JP2011119184A - Headlight for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector type headlight for a vehicle, switching between light distribution patterns for low beams and for high beams, in which hot zones for both the light distribution pattern for low beams and the light distribution pattern for high beams secure sufficient brightness, and each light distribution pattern contains the optimal shape and a light intensity distribution. <P>SOLUTION: A light source 2 is arranged at a first focal point f1 of a sub-reflecting surface 11b with a light-emitting axis facing upward and to a sub-reflecting surface 11b side, a movable mirror 20 having a plane reflecting surface 20a is fitted at a space with a projection lens 30 having a back side focal point f3 on an optical axis X<SB>L</SB>passing through the light source 2. When a front end edge side of the movable mirror 20 is inclined downward of the optical axis X<SB>L</SB>, a second focal point f2b of the sub-reflecting surface 11b positioned under the plane reflecting surface 20a is made placed in a plane-symmetrical position with the plane reflecting surface 20a as a symmetrical surface to the back side focal point f3 of the projection lens 30. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle headlamp, and more particularly to a projector-type vehicle headlamp capable of switching between a low beam light distribution pattern and a high beam light distribution pattern.

  A configuration of a conventional vehicle headlamp of this type is disclosed in Japanese Patent Laid-Open No. 2000-348508 (see FIGS. 11 and 12).

  In the disclosed vehicle headlamp 80, the main parts of its optical system are provided on a light source 81, a reflecting mirror 82 having an elliptical reflecting surface 82a, a flat shield part 83a, and one surface of the shield part 83a. The shield plate 83 and the projection lens 84 are composed of the inner mirror part 83b and the rotation support part 83c.

  The elliptical reflecting surface 82a of the reflecting mirror 82 has a half shape when the spheroidal surface is divided into approximately two equal parts along the major axis z, and the light source 81 is arranged at the position of the first focal point f1. The shielding plate 83 is disposed between the first focal point f1 and the second focal point f2 of the elliptical reflecting surface 82a, and the planar inner mirror part 83b of the shielding plate 83 is along the major axis z and is elliptically reflecting. The end opposite to the surface 82a and opposite to the rotation support portion 83c is located in the vicinity of the position of the second focal point f2 of the elliptical reflecting surface 82a.

  The projection lens 84 is arranged so that the vicinity of the position of the second focal point f2 of the elliptical reflecting surface 82a is the position of the rear focal point, and the optical axis coincides with the long axis z.

  By configuring the optical system as described above, as shown in FIG. 11, the shielding plate 83 is rotated to the low beam (passing beam) light distribution pattern forming position s with the rotation support portion 83c as the center of rotation. Then, the light (reflected light) emitted from the light source 81 toward the elliptical reflecting surface 82a and reflected by the elliptical reflecting surface 82a is reflected directly by the light focused on the second focal point f2 and the inner mirror part 83b. Then, it is divided into light that forms an image at the second focal point f2, and a semicircular image formed by all the light reflected by the elliptical reflecting surface 82a is formed at the second focal point f2.

  This semi-circular image has an area approximately halved and the luminance almost doubled as compared with the circular image, and this image is projected through the projection lens 84 in the downward direction of the irradiation direction to generate a low beam. A bright light distribution pattern can be obtained.

  On the other hand, as shown in FIG. 12, when the shielding plate 83 is rotated to the high beam (traveling beam) light distribution pattern forming position m with the rotation support portion 83c as the center of rotation, the light source 81 to the elliptical reflection surface 82a. The light (reflected light) emitted toward and reflected by the elliptical reflecting surface 82a forms a circular image at the second focal point f2 without being shielded, and this image is irradiated through the projection lens 84. A light distribution pattern for a high beam is obtained by projecting in a direction including upward direction.

JP 2000-348508 A

  By the way, in the above-described conventional vehicle headlamp, the hot zone, which is the high luminous intensity region of the low beam light distribution pattern, is formed by the reflected light reflected by the inner mirror part 83b. Therefore, the brightness of the hot zone of the high beam light distribution pattern that does not use the reflected light by the inner mirror part 83b is darker than the brightness of the hot zone of the low beam light distribution pattern, and sufficient brightness cannot be obtained. It is impossible to make the high beam light distribution pattern excellent in distance visibility.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a low-beam projector-type vehicle headlamp capable of switching between a low-beam light distribution pattern and a high-beam light distribution pattern. Both the hot zone of the light distribution pattern for the light and the hot zone of the light distribution pattern for the high beam can ensure sufficient brightness, and each light distribution pattern has an optimal shape and light intensity distribution. .

