Patent Abstract:
The invention relates to a motor vehicle headlight having at least one first light source and a headlight lens which comprising, for example, a blank-molded integrally formed body which is made from a transparent material, and which comprises at least one light tunnel and a light-conducting part having at least one optically effective light exit surface, wherein the light tunnel comprises, an optically effective, light entry surface and merges, while forming a kink, into the light-conducting part for imaging the kink as a light-dark boundary by means of light coupled in or radiated into the light entry surface from the first light source, wherein the light tunnel has a transition region in which the surface delimiting the light tunnel at the top rises in the direction of the light-conducting part.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. nationalization under 35 U.S.C. §371 of International Application No. PCT/EP2013/001185, filed Apr. 22, 2013, which claims priority to German Application No. 102012010357.3, filed May 26, 2012, and German Application No. 102013001071.3, filed Jan. 23, 2013. 
     FIELD OF THE INVENTION 
     The invention relates to a vehicle headlight including a headlight lens, which has a body from transparent material including at least one light entry face and at least one optically operative (or effective) light exit face. The invention also relates to a headlight lens, which has a body from transparent material including at least one light entry face and at least one optically operative (or effective) light exit face. 
     BACKGROUND INFORMATION 
     DE 203 20 546 U1 discloses a lens blank-molded on both sides and having a curved surface, a planar surface and a retention edge molded onto the lens edge, wherein a supporting edge of a thickness of at least 0.2 mm and projecting with respect to the planar surface is molded onto the retention edge. Herein, the supporting edge is molded onto the outer circumference of the headlight lens. A further headlight lens having a supporting edge is disclosed e.g. by DE 10 2004 048 500 A1. 
     DE 20 2004 005 936 U1 discloses a lens for illuminating purposes, in particular a lens for a headlight for imaging light emitted from a light source and reflected by a reflector for generating a predetermined illumination pattern, said lens having two opposing surfaces, wherein areas of different optical dispersion effects are provided on at least one first surface. 
     DE 103 15 131 A1 discloses a headlight for vehicles having at least one two-dimensional luminous field including a plurality of illuminating element (diode) chips and an optical element disposed in the light path of the light beam emitted by the luminous field, wherein the illuminating element chips of the luminous field are disposed in a common recess, and that the recess, on a side facing the direction of light emission, has an outer edge which, in relation to the illuminating element chips, is spatially arranged such that a predetermined gradient of light density is formed in a light dispersion of the headlight in the area of the outer edges. 
     DE 10 2004 043 706 A1 discloses an optical system for a motor vehicle headlight (headlamp) for dispersing a beam of light rays from an illuminant, with an optical primary element being provided, which has an optical face including a break or discontinuity extending along a line, wherein the optical face is formed smooth at least on one side adjacent the discontinuity so that the beam of light rays is separated into two partial beams of light rays. Herein, it is provided for that at least one of the partial beams of light rays has a sharp edge of limitation. Moreover, the optical system comprises an optical secondary element for imaging the sharp edge of limitation (restriction) on to a predetermined light-dark-boundary. 
     DE 195 26 512 B4 discloses an illumination device for vehicles, in which light exiting from an optical cable is emitted in a forward direction through a lens body, wherein the illumination device comprises a light conductor of light-transmissive material, which conductor is disposed between a light exit end of the optical cable and a light entry end of the lens body, wherein the light conductor has a light entry face which is configured such that it completely covers the exit light end of the optical cable. The lens body comprises a light entry end which is manufactured separately of the light conductor which is configured such that it contacts the light exit face of the light conductor and covers the light exit face of the light conductor sufficiently and emits a light flux from the light exit face in a forward direction as a light flux having a desired light distribution which is based on a configuration of its light exit face. Herein, the light exit face of the light conductor comprises a central part, which extends through a focal point of the lens body and is configured perpendicularly with respect to an optical axis of the lens body. 
     DE 102 52 228 A1 discloses a headlight including at least one light source as well as at least one a light termination body associated with the light source and having a light entry face for making light emitted from the light source enter, and a light exit face as well as at least one lens which cooperates with the light exit face and is arranged in the light emitting direction following the light termination body and images the light made to exit from the light termination body, wherein the light termination body has a cross section corresponding to the light distribution to be achieved, wherein the cross section of the light termination body increases from the light entry face in the direction of the light exit face. 
