CN210801011U

CN210801011U - Light irradiation device

Info

Publication number: CN210801011U
Application number: CN201921588682.7U
Authority: CN
Inventors: 北泽达磨; 向岛健太
Original assignee: Koito Manufacturing Co Ltd
Current assignee: Koito Manufacturing Co Ltd
Priority date: 2018-09-25
Filing date: 2019-09-23
Publication date: 2020-06-19
Anticipated expiration: 2029-09-23

Abstract

The utility model provides a can make some of grading pattern than the light irradiation device that other parts are bright. The light irradiation device (130) is provided with a light source (32) and a rotatable mirror (134) for reflecting light emitted from the light source (32), and the light irradiation device divides the light into a plurality of segments and scans linearly by displacing the reflection direction of the light by the rotation of the mirror (134). The lines include a first line and a second line. The mirror (134) has a first reflection surface (134a) for forming a first line and a second reflection surface (134b) juxtaposed with the first reflection surface (134a) in the direction of rotation of the mirror (134) for forming a second line, and the length of the first reflection surface (134a) in the direction of rotation is different from the length of the second reflection surface (134b) in the direction of rotation.

Description

Light irradiation device

Technical Field

The utility model relates to a light irradiation device.

Background

In recent years, there has been proposed a device that reflects light emitted from a light source toward the front of a vehicle and scans an area in front of the vehicle with the reflected light to form a predetermined light distribution pattern. For example, an optical unit including a plurality of light sources including light emitting elements and a rotating reflector of a blade scanning (registered trademark) type that reflects light emitted from the plurality of light sources on a reflecting surface while rotating in one direction around a rotation axis to form a desired light distribution pattern is known (see patent document 1). In the optical unit, the plurality of light sources are arranged such that light emitted from each light source is reflected at different positions on the reflecting surface of the rotating reflector.

Patent document 1: japanese laid-open patent publication No. 2015-26628

In addition, an optical unit using a polygon mirror instead of a rotating reflector is also known. In such an optical unit, there is room for improvement in the control of the light distribution pattern.

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

Therefore, an object of the present invention is to provide a light irradiation device capable of making a part of a light distribution pattern brighter than other parts.

Means for solving the problems

In order to solve the above problems, a light irradiation device of the present invention includes a light source and a rotatable mirror for reflecting light emitted from the light source, wherein the light irradiation device is configured to shift a reflection direction of the light by rotation of the mirror to divide the light into a plurality of segments and to form a light distribution pattern by linear scanning,

the light distribution pattern comprises a first line and a second line,

the mirror has a first reflecting surface for forming the first line and a second reflecting surface juxtaposed with the first reflecting surface in a rotational direction of the mirror for forming the second line,

the length of the first reflecting surface in the rotating direction is different from the length of the second reflecting surface in the rotating direction.

According to the above configuration, the first wire and the second wire can be made different in length. Therefore, a part of the light distribution pattern can be brighter than the other part.

In addition, in the light irradiation device of the present invention, it is also possible,

the second line is disposed between the plurality of first lines, and a length of the second reflecting surface in the rotational direction is longer than a length of the first reflecting surface in the rotational direction.

According to the above configuration, the light intensity of the line in the central region can be made different from the light intensity of the line in the other region in the vertical direction of the light distribution pattern.

the first reflecting surface is formed by a convex curved surface.

According to the above configuration, the line in the central region of the light distribution pattern can be made brighter than the lines in the other regions.

the second reflecting surface is formed of a concavely curved surface.

the second line is formed to overlap with a part of the first line in the left-right direction of the light distribution pattern.

According to the above configuration, a part of the light distribution pattern can be brighter than the other parts with a simple configuration.

the mirror is a polygon mirror including at least the first reflecting surface and the second reflecting surface.

The mirror is preferably a polygonal mirror.

Effect of the utility model

According to the present invention, a light irradiation device that can make a part of a light distribution pattern brighter than other parts can be provided.

Drawings

Fig. 1 is a horizontal sectional view of a vehicle headlamp.

Fig. 2 is a perspective view schematically showing the configuration of the optical unit of the reference embodiment.

Fig. 3 is a top view of the optical unit of fig. 2.

Fig. 4 is a side view of the optical unit of fig. 2.

Fig. 5 is a side view showing a state in which the rotating mirror is rotated in the optical unit of fig. 4.

Fig. 6 is a schematic view showing an example of a light distribution pattern formed in front of the vehicle by the optical unit of fig. 2.

Fig. 7 is a plan view of the optical unit of the first embodiment.

Fig. 8 is a plan view showing a state in which the rotating mirror is rotated in the optical unit of fig. 7.

Fig. 9 is a schematic view showing an example of a light distribution pattern formed in front of the vehicle by the optical unit of fig. 7.

Fig. 10 is a plan view of an optical unit according to a first modification.

Fig. 11 is a plan view showing a state in which the rotating mirror is rotated in the optical unit of fig. 10.

Fig. 12 is a schematic view showing an example of a light distribution pattern formed in front of the vehicle by the optical unit of fig. 10.

Fig. 13 is a plan view of an optical unit according to a second modification.

Fig. 14 is a plan view showing a state in which the rotating mirror is rotated in the optical unit of fig. 13.

Fig. 15 is a schematic view showing an example of a light distribution pattern formed in front of the vehicle by the optical unit of fig. 13.

Fig. 16 is a plan view of an optical unit according to a third modification.

Fig. 17 is a plan view showing a state in which the rotating mirror is rotated in the optical unit of fig. 16.

Fig. 18 is a schematic view showing an example of a light distribution pattern formed in front of the vehicle by the optical unit of fig. 16.

Fig. 19 is a side view of an optical unit of a fourth modification.

Description of the reference numerals

10: vehicle headlamp

20: dipped beam lamp unit

30: lamp unit for high beam

32: light source

34. 134, 144, 154, 164: rotating mirror

36: plano-convex lens (projection lens)

38: phosphor

130. 140, 150, 160: lamp unit

134a to 134f, 144a to 144f, 154a to 154f, and 164a to 164 j: reflecting surface

500: rotating mirror (rotating reflector)

501 a: blade (one example of reflecting surface)

P1-P5: light distribution pattern

LA 1-LF 1: thread

Wa, Wb: angle of diffusion

Detailed Description

The present invention will be described below with reference to the accompanying drawings based on embodiments. The same or equivalent constituent elements, components, and processes shown in the respective drawings are denoted by the same reference numerals, and overlapping descriptions are appropriately omitted. The embodiments do not limit the invention, but exemplify the invention, and all the features or combinations thereof described in the embodiments are not necessarily essential to the invention.

