JP2007323839A - Vehicular lighting fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a conventional vehicular lighting fixture may give rise to visual discomfort to drivers in some cases, and to prevent uneven distribution of light. <P>SOLUTION: A sub-reflecting surface 11 forms a downward-inclined surface having no step in an entire region from a semiconductor light source 6 to a second focal point F2 of a main reflecting surface 4 or the vicinity thereof. Consequently, it is possible to prevent, with reliability, the occurrence of uneven light distribution for a predetermined sub-light distribution pattern formed by light reflected from the sub-reflecting surface 11 having no step in its entirety. This eliminates the possibility of giving rise to any visual discomfort to drivers, and thus contributes to traffic safety. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projector-type vehicular lamp that uses a semiconductor-type light source such as an LED as a light source.

  This type of vehicular lamp is conventionally known (for example, Patent Document 1). Hereinafter, the vehicle lamp will be described. A conventional vehicular lamp is one in which LED light as a light source is reflected by a reflector and then emitted forward through a convex lens. The reflector includes a main reflector having a first reflecting surface based on an ellipse, and a sub-reflector having a shade function having a second reflecting surface which is disposed between the convex lens and the LED and is substantially flat with the optical axis. And is composed of. A predetermined main light distribution pattern is formed by the shade function of the sub-reflector from the reflected light from the first reflecting surface, and a predetermined sub-light distribution pattern is formed by the reflected light from the second reflecting surface. Thereby, the conventional vehicle lamp can obtain a light distribution pattern in which a predetermined main light distribution pattern and a predetermined sub light distribution pattern are combined, for example, a passing light distribution pattern shown in FIG. FIG. 7 is an explanatory diagram of a light distribution pattern on the screen showing an isoilluminance curve. The illuminance increases from the outer curve to the inner (center) curve.

  However, in the conventional vehicular lamp, a step 101 is formed at the center of the second reflecting surface provided in the sub-reflector 100 as shown in FIGS. That is, the second reflecting surface is formed of the central step portion 101, the high-level reflecting surface 102 that is substantially horizontal HH, and the low-level reflecting surface 103 that is inclined by θ °. For this reason, in the conventional vehicular lamp, uneven distribution of light occurs in a predetermined sub-light distribution pattern formed by reflected light from the second reflecting surface by the central step portion 101 of the second reflecting surface. As a result, the conventional vehicular lamp has a concave portion at the lower center of the innermost curve in the lower part of the elbow point of the passing light distribution pattern shown in FIG. 7 (the part surrounded by the dotted ellipse in FIG. 7). And a dark zone D (see the hatched portion in FIG. 7) is generated in the concave portion. As a result, the conventional vehicular lamp may give the driver a visual discomfort due to non-uniform light distribution in the dark zone D that occurs in a portion from just before the vehicle to the front.

JP 2006-107955 A

  The problem to be solved by the present invention is that the conventional vehicular lamp may give the driver a visual discomfort.

  The present invention (the invention according to claim 1) is characterized in that the sub-reflecting surface forms an inclined surface having no step over the entire area from the semiconductor-type light source to the second focal point of the main reflecting surface or the vicinity thereof. To do.

  According to the present invention (the invention according to claim 2), the lens focal point of the projection lens is located at or near the second focal point of the main reflecting surface, and the second focal point of the main reflecting surface or the vicinity thereof in the shade is predetermined. A projection having an edge forming a cut-off line of the main light distribution pattern is provided along the lens focal point of the projection lens.

  This invention (the invention according to claim 3) is characterized in that the sub-reflector and the shade are provided integrally.

  The vehicular lamp according to the present invention (the invention according to claim 1) has uneven light distribution in a predetermined sub-light distribution pattern formed by the reflected light from the sub-reflecting surface by the sub-reflecting surface having no step throughout. Can be reliably prevented. As a result, in the vehicular lamp of the present invention (the invention according to claim 1), a dark zone is generated in a portion of the light distribution pattern in which the predetermined main light distribution pattern and the predetermined sub light distribution pattern are combined. Can be reliably prevented. As a result, the vehicular lamp according to the present invention (the invention according to claim 1) does not give the driver a visual discomfort due to non-uniform light distribution in the dark zone that occurs in a portion of the light distribution pattern. Can contribute to road safety.

  According to the vehicle lamp of the present invention (the invention according to claim 2), a cut-off line can be easily and reliably formed in a predetermined main light distribution pattern due to the problem to be solved by the invention.

  In the vehicular lamp of the present invention (the invention according to claim 3), since the sub-reflector and the shade are integrated, the number of parts can be reduced, and the manufacturing cost can be reduced correspondingly.

