JP2018060720A - Headlight module and headlight device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a headlight module and a headlight device that suppress light utilization efficiency from decreasing and then form a cutoff line of different height since a conventional headlight projects an image in a light distribution pattern formed at an upper part of a light shield plate through a projection lens and the shape of a cutoff line is formed by light shielding by a shade to thereby lower light utilization efficiency because of the light shielding, and a cutoff line having, especially, a shape of a rising line increases the quantity of light to be cut off as compared with a cutoff line in a horizontal shape.SOLUTION: A headlight module (100) comprises a light source (1) and a projection optical element (8). The light source (1) includes a light emission surface (11) for emitting light. The projection optical element (8) receives light, and projects light having been changed in light distribution pattern that the light forms.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a headlamp module and a headlamp device for irradiating the front of a vehicle or the like.

  A vehicle headlamp device must satisfy the conditions of a predetermined light distribution pattern determined by road traffic rules and the like.

  As one of the road traffic rules, for example, a predetermined light distribution pattern related to an automobile low beam has a horizontally long shape with a narrow vertical direction.

  The area below the cut-off line (inside the light distribution pattern) is required to have the maximum illuminance. This region with the maximum illuminance is referred to as a “high illuminance region”. Here, the “region below the cut-off line” means an upper portion in the region of the light distribution pattern, and corresponds to a portion that irradiates far away in the headlamp device.

  In addition, as another example of road traffic rules, it must have a “rise line” that raises sidewalk illumination for pedestrian identification and sign identification. This is because the oncoming vehicle is not dazzled, and people on the sidewalk, signs, and the like are visible. Here, the “rise line” indicates a shape of a light distribution pattern in which the oncoming vehicle side of the low beam is horizontal and the sidewalk side rises obliquely with respect to the oncoming vehicle side.

  Moreover, in the light distribution pattern, it is necessary to suppress uneven light distribution. The light distribution unevenness appears as a dark line or a bright line when the headlamp device illuminates the road surface. The uneven light distribution may cause the driver to misunderstand the sense of distance. For this reason, in a headlamp apparatus, it is necessary to be the light distribution which suppressed light distribution nonuniformity.

  In order to realize such a complicated light distribution pattern, a configuration of an optical system using a combination of a reflector, a shade, and a projection lens is generally used (for example, Patent Document 1).

  In Patent Document 1, the reflector is composed of a spheroidal reflecting surface, and has a first focal point, a second focal point, and a long axis. The semiconductor light source is disposed so as to be located in the vicinity of the first focal point. The shade is arranged so that the upper edge of the shade is positioned in the vicinity of the second focal point in order to block a part of the light from the reflector and form, for example, a cut-off line that becomes a light distribution pattern suitable for passing light distribution. ing. The projection lens is held by the housing such that its focal point is located near the second focal point of the reflector.

JP 2009-199938 A (paragraphs 0024 to 0026, FIG. 1)

  However, in the configuration of Patent Document 1, the image of the light distribution pattern formed on the upper part of the shade (light shielding plate) is projected by the projection lens. The cut-off line shape is formed by shading with a shade.

  That is, in the configuration of Patent Document 1, the light use efficiency decreases due to light shielding. In particular, the cut-off line having the shape of the rising line has a larger amount of light to be blocked than the horizontal cut-off line.

  When a wide light distribution pattern is formed, the light beam is totally reflected at the peripheral portion of the projection lens according to the incident angle of the light beam from the light source. For this reason, the light which is not radiate | emitted from a projection lens increases. That is, when a wide light distribution pattern is formed, uneven light distribution occurs, and the light utilization efficiency is significantly reduced.

  The present invention has been made in view of the problems of the prior art, and an object thereof is to provide a headlamp device that can form cut-off lines having different heights while suppressing a decrease in light utilization efficiency.

  The headlamp module includes a light source including a light emitting surface that emits light, and a projection optical element that receives the light and changes and projects a light distribution pattern formed by the light.

  ADVANTAGE OF THE INVENTION According to this invention, the headlamp module or headlamp apparatus which suppresses the fall of light utilization efficiency and forms the cut-off line of different height can be provided.

1 is a configuration diagram showing a configuration of a headlamp module 100 according to Embodiment 1. FIG. 3 is a perspective view of a projection lens 8 of the headlamp module 100 according to Embodiment 1. FIG. It is a schematic diagram which shows the shape of the light source 1 of the headlamp module 100 which concerns on Embodiment 1. FIG. It is a block diagram which shows the structure of 100a, 100b of the headlamp module 100 which concerns on Embodiment 1. FIG. FIG. 6 is a diagram for explaining the behavior of light rays that pass through an optical axis change region 823 of the headlamp module 100 according to Embodiment 1. It is an example of the light distribution pattern 95 of the low beam of the headlamp device for a four-wheeled vehicle projected onto the irradiation surface. It is the figure which showed the illumination intensity distribution on the irradiation surface 9 of the headlamp module 100 which concerns on Embodiment 1 by the contour display. It is the figure which showed the illumination intensity distribution on the irradiation surface 9 of the headlamp module 100 which concerns on Embodiment 1 by the contour display. It is the figure which showed the illumination intensity distribution on the irradiation surface 9 of the headlamp module 100 which concerns on Embodiment 1 by the contour display. It is a block diagram which shows the headlamp module 101 which concerns on a comparative example. It is the figure which showed the example of the shape of the light-shielding plate 5 of the headlamp module 101 which concerns on a comparative example. It is the figure which showed the illumination intensity distribution on the irradiation surface 9 of the headlamp module 101 which concerns on a comparative example by the contour display. 2 is a schematic diagram showing a shape of a light source 1. FIG. It is the figure which showed the illumination intensity distribution on the irradiation surface 9 by the contour display. FIG. 6 is a configuration diagram showing a configuration of a headlamp module 110 according to a first modification of the first embodiment. It is the figure which showed the illumination intensity distribution on the irradiation surface 9 of the headlamp module 110 which concerns on the modification 1 of Embodiment 1 by the contour display. FIG. 6 is a configuration diagram showing a configuration of a headlamp module 120 according to a second modification of the first embodiment. FIG. 6 is a configuration diagram showing a configuration of a headlamp module 130 according to a second modification of the first embodiment. It is the figure which showed the example of the shape of the light-shielding plate 50 of the headlamp module 130 which concerns on the modification 2 of Embodiment 1. FIG. It is a block diagram which shows the structure of the headlamp module 140 which concerns on the modification 3 of Embodiment 1. FIG. It is the block diagram which showed the structure of the headlamp apparatus 10 which mounted the headlamp module 100 of Embodiment 2. FIG.

  The “headlight device” is an illuminating device that is mounted on a transport machine or the like and used to improve the visibility of the operator and the visibility from the outside. A vehicle headlamp device is also called a headlamp or a headlight.

  Further, the projection lens is used in the same meaning as the projection lens. Here, “projection” means throwing light rays. “Projection” refers to projecting an image. Here, the projection lens 8 projects a light source image or a light distribution pattern on the irradiation surface 9.

In recent years, for example, from the viewpoint of reducing environmental burdens such as suppressing carbon dioxide (CO ₂ ) emissions and fuel consumption, it is desired to save energy in vehicles. Along with this, miniaturization, weight reduction, and power saving are also demanded in vehicle headlamp devices. Therefore, it is desired to employ a semiconductor light source as a light source of a vehicle headlamp device. The semiconductor light source has higher luminous efficiency than the conventional halogen bulb (lamp light source).

  The “semiconductor light source” is, for example, a light emitting diode (LED (Light Emitting Diode)) or a laser diode (LD (Laser Diode)).

  A conventional lamp light source (tube light source) is a light source having lower directivity than a semiconductor light source. Examples of lamp light sources include incandescent light bulbs, halogen lamps, and fluorescent lamps. For this reason, the lamp light source uses a reflector (for example, a reflecting mirror) to give directivity to the emitted light. On the other hand, the semiconductor light source includes at least one light emitting surface, and light is emitted to the light emitting surface side.

  As described above, the semiconductor light source has a light emission characteristic different from that of the lamp light source. For this reason, it is desirable to use an optical system suitable for the semiconductor light source instead of a conventional optical system using a reflector (for example, a reflector).

  For example, the reflector is suitable for a point light source lamp. For this reason, when a reflector is used for a light source such as an LED, the number of light sources is not a single point but a large number, and unnecessary light increases. Then, the light that is correctly reflected by the reflector is reduced, and wasted light becomes glare light. This causes a reduction in the amount of light in the area of the light distribution pattern.

  The above-described semiconductor light source is a kind of solid light source. Examples of the solid light source include a light source that emits light by irradiating organic electroluminescence (organic EL) or a phosphor applied on a flat surface with excitation light. It is desirable to use the same optical system as the semiconductor light source for these solid light sources.

  In this way, a light source having a directivity without including a tube light source is referred to as a “solid light source”.

  “Directivity” is a property in which, when light or the like is output into space, its intensity varies depending on the direction. Here, “having directivity” means that light travels to the front surface side of the light emitting surface and light does not travel to the back surface side of the light emitting surface, as described above. That is, the divergence angle of the light emitted from the light source is 180 degrees or less.

  In the vehicle headlamp of Patent Document 1, as described above, the semiconductor light source is disposed at the first focal point of the spheroid reflector. And the light radiate | emitted from the semiconductor light source is condensed on the 2nd focus. The shade (light shielding plate) shields a part of the light. The light that is not shielded is emitted forward by the projection lens.

  Moreover, the light source shown by the following embodiment is demonstrated as a light source (solid light source) with directivity. As described above, a main example is a semiconductor light source such as a light emitting diode or a laser diode. The light source also includes an organic electroluminescence light source or a light source that emits light by irradiating excitation light onto a phosphor applied on a flat surface.

  The reason why the solid light source is used as an example in the embodiment is that, when a tube light source is used, it is difficult to meet the demand for energy saving or the miniaturization of the apparatus. However, when the demand for improving the light utilization efficiency is more important than the demand for energy saving, the light source may be a tube light source. In other words, the light source may be a tube light source when there is no demand for energy saving or a miniaturization of the apparatus.

  The present invention is applied to a low beam and a high beam of a vehicle headlamp device. Further, the present invention is applied to a low beam and a high beam of a headlight device for a motorcycle. Further, the present invention is also applied to a headlamp device for other vehicles such as three wheels or four wheels.

  However, in the following description, a case where a low beam light distribution pattern of a headlight device for an automobile is formed will be described as an example. The light distribution pattern of the low beam of the headlight device for an automobile is a cut-off line having a rising line shape. That is, the height of the cut-off line differs between the pedestrian side (own vehicle side) and the oncoming vehicle side.

  The cut-off line is a light-dark dividing line formed when the light of the headlamp is irradiated on the wall or the screen, and is a dividing line on the upper side of the light distribution pattern. That is, the “cut-off line” is a boundary line portion between a bright portion and a dark portion that can be formed in the contour portion of the light distribution pattern. The “cut-off line” is a boundary line between the bright part and the dark part of the light on the upper side of the light distribution pattern. That is, the upper side of the cutoff line (outside of the light distribution pattern) is dark, and the lower side of the cutoff line (inside of the light distribution pattern) is bright.

  The “cut-off line” is required to be clear. Here, “clear” means that no significant chromatic aberration or blurring should occur in the cut-off line. In order to realize such a clear cut-off line, a large chromatic aberration or blurring should not occur in the cut-off line. “The blur occurs in the cut-off line” means that the cut-off line becomes unclear.

  The road traffic rules require that the upper boundary of the light distribution pattern (cut-off line) be clear so as not to dazzle oncoming vehicles. That is, a clear cut-off line is required in which the upper side of the cut-off line (outside the light distribution pattern) is dark and the lower side of the cut-off line (inside the light distribution pattern) is bright.

  The cut-off line is a term used when adjusting the irradiation direction of the headlight device for passing. The headlight device for passing is also called a low beam.

  The “low beam” is a downward beam, and is used when passing the oncoming vehicle. Usually, the low beam illuminates about 40m ahead. The “vertical direction” is a direction perpendicular to the ground (road surface).

  The light distribution pattern on the wall or screen is described as the illuminance distribution. For this reason, the brightest region is called a “high illuminance region”. On the other hand, when the light distribution pattern is regarded as a light intensity distribution, the brightest region of the light distribution pattern is a “high light intensity region”. For example, a high luminous intensity region of a light distribution pattern on a conjugate plane PC described later corresponds to a high illuminance region of the light distribution pattern on the irradiation surface 9.

  In addition, as described above, as an example of other road traffic rules, for the identification of pedestrians and signs, the headlamp device must have a “rise line” that raises the sidewalk side illumination. Don't be. This is because the driver can visually recognize a person or a sign on the sidewalk side without making the oncoming vehicle dazzled. Here, the “rise line” indicates a shape of a light distribution pattern in which the oncoming vehicle side of the low beam is horizontal and the sidewalk side rises obliquely with respect to the oncoming vehicle side.

  The above-described wall or screen is described as the irradiation surface 9 in the following embodiment. The irradiation surface 9 is a virtual surface set at a predetermined position in front of the vehicle. The irradiation surface 9 is a surface parallel to the XY plane. That is, the irradiation surface 9 is a surface perpendicular to the direction in which the headlamp device irradiates light (+ Z-axis direction).

