JP2008204727A - Vehicle headlamp device - Google Patents

Abstract

An object of the present invention is to improve visibility in consideration of characteristics of human eyes.
When ambient illuminance is low, blue light has better visibility from the viewpoint of visibility characteristics, and therefore light containing a large amount of blue component light is emitted from a headlamp at night. At this time, if there is little red component light, visibility such as color and shape deteriorates, so the central region of the irradiation area irradiated from the headlamp and projected onto the road surface is more red component light than other areas. From an inclined surface that is inclined upward by a predetermined angle (for example, 10 °, 15 °, etc.) with respect to a horizontal plane passing through the headlamp, and including the headlamp. The upper upper region is irradiated with light so that the irradiation amount of the red component light is larger than the other regions.
[Selection] Figure 2

Description

  The present invention relates to a vehicle headlamp device, and more particularly, to a headlamp device that emits light to improve visibility in front of the vehicle.

  Generally, a headlight is provided in a vehicle, and forward visibility is ensured by irradiating light from the headlight to the front of the vehicle. Furthermore, the visibility from other vehicles etc. is ensured by irradiating light ahead of a vehicle from a headlamp.

Further, in the technique described in Patent Document 1, it is proposed that the lighting color is switched to yellow or white according to the external environment to improve driver visibility and visibility in other vehicles. Specifically, in the technique described in Patent Document 1, when the lamp is on, the retroreflectance is read, and the amount of light that decreases when the lamp color is yellow is corrected. When the retroreflectance is a predetermined value or more, When the light color is yellow, the retroreflectance is less than the specified value and the fog switch is on or the wiper wiping speed is high, the light color is yellow, the fog switch is off and the wiper wiping speed is low, Because the road surface reflectance is low, the light color is white.
JP-A-7-144777

  However, the technique described in Patent Document 1 has room for improvement in consideration of changes in the characteristics of the human eye depending on the surrounding environment such as brightness.

  The present invention has been made in view of the above facts, and an object thereof is to improve visibility in consideration of the characteristics of the human eye.

  In order to achieve the above object, the invention according to claim 1 includes a larger amount of blue component light than red component light, and a predetermined region in the irradiation region has a larger amount of red component light irradiation than other regions. As described above, an irradiating means for irradiating light in front of the vehicle is provided.

  According to the first aspect of the present invention, the irradiating means irradiates the front of the vehicle with light containing more blue component light than red component light. As a result, in the human visual sensitivity characteristic, blue is higher in sensitivity than red in a dark place, and thus visibility can be ensured when the headlamp device is turned on in a dark surrounding environment.

  However, colors and shapes are recognized by the cones of photoreceptor cells, but the cones are more sensitive to red component light. Therefore, the irradiating means irradiates light so that a predetermined area in the irradiation area has a larger amount of red component light than other areas, thereby improving the color and shape recognizability in the predetermined area. And the visibility can be improved in consideration of the characteristics of the human eye.

  For example, since a traffic sign or the like exists in an upper area that is inclined upward by a predetermined angle with respect to a horizontal plane passing through the irradiation means and is above the inclined surface including the irradiation means, the predetermined area is defined in claim 2. As in the present invention, the predetermined region is inclined upward by a predetermined angle with respect to the horizontal plane passing through the irradiating means, and an upper area above the inclined surface including the irradiating means is applied, and the predetermined area has a red component more than other areas. By irradiating light so that the amount of light irradiation increases, the color and shape of traffic signs and the like can be improved, and the visibility of traffic signs and the like is improved.

  In addition, since the cone of photoreceptor cells has the highest sensitivity of the visual center, the predetermined region is applied with the central region of the irradiation region projected on the road surface as in the invention described in claim 3, By irradiating the predetermined area with light so that the irradiation amount of the red component light is larger than that of the other areas, it is possible to improve road surface signs and front recognition.

  The invention according to claim 4 changes the color of the light of the headlamp that irradiates light ahead of the vehicle, and irradiates the vehicle front with light that contains more blue component light than red component light, And a control unit that controls the changing unit so that a predetermined region in the irradiation region has a larger amount of red component light irradiation than other regions.

