EP0404990A1 - Motor vehicle light - Google Patents

Abstract

In order to achieve as high as possible a light intensity within prescribed limits in conjunction with a light distribution in which the light is horizontally widely scattered and vertically only slightly scattered, a motor vehicle light has a reflector (R) and/or a lens for focusing the light (S) emanating from a light source (LI), and an optical pane (O) which is inserted downstream in the beam path and has optically active elements which are arranged juxtaposed in rows. A prescribed number of elements are constructed as lenses, each lens being constructed as a concave or convex scattering lens having two scattering radii, and the vertical scattering radius being larger than the horizontal scattering radius of the scattering lenses. The remaining number of the elements are constructed as prisms, each prism being constructed as a horizontally and/or vertically acting prism. The optical pane (O) is coloured in this arrangement in colour which differs from the colour of the emitted light, a colour filter (F) being provided for the motor vehicle light. <IMAGE>

Description

The invention relates to a motor vehicle lamp for generating a predetermined light distribution with an outer optical disc, the color of which differs from the color of the emitted light.

From the German patent application DE-OS 17 55 770 a rear fog lamp for motor vehicles is known which has a reflector for focusing the light emerging from a light source, an optical disc being connected downstream in the beam path. The optical disk has optically active elements which are arranged adjacent to one another in rows. A predetermined number of optically active elements is designed as lenses that scatter the incident light. The other optically active elements are designed as prisms which have sawtooth-shaped cross sections in both a horizontal and a vertical plane in order to produce a uniform light distribution. The prisms ensure that the non-uniform light distribution generated by the honeycomb-like, rectangular lenses, which has very high light intensities in a central region and light intensities that decrease sharply towards the edge, is compensated for, so that a maximum permitted light intensity in the central region is not is exceeded.

Because the lenses and the prisms are combined into groups in fields, there is the disadvantage that a complex and expensive construction is required in particular for the formation of the prisms and that the tools for producing the optical disk are expensive to manufacture and to carry out and are complex since the adjoining prisms, which have horizontal and vertical angles, are clearly delimited from one another must be in order to achieve the desired optical effect. In this context, it has proven to be particularly disadvantageous that the tools for manufacturing the optical disk in order to comply with this predetermined condition may have only slight wear during the production process and therefore have to be replaced frequently and at high cost.

Another disadvantage is that the honeycomb-like, rectangular lenses, which can be convex or concave, can only illuminate a given base area very unevenly and with emphasis on the center, so that this light distribution generated by the lenses determines the deflection angle for the vertically and horizontally acting prisms .

In the motor vehicle lamp used here, which is designed as a rear fog lamp, the outer optical disk has a red color which corresponds to the color of the light emitted. If the outer lens is to be of a different color than that of the light emitted, the use of an additional color filter is required. With the light distribution that can be generated here, there is the disadvantage that, due to the reduction of the light intensity through the use of the color filter to about half the previously achievable light intensity, the prescribed and / or required light intensities cannot be met or achieved in a predetermined light distribution area without that the optical disk is enlarged or the nominal power of the light source is increased.

From the German patent DE-PS 10 99 408 a motor vehicle lamp is known which has a light source and an optical disc connected downstream in the beam path. The light collection and light distribution is carried out exclusively by the optically acting elements of the optics disc. The optically effective elements are here arranged next to each other in rows. All optically active elements are designed here as prisms, which act vertically and / or horizontally, so that the light emitted by the light source is directed by each prism in a predetermined direction. Any desired light distribution can be generated by such a configuration of the optical disk.

The disadvantage here is that the construction of such a lens is very complex and costly and that the tools for producing such a lens are expensive and subject to high wear during production. It proves to be particularly disadvantageous that if a reflector is omitted to concentrate the light from the light source, only low light intensities can be achieved for a given light distribution, so that, for. B. the use of such a motor vehicle lamp as a rear fog lamp is not possible. This applies in particular if the light emitted by the motor vehicle lamp is to have a different color than the color of the outer optical pane, since in such a case an additional color filter is required which reduces the achievable light intensity by about half.