  The predetermined position in front of the vehicle is a position where the light intensity or illuminance of the headlamp device is measured. The predetermined position in front of the vehicle is defined by road traffic rules and the like. For example, in Europe, the measurement position of the luminous intensity of the automotive headlamp device defined by UNECE (United States Economic Commission for Europe) is a position 25 m from the light source. In Japan, the measurement position of luminous intensity determined by the Japanese Industrial Standards Committee (JIS) is a position 10 m from the light source.

  The shade cutoff line has the shape of a rising line. The rising line changes the height of the cut-off line between the oncoming vehicle side and the pedestrian side. The pedestrian side can be said to be the own vehicle side (own vehicle side) in comparison with the oncoming vehicle side. The cut-off line on the oncoming vehicle side is lower in height than the cut-off line on the pedestrian side (own vehicle side) in order to prevent dazzling due to the light from the headlamp. In other words, when looking at the light distribution pattern, the shade on the oncoming vehicle side blocks more light than the shade on the pedestrian side (own vehicle side). That is, when a complicated cut-off line having a different height depending on the position of the cut-off line, such as a rising line, the amount of light to be shielded is increased, so that the light use efficiency is lowered.

  The focal point of the projection lens is located on the shade. The projection lens inverts and projects the image of the light distribution pattern formed at the position of the shade forward. That is, the image of the light distribution pattern is reversed in the left-right direction and the up-down direction. In order to obtain a wide light distribution pattern, the projection lens refracts light rays greatly. That is, the projection lens has a large positive power.

  For this reason, the inclination of the surface with respect to the optical axis increases at the periphery of the exit surface of the projection lens. Then, a part of the light beam incident on the projection lens is totally reflected at the peripheral exit surface. The totally reflected light beam is not emitted forward. That is, the wider the width of the light distribution pattern, the more light that is not emitted from the projection lens. For this reason, light use efficiency falls.

  In the embodiment described below, an optical surface having a plurality of surfaces with different optical axes in the height direction is used to form cut-off lines having different heights. By using this optical surface, a decrease in light utilization efficiency is suppressed. Moreover, the example which employ | adopted the solid light source as a light source is shown.

  “Light distribution” refers to a light intensity distribution with respect to a space of a light source. That is, the spatial distribution of light emitted from the light source. “Luminance” indicates the intensity of light emitted from a light emitter, and is obtained by dividing a light beam passing through a minute solid angle in a certain direction by the minute solid angle. In other words, “luminosity” is a physical quantity that represents how much light is emitted from the light source. “Illuminance” is a physical quantity representing the brightness of light irradiated on a planar object. It is equal to the light beam irradiated per unit area.

  The “light distribution pattern” indicates the shape of the light flux and the light intensity distribution (luminous intensity distribution) caused by the direction of the light emitted from the light source. The “light distribution pattern” is also used as the meaning of the illuminance pattern on the irradiation surface 9 shown below. That is, the light irradiation shape and illuminance distribution on the irradiation surface 9 are shown. The “light distribution” is a light intensity distribution (luminance distribution) with respect to the direction of light emitted from the light source. “Light distribution” is also used as the meaning of the illuminance distribution on the irradiation surface 9 shown below.

  For this reason, in the following embodiments, for example, an image (light distribution pattern) formed on the conjugate plane PC is also described as a light intensity distribution.

  The four-wheel vehicle is, for example, a normal four-wheel vehicle. The three-wheeled vehicle is, for example, an automatic tricycle called a gyro. "Automobile tricycle called gyro" is a scooter made of three wheels with one front wheel and one rear wheel. In Japan, it corresponds to a motorbike. A rotating shaft is provided near the center of the vehicle body, and most of the vehicle body including the front wheels and the driver's seat can be tilted in the left-right direction. With this mechanism, the center of gravity can be moved inward during turning as with a motorcycle.

  Hereinafter, an example of an embodiment according to the present invention will be described with reference to the drawings, taking a vehicle headlamp device as an example. In the following description of the embodiments, description will be made using XYZ coordinates for ease of explanation.

  The left-right direction of the vehicle is the X-axis direction. The left side with respect to the front of the vehicle is the + X axis direction, and the right side with respect to the front of the vehicle is the −X axis direction. Here, “front” refers to the traveling direction of the vehicle. That is, “front” is a direction in which the headlamp device irradiates light.

  The vertical direction of the vehicle is the Y-axis direction. The upper side is the + Y axis direction, and the lower side is the -Y axis direction. The “upper side” is the sky direction, and the “lower side” is the direction of the ground (road surface, etc.). The height direction is the Y-axis direction.

  The traveling direction of the vehicle is the Z-axis direction. The traveling direction is the + Z-axis direction, and the opposite direction is the -Z-axis direction. The + Z-axis direction is called “front”, and the −Z-axis direction is called “rear”. That is, the + Z-axis direction is a direction in which the headlamp device emits light.

  As described above, in the following embodiments, the ZX plane is a plane parallel to the road surface. This is because the road surface is a “horizontal plane” in normal thinking. For this reason, the ZX plane is considered as a “horizontal plane”. A “horizontal plane” is a plane perpendicular to the direction of gravity.

  However, the road surface may be inclined with respect to the traveling direction of the vehicle. That is, uphill or downhill. In these cases, the “horizontal plane” is considered as a plane parallel to the road surface. That is, the “horizontal plane” is not a plane perpendicular to the direction of gravity.

  On the other hand, it is rare that a general road surface is inclined in the left-right direction with respect to the traveling direction of the vehicle. The “left-right direction” is the width direction of the runway. In these cases, the “horizontal plane” is considered as a plane perpendicular to the direction of gravity. For example, even if the road surface is inclined in the left-right direction and the vehicle is perpendicular to the left-right direction of the road surface, it is considered to be equivalent to a state in which the vehicle is inclined in the left-right direction with respect to the “horizontal plane”.

  In order to simplify the following description, the “horizontal plane” is described as a plane perpendicular to the direction of gravity. That is, the ZX plane will be described as a plane perpendicular to the direction of gravity.

Embodiment 1 FIG.
FIG. 1A and FIG. 1B are configuration diagrams showing the configuration of the headlamp module 100 according to the first embodiment. FIG. 1A is a view as seen from the right side (−X axis direction) with respect to the front of the vehicle. FIG. 1B is a diagram viewed from the upper side (+ Y-axis direction).

  FIG. 2 is a perspective view of the projection lens 8. FIG. 3 is a schematic diagram showing the shape of the light source 1. In FIG. 3, the light source 1 is viewed from the light emitting surface 11 side (+ Z axis side).

  FIGS. 4A and 4B are configuration diagrams showing configurations of the headlamp modules 100a and 100b according to the first embodiment. 4A and 4B are views seen from the upper side (+ Y-axis direction).

  As shown in FIG. 1, the headlamp module 100 according to Embodiment 1 includes a light source 1 and a projection lens 8.

<Light source 1>
The light source 1 includes a light emitting surface 11. The light source 1 emits light from the light emitting surface 11. For example, the light source 1 emits light for illuminating the front of the vehicle from the light emitting surface 11. Light for illuminating the front of the vehicle is also called projection light.

  The light source 1 is located on the −Z axis direction side of the projection optical element 8.

  In FIG. 1, the light source 1 emits light in the + Z-axis direction. “Exit” is to emit light in a certain direction.

  The end 111 of the light emitting surface 11 of the light source 1 has a shape including a straight line portion. The end 111 is located on the −Y axis direction side of the light emitting surface 11. Further, the straight line portion is, for example, parallel to the X-axis direction.

  In the first embodiment, for example, a case where the light emitting surface is rectangular as shown in FIG. 3 is shown. In the example of FIG. 3, the end 111 of the light emitting surface 11 is located in the −Y axis direction. The end 111 is an edge on the −Y axis direction side of the light emitting surface 11. The end 111 is a side on the −Y axis direction side of the light emitting surface 11. Further, the end 111 is, for example, parallel to the X axis.

  The type of the light source 1 is not particularly limited. However, as described above, in the following description, the light source 1 will be described as an LED (light emitting diode). Hereinafter, the light emitting diode is referred to as an LED.

An axis extending perpendicularly to the light emitting surface 11 from the center of the light emitting surface 11 of the light source 1 is defined as an optical axis Cs of the light source 1. In FIG. 3, for example, the optical axis Cs of the light source 1 is parallel to the Z axis.
<Projection lens 8>

  The projection lens 8 is a lens having positive power. The projection lens 8 deforms the image of the light emitting surface 11 of the light source 1. The projection lens 8 projects the deformed image of the light emitting surface 11 onto the irradiation surface 9 in front of the vehicle. The deformed image of the light emitting surface 11 is a light distribution pattern.

  The projection lens 8 changes the image of the light emitting surface 11 of the light source 1. The image change includes a shape change. Also, changing the image can include changing the brightness distribution. The modified image is a light distribution pattern. The projection lens 8 enlarges and projects the light distribution pattern.

  The projection lens 8 is an example of a “projection optical element”. In the embodiment, as an example, the projection optical element will be described as a projection lens 8.

  The projection lens 8 may be composed of a single lens. Further, the projection lens 8 may be configured using a plurality of lenses. However, as the number of lenses increases, the light utilization efficiency decreases. For this reason, it is desirable that the projection lens 8 be composed of one or two.

  The projection lens 8 is made of a transparent resin or the like. The material of the projection lens 8 is not limited to a transparent resin, and any material that transmits light may be used. “Translucent” is a property of transmitting light.

  The projection lens 8 has at least two optical axes. That is, the projection lens 8 has a plurality of optical axes. For example, the emission surface 82 of the projection lens 8 shown in FIG. 1 includes a first optical axis region 821, a second optical axis region 822, and an optical axis change region 823.

  The first optical axis region 821, the optical axis changing region 823, and the second optical axis region 822 are arranged side by side in the left-right direction (X-axis direction). The first optical axis region 821 is disposed on the + X axis side of the emission surface 82. The optical axis change region 823 is disposed on the −X axis side of the first optical axis region 821. The second optical axis region 822 is disposed on the −X axis side of the optical axis change region 823. The optical axis change region 823 is disposed between the first optical axis region 821 and the second optical axis region 822.

The optical axis of the first optical axis region 821 is the optical axis Cp ₁ . The optical axis of the second optical axis region 822 is an optical axis Cp _2.

The optical axis Cp ₁ and the optical axis Cp ₂ do not coincide with the optical axis Cs of the light source 1. For example, the optical axis Cp ₁ and the optical axis Cp ₂ are located on the lower side (−Y axis direction) than the optical axis Cs of the light source 1. The optical axis Cp ₂ is positioned on the lower side (-Y-axis direction) of the optical axis Cp _1. In the first embodiment, for example, the optical axis Cs, the optical axis Cp ₁ and the optical axis Cp ₂ are parallel to each other.

The position of the optical axis change region 823 in the height direction of the optical axis changes between the optical axis Cp ₁ and the optical axis Cp ₂ . The height direction is the Y-axis direction. In the case of FIG. 1, the position of the optical axis on the + X axis side is higher than the position of the optical axis on the −X axis side in the region of the optical axis changing region 823.

  For example, the projection lens 8 has different powers in the X-axis direction and the Y-axis direction. The projection lens 8 is a toroidal lens, for example. In FIG. 1, the projection lens 8 does not have power in the X-axis direction for the sake of simplicity. The projection lens 8 is, for example, a cylindrical lens.

  The toroidal lens surface is a surface having different curvatures in two orthogonal directions, such as a barrel surface or a donut surface. A lens having a toroidal lens surface is called a toroidal lens.

  The cylindrical lens surface is a surface having a curvature in one direction (first direction) and having no curvature in a direction (second direction) perpendicular to the direction (first direction). A lens having a cylindrical lens surface is called a cylindrical lens. When light is incident on the cylindrical lens, light is condensed or diverged in only one direction. When parallel light is incident on a convex cylindrical lens, the light is collected in a linear shape. This condensed line is called a focal line.

  The position of the focal point of the projection lens 8 in the Y-axis direction will be described. The positions of the focal points of the first optical axis region 821, the second optical axis region 822, and the optical axis changing region 823 in the Y-axis direction will be described.

  The position of the focal point of the first optical axis region 821 in the Y-axis direction matches, for example, the position of the end 111 of the light emitting surface 11 in the Y-axis direction. That is, the position of the focal point of the first optical axis region 821 in the Y-axis direction is, for example, the same position as the end 111 of the light emitting surface 11 in the Y-axis direction.

In FIG. 1, the focal point of the first optical axis region 821 is located on the light emitting surface 11. The focal point of the first optical axis region 821 is located on the end 111 of the light emitting surface 11. That is, the focal point of the first optical axis region 821 is at the intersection of the optical axis Cp ₁ and the end 111 of the light emitting surface 11. Therefore, a plane parallel to the XY plane including the light emitting surface 11 via the first optical axis region 821 is a position optically conjugate with the irradiation surface 9 in the Y-axis direction. The light emitting surface 11 is located on the conjugate plane PC. That is, the conjugate plane PC includes the light emitting surface 11.

  That is, in the region of the first optical axis region 821, the light emitting surface 11 is optically conjugate with the irradiation surface 9 in the Y-axis direction. In the region of the first optical axis region 821, the light emitting surface 11 is not necessarily optically conjugate with the irradiation surface 9 in the X-axis direction.

  When the first optical axis region 821 is a cylindrical lens surface, as described above, the focal point of the first optical axis region 821 is a linear focal line. As shown in FIG. 3, when the light emitting surface 11 is rectangular, the focal line of the first optical axis region 821 coincides with the end 111.