     Further illumination means in context with vehicles are disclosed by DE 42 09 957 A1, DE 41 21 673 A1, EP 1 357 333 A2, DE 43 20 554 A1, DE 195 26 512 A1, DE 10 2009 008 631 A1, U.S. Pat. No. 5,257,168 and U.S. Pat. No. 5,697,690. 
     It is, in particular, an object of the invention to suggest an improved headlight lens for a vehicle headlight, for example for a motor vehicle headlight. It is a further object of the invention to reduce the costs for manufacturing vehicle headlights. It is a further object of the invention to reduce the costs for manufacturing motor vehicles. It is a still further object of the invention to suggest a vehicle having particularly compact low-beam headlights. 
     SUMMARY 
     The aforementioned object is achieved by a headlight lens for a vehicle headlight, for example for a motor vehicle headlight, wherein the headlight lens comprises a for example blank-molded, for example monolithic, body of transparent material, wherein the body comprises at least one light tunnel and at least one light passage section including at least one optically operative light exit face, wherein the light tunnel comprises at least one for example optically operative light entry face and, via a bend, forms transition into the light passage section for imaging the bend as a bright-dark-boundary by means of light made to enter or irradiated, respectively, into the light entry face, and wherein the light exit face comprises at least two, for example at least three segments (which are separated from each other for example by means of an indentation or of a bend or of a point of discontinuity). 
     A segment is, for example, an area or zone according to a (mathematical or geometrical, respectively) function, which differs from the (mathematical or geometrical, respectively) function of a neighbouring segment. A segment is, for example, an optically operative area or zone according to a (mathematical or geometrical, respectively) function, which differs from the (mathematical or geometrical, respectively) function of a neighbouring segment. 
     A segment of the light exit face is, for example, an optically operative area or zone according to a (mathematical or geometrical, respectively) function, which differs from the (mathematical or geometrical, respectively) function of a neighbouring segment of the light exit face. 
     An optically operative (or effective) light entry (sur-)face and/or an optically operative light exit (sur-)face, respectively, is an optically operative surface of the, e.g. monolithic, body. An optically operative (sur-)face is, in particular, a surface of the transparent body, at which surface, when using the headlight lens according to its purpose, light will be refracted. An optically operative surface is, in particular, a surface at which, when using the headlight lens according to its purpose, the direction of light which passes through this surface will be changed. 
     Transparent material is in particular glass. Transparent material is for example inorganic glass. Transparent material is for example silicate glass. Transparent material is for example glass as described in PCT/EP2008/010136. Glass for example comprises
         0.2 to 2% by weight Al 2 O 3 ,   0.1 to 1% by weight Li 2 O,   0.3, in particular 0.4 to 1.5% by weight Sb 2 O 3 ,   60 to 75% by weight SiO 2 ,   3 to 12% by weight Na 2 O,   3 to 12% by weight K 2 O, and   3 to 12% by weight CaO.       

     Herein, the term blank-molding is, in particular, to be understood in a manner that an optically operative surface is to be (injection) molded under pressure such that any subsequent finishing or post-treatment of the contour of this optically operative face may be dispensed with or does not apply or will not have to be provided for, respectively. Consequently, it is particularly provided for that, after blank-molding, the blank-molded surface is not ground, (i.e. it will not [have to] be treated by grinding). 
     A light tunnel is, in particular, characterized in that essentially total reflection takes place by/at its lateral (for example top, bottom, right and/or left) surfaces, so that light entering the light entry face is conducted through the tunnel as a light guide (conductor). A light tunnel is in particular a light guide or light conductor. In particular, it is provided for that total reflection occurs at the longitudinal surfaces of the light tunnel. In particular, it is provided for that the longitudinal surfaces of the light tunnel are intended for total reflection. In particular, it is provided for that total reflection is achieved on the surfaces of the light tunnel essentially oriented in the direction of the optical axis of the light tunnel. In particular, it is provided for that the surfaces of the light tunnel essentially oriented in the direction of the optical axis of the light tunnel are destined for total reflection. A light tunnel e.g. tapers in the direction of its light entry face. A light tunnel e.g. tapers in the direction of its light entry face by at least 3°. A light tunnel tapers e.g. in the direction of its light entry face by at least 3° with respect to its optical axis. A light tunnel tapers e.g. at least partially in the direction towards its light entry face. A light tunnel favourably tapers at least partially in the direction of its light entry face by at least 3°. A light tunnel tapers e.g. at least partially in the direction of its light entry face by at least 3° with respect to its optical axis. 