The "left-right direction", "front-back direction", and "up-down direction" in the present embodiment refer to relative directions set for the vehicle headlamp shown in fig. 1 for convenience of description. The "front-rear direction" is a direction including the "front direction" and the "rear direction". The "left-right direction" is a direction including the "left direction" and the "right direction". The "up-down direction" is a direction including the "up direction" and the "down direction".

The optical unit (an example of a light irradiation device) of the present invention can be used for various vehicle lamps. First, a vehicle headlamp capable of mounting an optical unit according to each embodiment described later will be described.

[ vehicle headlamp ]

Fig. 1 is a horizontal sectional view of a vehicle headlamp. Fig. 2 is a perspective view schematically showing the configuration of an optical unit mounted in the vehicle headlamp of fig. 1. Fig. 3 is a plan view of the optical unit, and fig. 4 and 5 are side views of the optical unit.

The vehicle headlamp 10 shown in fig. 1 is a right-side headlamp mounted on the right side of the front end of the vehicle, and has the same structure as the left-side headlamp except for being bilaterally symmetrical. Therefore, the right vehicle headlamp 10 will be described in detail below, and the left vehicle headlamp will not be described in detail.

As shown in fig. 1, the vehicle headlamp 10 includes a lamp body 12, and the lamp body 12 has a recess that opens toward the front. The front opening of the lamp body 12 is covered with a transparent front cover 14 to form a lamp chamber 16. The lamp house 16 functions as a space for accommodating the two

lamp units

20 and 30 arranged in the vehicle width direction.

The lamp unit 20 disposed on the lower side shown in fig. 1 of the vehicle headlamp 10 on the inner side in the vehicle width direction, that is, the right side of the

lamp units

20 and 30 is configured to emit low beam. On the other hand, the lamp unit 30 disposed on the upper side shown in fig. 1 of the vehicle headlamp 10 on the right side, which is the outer side in the vehicle width direction, of the

lamp units

20 and 30 is a lamp unit including a lens 36, and is configured to irradiate variable high beam.

The low-beam lamp unit 20 has a reflector 22 and a light source 24, which is formed, for example, from an LED. The reflector 22 and the LED light source 24 are supported to be tiltable with respect to the lamp body 12 by a known mechanism, for example, a mechanism using a sighting adjustment screw and a nut, which is not shown.

(reference embodiment)

As shown in fig. 2 to 5, the lamp unit 30 for high beam according to the embodiment includes a light source 32, a rotating mirror 34 as a reflector, a plano-convex lens 36 as a projection lens disposed in front of the rotating mirror 34, and a fluorescent material 38 disposed between the rotating mirror 34 and the plano-convex lens 36.

As the light source 32, for example, a laser light source can be used. Instead of the laser light source, a semiconductor light emitting element such as an LED or an EL element can be used as the light source. The light source 32 can be controlled to be turned on or off by a light source control unit, not shown. In particular, in the control of the light distribution pattern described later, it is preferable to use a light source that can be turned on and off with high accuracy in a short time. For example, at least one Electronic Control Unit (ECU). The electronic control unit may also include at least one microcontroller having one or more processors and one or more memories, and other electronic circuits having active elements such as transistors and passive elements. The processor is, for example, a CPU (Central Processing Unit), an MPU (micro Processing Unit), and/or a GPU (graphics Processing Unit). The memory includes ROM (read Only memory) and RAM (random Access memory). The ROM may also store a control program for the lamp unit 30.

The shape of the plano-convex lens 36 may be appropriately selected according to the required light distribution characteristics such as the light distribution pattern and the illuminance distribution, but an aspherical lens or a free-form lens may be used. The rear focal point of the plano-convex lens 36 is set, for example, in the vicinity of the light emitting surface of the phosphor 38. Thereby, the light image on the light emitting surface of the fluorescent material 38 is inverted vertically and is irradiated forward.

The phosphor 38 is made of, for example, a resin material mixed with phosphor powder that is excited by the blue laser light emitted from the light source 32 to emit yellow light. The blue laser light and the yellow fluorescent light are mixed, and the laser light emitted from the fluorescent material 38 becomes white light.

The rotary mirror 34 is rotatably connected to a motor 40 as a drive source. The rotating mirror 34 is rotated in the rotation direction D around the rotation axis R by a motor 40. The rotation axis R of the rotating mirror 34 is inclined with respect to the optical axis Ax (see fig. 4). The rotating mirror 34 is composed of a plurality of (12 surfaces in this example) reflecting surfaces 34a to 34l arranged in the rotating direction D. The reflection surfaces 34a to 34l of the rotating mirror 34 reflect the light emitted from the light source 32 while rotating. Thereby, as shown in fig. 4, scanning of light using the light source 32 can be performed. The rotating mirror 34 is, for example, a polygon mirror having a 12-sided reflection surface formed in a polygon shape.

Here, the reflecting surface 34A and the reflecting surface 34g located on the diagonally opposite side from the reflecting surface 34A among the reflecting surfaces 34A to 34h are set as the first reflecting surface pair 34A. The reflecting surface 34B and the reflecting surface 34h located on the diagonally opposite side from the reflecting surface 34B are set as a second reflecting surface pair 34B. The reflecting surface 34C and the reflecting surface 34i located on the diagonally opposite side from the reflecting surface 34C are set as a third reflecting surface pair 34C. The reflecting surface 34D and the reflecting surface 34j located on the diagonally opposite side from the reflecting surface 34D are set as a fourth reflecting surface pair 34D. The reflecting surface 34E and the reflecting surface 34k located on the diagonally opposite side from the reflecting surface 34E are set as a fifth reflecting surface pair 34E. The reflection surface 34F and the reflection surface 34l located on the diagonally opposite side from the reflection surface 34F are set as a sixth reflection surface pair 34F.

