Headlight, projection lens, and headlight control method

Abstract

To provide a technology capable of achieving a suitable headlight and the like which suppresses cost, which can improve reliability, and which can secure a light volume in a central part of an irradiation region, and this contributes to "3 health and welfare to everyone", which is a sustainable development target.SOLUTION: A headlight includes: a patterning LED substrate 2 in which a plurality of LED chips is arranged; an LED drive circuit for driving the plurality of LED chips; and a projection lens for projecting the emission light from the LED substrate 2 frontward as a beam. The LED substrate 2 includes: a plurality of LED chips arranged on a plate 61 and for emitting the light from violet to blue wavelength; and a fluorescent body 21 for emitting light of yellow or red and green light with the light of wavelength from purple to blue being excitation light source. Each LED chip is arranged at a predetermined position corresponding to the structure of a front irradiation region so as to achieve light distribution control of a pattern selected from among a plurality of light distribution control patterns containing low beam and high beam.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to lighting technology such as vehicle headlights. [Background technology]

[0002] Headlights (in other words, headlamps) for vehicles such as automobiles include those that use multiple light sources to provide illumination in a desired light distribution pattern. Conventional headlights use semiconductor light source elements such as LEDs (Light Emitting Diodes) as the light sources.

[0003] Vehicle headlights are required to enhance the lighting effect in the area ahead of the vehicle, while preventing dazzle to vehicles in the area ahead of the vehicle, such as preceding and oncoming vehicles. ADB (Adaptive Driving Beam) light distribution control (hereinafter sometimes simply referred to as ADB) has been proposed as one method for achieving light distribution that prevents dazzle. ADB light distribution control is a technology that automatically controls the turning off or dimming of part of the high beam light distribution so as not to dazzle vehicles in the area ahead.

[0004] A headlight using multiple LEDs as light sources has been proposed as a headlight for realizing ADB light distribution control. In this headlight, multiple LEDs each illuminate different areas, and the ADB light distribution pattern is formed by combining these illuminated areas (hereinafter sometimes referred to as "illuminated areas"). In addition, this headlight prevents dazzling the vehicle ahead by selectively turning off or dimming the illumination area where the vehicle ahead is located, and ensures forward visibility by the illuminated illumination area.

[0005] Also, as a headlight for an automobile, there is a so-called bi-function type headlight that projects a low beam (for passing by other vehicles, with the front lights off) and a high beam (for driving, with the front lights off) using the same optical lens.

[0006] An example of the prior art is Japanese Patent No. 5779028 (Patent Document 1). Patent Document 1 describes a light distribution control means for a headlamp that irradiates a light distribution pattern with limited irradiation so as not to cause dazzle. The headlamp is equipped with optical elements arranged in a matrix and capable of controlling the amount of light reflected from the light source, thereby controlling the amount of light for each area in front of the vehicle. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 5779028 Summary of the Invention [Problem to be solved by the invention]

[0008] The current bi-function headlight configuration has many mechanical control parts and optical components such as light guides, etc. Therefore, with this configuration, it is difficult to reduce costs and improve reliability.

[0009] Furthermore, as an example of a headlight technology for realizing ADB, there is a technology for forming an ADB light distribution pattern using optical elements arranged in an array or matrix, as in Patent Document 1. There is also a technology that uses, for example, a micro LED array as the optical element. With this technology, a desired light distribution pattern can be formed in the illumination area in front of the vehicle. However, with such a technology, the amount of light emitted from a light source (e.g., an LED) located in association with the center of the illumination area in front of the vehicle is insufficient, resulting in an insufficient amount of light in the center of the illumination area in front of the vehicle, and it may be difficult to obtain a predetermined amount of light required for, for example, high beam.

[0010] An object of the present invention is to provide a lighting technology that can reduce costs, improve reliability, and ensure the amount of light in the center of the lighting area, thereby realizing a suitable headlight or the like. [Means for solving the problem]

[0011] A representative embodiment of the present disclosure has the following configuration: A headlight of the embodiment includes an LED board on which a plurality of LED chips are arranged, an LED drive circuit for driving the plurality of LED chips on the LED board, and a projection lens arranged forward in a direction perpendicular to the LED board and for projecting light emitted from the LED board as a beam forward, the LED board includes a plate, the plurality of LED chips arranged on the plate and emitting light with wavelengths from purple to blue, and a phosphor arranged on the plate covering the plurality of LED chips and emitting yellow, red, and green light using the light with wavelengths from purple to blue as an excitation light source, each of the plurality of LED chips on the plate is arranged at a predetermined position corresponding to the configuration of a forward illumination area so as to realize light distribution control of a pattern selected from a plurality of light distribution control patterns including low beam and high beam as light distribution control of a beam forward, and the light distribution control of the selected pattern is realized by controlling the turning on and off and the light amount of each LED chip on the LED board from the LED drive circuit. Effect of the Invention

[0012] According to a representative embodiment of the present disclosure, it is possible to realize a suitable headlight or the like that can reduce costs, improve reliability, and ensure the amount of light in the center of the lighting area with respect to lighting technology. Problems, configurations, effects, etc. other than those described above are described in [Mode for carrying out the invention]. [Brief description of the drawings]

[0013] [Figure 1] 1 shows a schematic configuration of a headlight according to a first embodiment. [Diagram 2]2 shows the configuration of a main surface of a patterning LED substrate according to the first embodiment. [Diagram 3] 1 shows a cross-sectional structure of a patterning LED substrate according to a first embodiment. [Figure 4] 1 shows a cross-sectional configuration of a patterning LED substrate according to a modified example of the first embodiment. [Diagram 5] 2 shows the configuration of a projection lens according to the first embodiment. [Figure 6] 1 shows a configuration of an LED drive circuit according to a first embodiment. [Figure 7] 2 shows a configuration example of an LED device of the LED chip according to the first embodiment. [Figure 8] The following shows the structure of the regulations governing low beams for right-hand traffic. [Figure 9] 2 shows a configuration of a first pattern (normal low-beam light distribution control) according to the first embodiment. [Figure 10] 1 shows a configuration of a second pattern (normal high beam light distribution control) according to the first embodiment. [Figure 11] 1 shows a configuration of a third pattern (high beam+ADB light distribution control) according to the first embodiment. [Figure 12] 13 shows a configuration of a fourth pattern (high beam+variable light distribution width control) according to the first embodiment. [Figure 13] 13 shows a configuration of a fifth pattern (high beam+variable light distribution center control) according to the first embodiment. [Figure 14] 13 shows a configuration of a sixth pattern (lighting when cornering) according to the first embodiment. [Figure 15] 13 shows the configuration of a seventh pattern (white line emphasis in rainy weather) according to the first embodiment. [Figure 16] 1 shows a configuration example of light distribution control using an LED array in a comparative example to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same parts are generally given the same reference numerals, and repeated explanations will be omitted. In the drawings, the representation of components may not represent the actual position, size, shape, range, etc., in order to facilitate understanding of the invention.

[0015] [Comparative Example] FIG. 16 is an explanatory diagram of a headlight technology of a comparative example with respect to the first embodiment. (A) of FIG. 16 shows an outline of an ADB unit with an LED array constituting a headlight of the comparative example. This ADB unit has an LED array 1601 arranged on the main surface of a substrate. The LED array 1601 has a plurality of LED devices 1602 arranged vertically and horizontally in a matrix. The enlarged portion in (A) shows a portion of 4×12 LED devices 1602. Note that in (A), each LED device 1602 is shown as a square of the same size, but in reality, each LED device 1602 may be arranged in a different size or shape. The turning on / off of each LED device 1602 can be controlled by an LED drive circuit.

[0016] FIG. 16B is a schematic diagram showing an example of the configuration of an illumination area in front of a vehicle based on the configuration of the LED array 1601 in FIG. 16A. The line hh corresponds to the horizontal line. For ease of understanding, an example of a vehicle lane 1604 and a beam area (corresponding to the zone in FIG. 8) are also shown. The illumination area 1603 is configured as a grid corresponding to the LED array 1601. Each square in the grid corresponds to an illumination area by each LED device 1602.

[0017] A headlight of the comparative example using such an LED array 1601 realizes a light distribution pattern as ADB light distribution control in an illumination area 1603 by controlling the light emission of each LED device 1602 of the ADB unit. An example of an ADB light distribution pattern is one in which, when there is an oncoming vehicle ahead in an oncoming lane 1605 to the left of the vehicle's lane 1604, an area 1607 corresponding to the oncoming vehicle is turned off or dimmed. A number of LEDs (e.g., 9 LEDs in a 3×3 arrangement) associated with the area 1607 are turned off.

[0018] However, in such a headlight of the comparative example, since the LED array 1601 in which the LED devices 1602 are uniformly arranged is used, the amount of illumination may be insufficient in the center of the illumination area 1603 (e.g., area 1608). Due to this insufficiency, the requirements for a high beam or the like may not be met, or a suitable high beam or the like may not be achieved.

[0019] <Embodiment 1> The headlight according to the first embodiment of the present disclosure will be described with reference to Figs. 1 to 15.

