阅读说明：本技术 车辆用灯具 (Vehicle lamp ) 是由 村上一臣 内田直树 于 2020-01-28 设计创作，主要内容包括：车辆用灯具具有：激光光源,其生成椭圆点光；光学系统,其将所述椭圆点光变为纵横比1：1的点光；以及扫描机构,其将纵横比1：1的所述点光朝向车辆的外部扫描,由此描绘显示出配光图案。(The vehicle lamp includes: a laser light source that generates an elliptical spot light; an optical system that converts the elliptical spot light into a light having an aspect ratio of 1: 1, spot light; and a scanning mechanism that changes the aspect ratio 1: 1 toward the outside of the vehicle, thereby depicting and displaying a light distribution pattern.)

1. A lamp for a vehicle, comprising:

a laser light source that generates an elliptical spot light;

an optical system that converts the elliptical spot light into a light having an aspect ratio of 1: 1, spot light; and

a scanning mechanism which converts an aspect ratio of 1: 1 toward the outside of the vehicle, thereby depicting and displaying a light distribution pattern.

2. The vehicular lamp according to claim 1, wherein,

the optical system is an anamorphic lens.

3. The vehicular lamp according to claim 1, wherein,

the optical system is a pair of cylindrical lenses,

one cylindrical lens is arranged in series on the central axis with respect to the other cylindrical lens in a state of being rotated by 90 ° around the central axis.

4. The vehicular lamp according to claim 1, wherein,

the optical system is a special lens and the optical system is,

a microlens array is formed on the light incident surface of the special lens, and the exit surface of the special lens is an aspherical surface.

5. The vehicular lamp according to any one of claims 1 to 4,

the vehicle lamp is a light distribution variable type headlamp.

Technical Field

The present invention relates to a vehicle lamp that scans a laser spot light in a two-dimensional direction in front of a vehicle to draw and display a light distribution pattern.

Background

Patent document 1 discloses a vehicle lamp that displays a headlamp having a predetermined shape. As shown in paragraph [0136] [0166] [0353] of patent document 1 and fig. 62, etc., an elliptical laser spot light is scanned in the horizontal direction by a high-speed oscillating mirror to draw a horizontal line of light, and the horizontal scanning by the elliptical laser spot light is repeatedly drawn while being shifted little by little in the vertical direction, whereby the drawn horizontal lines are stacked up and down to form a headlamp display of a predetermined shape. The vehicle lamp of patent document 1 can perform a light distribution variable type headlamp display, that is, a headlamp display in a shape deviating from an irradiation range by turning off an elliptical laser spot light when scanning an object, so as not to dazzle a driver's seat, a pedestrian, and the like of an oncoming vehicle.

Spot light formed by high-output laser light used in scanning is generally generated in an elliptical shape. In the laser spot light, the outer periphery of the elliptical spot light is displayed darkest and blurred near both ends of the major axis because the laser spot light extends in an elliptical shape from the center and the resolution is reduced or fluctuates toward both ends of the major axis. In the vehicle lamp of patent document 1, as shown in fig. 62, the irradiated laser spot light is extended in an elliptical shape with a decrease and fluctuation in resolution, and thus a part of the oblong elliptical spot light is often scanned in a repeated state in a direction (longitudinal direction) orthogonal to the scanning direction (lateral direction).

Patent document 1: japanese patent laid-open publication No. 2016-207483

Disclosure of Invention

The elliptical spot light shown in patent document 1 is repeated in the vertical direction orthogonal to the scanning direction when the scanning direction is set to the horizontal direction during scanning. Therefore, when turning off the elliptical spot lights of a certain row and attempting to avoid the irradiation of the unnecessary irradiation object (the driver of the oncoming vehicle, the pedestrian, or the like), the vehicle lamp needs not only to turn off the elliptical spot lights of the row but also to turn off the elliptical spot lights above and below the row that do not need the irradiation object to repeatedly irradiate light. As a result, although it is not necessary to turn off the lamp, the area in which the lamp is turned off is enlarged beyond necessity, and the irradiation range for drawing a light distribution pattern or the like is narrowed.