The first reflecting surface pair 34A is formed so that an angle θ a formed by the reflecting surface 34A and the optical axis Ax on a surface constituted by the vertical direction and the front-rear direction when the laser light from the light source 32 is reflected by the reflecting surface 34A (that is, in the case of the arrangement relationship shown in fig. 3 and 4) and an angle formed by the reflecting surface 34g and the optical axis Ax on a surface constituted by the vertical direction and the front-rear direction when the laser light from the light source 32 is reflected by the reflecting surface 34g are substantially the same. Similarly, the second reflecting surface pair 34B is formed so that the angle θ B between the optical axis Ax and the reflecting surface 34B on the surface constituted by the vertical direction and the front-rear direction when the laser light from the light source 32 is reflected by the reflecting surface 34B (that is, in the case of the arrangement relationship shown in fig. 5) and the angle between the optical axis Ax and the reflecting surface 34h on the surface constituted by the vertical direction and the front-rear direction when the laser light from the light source 32 is reflected by the reflecting surface 34h are substantially the same. The third reflecting surface pair 34C is formed so that the angle formed by the reflecting surface 34C and the optical axis Ax when the laser light from the light source 32 is reflected by the reflecting surface 34C is substantially the same as the angle formed by the reflecting surface 34i and the optical axis Ax when the laser light from the light source 32 is reflected by the reflecting surface 34 i. The fourth reflecting surface pair 34D is formed so that the angle formed by the reflecting surface 34D and the optical axis Ax when the laser beam from the light source 32 is reflected by the reflecting surface 34D is substantially the same as the angle formed by the reflecting surface 34j and the optical axis Ax when the laser beam from the light source 32 is reflected by the reflecting surface 34 j. The fifth reflecting surface pair 34E is formed so that the angle formed by the reflecting surface 34E and the optical axis Ax when the laser light from the light source 32 is reflected by the reflecting surface 34E and the angle formed by the reflecting surface 34k and the optical axis Ax when the laser light from the light source 32 is reflected by the reflecting surface 34k are substantially the same. The sixth reflecting surface pair 34F is formed so that the angles formed by the reflecting surfaces 34F, 34l of the laser beam from the light source 32 and the optical axis Ax are substantially the same. That is, the reflecting surfaces 34a to 34l of the rotating mirror 34 are inclined surfaces in which a pair of reflecting surfaces located on diagonal lines have the same angle. Thus, the light reflected by the pair of reflection surfaces constituting the first to sixth reflection surface pairs 34A to 34F, respectively, is irradiated to substantially the same position in the vertical direction in front of the vehicle. Further, the wobbling of the rotating mirror 34 when the rotating mirror 34 is rotated in the rotating direction D by the motor 40 can be prevented.

The angle θ a between the first reflecting surface pair 34A and the optical axis Ax when the laser light from the light source 32 is reflected by the first reflecting surface pair 34A is different from the angles between the optical axis Ax and the respective reflecting surfaces of the other reflecting surface pairs 34B to 34F when the laser light from the light source 32 is reflected by the other reflecting surface pairs 34B to 34F. For example, an angle θ b between the reflection surface 34b and the optical axis Ax shown in fig. 5 is formed slightly smaller than an angle θ a between the reflection surface 34a and the optical axis Ax shown in fig. 4. Similarly, the angles formed by the respective reflection surface pairs and the optical axis Ax become smaller in the order of the second reflection surface pair 34B, the third reflection surface pair 34C, the fourth reflection surface pair 34D, the fifth reflection surface pair 34E, and the sixth reflection surface pair 34F. Thus, the light reflected by one of the pair of reflection surfaces is irradiated to a position different from the other pair of reflection surfaces in the up-down direction in front of the vehicle. For example, the light Lb reflected by the reflection surface 34b is irradiated on the virtual vertical screen in front of the vehicle to a position above the light La reflected by the reflection surface 34 a.

The light reflected by the respective reflection surfaces 34a to 34l of the rotating mirror 34 configured as described above and transmitted through the plano-convex lens 36 via the fluorescent body 38 forms a light distribution pattern P1 as shown in fig. 6 on a virtual vertical screen at a predetermined position in front of the vehicle (for example, in front of 25m of the vehicle). Specifically, the light reflected by the first reflecting surface pair 34A (the reflecting surfaces 34A and 34g) forms the lowermost line LA1 in the light distribution pattern P1 shown in fig. 6. In addition, a line LB1 is formed above the line LA1 by the light reflected by the second reflection surface pair 34B (reflection surfaces 34B, 34 h). The line LC1 is formed on the upper side of the line LB1 by the light reflected by the third pair of reflection surfaces 34C (reflection surfaces 34C, 34 i). The line LD1 is formed on the upper side of the line LC1 by the light reflected by the fourth reflection surface pair 34D (reflection surfaces 34D, 34 j). The line LE1 is formed on the upper side of the line LD1 by the light reflected by the fifth reflection surface pair 34E (reflection surfaces 34E, 34 k). The line LF1 is formed on the upper side of the line LE1 by the light reflected by the sixth reflection surface pair 34F (reflection surfaces 34F, 34 l). In this way, the light reflection direction is shifted by the rotation of the rotating mirror 34, so that the light is divided into a plurality of segments and linearly scanned to form the light distribution pattern P1.

Further, when the laser light from the light source 32 is reflected at the boundary between the reflecting surfaces 34a to 34l, there is a possibility that the laser light is scattered to form an inappropriate light distribution. Therefore, it is preferable to control turning on and off of the light source 32 so that the light source 32 is turned off at a timing when the boundary between the reflecting surfaces 34a to 34l of the light source control unit intersects with the beam of the laser light from the light source 32.

The light source 32 provided in the lamp unit 30 of the reference embodiment is relatively small, and the position where the light source 32 is disposed is also shifted from the optical axis Ax between the rotating mirror 34 and the planoconvex lens 36. Therefore, the length of the vehicle headlamp 10 in the vehicle front-rear direction can be shortened as compared with a case where the light source, the reflector, and the lens are aligned on the optical axis as in the conventional projector type lamp unit.

(first embodiment)

Fig. 7 and 8 show plan views of the lamp unit 130 according to the first embodiment.

As shown in fig. 7 and 8, the lamp unit 130 includes the light source 32, the rotating mirror 134, the plano-convex lens 36, and the fluorescent material 38.

