0047] In addition, the right pattern illumination area 12 can be configured to be able to switch between at least two illumination patterns, namely the first illumination pattern or the second illumination pattern, wherein the first illumination pattern is an alternating and repeated bright area 13 and dark area 14, or can be configured to switch to one of the illumination patterns according to the driving condition of the vehicle 2. The switching at this time can also be performed under the control of the lamp control ECU 9.

[0048] In the vehicle lighting device 1 capable of changing the illumination pattern in the right pattern illumination area 12 as described above, for example, when traveling on a single-lane road, light of a first illumination pattern is irradiated from the projector unit 8. On the other hand, when traveling on a road where pedestrians do not exist, such as a highway, light of a second illumination pattern is irradiated from the projector unit 8. The switching of the illumination pattern is performed under the control of the lamp control ECU 9 to which information related to the current driving condition of the vehicle 2 has been provided, and the information is provided by the upper ECU. When traveling on a single-lane road, the first illumination pattern is applied, and the presence of pedestrians can be easily recognized by the driver by utilizing the visual characteristics of humans. In addition, when traveling on a highway, the second illumination pattern is applied to expand the illumination area to reinforce the side area of ​​the high-beam illumination area 10, thereby being able to improve the visibility of the illumination area to the distant field of vision.

[0049] According to the vehicle lighting device 1 of the present embodiment, the following effects are achieved.

[0050] In the vehicle lighting device 1 of (1), when the operation mode is set to the low beam mode by the lamp control ECU 9, the right pattern irradiation area 12 is irradiated with pattern irradiation light from the DLP (registered trademark) projector unit 8 using DMD in a wide area of ​​a horizontal trapezoidal shape with a first irradiation pattern 15. The first irradiation pattern 15 is an oblique diamond lattice pattern in which bright areas 13 and dark areas 14 are repeated alternately. Thus, the driver can easily recognize the presence of pedestrians on the roadside by utilizing the visual characteristics of the human body. Even under adverse conditions such as night and rainy days, the driver's omission of pedestrians can be improved. On the other hand, when the possibility of pedestrians on the roadside, such as on a highway, is extremely low, under the control of the lamp control ECU 9, the irradiation pattern from the right pattern irradiation area 12 is changed to a second irradiation pattern 16 having a rectangular outline and a single bright area, and the irradiation area is expanded to reinforce the side area of ​​the high beam irradiation area 10. Thus, the visibility of the distant field of vision can be improved.

[0051] In the vehicle lighting device 1 of (2), under the control of the lamp control ECU 9, the irradiation area of ​​the projector unit 8, that is, the right pattern irradiation area 12 is reduced, and does not have an overlapping area 12a with the irradiation area of ​​the high beam unit 6, that is, the high beam irradiation area 10. As a result, the power consumption of the variable pattern irradiation unit is reduced by an amount corresponding to the overlapping area 12a.

[0052] In the vehicle lighting device 1 of (3), when driving on a single-lane road, by irradiating the light of the first irradiation pattern 15 that alternately repeats the bright area 13 and the dark area 14 from the projector unit 8, the driver can easily recognize the presence of pedestrians by utilizing the human visual characteristics. On the other hand, when driving on a road such as a highway where the possibility of pedestrians on the roadside is extremely low, if the light of the second irradiation pattern 16 of a single bright area is irradiated, the irradiation area is expanded to reinforce the side area of ​​the high-beam irradiation area 10, thereby improving the visibility of the distant field of view. That is, under the control of the lamp control ECU 9, the first irradiation pattern 15 and the second irradiation pattern 16 are switched according to the driving condition of the vehicle, thereby preventing the driver from missing pedestrians and improving the visibility of the distant field of view.

[0053] The above is an explanation of the embodiment of the present invention, but the present invention is not limited thereto. The detailed configuration may be appropriately changed within the scope of the main purpose of the present invention. In the above embodiment, a configuration is adopted in which the first illumination pattern 15 and the second illumination pattern 16 are switched according to the driving condition of the vehicle under the control of the lamp control ECU 9. Alternatively, for example, the operation of the projector unit 8 may be managed by a higher-level ECU that always monitors the driving condition of the vehicle, and the first illumination pattern 15 and the second illumination pattern 16 may be switched.

[0054] Reference numerals

[0055] 1Vehicle lighting device

[0056] 2 Vehicles

[0057] 3 Test Screen

[0058] 4 Left side headlamp unit

[0059] 5Right headlamp unit

[0060] 6 high beam units

[0061] 7 low beam units

[0062] 8Projector unit (variable pattern irradiation unit)

[0063] 9 Lighting control ECU

[0064] 10 High beam illumination area (upper illumination area)

[0065] 11 Low beam illumination area (lower illumination area)

[0066] 12Right pattern irradiation area (upper side irradiation area)

[0067] 12a Overlapping area

[0068] 13 Bright Area

[0069] 14 Dark Area

[0070] 15 First irradiation pattern

[0071] 16 Second irradiation pattern

Claims

1. A vehicle lighting device, comprising: The low beam illumination part illuminates the lower illumination area on the lower side in front of the vehicle; a high beam irradiation portion for illuminating an upper irradiation area which is located above the lower irradiation area and on the center side in the vehicle width direction; and The variable pattern irradiation unit illuminates the upper lateral irradiation area in a form capable of changing the irradiation pattern. The upper lateral irradiation area is a lateral area located further outward in the vehicle width direction than the upper irradiation area and further up than the lower irradiation area.

2. The vehicle lighting device according to claim 1, wherein: The variable pattern illumination unit changes the form of the illumination pattern according to whether the high beam illumination unit is lit.

3. The vehicle lighting device according to claim 1 or 2, wherein: The variable pattern illumination unit can switch between at least two illumination patterns, namely a first illumination pattern and a second illumination pattern, and switch to any one of the illumination patterns according to the driving conditions of the vehicle. The first illumination pattern is an alternating pattern of bright and dark areas, and the second illumination pattern is a single bright area.

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