Specifically, the light distribution variable type headlamp of fig. 62 of patent document 1 is formed by 4 rows of horizontal lines that overlap vertically. When scanning the 2 nd and 3 rd rows from above, the vehicle lamp turns off the elliptical spot light when scanning the portion where the driver seat is located, thereby avoiding the irradiation to the driver seat. However, if the driver's seat is high or low, the vehicle lamp must be turned off in the 1 st row or the 4 th row even when the driver's seat is in the scanning range of the 1 st row or the 4 th row. In this case, the formed light distribution pattern is insufficient to further eliminate the irradiation to the obliquely upper and lower sides of the vehicle in order to avoid the irradiation to the driver's seat.

In view of the above, the present invention provides a vehicle lamp that performs a drawing display of a light distribution pattern in which the freedom of an irradiation range is improved by preventing unnecessary turn-off of spot light during drawing scanning.

(1) The vehicle lamp of the invention comprises: a laser light source that generates an elliptical spot light; an optical system that converts the elliptical spot light into a light having an aspect ratio of 1: 1, spot light; and a scanning mechanism that changes the aspect ratio 1: 1 toward the outside of the vehicle, thereby depicting and displaying a light distribution pattern.

The (action) optical system generates a light beam having an aspect ratio of 1: 1, the resolution of the spot light in the direction orthogonal to the scanning direction in which a plurality of straight lines are generated up and down by repeated high-speed scanning by the spot light is improved.

(2) The optical system in the vehicular lamp is preferably an anamorphic lens.

(3) Preferably, the optical system in the vehicle lamp is a pair of cylindrical lenses, and one of the cylindrical lenses is arranged in series on a central axis of the other cylindrical lens while being rotated by 90 ° around the central axis.

(4) Preferably, the optical system in the vehicle lamp is a special lens, a microlens array is formed on a light incident surface of the special lens, and an exit surface of the special lens has an aspherical shape.

(5) The vehicle lamp is preferably a light distribution variable type headlamp.

A vehicle lamp as a light distribution variable headlamp performs a lighting operation by adjusting the aspect ratio of 1: 1, drawing and displaying a light distribution pattern after avoiding unnecessary irradiation objects (such as a driver's seat and a pedestrian of an oncoming vehicle) at a minimum necessary outside the vehicle.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the vehicle lamp, the fluctuation in the resolution of the spot laser light is reduced by increasing the resolution of the spot laser light, and the spot light to be scanned does not overlap in the direction orthogonal to the scanning direction. As a result, the scanning range in which lighting must be turned off when scanning the non-irradiation object becomes narrow, and the vehicle lamp can perform drawing and display of the light distribution pattern with enhanced freedom of the irradiation range ((effects of (1) to (4)).

According to the vehicle lamp, since the lamp is a light distribution variable headlamp, it is possible to exhibit the effect of the variable light distribution pattern ((5)) which irradiates the maximum range in which the unnecessary irradiation target (the driver's seat of the oncoming vehicle, the pedestrian, or the like) is avoided at the minimum necessary.

Drawings

Fig. 1A is a horizontal sectional view relating to embodiment 1 of the vehicular lamp.

Fig. 1B is an enlarged horizontal sectional view of the anamorphic lens of embodiment 1.

FIG. 1C is an enlarged vertical cross-sectional view of an anamorphic lens.

Fig. 2 is an oblique view of the scanning mechanism and the anamorphic lens related to embodiment 1, as viewed from obliquely front of the mirror.

Fig. 3 is an explanatory view of an optical path in the vehicular lamp related to embodiment 1.

Fig. 4A is a scanning explanatory diagram relating to an elliptical laser spot light in a conventional vehicle lamp.

Fig. 4B is a scanning explanatory diagram relating to the elliptical laser spot light in the vehicle lamp of the present invention.