  According to the fourth aspect of the present invention, the changing means changes the color of light emitted from the headlamp to the front of the vehicle. The headlamp uses LEDs of a plurality of colors (for example, three primary colors of red, blue, and green) as a light source, and the changing means changes the number of light emission or current value of the LEDs of each color, thereby changing the headlight. The color of the light emitted from the lamp to the front of the vehicle can be changed. Or in the headlamp which applied the discharge lamp or the halogen lamp as a light source, you may make it change the color of the light irradiated to the vehicle front by using the filter etc. which can change a color.

  In the control means, the changing means is controlled so as to irradiate the front of the vehicle with light containing more blue component light than red component light. By controlling the control means in this way, the human visual sensitivity characteristic is higher in blue than in red in a dark place.Therefore, when the headlamp is turned on when the surrounding environment is dark, Sex can be secured.

  However, colors and shapes are recognized by the cones of photoreceptor cells, but the cones are more sensitive to red component light. Therefore, the control means controls the changing means so that the predetermined area in the irradiation area has a larger amount of red component light irradiation than the other areas, thereby improving the color and shape recognizability in the predetermined area. And the visibility can be improved in consideration of the characteristics of the human eye.

  For example, since there is a traffic sign or the like in the upper region above the inclined surface including the headlamp, which is inclined upward by a predetermined angle with respect to the horizontal plane passing through the headlamp, the control means is provided in claim 5. As in the described invention, the upper region above the inclined surface including the headlamp is inclined at a predetermined angle with respect to the horizontal plane passing through the headlamp, and the irradiation amount of the red component light is higher than other regions. By controlling the changing means so as to increase, the recognizability of the color and shape of traffic signs and the like can be improved, and the visibility of traffic signs and the like is enhanced.

  In addition, since the cone of photoreceptor cells has the highest sensitivity of the visual center, the control means, as in the invention according to claim 6, is such that the central area of the irradiation area projected on the road surface is red than the other areas. By controlling the changing means so that the irradiation amount of the component light is increased, it is possible to improve the road surface marking and the front recognizability.

  According to the seventh aspect of the present invention, the change means for changing the light color of the headlamp that irradiates light ahead of the vehicle, the illuminance detection means for detecting the illuminance around the vehicle, and the detection result of the illuminance detection means The change means is controlled so that the blue component light is larger than the red component light in the case of the predetermined low illuminance state, and the blue color is obtained in the case where the detection result of the illuminance detection means is a predetermined high illuminance state. Control means for controlling the changing means so that the red component light is larger than the component light, and the control means controls the changing means so that the blue component light is larger than the red component light. In this case, the changing means is further controlled so that a predetermined area in the irradiation range of the headlamp has a larger amount of red component light than that of the other areas.

  According to the seventh aspect of the present invention, the changing means changes the color of light emitted from the headlamp to the front of the vehicle. The headlamp uses LEDs of a plurality of colors (for example, three primary colors of red, blue, and green) as a light source, and the changing means changes the number of light emission or current value of the LEDs of each color, thereby changing the headlight. The color of the light emitted from the lamp to the front of the vehicle can be changed. Or in the headlamp which applied the discharge lamp or the halogen lamp as a light source, you may make it change the color of the light irradiated to the vehicle front by using the filter etc. which can change a color.

  By the way, the human visual sensitivity characteristic has a characteristic that blue is higher in sensitivity than red in a dark place and red is higher in sensitivity than blue in a bright place. Therefore, the illuminance detection means detects the vehicle illuminance, and the control means changes the blue component light more than the red component light when the detection result of the illuminance detection means is a predetermined low illuminance state. And the changing means is controlled so that the red component light is larger than the blue component light when the detection result of the illuminance detecting means is a predetermined high illuminance state. As a result, even if the brightness of the surrounding environment changes, the front of the vehicle is illuminated with light having a color that is highly visible to humans, so visibility from other vehicles and the like can be improved. Moreover, the visibility of the light irradiation object by a headlamp can also be improved.