The rotating mirror 134 in the first embodiment is configured by a plurality of (6 surfaces in this example) reflecting surfaces 134a to 134f arranged side by side in the rotation direction D. The reflection surfaces 134a to 134f are all formed in a planar shape, and the lengths of the surfaces along the rotation direction D are formed to be different. In this example, as shown in fig. 7, the length xb of the surface along the rotational direction D of the reflection surfaces 134b and 134e (an example of the second reflection surface) is formed longer than the length xa of the surface along the rotational direction D of the reflection surfaces 134a, 134c, 134D, and 134f (an example of the first reflection surface). The lengths xa of the surfaces along the rotation direction D of the reflection surfaces 134a and 134D disposed at the opposing positions are equal to each other. Similarly, the lengths xa of the surfaces along the rotation direction D of the reflection surfaces 134c and 134f disposed at the opposing positions are equal to each other. Similarly, the lengths xb of the surfaces along the rotation direction D of the reflection surfaces 134b and 134e disposed at the opposing positions are formed to be equal. The lengths xa of the surfaces of the reflection surfaces 134a, 134c, 134D, and 134f along the rotation direction D are equal to each other.

Therefore, if the speed of rotation of the rotating mirror 134 in the rotation direction D is constant, for example, the diffusion angle Wb (see fig. 8) in the left-right direction of the laser light reflected by the reflecting surface 134b formed to have a longer surface length in the rotation direction D is wider than the diffusion angle Wa (see fig. 7) in the left-right direction of the laser light reflected by the reflecting surface 134a formed to have a shorter surface length than the reflecting surface 134 b.

An angle θ a formed by the reflecting surface 134a and the optical axis Ax when the laser light from the light source 32 is reflected by the reflecting surface 134a is different from angles formed by the reflecting surfaces of the other reflecting surfaces 134b to 134f and the optical axis Ax when the laser light from the light source 32 is reflected by the other reflecting surfaces 134b to 134f (see fig. 4 and 5). For example, an angle θ c formed between the reflecting surface 134c and the optical axis Ax is formed slightly smaller than an angle θ a formed between the reflecting surface 134a and the optical axis Ax. Similarly, the angle formed by each reflecting surface and the optical axis Ax becomes smaller in the order of the reflecting surface 134b, the reflecting surface 134e, the reflecting surface 134d, and the reflecting surface 134 f. Thus, the light reflected by one reflecting surface is irradiated to a position different from the other reflecting surfaces in the up-down direction in front of the vehicle. For example, the light reflected by the reflecting surface 134c is irradiated on the virtual vertical screen in front of the vehicle to a position above the light reflected by the reflecting surface 134 a. The light reflected by the reflecting surface 134b is irradiated on the virtual vertical screen at a position above the light reflected by the reflecting surface 134 c.

Fig. 9 shows a light distribution pattern P2 formed on a virtual screen in front of the vehicle (for example, in front of 25 mm) by the lamp unit 130 of the first embodiment.

As shown in fig. 9, the light distribution pattern P2 includes a plurality of lines (LA2 to LF2) formed by laser light. The laser light emitted from the light source 32 is reflected by the reflecting surfaces 134a to 134f of the rotating mirror 134, and passes through the plano-convex lens 36 via the fluorescent material 38. As in the reference embodiment, the rear focus of the planoconvex lens 36 is set on the light exit surface of the phosphor 38, and therefore the light image of the light exit surface of the phosphor 38 is inverted vertically and irradiated forward.

Specifically, the laser light reflected by the reflection surface 134a forms a lowermost line LA2 in the light distribution pattern P2 shown in fig. 9. Further, line LC2 is formed above line LA2 by the laser light reflected by reflection surface 134 c. The line LB2 is formed above the line LC2 by the laser light reflected by the reflection surface 134 b. The laser beam reflected by the reflecting surface 134e forms a line LE2 above the line LB 2. The laser beam reflected by the reflection surface 134d forms a line LD2 above the line LE 2. The laser beam reflected by the reflection surface 134f forms a line LF2 above the line LD 2. Further, the length of the left-right direction scan of the line LB2 at the third stage from below and the line LE2 at the fourth stage is formed longer than the length of the left-right direction scan of the line LA2 at the first stage from below, the line LC2 at the second stage, the line LD2 at the fifth stage, and the line LF2 at the sixth stage.

In addition, at the boundary between the reflecting surfaces 134a to 134f, there is a possibility that the laser light is scattered to form an inappropriate light distribution, as in the above-described reference embodiment. Therefore, the light source control unit preferably controls turning on and off of the light source 32 so that the light source 32 is turned off at a timing at which the boundary between the reflecting surfaces 134a to 134f intersects with the beam of the laser light from the light source 32.

In this example, the rotating mirror 134 is configured by a polygon mirror having 6 surfaces, but the present invention is not limited to this. For example, as in the reference embodiment, the polygon mirror may be configured by a polygon mirror having 12 surfaces and a pair of reflection surfaces located on diagonal lines may be inclined at the same angle. In this example, the lowermost line LA2, the upper line LC2, the uppermost line LF2 and the lower line LD2 of the shorter lines constituting the light distribution pattern P2 are formed by the reflection surfaces 134a, 134c, 134f, 134d, respectively. The line LA2, the line LC2, the line LD2, and the line LF2, which are short lines, may be formed by any one of the reflection surfaces 134a, 134c, 134d, and 134 f.

However, in the optical unit using the polygon mirror, when the diffusion angle of the light reflected by the reflection surface is widened to increase the light distribution pattern formed in front of the vehicle, for example, it is conceivable to increase the distance between the polygon mirror and the fluorescent material. However, when the distance between the polygon mirror and the phosphor is increased, for example, if a regular polygon mirror is used, the total length of the optical unit becomes longer. Further, the illuminance of the light distribution pattern decreases, and visibility in the distance decreases.

In contrast, the lamp unit 130 of the first embodiment includes the first reflecting surface and the second reflecting surface having different lengths of surfaces along the rotation direction D among the plurality of reflecting surfaces in which the rotating mirrors 134 are arranged in the rotation direction D. Specifically, the length xb of the surface of the reflection surfaces 134b, 134e along the rotation direction D is formed longer than the length xa of the surface of the reflection surfaces 134a, 134c, 134D, 134f along the rotation direction D. Therefore, according to the configuration of the lamp unit 130, the diffusion angle of the laser light reflected by the reflection surfaces 134b and 134e in the left-right direction is wider than the diffusion angle of the laser light reflected by the reflection surfaces 134a, 134c, 134d, and 134f in the left-right direction. Thus, as shown in fig. 9, the length of the scan in the left-right direction in the line LB2 and the line LE2 can be made longer than the length of the scan in the left-right direction in the line LA2, the line LC2, the line LD2, and the line LF 2.