  In order to solve the above-mentioned problems, the invention described in claim 1 of the present invention is characterized in that two rotations each composed of a spheroidal surface or a similar rotational free-form surface, which are connected in common while sharing the position of the first focal point. The main reflecting surface formed on the one spheroid surface and the other spheroid formed on the one spheroid surface that is positioned substantially above when the ellipsoidal surface is divided into upper and lower planes including the major axis of the one spheroid surface A complex ellipsoidal reflecting surface comprising a sub-reflecting surface formed on a system curved surface and having the rear end of the sub-reflecting surface connected to the front end of the main reflecting surface, and located near the first focal point; A light source having a light emitting axis directed upward and forward; a projection lens having the long axis as an optical axis and a rear focal point located at the same position as the second focal point of the main reflecting surface on the optical axis; the light source; Located between the projection lens and the upper surface as a plane reflecting surface, on the rear edge side A vehicular headlamp having a moving support portion and a movable mirror whose front end edge side is turned up and down with the turning support portion as a fulcrum, wherein the plane reflecting surface of the movable mirror is in the vicinity of the optical axis And at a position along the optical axis, the front end edge of the movable mirror is positioned near the rear focal point of the projection lens, and the light emitted from the light source and reflected by the main reflection surface is When the light is irradiated to the outside through the projection lens through the rear focal point, and the reflecting surface of the movable mirror is inclined downward at a predetermined angle with respect to the optical axis, the reflection is performed. The second focal point of the sub-reflecting surface, which is located below the surface, is in a plane-symmetrical position with the planar reflecting surface as a symmetric surface with respect to the rear focal point, and is emitted from the light source and is the main reflecting surface. The reflected light passes through the rear focal point and through the projection lens. The primary reflected light reflected by the sub-reflecting surface is reflected again by the planar reflecting surface, and the secondary reflected light passes through the rear focal point and radiates to the outside through the projection lens. It is characterized by that.

  The invention described in claim 2 of the present invention is characterized in that, in claim 1, the solid angle at which the light source expects the main reflection surface is larger than the solid angle at which the sub reflection surface is expected. is there.

  In the present invention, at the time of forming a high beam light distribution pattern, light emitted from a light source whose emission axis is directed to the sub-reflecting surface side sequentially, the sub-reflecting surface, the plane reflecting surface of the movable mirror, the rear focal point of the projection lens, and An optical system related to the formation of an optical path irradiated outside through the projection lens is configured.

  As a result, the light emitted from the light source arranged with the light emitting axis facing the sub-reflecting surface side irradiates through the optical system forms a hot zone in the high beam light distribution pattern. It greatly contributed to the increase in luminous intensity.

  Also, by setting the light quantity ratio of the light emitted from the light source toward the main reflection surface and the light toward the sub-reflection surface to an appropriate ratio, a low beam light distribution pattern formed only by the reflected light of the main reflection surface, In addition, the brightness balance between the light distribution pattern for high beam formed by the reflected light of the main reflecting surface and the reflected light of the sub-reflecting surface can be set to an optimum state.

  As a result, both the low-beam light distribution pattern and the high-beam light distribution pattern can have good visibility, and the forward confirmation during night driving can be ensured.

It is explanatory drawing which looked at the embodiment from the diagonal direction. It is explanatory drawing by the longitudinal cross-section of FIG. It is explanatory drawing which looked at the embodiment from the diagonal direction. It is explanatory drawing by the longitudinal cross-sectional view of FIG. It is explanatory drawing of the optical system concerning embodiment. Similarly, it is explanatory drawing of the optical system concerning embodiment. It is explanatory drawing of the light distribution pattern concerning embodiment. Similarly, it is explanatory drawing of the light distribution pattern concerning embodiment. It is explanatory drawing regarding the solid angle which a light source anticipates of embodiment. Similarly, it is explanatory drawing regarding the solid angle which the light source anticipates of embodiment. It is explanatory drawing of a prior art example. Similarly, it is explanatory drawing of a prior art example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 10 (the same parts are denoted by the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  In addition, the terms indicating the directions such as “horizontal”, “vertical”, “front”, “rear”, “lower”, “upper” and the like used in the following description are in the state where the vehicle headlamp is mounted on the vehicle. Meaning “horizontal to the road surface”, “perpendicular to the road surface”, “irradiation direction of the lamp”, “direction opposite to the irradiation direction of the lamp”, “direction toward the road surface”, “direction toward the opposite side of the road surface” It is. Among them, “front” and “rear” are also “a direction from the light source toward the projection lens” and “a direction from the projection lens toward the light source” as described later, respectively.