  The position of the focal point of the second optical axis region 822 in the Y-axis direction is, for example, within the range of the light emitting surface 11 in the Y-axis direction.

In FIG. 1, the focal point of the second optical axis region 822 is located below the light emitting surface 11. That is, the focal point of the second optical axis region 822 is at the intersection of the optical axis Cp ₂ and the plane including the light emitting surface 11. Therefore, a plane parallel to the XY plane including the light emitting surface 11 via the second optical axis region 822 is an optically conjugate position with the irradiation surface 9.

  That is, in the region of the second optical axis region 822, the light emitting surface 11 is optically conjugate with the irradiation surface 9 in the Y-axis direction. In the region of the second optical axis region 822, the light emitting surface 11 is not necessarily an optically conjugate position with the irradiation surface 9 in the X-axis direction.

  When the second optical axis region 822 is a cylindrical lens surface, as described above, the focal point of the second optical axis region 822 is a linear focal line.

The position of the focal point of the optical axis change region 823 in the Y axis direction is, for example, between the optical axis Cp ₁ and the optical axis Cp _{2 in} the Y axis direction.

  In the first embodiment, the focal point of the optical axis changing region 823 is located on the surface including the light emitting surface 11. Therefore, a plane parallel to the XY plane including the light emitting surface 11 via the optical axis changing region 823 is an optically conjugate position with the irradiation surface 9 in the Y-axis direction.

  That is, in the region of the optical axis changing region 823, the light emitting surface 11 is optically conjugate with the irradiation surface 9 in the Y-axis direction. In the region of the optical axis changing region 823, the light emitting surface 11 is not necessarily an optically conjugate position with the irradiation surface 9 in the X-axis direction.

  “Optically conjugate” refers to a relationship in which light emitted from one point forms an image at another point. Therefore, in the case of the projection lens 8, the light emission pattern of the light emitting surface 11 is inverted and projected onto the irradiation surface 9 in the Y-axis direction. Note that the light emission pattern of the light emitting surface 11 is not necessarily projected onto the irradiation surface 9 in the X-axis direction.

  By arranging in this way, a cut-off line having a rising line can be formed on the irradiation surface 9. The cut-off line is formed using the end 111 of the light source 1. The cut-off line on the irradiation surface 9 is formed by deforming the image of the end 111 of the light source 1.

  As shown in FIG. 3, when viewed on the XY plane, in the light emitting surface 11 of the light source 1, the end 111 is a boundary line of the light emitting surface 11. That is, the upper side (+ Y axis side) from the end 111 is a light emitting region. The lower side (−Y axis side) than the end portion 111 is a non-light emitting region.

  The projection lens 8 inverts and projects the relationship divided into the light emitting region and the non-light emitting region with the end 111 as a boundary on the irradiation surface 9. A cut-off line is formed on the irradiation surface 9 by this inverted projection. The projection lens 8 forms a rising line in this cut-off line.

<Behavior of light>
As shown in FIG. 1, the light emitted from the light source 1 reaches the incident surface 81 of the projection lens 8. The light that has reached the incident surface 81 enters the projection lens 8 from the incident surface 81. The light incident on the projection lens 8 is emitted from any one of the first optical axis region 821, the second optical axis region 822, and the optical axis change region 823. The first optical axis region 821, the second optical axis region 822, and the optical axis change region 823 are regions of the emission surface 82.

  The exit surface 82 of the projection lens 8 is, for example, a convex refracting surface having a curvature only in the Y-axis direction. That is, the projection lens 8 is a cylindrical lens.

  Here, the curvature of the projection lens 8 in the Y-axis direction contributes to the “light distribution height” in the direction perpendicular to the road surface. The curvature of the projection lens 8 in the X-axis direction contributes to the “light distribution width” in the horizontal direction with respect to the road surface.

  The “light distribution width” is the length of the light distribution pattern projected on the irradiation surface 9 in the X-axis direction. The “light distribution height” is the length in the Y-axis direction of the light distribution pattern projected onto the irradiation surface 9.

  In the above description, the exit surface 82 of the projection lens 8 has been described as a cylindrical lens having a curvature only in the Y-axis direction. However, the “light distribution width” can be adjusted by adjusting the X-axis power of the exit surface 82. That is, the X-axis direction and the Y-axis direction have different curvatures.

  Examples of the lens surface having different curvatures in the X-axis direction and the Y-axis direction include a toroidal lens surface.

<Behavior of rays on the ZX plane>
First, light that passes through the first optical axis region 821 or the second optical axis region 822 will be described.

  For example, as shown in FIG. 1B, when viewed in the ZX plane, the first optical axis region 821 and the second optical axis region 822 have a planar shape. That is, the first optical axis region 821 and the second optical axis region 822 do not have power in the horizontal direction (X-axis direction).

  Here, for example, “view in the ZX plane” means to view from the Y-axis direction. That is, it is projected on the ZX plane and viewed.

In the case of FIG. 1B, when viewed in the ZX plane, the position of the optical axis Cp _{1 and} the position of the optical axis Cp ₂ are the same as the position of the optical axis Cs.

  In FIG. 1B, rays R11 and R12 are shown as representative rays that pass through the first optical axis region 821. Rays R11 and R12 are drawn with solid lines.

On Z-X plane, the angle _{a 3} of rays R11, R12 with respect to the optical axis Cp ₁ when emitted from the first optical axis region 821, the optical axis Cp ₁ when incident on the incident surface 81 of the projection lens 8 is the same as the angle _{a 1} of the light beam R11, R12 for.

  In FIG. 1B, on the ZX plane, the incident angle of the light beam R11 when entering the incident surface 81 is the same as the incident angle of the light beam R12. In addition, on the ZX plane, the emission angle of the light ray R11 when emitted from the first optical axis region 821 is the same as the emission angle of the light ray R12. In addition, on the ZX plane, the incident angles of the light rays R11 and R12 when entering the incident surface 81 are the same as the emission angles of the light rays R11 and R12 when emitted from the first optical axis region 821.

Also, light rays R11 transmitted through the first optical axis region 821, R12 reaches the position of the + X-axis direction of the optical axis Cp ₁ on the irradiated surface 9. That is, the light transmitted through the first optical axis region 821 contributes to the “light distribution width” in the + X-axis direction.

  On the other hand, in FIG. 1B, light rays R21 and R22 are shown as representative light rays that pass through the second optical axis region 822. Rays R21 and R22 are drawn with broken lines.

On Z-X plane, the angle _{a 4} of the ray R21, R22 with respect to the optical axis Cp ₂ when emitted from the second optical axis region 822, the optical axis Cp ₂ when incident on the incident surface 81 of the projection lens 8 is the same as the angle _{a 2} of the ray R21, R22 for.

  In FIG. 1B, on the ZX plane, the incident angle of the light ray R21 when entering the incident surface 81 is the same as the incident angle of the light ray R22. In addition, on the ZX plane, the emission angle of the light ray R21 when emitted from the second optical axis region 822 is the same as the emission angle of the light ray R22. In addition, on the ZX plane, the incident angles of the light beams R21 and R22 when entering the incident surface 81 are the same as the exit angles of the light beams R21 and R22 emitted from the second optical axis region 822.

Also, light rays R21, R22 transmitted through the second optical axis region 822 reaches the position of the -X-axis direction from the optical axis Cp ₂ on the irradiated surface 9. That is, the light transmitted through the second optical axis region 822 contributes to the “light distribution width” in the −X axis direction.

  That is, in the case of FIG. 1B, the width of the light distribution pattern formed by the light transmitted through the first optical axis region 821 or the second optical axis region 822 is the incident angle of the light beam when entering the projection lens 8. Determined by.

  Next, description will be made with reference to FIGS. 4 (A) and 4 (B). 4A and 4B are views as seen from the upper side (+ Y-axis direction).

For example, as shown in FIG. 4A, the first optical axis region 821 and the second optical axis region 822 can be formed in a convex shape on the ZX plane. The optical axis of the first optical axis region 821 is the optical axis Cp ₁ . The optical axis of the second optical axis region 822 is an optical axis Cp _2. That is, the first optical axis region 821 and the second optical axis region 822 each have a positive power.

In this case, the light emitted from the first optical axis region 821 or the second optical axis region 822 is condensed and applied to the irradiation surface 9. That is, in the ZX plane, the first optical axis region 821 or the second optical axis region 822 is compared with the light angles a ₁ and a ₂ with respect to the optical axes Cp ₁ and Cp ₂ when entering the projection lens 8a. The angles a ₅ and a ₆ of the light rays with respect to the optical axes Cp ₁ and Cp ₂ when transmitted are reduced. Therefore, light transmitted through the first optical axis region 821 or the second optical axis region 822 is formed on the irradiation surface 9 as compared with the case where the first optical axis region 821 and the second optical axis region 822 do not have power. The width of the light distribution becomes narrower.

For example, as shown in FIG. 4B, the first optical axis region 821 and the second optical axis region 822 can be formed in a concave shape on the ZX plane. The optical axis of the first optical axis region 821 is the optical axis Cp ₁ . The optical axis of the second optical axis region 822 is an optical axis Cp _2. That is, the first optical axis region 821 and the second optical axis region 822 each have negative power.

In this case, the light emitted from the first optical axis region 821 or the second optical axis region 822 is diverged and applied to the irradiation surface 9. That is, on the ZX plane, the first optical axis region 821 or the second optical axis region 822 is compared with the light angles a ₁ and a ₂ with respect to the optical axes Cp ₁ and Cp ₂ when entering the projection lens 8b. The angles a ₇ and a ₈ of light rays with respect to the optical axes Cp ₁ and Cp ₂ when passing through the light beam are increased. Therefore, light transmitted through the first optical axis region 821 or the second optical axis region 822 is generated on the irradiation surface 9 as compared with the case where the first optical axis region 821 and the second optical axis region 822 do not have power. The range of light distribution becomes wider.

  The width of the light distribution pattern formed by the light transmitted through the first optical axis region 821 varies depending on the curvature of the first optical axis region 821. Further, the width of the light distribution pattern formed by the light transmitted through the second optical axis region 822 varies depending on the curvature of the second optical axis region 822.

As described in FIG. 4, in the first embodiment, in the X-axis direction on Z-X plane, and the optical axis Cp ₁ and the optical axis Cp _2, it is made to coincide with the optical axis Cs. However, it is not limited to this. Each optical axis Cs, Cp ₁ , Cp ₂ may be shifted in the X-axis direction. That is, the positions of the optical axes Cs, Cp ₁ and Cp _{2 in} the X-axis direction may be different from each other.

  Next, light passing through the optical axis change region 823 will be described.

  For example, as shown in FIG. 1B, when viewed in plan on the ZX plane, the optical axis change region 823 has a linear shape at the position of the surface vertex of the optical axis change region 823. That is, the optical axis change region 823 does not have power in the horizontal direction at the position of the surface vertex.

  However, as shown in FIGS. 1A and 2, at the same position in the Y-axis direction, the position of the first optical axis region 821 in the Z-axis direction is the same as the position of the second optical axis region 822 in the Z-axis direction. It is in a different position.

  The optical axis change region 823 is a region connecting the first optical axis region 821 and the second optical axis region 822. For this reason, in the X-axis direction, the optical axis change region 823 is inclined toward the portion connected to the first optical axis region 821. Further, in the X-axis direction, the optical axis change region 823 is inclined toward a portion connected to the second optical axis region 822.

  In FIG. 1B, light rays R31, R32, and R33 are shown as representative light rays that pass through the optical axis changing region 823. Rays R31, R32, and R33 are drawn with a two-dot chain line.

  A light ray R <b> 31 indicates a light ray that passes through the position of the surface vertex in the Y-axis direction of the optical axis change region 823. At the position of the surface vertex, the optical axis change region 823 has no inclination in the X-axis direction.

Therefore, on the Z-X plane, the angle of the light beam R31 with respect to the optical axis Cp ₃ when emitted from the optical axis changing region 823, a light flux to the optical axis Cp ₃ when incident on the incident surface 81 of the projection lens 8 It is the same as the angle of R31.

  In FIG. 1B, the light ray R31 is emitted from the optical axis changing region 823 at the same emission angle as the incident angle when entering the incident surface 82.

Regarding the light rays R31, R32, and R33, the angles a ₁ , a ₂ , a ₃ , a ₄ , a ₅ , and a ₆ are not shown in the drawing as the light rays R11, R12, R21, and R22. However, the relationship between the ray R31 and the angle is the same as in the case of the rays R11, R12, R21, and R22.

  A light ray R <b> 32 indicates a light ray that passes through the end portion in the + Y-axis direction of the optical axis change region 823. At the end in the + Y-axis direction, the first optical axis region 821 protrudes in the + Z-axis direction from the second optical axis region 822. The optical axis change region 823 is formed with an inclined surface so as to connect the first optical axis region 821 and the second optical axis region 822.

Therefore, light rays R32 is on the Z-X plane, with respect to the angle with respect to the optical axis Cp ₃ when incident on the incident surface 81 of the projection lens 8, the optical axis Cp ₃ when emitted from the optical axis changed region 823 Is larger in the + X-axis direction.

  A light ray R33 indicates a light ray that passes through the end of the optical axis change region 823 in the -Y-axis direction. At the end in the −Y axis direction, the second optical axis region 822 protrudes in the + Z axis direction from the first optical axis region 821. The optical axis change region 823 is formed with an inclined surface so as to connect the first optical axis region 821 and the second optical axis region 822.