[0020] The headlight of the first embodiment shown in Fig. 1 etc. includes a patterned LED substrate 2 having a plurality of LED chips that emit blue light arranged on a plate 61, and phosphor 21 that emits yellow or red and green light using purple to blue wavelength light from the LED chips as an excitation light source and that is applied to the plate 61 (Fig. 2). The positions of the plurality of LED chips (LED chips 22 to 42) on the plate 61 of the patterned LED substrate 2 (in other words, the main surface, a plane perpendicular to the optical axis) are designed in advance according to the design of a desired light distribution pattern in the illumination area in front of the vehicle.

[0021] Furthermore, the patterned LED substrate 2 has shielding plates (shielding plates 43 to 58) arranged on the plate 61 between the LED chips (between the LED chips at predetermined positions) as boundaries for limiting the excitation range of the phosphor 21 and shielding the light emission of the LED chips. With this configuration, the headlight of the first embodiment controls the amount of light emitted from each LED chip, and sets low beam, high beam, and high beam with ADB light distribution control on the plate 61 as light distribution control (in other words, light distribution pattern) for the illumination area in front of the vehicle. The headlight of the first embodiment realizes light distribution of a desired light distribution pattern that is controlled and selected by projecting the emitted light from the patterned LED substrate 2, in which the light distribution on the plate 61 is set, as a beam toward the front of the vehicle by the projection lens 1 (FIG. 1).

[0022] The arrangement of the LED chips and the shielding plates as the boundaries in the patterned LED substrate 2 can be freely set according to the design of the light distribution pattern in the illumination area in front of the vehicle. As an example of the setting and design of the light distribution pattern, the shielding plates are placed at positions corresponding to the left and right white lines of the lane in which the vehicle is traveling on the main surface of the patterned LED substrate 2 corresponding to the illumination area. In the case of this light distribution pattern, it is possible to control the light distribution in the area of ​​the left and right white lines (Fig. 15).

[0023] According to the configuration of the headlight of the first embodiment, the light distribution ahead of the vehicle is controlled to mask (in other words, selectively turn off or dim) the beam toward oncoming vehicles, etc., so as not to dazzle the drivers of oncoming vehicles, etc., and patterns such as low beam, high beam, and high beam with ADB can be switched. Therefore, the headlight of the first embodiment can achieve various functions such as low beam, high beam, glare prevention by ADB, and white line emphasis, all in one headlight unit, without using multiple mechanical parts or a large number of optical elements (e.g., an LED array).

[0024] Furthermore, according to the configuration of the headlight of the first embodiment, when it is desired to control the light distribution toward the road shoulder side rather than the oncoming vehicle according to the ADB control and the distance between the vehicle and the oncoming vehicle, when it is desired to brightly illuminate the white lines on the road in rainy weather, etc., a light distribution pattern corresponding to the case (corresponding mode) can be realized. Therefore, according to the first embodiment, it is possible to improve the driver's visibility of important areas, enabling safer driving.

[0025] [Headlight] Fig. 1 is a perspective view showing a schematic configuration of a headlight of the first embodiment. The headlight of the first embodiment includes a heat sink 3, a patterning LED substrate 2 provided on the heat sink 3, an LED drive circuit 4 electrically connected to the patterning LED substrate 2, and a projection lens 1 disposed in front of a main surface 2A of the patterning LED substrate 2 (Z direction in Fig. 1). These components are fixed to a housing (not shown) of the headlight in a predetermined positional relationship. This headlight projects light emitted from the patterning LED substrate 2 as a beam by the projection lens 1 in the direction forward of the vehicle (indicated by an arrow).

[0026] For the sake of explanation, X, Y, and Z may be used as directions and a coordinate system. In FIG. 1, the Z axis is the direction of the headlight illumination (beam), and is the direction of the optical axis of the light emitted (emitted light) from the patterning LED substrate 2. The X axis and the Y axis are directions perpendicular to the Z axis, and are two orthogonal directions that constitute the main surface 2A (plane on which multiple LED chips are arranged) of the patterning LED substrate 2. In particular, the X axis corresponds to the horizontal direction, the lateral direction within the main surface 2A, and the Y axis corresponds to the vertical direction, the longitudinal direction within the main surface 2A.

[0027] The heat sink 3 is disposed in contact with the rear side of the main surface 2A of the patterning LED substrate 2 in order to dissipate heat from the patterning LED substrate 2.

[0028] The patterning LED substrate 2 is an LED substrate in which a plurality of LED chips are arranged at predetermined positions on the main surface 2A (on the corresponding plate 61) to form a predetermined pattern shape, as shown in Fig. 2 described later. Emission (emitted light) including emission from each LED chip of the patterning LED substrate 2 has an optical axis in the Z direction shown by the dashed line in Fig. 1 and travels toward the projection lens 1.

[0029] The LED driving circuit 4 is mounted on a substrate separate from the patterning LED substrate 2, and is electrically connected to the patterning LED substrate 2 through wiring (which may be implemented on a flexible printed circuit board, for example). As a modified example, the LED driving circuit 4 may be integrally mounted with the patterning LED substrate 2.

[0030] The same standard can be applied to the two headlights installed on the left and right sides of the front of the vehicle.

[0031] [Patterning LED substrate] Fig. 2 shows an XY plan view of the main surface 2A of the patterning LED substrate 2. In Fig. 2, the main surface 2A of the patterning LED substrate 2 is shown as a plan view from back to front in the Z direction (in other words, the front-rear direction) of Fig. 1, in order to correspond to a person viewing the illumination area in front of the vehicle from inside the vehicle.

[0032] As shown in FIG. 2, the patterned LED substrate 2, when viewed from the main surface 2A, has a plate 61, LED chips 22, 23, ..., 41, 42 as a plurality of LED chips arranged at predetermined positions in a predetermined pattern shape on the plate 61, a phosphor 21 formed in a predetermined area so as to cover the plurality of LED chips, and shielding plates 43, 44, ..., 57, 58 as a plurality of shielding plates arranged between predetermined spaces among the plurality of LED chips.

[0033] In this example, the plate (substrate) 61 is a rectangular substrate that is long horizontally in the X direction. This long horizontal length corresponds to the roughly long horizontal length of the illumination area (area to be irradiated with the beam) in front of the vehicle.

[0034] The multiple LED chips can be broadly divided into nine LED chips (first LED chip group) arranged on a first line 2B extending in the X-direction as indicated by a dotted line, namely LED chips 22, 23, 24, 25, 26, 27, 28, 29, and 30, and twelve LED chips (second LED chip group) arranged on a second line 2C extending in the X-direction as indicated by a dashed line, namely LED chips 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, and 42.

[0035] In the first LED chip group, an LED chip 26 is disposed at a central position indicated by a dashed line. The central position corresponds to the center of the headlight in the X direction. Four LED chips (22 to 25, 27 to 30) are disposed symmetrically on each side of the central LED chip 26, at predetermined intervals and predetermined positions.

[0036] In the second LED chip group, the LED chip 35 is arranged at the center position indicated by the dashed line. On the right side of the central LED chip 35, seven LED chips (36-42) are arranged at predetermined positions with a predetermined interval. On the left side of the central LED chip 35, three LED chips (32-34) are arranged at predetermined positions with a predetermined interval. Also, one LED chip 31 is arranged near the lower left of the central LED chip 35. In this way, in the second LED chip group, a plurality of LED chips are arranged asymmetrically. This arrangement corresponds to the difference in the shape of the area to be illuminated on the left and right in the illumination area in front of the vehicle, as will be described later (FIG. 8). The density and number of the LED chips on the right side and the LED chips on the left side in the second LED chip group are also different, and the density and number are larger on the right side.

[0037] The phosphor 21 is formed in a predetermined area, which in this example is a convex area in the Y direction, so as to cover all the LED chips. This convex shape corresponds to the general convex shape of the illumination area in front of the vehicle. The area that protrudes above the second line 2C generally corresponds to the illumination area above the horizontal line described below (FIG. 8).

[0038] The multiple shielding plates include obliquely shaped (obliquely relative to the X-axis and Y-axis) shielding plates 43, 44, 45, and 46 arranged near the left and right end LED chips 22 and 30 relative to the first LED chip group, and shielding plates 47, 48, 49, and 50 extending in an oblique shape arranged near the left and right LED chips 25 and 27 relative to the central LED chip 26.

[0039] The shielding plates 43, 44, 45, and 46 near the left and right ends are formed to correspond to the pattern at the time of cornering described later. In detail, the shielding plate at the left end includes the shielding plate 43 arranged to extend obliquely from the upper left corner of the phosphor 21 area toward the center on the upper side in the Y direction with respect to the LED chip 22 at the left end, and the shielding plate 44 arranged to extend obliquely from the lower left corner of the phosphor 21 area toward the center on the lower side in the Y direction with respect to the LED chip 22 at the left end. The extension of the shielding plates 43 and 44 is to about the middle between the LED chip 22 and the adjacent LED chip 23. Similarly, the shielding plate at the right end includes the shielding plate 46 arranged to extend obliquely from the upper right corner of the phosphor 21 area toward the center on the upper side in the Y direction with respect to the LED chip 30 at the right end, and the shielding plate 45 arranged to extend obliquely from the lower right corner of the phosphor 21 area toward the center on the lower side in the Y direction with respect to the LED chip 22 at the right end. The shielding plates 45 and 46 extend to approximately the middle between the LED chip 30 and the adjacent LED chip 29 .