  However, as described above, colors, shapes, and the like are recognized by cones of photoreceptor cells, but the cones are more sensitive to red component light. Therefore, when the control means controls the changing means so that the blue component light is larger than the red component light, the predetermined area in the irradiation range of the headlamp is irradiated with the red component light more than the other areas. By further controlling the changing means so as to increase, the color and shape recognizability in a predetermined area can be improved, and the visibility can be improved in consideration of the characteristics of human eyes.

  As described above, according to the present invention, the blue component light is included more than the red component light, and the predetermined region in the irradiation region is disposed in front of the vehicle so that the irradiation amount of the red component light is larger than the other regions. By irradiating light, there is an effect that visibility can be improved in consideration of characteristics of human eyes.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. In the present embodiment, the “red component light” is light having a long wavelength with a wavelength of about 530 nm as a boundary, particularly 530-600 nm, where the visibility of the cones of the photoreceptor cells is high, and the “blue component light” is about the wavelength. The description will be made on the assumption that 450-530 nm is a short wavelength light with a boundary of 530 nm, and particularly the visibility of the rod of the photoreceptor cell is high.

[First Embodiment]
FIG. 1 is a diagram showing a schematic vehicle mounting position of the headlamp apparatus according to the first embodiment of the present invention.

  As shown in FIG. 1, the headlamp device according to the first embodiment of the present invention includes a headlamp 10 that is provided in the vicinity of the front end of the vehicle and that irradiates light in front of the vehicle.

  As shown in FIG. 2, the headlamp 10 irradiates light ahead of the vehicle and has a predetermined light distribution characteristic, and light is emitted farther on the passenger side than on the driver side. It is supposed to be light distribution. FIG. 2 shows an example of a right-hand drive vehicle.

  By the way, the visibility characteristic with respect to the human color changes depending on the ambient illuminance, and as shown in FIG. 3, when the periphery is dark (dark adaptation region), the visibility of blue is higher than that of red, and the periphery is bright. In the case (light adaptation region), the sensitivity of red is higher than that of blue. That is, blue light is easier to see at night, and red light is easier to see at daytime. And since the headlamp 10 is generally used at night, in this embodiment, the headlamp 10 irradiates light with the irradiation amount of blue component light larger than red component light.

  However, although the visibility at night can be improved by increasing the amount of irradiation of blue component light, if the amount of red component light is small due to the characteristics of human photoreceptor cells, the color and shape recognizability deteriorates.

  Therefore, as shown in FIG. 2, the headlamp device according to the present embodiment has an area near the center of the irradiation area irradiated from the headlamp 10 and projected onto the road surface (hereinafter referred to as the center area 12). The light is emitted so that the amount of the red component light is larger than that of the other regions, and as shown in FIG. 4, a region above a predetermined angle (for example, 10 °, 15 °, etc.) above the horizontal plane ( Hereinafter, the upper region 14) is irradiated with light so that the irradiation amount of the red component light is larger than that of the other regions. In FIG. 4, the upper region 14 is shown as a region above a predetermined angle with respect to a horizontal plane including the horizon and the occupant's eye point. However, the eye point changes depending on the occupant. It is preferable to apply a region that is inclined upward by a predetermined angle with respect to a horizontal plane passing through the headlamp 10 and that is above the inclined surface including the headlamp 10.

  FIGS. 5A and 5B are views showing an example of a headlamp applicable to the vehicular illumination apparatus according to the embodiment of the present invention.

  For example, as shown in FIG. 5A, the headlamp 10 can be provided with a plurality of color LED light sources 16, and the headlamp driver 18 turns on and off the plurality of color LED light sources 16. By controlling, it is possible to irradiate light so as to have the light distribution characteristics shown in FIGS. 2 and 4, and the light emitted from the LED light source 16 corresponding to the above-described central region 12 and upper region 14 is different. By irradiating light having a red component more than light emitted from the LED light source 16, the amount of red component light irradiated in the central region 12 and the upper region 14 can be increased. 5A shows an example of a headlamp having two LED lamps 17 each having a plurality of LED light sources 16. For example, one LED lamp 17 is used for a low beam and the other LED lamp 17 is used. You may make it use properly for high beams.