Therefore, light rays R33 is on the Z-X plane, with respect to the angle with respect to the optical axis Cp ₃ when incident on the incident surface 81 of the projection lens 8, the optical axis Cp ₃ when emitted from the optical axis changed region 823 Is larger in the −X-axis direction.

<Behavior of rays on the ZY plane>
As shown in FIG. 1A, the exit surface 82 of the projection lens 8 has positive power. Further, the position of the focal point of the emission surface 82 of the projection lens 8 in the Z-axis direction coincides with the position of the light emitting surface 11 in the Z-axis direction. That is, the focal point of the emission surface 82 of the projection lens 8 is located on the surface including the light emitting surface 11.

  In FIG. 1, the focal point of the emission surface 82 of the projection lens 8 is located on the light emitting surface 11. That is, the light emitting surface 11 is optically conjugate with the irradiation surface 9 in the Y-axis direction.

  First, light transmitted through the first optical axis region 821 and the second optical axis region 822 will be described.

  On the ZY plane, the light incident from the incident surface 81 of the projection lens 8 and emitted from the first optical axis region 821 or the second optical axis region 822 causes the image of the light emitting surface 11 to be incident on the irradiation surface 9. Form an image.

  The end 111 of the light emitting surface 11 includes a linear shape parallel to the X axis. In FIG. 3, the end 111 of the light emitting surface 11 has a linear shape parallel to the X axis. For this reason, of the light emitted from the end 111 of the light emitting surface 11, the light transmitted through the first optical axis region 821 or the second optical axis region 822 has a linear shape parallel to the X axis of the light distribution pattern, Projected onto the irradiation surface 9.

In the example of FIG. 1A, the optical axis Cp ₁ of the first optical axis region 821 is at the same height as the end 111 of the light emitting surface 11 in the Y-axis direction. For example, the optical axis Cp ₁ of the first optical axis region 821 passes through the end 111 of the light emitting surface 11. The optical axis Cp ₁ of the first optical axis region 821 intersects the end 111 of the light emitting surface 11.

  The light rays R11 and R12 are emitted from the end 111 and pass through the first optical axis region 821. In FIG. 1, the light rays R11 and R12 are drawn with solid lines.

Rays R11, R12 are, on the irradiation surface 9, to reach the optical axis Cp _1. Accordingly, as shown in FIG. 1A, the light rays R <b> 11 and R <b> 12 reach the same height as the end portion 111 on the irradiation surface 9.

On the other hand, in the Y-axis direction, the optical axis Cp ₂ of the second optical axis region 822 is at a position lower than the optical axis Cp _{1 of} the first optical axis region 821. For example, the optical axis Cp ₂ of the second optical axis region 822 passes through a position lower than the end 111 of the light emitting surface 11. In the first embodiment, the “low position” is the −Y axis direction.

  The light rays R21 and R22 are emitted from the end portion 111 and pass through the second optical axis region 822. In FIG. 1, the light rays R21 and R22 are drawn with broken lines. For this reason, in the second optical axis region 822, the light rays R21 and R22 are refracted downward (−Y-axis direction) with respect to the light rays R11 and R12.

Rays R21, R22 are, on the irradiation surface 9, to reach the optical axis Cp _2. Accordingly, as shown in FIG. 1A, the light beams R <b> 21 and R <b> 22 reach a position lower than the end portion 111 on the irradiation surface 9. In the irradiation surface 9, the optical axis Cp ₂ is positioned in the -Y axis direction from the optical axis Cp _1.

  That is, the image on the irradiation surface 9 formed by the light transmitted through the second optical axis region 822 is projected to a position lower than the image on the irradiation surface 9 formed by the light transmitted through the first optical axis region 821. Is done.

  That is, each of the first optical axis region 821 and the second optical axis region 822 of the projection lens 8 projects light distribution patterns having different heights on the irradiation surface 9.

<Behavior of light passing through optical axis changing region 823>
Next, light that passes through the optical axis changing region 823 will be described.

  FIG. 5 is a diagram for explaining the behavior of light rays that pass through the optical axis changing region 823. FIG. 5A is a diagram illustrating the behavior of light rays on the YZ plane. FIG. 5B is a diagram illustrating the behavior of light rays on the ZX plane.

  FIG. 5B shows the behavior of the light rays R311 and R312 in the ZX plane. In FIG. 5B, light rays R311 and R312 are emitted from the same position in the X-axis direction of the light source 11 when viewed on the XZ plane. Light rays R311 and R312 are transmitted through the optical axis change region 823.

  R311 transmits the position close to the first optical axis region 821 of the optical axis changing region 823. In addition, R312 transmits a position close to the second optical axis region 822 of the optical axis change region 823. In the optical axis change region 823, the light ray R311 transmits in the + X-axis direction more than the light ray R312.

  That is, on the ZX plane, the inclination of the light ray R311 with respect to the optical axis Cs is different from the inclination of the light ray R312 with respect to the optical axis Cs.

  Regarding the light rays R311, R312 as well as the light rays R31, R32, R33, the angle is omitted from the drawing. However, the relationship between the light rays RR311, R312 and the angle is the same as that of the light rays R11, R12, R21, R22.

  FIG. 5A shows the behavior of light rays R311 and R312 in the YZ plane. In FIG. 5A, light rays R 311 and R 312 are emitted from the end 111 of the light emitting surface 11. That is, the light ray R 311 and the light ray R 312 are emitted from the same position of the end portion 111 of the light emitting surface 11.

  As shown in FIG. 5A, the light ray R311 and the light ray R322 are incident on the projection lens 8 at the same angle on the YZ plane. However, when passing through the optical axis changing region 823, the light ray R312 is refracted and emitted in the −Y-axis direction more than the light ray R311. This is because, in the optical axis change region 823, the light ray R312 passes through the second optical axis region 822 side with respect to the light ray R312.

  The light ray R312 transmits on the −X axis side from the light ray R311. The light ray R312 is refracted in the −Y-axis direction with respect to the light ray R311. That is, in the optical axis changing region 823, the light beam that passes through the −X axis side is refracted in the −Y axis direction more than the light beam that passes through the + X axis side.

That is, the optical axis change region 823, the height of the optical axis changes between the optical axis Cp ₁ and the optical axis Cp _2. Accordingly, in the optical axis change region 823, the position of the light distribution pattern on the irradiation surface 9 in the Y axis direction changes corresponding to the position in the X axis direction that passes through the optical axis change region 823. The height of the image formed on the irradiation surface 9 by the light beam transmitted through the optical axis changing region 823 is higher in the + X axis direction than in the −X axis side.

  That is, the image of the end portion 111 of the light emitting surface 11 becomes an inclined linear shape on the irradiation surface 9 by the light transmitted through the optical axis changing region 823. On the irradiation surface 9, in the Y-axis direction, the position on the + X-axis side of this linear shape is higher than the position on the -X-axis side.

<Light distribution pattern>
A low beam light distribution pattern of a headlight device for an automobile will be described.

  FIG. 6 is an example of a low beam light distribution pattern 95 of the headlight device 10 for an automobile that is projected onto the irradiation surface 9. As described above, the low beam light distribution pattern 95 of the headlight device 10 for an automobile (for automobiles) has the cutoff line 94 including the shape of the rising line 93.

  In the example of FIG. 6, the shape of the upper end of the light distribution pattern 95 includes horizontal lines 91 and 92 and a rising line 93. The horizontal lines 91 and 92 are two horizontal lines having different heights. The rising line 93 is an obliquely inclined line.

  That is, the cut-off line 94 of the light distribution pattern 95 in FIG. 6 includes horizontal lines 91 and 92 and a rising line 93. The horizontal line 91 on the left side (+ X axis direction side) is higher than the horizontal line 92 on the right side (−X axis direction). For this reason, the end of the rising line 93 on the + X axis side is higher than the end of the rising line 93 on the −X axis side.

  In the example of FIG. 6, the horizontal line 91 side is the pedestrian side (own vehicle side), and the horizontal line 92 side is the oncoming vehicle side. The case where the vehicle travels in the left lane is described. When the vehicle travels in the right lane, the left-right direction of the light distribution pattern 95 shown in FIG. 6 is reversed.

  The headlamp module 100 according to the first embodiment forms a light distribution pattern 95 by deforming the shape of the light emitting surface 11 of the light emitting surface 11 of the light source 1 by the projection lens 8. The headlamp module 100 projects a light distribution pattern 95 on the irradiation surface 9. That is, the headlamp module 100 realizes the low beam light distribution pattern 95 of the headlamp device 10 with one module. In the headlamp module 100, the light source 1 and the projection lens 8 realize a low beam light distribution pattern 95 of the headlamp device 10.

  7, 8 and 9 are diagrams showing the illuminance distribution on the irradiation surface 9 of the headlamp module 100 according to Embodiment 1 in a contour display.

  “Contour display” is to display a contour map. A “contour map” is a diagram in which dots having the same value are connected by a line.

  FIG. 7 is a diagram showing an illuminance distribution when the projection lens 8 shown in FIG. 1 is used. That is, the position of the surface vertex of the first optical axis region 821 of the emission surface 82 of the projection lens 8 is on the end 111 of the light emitting surface 11 in the Y-axis direction. The exit surface 82 of the projection lens 8 has no curvature in the X-axis direction. That is, the emission surface 82 is a cylindrical lens.

  FIG. 8 shows an illuminance distribution when the projection lens 8a shown in FIG. That is, in the Y-axis direction, the position of the surface vertex of the first optical axis region 821 of the emission surface 82 of the projection lens 8 a is on the end 111 of the light emitting surface 11. The exit surface 82 of the projection lens 8a has positive power in the X-axis direction.

  FIG. 9 shows an illuminance distribution when the projection lens 8b shown in FIG. 4B is used. That is, in the Y-axis direction, the position of the surface vertex of the first optical axis region 821 of the emission surface 82 of the projection lens 8 b is on the end 111 of the light emitting surface 11. The exit surface 82 of the projection lens 8b has a negative power in the X-axis direction.

  These illuminance distributions are illuminance distributions projected on the irradiation surface 9 25 m ahead (+ Z-axis direction) from the vehicle. These illuminance distributions are obtained by simulation.

  As can be seen from FIG. 7, the cut-off line 94 of the light distribution pattern 95 includes horizontal lines 91 and 92 and a rising line 93. The horizontal lines 91 and 92 are two horizontal lines having different heights. The rising line 93 is an obliquely inclined line.

  As can be seen from FIG. 8, the cut-off line 94 of the light distribution pattern 95 a includes horizontal lines 91 and 92 and a rising line 93. The horizontal lines 91 and 92 are two horizontal lines having different heights. The rising line 93 is an obliquely inclined line. Further, the light distribution width of the light distribution pattern 95a shown in FIG. 8 is narrower than the light distribution width of the light distribution pattern 95 shown in FIG.

  As can be seen from FIG. 9, the cut-off line 94 of the light distribution pattern 95 b includes horizontal lines 91 and 92 and a rising line 93. The horizontal lines 91 and 92 are two horizontal lines having different heights. The rising line 93 is an obliquely inclined line. Further, the light distribution width of the light distribution pattern 95b shown in FIG. 9 is wider than the light distribution width of the light distribution pattern 95 shown in FIG.

  That is, the headlamp modules 100, 100a, and 100b according to Embodiment 1 can form a light distribution pattern required for a four-wheeled vehicle. In addition, the width of the light distribution pattern can be changed by changing the curvature of the projection lens 8 in the X-axis direction.

That is, the headlamp modules 100, 100a, 100b do not require a light shielding plate in order to form the light distribution patterns 95, 95a, 95b. Further, the headlamp modules 100, 100a, 100b do not require a complicated optical system configuration in order to form the light distribution patterns 95, 95a, 95b. That is, the headlamp modules 100, 100a, and 100b can realize a headlamp device that has a small and simple configuration and improved light utilization efficiency.
<Comparative example>
Below, the comparative example for verifying the effect of the headlamp module 100 which concerns on Embodiment 1 is demonstrated. In this comparative example, the light-shielding plate 5 is added to the constituent elements of the headlamp module 100 according to the first embodiment.

  FIG. 10 is a configuration diagram showing a headlamp module 101 according to a comparative example.

  In the headlamp module 100, the focal point of the projection lens 8 is located on the surface including the light emitting surface 11. In the projection lens 8, the power in the X-axis direction is different from the power in the Y-axis direction. Further, the projection lens 8 includes a first optical axis region 821, a second optical axis region 822, and an optical axis change region 823.

  On the other hand, in the headlamp module 101, the focal point of the projection lens 8 c is located on the surface including the light shielding plate 5. That is, the focal position of the projection lens 8 c matches the position of the light shielding plate 5 in the Z-axis direction. Further, the projection lens 8c does not include the first optical axis region 821, the second optical axis region 822, and the third optical axis region 824. The projection lens 8c has the same power in the X-axis direction and power in the Y-axis direction.

  That is, the light shielding plate 5 is in an optically conjugate position with the irradiation surface 9. The irradiation surface 9 is considered to be arranged at a position at infinity with respect to the headlamp module 101. For this reason, the conjugate point is the focal point on the front side of the projection lens 8c.

  The light shielding plate 5 is disposed at the focal position on the front side of the projection lens 8c. That is, the conjugate plane PC is a plane perpendicular to the optical axis Cp of the projection lens 8c. The conjugate plane PC is at the focal position on the front side of the projection lens 8c.