From the German patent application DE-OS 34 20 175 a motor vehicle lamp is known in which the color of the emitted light differs from the color of the outer cover plate. This motor vehicle lamp has a light source and an optical disc, which is colorless. A color filter is arranged between the light source and the optical disk. The color filter is designed here, for example, like a dome or dome, so that it partially surrounds the light source. The optical disk here has prisms on the outer surface which are used to collect the light emerging from the light source. A colorless or color-neutral cover plate with a scattering optic creates the outer Appearance of the automotive lamp. In order to achieve the highest possible light efficiency, the color filter has a collecting optic that is matched to the collecting optics of the optical disk.

It proves to be disadvantageous that in addition to the optical lens, an additional cover lens is required, which increases the costs both for the design and for the manufacture of the motor vehicle lamp. It proves to be particularly disadvantageous that, in addition to the optical disk, the color filter and the cover disk are designed as optically effective elements which make it necessary for the optical effect of the light disks to be coordinated with one another, which results in a considerable construction effort and expensive production . In this context it proves to be particularly disadvantageous that a predetermined special light distribution with predetermined light intensities without the use of a light-concentrating reflector and a special design of the prisms, for. B. when using the motor vehicle lamp as a rear fog lamp, can not be achieved.

The invention has for its object to provide a motor vehicle lamp, the use of the smallest possible, the light distribution determining the outer optic disc, which is colored in a color that differs from the color of the emitted light, and when using a light source a normal nominal power ensures that a predetermined light distribution, in which the light is widely scattered horizontally and vertically only slightly and has a gain in a medium range, is achieved with the highest possible luminous intensity specified within limits.

This object is solved by the features of claim 1.

It is advantageous that a reflector and / or a lens is provided for bundling the light emerging from a light source, because thus the light from the light source is used as well as possible, thereby making it possible for the light source to have a customary nominal power.

The fact that the optical disk, which is connected downstream in the beam path, has optically active elements which are arranged adjacent to one another in rows results in the advantage of a simple and inexpensive construction and manufacturability of the optical disk which determines the light distribution.

It is particularly advantageous that a color filter is arranged in the beam path between the reflector and / or the lens for bundling the light and the optical disk and / or the beam path between the light source and the reflector or the lens for bundling the light, because it is very different Shapes and arrangements of the color filter are possible and in particular the position of the color filter relative to the optical disk can be freely selected, since the light distribution is determined by the optical disk. This also has the advantage that the motor vehicle lamp is simple and inexpensive to manufacture.

The fact that a predetermined number of elements is designed as lenses and each lens is designed as a concave or convex scattering lens with two scattering radii, which scatters the incident light onto a base surface arranged at a predetermined distance from the motor vehicle lamp, the advantage arises that Base area is illuminated as evenly as possible in all areas because each of the lenses illuminates the base area evenly due to the design as a diffusing lens with two diffusing radii.

It is advantageous that the vertical spreading radius is larger than the horizontal spreading radius of the spreading lenses, because thus is achieved that the incident light is scattered more in the horizontal direction than in the vertical direction, whereby a rectangular base is illuminated as evenly as possible.

It is advantageous that the remaining number of elements is designed as prisms, each prism being designed as a horizontally and / or vertically acting prism, which directs the incident light onto a given partial area of the base area, because that the partial areas of the base area which are illuminated by the prisms have a higher light intensity than the partial areas of the base area which are not illuminated by the prisms, as a result of which a predetermined light distribution with a light intensity which is predetermined within limits, i. H. a minimum light intensity and a maximum light intensity is also achieved if a color filter is connected upstream of the optical disc in the beam path, which reduces the light intensity by about half. If the motor vehicle lamp z. B. used as a rear fog lamp, which requires a high light intensity in a cruciform area of the base, which is more pronounced in the horizontal direction than in the vertical direction, can be achieved by illuminating this cruciform area through the prisms, the desired light distribution with the predetermined light intensity will.