As described above, by making the lengths of the lines LB2, LE2 (an example of the second line) longer than the lengths of the lines LA2, LC2, LD2, LF2 (an example of the first line), a light distribution pattern wide in the left-right direction can be formed in the central region in the vertical direction, and a light distribution pattern high in luminous intensity can be formed in the upper end region and the lower end region in the vertical direction. Therefore, the light intensity of the light distribution pattern in the central region, which is slightly reduced by forming a wide light distribution pattern in the central region, can be supplemented by the high light intensity of the light distribution pattern in the upper and lower regions, and a sufficiently high light intensity of the entire light distribution pattern P2 can be ensured. Further, since it is not necessary to increase the distance between the rotating mirror 134 and the fluorescent material 38 in order to increase the width of the light distribution pattern P2 in the left-right direction, the entire length of the lamp unit 130 itself does not become long. Further, since a part of the light distribution pattern can be made brighter than the other part by adjusting the shape of the reflection surface of the rotating mirror 134, it is not necessary to control the output of the light source 32, and control for forming the light distribution pattern becomes easy.

Next, a modified example of the lamp unit 130 of the first embodiment will be described.

(first modification)

Fig. 10 and 11 show plan views of a lamp unit 140 according to a first modification.

As shown in fig. 10 and 11, the lamp unit 140 includes the light source 32, the rotating mirror 144, the plano-convex lens 36, and the fluorescent material 38.

The rotating mirror 144 of the lamp unit 140 is composed of a plurality of (6 surfaces in this example) reflecting surfaces 144a to 144f arranged in parallel in the rotation direction D, similarly to the rotating mirror 134 of the first embodiment. The lengths of the surfaces of the reflecting surfaces 144a to 144f along the rotation direction D are formed to be different. The reflecting surfaces 144a to 144f are formed such that a part of the reflecting surfaces are concavely curved surfaces recessed toward the rotation axis R.

In this example, the lengths of the surfaces of the reflecting

surfaces

144b and 144e (an example of the second reflecting surface) along the rotating direction D are formed longer than the lengths of the surfaces of the reflecting

surfaces

144a, 144c, 144D and 144f (an example of the first reflecting surface) along the rotating direction D. The reflecting surfaces 144b and 144e, which have long surfaces along the rotation direction D, are formed as concavely curved surfaces. The lengths of the surfaces along the rotation direction D of the reflection surfaces 144a and 144D disposed at the opposing positions are equal to each other. Similarly, the lengths of the surfaces along the rotation direction D of the reflection surface 144c and the reflection surface 144f disposed at the opposing positions are formed to be equal. Similarly, the lengths of the surfaces along the rotation direction D of the reflection surfaces 144b and 144e disposed at the opposing positions are formed to be equal. The lengths of the surfaces of the reflecting

surfaces

144a, 144c, 144D, and 144f along the rotation direction D are equal to each other.

However, when the reflection surfaces are formed by the concave curved surfaces and the reflection surfaces are formed in a planar shape, for example, when the lengths of the surfaces along the rotation direction D of the two reflection surfaces are equal, the diffusion angle in the left-right direction of the laser light reflected by the reflection surfaces of the concave curved surfaces is narrower than the diffusion angle in the left-right direction of the laser light reflected by the planar reflection surfaces. Therefore, in this example, the reflection surfaces 144b and 144e formed to have a long surface length in the rotation direction D are formed into concavely curved surfaces, and the reflection surfaces 144a, 144c, 144D, and 144f formed to have a short surface length in the rotation direction D are formed into flat surfaces, so that the diffusion angles in the left-right direction of the laser beams reflected by the reflection surfaces 144a to 144f (see, for example, Wa1 in fig. 10 and Wb1 in fig. 11) are all equal.

The angle θ a between the optical axis Ax and the reflecting surface 144a when the laser beam from the light source 32 is reflected by the reflecting surface 144a is different from the angles between the optical axis Ax and the reflecting surfaces 144b to 144f of the other reflecting surfaces 144b to 144f when the laser beam from the light source 32 is reflected by the other reflecting surfaces 144b to 144f (see fig. 4 and 5). For example, an angle θ c formed between the reflecting surface 144c and the optical axis Ax is slightly smaller than an angle θ a formed between the reflecting surface 144a and the optical axis Ax. Similarly, the angles formed by the respective reflection surfaces and the optical axis Ax become smaller in the order of the reflection surface 144b, the reflection surface 144e, the reflection surface 144d, and the reflection surface 144 f. Thus, the light reflected by one reflecting surface is irradiated to a position different from the other reflecting surfaces in the up-down direction in front of the vehicle. For example, the light reflected by the reflecting surface 144c is irradiated on the virtual vertical screen in front of the vehicle to a position above the light reflected by the reflecting surface 144 a. The light reflected by the reflecting surface 144b is irradiated on the virtual vertical screen to a position above the light reflected by the reflecting surface 144 c.

Fig. 12 shows a light distribution pattern P3 formed in front of the vehicle by the lamp unit 140 according to the first modification.

As shown in fig. 12, the light distribution pattern P3 includes a plurality of lines (LA3 to LF3) formed by laser light. The laser light emitted from the light source 32 is reflected by the reflecting surfaces 144a to 144f of the rotating mirror 144, and passes through the plano-convex lens 36 via the fluorescent material 38. As in the reference embodiment, since the rear focal point of the planoconvex lens 36 is set on the light emitting surface of the phosphor 38, the light image on the light emitting surface of the phosphor 38 is inverted vertically and is irradiated forward.

Specifically, the laser light reflected by the reflection surface 144a forms the lowermost line LA3 in the light distribution pattern P3 shown in fig. 12. Further, line LC3 is formed above line LA3 by the laser light reflected by reflection surface 144 c. The line LB3 is formed above the line LC3 by the laser light reflected by the reflection surface 144 b. The laser beam reflected by the reflecting surface 144e forms a line LE3 above the line LB 3. The laser beam reflected by the reflecting surface 144d forms a line LD3 above the line LE 3. The laser beam reflected by the reflecting surface 144f forms a line LF3 above the line LD 3. The lengths of the left and right scans on the lines LA3 to LF3 are all equal.