  Further, as shown in FIG. 5B, the headlamp 10 can be applied with a light source 20 such as a halogen lamp or a discharge lamp lamp. In this case, the headlamp 10 corresponds to the central region 12 described above. A central region light source 22 that irradiates light to the region, and an upper region light source 24 that irradiates light to a region corresponding to the upper region 14, and is irradiated from the central region light source 22 and the upper region light source 24. The headlamp lighting circuit 26 controls each light source as a light source that emits light having more red component light than the light emitted from the light source 20, so that the red component in the central region 12 and the upper region 14 is controlled. The amount of light irradiation can be increased.

  In addition to the above, various light sources and filters can be applied. For example, light from the light source is irradiated forward through the filter, and the central region 12 and the upper region 14 are irradiated by the filter. It is possible to increase the amount of red component light.

  Then, the effect | action of the headlamp apparatus concerning 1st Embodiment of this invention comprised as mentioned above is demonstrated.

  First, when lighting of the headlamp 10 is instructed by a switch (not shown) that instructs lighting of the headlamp, the headlamp 10 is turned on.

  The light emitted from the headlamp 10 is emitted in a predetermined light distribution in front of the vehicle. At this time, in the present embodiment, the headlamp 10 is irradiated with light containing a large amount of blue component light, thereby improving nighttime visibility.

  In the present embodiment, the central region 12 shown in FIG. 2 and the upper region 14 shown in FIG. 4 are irradiated with a larger amount of red component light than the other regions.

  Here, the characteristics of the human eye will be described in order to explain the effect of irradiating the central region 12 and the upper region 14 with a large amount of red component light.

  Human visual cells have two types of cells (rods and cones) that are necessary to feel color. A rod is a cell that feels the brightness of light, and a cone is a cell that feels color and shape.

  As shown in FIG. 6A, the rods and cones are distributed on the retina with the retinal center at 0 °, and the distribution is as shown in FIG. 6B. In FIG. 6, the horizontal axis indicates the position on the retina, and the vertical axis indicates the number of receptors per square millimeter.

  The cones are concentrated in the central part of the retina, and there are few in the peripheral part. Conversely, there are many rods in the peripheral part. In addition, there is no tourist cell at the place where the axon of the ganglion cell becomes the optic nerve and goes out of the eyeball, and a blind spot is formed.

  And the rod works in the dark and the cone works in the bright. In addition, as shown in FIG. 6C, the relationship between the sensitivity and wavelength of the rod and cone is high in sensitivity of long wavelength component light (about 550 nm), and the rod is short wavelength component light (about approx. The sensitivity of 510 nm) is high.

  That is, according to the human visual sensitivity characteristic shown in FIG. 6, the visibility can be improved by irradiating the headlamp 10 with light containing a large amount of blue component light at night, but if the red component light is small Since the sensitivity of the cone is lowered, the visibility such as color and shape is deteriorated.

  Therefore, in the present embodiment, by increasing the irradiation amount of the red component light in the predetermined region (the central region 12 and the upper region 14) (for example, increasing the wavelength near 550 nm where the sensitivity of the cone is high), And shape recognition can be improved.

  That is, since the cone of photoreceptor cells has the highest visual center sensitivity, it is possible to improve road surface marking and front recognition by increasing the amount of red component light irradiation in the central region. Moreover, since traffic signs etc. exist in the upper area | region 14, the recognition property of a traffic sign etc. can be improved by increasing the irradiation amount of the red component light of the upper area | region 14. FIG.

  Therefore, the visibility can be improved in consideration of the characteristics of the human eye by increasing the irradiation amount of the red component light in the central region 12 as compared with other regions as in the present embodiment.

[Second Embodiment]
Then, the headlamp apparatus concerning 2nd Embodiment of this invention is demonstrated.

  In the first embodiment, assuming that the headlamp 10 is lit at night, light including blue component light is emitted from the headlamp 10 so that the central region 12 and the upper region 14 are more than the other regions. In the second embodiment, the light emitted from the headlamp 10 according to the ambient illuminance is not limited to the lighting of the headlamp 10 at night. A case will be described in which the central region 12 and the upper region 14 are made to have a larger amount of red component light irradiation than the other regions while controlling the color of the light.