  The front focal point is the focal point on the side where light enters. In the first embodiment, light is incident on the projection lenses 8, 8a, 8b, and 8c from the −Z axis direction side. That is, the focal point on the front side is the focal point on the −Z-axis side of the projection lenses 8, 8 a, 8 b, and 8 c.

  FIG. 11 is a diagram illustrating an example of the shape of the light shielding plate 5 of the headlamp module 101 according to the comparative example. The light shielding plate 5 includes sides 51, 52 and 53. The light shielding plate 5 shields light from the cut-off line shape 54 by the sides 51, 52 and 53.

  Sides 51, 52, and 53 are sides on the + Y-axis side of the light shielding plate 5. The side 51 is located on the −X axis side of the light shielding plate 5. The side 52 is located on the + X axis side of the light shielding plate 5. The side 53 is located between the side 51 and the side 52.

  The side 51 is at a lower position than the side 52. That is, the side 51 is located in the −Y axis direction with respect to the side 52. The side 53 connects the end of the side 51 on the + X-axis side and the end of the side 52 on the −X-axis side. Therefore, the side 53 is inclined clockwise with respect to the X axis.

  The light shielding plate 5 is in an optically conjugate position with the irradiation surface 9. For this reason, the light distribution pattern at the position of the light shielding plate 5 (conjugate surface PC) is similar to the light distribution pattern on the irradiation surface 9.

  The light distribution pattern at the position of the light shielding plate 5 is projected on the irradiation surface 9 with the vertical direction and the horizontal direction reversed. For this reason, the horizontal line 91 shown in FIG. 6 corresponds to the side 51. The horizontal line 92 corresponds to the side 52. The rising line 93 corresponds to the side 53. The light distribution pattern is formed by light that passes through the + Y-axis side from the cut-off line shape 54.

  FIG. 12 is a diagram showing the illuminance distribution on the irradiation surface 9 of the headlamp module 101 according to the comparative example by contour display. The simulation conditions are the same as those in FIGS.

  In FIG. 12, the light distribution pattern 95 c formed on the + Y axis side of the light shielding plate 5 is projected on the irradiation surface 9. The side 51 of the light shielding plate 5 corresponds to the horizontal line 91 of the light distribution pattern 95 c on the irradiation surface 9. The side 52 of the light shielding plate 5 corresponds to the horizontal line 92 of the light distribution pattern 95 c on the irradiation surface 9. The side 53 of the light shielding plate 5 corresponds to the rising line 93 of the light distribution pattern 95 c on the irradiation surface 9.

  The spread in the horizontal direction (X-axis direction) of the light distribution pattern 95c shown in FIG. 12 is small. This is because the light emitting surface 11 of the light source 1 is square as shown in FIG.

  The projection lens 8c projects a light distribution pattern on the conjugate plane PC. The light distribution pattern on the conjugate plane PC is formed by shielding the light from the light source 1 with the light shielding plate 5. That is, the projection lens 8 c projects a light distribution pattern similar to the light distribution pattern on the conjugate plane PC onto the irradiation surface 9.

  Therefore, the aspect ratio of the light emitting surface 11 of the light source 1 is reflected in the light distribution pattern on the irradiation surface 9. The aspect ratio is the ratio of the long side to the short side of the rectangular shape. Here, it is the ratio between the length of the side of the light emitting surface 11 in the X-axis direction and the length of the side in the Y-axis direction.

  FIG. 13 is a schematic diagram showing the shape of the light source 1. In FIG. 13, the light source 1 is viewed from the light emitting surface 11 side (+ Z axis side).

  For example, a simulation is performed for the case where the LED shown in FIG. 13 is adopted as the light source 1 of the comparative example. The aspect ratio of the light emitting surface 11 shown in FIG. 13 is, for example, 1 to 3 (1: 3). The length of the side in the Y-axis direction is 1, and the length of the side in the X-axis direction is 3.

  FIG. 14 is a diagram showing a simulation result in a contour display when the light source 1 shown in FIG. 13 is adopted. FIG. 14 is a diagram showing the illuminance distribution on the irradiation surface 9 of the headlamp module 101 according to the comparative example in a contour display.

  The width of the light distribution pattern 95d shown in FIG. 14 is wider than the width of the light distribution pattern 95c shown in FIG. However, a wide light distribution pattern is not realized like the light distribution patterns 95, 95a, and 95b shown in FIG. 7, FIG. 8, or FIG. That is, in the comparative example, in order to change the width of the light distribution pattern, it is necessary to change the aspect ratio of the light emitting surface 11 of the light source 1.

  If the aspect ratio of the light emitting surface 11 of the light source 1 is changed to make the light source 1 larger, the optical system becomes larger. Moreover, since light is shielded by the light shielding plate 5 to form a light distribution pattern, the light use efficiency is lowered.

Further, in the headlamp module 100 according to Embodiment 1, for example, as shown in FIG. 1B, when viewed on the ZX plane, the angle a when the light incident on the projection lens 8 is incident is a. ₁ and a ₂ and the angles a ₃ and a ₄ when exiting are the same. The angles a ₁ and a _{2 at} the time of incidence are angles of light rays at the time of incidence with respect to the optical axes Cp ₁ and Cp ₂ . The angles a ₃ and a _{4 at} the time of emission are angles of light rays at the time of emission with respect to the optical axes Cp ₁ and Cp ₂ . In FIG. 1, the optical axes Cp ₁ and Cp ₂ coincide with the optical axis Cp.

In other words, the width of the light distribution pattern 95 is determined by the angles a ₁ and a ₂ of the light rays when entering the projection lens 8. Accordingly, the width of the light distribution pattern 95 can be easily increased.

Further, the angles a ₁ and a ₂ at the time of incidence and the angles a ₃ and a _{4 at} the time of emission do not change. For this reason, the problem that total reflection occurs on the emission surface 82 does not occur. When total reflection occurs at the emission surface 82, light is not emitted forward. That is, the light use efficiency decreases.

  On the other hand, in the comparative example, as shown in FIG. 10B, when viewed on the ZX plane, the traveling direction of the light incident on the projection lens 8c is changed by refraction. That is, the angle with respect to the optical axis Cp at the time of emission changes with respect to the angle with respect to the optical axis Cp at the time of incidence.

  Here, the light shielding plate 5 and the irradiation surface 9 are optically conjugate. The light distribution pattern formed on the light shielding plate 5 (on the conjugate plane PC) is inverted and projected onto the irradiation surface 9.

  Accordingly, the light passing through the point P on the light shielding plate 5 in FIG. 10B is imaged at the point Q on the irradiation surface 9. The point P is a reaching point on the conjugate plane PC of the light beam that is emitted from the end portion of the light emitting surface 11 in the + X-axis direction and reaches the conjugate plane PC perpendicularly. Light rays R41 and R42 passing through the point P are refracted by the projection lens 8 and form an image at a point Q on the irradiation surface 9.

  However, the light ray R43 is totally reflected by the exit surface of the projection lens 8 and is not emitted forward (+ Z-axis direction). That is, the ray R43 does not reach the point Q. Therefore, the light ray R43 becomes lost light. That is, the light use efficiency is reduced. The light ray R43 is a light ray that passes through the point P. The light ray R43 is a light ray having a larger angle when entering the projection lens 8c than the light rays R41 and R42.

  In the headlamp module 100 according to the first embodiment, light beams having large angles a1 and a2 incident on the projection lens 8 are emitted forward (+ Z-axis direction) without being totally reflected within the projection lens 8. For this reason, light rays having large angles a 1 and a 2 incident on the projecting lens 8 contribute to the formation of the light distribution pattern 95.

  On the other hand, in Comparative Example 1, since the light is totally reflected in the projection lens 8, light that is not emitted forward (+ Z axis direction) of the projection lens 8 is generated. In addition, the light utilization efficiency is reduced. This is because the light shielding plate 5 and the irradiation surface 9 are in an optically conjugate relationship in the X-axis direction.

  Therefore, the headlamp module 100 according to the first embodiment can realize a headlamp device that has a simple configuration and suppresses a decrease in light use efficiency as compared with the conventional method as in the comparative example. .

  Some vehicles include a plurality of headlamp modules. Then, the light distribution patterns of the modules are added together to form one light distribution pattern. Even in such a case, the headlamp module 100 according to Embodiment 1 can be easily applied.

  By changing the first optical axis region 821 and the second optical axis region 822 of the exit surface 82 of the projection lens 8, the headlamp modules 100, 100a, 100b can be cut off lines (horizontal lines 91, 91) having different heights. 92) can be formed. Further, by providing the optical axis changing region 823, the headlamp modules 100, 100a, and 100b can form the rising line 93.

  Further, the headlamp modules 100, 100 a, and 100 b change the width and height of the light distribution pattern 95 by changing the curved shape in the X-axis direction and the curved shape in the Y-axis direction of the projection lens 8. Can do. The headlamp modules 100, 100 a, 100 b can change the light distribution of the light distribution pattern 95.

  The headlamp modules 100, 100a, 100b do not require the light shielding plate 5. Therefore, the number of parts can be reduced. And assemblability is improved. Further, the manufacturing cost is reduced.

Further, the function of changing the shape of the light distribution pattern 95 and the function of changing the light distribution need only be exhibited by the entire headlamp module 100, 100a, 100b. The headlamp module 100 includes a projection lens 8 as an optical component. That is, these functions can be distributed to any one of the incident surface 81 and the exit surface 82 of the projection lens 8 constituting the headlamp module 100. These functions can be given to one surface or all surfaces of the projection lens 8.
<Modification 1>
In the headlamp module 100, the case where there is one optical axis change region 823 has been described. However, a plurality of optical axis changing regions 823 can be provided.

  FIGS. 15A and 15B are configuration diagrams showing the configuration of the headlamp module 110 according to the first modification of the first embodiment.

  For example, in FIG. 15, the projection lens 8 d includes a first optical axis region 821, a second optical axis region 822, a third optical axis region 824, an optical axis change region 823, and an optical axis change region 825. As in FIG. 1, the light emitting surface 11 is located on the conjugate plane PC. That is, the conjugate plane PC includes the light emitting surface 11.

  The first optical axis region 821 is formed on the + X axis side of the emission surface 82. The optical axis change region 823 is formed on the −X axis side of the first optical axis region 821. The second optical axis region 822 is formed on the −X axis side of the optical axis change region 823. The optical axis change region 825 is formed on the −X axis side of the second optical axis region 822. The third optical axis region 824 is formed on the −X axis side of the optical axis change region 825.

  In the X-axis direction, the optical axis change region 823 is formed between the first optical axis region 821 and the second optical axis region 822. The optical axis change region 823 is a region connecting the first optical axis region 821 and the second optical axis region 822. In the X-axis direction, the optical axis change region 825 is formed between the second optical axis region 822 and the third optical axis region 824. The optical axis change region 825 is a region connecting the second optical axis region 822 and the third optical axis region 824.

The optical axis of the first optical axis region 821 is the optical axis Cp ₁ . The optical axis of the second optical axis region 822 is an optical axis Cp _2. The optical axis of the third optical axis region 824 is an optical axis Cp _3.

In the example of FIG. 15, the optical axis _{Cp 1,} Cp 2, the height of the _{Cp 3 HCp 1, HCp 2,} HCp 3 are in a relation of the formula 1. Incidentally, the larger height _{HCp 1, HCp 2, HCp 3} have shown that it is located on the + Y-axis side.
HCp ₁ > HCp ₂ (1a)
HCp ₃ > HCp ₂ (1b)
HCp ₁ > HCp ₃ (1c)

  FIG. 16 is an example of a light distribution pattern of the headlamp module 110 shown in FIG. 15 projected on the irradiation surface 9.

  As can be seen from FIG. 16, the cut-off line 94 of the light distribution pattern 95e includes horizontal lines 91, 92, 96 and rising lines 93, 97.

  The horizontal lines 91, 92, and 96 are three horizontal lines each having a different height.

  The rising line 93 is a line inclined obliquely upward to the left. That is, the height of the left end (+ X axis side) of the rising line 93 is higher than the height of the right end (−X axis side) of the rising line 93. Here, “the height is high” means that it is on the + Y axis side.

  The rising line 97 is a line inclined obliquely upward to the right. That is, the height of the left end (+ X axis side) of the rising line 97 is lower than the height of the right end (−X axis side) of the rising line 97.

Further, the relationship between the heights of the horizontal lines shown in FIG.
Horizontal line 91 height> Horizontal line 92 height (2a)
Horizontal line 96 height> Horizontal line 92 height (2b)
Horizontal line 91 height> Horizontal line 96 height (2c)

  The higher the position of the cut-off line 94, the better the visibility in the distance. That is, in the light distribution pattern 95e in FIG. 16, for example, compared to the light distribution pattern 95 in FIG. 7, far visibility on the right side (−X axis side) of the road can be improved. Therefore, the driver can easily detect a pedestrian or obstacle on the right shoulder of the road. And the light distribution pattern 95e can contribute to the safety | security of night driving | running | working.

  That is, the headlamp module 110 of Modification 1 according to Embodiment 1 includes a plurality of optical axis change regions 823 and 825. By doing in this way, the horizontal line 91,92,96 from which height differs can be included in the cut-off line 94 of the light distribution pattern 96e.

  That is, the headlamp module 110 can improve the visibility in the distance depending on the position where light is irradiated. Moreover, the headlamp module 110 can suppress dazzling according to the position where light is irradiated.