  Embodiments of a vehicular lamp according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In the drawing, reference sign “VU-VD” indicates vertical lines on the upper and lower sides of the screen. Reference sign “HL-HR” indicates horizontal lines on the left and right of the screen. The symbol “HH” indicates a horizontal line. The symbol “Z-Z” indicates the optical axis of the lamp unit (the optical axis of the main reflecting surface, the optical axis of the projection lens).

  Hereinafter, the configuration of the vehicular lamp in this embodiment will be described. In this example, for example, an automotive headlamp will be described. In FIG. 5, the code | symbol 1 is a vehicle lamp in this Example. As shown in FIG. 5, the vehicular lamp 1 is a projector type and has a unit structure. The vehicular lamp 1 includes an upper main reflector 2, a lower sub reflector 3, a semiconductor light source 6, a shade 5, a projection lens (convex lens, condenser lens) 7, and a vehicle headlight (not shown). A lamp housing and a lamp lens (for example, a transparent outer lens).

  The main reflector 2, the sub reflector 3, the semiconductor light source 6, the shade 5, and the projection lens 7 constitute a lamp unit. One or a plurality of the lamp units are arranged, for example, via an optical axis adjusting mechanism in a lamp chamber defined by a lamp housing and a lamp lens of an automotive headlamp.

  The main reflector 2 and the sub reflector 3 are made of a light-impermeable resin member or the like, and are also used as holding members such as a casing, a housing, and a holder. The main reflector 2 and the sub-reflector 3 are horizontally divided into two vertically along the optical axis ZZ. The main reflector 2 and the sub-reflector 3 are integrally fixed by fixing means (not shown) (for example, a bolt nut, a screw, caulking, a clip, etc.). The main reflector 2 and the sub reflector 3 may be formed integrally.

  The main reflector 2 has a front portion opened in a semicircular shape and is closed from the front portion to the rear portion through the central portion (upper portion). A main reflecting surface 4 is provided on the concave inner surface of the closed portion from the rear half to the rear portion of the central portion of the main reflector 2 by applying aluminum vapor deposition or silver coating.

  The main reflecting surface 4 is a reflecting surface based on an ellipse, such as a rotating ellipsoid or a free-form surface (NURBS surface) based on an ellipse (the vertical cross section of FIG. 5 is an ellipsoid, and A horizontal cross section (not shown) is a parabolic surface or a reflecting surface forming a deformed parabolic surface). For this purpose, the main reflecting surface 4 has a first focal point F1 and a second focal point (focal lines on the horizontal section, that is, both ends are located on the projection lens 7 side when viewed from above (plane), and the center is the semiconductor. Curved focal line F2 located on the mold light source 6 side.

  The sub-reflector 3 has a semicircular opening at the front side, the front part to the front part of the central part (lower part) is closed, and the rear part of the central part to the rear part is open. is doing. As shown in FIGS. 1 and 5, the closed portion of the sub-reflector 3 includes a front lower horizontal plate portion 8, an intermediate vertical plate portion 9, and a rear upper horizontal plate portion 10. On the upper surface of the upper horizontal plate portion 10 of the sub-reflector 3, aluminum vapor deposition or silver coating is applied, and a sub-reflecting surface 11 having a substantially flat surface along the optical axis ZZ is provided.

  As the semiconductor-type light source 6, for example, a self-luminous semiconductor-type light source (LED in this embodiment) such as LED or EL (organic EL) is used. The semiconductor light source 6 includes a substrate, a light emitting body of a light source chip (semiconductor chip) having a small rectangular shape (square shape) fixed to one surface of the substrate, and a light transmitting member that covers the light emitting body. Has been. The semiconductor light source 6 is held by the main reflector 2 and the sub-reflector 3. The light emitter (light emitting portion) of the semiconductor light source 6 is located at or near the first focal point F1 of the main reflective surface 4. The semiconductor light source 6 is disposed in the rear opening of the sub reflector 3.

  The shade 5 is provided integrally with the sub reflector 3. That is, the shade 5 is also used as the upper horizontal plate portion 10 of the sub reflector 3. The shade 5 is disposed between the semiconductor light source 6 and the second focal point F <b> 2 of the main reflecting surface 4 or the vicinity thereof. The shade 5 cuts off a part of the reflected light emitted from the semiconductor-type light source 6 and reflected by the main reflecting surface 4, and forms a predetermined main light distribution pattern with the remaining reflected light. It is.