[0040] The left and right shielding plates 47, 48, 49, and 50 are formed to correspond to the patterns of the left and right white lines described later. Between the central LED chip 26 and the LED chip 25 adjacent to it on the left, a shielding plate 48 is arranged, which extends obliquely from the lower left to the upper right toward the center of the area. Between the LED chip 25 adjacent to it on the left and the LED chip 24 adjacent to it on the further left, a shielding plate 47 is arranged on the upper left side of the shielding plate 48, which extends obliquely from the lower left to the upper right toward the center of the area. These two shielding plates 47 and 48 have a shape corresponding to the white line area on the left side of the own lane in the illumination area. The LED chip 25 is arranged in the left white line area sandwiched between the two shielding plates 47 and 48.

[0041] Similarly, a shielding plate 49 is disposed between the central LED chip 26 and the adjacent LED chip 27 on the right, extending obliquely from the lower right to the upper left toward the center of the area. In addition, a shielding plate 50 is disposed between the adjacent LED chip 27 on the right and the LED chip 28 on the further right, on the upper right side of the shielding plate 49, extending obliquely from the lower right to the upper left toward the center of the area. These two shielding plates 49, 50 have a shape corresponding to the white line area on the right side of the own lane in the illumination area. The LED chip 27 is disposed in the area of ​​the white line on the right side, sandwiched between the two shielding plates 49, 50.

[0042] In addition, the multiple shielding plates include shielding plates 52, 53, 54, 55, 56, 57, 58 extending in the Y direction and arranged to separate each LED chip from the central LED chip 35 to the LED chip 42 at the right end, and shielding plate 51 arranged to separate the area from the central LED chip 35 to the LED chips 36, 37 on the right side and the LED chips 31, 34 on the left side.

[0043] More specifically, the shielding plate 51 is composed of three parts: a shielding plate portion arranged in the X direction below the LED chips 35, 36, and 37 in the Y direction; a shielding plate portion arranged in the X direction above the left-side LED chip 34 in the Y direction; and a shielding plate portion arranged diagonally between the central LED chip 35 and the lower left LED chip 31 so as to connect these shielding plate portions.

[0044] With respect to the LED chips on the right side from the central LED chip 35, the three shielding plates 52, 53, and 54 extending in the Y direction extend to and stop at the shielding plate 51. In addition, the four shielding plates 55, 56, 57, and 58 extending in the Y direction extend to and stop at the oblique shielding plate 50.

[0045] [Patterning LED substrate] Fig. 3 shows an XZ plan view as a cross-sectional view of the patterned LED substrate 2 of Fig. 2 taken along line AA. In the Z direction, silicon grease 62 for improving thermal conductivity is applied to the surface of the heat sink 3, and a plate 61 is disposed via the silicon grease 62. Metal foil wiring (e.g., metal foil wiring 63-68) for connecting LED chips and resist 60 are formed on the surface of the plate 61. LED chips (e.g., LED chips 25, 26, 27) are connected on the metal foil wiring.

[0046] For example, shielding plates 48, 49 are formed between LED chips 25, 26, 27 so as to stand in the Z direction. The shielding plates 48, 49 are formed so as to stand like walls in the Z direction from the surface of resist 60 to surface 21a of phosphor 21. In the configuration example of FIG. 3, the height of the shielding plates 48, 49 is the same as thickness 301 of phosphor 21. All the shielding plates are formed to the same height as surface 21a of phosphor 21.

[0047] The characteristics of light emission from the LED chip will be described using the illustrated LED chip 27 as an example. Light emission 70 from the LED chip 27 is blue light as LED excitation light. Light emission 76 from the LED chip 27 is also blue light as LED excitation light. For the sake of explanation, the light emission is illustrated as two separate parts, light emission 70 and light emission 76. One of the blue lights, light emission 70, excites the phosphor 21 and generates yellow light as light emission 73. The yellow light light emission 73 is emitted forward (Z direction) from the surface 21a of the phosphor 21. The other blue light light, light emission 76, is a component that passes through the phosphor 21 as it is and is emitted forward from the surface 21a of the phosphor 21. In this way, a part of the light emission from the LED chip is converted into yellow light by excitation and emitted, and the other part is emitted as blue light.

[0048] The light emitted forward from the surface 21a of the phosphor 21 is a combination of these two types of light emissions 73, 76, and the combination of blue light and yellow light becomes white light 302. This white light 302 becomes the light emitted from the patterning LED substrate 2. Note that this white light 302 is designed to satisfy the requirements for luminous intensity, such as low beam, stipulated by regulations described below.

[0049] Similarly, there is light emission from the LED chip 27 in a forward oblique direction. For example, there is light emission 72 and light emission 78 having a certain divergence angle. When light emission 72 is not blocked by a shielding plate, it becomes light emission 75, which is yellow light, upon excitation and is emitted from surface 21a of phosphor 21. When light emission 78 is not blocked by a shielding plate, it is emitted as it is from surface 21a of phosphor 21 as blue light.

[0050] Also, there are light emissions 71 and 77 having a certain divergence angle. The light emission 71 becomes light emission 74, which is yellow light, when excited. These light emissions 74 and 77 are shielded by the shielding plate 49. The shielding plate 49 is disposed at a predetermined position between the central LED chip 26 and the LED chip 27 on the right side thereof. The shielding plate 49 is disposed at a first distance from the LED chip 26 and at a second distance from the LED chip 27. Note that there is also a shielding plate 50 on the right side of the LED chip 27 as shown in FIG. 2, but it is omitted in FIG. 3.

[0051] The shielding plate blocks light emitted from the LED chip. For example, the shielding plate 49 blocks both light emission 74 (yellow light) and light emission 77 (blue light) from the LED chip 27. As a result, for example, light emitted from the LED chip 27 in FIG. 2 mainly illuminates the right-side white line corresponding to the area divided by the left shielding plate 49 and the right shielding plate 50 in the forward illumination area. The light emitted from the LED chip 27 is restricted in divergence in response to the shielding by the shielding plate 49, so that the amount of light reaching the area corresponding to the vehicle's lane including the LED chip 26 in FIG. 2 is reduced.

[0052] Similarly, light emitted from, for example, the left LED chip 25 is shielded by the right shielding plate 48 and the left shielding plate 47 in Fig. 2. As a result, light emitted from the LED chip 25 in Fig. 2 mainly illuminates the left white line corresponding to the area partitioned by the left shielding plate 47 and the right shielding plate 48.

[0053] Similarly, light emitted from the central LED chip 26 is blocked by the right shielding plate 49 and the left shielding plate 48. The diagonal dashed lines in the figure indicate the divergence angle at which the light emitted from the LED chip 26 is not blocked by the shielding plates 49, 48, in other words, the effective excitation range and divergence range limited by the shielding plates. As a result, the light emitted from the LED chip 26 in FIG. 2 mainly illuminates the vehicle lane corresponding to the area divided by the left shielding plate 48 and the right shielding plate 49.

[0054] Similarly, the other LED chips in FIG. 2 mainly illuminate the area divided by the shielding plate. As shown in FIG. 2, the area divided by the shielding plate may have various areas, such as one LED chip, two or more LED chips, or no LED chip. In the configuration example of FIG. 2, the space (the area of ​​the corresponding phosphor 21) is not completely divided by the shielding plate, but is roughly divided into a plurality of spaces (corresponding areas). The light emitted from a certain LED chip may diverge to the outside through a portion where there is no shielding plate. The diverged light also forms an illumination area. For example, the shielding plate 49 extends from a position slightly away from the lower side of the area of ​​the phosphor 21 in FIG. 2, diagonally upward to the left, toward the LED chip 35 at the center of the second line 2C, to a position slightly away so as not to contact the shielding plate 51. The light emitted from the LED chip 26 is emitted with the Z direction as the optical axis and diverges all around within the XY plane in Figure 2, but some of the light is blocked by the shielding plate 49, etc., and the other part is emitted forward so as to diverge outward from places where there is no shielding plate 49, etc.

[0055] Without being limited to this, as a modified example, the space above the plate 61 may have an area that is completely partitioned by a shielding plate in the XY plane (in other words, a closed area).

[0056] The division into multiple regions in the lighting area in front of the vehicle in Fig. 2 is designed by the position of each LED chip, the position, shape, height, etc. of each shielding plate, as described above. Note that the configuration of the physical division into multiple regions by shielding plates, etc. on the surface of plate 61 in Fig. 2 and the configuration of multiple regions (areas actually irradiated with beams, distribution of luminous intensity) in the lighting area in front of the vehicle are not strictly the same due to forward divergence, but they correspond to each other, and the configuration of the lighting area is similar to the configuration by shielding plates, etc.

[0057] Specifically, the optical shielding property of the shielding plate may be absorption, reflection, or other property. The shielding property may be a property that realizes a function of restricting the divergence of light emitted from the LED chip (among which, an LED device described later), that is, the spread in the lateral direction (XY plane) with respect to the direction (Z axis) toward the front of the vehicle. The material and manufacturing method of the shielding plate are not limited, and it may be formed, for example, of a base material coated with a black film (in other words, a light-shielding film). Alternatively, it may be formed as a shielding plate by processing (e.g., photo-curing) a part of the phosphor 21.

[0058] 3 in the first embodiment, the shielding plate has a height / thickness 301 that stands from the resist 60 on the plate 61 to the surface 21a of the phosphor 21 in the Z direction. That is, the thickness of this shielding plate is the same as the thickness of the phosphor 21.