In this way, the lamp unit 140 of the first modification is configured such that the length of the surfaces along the rotational direction D of the reflecting

surfaces

144b, 144e in the rotating mirror 144 is longer than the length of the surfaces along the rotational direction D of the reflecting

surfaces

144a, 144c, 144D, 144f, and the long reflecting

surfaces

144b, 144e are configured by concavely curved surfaces. The laser beams reflected by the reflecting surfaces 144a to 144f are all configured to have the same diffusion angle in the left-right direction. The laser beams reflected by the reflecting

surfaces

144b, 144e having the concave curved surfaces travel closer to the optical axis Ax than the laser beams reflected by the reflecting

surfaces

144a, 144c, 144d, 144f having the flat surfaces. Therefore, when the speed of rotation of the rotating mirror 144 in the rotation direction D is constant, the luminous intensities of the lines LB3, LE3 (an example of the second line) formed by the laser light reflected by the reflecting

surfaces

144b, 144e are higher than the luminous intensities of the lines LA3, LC3, LD3, LF3 (an example of the first line) formed by the laser light reflected by the reflecting

surfaces

144a, 144c, 144D, 144 f. Thus, according to the configuration of the lamp unit 140, the light intensity in the central region in the vertical direction of the light distribution pattern P3 can be made higher than the light intensity in the upper and lower regions.

(second modification)

Fig. 13 and 14 show plan views of a lamp unit 150 according to a second modification.

As shown in fig. 13 and 14, the lamp unit 150 includes the light source 32, the rotating mirror 154, the plano-convex lens 36, and the fluorescent material 38.

The rotating mirror 154 of the lamp unit 150 is composed of a plurality of (6 surfaces in this example) reflecting surfaces 154a to 154f arranged side by side in the rotation direction D, similarly to the rotating mirror 134 of the first embodiment. The reflecting surfaces 154a to 154f are formed so that the lengths of the surfaces along the rotation direction D are different. The reflecting surfaces 154a to 154f are formed such that a part of the reflecting surfaces are convexly curved surfaces protruding outward of the rotating mirror 154.

In this example, the lengths of the surfaces of the reflecting surfaces 154a and 154D (an example of the second reflecting surface) along the rotating direction D are formed longer than the lengths of the surfaces of the reflecting

surfaces

154b, 154c, 144e, and 154f (an example of the first reflecting surface) along the rotating direction D. The reflecting

surfaces

154b, 154c, 144e, and 154f having short surface lengths along the rotation direction D are formed as convexly curved surfaces. The lengths of the surfaces along the rotation direction D of the reflection surfaces 154a and 154D disposed at the opposing positions are formed to be equal to each other. Similarly, the lengths of the surfaces along the rotation direction D of the reflection surface 154c and the reflection surface 154f disposed at the opposing positions are formed to be equal. Similarly, the lengths of the surfaces along the rotation direction D of the reflection surfaces 154b and 154e disposed at the opposing positions are formed to be equal. The lengths of the surfaces of the reflecting

surfaces

154b, 154c, 154e, and 154f along the rotation direction D are equal to each other.

However, when the reflecting surfaces are formed by the convex curved surfaces and the reflecting surfaces are formed in a planar shape, for example, when the lengths of the surfaces along the rotation direction D of the two reflecting surfaces are equal, the diffusion angle in the left-right direction of the laser light reflected by the reflecting surfaces of the convex curved surfaces is wider than the diffusion angle in the left-right direction of the laser light reflected by the reflecting surfaces of the planar shape. Therefore, in this example, the reflecting

surfaces

154b, 154c, 154e, and 154f having the shorter surface lengths in the rotation direction D are formed into convexly curved surfaces, and the reflecting surfaces 154a and 154D having the longer surface lengths in the rotation direction D are formed into planar surfaces, so that the diffusion angles of the laser beams reflected by the reflecting surfaces 154a to 154f in the left-right direction (see, for example, Wa2 in fig. 13 and Wb2 in fig. 14) are all equal.

The angle θ a between the optical axis Ax and the reflecting surface 154a when the laser beam from the light source 32 is reflected by the reflecting surface 154a is different from the angles between the optical axis Ax and the reflecting surfaces 154b to 154f of the other reflecting surfaces 154b to 154f when the laser beam from the light source 32 is reflected by the other reflecting surfaces 154b to 154f (see fig. 4 and 5). For example, an angle θ c formed between the reflecting surface 154c and the optical axis Ax is slightly smaller than an angle θ b formed between the reflecting surface 154b and the optical axis Ax. Similarly, the angle formed by each reflecting surface and the optical axis Ax becomes smaller in the order of the reflecting surface 154a, the reflecting surface 154d, the reflecting surface 154e, and the reflecting surface 154 f. Thus, the light reflected by one reflecting surface is irradiated to a position different from the other reflecting surfaces in the up-down direction in front of the vehicle. For example, the light reflected by the reflecting surface 154c is irradiated on the virtual vertical screen in front of the vehicle to a position above the light reflected by the reflecting surface 154 b. The light reflected by the reflecting surface 154a is irradiated on the virtual vertical screen to a position above the light reflected by the reflecting surface 154 c.

Fig. 15 shows a light distribution pattern P4 formed in front of the vehicle by the lamp unit 150 according to the second modification.

As shown in fig. 15, the light distribution pattern P4 includes a plurality of lines (LA4 to LF4) formed by laser light. The laser light emitted from the light source 32 is reflected by the reflecting surfaces 154a to 154f of the rotating mirror 154, and passes through the plano-convex lens 36 via the fluorescent material 38. As in the reference embodiment, since the rear focal point of the planoconvex lens 36 is set on the light emitting surface of the phosphor 38, the light image on the light emitting surface of the phosphor 38 is inverted vertically and is irradiated forward.