  1 to 4 schematically show the structure of the main part of the vehicle headlamp according to the present invention. Of these, FIGS. FIG. 3 and FIG. 4 show a state when a high beam (traveling beam) light distribution pattern is formed.

  The main part of the vehicle headlamp according to the present invention includes a light source module 1, a reflector 10, a movable mirror 20, a projection lens 30, a lens holder 40, a heat sink 50, and a rotation mechanism 60.

  The light source module 1 includes a light source 2, a substrate 3 provided with the light source 2, and a metal plate 4 on which the substrate 3 is mounted.

  The light source 2 includes a light emitting source (light emitting element) that can be regarded as a point light source in an optical system. For example, a semiconductor light emitting element 5 such as an LED is used, and brightness and light distribution characteristics required for a vehicle headlamp. Are mounted on the board 3 in an appropriate number and in an appropriate arrangement. Furthermore, the substrate 3 on which the light emitting element 5 is mounted is mounted on a metal plate 4, and the metal plate 4 on which the substrate 3 is mounted is attached to a heat sink 50.

  As a result, heat generated when the light emitting element 5 is turned on is conducted to the heat sink 50 through the substrate 3 and the metal plate 4 and dissipated from the heat sink 50 to the outside, and the temperature rise of the light emitting element 5 is suppressed. As a result, a decrease in light emission efficiency due to a temperature increase due to self-heating when the light emitting element 5 is turned on is suppressed, and a necessary amount of irradiation light can be reliably ensured.

  The reflector 10 includes two spheroidal curved surfaces, each composed of a spheroidal surface or a similar free-rotating curved surface, which are connected to each other with the position of the light source 2 as a common first focus f1. It has a compound ellipsoid consisting of a part located on one side (upper side) when divided vertically on a horizontal plane including the major axis of the curved surface, and each compound ellipsoid mainly reflects the one spheroid curved surface. The composite ellipsoidal reflecting surface 11 having the surface 11a and the other spheroidal curved surface as the subreflecting surface 11b is provided, and the rear end portion of the subreflecting surface 11b extending in the forward direction is connected to the front end portion of the main reflecting surface 11a. Has been.

  The reflector 10 is fixed to the heat sink 50 and is positioned so that the composite elliptical reflecting surface 11 covers the light source 2 from above.

The projection lens 30 is a plano-convex aspherical lens having a convex front surface (light emitting surface 30b) and a rear surface (light incident surface 30a), and the optical axis _XL is the main reflecting surface 11a. Along with the long axis, the rear focal point f3 is disposed so as to coincide with the second focal point f2a of the main reflecting surface 11a.

  The projection lens 30 is supported by a ring-shaped portion of the lens holder 40 that is fixed to the heat sink 50 and extends in a substantially cylindrical shape in the forward direction. The inside of the substantially cylindrical portion of the lens holder 40 is a space area for forming an optical path from the light emitted from the light source 2 to the projection lens 30.

  The movable mirror 20 is located between the light source 2 and the projection lens 30, and the upper surface (the surface on the composite elliptical reflecting surface 11 side) is a planar reflecting surface 20 a, and the front edge is curved in a concave shape on the rear side and the rear end It has a flat shape having a rotation support portion 20b on the edge side, and is rotatably arranged with the rotation support portion 20b as a fulcrum.

  The position of the movable mirror 20 is set in advance as the position for forming the low-beam light distribution pattern and the position for forming the high-beam light distribution pattern. Thus, the rotation support portion 20b that rotates around the rotation support shaft 61 positioned in the vehicle width direction is used as a fulcrum to switch to any position.