[0059] The advantage of the configuration example of the shielding plate in Fig. 3 is that it is possible to clearly divide and limit the lighting area in front of the vehicle into multiple areas by ensuring the height and thickness 301. However, in the case of this configuration example, when looking toward the headlights from the front, that is, when viewing the lighting by the beam, there is a possibility that the area where the shielding plate is located will be seen as a dark line, that is, a part that appears relatively dark in the lighting.

[0060] [Modification: Shielding plate] FIG. 4 similarly shows the configuration of a modified example of the shielding body of FIG. 3. FIG. 4 has shielding plates 81 and 82 as a difference from FIG. 3. The shielding plates 81 and 82 are formed to stand from the resist 60 on the plate 61 in the forward Z direction at a predetermined height 401 to a position of a predetermined distance (in other words, a gap) 80 in front of the surface 21a of the phosphor 21. That is, the shielding plates 81 and 82 are low-profile shielding plates formed at a height 401 lower than the height 301 of the shielding plates 48 and 49 of FIG. 3. The height 401 of the shielding plates 81 and 82 of FIG. 4 and the distance 80 from the front end (highest position) to the surface 21a of the phosphor 21 are designed to appropriate values ​​according to parameters such as the position and interval of the LED chips, the position and width of the shielding plates, and the resolution of the projection lens 1. That is, the values ​​of the height 401 and the distance 80 are designed to be values ​​that can sufficiently ensure the limit of the range of divergence of light emitted from the LED chips.

[0061] 4, for example, oblique light emission 83 and light emission 85 (similar to light emission 74 and light emission 77 in FIG. 3) from LED chip 27 are not blocked by shielding plate 82 and are emitted from surface 21a of phosphor 21 through gap 80 on shielding plate 82. Similarly, oblique light emission 85 and light emission 86 from LED chip 27 are not blocked by shielding plate 82 and are emitted from surface 21a of phosphor 21 through gap 80 on shielding plate 82.

[0062] In the configuration example of Fig. 4, the restriction of the divergence of the light emitted from the LED chip by the shielding plate is weaker than in the configuration example of Fig. 3, the degree of divergence of the light emitted from the LED chip is greater, and each lighting area is wider. The advantage of the configuration example of the shielding plate in Fig. 4 is that since the shielding plate is not exposed from the phosphor 21, when looking toward the headlight from the front, the part of the shielding plate is less visible as a dark line in the light.

[0063] As another modified example of the shielding plate, a configuration example in which a part (the highest part) of the shielding plate is exposed from the surface 21a of the phosphor 21 to a position at a predetermined distance forward is also possible.

[0064] [Projection lens] FIG. 5 shows a cross-sectional view in the XZ plane as the configuration of the projection lens 1 in the first embodiment. The projection lens 1 has optical characteristics for realizing a predetermined beam projection performance of the headlight in the first embodiment. Specifically, the projection lens 1 in the first embodiment has at least a resolution specification. As a specific example, this resolution (MTF) is 3 lp / mm (unit: line pairs per millimeter). The resolution of this projection lens 1 needs only to realize a resolution of 16% or more for light emitted forward (in the Z direction) from the patterning LED substrate 2 (in other words, emitted light).

[0065] Specifically, the projection lens 1 in FIG. 5 has a convex lens 91, which is a first lens arranged on the side where light emitted from the aforementioned multiple LED chips on the main surface of the patterning LED substrate 2 enters as incident light, in the Z direction, and a concave lens 90, which is a second lens arranged on the exit side of the convex lens 91. These two lenses are made of, for example, polycarbonate. Both the convex lens 91 and the concave lens 90 have aspheric shapes on the entrance surface and exit surface. This aspheric shape is a shape for realizing correction such as aberration correction by the projection lens 1, that is, correction for forming a suitable beam in front of the vehicle.

[0066] The shape and resolution specifications of this projection lens 1 are optimally designed to project light emitted from the aforementioned characteristic patterning LED substrate 2 forward of the vehicle. By placing such a projection lens 1 at a position a predetermined distance forward of the aforementioned patterning LED substrate 2 and using them in combination, a suitable illumination area can be formed by the headlight of the first embodiment.

[0067] [Patterning LED substrate and LED drive circuit] As described above, in the headlight of the first embodiment, the multiple LED chips of the patterned LED substrate 2 are arranged at predetermined positions corresponding to the illumination area in front of the vehicle (particularly multiple areas designed to configure various light distribution patterns), unlike a simple LED array (comparative example of FIG. 16). Also, in the headlight of the first embodiment, multiple shielding plates are arranged at predetermined positions and shapes corresponding to the illumination area in front of the vehicle.

[0068] Furthermore, in the headlight of the first embodiment, the multiple LED chips on the patterned LED substrate 2 are not designed to have the same amount of light emitted from each LED chip, but are designed so that each LED chip has a different amount of light emitted in accordance with the illumination area in front of the vehicle. Also, the headlight is designed so that the amount of light emitted from each LED chip can be changed by the LED drive circuit 4 according to the light distribution pattern. This viewpoint will be described below.

[0069] [LED drive circuit] FIG. 6 shows the configuration of the LED driving circuit 4 and the like. FIG. 6 mainly shows an example of the internal functional block configuration of the LED driving circuit 4 electrically connected to a vehicle controller 102 (for example, an electronic control unit: ECU) of a vehicle equipped with the headlight of the first embodiment through wiring and a terminal 108. The LED driving circuit 4 is also connected to an on-board power supply 100 of the vehicle through a terminal 107. The on-board power supply 100 is connected to a ground 101. The LED driving circuit 4 is also electrically connected to a plurality of LEDs (LED chips 22 to 42) of the patterning LED substrate 2 through terminals 109, 110, 111, etc. on the LED driving circuit 4 side, wiring, and terminals 104, 105, 106, etc. on the patterning LED substrate 2 side. The plurality of LEDs are connected to the ground 101 through a terminal 103.

[0070] The LED driving circuit 4 includes a microcontroller 126, a regulator 125, a switch 124, a boost converter 128, a reference voltage circuit 127, and a plurality of LED PWM driving units 112, 113, and 114. Each LED PWM driving unit is a driving circuit provided in association with a specific LED chip.

[0071] The LED PWM drive unit includes terminals 115, 116, 117, 109, a comparator (differential amplifier) ​​133, a step-down control circuit 129, a switch (ON / OFF switch) 130, a current detection circuit 131, a current-voltage conversion circuit 132, and the like.

[0072] The microcontroller 126 includes circuits such as a processor and a memory. Alternatively, a memory or an external storage device provided outside the microcontroller 126 may be used. The memory stores setting information for driving and controlling the multiple LED chips of the patterning LED substrate 2, for example, in the form of table data.

[0073] This setting information is information for selecting a pattern of beam light distribution control (also referred to as a light distribution pattern) that corresponds, for example, one-to-one to the mode indicated by the input information based on a command from the vehicle controller 102 (or another part) or various vehicle information. That is, in the table of this setting information, for example, the correspondence between the mode and the pattern is defined. The details of this setting information are not limited.

[0074] The above-mentioned modes are descriptive terms, but they represent the conditions of the vehicle and its surroundings at that time, or the lighting state that the vehicle controller 102 wants to achieve for lighting in front of the vehicle. The modes represent, for example, areas in which directions are to be brightened and areas in which directions are to be darkened by ADB light distribution control or the like, such as a mode in which the lights are turned off in front of the oncoming lane to protect against fenders, a mode in which the area ahead of the right turn is brightened to warn drivers when turning right, and a mode in which the white lines are brightened in rainy weather.

[0075] The above modes are associated with specific light distribution patterns, for example, one-to-one. The light distribution pattern is a pattern that specifies which specific areas in the illumination area in front of the vehicle should be illuminated brightly and which specific areas in the illumination area in front of the vehicle should be illuminated darkly, and specifies which LED chips should be turned on or off and the amount of light each LED chip should emit. The microcontroller 126 selects and determines the light distribution pattern at that time based on the setting information in the memory in accordance with input information (e.g., mode designation) from the vehicle controller 102.

[0076] Although the mode and the light distribution pattern are separated, they may be defined as the same thing, and the same effect can be obtained. In the case where they are defined as the same thing, the vehicle controller 102 specifies the light distribution pattern to the microcontroller 126.

[0077] Examples of information (referred to as vehicle information) regarding the vehicle surroundings and the like that can be grasped by the vehicle controller 102 are shown below. Based on such vehicle information, the vehicle controller 102 can determine what mode should be set for the headlights.

[0078] Examples of vehicle information include speed information, gear information, steering wheel angle information, lamp illumination information, external light information, distance information, infrared information, engine ON / OFF information, camera image information (inside and outside the vehicle), acceleration gyro information, GPS information (including current time), navigation information, vehicle-to-vehicle communication information, and road-to-vehicle communication information.

[0079] Alternatively, the headlight microcontroller 126 may determine the mode or light distribution pattern based on acquired vehicle information.

[0080] In the setting information of the microcontroller 126, each mode and each light distribution pattern is identified by, for example, an ID. Each light distribution pattern can specify the on / off and light amount for each LED chip at each position. The LED chip at each position is also identified by an ID (LED chip ID).

