1. Field of the Invention
The present invention relates to a vehicular lighting unit for enhancing an accuracy of when a driver of another vehicle and a pedestrian looking a vehicle perceive the vehicle, and a vehicle of which a perceived accuracy is enhanced.
2. Description of the Related Art
Generally in a traffic environment where a large variety of vehicles run, a larger vehicle is apt to be firstly found by a driver of another vehicle and a pedestrian. In addition, a smaller vehicle such as a two-wheeled vehicle is seen as farther than a larger vehicle such as a truck, and a speed of the former is also felt slower.
For example, in a case that a two-wheeled vehicle and a truck of which distances from own vehicle are same are nearing from an opposite lane during waiting for a right turn at an intersection, a driver is apt to firstly find the truck. Even if a two-wheeled vehicle is perceived to be farther, and the vehicle and a truck run at a same speed, the vehicle results in being perceived to be slower.
In order to solve such the problem is conventionally disclosed a technology of attaching a lighting for enhancing a perceived accuracy at a front side and rear side of a two-wheeled vehicle (see Japanese Patent Laid-Open Publication No. 2003-300488).
In addition, in order to make a driver and a pedestrian recognize an existence of a four-wheeled vehicle during daytime is disclosed a technology of arranging a daytime-run light at lower portion of a headlight, and lighting the light during daytime (see Japanese Patent Laid-Open Publication No. 2004-51080).
However, although attaching vehicle supplementary lights to respective proper positions of a two-wheeled vehicle and a four-wheeled vehicle contributes to enhancing a perceived accuracy of a distance and a speed for each vehicle, a problem cannot be solved that the distance and the speed are differently perceived between different kinds of vehicles. In addition, the technology disclosed in the Japanese Patent Laid-Open Publication No. 2004-51080 cannot grasp a change of a plane size when recognized by eye, and an accuracy in perceiving a speed is not enhanced, because daytime-run lights are arranged in a row at lower portion of a headlight.
Consequently, there is a need for enhancing a perceived accuracy of a vehicle.
In order to solve the problem, the present invention provides a vehicular lighting unit arranged at a front side not to be in a row and comprising at least not less than three supplementary lights having an equivalent color and brightness.
In accordance with such the vehicular lighting unit, because supplementary lights having an equivalent color and brightness are plurally arranged, changing a vertical position and a horizontal position, and thereby the plurality of the supplementary lights are grasped as a combination and like a plane, a perceived accuracy of the vehicle is enhanced.
It is preferable that these supplementary lights are arranged at equivalent positions for any one of a two-wheeled vehicle, a four-wheeled passenger vehicle, and a large size vehicle.
Thus supplementary lights are arranged at equivalent positions even if vehicle kinds are different, and thereby the vehicle can be perceived with an equivalent distance and speed regardless of the vehicle size.
Then in the lighting unit each of the supplementary lights arranged outside is preferably in a range of 460 to 1715 mm in a vertical direction. In addition, at least three brightnesses out of the supplementary lights are preferably in a range of ±40% from an average of the brightnesses. Moreover, in the supplementary lights each one arranged outside is preferably in a range of 240 to 840 mm in a horizontal direction.
A plurality of supplementary lights are arranged in such the ranges, and thereby become easier to be recognized as a combination. In addition, if in such the ranges, supplementary lights can be arranged at proper positions in various vehicle kinds.
In addition, it is preferable that the supplementary lights are symmetrically arranged, specifically, from center of left and right of the vehicle. Thus the vehicle position can be accurately perceived.
In addition, the present invention provides a vehicle where a vehicular lighting unit thus described is attached and thereby a perceived accuracy of the vehicle is enhanced.
Here will be described a first embodiment of the present invention in detail, referring to drawings as needed.
As shown in
Making a description more in detail, the supplementary lights 11R and 11L are respectively horizontally arranged side by side at positions near ground G, for example, at a position of 300 mm from the ground G, and are fixed to a bumper B1. In addition, the supplementary lights 11R and 11L are arranged, making the center of the left/right of the vehicle V1 to be the border, and arranged at a width of 420 mm in an outside distance of each of the supplementary lights 11R and 11L.