Fig. 5 is an oblique view of the scanning mechanism and a plurality of cylindrical lenses related to embodiment 2 of the vehicle lamp as viewed from obliquely front of the reflector.

Fig. 6 is a partially enlarged horizontal cross-sectional view showing a condenser lens according to embodiment 3 of the vehicle lamp.

Detailed Description

Next, a preferred embodiment of the present invention will be described with reference to fig. 1A to 6. In the drawings, the direction of a road viewed from a driver of a vehicle (not shown) equipped with a vehicle lamp, which is a light distribution variable headlamp, is described as (upper: lower: left: right: front: rear: Up: Lo: Le: Ri: Fr: Re).

A vehicle lamp 1 according to embodiment 1 will be described with reference to fig. 1A to 1C. As shown in fig. 1A, a vehicle lamp 1 according to embodiment 1 includes a lamp body 2, a front surface cover 3, and a headlamp unit 4. The lamp body 2 has an opening portion on the front side of the vehicle, the front cover 3 is formed of a translucent resin, glass, or the like, and is attached to the opening portion of the lamp body 2 to form a lamp chamber S inside. The headlamp unit 4 shown in fig. 1A is disposed inside the lamp chamber S via a metal support member 5.

The headlamp unit 4 includes a projection lens 6, a phosphor 7, a laser light source 8, a scanning mechanism 9, and an anamorphic lens 10 as an optical system, which are shown in fig. 1A. The projection lens 6, the fluorescent body 7, the laser light source 8, the scanning mechanism 9, and the anamorphic lens 10 are all attached to the support member 5.

The support member 5 of fig. 1A has: a bottom plate portion 5 a; side plate sections (5b, 5c) that are integrated with the left and right end sections of the bottom plate section 5a, respectively; a lens support part 5d integrated with the front ends of the side plate parts (5b, 5 c); and a base plate portion 5e integrated with the base ends of the side plate portions (5b, 5 c). The lens support portion 5d has: a cylindrical portion 5d1 holding the projection lens 6 inside; and a flange portion 5d2 that is integrated with both the cylindrical portion 5d1 and the side plate portions (5b, 5 c). The base plate portion 5e includes screw fixing portions 5f and heat radiating portions 5g having a depth greater than the screw fixing portions 5 f.

The projection lens 6 in fig. 1A is a transparent or translucent plano-convex lens, and is fixed to the inside of the distal end portion of the cylindrical portion 5d1 of the lens support portion 5d in a state where the convex light exit surface 6a is directed forward. The fluorescent material 7 is plate-shaped and fixed to the inside of the base end portion of the cylindrical portion 5d1 of the lens support portion 5d behind the projection lens 6.

The laser light source 8 in fig. 1A has a blue or violet laser diode, and is fixed to a light source support portion 5h provided in the left side plate portion 5b of the support member 5 to dissipate heat during lighting. The phosphor 7 is formed as a yellow phosphor when the laser light source 8 is blue, and is formed as a yellow and blue phosphor when the laser light source 8 is purple, and emits white light. White light may be emitted by mixing red, blue, and green RGB lasers. The laser light source 8, which is a laser diode light source, generates a vertically long elliptical spot light. In the present embodiment, as shown in fig. 1B, the laser light source 8 is arranged to emit elliptical light that is vertically long. The scanning mechanism 9 shown in fig. 2 is a scanning device having a mirror 11 capable of tilting movement in the 2-axis direction, and is fixed to the front surface of the heat radiating portion 5 g.

The anamorphic lens 10 shown in fig. 1A to 1C is an optical system having a plano-convex lens whose curvature in a horizontal section is different from that of a light exit surface in a vertical section. Specifically, as shown in fig. 1B and 1C, the anamorphic lens 10 is formed to have a shape in which the curvature of the vertical section is larger than the curvature of the horizontal section. The anamorphic lens 10 is fixed to either the bottom plate portion 5a or the base plate portion 5e in a state of being disposed between the laser light source 8 and the reflection surface 11a of the reflector 11. The headlamp unit 4 is supported so as to be capable of tilting relative to the lamp body 2 by screwing 3 alignment screws 12 (1 of them is not shown) rotatably held by the lamp body 2 to the screw fixing portions 5f of the support member 5.