Among them, the case of forming a light distribution pattern for low beam, as shown in FIG. 2, the flat reflective surface 20a of the movable mirror 20 is positioned on the horizontal plane including the optical axis X _L, opposite its pivot support portion 20b The shared position of the second focal point f2a of the main reflecting surface 11a and the focal point f3 of the projection lens 30 is located in the vicinity of the end of the projection lens 30.

On the other hand, when forming a high beam light distribution pattern, as shown in FIG. 4, it is inclined downward toward the front at a predetermined angle plane reflecting surfaces 20a of the movable mirror 20 is with respect to the horizontal plane including the optical axis X _L So that the position of the second focal point f2b of the sub-reflecting surface 11b and the position of the second focal point f2a of the main reflecting surface 11a are located in a plane-symmetrical position with the plane reflecting surface 20a as a symmetric surface. It has become.

That is, the second focal point f2b of the sub-reflecting surface 11b are and located below the optical axis X _L between the back focal f3 after the first focal point f1 and the movable mirror 20 of the main reflecting surface 11a.

Incidentally, in the vehicle headlamp having such a structure, the light source 2 comprising a light-emitting element 5, the direction of the light-emitting axis X _S direction perpendicular Z of the optical axis X _L, of the main reflecting surface 11a It is slightly tilted forward so as to face the sub-reflecting surface 11b located on the front side. It is preferable that specific inclination angle α with respect to the vertical direction Z to the optical axis X _L of the light-emitting axis X _S of this time, in the range of about 10 to 20 °.

Thus, light-emitting axis X _S of the light source 2 will be located in the direction of the sub-reflecting surface 11b nearer when in the upward direction, aim the light intensity increases in emitted light toward the light source 2 to the secondary reflecting surface 11b be able to. Therefore, the illumination intensity of the irradiation area of the light distribution pattern that forms the reflected light from the sub-reflecting surface 11b as the irradiation light is increased.

  Next, the respective optical systems at the time of forming the light distribution pattern for the low beam and the light distribution pattern for the high beam in the above-described vehicle headlamp will be described with reference to FIGS.

First, at the time of forming the low beam light distribution pattern, as shown in FIG. 5, the rotation support portion 20 b of the movable mirror 20 is rotated around the rotation support shaft 61 via the rotation mechanism portion 60. the movable mirror 20 as a fulcrum pivot support portion 20b, a plane reflective surface 20a of the movable mirror 20 is positioned on the horizontal plane including the optical axis X _L Te.

Then, among the light emitted from the light source 2 located first near one focal point f1 of the main reflecting surface 11a, it is reflected toward the front of the optical axis X _L toward the main reflection surface 11a toward the main reflection surface 11a The light is divided into light that goes directly to the second focus f2a and light that goes to the plane reflecting surface 20a near the second focus, and the light that goes directly to the second focus f2a once converges at the second focus f2a and then diverges, The divergent light is projected onto the light incident surface 30a of the projection lens 30, guided through the projection lens 30, and irradiated from the light emitting surface 30b in the irradiation direction. The light traveling toward the planar reflecting surface 20a near the second focal point f2a is reflected by the planar reflecting surface 20a, and the reflected light converges at the second focal point f2a and then diverges. Similarly, the divergent light is emitted from the projection lens 30. The light is projected onto the incident surface 30a, guided through the projection lens 30, and irradiated from the light exit surface 30b in the irradiation direction.

  At this time, in the light distribution pattern formed by the irradiation light from the projection lens 30, as shown in FIG. 7, the inverted projection image of the front edge of the movable mirror 20 forms a cut-off line CL, and is reflected from the main reflection surface 11a. A pattern on the lower side of the cut-off line CL is formed by the reverse projection image of the light, and a hot zone is formed by the reflected light from the planar reflecting surface 11a. This light distribution pattern is a low beam light distribution pattern.

On the other hand, the light reflected downward of the optical axis X _L by sub reflective surface 11b toward the secondary reflective surface 11b located in front of the continuously to the main reflection surface 11a main reflection surface 11a, the optical axis again reflected by the reflecting surface 20a which is located on the horizontal plane including the X _L returns to the secondary reflecting surface 11b side.