  In addition, the headlamp of this embodiment demonstrates what applied the LED headlamp which used LED as the light source.

  Similar to the headlamp of the first embodiment, the LED headlamp of the headlamp apparatus according to the second embodiment is provided near the front end of the vehicle and irradiates light in front of the vehicle. The LED headlamp irradiates light ahead of the vehicle, has a predetermined light distribution characteristic, and has a light distribution in which light is irradiated farther on the passenger seat side than on the driver seat side.

  In addition, as shown in FIG. 7A, the LED headlamp of the present embodiment includes one LED that emits R (red) color light, two LEDs that emit G (green) color light, and B (blue). The LED light source 30 includes a plurality of LED groups 28 each having one LED that emits colored light. As shown in FIG. 7B, the LED group 28 may include a plurality of RGB colors (R × 9, G × 18, B × 9 in FIG. 7B). Alternatively, the state shown in FIG. 7B may be configured as one LED light source 30 instead of the LED group 28.

  FIG. 8 is a block diagram showing a configuration of a headlamp apparatus according to the second embodiment of the present invention.

  The LED headlamp 11 of the present embodiment is controlled to be turned on by the control device 32, and the control device 32 has a CPU 32A, a RAM 32B, a ROM 32C, and an I / O interface (I / O) 32D connected to the bus 32E. It consists of a microcomputer. Further, a predetermined map 34 for changing the color of light emitted from the LED headlamp 11 is provided in the control device 32, and is connected to the I / O 32D.

  An LED driver 36 to which the LED headlamp 11 is connected, an ignition switch 38, a light control switch 40, and an illuminance sensor 42 are connected to the I / O 32D.

  The LED driver 36 controls driving of each color LED of the LED headlamp 11. The LED driver 36 changes the color of the light emitted from the LED headlamp 11 by selectively driving the LED in accordance with an instruction from the control device 32 or controlling the current value applied to the LED. It is possible.

  The ignition switch 38 issues a power supply instruction to the control device 32, and power is supplied to the control device 32 when the ignition switch 38 is operated. Note that the ignition switch 38 may not be connected to the control device 32 but may be constantly supplied with power.

  The light control switch 40 is provided in the vicinity of a steering handle for steering the vehicle and the control device 32 gives an instruction to turn on / off the LED headlamp 11 or switch the irradiation range (switch between high and low) as an operation result of the occupant. Output to.

  The illuminance sensor 42 is provided, for example, near the defroster of the instrument panel, detects the illuminance around the vehicle, and outputs the detection result to the control device 32.

  By the way, as described in the first embodiment, the visibility characteristics with respect to human colors change depending on the ambient illuminance. As shown in FIG. 9A, when the periphery is dark, blue is more visible than red. When the sensitivity is high and the surroundings are bright, red has a characteristic that sensitivity is higher than blue. That is, blue light is easier to see at night, and red light is easier to see at daytime.

  Therefore, in the present embodiment, as shown in FIG. 9A, the visibility characteristics for human colors are as follows: a darker area than the threshold value LL is a dark-adapted area, a brighter area than the threshold LH is a bright-adapted area, and a threshold value LL to a threshold value. The LH region is divided into three regions, which are intermediate regions, and the color of the light emitted from the LED headlamp 11 is controlled according to the ambient illuminance so that each region has a color with high human visibility.