As shown in fig. 1B, 1C, and 2, the outgoing light B1 emitted from the laser light source 8 enters the anamorphic lens 10 from the incident surface 10a as elliptical laser spot light vertically elongated in the vertical direction, and has an aspect ratio of 1: 1 is emitted from the emission surface 10 b. The longitudinal elliptical laser spot light LS1, which causes a decrease in resolution near both ends of the major axis, is transmitted through the anamorphic lens 10 and has an aspect ratio of 1: 1 LS2, whereby the resolution in the vertical direction, which is reduced before the transmission of the anamorphic lens 10, is improved.

The laser spot light LS2 shown in fig. 1B and 1C passes through the anamorphic lens 10 so as to have an aspect ratio of 1: the mode 1 is focused on the reflection surface 11a of the mirror 11 and reflected. The scanning mechanism 9 shown in fig. 1A and 2 includes a mirror 11, a base 13, a rotating body 14, a pair of 1 st torsion bars 15, a pair of 2 nd torsion bars 16, a pair of permanent magnets 17, a pair of permanent magnets 18, and a terminal portion 19.

The plate-like rolling element 14 shown in fig. 2 is supported on the base 13 in a state of being tiltable in the right and left directions by the pair of 1 st torsion bars 15. The mirror 11 is supported by the rolling member 14 in a vertically rotatable state by a pair of 2 nd torsion bars 16. The pair of permanent magnets 17 and the pair of permanent magnets 18 are provided in the base 13 in the direction in which the pair of 1 st and 2 nd torsion bars (15, 16) extend, and the 1 st and 2 nd coils (not shown) that are independently controlled by a control mechanism (not shown) and are energized via the terminal portion 19 are provided in the mirror 11 and the rolling body 14, respectively.

The rolling element 14 shown in fig. 2 is tilted back and forth in the left-right direction about the axis of the 1 st torsion bar 15 based on the on/off of the current to the 1 st coil (not shown). The mirror 11 is tilted up and down reciprocally about the axis of the 2 nd torsion bar 16 based on the on/off of the current to the 2 nd coil (not shown). As shown in fig. 3, aspect ratio 1 reflected by the reflection surface 11 a: the laser spot light LS2 of fig. 1 is passed through or passed through the phosphor 7, the projection lens 6, the front end opening 20a of the extension mirror 20 in the lamp chamber S, and the front surface cover 3 in this order as shown in fig. 1A, and scanned in the vertical direction and the horizontal direction based on the tilting movement of the rotating body 14 and the tilting movement of the reflecting surface 11A in the vertical direction.

The scanning mechanism 9 shifts the mirror 11 in the vertical direction by a small distance in a small amount, and changes the white color to a value having an aspect ratio of 1: the laser spot light LS2 of 1 oscillates back and forth at high speed in the left-right direction. The scanning mechanism 9 displays a white light distribution pattern (head light display) having a predetermined shape by a scanning method in front of the outside of the vehicle by vertically stacking points and lines drawn at predetermined positions and with a predetermined length based on the on/off control of the laser light source 8. In other words, by dividing the aspect ratio 1: the laser spot light LS2 of 1 is scanned toward the outside of the vehicle, and a light distribution pattern is drawn and displayed. In addition, the scanning mechanism 9 may be a variety of scanning mechanisms such as an electrically controlled mirror and a rotating mirror, in addition to the MEMS mirror.

Next, a variable light distribution pattern (see fig. 4A) generated by a conventional vehicle lamp that scans an elliptical laser spot light and a variable light distribution pattern obtained by setting an aspect ratio of 1: advantages of the vehicle lamp 1 according to the present embodiment over conventional examples will be described by comparing the variable light distribution patterns (see fig. 4B) generated by the vehicle lamp 1 according to the present embodiment, which are scanned with the laser spot light LS2 of 1.