     A bend is, in particular, a curved transition. A bend is, for example, a curved transition having a radius of curvature of no less than 50 nm. For example, it is provided for that the surface of the headlight lens has no break or discontinuity in the bend, but rather a curve or curvature. For example, it is provided for that the surface of the headlight lens in the bend has a curvature, for example, with a radius of curvature of the curve in the bend of no less than 50 nm. In an embodiment the radius of curvature is no larger than 5 mm (for example for implementing fog light). In an expedient embodiment the radius of curvature is no more than 0.25 mm (e.g. for implementing dipped-beam headlight), for example, no more than 0.15 mm, e.g. no more than 0.1 mm. In a further embodiment, the radius of curvature of the curve in the bend is at least 0.05 mm. For example, it is provided for that the surface of the headlight lens is blank-molded in the region of the bend. 
     According to an embodiment the light tunnel has a transitional area in which the surface (of the light tunnel) restricting the light tunnel in an upward direction rises in the direction towards the light passage section, and/or wherein the surface (of the light tunnel) restricting the light tunnel in an upward direction (for example, when regarded or seen in or with respect to the longitudinal direction, respectively, and/or when regarded or seen in or with respect to the orientation/direction of the optical axis of the light tunnel and/or of the optical axis of the light passage section and/or the optical axis of the light exit face, respectively) has an inflection point, and/or wherein the surface (of the light tunnel) restricting the light tunnel in an upward direction includes (for example, when regarded or seen in or with respect to the longitudinal direction, respectively, and/or when regarded or seen in or with respect to the orientation/direction of the optical axis of the light tunnel and/or of the optical axis of the light passage section and/or the optical axis of the light exit face, respectively) a concavely curved area, e.g. having a radius of curvature of at least 10 mm, e.g. having a radius of curvature of at least 20 mm. In a further embodiment, the surface (of the light tunnel) restricting the light tunnel in a downward direction extends (in particular essentially) horizontally in the transitional area. In a further embodiment, the surface (of the light tunnel) restricting the light tunnel in a downward direction extends (in particular essentially) in parallel to the optical axis of the headlight lens in the transitional area. In a further embodiment, the transitional area is provided for/configured in that half of the light tunnel, which is facing the light passage section. In a further embodiment, the transitional area is provided for/configured only in that half of the light tunnel, which is facing the light passage section. In a further embodiment, the surface (of the light tunnel) restricting the light tunnel upwardly includes a/the point of inflection in the transitional area. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in the upward direction forms transition into the light passage section with a continuous first derivative. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in the upward direction forms a continuous transition into the surface (of the light passage section) limiting the light passage section upwardly. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in the upward direction forms transition into the surface (of the light passage section) limiting the light passage section in an upward direction, with a continuous first derivative. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in the upward direction includes a concavely curved area in the area of transition. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in the upward direction includes a concavely curved area in the area of transition having a radius of curvature of at least 20 mm. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in an upward direction extends continuously. In a further embodiment, the surface (of the light tunnel) limiting the light tunnel in an upward direction extends with a continuous first derivative. In a further embodiment, the light passage section tapers (in a portion facing the light tunnel) in the direction of the light tunnel. 
     In a further embodiment, the light exit face comprises at least three segments, which, in particular, are separated from one another by means of an indentation/notch or by a bend. 
     In a further embodiment, the (first) light source and the (first) light entry face are configured and disposed with respect to each other such that light from the (first) light source enters the (first) light entry face with a light flux density of at least 75 lm/mm 2    
     In a further embodiment, the light tunnel is disposed between the bend and the light entry face. In a further embodiment, the light passage section is arranged between the bend and the light entry face. For example, it is provided for that light entering the transparent body through the light entry face and entering the passage section in the region of the bend from the light tunnel will exit from the light exit face at an angle of between −20° and 20° with respect to the optical axis. For example, it is provided for that light entering the transparent body through the light entry face will exit from the light exit face at an angle of between −20° and 20° relative φ the optical axis. For example, it is provided for that light entering the transparent body through the light entry face and, from the light tunnel, entering the passage section in the area of the bend, will exit from the light exit face essentially in parallel relative to the optical axis. For example, it is provided for that light entering the transparent body through the light entry face, will exit from the light exit face essentially in parallel relative to the optical axis. 