It is advantageous that the optical disk is subdivided into a predetermined number of basic elements, that each basic element has the same predetermined sequence and number of prisms and lenses, and that each basic element generates an identical predetermined light distribution because the predetermined light distribution with the minimum light intensity and the the maximum permissible light intensity can be adhered to as precisely as possible, since the different light intensities and luminous fluxes can be achieved by the predefined configuration of the subject matter of the invention, in which each basic element generates the same predefined light distribution be balanced and averaged at different locations on the optical disk, which would not be the case if optically effective elements which illuminate the same partial area in the base area were combined into groups at predetermined locations on the optical disk.

Because each basic element has an equal number of lenses and prisms, there is the advantage that, on the one hand, uniform and strong illumination of the base area is achieved and, on the other hand, there are sufficient prisms to illuminate large partial areas of the base area with higher light intensity.

The fact that all lenses and prisms have the same square or rectangular base area results in the advantages of a simple and inexpensive feasibility of the construction of the optical disk and a simple and inexpensive manufacture of the tools for producing the optical disk.

These advantages mentioned are achieved in particular if in every row of each basic element every second optically active element is a lens and the lenses and the prisms form a checkerboard pattern, because it is thus achieved that only a small number of prisms or no prisms with their side faces adjoin each other directly, thereby avoiding that due to the different angles that the prisms have, many steep interfaces are created, which would lead to the tools for the manufacture of the optical disk being complex in construction and manufacture and cost-intensive and causing high tool wear would, since the interfaces between the prisms must be very clean, so as not to limit the optical effectiveness of the prisms.

Because some of the predetermined partial areas overlap partially or completely, there is the advantage that, on the one hand, the uniformity of the illumination of the partial areas is increased and, on the other hand, some of the partial areas have an increased light intensity compared to other partial areas, as a result of which predetermined areas of the base area can be particularly emphasized in the light distribution.

It is advantageous that the color of the lens is gray or the vehicle color is adapted or the color of the neighboring lights corresponds, because thus z. B. can be achieved that a rear lamp of a motor vehicle, which consists of several individual lights, provides a uniform appearance, or that the appearance of the vehicle lamp is adapted to the appearance in the color of the vehicle, with the overall result that the formation of Phantom light is suppressed.

The fact that the optical disk is made of plastic gives the advantage of simple and inexpensive manufacture of the motor vehicle lamp.

An embodiment of the invention is shown in the drawings and is described in more detail below with reference to the drawings.

• Figur 1 eine schematische Darstellung einer erfindungsgemäßen Kraftfahrzeugleuchte,
• Figur 2 ein Grundelement einer erfindungsgemäßen Optikscheibe,
• Figur 3 die Einzelheit X entsprechend Figur 2,
• Figur 4a bis 4d Schnitte entsprechend Figur 3,
• Figur 5 die Einzelheit X entsprechend Figur 2 in perspektivischer Darstellung,
• Figur 6 den Strahlengang durch einen Schnitt eines Grundelements,
• Figur 7 ein Lichtverteilungsbeispiel,
• Figur 8a und Figur 8b je einen Schnitt durch eine Linse mit dem entsprechenden Strahlengang,
• Figur 9 ein Ausführungsbeispiel eines Grundelements einer Optikscheibe mit Bezug auf Figur 7.

Show it

• FIG. 1 shows a schematic illustration of a motor vehicle lamp according to the invention,
• FIG. 2 shows a basic element of an optical disk according to the invention,
• FIG. 3 shows the detail X corresponding to FIG. 2,
• 4a to 4d sections corresponding to FIG. 3,
• FIG. 5 shows the detail X corresponding to FIG. 2 in a perspective view,
• FIG. 6 the beam path through a section of a basic element,
• FIG. 7 shows an example of light distribution,
• 8a and 8b each show a section through a lens with the corresponding beam path,
• FIG. 9 shows an exemplary embodiment of a basic element of an optical disk with reference to FIG. 7.