Reference numeral Pt1 in fig. 4A shows an elliptical laser spot light of a conventional vehicle lamp that is vertically long, and reference numeral LS2 in fig. 4B shows an aspect ratio 1: 1 laser spot light. Reference symbol Ld in fig. 4A and 4B indicates a road ahead of a vehicle (not shown), and reference symbol Hm indicates a pedestrian on the road ahead. Reference numeral Sc1 denotes a rectangular scanning region in front of the vehicle relating to the laser spot light, and numerals 1, 2, 3, 4 · n listed on the left side of the scanning region Sc1 indicate the number of steps of scanning by the laser spot light.

In the rectangular scanning region (reference numeral Sc1) shown in fig. 4B, the scanning mechanism 9 of the present embodiment is moved by the aspect ratio 1: the laser spot light LS2 of 1 scans the 1 st segment at high speed from the left end to the right end. Then, the scanning mechanism 9 tilts the mirror 11 obliquely downward to the left in a state where the laser spot light LS2 is turned off, and scans the left end of the 2 nd segment again to the right end at high speed, and repeats the scanning until the 3 and 4 · n segments. At this time, the scanning mechanism 9 scans the laser spot light LS2 so that the laser spot light LS2 of the upper and lower stages are adjacent to each other and do not overlap each other as shown in fig. 4B.

The scanning mechanism (not shown) of the conventional vehicle lamp shown in fig. 4A has a common point in that, similarly to the scanning mechanism 9 of the present embodiment, scanning from the left end to the right end by the elliptical laser spot light, tilting movement of the mirror obliquely downward to the left in a state where the spot light is turned off, and scanning from the left end to the right end in a segment below one segment are repeated at high speed up to n segments. However, the scanning by the conventional vehicle lamp is different from the scanning in the present embodiment shown in fig. 4B in that the scanning is performed so that the upper end and the lower end of the vertically adjacent elliptical laser spot light Pt1 overlap each other.

In the scanning by the conventional vehicle lamp shown in fig. 4A, since the spot light of the laser beam has a property of being condensed into an elliptical shape, a decrease and fluctuation in resolution occur at upper and lower ends of the spot light, and the spot light extends in an elliptical shape in the upper and lower sides. Therefore, in the scanning by the conventional vehicle lamp, even if the scanning is attempted to be performed so that the upper and lower end portions are adjacent to each other, the upper and lower end portions may unexpectedly overlap each other due to fluctuation in the decrease in resolution that occurs in the elliptical laser spot light.

According to the scanning by the vehicle lamp 1 of the present embodiment shown in fig. 4B, the aspect ratio of the elliptical laser spot light LS1 is set to 1: 1, the aspect ratio of the laser spot light LS2 is 1, i.e., the anamorphic lens 10: the laser spot light LS2 of 1 is free from blurring due to a decrease in resolution at the upper and lower ends. Therefore, it is not necessary to perform scanning by overlapping the upper and lower end portions as in the conventional case, and the upper and lower end portions of the laser spot light LS2 do not overlap each other unexpectedly due to fluctuation in the decrease in resolution.

As a result, in the present embodiment and embodiments 2 and 3 described later, the aspect ratio 1: 1, the light distribution variable type headlamp has the following advantages. For example, as shown in fig. 4B, the pedestrian Hm is in the range of the number Ar22 of the 2 nd paragraph. In order not to dazzle the pedestrian Hm when scanning the laser spot light, the vehicle lamp of the present embodiment is only required to have an aspect ratio of 1: the laser spot light LS2 of 1 may be turned off when the range of the reference symbol Ar22 is scanned in the 2 nd scan.