[0081] As described later, the number of series of LED devices constituting the LED chip may differ for each LED chip (22 to 42) at each position on the patterning LED substrate 2. In response to such a configuration, the setting information of the light distribution pattern of the microcontroller 126 also includes control information on how to perform step-down control (described later) in each LED PWM drive unit so that the light amount of the LED chip at each position can be variably specified within a predetermined range.

[0082] In Fig. 6, a power supply voltage is supplied from an on-board power supply 100 to an LED drive circuit 4 through a terminal 107. This power supply voltage is supplied to a microcontroller 126 through a regulator 125, and in a supply state, the microcontroller 126 automatically starts up. The power supply voltage is supplied to a step-up converter 128 through an on-state of a switch 124, and the step-up converter 128 steps up the power supply voltage to generate a common power supply voltage for a plurality of LED chips and an LED PWM drive unit. The common power supply voltage is supplied to each LED PWM drive unit (particularly a step-down control circuit 129) through a terminal 117, etc.

[0083] Furthermore, a reference voltage is supplied from the reference voltage circuit 127 to each LED PWM driver (particularly the comparator 133) via the terminal 116 and the like.

[0084] When the microcontroller 126 controls the headlights to have a certain light distribution pattern, it transmits a drive control signal corresponding to that light distribution pattern to each LED PWM driver via the terminal 115 or the like.

[0085] The LEDPWM driver is a circuit portion that drives the associated LED chip with a pulse width modulated (PWM) current (in other words, an LED drive current). For example, the LEDPWM driver 112 outputs an LED drive current from a terminal 109 by controlling the drive of an internal circuit according to a drive control signal input through a terminal 115. The LED drive current is supplied to the LED chip 22 through a terminal 104, and one or more LED devices constituting the LED chip 22 (in the case of the LED chip 22, one LED device 701 as shown in FIG. 7A) are driven, causing the LED chip 22 to emit light.

[0086] In each LED PWM driver, a switch 130 (for example, composed of a MOS switch) is turned ON / OFF by the drive control signal. Also, a comparator 133 receives the drive control signal as a control input, a reference voltage as a positive input, and a detection voltage after IV conversion from the LED drive current as a negative input, and outputs a difference voltage.

[0087] The step-down control circuit 129 receives the common power supply voltage and the differential voltage. The step-down control circuit 129 outputs a voltage (also referred to as a stepped-down voltage) obtained by stepping down the common power supply voltage in accordance with the differential voltage. When the switch 130 is in an ON state, the stepped-down voltage is output from an output terminal (terminal 109, etc.) via a current detection circuit 131.

[0088] The LED drive current output from the LED PWM drive unit (terminal 109, etc.) is a current signal (in other words, a PWM signal) that includes PWM on-periods and off-periods according to the switching control of switch 130 between the on state and the off state. Each LED chip is switched on and off according to the LED drive current. As a result, the amount of light emitted from the LED chip is basically determined according to the length of the PWM on-period. The amount of light emitted from the LED chip is also determined according to the configuration of the number of series of LED devices described below (FIG. 7).

[0089] The processor of the microcontroller 126 executes processing according to the program read onto the memory while appropriately using resources such as memory. This realizes a predetermined function, processing unit, etc. The processor is composed of, for example, a semiconductor device such as a CPU. The processing is not limited to software program processing, but can also be implemented by a dedicated circuit. The dedicated circuit can be an FPGA, an ASIC, a CPLD, etc. The program may be installed as data in advance, or distributed as data from a program source. The program source may be a server on a communication network, or a non-transient computer-readable storage medium (for example, a memory card). Various data and information are composed of, for example, a structure such as a table, but are not limited to this. Expressions such as identification information, identifiers, IDs, names, and numbers are mutually interchangeable.

[0090] [LED chip] FIG. 7 shows an example of the configuration of one or more LED devices in an LED chip. FIG. 7(A) shows a case where a certain LED chip, for example the LED chip 22 near the left end of FIG. 2, is configured with one LED device 701. The number of series of this LED chip is 1. FIG. 7(B) shows a case where a certain LED chip, for example the LED chip 25 in the left white line area of ​​FIG. 2, is configured with three LED devices 701 connected in series. The number of series of this LED chip is 3. FIG. 7(C) shows a case where a certain LED chip, for example the LED chip 31 in FIG. 2, is configured with four LED devices 701 connected in series. The number of series of this LED chip is 4. Each LED chip has a basic light emission amount according to the number of series, and the larger the number of series, the greater the basic light emission amount.

[0091] In addition, when one LED chip is composed of multiple LED devices 701 as in (B) and (C), an example of implementation is a configuration in which multiple LED devices 701 are connected in series in a direction (Z direction) perpendicular to the direction constituting the main surface (XY plane) of the patterned LED substrate 2 as shown in Fig. 2. As long as a predetermined amount of light emission can be secured for each LED chip when viewed in a plan view on the main surface, the configuration is not limited to such a vertical series connection configuration.

[0092] The number of LED devices 701 (corresponding number of series) as described above is designed according to the position of the multiple (for example, a total of 21 in FIG. 2) LED chips (22-42) on the main surface of the patterning LED substrate 2. As described above, multiple LED chips and multiple shielding plates are arranged on the main surface of the patterning LED substrate 2 in FIG. 2 in correspondence with the configuration of the illumination area in front of the vehicle (the configuration of multiple light distribution patterns described later). The basic light emission amount of the LED chips at each position is designed in correspondence with the configuration of the illumination area, and the number of series may differ for each position.

[0093] Specifically, in the first embodiment, in order to ensure the amount of illumination in the center in the configuration of the illumination area in front of the vehicle, the multiple LED chips on the patterned LED substrate 2 are designed to have different numbers of series so that the basic light emission amount of the LED chip is greater in the center than in the peripheral area. The center refers to a portion such as the area 1608 in the comparative example of FIG. 16, and in FIG. 2, it corresponds particularly to the vicinity of the position of the LED chip 35 and the LED chip 31 on the second line 2C. The LED chip 35 and the LED chip 31, and certain LED chips in the vicinity thereof, such as the LED chips 36, 37, and the LED chip 34, are designed as LED chips with the largest number of series, for example, the configuration of (C) in FIG. 7. The LED chips located farther away from the LED chip 35 are designed as LED chips with a smaller number of series. For example, the LED chips 25 and 27 in the white line area are configured with a number of three series, as shown in (B) in FIG. 7. For example, the LED chips 22 and 30 near the left and right ends are configured as at least one LED device 701 as shown in Fig. 7A. The configuration of the LED devices in the multiple LED chips of the patterned LED substrate 2 is not limited to the above example.

[0094] Furthermore, the LED drive circuit 4 in Fig. 6 can control each LED chip, which may have a different basic light emission amount corresponding to the number of series as described above, as a variable light amount according to the light distribution pattern by PWM control. The LED drive circuit 4 in Fig. 6 is equipped with a step-down control circuit 129 and the like for this purpose. The step-down control circuit 129 of each LED drive circuit 4 generates a step-down voltage by stepping down the common power supply voltage according to the basic light emission amount (corresponding number of series) of each corresponding LED chip. The common power supply voltage is designed according to the LED chip with the maximum number of series. Step-down is not required for the LED chip with the maximum number of series.

[0095] Then, the LED drive circuit 4 controls ON / OFF of the switch 130 based on the step-down voltage and a drive control signal corresponding to the light distribution pattern, thereby generating a PWM LED drive current. With this LED drive current, the actual amount of emitted light relative to the basic amount of emitted light can be variably determined according to the ratio of the lengths of the PWM on period and off period.

[0096] With this configuration, for example, in the center of Figure 2, near LED chip 35 and LED chip 26, a high basic amount of emitted light is ensured, and depending on the light distribution pattern at that time, it is possible to reduce the amount of emitted light below the basic amount in each area divided by the shielding plate, for example to prevent glare.

[0097] [Lighting area] FIG. 8 shows an outline of the configuration of the lighting area according to the law. FIG. 8 shows the lighting area in the case of low beam for passing vehicles when driving on the right side. The lines hh indicate the horizontal line and horizontal plane. The lines vv indicate the vertical line and vertical plane corresponding to the optical axis of the headlight. In the case of driving on the left side, the lighting area is configured by inverting the left and right with respect to the line vv in this figure. In this low beam lighting area, zone II 802 and zone IV 804 are turned on (high luminance) and zone III 803 is turned off (low luminance), thereby preventing dazzling of oncoming vehicles. The diagonal line 805 of the boundary between zone II 802 and zone III 803 is called the cutoff line. For example, the luminance [cd] required at point BR in zone II 802 is set to a maximum of 1750 cd. The luminance required at point B50L in zone III 803 is set to a maximum of 350 cd. The luminance range, etc. are also specified for the requirements of high beam.

[0098] [Light distribution pattern] The following describes specific examples of patterns of beam distribution control associated with the modes in the headlight of embodiment 1. As described above, the arrangement (in other words, patterning) of the multiple LED chips and multiple shielding plates on the main surface of the patterned LED substrate 2 is designed with predetermined positions, shapes, and dimensions in accordance with the configuration of the illumination area in front of the vehicle.