  The projection lens 7 is held at the edge of the front semicircular opening of the main reflector 2 and the edge of the front semicircular opening of the sub-reflector 3. The projection lens 7 is an aspheric lens convex lens. The front side (external side) of the projection lens 7 has a convex aspheric surface with a large curvature (small curvature radius), while the rear side (the semiconductor light source 6 side) of the projection lens 7 has a small curvature. Convex aspherical surface (large curvature radius). By using such a projection lens 7, the focal length of the projection lens 7 is reduced, and accordingly, the dimension of the projection lens 7 of the vehicle lamp 1 in this embodiment is in the direction of the optical axis ZZ. It becomes compact. The rear side of the projection lens 7 may be a flat aspherical surface.

  The projection lens 7 has a front focus (focus on the semiconductor light source 6 side) and a rear focus (external focus), and an optical axis ZZ connecting the front focus and the rear focus. The optical axis ZZ of the main reflecting surface 4 and the optical axis ZZ of the projection lens 7 substantially coincide. The front focal point of the projection lens 7 is a lens focal point (meridional image plane that is a focal plane on the object space side) FL. The lens focal point FL of the projection lens 7 is located at or near the second focal point F2 of the main reflecting surface 4. In addition, since the light from the semiconductor light source 6 does not have high heat, a resin lens can be used as the projection lens 7. The projection lens 7 uses acrylic in this example. The projection lens 7 projects forward a predetermined sub light distribution pattern formed by the predetermined main light distribution pattern and the reflected light from the sub reflection surface 11.

  The sub-reflection surface 11 is provided between the second focal point F <b> 2 of the main reflection surface 4 or the vicinity thereof and the semiconductor light source 6. Further, as shown in FIGS. 2 and 3, the sub-reflecting surface 11 has a downward slope with no step from the semiconductor-type light source 6 to the second focal point F2 of the main reflecting surface 4 or the vicinity thereof. Make a face. That is, the sub-reflection surface 11 is inclined by θ ° (about 1 ° to 3 °) with respect to the horizontal line HH.

  Edges 12, 13 that form cut-off lines CL 1, CL 2, CL 3 and elbow point E of the predetermined main light distribution pattern at the second focal point F 2 of the main reflecting surface 4 or in the vicinity thereof in the shade 5. 14 is provided along the lens focal point FL of the projection lens 7. The protrusion 15 is integrally provided at a corner of the vertical plate 9 and the upper horizontal plate 10.

  The vehicular lamp 1 in this embodiment is configured as described above, and the operation thereof will be described below.

  First, the light emitter of the semiconductor light source 6 of the vehicular lamp 1 is turned on. Then, light L1 is emitted from the light emitter of the semiconductor light source 6. The light L1 is reflected by the main reflecting surface 4, and the reflected light L2 is concentrated on the second focal point F2 of the main reflecting surface 4. A part of the reflected light L2 concentrated on the second focal point F2 is cut off by the shade 5. The reflected light L2 cut off by the shade 5 is reflected by the sub-reflecting surface 11 which is integral with the shade 5 and forms a downwardly inclined surface having no step over the whole, and forms a predetermined sub-light distribution pattern. It is formed. On the other hand, a predetermined main light distribution pattern is formed by the remaining reflected light L2.

  The predetermined sub light distribution pattern and the predetermined main light distribution pattern are transmitted through the projection lens 7 and combined to form a predetermined light distribution pattern, for example, in front of the automobile (vehicle) as the passing light distribution pattern shown in FIG. Projected to illuminate the road surface.

  Cut-off lines CL1, CL2, CL3 and elbow points E are formed by the edges 12, 13, 14 of the shade 5 at the upper edge of the light distribution pattern for passing shown in FIG. This light distribution pattern for passing can illuminate roads on the driving lane side to the far or far distance by the upper horizontal cut-off line CL1, and the roads on the opposite lane side by the lower horizontal cut-off line CL3. Mainly the front side can be illuminated.

  The vehicular lamp 1 in this embodiment is configured and operated as described above, and the effects thereof will be described below.

  In the vehicular lamp 1 according to this embodiment, unevenness in light distribution occurs in a predetermined sub-light distribution pattern formed by the reflected light from the sub-reflecting surface 11 due to the sub-reflecting surface 11 having no step throughout. Can be reliably prevented. As a result, the vehicular lamp 1 according to this embodiment has a predetermined light distribution pattern in which a predetermined main light distribution pattern and a predetermined sub light distribution pattern are combined, for example, the passing light distribution pattern shown in FIG. In a certain part, in this example, a lower part of the elbow point (a part surrounded by a dotted ellipse in FIG. 6), it is possible to reliably prevent the dark zone from occurring.