The supplementary lights 12R and 12L are horizontally arranged side by side in a left/right (horizontal) direction at positions higher than those of the supplementary lights 11R and 11L. For example, the supplementary lights 12R and 12L are arranged so that their upper end positions respectively become 460 mm from lower end positions of the supplementary lights 11R and 11L. In addition, the supplementary lights 12R and 12L are symmetrically arranged, making the center of the left/right of the vehicle V1 to be the border, and arranged at a width of 660 mm in an outside distance of each of the supplementary lights 12R and 12L.
As the four supplementary lights 11R, 11L, 12R, and 12L are used such ones that are a same color and brightness and recognized from a human by eye.
Here, if a same color is in a range of not being felt oddly, compared to a basic lighting color, it is not specifically limited; however, in a case that a viewing angle for an observed lighting is ≦4°, a color is preferable of which a chromaticity from a chromaticity point of a basic lighting color (F1) is within a definite range in the CIE (Commission Internationale de l'Eclairage) 1976 UCS (Uniform-Chromaticity-Scale) chromaticity diagram (XYZ color system) (defined in JIS (Japanese Industrial Standard) Z 8729). For example, in a case that the chromaticity point of the lighting color (F1) is F1(u1′, v1′), and that of a lighting color (F2) compared is F2(u2′, v2′), a chromaticity difference ΔE between the chromaticity point F1 and the chromaticity point F2 are expressed in the following equation (1):
ΔE=√{square root over (((u1′-u2′)2+(v1′-v2′))}2) Eq. (1)
For example, it is preferable to make a color, of which the chromaticity difference ΔE expressed in the equation (1) is ≦0.10, to be a same color.
Showing a chromaticity diagram for reference,
In addition, a same brightness means a brightness of a range of ±40% from an average of that of each supplementary light. Mentioning the example of the embodiment, it is meant that the four supplementary lights 11R, 11L, 12R, and 12L are respectively in a range of ±40% from an average of their brightnesses.
An arranged position of each of the supplementary lights 11R, 11L, 12R, and 12L is preferably provided, as shown in
In addition, the supplementary lights 12R, 12L are preferably arranged in a range of ≦1985 mm in height from the ground G.
Thus each of the supplementary lights 11R, 11L, 12R, and 12L is arranged, and thereby they are grouped and perceived as one combination. Therefore, if the supplementary lights 11R, 11L, 12R, and 12L move similarly, a driver of another vehicle and a pedestrian perceive a position (distance) and speed of the vehicle V1, making lights emitted from the grouped supplementary lights 11R, 11L, 12R, and 12L to be a clue.
Although a size of each supplementary light 11R, 11L, 12R, and 12L can be configured, for example, as shown in
Assuming that a vehicle running on an opposite lane is running at a speed of 60 km/h, it is preferable that a supplementary light has at least a size of 30 mm in longitudinal and 1200 mm in traversal, and a brightness of ≧137 cd/m2 and such a sort not obstructing a traffic (for example, ≦300 cd/m2 according to a Japanese regulation).
Each supplementary light 11R, 11L, 12R, and 12L comprises at least one illuminant. The illuminant is, for example, an LED (Light Emitting Diode), an electric bulb, a discharge tube, and an EL (Electroluminescence).
Such the vehicular lighting unit 10 can be applied not only to a four-wheeled passenger vehicle but also to other vehicle kinds.
As shown in
As shown in
In addition, although not shown, it is also possible to provide the supplementary lights 11R, 11L so as to be housed in the front fork 21 or to attach them to an undercowl.
As shown in
In addition, in a case of attaching the vehicular lighting unit 10 to a large size vehicle, because the vehicle has a comparatively large and flat front side, it is preferable as shown in
Thus arranging each supplementary light 11R, 11L, 12R, and 12L in the range shown in
In such the vehicular lighting unit 10 and a vehicle attached with the unit 10, a vehicle position is grasped by the unit 10 regardless of a vehicle body size; the unit 10 and the vehicle are perceived as a similar position and speed by a driver of another vehicle and a pedestrian regardless of its vehicle kind. Therefore, even in a traffic environment where various vehicle kinds are mixed, a position and speed of each vehicle with the vehicular lighting unit 10 are correctly perceived, and thereby a smooth vehicle traffic can be realized.