  Specifically, based on the detection result of the illuminance sensor 42, the control device 32 uses the dotted line in FIG. 9B when the ambient illuminance such as nighttime is dark (in the dark adaptation state corresponding to the dark adaptation area). When the light intensity of each LED of the LED headlamp 11 is controlled so that the blue component light of the light emitted from the LED headlamp 11 increases as in the case of the spectral intensity shown, the ambient illuminance such as daytime is bright (bright LED headlamps so that the red component of the light emitted from the LED headlamps 11 increases as in the spectral intensity indicated by the solid line in FIG. 9B in the bright adaptation state corresponding to the adaptation region). When the light emission of each LED 11 is controlled and the illuminance is intermediate between night and daytime such as dusk (in the intermediate state corresponding to the intermediate region between the dark adaptation region and the light adaptation region), one point in FIG. Like the spectral intensity indicated by the chain line, the red and blue components are almost equivalent. And controls the light emission of each LED in the LED headlamp 11 so. For example, in the intermediate state, the light emission of each color LED is controlled so that the ratio of the color of light emitted from the LED headlamp 11 is R: G: B = 1: 2: 1. The LED emission of each color is offset to the reference so that R: G: B = 2: 1: 1 in the light adaptation state and R: G: B = 1: 1: 2 in the dark adaptation state. To control. The light emission of each LED may be controlled by controlling the number of light emitting LEDs of each color, or the amount of light emission is controlled by controlling the current value applied to each color LED (for example, controlling the duty ratio). You may do it. The spectral intensity in FIG. 9B shows a relative value, and may be controlled so that the total illuminance emitted from each LED headlamp 11 does not change or may be controlled differently.

  That is, in the present embodiment, the map 20 stores a lookup table or the like in which the number or current value of each LED to emit light corresponding to the detected illuminance is stored, so that light is emitted according to the detection result of the illuminance sensor 42. The number or current value of each color LED is read from the map 20 and driven. Specifically, when the detection result of the illuminance sensor 42 corresponds to the light adaptation region, the control device 32 reads the light emission number or current value of each color LED corresponding to the light adaptation state from the map 20 as the light adaptation state. In the case of corresponding to the dark adaptation region, the dark adaptation state is set as the dark adaptation state, and the light emission number or the current value of each color LED corresponding to the dark adaptation state is read from the map 20. The light emission number or current value of the corresponding LED of each color is read from the map 20, and the light emission of each LED of the LED headlamp 11 is controlled.

  In addition, as described in the first embodiment, when the red component light is small, the recognizability of the color and the shape is degraded. Therefore, in the headlamp device according to the present embodiment, when the ambient illuminance is decreased, as described above. The LED headlamp 11 is controlled so that the amount of blue component light is increased at the same time. However, in the central region 12 and the upper region 14 described in the first embodiment, the amount of red component light is larger than the other regions. To control. That is, in this embodiment, the LED light source or LED light source group 28 corresponding to the central region 12 and the upper region 14 is determined in advance, and when the control is performed so that the blue component light increases, The LED light source or LED light source group 28 corresponding to the region 14 is controlled so that the amount of red component light is larger than that of the other regions.

  Then, an example of the process performed by the control apparatus 32 of the headlamp apparatus concerning the 2nd Embodiment of this invention comprised as mentioned above is demonstrated. FIG. 10 is a flowchart showing an example of the flow of processing performed by the control device 32 of the headlamp apparatus according to the second embodiment of the present invention.

  When the light control switch 40 is operated by the occupant and the LED headlamp 11 is turned on, in step 100, the LED headlamp 11 is turned on in a standard state. That is, like the spectral intensity indicated by the one-dot chain line in FIG. 9B, the LED driver 36 is driven so that the red component light and the blue component light have substantially the same intensity, and each LED of the LED headlamp 11 is turned on. Light.

  Next, at step 102, the ambient light Lx is measured and the routine proceeds to step 104. That is, the detection result is input to the control device 32 by detecting the illuminance around the vehicle by the illuminance sensor 42.

  In step 104, it is determined whether or not each color component of the LED headlamp 11 is to be changed. In this determination, the detected illuminance Lx of the illuminance sensor 42 is other than the illuminance M (M is between the illuminance LL and the illuminance LH corresponding to the intermediate state at first and then stored in step 120 described later) (Lx ≠ M). If the determination is affirmative, the process proceeds to step 106. If the determination is negative, the process proceeds to step 120.