[0099] [First pattern] Fig. 9 shows the configuration of the first pattern corresponding to the normal low beam driving mode as the light distribution pattern. In Fig. 9 and other figures, similar to Fig. 2, the configuration of the illumination area in front of the vehicle is superimposed as it is to make it easier to understand, and the configuration is shown as the main surface (XY surface) of the patterning LED substrate 2 is viewed from back to front in the Z direction. When the main surface of the patterning LED substrate 2 is viewed from front to back in the Z direction, the configuration of Fig. 9 and other figures can be considered as being reversed from left to right.

[0100] In the first pattern in FIG. 9, regions 901 and 902 indicated by dashed lines are both lighting regions where the LED chips are lit. The region 901 includes the LED chips 23 to 29 on the first line 2B except for the left and right ends, and the LED chips 32 and 33 on the second line 2C. The region 902 includes the LED chip 34 and the LED chip 31 on the second line 2C. The portion on the second line 2C from the central LED chip 35 to the right LED chip 42 is turned off. The region including the region 901 and the region 902 constitutes an illumination region corresponding to the low beam as shown in FIG. 8. In particular, the region 902 also has a cutoff line formed by the shielding plate 51.

[0101] [Second pattern] FIG. 10 shows the configuration of the second pattern corresponding to the normal high beam driving mode. In the second pattern, areas 1001 and 1002 are the lighting areas. Area 1001 includes LED chips 23-29 on the first line 2B excluding the left and right ends. Area 1002 includes LED chips 32-42 and LED chip 31 on the second line 2C. Areas 1001 and 1002 form an illumination area corresponding to high beam. Area 1002 on the upper side in the Y direction corresponds to the front of the vehicle's lane when driving, and requires high luminous intensity.

[0102] [Third pattern] FIG. 11 shows the configuration of the third pattern corresponding to the mode when driving with high beam and ADB. The third pattern is a light distribution pattern in which ADB light distribution control is applied to high beam. The headlight of the first embodiment is capable of selectively using not only a normal high beam (FIG. 10) that does not apply ADB, but also a high beam that applies ADB. The configuration of the LED chips and shielding plate of the patterned LED substrate 2 is designed to be compatible with the selective control of such a plurality of light distribution patterns.

[0103] The third pattern in FIG. 11 has an area 1100, areas 1101, 1102, and 1103. In the third pattern, the areas 1100, 1101, and 1102 are turned on areas, and the area 1103 is turned off area (illustrated by a dot pattern). The area 1100 is an area on the first line 2B similar to that described above. The areas 1101, 1102, and 1103 are an example of dividing an area including the LED chips 32 to 42 on the second line 2C into three areas. The area 1101 is an area including the LED chips 32 to 34, the LED chip 31, and the LED chips 35 to 37 from the left. The area 1102 is an area including the LED chips 38 and 39. The area 1103 is an area including the LED chips 40, 41, and 42. The areas 1101 and 1102 are divided by the shielding plate 54 in particular. The area 1102 and the area 1103 are particularly separated by the shielding plate 56 .

[0104] In terms of the illumination area, the area 1103 corresponds to the area in front of the vehicle on the right side of the lane in which the vehicle is traveling. In a situation where there is an oncoming vehicle (another vehicle) in this area, for example, one of the modes is to perform ADB light distribution control such that the area is not illuminated or is dimmed in order to prevent dazzling. The third pattern corresponds to such a mode.

[0105] As shown in the figure, the region on the second line 2C on the upper side in the Y direction has a configuration in which multiple LED chips are divided by multiple shielding plates, and therefore can be separated into, for example, three regions 1101, 1102, and 1103 in the third pattern by control. Then, by turning off or dimming the LED chips associated with a specified region, for example region 1102, a high beam with ADB applied can be achieved.

[0106] In the above third pattern, a certain area 1102 is set as an off area, but as can be easily understood from the drawing, it is similarly possible to realize an ADB with other contents by changing the target area and direction by treating the areas divided by the shielding plate as constituent units and setting the other constituted areas to off or dimming.

[0107] When each light distribution pattern is applied, if there is a variably controllable parameter in the pattern (for example, an area to be subjected to glare prevention by ADB), the parameter value may be specified together with the specification of the mode, etc. from the vehicle controller 102. Alternatively, the microcontroller 126 may automatically control the parameter value.

[0108] [Fourth pattern] FIG. 12 shows the configuration of the fourth pattern corresponding to the driving mode with high beam and variable light distribution width control. The fourth pattern is a light distribution pattern in which variable light distribution width control is applied to high beam. Variable light distribution width control here refers to variably controlling the width (horizontal, width in the X direction) of the area illuminated as high beam by using multiple areas divided by LED chips and shielding plates, for example, targeting the area on the upper second line 2C. The lower area 1200 is the same lighting area as described above.

[0109] In this example, the region on the upper second line 2C has five regions, 1201, 1202, 1203, 1204, and 1205 from the left. Region 1201 is a region that includes LED chips 32 and 33. Region 1202 is a region that includes LED chip 34. Region 1203 is a region that includes LED chips 31, 35, and 36. Region 1204 is a region that includes LED chips 37 and 38. Region 1205 is a region that includes LED chips 39 to 42.

[0110] In the variable light distribution width control in the fourth pattern, the width of the high beam area is determined, for example, according to the vehicle speed. For example, at low speeds, it is preferable that the width of the high beam area is wider, and at high speeds, it is preferable that the center (front) is brighter than the width of the high beam area. In the variable light distribution width control, the width of the high beam area may change on the time axis according to changes in vehicle speed.

[0111] For example, in a certain light distribution width variable control corresponding to low speed, all five regions from region 1201 to region 1205 are set as lighted regions. That is, the width of the high beam at this time is a width corresponding to the region on the second line 2C including region 1201 to region 1205. Also, at this time, for example, in region 1203 corresponding to the central part, the luminous intensity may be relatively smaller than that at other control times. Also, in another light distribution width variable control, for example, three regions from region 1202 to region 1204 are set as lighted regions, and region 1201 and region 1205 are set as extinguished regions. That is, the width of the high beam at this time is a width corresponding to the region from region 1202 to region 1204. Also, at this time, for example, in region 1203 corresponding to the central part, the luminous intensity may be relatively larger than that at other control times, for example, to the maximum.

[0112] [5th ​​pattern] FIG. 13 shows the configuration of a fifth pattern corresponding to a driving mode with high beam and variable light distribution center control. The fifth pattern is a light distribution pattern in which variable light distribution center control is applied to high beam. The variable light distribution center control here refers to variably controlling the area (also referred to as light distribution center area) that has the largest amount of light (corresponding luminous intensity) among the areas illuminated by light distribution control. In other words, this variable light distribution center control provides areas with relatively large and small amounts of light within the illumination area. In this example, the variable light distribution center control specifically includes the following two types of control.

[0113] The first light distribution center variable control controls a designated part of the high beam area (the area on the second line 2C) so that the light quantity is the highest at a certain point in time. For example, when a vehicle is traveling around a right curve, it is preferable for the high beam from the headlights to illuminate a direction / area to the right of the center. In response to this, this control basically lights up the area on the second line 2C during high beam, and also makes a designated part of that area have the highest light quantity. In other words, when the designated area is set to a first light quantity, the other area is set to a second light quantity that is smaller than the first light quantity. This makes it possible to realize a high beam that is suitable for traveling around a right curve.

[0114] In the example of FIG. 13, the region on the upper second line 2C has, for example, six regions, namely, from the left, regions 1301, 1302, 1303, 1304, 1305, and 1306. Region 1301 is a region that includes LED chips 32 and 33. Region 1302 is a region that includes LED chip 34. Region 1303 is a region that includes LED chips 31, 35, and 36. Region 1304 is a region that includes LED chips 37 and 38. Region 1305 is a region that includes LED chips 39 and 40. Region 1306 is a region that includes LED chips 41 and 42.

[0115] At a certain point in time, for example, in response to driving around a right curve, area 1301 is set as an off area, and other areas 1302 to 1306 are set as on areas. That is, in response to driving around a right curve, a high beam area is formed as an area to the right of the center. Furthermore, within the right area (five areas), a specified part of the area, for example, the central area 1304 (shown in a dashed line frame) of the five, is set as an on area with the highest light intensity. The amount of light emitted by the LED chip can be controlled by the aforementioned PWM control or the like. This allows for high beams that are suitable for driving around a right curve.

[0116] Furthermore, the second light distribution center variable control is added with control on the time axis. Although only the first control is sufficient, by adding the second control, a more suitable high beam can be realized. In this second control, the area in the high beam area where the light amount is the highest is moved on the time axis. For example, the area where the light amount is the highest is determined according to the vehicle speed. For example, when driving on a right curve at a low speed, it is preferable to make the area of ​​the upper high beam area where the light amount is the highest relatively closer to the right than when driving on a high speed curve. When driving on a right curve at a high speed, it is preferable to make the area of ​​the high beam area where the light amount is the highest closer to the center. In this way, in the second control, for example, when driving on a right curve, the area of ​​the high beam area where the light amount is the highest is moved left and right on the time axis according to the change in the vehicle speed.

[0117] As an example of the second control, when traveling at a low speed around a right curve, among the regions 1302 to 1306 to be turned on, for example, region 1306 or region 1305 is set to be the region with the greatest amount of light. When traveling at a high speed, among the regions 1302 to 1306 to be turned on, for example, region 1304 is set to be the region with the greatest amount of light.