The present invention is not limited to the embodiment, and it goes without saying that the embodiment can be appropriately changed and performed.
For example, a number of supplementary lights may not be four, and may be three or not less than five. Also in this case it is preferable that each supplementary light is symmetrically arranged, making center of left/right of a vehicle to be a border.
In addition, if although it is preferable that each supplementary light has an equivalent color and brightness, not less than three supplementary lights have the equivalent color and brightness, it is acceptable that a color of some supplementary light is slightly different or a brightness thereof is low.
Next will be described examples of the present invention.
A first example is an example of experimenting respective relationships of supplementary lights.
Using a distance d between the subject vehicle 35 and the oncoming vehicle 36 and speed v of the latter of this time, and calculating d/v, a time is obtained from the timing, when the brake pedal was stepped on, to that when the vehicles 35 and 36 pass by. The time is called a critical time gap. Generally, in a traffic environment, because perceiving a two-wheeled vehicle farther and slower causes an erroneous action of a driver, it is assumed in the example that the larger the critical time gap is, the higher a perceived accuracy is evaluated.
In the example, under each condition shown in
Firstly will be described examples 1-1 and 1-2.
The examples 1-1 and 1-2 were experimented by real vehicles, changing a distance between the upper supplementary lights 12R, 12L and the lower supplementary lights 11R, 11L. In the experiments critical time gaps were measured and averaged for five subjects.
As the result, as shown in
Next will be described examples 2-1 and 2-2.
The examples 2-1 and 2-2 were experimented by simulator, changing a distance between the left/right supplementary lights 12L, 11L and 12R, 11R. In the experiments critical time gaps were measured and averaged for four subjects.
As the result, as shown in
Meanwhile, as a conventional example compared to the examples 2-1 and 2-2, although there exists a comparison example 2 of
In addition, a difference between the critical time gap values of the examples 1-1 and 1-2 and those of the examples 2-1 and 2-2 is that between a real vehicle and a simulator. Because it is confirmed that there occurs a difference of about one second, it can be said that a substantially same effect is recognized in the examples 1-1 and 1-2 and the examples 2-1 and 2-2.
Next will be described examples 3-1, 3-2, and 3.3.
The examples 3-1, 3-2, and 3.3 were experimented by simulator, changing a distance between left supplementary lights and right supplementary lights. As the result, as shown in
Next will be described a second example of comparing an effect between a two-wheeled vehicle (scooter) and a four-wheeled passenger vehicle.
In the second example the vehicular lighting units of the present invention are respectively attached to the two-wheeled vehicle and the four-wheeled passenger vehicle, and the critical time gaps thereof were measured.
Each vehicular lighting unit was arranged, as shown in
An experimental method was performed by real vehicle.
As the result, as shown in
On the other hand, in a case of there existing supplementary lights, the critical time gaps of both of the two-wheeled vehicle and the four-wheeled passenger vehicle were 6.0 seconds and same. In other words, it can be said that both of the two-wheeled vehicle and the four-wheeled passenger vehicle were perceived as a same distance and speed.
Accordingly, it is confirmed that the present invention not only enhances the perceived accuracy of a distance and a speed but also has an effect of perceiving the distance and the speed as same even between different vehicle kinds.
A third example compares an effect between cases of numbers of supplementary lights, two and four.
With respect to a two-wheeled vehicle (scooter) were measured the critical time gaps in a case that two supplementary lights 12, 11 were arranged up/down as shown in
As the result, as shown in
Thus by arranging four supplementary lights not in a row but like a plane seen from front, it is confirmed that the perceived accuracy is more enhanced than a case of only two supplementary lights being arranged like a conventional technology.
Number | Date | Country | Kind |
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2005-277193 | Sep 2005 | JP | national |