DE102007049361B4 - vehicle headlights - Google Patents

Abstract

A vehicle headlamp (2) comprising a light source (3), a lens (5) and an optical element (1), the lens (5) being pivotable about a substantially vertical axis (6) between the lens (5) and the lens at least one light source (3) the at least partially total reflecting optical element (1) is arranged, characterized in that in the optical element (1) via a light input surface (1a) light from the at least one light source (3) is coupled, and wherein the coupled light is coupled out of the optical element (1) via a light output surface (1b) and emitted by the lens (5) into an area in front of the vehicle headlight (2), and wherein the light output surface (1b) of the optical element (1) is above the optical axis (1). 4) of the lens (5) is arranged, and wherein the light outcoupling surface (1b) of the optical element (1) in horizontal sections at least on one side of the vertical plane (11) through the optical axis (4) of the lens (5) e a concavely curved curve (12), wherein the curvature of the curve (12) substantially corresponds to the field curvature or the focal line of the lens (5) in a predeterminable pivoted position of the lens.

Description

The invention relates to a vehicle headlamp, wherein the vehicle headlamp comprises at least one light source and a lens, wherein between the lens and the at least one light source, an at least partially totally reflecting optical element is arranged, in which light is coupled from the at least one light source via a light coupling surface, and wherein the coupled-in light is coupled out of the optical element via a light outcoupling surface and emitted by the lens into a region located in front of the vehicle headlight, and wherein the light outcoupling surface of the optical element is arranged above the optical axis of the lens, wherein the light outcoupling surface of the optical element in horizontal sections at least on one side the vertical plane through the optical axis of the lens is a concave curved curve.

In such vehicle headlights, the light is directed by one or more light sources through an at least partially totally reflecting optical element on a lens and radiated therefrom in the outer space. The optical element has a typically planar, but possibly also other designed coupling surface for light from the / the light source (s).

The decoupling surface is a usually flat surface through which the light is decoupled from the optical element.

The arrangement of the light source and the optical element above the optical axis of the lens is achieved that the light image is lowered relative to a horizontal, so that the legal requirements are met and dazzling oncoming traffic is avoided.

In the case of vehicle headlights with a fixed lens, in particular with lenses with a small focal length (about 25 mm), the problem arises that light is scattered in an area above the legally prescribed light-dark line, which can lead to dazzling oncoming traffic. For this reason, additional measures, such as Apertures necessary to hide these disturbing rays of light from the photograph.

For the generation of cornering light in vehicles, it is provided in certain solutions, that the lens - these are usually lenses with a flat surface and an aspheric surface, usually the aspherical surface is rotationally symmetric with respect to the optical axis of the lens - Is pivoted about a substantially vertical axis. In this way, the light image can be mitverschwenkt according to the curve.

However, it has been found that with a pivoting of such typical lenses in an arrangement described above in the low beam operation light reaches a range above the legally prescribed light-dark line (HD line). This effect is disadvantageous, above all, in the case of a bend in the direction of the driver's side - i. in a left-hander right-hand-traffic headlamp and vice versa - noticeable, since on the driver's side for the cut-off line a substantially horizontal branch is prescribed, which is approximately 0.57 ° below the horizontal. It comes through the pivoting of the lens to a tilting particular of the driver side branch of the cut-off line up.

The EP 1 357 333 A2 shows an optical element as mentioned above for a light unit with a fixed lens. This optical element can be used to solve the problems with respect to the legal requirements for the photograph for a fixed lens.

Due to the design of the decoupling surface of the optical element, it is not necessary to attach additional components such as screens, etc. for shielding of disturbing light rays in the headlight.

Those rays which would otherwise enter a lower region of the lens of the vehicle headlight and would then be emitted upward into an area above the permissible HD line are deflected upward in the decoupling surface shown, pass through the lens in an upper region and are deflected by this down to an area below the HD line.

DE 10 2005 005 562 A1 describes a vehicle headlight for cornering light, which in addition to a pivotable lens has an optical element, which is designed as a reflector. With this vehicle headlight to negative effects or a possible glare when pivoting the beam path or a lens of the vehicle headlight are eliminated.

It is an object of the invention to modify a vehicle headlight described above in such a way that the legal requirements for the light image are met even when pivoting the lens to generate a cornering light.

This object is achieved with a vehicle headlamp mentioned above in that the curvature of the curve substantially corresponds to the field curvature or the focal line of the lens in a predefinable pivoted position of the lens, preferably in the maximum laterally pivoted position of the lens.

With this embodiment of the light output surface, an optimal light image is achieved even with a pivoted lens.