[0118] [Sixth pattern] FIG. 14 shows the sixth pattern corresponding to the mode when cornering. Cornering means turning right or left. The sixth pattern is a light distribution pattern for cornering that is different from high beam and low beam. The sixth pattern is a light distribution pattern that, for example, illuminates an area near the right end of the lighting area with respect to the center when turning right, and illuminates an area near the left end of the lighting area with respect to the center when turning left. For example, if such lighting is used when turning right, it is possible to pay attention to the area to turn right.

[0119] In the sixth pattern, the first line 2B has areas 1401 and 1402, which are lighted areas. The area 1401 is an area near the left end of the area on the first line 2B, and the area 1402 is an area near the right end of the area on the first line 2B. The area 1401 includes the LED chip 22 on the left end, and is shielded by the shielding plates 43 and 44. The area 1402 includes the LED chip 30 on the right end, and is shielded by the shielding plates 45 and 46.

[0120] These shielding plates are formed to extend in an oblique direction as described above. For example, shielding plate 43 extends diagonally downward to the right from the upper left corner toward LED chip 23, and a gap is provided between shielding plate 43 and LED chip 23. There is an opening between the end of shielding plate 43 and the end of shielding plate 44. When LED chip 22 is turned on, it is shielded by shielding plates 43 and 44, and light emission spreads to the right from the opening, so that region 1401 has a shape that spreads to the vicinity of LED chip 23.

[0121] Conventional vehicles use cornering lamps separate from headlights when cornering. In contrast, the headlight of the first embodiment can provide illumination in the sixth pattern when cornering, and this headlight alone can provide a beam when cornering similar to that of a cornering lamp.

[0122] In addition, the sixth pattern uses a diagonal shielding plate as shown in the figure to form diagonal areas 1401, 1402 that spread outward to the left and right. The human eye has a general characteristic of having an eye-catching effect. Taking this into consideration, the diagonal areas 1401, 1402 as shown in the figure are designed. This makes it easier for people to recognize the beam when cornering.

[0123] [7th pattern] FIG. 15 shows a seventh pattern corresponding to a mode for improving white line recognition (in other words, emphasizing white line) in rainy weather, etc. The white lines here are the left and right white lines constituting the vehicle's lane on the road. In rainy weather, etc., the white lines may be difficult to see. The seventh pattern is a light distribution pattern that emphasizes the white lines so that they are easily recognized by human eyes, in addition to high beams and low beams. The seventh pattern has areas 1501 and 1502 on the first line 2B, which are set as lighted areas. The area 1501 includes the LED chip 25 one chip left from the center, and is an area that is shielded by the shielding plates 47 and 48. The area 1502 includes the LED chip 27 one chip right from the center, and is an area that is shielded by the shielding plates 49 and 50. The area 1501 is designed with a position, shape, size, etc. that correspond to the white line on the left side of the vehicle's lane. The area 1502 is designed with a position, shape, size, etc. that correspond to the white line on the right side of the vehicle's lane.

[0124] The shielding plates 47, 48 are formed to extend diagonally upward to the right from the bottom left toward the center on the second line 2C, and both ends are open. The shielding plates 49, 50 are formed to extend diagonally upward to the left from the bottom right toward the center on the second line 2C, and both ends are open. When the LED chip 25 is turned on, it is shielded by the shielding plates 47, 48, and light emission spreads from the open parts. As a result, the area 1501 is a diagonal band-shaped area corresponding to the white line on the left side.

[0125] If the seventh pattern is used during rainy weather, the white lines will be more noticeable, allowing for safer driving.

[0126] [Multiple Patterns] The above-mentioned patterns can be applied in combination. For example, when it is desired to apply high beam, ADB, and white line recognition depending on the vehicle driving situation and mode, the third pattern and the seventh pattern can be combined.

[0127] The headlight of the first embodiment has a common configuration so that multiple patterns such as those in the above example can be selected and executed. As the configuration, the multiple LED chips and multiple shielding plates of the patterned LED substrate 2, the LED drive circuit 4, etc. are designed.

[0128] The multiple patterns may correspond to multiple modes required by a certain vehicle manufacturer. In addition, if multiple vehicle manufacturers each have different modes required, multiple patterns may be provided corresponding to all the multiple modes required by the multiple vehicle manufacturers. In this case, one headlight can be used to accommodate multiple vehicle manufacturers.

[0129] [Projection lens] The projection lens of the first embodiment is a projection lens constituting the headlight of the first embodiment as described above, and is an optical element that is arranged in front of the patterning LED substrate 2, like the projection lens 1 in Fig. 1, and projects a suitable beam forward with a predetermined resolution based on forward light emission (emitted light) from the patterning LED substrate 2 to form an illumination area in front of the vehicle. In addition, this projection lens is not limited to vehicle headlights and the patterning LED substrate 2, and can be similarly applied to other illumination devices and light source devices.

[0130] [Headlight control method] The headlight control method of the first embodiment is a method for controlling the headlight of the first embodiment as described above, and in particular, a method for controlling the headlight with a light distribution pattern according to the mode of the vehicle to form a suitable illumination area in front of the vehicle. Based on the configuration of Fig. 6 etc., this headlight control method includes a step in which the LED drive circuit 4 (particularly the microcontroller 126) selects and determines a light distribution pattern according to vehicle information or mode designation, a step in which the LED PWM drive units are driven and controlled in accordance with the light distribution pattern, and a step in which the LED chips of the patterned LED substrate 2 are supplied with electric signals (LED drive currents) by PWM control from the LED PWM drive units to emit light while controlling the on / off and light emission amount of the LED chips.

[0131] [Effects, etc.] As described above, the headlight etc. of embodiment 1 differs from the conventional bi-function type or the type using an array / matrix type optical element in that it can be configured with a reduced number of mechanical parts and optical elements, thereby making it possible to realize a suitable headlight etc. that can reduce costs, improve reliability, and ensure the amount of light in the center of the illumination area.

[0132] Although the embodiments of the present disclosure have been specifically described above, they are not limited to the above-described embodiments and can be modified in various ways without departing from the scope of the present disclosure. In each embodiment, components can be added, deleted, or replaced, except for essential components. Unless otherwise specified, each component can be singular or plural.

[0133] The technology according to the present embodiment can provide a headlight device that can ensure the amount of light in the center of the lighting area when the vehicle is traveling, and can ensure forward visibility by the lighting area that is turned on, thereby contributing to supporting safe driving and preventing traffic accidents. This contributes to the achievement of the Sustainable Development Goals (SDGs) proposed by the United Nations, "Good Health and Well-Being." [Explanation of symbols]

[0134] 1...projection lens, 2...patterning LED substrate, 3...heat sink, 4...LED drive circuit, 21...phosphor, 22-42...LED chips, 43-58...shielding plate, 61...plate.

Claims

1. An LED substrate on which a plurality of LED chips are arranged; an LED driving circuit that drives the LED chips on the LED substrate; a projection lens disposed forward in a direction perpendicular to the LED board and configured to project light emitted from the LED board forward as a beam; Equipped with The LED substrate is Plate and The plurality of LED chips are disposed on the plate and emit light having wavelengths ranging from violet to blue; a phosphor disposed on the plate to cover the plurality of LED chips, the phosphor emitting yellow or red and green light using the purple to blue wavelength light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including a low beam and a high beam as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; Each LED chip of the plurality of LED chips has one or more LED devices connected in series in a predetermined number of series according to the determined position; The number of LED chips in series is larger in a central portion of the LED chips than in a peripheral portion of the LED chips in accordance with the configuration of the forward illumination region. Headlight.

2. 2. The headlight according to claim 1, the LED substrate has a shielding plate disposed between predetermined LED chips of the plurality of LED chips so as to stand forward, the shielding plate shielding light emitted from the LED chips and limiting forward dispersion from the LED chips; The shielding plate is disposed on the plate at a predetermined position and in a predetermined shape so as to realize the light distribution control of the plurality of patterns. Headlight.

3. 2. The headlight according to claim 1, The LED driving circuit includes: a step-down control circuit that generates step-down voltages corresponding to the respective LED chips from a common power supply voltage; and a switch for PWM-controlling each of the LED chips in accordance with the selected pattern. Headlight.

4. 3. The headlight according to claim 2, The shielding plate stands on the plate to the surface of the phosphor. Headlight.

5. 3. The headlight according to claim 2, The shielding plate stands on the plate at a position a predetermined distance below the surface of the phosphor. Headlight.

6. An LED substrate on which a plurality of LED chips are arranged; an LED driving circuit that drives the LED chips on the LED substrate; a projection lens disposed forward in a direction perpendicular to the LED board and configured to project light emitted from the LED board forward as a beam; Equipped with The LED substrate is Plate and The plurality of LED chips are disposed on the plate and emit light having wavelengths ranging from violet to blue; a phosphor disposed on the plate to cover the plurality of LED chips, the phosphor emitting yellow or red and green light using the purple to blue wavelength light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including a low beam and a high beam as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; The LED drive circuit stores setting information for drive control of the plurality of LED chips corresponding to the plurality of light distribution control patterns in a memory. Headlight.