The same or equivalent components and features in the figures are provided with the same reference numerals in all figures.

Figure 1 shows schematically the representation of a motor vehicle lamp according to the invention. In this exemplary embodiment, the motor vehicle lamp has a reflector (R) which is used to concentrate the light (S) emerging from a light source (LI). In order to achieve a predetermined light distribution, the motor vehicle lamp has an optical disc (O), which here also serves as a cover disc in a cost-saving design. So that the light emitted by the motor vehicle light appears in a different color than the color of the optical disc (O), the optical disc (O) is a color filter (F) upstream in the beam path, which can be arranged in any way, since the optical disc alone Light distribution determined so that he z. B. is arranged between the reflector (R) and optical disc (O) or can also be designed as a dome, so that the color filter (F) is arranged in the beam path between the light source (LI) and the reflector (R). The color of the color filter (F) can, for. B. be red. However, any other color that can be used for motor vehicle lights is also conceivable. The optical disc (O) can be colored gray here, for example, so that the emitted light z. B. appears red while the light source (LI) is switched off the motor vehicle lamp appears gray. In another embodiment, a lens can be used to concentrate the light (S), which can replace the reflector (R) or supplement its effect.

The optical disk (O) here consists of a predetermined number of basic elements (GE), one of which is shown in FIG. 2. Each of the basic elements (GE) of the optical disk (O) has a predetermined number of optically active elements, which are designed here as lenses (L) and prisms (P), the lenses (L) being shown hatched. The optically active elements are arranged adjacent to one another in rows, the base area of the optically active elements being chosen to be square here. To ensure easy manufacture and optimal light distribution, the lenses (L) and prisms (P) are arranged in a checkerboard pattern. A basic element (GE) consists here, for example, of eight rows A ... H and seven columns 1 ... 7. The basic element (GE) of the optical disc (O) is shown enlarged here.

In Figure 2, the detail X is also identified, which is shown in more detail in Figure 3. The detail X shows the lenses (L) with the designation (A1, A3, B2, C1 and C3), which are shown hatched here and the prisms (P) with the designation (A2, B1, B3 and C2). It can be seen that the lenses (L) and prisms (P) are laid out in a checkerboard pattern, as a result of which the edges of the prisms do not directly adjoin one another and thus there are no transitions between the prisms that are difficult to manufacture.

In Figure 3, four sections A-A, B-B, C-C, D-D are also identified, which are shown in Figures 4a to 4d.

FIG. 4a shows the section CC according to FIG. 3 through the optical disk (O). The cross section of the can be seen here Prisms (P) with the designation (B1) and (B3) and the lens (L) with the designation (B2). The lens (L) is designed here as a concave scattering lens (L) which has two different scattering radii, which cannot be seen from this illustration. All lenses (L) present in the optical disk have the same configuration with the same scattering behavior. It can also be seen from FIG. 4a that the prisms (P) with the designations (B1) and (B3) deflect the incident light strongly horizontally, namely in opposite directions, because of their angles.

Figure 4b shows the section A-A according to Figure 3. In this figure, the lenses (L) with the designations (A1) and (A3) and the prism (P) with the designation (A2) can be seen. Furthermore, it can be seen that the prism (P) with the designation (A2) does not cause a horizontal deflection of the incoming light.

FIG. 4c shows the section D-D according to FIG. 3. A partial cross section of the optical disc (O) can also be seen in this illustration, which shows the lenses (L) with the designations (C1) and (C3) and the prism (P) with the designation (C2). From this illustration it can also be seen that the prism (P) with the designation (P2) does not cause a horizontal deflection of the incident light. The lenses (L) are identical to the lenses (L) shown above.