  It should be noted that the boundary surface between the optical axis changing regions 823 and 825 and the optical axis regions 821, 822 and 824 is preferably a smooth surface. This is because if there is an abrupt step on the boundary surface, processing is difficult and unnecessary light may be generated.

<Modification 2>
In the configuration of the headlamp module 100, the case where the light source 1 and the projection lens 8 are provided has been described. However, the headlamp module can include either the light collecting element 2 and the light shielding plate 50, or both.

  FIGS. 17A and 17B are configuration diagrams showing the configuration of the headlamp module 120 according to the second modification of the first embodiment. FIGS. 18A and 18B are configuration diagrams showing the configuration of the headlamp module 130 according to the second modification of the first embodiment.

  For example, the headlamp module 120 shown in FIG. 17 includes the condensing optical element 2 and the light shielding plate 50 in addition to the headlamp module 100 according to the first embodiment.

  The condensing optical element 2 converts the light emitted from the light source 1 into condensed light. The collected light is the collected light. The condensing optical element 2 condenses the light emitted from the light source 1.

  The condensing optical element 2 is located on the + Z axis side (front) of the light source 1. The condensing optical element 2 is positioned on the −Z axis side (rear side) of the light shielding plate 50.

  The condensing optical element 2 receives light emitted from the light source 1.

  The condensing optical element 2 condenses the light incident forward (+ Z-axis direction). The condensing optical element 2 is an optical element having a condensing function. That is, the condensing optical element 2 is an optical element having a positive power. In Modification 2, for example, the condensing optical element 2 condenses the light emitted from the light source 1 at the position of the light shielding plate 50. That is, the condensing optical element 2 condenses the light emitted from the light source 1 on the surface including the light shielding plate 50. The condensing optical element 2 has a condensing point on the surface including the light shielding plate 50.

  In FIG. 17, the condensing optical element 2 is shown as a convex lens having positive power.

  Moreover, the condensing optical element 2 shown in Embodiment 1 is filled with a refractive material, for example.

  In FIG. 17, the condensing optical element 2 is composed of one optical element, but a plurality of optical elements can also be used. However, when a plurality of optical elements are used, manufacturability is lowered, such as ensuring the positioning accuracy of each optical element.

  The light source 1 and the condensing optical element 2 are disposed behind the light shielding plate 50 (on the −Z axis direction side). The light source 1 is disposed behind the light shielding plate 50 (on the −Z axis direction side). The condensing optical element 2 is disposed behind the light shielding plate 50 (on the −Z axis direction side).

  The condensing optical element 2 is made of, for example, a transparent resin, glass, or silicone material. The material of the condensing optical element 2 is not limited as long as it has a property of transmitting light, and may be a transparent resin or the like. That is, the material of the optical element 2 only needs to have a function of transmitting light.

  However, from the viewpoint of light utilization efficiency, a material having a high function of transmitting light is suitable as the material of the condensing optical element 2. That is, it is desirable that the material of the condensing optical element 2 is transparent. Moreover, since the condensing optical element 2 is arrange | positioned immediately after the light source 1, the material excellent in heat resistance is preferable for the material of the condensing optical element 2. FIG.

  For example, as shown in FIG. 18, an optical element using light refraction and light reflection can be used for the condensing optical element 2.

  The condensing optical element 2 includes, for example, incident surfaces 211 and 212, a reflecting surface 22, and output surfaces 231 and 232.

  The incident surface 211 is an incident surface formed at the central portion of the condensing optical element 2. That is, the optical axis Cf of the condensing optical element 2 has an intersection on the incident surface 211.

  The incident surface 211 has a convex shape having a positive power. The convex shape of the incident surface 211 is convex in the −Z-axis direction. The power of the lens is also called “refractive power”. The incident surface 211 has, for example, a rotationally symmetric shape with the optical axis Cf of the condensing optical element 2 as a rotation axis.

  The incident surface 212 has, for example, a part of the surface shape of a rotating body that is rotated about the major axis or minor axis of an ellipse as a rotation axis. A rotating body that is rotated about the major axis or minor axis of the ellipse as a rotation axis is referred to as a “spheroid”. The rotation axis of the spheroid coincides with the optical axis Cf of the condensing optical element 2. The incident surface 212 has a surface shape obtained by cutting both ends in the rotation axis direction of the spheroid. That is, the incident surface 212 has a cylindrical shape.

  One end (+ z-axis direction side end) of the cylindrical surface of the incident surface 212 is connected to the outer periphery of the incident surface 211. The cylindrical shape of the incident surface 212 is formed on the −Z axis direction side with respect to the incident surface 211. That is, the cylindrical shape of the incident surface 212 is formed on the light source 1 side with respect to the incident surface 211.

  The reflecting surface 22 has a cylindrical shape in which the cross-sectional shape on the XY plane is, for example, a circle centered on the optical axis Cf of the condensing optical element 2. The cylindrical shape of the reflecting surface 22 is such that the circular diameter on the XY plane at the end on the −Z axis direction side is smaller than the circular diameter on the XY plane at the end on the + Z axis direction side. That is, the reflecting surface 22 has a diameter that increases from the −Z-axis direction to the + Z-axis direction. For example, the reflecting surface 22 has the shape of a side surface of a truncated cone. However, the shape of the reflecting surface 22 on the surface including the optical axis of the condensing optical element 2 may be a curved shape. “A plane including the optical axis” means that a line of the optical axis can be drawn on the plane.

  One end of the reflecting surface 22 in the cylindrical shape (end on the −Z axis direction side) is connected to the other end of the incident surface 212 in the cylindrical shape (end on the −Z axis direction side). That is, the reflecting surface 22 is located on the outer peripheral side of the incident surface 212.

  The exit surface 231 is located on the + Z axis direction side of the entrance surface 211. That is, the optical axis Cf of the condensing optical element has an intersection on the emission surface 231.

  The emission surface 231 has a convex shape having a positive power. The convex shape of the emission surface 231 is convex in the + Z-axis direction. The exit surface 213 has, for example, a rotationally symmetric shape with the optical axis Cf of the condensing optical element 2 as the rotation axis.

  The emission surface 232 is located on the outer peripheral side of the emission surface 231. The emission surface 232 has, for example, a planar shape parallel to the XY plane. The inner periphery and outer periphery of the emission surface 232 have a circular shape.

  The inner circumference of the emission surface 232 is connected to the outer circumference of the emission surface 231. The outer periphery of the emission surface 232 is connected to the other cylindrical end of the reflection surface 22 (the end on the + Z-axis direction side).

  The condensing optical element 2 only needs to be able to condense the light from the light source 1, and a mirror such as an elliptical mirror may be used as the condensing optical element 2.

  For example, the projection lens 8 has the same shape as the headlamp module 100 according to the first embodiment. That is, the exit surface 82 of the projection lens 8 includes a first optical axis region 821, a second optical axis region 822, and an optical axis change region 823.

  The light shielding plate 50 shields part of the light emitted from the light source 1. The light shielding plate 50 forms a cut-off line 94 for the light distribution pattern 95. The light distribution pattern 95 is formed by light that passes through the + Y-axis side of the light shielding plate 50.

  The light shielding plate 50 has a function of shielding part of the light emitted from the light source 1. For this reason, the light shielding plate 50 may be a light shielding surface formed in a part of the housing of the headlamp module 120, for example. The light shielding plate 50 is an example of a light shielding surface.

  In the headlamp modules 120 and 130 according to the modified example 2, the focal point of the projection lens 8 is located on the surface including the light shielding plate 50. That is, the focal point of the projection lens 8 in the Y-axis direction is located at the position of the light shielding plate 50 in the Z-axis direction. The focal point of the projection lens 8 is, for example, the focal point of the first optical axis region 821 and the focal point of the second optical axis region 822. As described above, the focal point of the projection lens 8 in the X-axis direction is not necessarily located at the position of the light shielding plate 50.

  That is, the light shielding plate 50 is optically conjugate with the irradiation surface 9 in the Y-axis direction. For this reason, the conjugate point becomes the focal point on the front side of the projection lens 8.

  FIG. 19 is a diagram illustrating an example of the shape of the light shielding plate 50 of the headlamp module 130 according to the second modification. The light shielding plate 50 includes a side 51. The side 51 corresponds to the cut-off line shape 54 shown in FIG. The light shielding plate 50 shields light in a horizontal shape by the side 51.

  The side 51 is a side on the + Y axis side of the light shielding plate 50. The light is transmitted through the + Y axis side of the side 51.

  The light shielding plate 50 is in an optically conjugate position with the irradiation surface 9 in the Y-axis direction. For this reason, the light distribution pattern in the Y-axis direction at the position of the light shielding plate 50 (conjugate surface PC) is similar to the light distribution pattern on the irradiation surface 9.

  The side 51 of the light shielding plate 50 has the same function as the end 111 of the light source 1 of the headlamp module 100 according to the first embodiment. That is, in the second modification, the shape of the light passing through the side 51 of the light shielding plate 50 is deformed by the projection lens 8.

  The cut-off line shape of the light distribution pattern at the position of the light shielding plate 50 is the shape of the side 51. That is, the cut-off line shape of the light distribution pattern at the position of the light shielding plate 50 is a linear shape.

  The projection lens 8 deforms this linear cut-off line shape. The projection lens 8 projects the deformed cut-off line light distribution pattern onto the irradiation surface 9. Accordingly, the headlamp modules 120 and 130 can generate the shape of the cut-off line 94.

  In this way, the headlamp modules 120 and 130 collect the light emitted from the light source 1 by the condensing optical element 2. The headlamp modules 120 and 130 block light by the light blocking plate 50. In the second modification, the light shielding plate 50 shields light in a linear shape. In the second modification, the light shielding plate 50 shields light horizontally. Thereby, even if the shape of the light source 1 is a shape other than a rectangle, the headlamp modules 120 and 130 can form a cut-off line shape using the projection lens 8.

  Further, in Comparative Example 1, it was necessary to shield light in a stepped shape like the light shielding plate 5 shown in FIG. However, in Modification 2, since the light is shielded horizontally, the amount of light to be shielded is smaller than that in Comparative Example 1. Therefore, the light utilization efficiency is improved.

  Moreover, by using the condensing optical element 2, more light emitted from the light source 1 can be taken in. The condensing optical element 2 can improve the brightness of the light distribution pattern 95. As a result, a small headlamp module with improved light utilization efficiency can be realized. If the brightness of the light distribution pattern 95 is sufficient, the condensing optical element 2 can be omitted.

<Modification 3>
In the third modification, the projection lens 8 is transformed into the light guide projection optical element 3. Modification 3 can also include the condensing optical element 2.

  FIGS. 20A and 20B are configuration diagrams showing the configuration of the headlamp module 140 according to the third modification of the first embodiment.

  As illustrated in FIG. 20, the headlamp module 140 according to the third modification of the first embodiment includes the light source 1 and the light guide projection optical element 3. Further, the headlamp module 140 can include the condensing optical element 2.

  The light guide projection optical element 3 has at least two optical axes. That is, the light guide projection optical element 3 has a plurality of optical axes.

  For example, in FIG. 20, the exit surface 33 of the light guide projection optical element 3 includes a first optical axis region 331, a second optical axis region 332, and an optical axis change region 333.

In order to facilitate the description of the light source 1 and the condensing optical element 2, X ₁ Y ₁ Z ₁ coordinates are used as a new coordinate system. The X ₁ Y ₁ Z ₁ coordinates are coordinates obtained by rotating the XYZ coordinates from the + X-axis direction by an angle a clockwise about the X-axis as a rotation axis.

In Modification 3, the optical axis Cf ₂ of the condensing optical element 2 is parallel to the _{Z 1} axis. Further, the optical axis Cf ₂ of the condensing optical element 2 coincides with the optical axis Cs of the light source 1.

<Light guide projection optical element 3>
The light guide projection optical element 3 is located in the + Z _1- axis direction of the light collection optical element 2. The light guide projection optical element 3 is located on the + Z axis side of the light collection optical element 2. The light guide projection optical element 3 is located on the −Y axis side of the light collection optical element 2.

  The light guide projection optical element 3 receives the light emitted from the condensing optical element 2. The light guide projection optical element 3 emits light forward (+ Z-axis direction).

  The light guide projection optical element 3 has a function of guiding light by the reflecting surface 32. Further, the light guide projection optical element 3 has a function of projecting light by the emission surface 33. For this reason, when explaining the optical element 3, it demonstrates as the light guide projection optical element 3 for easy understanding.

  The light guide projection optical element 3 includes a reflection surface 32 and an emission surface 33. The light guide projection optical element 3 can include an incident surface 31. The light guide projection optical element 3 can include an incident surface 34.

  The light guide projection optical element 3 is made of, for example, a transparent resin, glass or silicone material.

  Moreover, the light guide projection optical element 3 shown in the modified example 3 is filled with a refractive material, for example.

  The incident surface 31 is provided at the end of the light guide projection optical element 3 on the −Z axis direction side. The incident surface 31 is provided at a portion on the + Y-axis direction side of the light guide projection optical element 3.

  20A and 20B, the incident surface 31 of the light guide projection optical element 3 has a curved shape. The curved surface shape of the incident surface 31 is, for example, a convex shape having positive power in both the horizontal direction (X-axis direction) and the vertical direction (Y-axis direction).

  The incident surface 31 may have a planar shape. Further, the incident surface 31 may have power in one of the horizontal direction (X-axis direction) and the vertical direction (Y-axis direction). That is, the incident surface 31 may be a cylindrical lens surface. Further, the incident surface 31 may have a negative power in the horizontal direction (X-axis direction).