7. An LED substrate on which a plurality of LED chips are arranged; an LED driving circuit that drives the LED chips on the LED substrate; a projection lens disposed forward in a direction perpendicular to the LED board and configured to project light emitted from the LED board forward as a beam; Equipped with The LED substrate is Plate and The plurality of LED chips are disposed on the plate and emit light having wavelengths ranging from violet to blue; a phosphor disposed on the plate to cover the plurality of LED chips, the phosphor emitting yellow or red and green light using the purple to blue wavelength light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including a low beam and a high beam as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; the LED substrate has a shielding plate disposed between predetermined LED chips of the plurality of LED chips so as to stand forward, the shielding plate shielding light emitted from the LED chips and limiting forward dispersion from the LED chips; the shielding plate is disposed on the plate at a predetermined position and in a predetermined shape so as to realize the light distribution control of the plurality of patterns; The configuration of the forward illumination area includes white line areas on the left and right of the vehicle's lane, the plurality of LED chips include LED chips arranged at positions corresponding to the white line areas, One of the patterns is a pattern that brightens the area of ​​the white line, The shielding plate includes a shielding plate disposed at a position determined to divide the white line area, the shielding plate being disposed in an oblique direction within a main surface of the LED substrate. Headlight.

8. 3. The headlight according to claim 2, the plurality of LED chips include LED chips arranged at positions corresponding to the low beam area in the forward illumination area, The shielding plate is arranged at a position determined to divide the low beam region, and includes a shielding plate arranged in an oblique direction within the main surface of the LED substrate in correspondence with the cutoff line, Headlight.

9. 3. The headlight according to claim 2, the plurality of LED chips include LED chips arranged at positions corresponding to the high beam area in the forward illumination area, The shielding plate includes a shielding plate disposed at a predetermined position for further dividing the high beam region into a plurality of regions, As one of the patterns, a pattern for controlling light distribution of the high beam and ADB is included, The LED drive circuit drives and controls the high beam so that a part of the high beam area is turned off or dimmed when the high beam is in a high beam and ADB light distribution control pattern is in effect. Headlight.

10. An LED substrate on which a plurality of LED chips are arranged; an LED driving circuit that drives the LED chips on the LED substrate; a projection lens disposed forward in a direction perpendicular to the LED board and configured to project light emitted from the LED board forward as a beam; Equipped with The LED substrate is Plate and The plurality of LED chips are disposed on the plate and emit light having wavelengths ranging from violet to blue; a phosphor disposed on the plate to cover the plurality of LED chips, the phosphor emitting yellow or red and green light using the purple to blue wavelength light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including a low beam and a high beam as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; the LED substrate has a shielding plate disposed between predetermined LED chips of the plurality of LED chips so as to stand forward, the shielding plate shielding light emitted from the LED chips and limiting forward dispersion from the LED chips; the shielding plate is disposed on the plate at a predetermined position and in a predetermined shape so as to realize the light distribution control of the plurality of patterns; The configuration of the forward lighting area includes a cornering lighting area, the plurality of LED chips include LED chips arranged at positions corresponding to an area of ​​illumination during cornering, The shielding plate includes a shielding plate disposed at a position determined to divide an illumination area during cornering, the shielding plate being disposed in an oblique direction within a main surface of the LED substrate, One of the patterns includes a pattern for controlling light distribution during cornering, The LED drive circuit controls driving so as to brighten the lighting area when the cornering is performed in a pattern in which light distribution control is performed when the cornering is performed. Headlight.

11. An LED substrate on which a plurality of LED chips are arranged; an LED driving circuit that drives the LED chips on the LED substrate; a projection lens disposed forward in a direction perpendicular to the LED board and configured to project light emitted from the LED board forward as a beam; Equipped with The LED substrate is Plate and The plurality of LED chips are disposed on the plate and emit light having wavelengths ranging from violet to blue; a phosphor disposed on the plate to cover the plurality of LED chips, the phosphor emitting yellow or red and green light using the purple to blue wavelength light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including a low beam and a high beam as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; the LED substrate has a shielding plate disposed between predetermined LED chips of the plurality of LED chips so as to stand forward, the shielding plate shielding light emitted from the LED chips and limiting forward dispersion from the LED chips; the shielding plate is disposed on the plate at a predetermined position and in a predetermined shape so as to realize the light distribution control of the plurality of patterns; the plurality of LED chips include a plurality of LED chips arranged at positions corresponding to the high beam region in the forward illumination region, The shielding plate includes a shielding plate disposed at a predetermined position for further dividing the high beam region into a plurality of regions, As one of the patterns, a pattern in which the high beam is used and the light distribution width is variable and controlled is included, The LED drive circuit controls the high beam to change the light distribution width of the high beam area by turning on a selected part of the high beam area and turning off or dimming another selected part of the high beam area when the high beam is in a high beam and light distribution width variable control pattern. Headlight.

12. An LED substrate on which a plurality of LED chips are arranged; an LED driving circuit that drives the LED chips on the LED substrate; a projection lens disposed forward in a direction perpendicular to the LED board and configured to project light emitted from the LED board forward as a beam; Equipped with The LED substrate is Plate and The plurality of LED chips are disposed on the plate and emit light having wavelengths ranging from violet to blue; a phosphor disposed on the plate to cover the plurality of LED chips, the phosphor emitting yellow or red and green light using the purple to blue wavelength light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including a low beam and a high beam as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; the LED substrate has a shielding plate disposed between predetermined LED chips of the plurality of LED chips so as to stand forward, the shielding plate shielding light emitted from the LED chips and limiting forward dispersion from the LED chips; the shielding plate is disposed on the plate at a predetermined position and in a predetermined shape so as to realize the light distribution control of the plurality of patterns; the plurality of LED chips include a plurality of LED chips arranged at positions corresponding to the high beam region in the forward illumination region, The shielding plate includes a shielding plate disposed at a predetermined position for further dividing the high beam region into a plurality of regions, As one of the patterns, a pattern in which the high beam is used and the light distribution center is variable and controlled is included, When the high beam is in a pattern in which the light distribution center is variable, the LED drive circuit controls the light distribution center of the high beam area to be changed by turning on a selected part of the high beam area and turning off or dimming another selected part of the high beam area. Headlight.

13. A projection lens constituting an illumination device, The illumination device includes an LED board on which a plurality of LED chips are arranged, an LED drive circuit that drives the plurality of LED chips on the LED board, and the projection lens that is arranged forward in a direction perpendicular to the LED board and projects light emitted from the LED board forward as a beam, the LED substrate includes a plate, the plurality of LED chips arranged on the plate and emitting blue light, and a phosphor arranged on the plate to cover the plurality of LED chips and emitting yellow light using the blue light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control pattern selected from a plurality of light distribution control patterns as a light distribution control of a beam forward; The LED drive circuit controls the on / off and light amount of each LED chip on the LED board, thereby realizing the light distribution control of the selected pattern; The projection lens corrects the light emitted from the LED board for aberration and projects the light forward as a beam. Projection lens.

14. 14. The projection lens according to claim 13, the projection lens includes a convex lens having an aspheric shape on an entrance surface and an exit surface, and a concave lens having an aspheric shape on an entrance surface and an exit surface, the concave lens being disposed on the exit side of the convex lens. Projection lens.

15. A headlight control method for controlling a headlight, comprising: The headlight includes an LED board on which a plurality of LED chips are arranged, an LED drive circuit that drives the plurality of LED chips on the LED board, and a projection lens that is arranged forward in a direction perpendicular to the LED board and projects light emitted from the LED board forward as a beam, the LED substrate includes a plate, the plurality of LED chips arranged on the plate and emitting blue light, and a phosphor arranged on the plate to cover the plurality of LED chips and emitting yellow light using the blue light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including at least a low beam, a high beam, and an adaptive driving beam (ADB) as a light distribution control of a beam forward; Each LED chip of the plurality of LED chips has one or more LED devices connected in series in a predetermined number of series according to the determined position; The number of LED chips in series is larger in a center portion of the LED chips than in a peripheral portion of the LED chips in the center portion of the LED chips in the front illumination region. The headlight control method includes: The LED driving circuit selects the pattern corresponding to a lighting mode based on an instruction or vehicle information input according to a vehicle driving situation; and a step of controlling, by the LED drive circuit, turning on and off and controlling the amount of light of each of the plurality of LED chips on the LED substrate for light distribution control of the selected pattern. Headlight control method.

16. A headlight control method for controlling a headlight, comprising: The headlight includes an LED board on which a plurality of LED chips are arranged, an LED drive circuit that drives the plurality of LED chips on the LED board, and a projection lens that is arranged forward in a direction perpendicular to the LED board and projects light emitted from the LED board forward as a beam, the LED substrate includes a plate, the plurality of LED chips arranged on the plate and emitting blue light, and a phosphor arranged on the plate to cover the plurality of LED chips and emitting yellow light using the blue light as an excitation light source; each of the plurality of LED chips on the plate is disposed at a predetermined position corresponding to a configuration of a forward illumination area so as to realize a light distribution control of a pattern selected from a plurality of light distribution control patterns including at least a low beam, a high beam, and an adaptive driving beam (ADB) as a light distribution control of a beam forward; the LED drive circuit stores, in a memory, setting information for drive control of the plurality of LED chips corresponding to the plurality of light distribution control patterns; The headlight control method includes: The LED driving circuit selects the pattern corresponding to a lighting mode based on an instruction or vehicle information input according to a vehicle driving situation; and a step of controlling, by the LED drive circuit, turning on and off and controlling the amount of light of each of the plurality of LED chips on the LED substrate for light distribution control of the selected pattern. Headlight control method.

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