  In step 106, it is determined whether or not the light adaptation state is present. In this determination, it is determined whether or not the detection result of the illuminance sensor 42 is the light adaptation region shown in FIG. 9A. If it is the light adaptation region, the determination is affirmed as the light adaptation state, and the process proceeds to step 108. In the case of the dark adaptation area, the determination is denied as the dark adaptation state and the process proceeds to step 116, and in the case of the intermediate area, the process proceeds to step 112 as the intermediate state.

  In step 108, the color component increase amount (or decrease amount) may be determined, and the process proceeds to step 110. That is, the light emission number or current value of each color LED corresponding to the light adaptation state is read from the map 20.

  In step 110, the LED driver 36 increases the red component (or decreases the blue component) by the LED driver 36 according to the number of light emission or current value of each color LED corresponding to the light adaptation state read from the map 20. Each LED of the illumination lamp 11 is driven, and the process proceeds to Step 120.

  In step 112, the standard component amount of the color component is determined, and the process proceeds to step 114. That is, the number of light emission or current value of each color LED corresponding to the intermediate state is read from the map 20.

  In step 114, each LED of the LED headlamp 11 is driven by the LED driver 36 so as to obtain a standard color component amount according to the light emission number or current value of each color LED corresponding to the intermediate state read from the map 20. The process proceeds to step 120.

  In step 116, an increase amount (or decrease amount) of the color component is determined, and the process proceeds to step 118. That is, the light emission number or current value of each color LED corresponding to the dark adaptation state is read from the map 20.

  In step 118, the blue component is increased (or the red component is increased in the regions other than the central region 12 and the upper region 14) in accordance with the light emission number or current value of each color LED corresponding to the dark adaptation state read from the map 20. Each LED of the LED headlamp 11 is driven by the LED driver 36 (to decrease), and the process proceeds to step 120. That is, the central region 12 and the upper region are irradiated with a larger amount of red component light than other regions. Therefore, when the ambient illuminance is dark, the blue component is controlled to increase (or the red component decreases), but the central region 12 and the upper region 14 have a larger amount of red component light than the other regions. Since it is irradiated, the color and shape recognizability are not impaired, and visibility can be improved. The LED headlamp 11 is controlled so as to increase the blue component light in the region other than the central region 12 and the upper region 14, and as a result, the central component 12 and the upper region 14 emit red component light more than the other regions. The LED headlamp 11 is controlled so as to increase the red component light in the central region 12 and the upper region 14 (for example, to increase the sensitivity of the cone to 550 nm). You may make it do.

  In step 120, the ambient light Lx detected in step 102 is stored as M, and the process proceeds to step 122.

  In step 122, it is determined whether or not the light control switch 40 has been turned off by the occupant. If the determination is negative, the process returns to step 102 and the above-described processing is repeated. finish.

  As described above, in this embodiment, when the visibility characteristic for human colors is in the light adaptation region, the blue component light is more sensitive than the red component light, and in the dark adaptation region, the red component light is used. Because the sensitivity is higher than the blue component light, the lighting control is performed so that the blue component light is larger than the red component light when the ambient illuminance is in the dark adaptation region, and the blue component light is used in the light adaptation region. By controlling the lighting so that the red component light is increased, the front of the vehicle is illuminated with light with high human visibility even if the brightness of the surrounding environment changes. The visibility of the host vehicle from the vehicle can be improved.

  In the dark adaptation area, lighting control is performed so that the blue component light is increased. However, the sensitivity of the cone of the photoreceptor cell is reduced, and the recognizability of the color and the shape is lowered. Since the lighting control is performed so that the central region 12 where traffic light and the like exist and the upper region 14 where traffic signs and the like are present so that the red component light is increased, the recognizability of the color and the shape can be improved.

  In the second embodiment, an example in which an LED is used as a light source as a headlamp has been described. However, the present invention is not limited to this, and a filter is used by applying a light source such as a discharge lamp or a halogen lamp. You may make it change the color of the light which irradiates the vehicle front, and you may make it provide the separate light source which irradiates the center area | region 12 and the upper area | region 14, respectively. Moreover, the presence or absence of execution of control of the LED headlamp in the second embodiment may be switched by the light control switch 40.