  The divergence angle of the light incident on the curved incident surface 31 changes. The incident surface 31 can shape a light distribution pattern by changing the divergence angle of light. That is, the incident surface 31 has a function of shaping the shape of the light distribution pattern. That is, the incident surface 31 functions as a light distribution pattern shape forming part.

  Further, for example, it may be possible to omit the condensing optical element 2 by providing the incident surface 31 with a condensing function. That is, the incident surface 31 functions as a light collecting unit.

  The incident surface 31 is considered as an example of the light distribution pattern shape forming part. Further, the incident surface 31 can be considered as an example of a light collecting unit.

  The reflecting surface 32 is provided at the end of the incident surface 31 on the −Y axis direction side. That is, the reflecting surface 32 is disposed on the −Y axis direction side of the incident surface 31. The reflecting surface 32 is disposed on the + Z axis direction side of the incident surface 31. In Modification 3, the end of the reflecting surface 32 on the −Z-axis direction side is connected to the end of the incident surface 31 on the −Y-axis direction side.

  The reflection surface 32 reflects light that has reached the reflection surface 32. That is, the reflecting surface 32 has a function of reflecting light. That is, the reflecting surface 32 functions as a light reflecting portion. The reflecting surface 32 is considered as an example of a light reflecting portion.

  The reflection surface 32 is a surface facing in the + Y axis direction. That is, the surface of the reflecting surface 32 is a surface facing in the + Y axis direction. The surface of the reflecting surface 32 is a surface that reflects light. The back surface of the reflecting surface 32 is a surface facing in the −Y axis direction.

  The reflecting surface 32 is a surface that rotates clockwise with respect to the Z-X plane with the axis parallel to the X axis as the center when viewed from the + X axis direction. In FIG. 20, the reflecting surface 32 is a surface rotated by an angle b with respect to the Z-X plane.

  In FIG. 20, the reflecting surface 32 is shown as a plane. However, the reflecting surface 32 does not have to be a flat surface. The reflection surface 32 may have a curved surface shape.

  The reflection surface 32 is, for example, a total reflection surface. However, the reflecting surface 32 may be a mirror surface by mirror deposition. However, it is desirable that the reflection surface 32 function as a total reflection surface without mirror deposition. This is because the total reflection surface has a higher reflectance than the mirror surface and contributes to an improvement in light utilization efficiency.

  The ridge line portion 321 is a side of the reflecting surface 32 on the −Y axis direction side. The ridge line portion 321 is a side on the + Z-axis direction side of the reflection surface 32. The ridge line portion 321 is at a position optically conjugate with the irradiation surface 9 in the Y-axis direction.

  The ridge line portion 321 corresponds to the side 51 of the light shielding plate 50 shown in FIG. However, in Modification 3, the light utilization efficiency is higher than that of the light shielding plate 50 because the light is not reflected and reflected by the reflecting surface 32.

  The “ridge line” is generally a boundary line between surfaces. However, here, the “ridgeline” includes the edge of the surface. In the third modification, the ridge line portion 321 is a portion that connects the reflecting surface 32 and the incident surface 34. That is, the connecting portion between the reflecting surface 32 and the incident surface 34 is the ridge line portion 321.

  However, for example, when the inside of the light guide projection optical element 3 is hollow and the incident surface 34 is an opening, the ridge line portion 321 is the end of the reflecting surface 32. That is, the ridge line portion 321 includes a boundary line between the surfaces. Further, the ridge line portion 321 includes an end portion of the surface. As described above, in the first embodiment, the inside of the light guide projection optical element 3 is filled with a refractive material.

  Further, the “ridge line” is not limited to a straight line but also includes a curved line. In the third modification, the ridge line portion 321 has a linear shape. In the third modification, the ridge line portion 321 has a linear shape parallel to the X axis.

  In the third modification, the ridge line portion 321 is a side on the + Y axis direction side of the incident surface 34. Since the ridge line portion 321 is also on the incident surface 34, it is at a position optically conjugate with the irradiation surface 9 in the Y-axis direction.

  In the headlamp module 140 according to the modified example 3, the focal point of the emission surface 33 of the light guide projection optical element 3 is located on the surface including the ridge line portion 321. That is, in the Z-axis direction, the focal point in the Y-axis direction of the exit surface 33 of the light guide projection lens 3 is located at the position of the ridge line portion 321. The focal points of the emission surface 33 are, for example, the focal point of the first optical axis region 331 and the focal point of the second optical axis region 332.

  That is, the ridge line portion 321 is optically conjugate with the irradiation surface 9 in the Y-axis direction. For this reason, the conjugate point becomes the focal point on the front side of the emission surface 33.

  The ridge portion 321 is optically conjugate with the irradiation surface 9 in the Y-axis direction. For this reason, the light distribution pattern in the Y-axis direction at the position of the ridge line portion 321 (conjugate surface PC) is similar to the light distribution pattern on the irradiation surface 9.

  The ridge line part 321 has the same function as the end part 111 of the light source 1 of the headlamp module 100 according to the first embodiment. That is, in the third modification, the shape of the light passing through the ridge line portion 321 is deformed by the emission surface 33 of the light guide projection optical element 3. The cut-off line shape of the light distribution pattern at the position of the ridge line portion 321 is a linear shape. The light guide projection optical element 3 deforms this linear cut-off line shape. The light guide projection optical element 3 projects the deformed cut-off line light distribution pattern onto the irradiation surface 9. As a result, the headlamp module 140 can generate the shape of the cut-off line 94.

In the third modification, the ridge line portion 321 intersects the optical axis Cp ₁ of the exit surface 33 of the light guide projection optical element 3 at a right angle. Optical axis Cp ₂ is perpendicular to the conjugate plane PC. The conjugate plane PC is a plane including the ridge line portion 321.

The optical axis Cp ₁ is the optical axis of the fourth optical axis region 331 of the emission surface 33. The optical axis Cp ₂ is the optical axis of the fifth optical axis region 332 of the emission surface 33.

  The exit surface 33 is provided at the end of the light guide projection optical element 3 on the + Z-axis direction side. The emission surface 33 has a curved surface shape having a positive power. The emission surface 33 has a convex shape protruding in the + Z-axis direction.

  The shape of the emission surface 33 has the same function as the emission surface 82 of the projection lens 8 of the headlamp module 100 according to the first embodiment.

  That is, in the example of FIG. 20, the fourth optical axis region 331, the fifth optical axis region 332, and the optical axis change region 333 are the first optical axis region of the projection lens 8 of the headlamp module 100 according to Embodiment 1. 821, the second optical axis region 822, and the optical axis change region 823, respectively.

<Behavior of light>
As shown in FIG. 20, the light condensed by the condensing optical element 2 enters the light guide projection optical element 3 from the incident surface 31.

  The incident surface 31 is a refractive surface. The incident surface 31 refracts light. The light incident on the incident surface 31 is refracted by the incident surface 31. The incident surface 31 has a convex shape protruding in the −Z-axis direction.

  Here, the curvature of the incident surface 31 in the X-axis direction contributes to the “light distribution width” in the horizontal direction with respect to the road surface. Further, the curvature of the incident surface 31 in the Y-axis direction contributes to the “light distribution height” in the direction perpendicular to the road surface.

<< Behavior of rays on the Z-X plane >>
When viewed in the ZX plane, the incident surface 31 has a convex shape. That is, the incident surface 31 has positive power in the horizontal direction (X-axis direction). Here, “view in the ZX plane” means to view from the Y-axis direction. That is, it is projected on the ZX plane and viewed. For this reason, the light incident on the incident surface 31 is further condensed and propagated on the incident surface 31 of the light guide projection optical element 3. Here, “propagation” means that light travels through the light guide projection optical element 3.

  When viewed in the Z-X plane, the light propagating through the light guide component 3 is guided by the light-converging optical element 2 and the incident surface 31 of the light guide projection optical element 3 as shown in FIG. 3 is condensed at a light condensing position PH inside. In FIG. 20B, the condensing position PH is indicated by a broken line. In FIG. 20B, the position of the ridge line portion 321 is the position of the conjugate plane PC. In FIG. 20B, the condensing position PH is made to coincide with the conjugate plane PC.

  On the ZX plane, the condensing position PH can also be arranged on the −Z axis side with respect to the conjugate plane PC. Further, the condensing position PH can also be arranged on the + Z axis side from the conjugate plane PC. It is also possible not to have the condensing position PH. By these, the width of the light beam in the X-axis direction on the conjugate plane PC can be controlled. And the width | variety of the light distribution pattern which the headlamp module 140 radiate | emits can be changed.

  The spread of the light divergence angle on the conjugate plane PC corresponds to the “light distribution width” on the irradiation surface 9. That is, the spread of the divergence angle of the light on the conjugate plane PC can also be controlled by changing the curvature of the curved shape of the incident surface 31. Thereby, the width | variety of the light distribution pattern which the headlamp module 140 radiate | emits can be changed.

<< Behavior of rays on the ZY plane >>
On the other hand, when the light incident from the incident surface 31 is viewed on the YZ plane, the light refracted by the incident surface 31 propagates through the light guide projection optical element 3 and is guided to the reflecting surface 32.

  The light that enters the light guide projection optical element 3 and reaches the reflection surface 32 enters the light guide projection optical element 3 and directly reaches the reflection surface 32. “Directly reaching” means reaching without being reflected by another surface or the like.

  The light that enters the light guide projection optical element 3 and reaches the reflection surface 32 reaches the reflection surface 32 without being reflected by another surface or the like. That is, the light that reaches the reflecting surface 32 is first reflected in the light guide projection optical element 3.

  The light reflected by the reflecting surface 32 is directly emitted from the emitting surface 33. That is, the light reflected by the reflection surface 32 reaches the emission surface 33 without being reflected by another surface or the like. On the ZY plane, that is, the light that first reflected on the reflecting surface 32 reaches the exit surface 33 by this one reflection.

In FIG. 20, the light emitted from the + Y ₁ axis direction side from the optical axis Cp _{2 of the} condensing optical element 2 out of the exit surfaces 231 and 232 of the condensing optical element 2 is guided to the reflecting surface 32. . In addition, the light emitted from the −Y ₁ axis direction side of the optical axis Cp _{2 of the} condensing optical element 2 out of the emission surfaces 231 and 232 of the condensing optical element 2 is not reflected by the reflecting surface 32. The light is emitted from the emission surface 33.

  That is, part of the light incident on the light guide projection optical element 3 reaches the reflection surface 32. The light that reaches the reflection surface 32 is reflected by the reflection surface 32 and emitted from the emission surface 33.

  Note that, by setting the inclination angle a of the light source 1 and the condensing optical element 2, all the light emitted from the condensing optical element 2 can be reflected by the reflecting surface 32. Further, by setting the inclination angle b of the reflecting surface 32, all the light emitted from the condensing optical element 2 can be reflected by the reflecting surface 32.

  Moreover, the length of the light guide projection optical element 3 in the optical axis Cp direction (Z-axis direction) can be shortened by setting the inclination angle a of the light source 1 and the condensing optical element 2. And the depth (length in the Z-axis direction) of the optical system can be shortened. Here, in the third modification, the “optical system” is an optical system having the condensing optical element 2 and the light guide projection optical element 3 as components.

  Further, by setting the inclination angle a of the light source 1 and the condensing optical element 2, the light emitted from the condensing optical element 2 can be easily guided to the reflecting surface 32. For this reason, it becomes easy to efficiently collect light in a region on the inner side (+ Y-axis direction side) of the ridge line portion 321 on the conjugate plane PC.

  That is, by collecting the light emitted from the condensing optical element 2 on the conjugate plane PC side of the reflecting surface 32, the amount of light emitted from the + Y-axis direction region of the ridge line portion 321 can be increased. In this case, the intersection between the central ray emitted from the condensing optical element 2 and the reflecting surface 32 is located on the conjugate plane PC side of the reflecting surface 32.

  Therefore, it becomes easy to brighten the area below the cut-off line 94 of the light distribution pattern projected onto the irradiation surface 9. In addition, since the length of the light guide projection optical element 3 in the optical axis Cp direction (Z axis direction) is shortened, the internal absorption of light of the light guide projection optical element 3 is reduced, and the light use efficiency is improved. “Internal absorption” refers to light loss inside the material, excluding loss of surface reflection when light passes through the light guide component (light guide projection optical element 3 in Modification 3). Internal absorption increases as the length of the light guide component increases.

  In a general light guide element, light repeatedly reflects on the side surface of the light guide element and travels inside the light guide element. Thereby, the light intensity distribution is made uniform. In the third modification, the light incident on the light guide projection optical element 3 is reflected once by the reflection surface 32 and emitted from the emission surface 33. In this respect, the method of using the light guide projection optical element 3 of the present application is different from the method of using the conventional light guide element.

  In order to generate a light distribution pattern in which the area below the cut-off line 94 (−Y-axis direction side) has the maximum illuminance, as shown in FIG. It is effective to reflect a part of light incident from the incident surface 31 of the light guide projection optical element 3 by the reflecting surface 32.

  This is because, among the light incident from the incident surface 31, the light that has not been reflected by the reflecting surface 32 and has reached the + Y-axis direction side of the ridge line portion 321 and the light that has been reflected on the reflecting surface 32 are on the conjugate plane PC. This is because they are superimposed.

