FR2635166A1 - AUTOMOTIVE HEADLIGHT COMPRISING AN INTERMEDIATE DEFLECTION GLASS - Google Patents

Abstract

The present invention relates to an automobile headlight. This automobile headlight has a bulb, a reflector, a glass constituting a filter as well as another glass 4, arranged between the bulb and the first glass and provided on its outer face with a screen having passages for the light. the optically active surfaces of which form an angle which is in turn positive and negative less than 90degre (s) with respect to the planes parallel to the optical axis 10, and on its internal face of convex optical means 5 facing the passages for the light and grooves 6 of triangular section facing the opaque areas of the screen. The headlight according to the invention can be used in particular as a reversing light.

Description

The present invention relates to a car headlight, in particular a

  reversing light, having optical means for making the light parallel, an ampoule, a glass constituting a filter and another glass, arranged between the bulb and the first glass, provided with other optical means and provided on its outer face of a screen having passages for the light and on its inner face convex optical means facing the

passages for the light.

  With regard to traffic lights, it has become customary to dispose of baffle lenses or intermediate lenses at an appropriate position between the glass and the bulb. Such an intermediate glass consists of a number of transparent parts which are each arranged in the optical axis of convergent optical elements. A screen grid which is located between the light source and the glass is intended to limit the attenuation of light to the extent necessary to let all rays gathered in beams through the converging lenses and also, when the lighthouse is not lit, to produce a

  colorful reflection responsible for the desired colorful look of the lighthouse.

  GM 8533666 discloses a lighthouse in which the area fraction occupied by the opaque areas has been enlarged relative to that occupied by the transparent areas primarily in order to obtain an improvement in the appearance of the headlight when no is not lit. The lower refraction of the light rays that then occur due to the concave refraction domains located on the outer face of the dispersing element in the transparent range may seem sufficient, it is true, in the case of traffic lights, but not in the case of recoil lights. For the latter there is, with regard to the directivity of their light beams, substantially different requirements as regards the distribution of light and the luminous intensity. Thus, the object of the invention is to propose a car headlight whose optically active elements guarantee the distribution of light required by the regulation of

  the EEC and paragraph 52 of the Regulations concerning the

  StVZO vehicles and the necessary light intensities, despite the use of a screen

glass constituting a filter.

  According to the invention this object is achieved in that the optically active surfaces of the light passages form a positive and negative angle, less than 90, with respect to the planes parallel to the optical axis and that the areas of the glass made opaque by the screen are located in front of grooves of triangular section being centered thereon. Positive and negative angles can then take a value of about 80. Such a headlight is particularly suitable as a reversing headlight, the external covering glass constitutes a filter and absorbs as a rule a large part of the light. It is therefore advantageous for the light to be radiated by being directed into specific angular domains which at the same time represent the points of

  measure for the necessary values of luminous intensity.

  Other advantageous features of the invention are constituted by the fact that the light beam reaching the middle of the side of a triangular groove is deflected on the center of the passages for the flat surface light and that the triangular grooves are of such depth that the light arriving on one side of the grooves completely spring through the passages for the light. The surface of the passages for the light is such that all the light that reaches one side of the grooves passes through the passages for the light. The light thus concentrated, transmitted and directed by the entire basic light beam constituting the light radiated corresponds exactly to the prescriptions of the standards concerning the reversing headlights. The triangular, prism-shaped grooves then allow the light directed into the

  passage for light is still guided and concentrated without

  sensitive persion. According to another suitable feature of the invention, which contributes substantially to this, the means

  Convex optics form an obtuse angle on the frontal surface.

  Thus, four flat surfaces on the front face, which represent

  Together, convergent optical means fulfill all the conditions for concentrated guidance of light through passage openings in the screen grid. A particular advantage concerning the manufacture of glass provided with the optical means which have just been described is constituted by the fact

  that it suffices to form flat surfaces devoid of counter

  stripping which allows a simple and inexpensive manufacture.

  But other features and benefits of

  the invention will become more apparent in the detailed description which

  follows and refers to the accompanying drawings, given solely by way of example, showing a headlight in the form of a reversing headlight, and in which: - Figure 1 is a sectional view of a reversing headlight, - Figure 2 is a cut of an intermediate glass provided

optical means.

  In the example shown in FIGS. 1 and 2, an intermediate glass 4 is placed between a glass 1 constituting a filter and a reflector 3 placed behind a light source 2. The light made parallel by the reflector 3 or by a prismatic glass (not shown ) reaches, as shown in Figure 2, convex optical means 5 forming an obtuse angle on the input face of the intermediate glass 4 and the triangular grooves 6 laterally limiting the previous. The triangular grooves 6 are associated on the output face, opaque areas 7 of the intermediate glass 4 which are located opposite the grooves being centered thereon. Opposite the optical means 5 and on the exit face are passages for the Light 8 whose planar exit surfaces 9 make an angle (a) in turn positive and negative with respect to the vertical planes parallel to the optical axis 10. This ensures that all parallel light rays reaching the intermediate glass 4 are optimally deflected onto the exit surfaces 9 of the light passages 8 by the convex optical means 5 and the sides of the triangular grooves 6 which limit them. Laterally, so that the minimum light intensities required for a reversing light are obtained without problem at their measurement points. This is also achieved insofar as it is a gray reversing beacon in which the glass 1 is gray, the intermediate glass 4 is colorless and the opaque areas 7 are black or silver bands. In the case of a colored, for example red, lighthouse, the glass 1 would be pink, the intermediate glass 4 would be blue and the opaque areas 7 would represent red stripes. According to needs he is

  possible to provide the glass 1 with dispersing means.

Claims (6)

  1. An automobile headlight, in particular a reversing headlamp, having optical means for making the light parallel, an ampoule, a glass constituting a filter and another glass, arranged between the bulb and the first glass, provided with other optical means and provided on its outer face with a screen having passages for the light and on its inner face convex optical means facing the passages for the light, characterized in that the optically active surfaces 9 passages for the light 8, form an angle (a) in turn positive and negative less than 90 relative to the planes parallel to the optical axis 10 and in that the areas 7 of the glass 4 made opaque by the screen are located in front of grooves 6 of triangular section being centered on them.   2. An automobile headlight according to claim 1, characterized   in that the positive and negative angles are about 0. 3. Headlight according to claim 1, characterized in that the light beam reaching the middle of the side of a triangular groove 6, is deflected on the center of   passages for the flat surface light 8.   4. Automobile headlight according to claim 1, characterized in that the triangular grooves 6 are of such depth that the light arriving on the side of the grooves   fully integral with the passageways for the light 8.   5. An automobile headlight according to claim 1, characterized in that the surface 9 of the passages for the light 8 is such that any light which reaches one side of the grooves 6   crosses the passages for the light 8.   6. Automobile headlight according to claim 1, characterized in that the convex optical means 5 form on the frontal side an obtuse angle.