  Moreover, in said 1st Embodiment, although the center area | region 12 and the upper area | region 14 demonstrated the headlamp 10 preset so that red component light might increase more than another area | region, like 2nd Embodiment. Alternatively, the control may be performed by the control device 32 or the like.

  Further, in each of the above-described embodiments, the central region 12 and the upper region 14 both emit light forward so that the red component light is larger than the other regions. The light may be irradiated forward so that the red component light is larger than the other regions.

It is a figure which shows the outline vehicle mounting position of the headlamp apparatus concerning 1st Embodiment of this invention. It is a figure for demonstrating the light distribution and center area | region of the headlamp of the headlamp apparatus concerning 1st Embodiment and 2nd Embodiment of this invention. It is a graph which shows the visibility characteristic with respect to a human color. It is a figure for demonstrating the upper area | region of the headlamp of the headlamp apparatus concerning 1st Embodiment and 2nd Embodiment of this invention. It is a figure which shows an example of a structure of the headlamp applicable to the headlamp apparatus concerning 1st Embodiment of this invention. It is a figure for demonstrating the characteristic of a human eye, (A) is a figure which shows an eyeball, (B) is a graph which shows the receptor number and position of the rod and cone of a photoreceptor cell, ( C) is a diagram showing the wavelength sensitivity of the rod and cone. It is a figure which shows the structure of the headlamp of the headlamp apparatus concerning 2nd Embodiment of this invention. It is a block diagram which shows the structure of the headlamp apparatus concerning 2nd Embodiment of this invention. (A) is a graph showing human visual sensitivity characteristics, and (B) is a spectral intensity of light emitted from an LED headlamp in each of a dark adaptation state, a standard state, and a light adaptation state. It is a graph which shows a characteristic. It is a flowchart which shows an example of the flow of the process performed with the control apparatus of the headlamp apparatus concerning 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Headlamp 11 LED headlamp 12 Central area | region 14 Upper area | region 16 LED light source 17 LED lamp 18 Headlamp driver 20 Light source 22 Light source for central area 24 Light source for upper area | region 26 Headlamp lighting circuit 28 LED light source group 30 LED Light source 32 Control device 34 Map 36 LED driver 42 Illuminance sensor

Claims (7)

  A headlight equipped with irradiation means for irradiating light ahead of the vehicle so that the blue component light is included more than the red component light, and the predetermined region in the irradiation region has a larger amount of red component light than other regions. Light equipment.   2. The headlamp according to claim 1, wherein the predetermined area is an upper area that is inclined upward by a predetermined angle with respect to a horizontal plane passing through the irradiating means and is above an inclined surface including the irradiating means. apparatus.   The headlamp device according to claim 1 or 2, wherein the predetermined region is a central region of an irradiation region projected onto a road surface. Changing means for changing the color of the light of the headlamp that irradiates light in front of the vehicle;
Control that irradiates the front of the vehicle with light that contains more blue component light than red component light, and controls the changing means so that a predetermined region in the irradiation region has a larger amount of red component light than other regions. Means,
Headlight device with   The control means is inclined upward at a predetermined angle with respect to a horizontal plane passing through the headlamp, and the upper region above the inclined surface including the headlamp has a red component light irradiation amount higher than other regions. The headlamp apparatus according to claim 4, wherein the changing means is controlled to increase the number.   The said control means controls the said change means so that the irradiation amount of red component light may increase the center area | region of the irradiation area projected on the road surface rather than another area | region. The headlamp device described in 1. Changing means for changing the color of the light of the headlamp that irradiates light in front of the vehicle;
Illuminance detection means for detecting illuminance around the vehicle;
When the detection result of the illuminance detection means is a predetermined low illuminance state, the change means is controlled so that the blue component light is larger than the red component light, and the detection result of the illuminance detection means is predetermined. Control means for controlling the changing means so that the red component light is larger than the blue component light in the case of a high illuminance state;
With
When the control unit controls the changing unit so that the blue component light is larger than the red component light, the predetermined region in the irradiation range of the headlamp is irradiated with the red component light more than the other regions. The headlamp device further controls the changing means so as to increase the amount.

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