The section BB according to FIG. 3 is shown in FIG. 4d. The prisms (P) of the optical disk (O) with the designations (A2) and (C2) and the lens (L) with the designation (B2) can be seen here. In comparison with FIG. 4a, it can be seen that the scattering radius (R2) of the lens (L) with the designation (B2) in the horizontal direction is smaller than the scattering radius (R1) in the vertical direction, as a result of which the scattering in the horizontal direction is greater than the scatter in the vertical direction. These are lenses (L) designed in such a way that the two scattering radii (R1, R2) differ most strongly in perpendicular sections and merge seamlessly into one another. It can also be seen from FIG. 4d that the prism (P) with the designation (A2), which, as already mentioned under FIG. 4b, does not cause a horizontal deflection of the light, causes a vertical deflection of the light due to its angle. The prism (P) with the designation (C2) also deflects the light only in the vertical direction, the two prisms deflecting the light in opposite directions.

FIG. 5 shows a perspective illustration of the detail X according to FIG. 2. In this partial view of the base element (GE) of the optical disk (O) it can be seen that the lenses (L) are all of the same design and the incident light is in each case on the same base area (GF ) to steer. The checkerboard pattern of the lenses (L) and the prisms (P) can also be seen. It can also be seen that the prisms (P) have different vertically and / or horizontally acting deflection angles.

FIG. 6 shows a section through a basic element (GE) of the optical disk (O) with the optically active elements (A1 to A7) of the exemplary embodiment according to the invention. The beam path through these optical elements (A1 to A7) is also shown here. The light (S) impinging on the optical disk (O) from the reflector (R) is directed in parallel. All lenses (L) with the designation (A1, A3, A5 and A7) have the same scattering properties for the light (S). In addition, it can be seen that the prisms (P) with the designation (A2, A4 and A6) do not deflect the incident light (S) horizontally. The vertical deflection properties of the prisms (P) cannot be seen from this illustration.

Figure 8b shows a section as the same section Figure 6 of the lens (L) with the designation (A1) in the horizontal direction.

Figure 8a shows a section through the lens (L) with the designation (A1) in the vertical direction. It can be seen from the two representations that the scattering radius (R1) in FIG. 8a is larger than the scattering radius (R2) in FIG. 8b. This ensures that the incident light (S) is scattered more horizontally than in the vertical direction for all lenses (L). Since the two scattering radii (R1, R2) continuously merge into one another, a scattering lens (L) is obtained which illuminates a rectangular base area (GF) as evenly as possible.

FIG. 7 shows an example of a light distribution to be achieved for a rear fog lamp. Shown is the base area (GF), which is designed here as a rectangular area that extends from the 0 ^° axis in each case by 12.5 ^° in the horizontal direction and in each case by 7.5 ^° in the vertical direction. In this base area (GF), partial areas (TF) are placed, which have the designations 0 to 6, as examples for a rear fog lamp. These partial areas (TF) form an example of a cross through the center of the base area (GF).

The lenses (L) of the exemplary embodiment described here illuminate the base area (GF) uniformly, while the prisms direct the incident light (S) onto the partial areas (TF) and thus increase the light intensity in the area of the partial areas (TF).

A basic element (GE) is shown in FIG. 9, the lenses (L) being identified as hatched areas. The prisms (P) are shown as free areas, a number being indicated in the center of the area, which designates the partial area (TF) which is illuminated by the prism (P), the designation of the partial areas (TF) with the designation in Figure 7 matches. Also points each prism surface has at least one additional number with an associated arrow, the arrows indicating whether the prism is vertically and / or horizontally deflecting and also the number indicating the angle at which the deflection takes place, these degrees being given with the angle information in the figure 7 match.

Each partial area (TF) is exemplarily illuminated by four prisms (P) of each basic element (GE). The partial area (TF) with the designation (O) is z. B. illuminated by the prisms (P) with the designations (A4, C4, E4 and G4). These prisms (P) have, for example, only a vertical deflection of the light (S).