Specifically, the laser beam reflected by the reflection surface 154b forms a lowermost line LB4 in the light distribution pattern P4 shown in fig. 15. Further, a line LC4 is formed above the line LB4 by the laser light reflected by the reflection surface 154 c. The laser light reflected by the reflection surface 154a forms a line LA4 on the upper side of the line LC 4. Line LD4 is formed above line LA4 by the laser light reflected by reflection surface 154 d. The laser beam reflected by the reflecting surface 154e forms a line LE4 above the line LD 4. The laser beam reflected by the reflecting surface 154f forms a line LF4 above the line LE 4. The scanning lengths in the left-right direction of the lines LB4 to LF4 are all equal.

In this way, the lamp unit 150 according to the second modification is configured such that the reflecting surfaces 154a and 154D of the rotating mirror 154 have longer surfaces along the rotation direction D than the reflecting

surfaces

154b, 154c, 144e, and 154f, and the reflecting

surfaces

154b, 154c, 144e, and 154f having shorter lengths are formed by convexly curved surfaces. The laser beams reflected by the reflecting surfaces 154a to 154f are configured to have the same diffusion angle in the left-right direction. The laser light reflected by the reflecting

surfaces

154b, 154c, 144e, and 154f having the convex curved surfaces travels more diffusely from the optical axis Ax than the laser light reflected by the reflecting

surfaces

154a and 154d having the flat surfaces. Therefore, when the speed of rotation of the rotating mirror 154 in the rotation direction D is constant, the luminous intensities of the lines LA4, LD4 (an example of the second line) formed by the laser light reflected by the reflecting surfaces 154a, 154D are higher than the luminous intensities of the lines LB4, LC4, LE4, LF4 (an example of the first line) formed by the laser light reflected by the reflecting

surfaces

154b, 154c, 144e, 154 f. Thus, according to the configuration of the lamp unit 150, the light intensity in the central region in the vertical direction of the light distribution pattern P4 can be made higher than the light intensity in the upper and lower regions.

(third modification)

Fig. 16 and 17 show plan views of a lamp unit 160 according to a third modification.

As shown in fig. 16 and 17, the lamp unit 160 includes the light source 32, the rotating mirror 164, the plano-convex lens 36, and the fluorescent material 38.

The rotating mirror 164 in the third modification is configured by a plurality of (10 surfaces in this example) reflecting surfaces 164a to 164j arranged side by side in the rotation direction D. The reflecting surfaces 164a to 164j are all formed in a planar shape, and the lengths of the surfaces along the rotation direction D are formed to be different. In this example, the lengths of the surfaces along the rotation direction D of the reflection surfaces 164a, 164b, 164c, 164f, 164g, and 164h (an example of the first reflection surface) are formed longer than the lengths of the surfaces along the rotation direction D of the reflection surfaces 164D, 164e, 164i, and 164j (an example of the second reflection surface). The lengths of the surfaces along the rotation direction D of the reflection surfaces 164a and 164f disposed at the opposing positions are formed to be equal to each other. Similarly, the lengths of the surfaces along the rotation direction D of the reflection surfaces 164b and 164g, and the reflection surfaces 164c and 164h disposed at the opposing positions are equal to each other. Similarly, the lengths of the surfaces along the rotation direction D of the reflection surfaces 164D and 164i, and the reflection surfaces 164e and 164j disposed at the opposing positions are equal to each other. The lengths of the surfaces of the reflection surfaces 164a, 164b, 164c, 164f, 164g, and 164h along the rotation direction D are equal to each other. The lengths of the surfaces of the reflection surfaces 164D, 164e, 164i, and 164j along the rotation direction D are equal to each other.

Therefore, if the speed of rotation of the rotating mirror 164 in the rotation direction D is constant, for example, the diffusion angle Wa3 in the left-right direction (see fig. 16) of the laser light reflected by the reflection surface 164a formed to have a longer length along the rotation direction D is wider than the diffusion angle Wb3 in the left-right direction (see fig. 17) of the laser light reflected by the reflection surface 164D formed to have a shorter length than the reflection surface 164 a.

The angle θ a between the optical axis Ax and the reflecting surface 164a when the laser light from the light source 32 is reflected by the reflecting surface 164a is different from the angles between the optical axis Ax and the other reflecting

surfaces

164b, 164c, 164f, 164g, and 164h when the laser light from the light source 32 is reflected by the other reflecting surfaces (see fig. 4 and 5). An angle formed by the reflection surfaces 164d, 164e, 164i, and 164j and the optical axis Ax when the laser light from the light source 32 is reflected by the reflection surfaces 164d, 164e, 164i, and 164j is the same as any one of angles formed by the reflection surfaces 164a, 164b, 164c, 164f, 164g, and 164h and the optical axis Ax when the laser light from the light source 32 is reflected by the reflection surfaces 164a, 164b, 164c, 164f, 164g, and 164h

For example, an angle θ b formed between the reflecting surface 164b and the optical axis Ax is slightly smaller than an angle θ a formed between the reflecting surface 164a and the optical axis Ax. Similarly, the angle formed by each reflecting surface and the optical axis Ax becomes smaller in the order of the reflecting surface 164c, the reflecting surface 164f, the reflecting surface 164g, and the reflecting surface 164 h. Thus, the light reflected by one reflecting surface is irradiated to a position different from the other reflecting surfaces in the up-down direction in front of the vehicle. For example, the light reflected by the reflecting surface 164b is irradiated to a position lower than the light reflected by the reflecting surface 164a on the virtual vertical screen in front of the vehicle. The light reflected by the reflecting surface 164c is irradiated on the virtual vertical screen to a position below the light reflected by the reflecting surface 164 b.

An angle formed by the reflecting surface 164d and the optical axis Ax is the same as an angle formed by the reflecting surface 164b and the optical axis Ax. An angle formed by the reflection surface 164e and the optical axis Ax is the same as an angle formed by the reflection surface 164c and the optical axis Ax. An angle formed by the reflection surface 164i and the optical axis Ax is the same as an angle formed by the reflection surface 164f and the optical axis Ax. An angle formed by the reflecting surface 164j and the optical axis Ax is the same as an angle formed by the reflecting surface 164g and the optical axis Ax. Thus, for example, the light reflected by the reflecting surface 164d is irradiated in the same direction as the light reflected by the reflecting surface 164 b. Similarly, the light reflected by the reflecting

surfaces

164e, 164i, and 164j and the light reflected by the reflecting

surfaces

164c, 164f, and 164g are irradiated in the same direction.