  Therefore, the reflected light from the sub-reflecting surface 11b is not projected onto the projection lens 30 and does not affect the formation of the low beam light distribution pattern.

On the other hand, at the time of forming the high beam light distribution pattern, as shown in FIG. 6, the rotation support portion 20 b of the movable mirror 20 is rotated around the rotation support shaft 61 via the rotation mechanism portion 60. tilting fulcrum movable mirror 20 is a pivot support portion 20b, downwardly toward the front flat reflective surface 20a of the movable mirror 20 at a predetermined angle with respect to the horizontal plane including the optical axis X _L (direction away from the horizontal plane) Te It is located in the state that was allowed to.

  At this time, the specific position of the planar reflecting surface 20a of the movable mirror 20 is as described above, and the position of the second focal point f2b of the sub-reflecting surface 11b and the main reflecting surface 11a when the planar reflecting surface 20a is a symmetrical surface. The position of the second focal point f2a is set to a position that is plane symmetric.

Therefore, among the light emitted from the light source 2 located first near one focal point f1 of the main reflecting surface 11a, it is reflected toward the front direction of the optical axis X _L toward the main reflection surface 11a toward the main reflection surface 11a The light once converges at the second focal point f2a and then diverges, and the divergent light is projected onto the light incident surface 30a of the projection lens 30 and guided through the projection lens 30 toward the irradiation direction from the light exit surface 30b. Is irradiated.

  In the light distribution pattern formed by this irradiation light, the reflected light from the main reflecting surface 11a is projected as it is onto the projection lens 30 through the second focal point f2a without being shielded by the movable mirror 20, and by the inverted projection image. A light distribution pattern is formed. Therefore, a light distribution pattern that spreads greatly on both the upper side (U side) and the lower side (D side) of the horizontal reference line H as shown in FIG.

On the other hand, the light reflected downward of the optical axis X _L by sub reflective surface 11b toward the secondary reflective surface 11b which is positioned in a forward direction of the main reflecting surface 11a is provided continuously to the main reflection surface 11a, the light It is reflected by the flat reflective surface 20a which is inclined downward (away from the horizontal plane) toward the front at a predetermined angle with respect to the horizontal plane including the axis X _L, the sub-reflecting surface 11b of the flat reflective surface 20a and the plane of symmetry The second focal point f2b of the second focal point f2b is temporarily converged on the second focal point f2a and then diverges, and the diverging light is projected onto the light incident surface 30a of the projection lens 30 and guided through the projection lens 30. Then, the light is emitted from the light emitting surface 30b in the irradiation direction.

  In the light distribution pattern formed by the irradiation light, the primary reflected light reflected by the sub-reflecting surface 11b is further reflected by the planar reflecting surface 20a of the movable mirror 20, and the secondary reflected light passes through the second focal point f2a. The light is projected onto the projection lens 30 and a light distribution pattern is formed by the inverted projection image. Therefore, as shown in FIG. 8B, a light distribution pattern having a large irradiation light amount in a narrow range on both the upper side (U side) and the lower side (D side) of the horizontal reference line H is obtained.

  The two light distribution patterns are superimposed to form a high beam light distribution pattern shown in FIG. As can be seen from FIG. 8C, irradiation is performed in a narrow range both on the upper side (U side) and the lower side (D side) of the horizontal reference line H formed by the reflected light reflected by the sub-reflecting surface 11b. The light distribution pattern having a large amount of light forms a hot zone in the light distribution pattern for high beam, and thereby it is possible to ensure good far visibility.

Meanwhile, the effect on the formation of a light distribution pattern for high beam by the light source 2 to the arrangement of tilting the light-emitting axis X _S forward and described with reference to FIGS. It is assumed that a light emitting element 5 constituting the light source 2 has a substantially spherical directivity characteristic. In the figure, represents the directivity characteristics when the light emitting element 5 light-emitting axis X _S is arranged so that the upward (Z direction) the (D1) by dotted lines, the light emitting axis X _S angle α is forward from the upward (Z direction) The directivity (D2) when arranged so as to be inclined is represented by a solid line. The solid angle at which the light source 2 looks at the main reflecting surface 11a is β1, and the solid angle at which the light reflecting surface 11b looks at the sub-reflecting surface 11b is β2.