  That is, the vehicular lamp 1 according to this embodiment, like a conventional vehicular lamp, is a lower portion of the elbow point of the passing light distribution pattern shown in FIG. 7 (portion surrounded by a dotted ellipse in FIG. 7). In FIG. 7, it is possible to reliably prevent the dark zone D (see the hatched portion in FIG. 7) from occurring in the recess formed at the center of the lower part of the innermost curve. As a result, the vehicular lamp 1 according to this embodiment contributes to traffic safety because it does not give the driver a visual discomfort due to non-uniform light distribution in the dark zone that occurs in a portion with a light distribution pattern. can do.

  Further, in the vehicular lamp 1 according to this embodiment, the lens focal point FL of the projection lens 7 is located at or near the second focal point F2 of the main reflecting surface 4, and the second focal point F2 of the main reflecting surface 4 of the shade 5 is provided. Alternatively, the protrusion 15 having the edges 12, 13, and 14 forming the cut-off lines CL1, CL2, and CL3 and the elbow point E of the predetermined main light distribution pattern is provided along the lens focal point FL of the projection lens 7 in the vicinity thereof. It is provided. For this reason, the vehicular lamp 1 according to this embodiment can easily and reliably form the cut-off lines CL1, CL2, CL3 and the elbow point E in a predetermined main light distribution pattern.

  Furthermore, since the vehicular lamp 1 according to this embodiment includes the sub-reflector 3 and the shade 5, the number of parts can be reduced, and the manufacturing cost can be reduced correspondingly.

  In addition, in the said Example, the headlamp for motor vehicles is demonstrated as a vehicle lamp. However, in the present invention, the vehicle lamp may be a lamp other than the automotive headlamp, for example, a rear combination lamp tail lamp, brake lamp, tail brake lamp, backup lamp, or the like.

It is a perspective view of the sub reflector which shows the Example of the vehicle lamp concerning this invention. Similarly, it is explanatory drawing of the II-II line cross section in FIG. Similarly, it is explanatory drawing of the III-III sectional view in FIG. Similarly, it is explanatory drawing of the IV-IV line cross section in FIG. Similarly, it is a longitudinal sectional view showing a lamp unit. Similarly, it is explanatory drawing of the light distribution pattern on a screen which shows the isoilluminance curve of a predetermined light distribution pattern. It is explanatory drawing of the light distribution pattern on a screen which shows the isoilluminance curve of the predetermined light distribution pattern by the conventional vehicle lamp. It is a perspective view which shows the sub reflector of the conventional vehicle lamp. Similarly, it is explanatory drawing of the IX-IX line cross section in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle lamp 2 Main reflector 3 Sub reflector 4 Main reflecting surface 5 Shade 6 Semiconductor type light source (LED)
7 Projection lens 8 Lower horizontal plate portion 9 Vertical plate portion 10 Upper horizontal plate portion 11 Sub reflection surface 12, 13, 14 Edge 15 Projection portion HL-HR Left and right horizontal lines VU-VD Upper and lower vertical lines HH Horizontal lines F1 Main reflection surface F2 Second focal point of main reflecting surface FL Lens focal point of projection lens ZZ Optical axis of lamp unit CL1, CL2, CL3 Cut-off line E Elbow point L1 Light emitted from semiconductor type light source L2 On main reflecting surface Reflected light

Claims (3)

In a projector-type vehicular lamp that uses a semiconductor-type light source as a light source,
A main reflector having a main reflecting surface based on an ellipse;
A sub-reflector having a sub-reflecting surface that is substantially flat along the optical axis;
The semiconductor-type light source disposed so that a light emitting unit is positioned at or near the first focal point of the main reflecting surface;
A part of the reflected light which is disposed between the second focal point of the main reflection surface or the vicinity thereof and the semiconductor-type light source and is radiated from the semiconductor-type light source and reflected by the main reflection surface is cut off. A shade that forms a predetermined main light distribution pattern with the remaining reflected light;
A projection lens that projects forward the predetermined sub light distribution pattern formed by the predetermined main light distribution pattern and the reflected light from the sub reflection surface;
With
The sub-reflecting surface is provided between the second focal point of the main reflecting surface or the vicinity thereof and the semiconductor-type light source, and extends from the semiconductor-type light source to the second focal point of the main reflecting surface or the vicinity thereof. It forms a slope with a downward slope that has no steps throughout.
A vehicular lamp characterized by the above. The lens focus of the projection lens is located at or near the second focus of the main reflecting surface,
A projection having an edge forming a cut-off line of the predetermined main light distribution pattern is provided along the lens focal point of the projection lens at the second focal point of the main reflecting surface or in the vicinity thereof in the shade. ing,
The vehicular lamp according to claim 1.   The vehicular lamp according to claim 1, wherein the sub-reflector and the shade are provided integrally.

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