When the conventional vehicle lamp is used as the light distribution variable headlamp, as shown in fig. 4A, the pedestrian Hm is located in the range of reference sign Ar12 in the 2 nd stage. The upper and lower end portions of the elliptical laser spot light Pt1 overlap each other, whereby the light is irradiated to the face of the pedestrian Hm in 2 regions of numerals Ar11 and Ar 12. Therefore, in the case where the pedestrian Hm is not dazzled by the scanning, the conventional vehicle lamp needs to be turned off when the ranges of both the reference numerals Ar11 and Ar22 are scanned in the 1 st and 2 nd scans, and therefore, there is a problem in that the turn-off range when the light distribution is variable is enlarged beyond necessity. The aspect ratio 1: the laser spot light LS2 of 1 performs scanning without overlapping spot lights, and can minimize the light-off range.

Next, a vehicle lamp according to embodiment 2 of the present invention will be described with reference to fig. 5. In the vehicle lamp according to embodiment 2, the elliptical laser spot light LS1 has an aspect ratio of 1: the optical system of the laser spot light LS2 of embodiment 1 is different from that of the anamorphic lens 10 of embodiment 1. The vehicle lamp in embodiment 2 has a configuration common to that of embodiment 1, and therefore, illustration and description of the components other than the laser light source 8, the scanning mechanism 9, and the optical system are omitted.

In the vehicle lamp according to embodiment 2, the elliptical laser spot light LS1 is changed to have an aspect ratio of 1: the optical system of the laser spot light LS2 of fig. 1 includes a pair of cylindrical lenses 21 and 22 (see fig. 5) having the same shape, instead of the anamorphic lens 10. Each of the cylindrical lenses 21 and 22 has a shape in which a light exit surface of a transparent or translucent rectangular parallelepiped is formed as an arc surface. The cylindrical lenses 22 are arranged in series on the central axis L1 in a state rotated by 90 ° about the central axis L1 common to the cylindrical lenses 21.

The cylindrical lenses 21 and 22 shown in fig. 5 are disposed between the laser light source 8 and the scanning mechanism 9 in a state in which the light incident surfaces 21a and 22a face the laser light source 8 side and the light emitting surfaces 21b and 22b face the reflection surface 11a of the scanning mechanism 9. The outgoing light B1 emitted from the laser light source 8 sequentially passes through the cylindrical lenses 21 and 22 as the vertically long elliptical laser spot light LS1, and becomes 1: the circular laser spot light LS2 of 1 is incident on the reflection surface 11a of the scanning mechanism 9 and is reflected toward the front of the vehicle. Aspect ratio 1: the laser spot light LS2 of 1 is scanned forward of the vehicle with the reduced vertical resolution increased, and a variable light distribution pattern having a predetermined shape is displayed.

Next, a vehicle lamp according to embodiment 3 of the present invention will be described with reference to fig. 6. In the vehicle lamp according to embodiment 3, the elliptical laser spot light LS1 has an aspect ratio of 1: the optical system of the laser spot light LS2 of embodiment 1 is different from that of the anamorphic lens 10 of embodiment 1. The vehicle lamp in embodiment 3 has a configuration common to that of embodiment 1, and therefore, illustration and description of the components other than the laser light source 8 and the optical system are omitted.

In the vehicle lamp according to embodiment 3, the elliptical laser spot light LS1 is set to have an aspect ratio of 1: the optical system of the laser spot light LS2 of 1 includes a special lens 23, and the special lens 23 includes a microlens array 23a formed on a light incident surface and an aspheric light emitting surface 23 b.

The outgoing light B1 emitted from the laser light source 8 is transmitted from the microlens array 23a as elliptical laser spot light LS1 that is vertically long, passes through the special lens 23, and is emitted from the aspheric light emitting surface 23B, and thereby becomes 1: the circular laser spot light LS2 of 1 enters the reflection surface of the scanning mechanism and is reflected forward of the vehicle. Aspect ratio 1: the laser spot light LS2 of 1 is scanned forward of the vehicle with the reduced vertical resolution increased, and a variable light distribution pattern having a predetermined shape is displayed.

The present application claims priority based on japanese application No. 2019-034446 filed on 27/2/2019, which is incorporated by reference in its entirety.