  Note that the sizes of the main reflection surface and the sub-reflection surface are set so that the solid angle β1 at which the light source expects the main reflection surface is larger than the solid angle β2 at which the sub-reflection surface is expected. Thereby, the entire region of the light distribution pattern is formed by the reflected light from the main reflection surface, and a hot zone is formed in a partial region of the light distribution pattern by the reflected light from the sub-reflection surface.

Therefore, each of the solid angle .beta.1, the area of oriented patterns are cut at .beta.2, Comparing the case where the inclined forward direction to the upward direction in the case where light-emitting axis X _S is at the upward side facing, stereoscopic As for the area cut out at the angle β1, as shown in FIG. 9, the area indicated by A of the directivity (D1) represented by the dotted line is represented by B of the directivity (D2) represented by the solid line. Larger than the marked area.

That is, when the light emitting axis _XS is upward, the area of the directivity pattern cut out at the solid angle β1 is larger than when the light emission axis XS is tilted forward, and it means that there is more light flux included in the solid angle β1. . Thus, the light distribution pattern (see FIG. 8A) formed by the reflected light from the main reflecting surface 11a is darker than when the light source 2 is directed upward by tilting the light source 2 forward. .

  On the other hand, as for the area cut out by the solid angle β2, as shown in FIG. 10, the area indicated by B of the directivity (D2) represented by the solid line has the directivity (D1) represented by the dotted line. It is larger than the area represented by A.

In other words, that the luminous axis X _S is larger the area of the directional patterns are cut in the solid angle β2 than when better when the inclined forward in the upward emission axis X _S is, the light beam contained in the solid angle β2 often Means. From this fact, than when the light distribution pattern formed by the light reflected from the auxiliary reflecting surface 11b (see FIG. 8 (b)), directed upward by inclining the orientation of the light-emitting axis X _S of the light source 2 to the front Will also be bright.

Thus, by arranging so as to tilt the light source 2 to the front light-emitting axis X _S upward and slightly, for the case of arranging the light source 2 so that the light emission axes X _S faces upward, emitted from the light source 2 The light directed toward the composite elliptical reflecting surface 11 is distributed to the main reflecting surface 11a and the sub-reflecting surface 11b, and the luminous intensity distribution of the light distribution pattern formed by the reflected light from each reflecting surface is optimized. As a result, a high beam light distribution pattern having a hot zone in which sufficient brightness is ensured as shown in FIG. 8C is realized, and a vehicular headlamp having good distant visibility can be realized. .

  As described above, the vehicular headlamp according to the present invention includes a main reflection surface and a sub-reflection surface that share a light source as a first focal point so as to cover a light source whose light emission axis is inclined upward and forward. A projection lens with the major axis of the main reflecting surface as the optical axis and the rear focal point positioned at the same position as the second focal point of the main reflecting surface, and the upper surface is a planar reflecting surface between the light source and the projection lens. In addition, a movable mirror is arranged in which the rotation support portion is positioned near the optical axis and the front end edge side extending forward from the rotation support portion is switched to either a position along the optical axis or a position inclined below the optical axis. Was established.

  When the low beam (passing beam) light distribution pattern is formed, the plane reflecting surface of the movable mirror is set at a position along the optical axis. Then, the light emitted from the light source in the direction of the main reflection surface is reflected by the main reflection surface, and the rear focal point of the projection lens is located at the same position as the second focal point of the main reflection surface and the second focal point. Then, the light is projected onto the projection lens and irradiated outside through the projection lens.

  On the other hand, when the high beam (running beam) light distribution pattern is formed, the plane reflecting surface of the movable mirror is set at a position inclined downward from the optical axis. At this time, the second focal point of the sub-reflecting surface is located below the planar reflecting surface, and the planar reflecting surface is symmetrical with respect to the rear focal point of the projection lens that is at the same position as the second focal point of the main reflecting surface. It is in a plane symmetrical position. Therefore, of the light emitted from the light source, the light directed toward the main reflection surface is reflected by the main reflection surface and is located at the same position as the second focal point of the main reflection surface and the second focal point. The light is projected onto the projection lens through the side focal point, and irradiated outside through the projection lens. The light traveling toward the sub-reflecting surface is reflected by the sub-reflecting surface, and the reflected light travels toward the second focal point of the sub-reflecting surface. It goes to the side focal point, passes through the rear side focal point, is projected onto the projection lens, and is irradiated to the outside through the projection lens.