Fig. 18 shows a light distribution pattern P5 formed in front of the vehicle by the lamp unit 160 of the third modification.

As shown in fig. 18, the light distribution pattern P5 includes a plurality of lines (LA5 to LJ5) formed by laser light. The laser light emitted from the light source 32 is reflected by the reflection surfaces 164a to 164j of the turning mirror 164, and passes through the plano-convex lens 36 via the fluorescent material 38. As in the reference embodiment, since the rear focal point of the planoconvex lens 36 is set on the light emitting surface of the phosphor 38, the light image on the light emitting surface of the phosphor 38 is inverted vertically and is irradiated forward.

Specifically, the laser light reflected by the reflection surface 164a forms a lowermost line LA5 in the light distribution pattern P5 shown in fig. 18. Further, a line LB5 is formed above the line LA5 by the laser beam reflected by the reflection surface 164 b. The line LC5 is formed above the line LB5 by the laser light reflected by the reflection surface 164 c. The line LF5 is formed above the line LC5 by the laser light reflected by the reflection surface 164 f. The laser beam reflected by the reflecting surface 164g forms a line LG5 above the line LF 5. A line LH5 is formed above line LG5 by the laser light reflected by reflecting surface 164 h. Then, the line LD5 is formed so as to overlap a part of the line LB5 with the laser light reflected by the reflection surface 164 d. The line LE5 is formed to overlap a part of the line LC5 by the laser light reflected by the reflection surface 164 e. The line LI5 is formed to overlap a part of the line LF5 by the laser light reflected by the reflection surface 164 i. The line LJ5 is formed so as to overlap a part of the line LG5 by the laser light reflected by the reflecting surface 164 j.

The lengths of the left and right scanning of the lines LA5, LB4, LC5, LF5, LG5, and LH5 are equal. The lines LD5, LE5, LI5, and LJ5 are formed to have equal scanning lengths in the left-right direction. Lines LD5, LE5, LI5, and LJ5 are formed to overlap the center portions of lines LB5, LC5, LF5, and LG5 in the left-right direction, respectively.

In this way, the lamp unit 160 according to the third modification is configured such that the length of the surface along the rotation direction D of the reflection surfaces 164a, 164b, 164c, 164f, 164g, and 164h of the rotating mirror 164 is longer than the length of the surface along the rotation direction D of the reflection surfaces 164D, 164e, 164i, and 164j, and the angles formed by the reflection surfaces 164D, 164e, 164i, and 164j having short lengths and the optical axis Ax are equal to the angles formed by the reflection surfaces 164b, 164c, 164f, and 164g having long lengths and the optical axis Ax, respectively. Thus, lines LD5, LE5, LI5, and LJ5 (an example of a second line) of the light distribution pattern P5 formed by the reflection surfaces 164d, 164e, 164i, and 164j can be overlapped with parts of lines LB5, LC5, LF5, and LG5 (an example of a first line) formed by the reflection surfaces 164b, 164c, 164f, and 164g, respectively. Thus, according to the configuration of the lamp unit 160, for example, the central region in the light distribution pattern P5 can be made brighter than the peripheral region in the light distribution pattern P5 with a simple configuration.

In the first to third modifications, the control of the turning on and off of the light source at the boundary between the reflecting surfaces, the number of reflecting surfaces constituting the rotating mirror, the inclination angle thereof, and the lines forming the light distribution pattern by which reflecting surface, and the like are the same as those of the lamp unit 130 according to the first embodiment.

(fourth modification)

Fig. 19 shows a lamp unit 530 of a fourth modification.

As shown in fig. 19, a rotating mirror (rotating reflector) 500 of a blade scanning (registered trademark) system may be used instead of the polygon mirror 134 used in the above-described embodiment. The rotary mirror 500 includes a plurality of (three in fig. 13) blades 501a and a cylindrical rotating portion 501 b. Each blade 501a is provided around the rotating portion 501b and functions as a reflecting surface. The rotating mirror 500i is disposed such that the rotation axis R thereof is inclined with respect to the optical axis Ax.

The blade 501a has a shape twisted so that an angle formed by the optical axis Ax and the reflecting surface changes in the circumferential direction around the rotation axis R. This enables scanning using light from the light source 32, as with the polygon mirror 134.

At least one blade 501a (an example of a first reflecting surface) of the plurality of blades 501a has a length in the rotating direction of the rotating mirror 500 different from the length of the other blades 501a (an example of a second reflecting surface) in the rotating direction. In the case of using the rotating mirror 500, as in the above-described embodiment, the lengths in the left-right direction of the lines forming the light distribution pattern can be made different from each other, and a part of the light distribution pattern can be made brighter than the other parts.

In addition, not only the lengths of the blades 501a in the rotation direction but also the shapes (curvatures and the like) of the blades 501a may be different from each other.

The present invention has been described above with reference to the above embodiments, but the present invention is not limited to the above embodiments, and the present invention also includes a configuration in which the components of the embodiments are appropriately combined and replaced. Further, the combination and the order of processing in the embodiments may be appropriately rearranged or various modifications such as design changes may be applied to the embodiments according to the knowledge of those skilled in the art, and embodiments to which such modifications are applied are also included in the scope of the present invention.

In the above-described embodiments, the case where the lamp unit is mounted on the vehicle headlamp has been described, but the present invention is not limited to this example. The optical unit including the light source and the rotating mirror described above may be applied to a component of a sensor unit (e.g., laser radar, LiDAR, etc.) mounted on a vehicle. In this case, the sensor sensitivity in a specific region in the sensor target range can be improved by making the lengths (lengths in the rotational direction) of the reflecting surfaces of the rotating mirrors different.

Claims

1. A light irradiation device comprising a light source and a rotatable mirror for reflecting light emitted from the light source, wherein the light irradiation device is configured to form a light distribution pattern by linearly scanning the light divided into a plurality of segments by displacing a reflection direction of the light by rotation of the mirror,

the light distribution pattern comprises a first line and a second line,

2. The light irradiation apparatus according to claim 1,

3. The light irradiation apparatus according to claim 2,

the first reflecting surface is formed by a convex curved surface.

4. The light irradiation apparatus according to claim 2,

the second reflecting surface is formed of a concavely curved surface.

5. The light irradiation apparatus according to claim 1,

6. A light irradiation apparatus as set forth in any one of claims 1 to 5,