  That is, in the area on the conjugate plane PC corresponding to the high illuminance area on the irradiation surface 9, the light that has reached the conjugate plane PC without being reflected by the reflecting plane 32 and reflected on the reflecting plane 32 to the conjugate plane PC. Superimpose the light that arrives. With such a configuration, the luminous intensity of the region on the upper side (+ Y-axis direction side) of the ridge line portion 321 can be made highest among the luminous intensity on the conjugate plane PC.

  A region having a high luminous intensity is formed by superimposing the light that has reached the conjugate plane PC without being reflected by the reflecting plane 32 and the light that has been reflected by the reflecting plane 32 and has reached the conjugate plane PC on the conjugate plane PC. doing. The position of the region with high luminous intensity on the conjugate plane PC can be changed by changing the reflection position of the light on the reflecting surface 32.

  By bringing the light reflection position on the reflection surface 32 closer to the conjugate plane PC, the vicinity of the ridge line portion 321 on the conjugate plane PC can be set as a region with high luminous intensity. That is, the lower side of the cut-off line 94 on the irradiation surface 9 can be a region with high illuminance.

  Further, the amount of the superimposed light can be adjusted by arbitrarily changing the curvature of the incident surface 31 in the vertical direction (Y-axis direction) as in the case of adjusting the width of the light distribution in the horizontal direction. it can. The “amount of superimposed light” refers to the light (on the conjugate plane PC) that reaches the + Y-axis direction side of the ridge line portion 321 without being reflected by the reflecting surface 32 and the light that is reflected on the reflecting surface 32. This is the amount of light superimposed.

  In the above description, the high illuminance area is described as the area on the lower side (−Y axis direction side) of the cutoff line 94. This is the position of the high illuminance region of the light distribution pattern on the irradiation surface 9.

  In the Y-axis direction, the image of the light distribution pattern formed on the conjugate plane PC is enlarged and projected onto the irradiation surface 9 in front of the vehicle by the light guide projection optical element 3.

The focal point of the emission surface 33 in the Y-axis direction is located on a plane parallel to the XY plane including the ridge line portion 321. The focal point of the fourth optical axis region 331 is on the optical axis Cp _1. The focal point of the fifth optical axis region 332 is on the optical axis Cp _2.

That is, the focal point in the Y-axis direction of the fourth optical axis region 331 of the emission surface 33 is at the intersection of the plane parallel to the XY plane including the ridge line portion 321 and the optical axis Cp ₁ . Further, the focal point of the Y-axis direction of the fifth optical axis region 332 of the surface 33 lies at the intersection of the X-Y plane parallel to the plane and the optical axis Cp ₂ including the ridge line portion 321.

In the conventional headlamp, since the light shielding plate and the projection lens are used, a change such as a cut-off line deformation or a light distribution variation due to a position variation between components occurs. However, the light guide projection optical element 3 can make the focal position of the emission surface 33 coincide with the position of the ridge line portion 321 in the optical axis Cp ₁ and optical axis Cp ₂ directions with the shape accuracy of one component.

  Accordingly, the headlamp module 100 can suppress changes such as cut-off line deformation or light distribution variation. This is because, generally, the shape accuracy of one component can be improved more easily than the positional accuracy between two components.

  In addition, the diameter of the exit surface 33 can be reduced by inclining the reflecting surface 32 so that the optical path in the light guide projection optical element 3 spreads in the light traveling direction (+ Z-axis direction).

  The reflecting surface 32 is inclined so as to face the exit surface 33 side in the direction of the optical axis Cp of the exit surface 33, whereby the aperture of the exit surface 33 can be reduced.

  The reflection surface 32 is formed in a curved surface that faces the emission surface 33 side in the direction of the optical axis of the emission surface 33.

  By the inclination of the reflection surface 32, the aperture of the emission surface 33 can be reduced. And the headlamp module 140 can be reduced in size. In particular, the headlamp module 140 contributes to a reduction in thickness in the height direction (Y-axis direction).

  The headlamp module 140 can change the width and height of the light distribution pattern by adjusting the curved surface shape of the incident surface 31 of the light guide projection optical element 3. And the light distribution can also be changed.

  Further, the headlamp module 140 adjusts the optical positional relationship between the condensing optical element 2 and the light guide projection optical element 3 or the shape of the incident surface 31 of the light guide projection optical element 3 to thereby adjust the light distribution pattern. The width and height of the can be changed. And the light distribution can also be changed.

  In addition, by using the reflecting surface 32, it is possible to easily change the light distribution. For example, the position of the high illuminance region can be changed by changing the inclination angle b of the reflection surface 32.

  For this reason, it is not particularly necessary to change the shape of the condensing optical element 2 between the plurality of headlamp modules. That is, the condensing optical element 2 can be a common component. For this reason, the kind of components can be reduced, assemblability can be improved, and manufacturing cost can be reduced.

  In addition, the function of arbitrarily adjusting the width and height of such a light distribution pattern and the function of arbitrarily adjusting the light distribution need only be exhibited by the entire headlamp module 140. The optical component of the headlamp module 140 includes a condensing optical element 2 and a light guide projection optical element 3. That is, these functions can be distributed to any one of the optical surfaces of the condensing optical element 2 and the light guide projection optical element 3 constituting the headlamp module 140.

  For example, it is possible to form a light distribution by providing the reflecting surface 32 of the light guide projection optical element 3 with a curved surface to give power.

  However, with respect to the reflecting surface 32, it is not always necessary that all light reaches the reflecting surface 32. For this reason, when the reflecting surface 32 is shaped, the amount of light that can contribute to the shaping of the light distribution pattern is limited. That is, the amount of light that can be applied to the light distribution pattern by the shape of the reflecting surface 32 by being reflected by the reflecting surface 32 is limited. Therefore, in order to optically act on all the light and easily change the light distribution pattern, it is preferable to form the light distribution by giving power to the incident surface 31.

  The headlamp module 140 includes a light source 1, a condensing optical element 2, and a light guide projection optical element 3. The light source 1 emits light. The condensing optical element 2 condenses the light emitted from the light source 1. The light guide projection optical element 3 makes the light emitted from the condensing optical element 2 incident from the incident surface 31, reflects the incident light by the reflecting surface 32, and emits the light from the emitting surface 33. The incident surface 31 is formed as a curved surface that changes the divergence angle of incident light.

  The headlamp module 140 includes the light source 1 and the optical element 3. The light source 1 emits light. The optical element 3 includes a reflection surface 32 that reflects the light emitted from the light source 1 and an emission surface 33 that emits the reflected light reflected by the reflection surface 32. The exit surface 33 has a positive refractive power. In the optical axis Cp direction of the emission surface 33, the end 321 of the reflection surface 32 on the emission surface 33 side includes a point T located at the focal position of the emission surface 33.

  In the modification 3, the optical element 3 is shown as the light guide projection optical element 3 as an example. Moreover, the edge part 321 is shown as the ridgeline part 321 as an example.

  The end 321 of the reflection surface 32 in the traveling direction of the reflected light includes a point T located at the focal position of the emission surface 33 in the direction of the optical axis Cp of the emission surface 33.

Embodiment 2. FIG.
FIG. 21 is a configuration diagram showing a configuration of the headlamp device 10 in which the headlamp modules 100, 110, 120, 130, and 140 are mounted. In the above-described embodiment, the embodiments of the headlamp modules 100, 110, 120, 130, and 140 have been described. FIG. 21 shows an example in which the headlamp module 100 is mounted as an example.

  For example, all or part of the three headlight modules 100 shown in FIG. 21 can be replaced with the headlight modules 110, 120, 130, and 140.

  The headlamp device 10 includes a housing 97. The headlamp device 10 can include an outer lens 96.

  The casing 97 holds the headlamp module 100.

  The casing 97 is disposed, for example, inside the vehicle body.

  A headlamp module 100 is housed inside the casing 97. In FIG. 21, three headlight modules 100 are housed as an example. The number of headlamp modules 100 is not limited to three. The number of headlamp modules 100 may be one or two, or four or more.

  For example, the headlamp module 100 is arranged in the X-axis direction inside the housing 97. Note that the method of arranging the headlamp modules 100 is not limited to the method of arranging them in the X-axis direction. The headlamp module 100 may be shifted in the Y-axis direction or the Z-axis direction in consideration of the design or function.

  In FIG. 21, the headlamp module 100 is housed inside the housing 97. However, the casing 97 does not have to be box-shaped. The casing 97 is configured by a frame or the like, and a configuration in which the headlamp module 100 is fixed to the frame may be employed. This is because the casing 97 is disposed inside the vehicle body in the case of a four-wheeled automobile or the like. The frame or the like may be a part constituting the vehicle body. In this case, the casing 97 becomes a part constituting the vehicle body. That is, the housing 97 becomes a housing portion.

  In the case of a motorcycle, the casing 97 is disposed near the handle. In the case of a four-wheeled automobile, the casing 97 is disposed inside the vehicle body.

  The outer lens 96 transmits light emitted from the headlamp module 100. And the light which permeate | transmitted the outer lens 96 is radiate | emitted ahead of a vehicle. The outer lens 96 is made of a transparent material.

  The outer lens 96 is disposed on the surface portion of the vehicle body and appears outside the vehicle body.

  The outer lens 96 is disposed in the + Z axis direction of the housing 97.

  The light emitted from the headlamp module 100 passes through the outer lens 96 and is emitted forward (+ Z-axis direction) of the vehicle. In FIG. 17, the light emitted from the outer lens 96 overlaps with the light emitted from the adjacent headlamp modules 100 to form one light distribution pattern.

  The outer lens 96 is provided to protect the headlamp module 100 from wind and rain or dust. However, in the case where the projection lens 8 has a structure that protects the internal components of the headlamp module 100 from wind and rain or dust, it is not necessary to provide the outer lens 96 in particular.

  As described above, when a plurality of headlamp modules 100 are provided, the headlamp device 10 is an aggregate of the headlamp modules 100. When the single headlamp module 100 is provided, the headlamp device 10 is equal to the headlamp module 100. That is, the headlamp module 100 is the headlamp device 10. Alternatively, the headlamp device 10 has a configuration in which an outer lens 96 or a casing 97 is attached to one headlamp module 100.

  In each of the above-described embodiments, there are cases where terms indicating the positional relationship between components or the shape of the components, such as “parallel” or “vertical”, are used. These include ranges that take into account manufacturing tolerances and assembly variations. For this reason, when the claims indicate the positional relationship between the parts or the shape of the parts, these descriptions include a range that takes into account manufacturing tolerances, assembly variations, and the like.

  Moreover, although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

DESCRIPTION OF SYMBOLS 10 Headlamp apparatus, 100,100a, 100b, 101,110,120,130,140 Headlamp module, 1 Light source, 11 Light-emitting surface, 111 End, 2 Condensing optical element, 211,212 Incident surface, 22 Reflective surface, 231, 232 exit surface, 3 light guide projection optical element 3, 31, 34 entrance surface, 32 reflective surface, 33 exit surface, 331 fourth optical axis region, 332 fifth optical axis region, 333 optical axis change region 5, 50 light-shielding plate, 51, 52, 53 sides, 54 cut-off line shape, 8, 8a, 8b, 8c, 8d projection lens, 81 entrance surface, 82 exit surface, 821 first optical axis region, 822 second Optical axis region, 824 Third optical axis region, 823,825 Optical axis change region, 9 Irradiation surface, 91, 92, 96 Horizontal line, 93, 97 Rising line, 94 Cut-off line , 95,95a, 95b, 95c, 95d , 95e light distribution pattern, 96 the outer lens, 97 a _{housing, Cs, Cp, Cp 1,} Cp 2, Cp 3, Cf, Cf 2 optical axis, a1, a2, a3, a4, a5, a6 angles, PC conjugate plane, P, Q, T point, R11, R12, R21, R22, R31, R32, R33 rays.

Claims (9)

A light source including a light emitting surface for emitting light;
A headlamp module comprising: a projection optical element that receives the light and changes and projects a light distribution pattern formed by the light. The projection optical element includes a first optical axis region and a second optical axis region,
2. The headlamp module according to claim 1, wherein a focal point of the first optical axis region and a focal point of the second optical axis region are located at different positions on a surface including the light distribution pattern. A headlamp module mounted on a vehicle,
The direction different from the focal position of the first optical axis region and the focal position of the second optical axis region is a direction corresponding to a vertical direction of a light distribution pattern projected by the headlamp module. 2. The headlamp module according to 2.   The headlamp module according to any one of claims 1 to 3, wherein the light distribution pattern has a light emission shape formed on the light emitting surface. A light shielding surface that shields a part of the light emitted from the light emitting surface;
The headlamp module according to any one of claims 1 to 3, wherein the light distribution pattern is a shape of a light beam formed on a surface including the light shielding surface. A condensing optical element that condenses the light emitted from the light emitting surface;
The headlamp module according to claim 5, wherein the condensing optical element has a condensing function in at least one direction on a surface where the light distribution pattern is formed.   The headlamp module according to claim 6, wherein the condensing optical element has a condensing point on a surface on which the light distribution pattern is formed. The projection optical element includes a reflecting surface that reflects light emitted from the light emitting surface,
The light distribution pattern is changed on the exit surface of the projection optical element,
The headlamp module according to any one of claims 1 to 3, wherein the light distribution pattern is formed at an end of the reflecting surface on the emission surface side.   A headlamp device comprising the headlamp module according to any one of claims 1 to 8.

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