The partial area (TF) with the designation (4) is illuminated by the prisms (P) with the designation (B3, F3, D4, H4). These prisms (P) have a horizontal and a vertical deflection. The partial areas (TF) with the designations 0, 5 and 6) are illuminated by prisms (P), which each cause only a vertical deflection. The partial areas illuminated by the prisms (P) are not congruent, but are selected such that the partial areas (TF) overlap with the adjacent partial areas (TF), as a result of which uniform illumination is achieved beyond the edges of the partial areas identified in FIG. 7 is achieved so that on the one hand it is achieved that a required minimum light intensity is achieved in the motor vehicle lamp according to the invention, and on the other hand it is achieved that a maximum permitted light intensity is not exceeded in the area of the partial surfaces (TF). From this representation in FIG. 9 in connection with the representation in FIG. 7, it can also be seen that each basic element (GE) generates the desired light distribution for itself. The interaction of all basic elements (GE) of the optical disk (O) ensures that the specified light intensity is maintained in the specified areas and also differences in light intensity that are caused by the location of the optical disk and the light incident there. be balanced. This enables the optical disc (O) to be kept as small as possible and a light source, such as. B. a light bulb can be used, which has a usual nominal power, although the motor vehicle lamp has a color filter (F), which reduces the light intensity by about half.

The optical disc (O) can be made of plastic in order to keep the manufacturing costs low. The optical disc (O) can also be made of glass.

Claims (9)

1. Motor vehicle light with 1) a reflector (R) and / or a lens for focusing the 2) a light source (LI) emerging light (S), with 3) an optical disc (O), which is connected downstream in the beam path, the
3.1) has optically effective elements that
3.1.1) are arranged adjacent to one another in rows, wherein
3.1.2) a predetermined number of elements is designed as lenses (L) and
3.1.2.1) each lens (L) is designed as a concave or convex scattering lens (L) with two scattering radii, which scatters the incident light (S) onto a base area (GF) arranged at a predetermined distance from the motor vehicle lamp, whereby
3.1.2.2) the vertical scattering radius (R1) is greater than the horizontal scattering radius (R2) of the scattering lenses (L) and
3.1.2) the remaining number of elements is designed as prisms (P), wherein
3.1.3.1) each prism (P) is designed as a horizontally and / or vertically acting prism (P) which directs the incident light (S) onto a given partial area (TF) of the base area (GF) and the
3.2) is colored in a color that differs from the color of the emitted light and with 4) a color filter (F) in the beam path between the reflector (R) and / or the lens for focusing the light and the optical disc (O) and / or in the beam path between the light source (I) and the reflector (R) or the lens for focusing the light. 2. Motor vehicle lamp according to claim 1, characterized in that the optical disc (O) is divided into a predetermined number of basic elements (GE), that each basic element (GE) has the same predetermined sequence and number of prisms (P) and lenses (L) and that each basic element (GE) generates the same predetermined light distribution. 3. Motor vehicle lamp according to claim 2, characterized in that each basic element (GE) has an equal number of lenses (L) and prisms (P). 4. Motor vehicle lamp according to claim 3, characterized in that all lenses (L) and prisms (P) have the same square or rectangular base. 5. Motor vehicle lamp according to claim 4, characterized in that in each row (A, B, ...) of each basic element (GE) every second optically active element is a lens (L). 6. Motor vehicle lamp according to claim 5, characterized in that the lenses (L) and the prisms (P) form a checkerboard pattern. 7. Motor vehicle lamp according to one of the preceding claims, characterized in that some of the predetermined partial areas (TF) overlap partially or completely. 8. Motor vehicle light according to one of the preceding claims, characterized in that the color of the optical disc (O) is gray or the vehicle color is adapted or corresponds to the color of the adjacent lights. 9. Motor vehicle lamp according to one of the preceding Claims, characterized in that the optical disc (O) consists of plastic.

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