In principle, it is sufficient if the decoupling surface has a modification according to the invention only on one side of the vertical plane through the optical axis, and on the other side the decoupling surface is flat, for example. In this way, the glare of oncoming traffic can be reliably prevented. In a dipped-beam vehicle headlamp for right-hand traffic, for example, modification of the right-hand side of the light outcoupling surface is basically sufficient.

It is, however, particularly advantageous if the decoupling surface is a concavely curved curve on both sides of the vertical plane through the optical axis of the lens. As a result, a dipped-beam headlamp for both right and left traffic is usable and also dazzling the traffic on the passenger side can be avoided. In addition, such a double-sided modification of fog lights is necessary.

In a specific embodiment of the invention, the decoupling surface is limited over its entire vertical extent of identically curved, superimposed curves. Accordingly, the light outcoupling surface is an area which has a concave curvature in the horizontal direction but no curvature in the vertical direction. A curvature in the vertical direction is not necessary, but may be favorable in special cases.

• 1 eine schematische Darstellung eines erfindungsgemäßen Fahrzeugscheinwerfers,
• 2 eine Detailansicht eines Optikelementes auf einem LED -Modul,
• 3 ausgewählte Strahlen bei einem erfindungsgemäßen Fahrzeugscheinwerfer in einem Vertikalschnitt durch die optische Achse der Linse,
• 4 ausgewählte Strahlen bei einem Fahrzeugscheinwerfer mit einem herkömmlichen Optikelement in einem Vertikalschnitt durch die optische Achse der Linse,
• 5 eine Draufsicht auf einen erfindungsgemäßen Fahrzeugscheinwerfer ohne Gehäuse, 6 eine Vorderansicht eines LED-Moduls mit davor angebrachtem Optikelement,
• 7 eine schematische Darstellung der Schnittkurve zwischen der Horizontalebene durch den Linsenmittelpunkt und der meridionalen Bildschale der Linse und
• 8 eine schematische Darstellung der Konstruktion der meridionalen Bildschale einer Linse.

In the following the invention is explained in more detail with reference to the drawing. In this shows

• 1 a schematic representation of a vehicle headlight according to the invention,
• 2 a detailed view of an optical element on an LED module,
• 3 Selected beams in a vehicle headlamp according to the invention in a vertical section through the optical axis of the lens,
• 4 selected beams in a vehicle headlamp with a conventional optical element in a vertical section through the optical axis of the lens,
• 5 a plan view of a vehicle headlight according to the invention without housing, 6 a front view of an LED module with an attached optical element,
• 7 a schematic representation of the intersection curve between the horizontal plane through the lens center and the meridional image shell of the lens and
• 8th a schematic representation of the construction of the meridional image shell of a lens.

1 schematically shows a vehicle headlight according to the invention 2 , with a light source 3 and a lens 5 , The example shown is a headlight 2 for cornering light, where the lens 5 around a vertical axis 6 is pivotable to the left and right. At the light source 3 In this example, this is one or more light-emitting diodes which are mounted on a corresponding LED printed circuit board 7 are arranged.

The vehicle headlight 2 is shown in installation position in a vehicle.

Between the lens 5 and the light source 3 is an at least partially totally reflective optical element 1 arranged, in which via a light input surface 1a Light from the light source 3 is coupled. The coupled light couples via a light output surface 1b from the optic element 1 out and gets through the lens 5 in front of the vehicle headlight 2 lying area radiated. The light output surface 1b of the optical element 1 is above the optical axis 4 the lens 5 arranged so that a corresponding lowered below the horizontal light image is achieved.

In the example shown, the light source is also 3 above the optical axis 4 the lens 5 arranged, however, this can also be below or the same height of the optical axis 4 when it is ensured that the light output surface 1b above the optical axis 4 lies.

5 shows the headlight according to the invention 2 still in a plan view, 6 shows a front view of the optical element 1 ,

3 and 4 show a vehicle headlight 2 in a side view, wherein the vehicle headlights in 3 via an optical element according to the invention 1 with a light output surface 1b features while the headlight 2 out 4 via a conventional optical element 1' with a conventional, flat light output surface 1b ' features, with this flat surface 1b ' normal to the optical axis 4 the lens 5 stands.

According to the invention, the light output surface 1b of the optical element 1 in horizontal sections at least on one side of the vertical plane 11 through the optical axis 4 the lens 5 a concave curved curve 12 (please refer 1 and 5 ), in the embodiment shown, the curvature on both sides of the vertical plane 11 is provided.

In the illustrated embodiment of the invention, the decoupling surface 1b over the entire vertical extent of identically curved, superimposed curves 12 limited. Accordingly, it is in the light output surface 1b around a surface, which in the horizontal direction has a concave curvature, in the vertical direction but no curvature.