  As described above, when the high beam distribution pattern is formed, the light emitted from the light source having the light emitting axis directed to the sub-reflecting surface side sequentially, the sub-reflecting surface, the plane reflecting surface of the movable mirror, the rear focal point of the projection lens, and An optical system related to the formation of an optical path irradiated outside through the projection lens is configured.

  Then, the light emitted from the light source arranged with the emission axis facing the sub-reflecting surface side irradiates through the optical system forms a hot zone in the high beam light distribution pattern. It will greatly contribute to the increase in luminous intensity.

  Also, by setting the light quantity ratio of the light emitted from the light source toward the main reflection surface and the light toward the sub-reflection surface to an appropriate ratio, a low beam light distribution pattern formed only by the reflected light of the main reflection surface, The balance of brightness between the light distribution pattern for high beam formed by the reflected light of the main reflecting surface and the reflected light of the sub-reflecting surface can be set to an optimum state.

  Note that the ratio of the amount of light from the light source toward the main reflection surface and the light toward the sub reflection surface can be set by changing the direction of the light emission axis of the light source or by the solid angle where the light source expects the main reflection surface and the solid reflection surface. This can be achieved by changing the corner ratio.

  As a result, both the low beam light distribution pattern and the high beam light distribution pattern can have good visibility, and the forward confirmation during night driving can be ensured.

  In addition, the rotation mechanism part in the above-mentioned description will not be specifically limited if it has a mechanism which rotates a movable mirror to a predetermined position.

DESCRIPTION OF SYMBOLS 1 ... Light source module 2 ... Light source 3 ... Board | substrate 4 ... Metal plate 5 ... Light emitting element 10 ... Reflector 11 ... Composite ellipsoidal reflective surface 11a ... Main reflective surface 11b ... Sub reflective surface 20 ... Movable mirror 20a ... Planar reflective surface 20b ... Time Motion support portion 30 ... Projection lens 30a ... Light incident surface 30b ... Light exit surface 40 ... Lens holder 50 ... Heat sink 60 ... Rotation mechanism portion 61 ... Rotation support shaft

Claims (2)

Two spheroidal curved surfaces, each consisting of a spheroidal surface or a similar free-rotating curved surface that share the first focal point position, are moved up and down on a plane including the major axis of the one spheroidal curved surface. The main reflecting surface formed on the one spheroid curved surface located substantially above when divided and the sub-reflecting surface formed on the other spheroid curved surface and at the front end of the main reflecting surface A composite elliptical reflecting surface formed by connecting rear end portions of the sub-reflecting surface, a light source located near the first focal point and having its emission axis directed upward and forward, and the light having the major axis as the optical axis. A projection lens whose rear focal point is located at the same position as the second focal point of the main reflecting surface on the axis, and is positioned between the light source and the projection lens, and the upper surface is a plane reflecting surface and is rotated to the rear edge side. It has a support part, and the front end edge side can be turned up and down with the turning support part as a fulcrum. A mirror, a vehicle headlamp equipped with,
When the plane reflecting surface of the movable mirror is in the vicinity of the optical axis and along the optical axis, the front edge of the movable mirror is positioned in the vicinity of the rear focal point of the projection lens and is emitted from the light source. The light reflected by the main reflecting surface is irradiated to the outside through the projection lens through the rear focal point,
When the reflecting surface of the movable mirror is at a position inclined downward with a predetermined angle with respect to the optical axis, the second focal point of the sub-reflecting surface located below the reflecting surface is The light emitted from the light source and reflected by the main reflection surface is located through the projection lens through the projection lens, in a plane-symmetric position with the plane reflection surface as a symmetry surface with respect to the rear focus. The primary reflected light reflected by the sub-reflecting surface is reflected again by the planar reflecting surface, and the secondary reflected light passes through the rear focal point to the outside through the projection lens. A vehicle headlamp characterized by being irradiated.   The vehicle headlamp according to claim 1, wherein a solid angle at which the light source looks at the main reflection surface is larger than a solid angle at which the sub-reflection surface is expected.

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