Due to the inventive design of the decoupling surface 1b become those rays, which at unmodified decoupling surface 1b ' in a lower area of the lens 5 of the vehicle headlight and would then be emitted from there upwards in an area above the permissible HD line, deflected upward, occur in an upper region through the lens 5 and are deflected by this down to an area below the HD line, as evidenced by 1 . 3 and 4 is explained in more detail below.

How 1 shows results in a section of the optical element with a vertical plane 8th a first point 9 at the light output surface 1b at the bottom of the optical element 1 ( 3 ). The vertical plane 8th is at an angle not equal to zero to the optical axis 4 of the optical element inclined and intersects the contour of the light output surface outside the piercing point of the optical axis 4 through the light output surface.

Furthermore, one is in the opticsement 1 lying point 10 to recognize ( 3 ). This point 10 lies with a conventional optical element 1' (Which otherwise has identical dimensions as the optical element according to the invention 1 ) as in 4 shown on the light output surface 1b ' while the point 9 in this conventional optical element 1b ' already outside and in front of the visual element 1' lies.

Looking now 4 , one recognizes that a ray passes through the point 9 straight from the optic element 1' exit (solid line), in a lower area on the lens 5 meets and emerges from this essentially horizontal. This also applies to all other rays that are seen in the direction of the lens in front of the point 9 lie.

All the rays between the point 10 (dashed line) and the (fictitious) point 9 pass through (intervening beam is shown as a dotted line), also occur in a lower area through the lens 5 and are broken up, into an area above the HD line.

By the curvature of the invention in an optical element 1 as in 3 Now all the rays that appear between the points are represented 9 and 10 coming from the inside on the bottom of the optics element 1 impinge, totally reflected and reflected upwards, allowing them into an upper area of the lens 5 from where they go down and under the HD line.

The effect according to the invention is with a lens 5 qualitatively discussed in straight position Actually, the above effects occur especially when the lens is pivoted from the straight position, so in a headlight for cornering, or when straightening the lens 5 if it has a small focal length.

In a fixed lens, an optimal light image is achieved when the curvature of the curve 12 the field curvature or the focal line of the lens 5 in the zero position corresponds.

In the case of a vehicle headlight 2 for cornering light as shown, in which the lens 5 around a substantially vertical axis 6 , which is arranged in the vicinity of the light outcoupling surface or is in this, is pivotable, an optimal light image is then obtained even when the lens pivoted, when the curvature of the curve substantially the field curvature or the focal line of the lens 5 in a predeterminable pivoted position of the lens, preferably in the maximum laterally pivoted position of the lens 5 , corresponds.

The term of the focal line of a lens and the field curvature is in 7 and 8th briefly explained. The focal line is the intersection curve between the horizontal plane through the lens center and the meridional image shell. The meridional image shell is in 8th The rays of point P, which are in the meridional plane (spanned across points P . D . M1 ) break through the lens, focus in the spot bm , Will the point P moved, the corresponding point shifts bm , All the points thus formed bm lie on a surface - this is referred to as "meridional image shell" or field curvature.

Claims (4)

A vehicle headlamp (2) comprising a light source (3), a lens (5) and an optical element (1), the lens (5) being pivotable about a substantially vertical axis (6) between the lens (5) and the lens at least one light source (3) the at least partially total reflecting optical element (1) is arranged, characterized in that in the optical element (1) via a light input surface (1a) light from the at least one light source (3) is coupled, and wherein the coupled light via a light output surface (1b) from the optical element (1) coupled and from the lens (5) in a light emission area (1b) of the optical element (1) above the optical axis (4) of the lens (5) is arranged, and wherein the light outcoupling surface (1b) of the optical element (1 ) in horizontal sections at least on one side of the vertical plane (11) through the optical axis (4) of the lens (5) is a concavely curved curve (12), wherein the curvature of the curve (12) is substantially the field curvature or the focal line of the lens (5) corresponds in a predetermined pivotal position of the lens. Vehicle headlights after Claim 1 , characterized in that the light output surface (1b) on both sides of the vertical plane (11) through the optical axis (4) of the lens (5) is a concave curved curve (12). Vehicle headlights after Claim 1 or 2 , characterized in that the light output surface (1b) over its entire vertical extent of identically curved, superimposed curves (12) is limited. Vehicle headlight according to one of the preceding claims, characterized in that the curvature of the curve (12) substantially corresponds to the field curvature or the focal line of the lens (5) in the maximum laterally pivoted position of the lens (5).

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