     In a further embodiment, the bend comprises an opening angle of at least 90°. In a further embodiment, the bend includes an opening angle of no more than 150°, preferably an opening angle of no more than 120°. In a further favourable embodiment, the bend is disposed on a surface of the light passage section, which surface is facing the light entry (sur-)face. 
     In a further embodiment, the orthogonal of the light entry face is inclined with respect to the optical axis of the light passage section. In a further embodiment, the light entry face is inclined with respect to the optical axis of the light passage section by an angle of between 5° and 70°, for example by an angle of between 20° and 50°. 
     In a further embodiment, the light tunnel comprises a region on its surface, which region essentially corresponds to a part of the surface of an ellipsoid. In a further embodiment, the light tunnel comprises a region on its surface, which region corresponds essentially to at least 15% of the surface of an ellipsoid. 
     In a yet further embodiment, the light tunnel comprises a region on its surface, for which region the following applies: 
     
       
         
           
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                 75 
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                 a 
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             in which
           z is a coordinate in the direction (of the optical axis) of the light tunnel;   x is a coordinate orthogonal to the direction of the optical axis of the light tunnel;   y is a coordinate orthogonal to the direction of the optical axis of the light tunnel;   a is a number having a value greater than 0;   b is a number having a value greater than 0; and   c is a number having a value greater than 0.   
         
           
         
       
    
     In a further embodiment a surface of the light passage section facing the light tunnel is curved at least in the region of the bend towards the transition into the light tunnel, the curvature being, for example, convex. In a further embodiment, the bend is curved in its longitudinal extension. In a further embodiment, the bend is curved, in its longitudinal extension, the bend having a radius of curvature of between 5 mm and 100 mm. In a still further embodiment, the bend is curved, in its longitudinal extension, corresponding to a Petzval curve (also termed Petzval [sur]face). 
     In a further embodiment, the bend comprises, in its longitudinal extension, a curvature having a radius of curvature in the orientation of the optical axis of the light tunnel and/or of the light passage section. In a yet further preferred embodiment of the invention, the radius of curvature is orientated opposite to the light exit face. 
     In a further embodiment, the bend is curved in a first direction and in a second direction. In a further embodiment, the first direction is orthogonal to the second direction. In a still further embodiment, the bend is curved with a first radius of curvature in a first direction and with a second radius of curvature in a second direction, wherein the second radius of curvature is positioned orthogonal to the first radius of curvature. 
     In a further embodiment, a portion of the surface of the passage section facing the light tunnel has a configuration of a Petzval face. In a yet further embodiment, the surface of the light passage section facing the light tunnel is, in a region in which it forms a transition into the light tunnel, configured as a Petzval face. 
     In a further embodiment, the length of the headlight lens, when looked at in the orientation of the optical axis of the light tunnel and/or the light passage section, amounts to no more than 7 cm. 
     In a further embodiment, the headlight lens or the transparent body, respectively, includes a further light exit face as well as a further light entry face. In a further embodiment, at least 20% of the light entering the light entry face and exiting through the light exit face will exit through the light exit face, after having exited from the transparent body through the further light exit face, and after having entered the transparent body through the further light entry face. In a further embodiment, at least 10%, for example at least 20% of the light entering the light entry face and exiting through the light exit face will exit through the light exit face without having exited from the transparent body through the further light exit face and without having entered the transparent body through the further light entry face. In a further embodiment, at least 75% of the light entering the light entry face and exiting through the light exit face will exit through the light exit face after having exited from the transparent body through the further light exit face and after having entered the transparent body through the further light entry face. In a further embodiment, it is provided for that light which enters the transparent body through the light entry face and enters the light passage section from the light tunnel in the region of the bend will either exit from the transparent body from the further light exit face and enter the further light entry face of the transparent body as well as it will exit from the transparent body from the light exit face, or it will exit directly from the light exit face (without exiting from the transparent body from the further light exit face and without entering the further light entry face of the transparent body). 
     In a further embodiment, the vehicle headlight has no secondary optic associated with the headlight lens. A secondary optic is, in particular, an optic means for aligning light which exits from the light exit face or from the last light exit face of the headlight lens, respectively. A secondary optic is in particular an optical element for aligning light, which element is separated from and/or subordinated with regard to the headlight lens. A secondary optic is in particular no cover nor a protection disc, respectively, but an optical element provided for aligning light. An example of a secondary optic is e.g. a secondary lens as has been disclosed in DE 10 2004 043 706 A1. 
     In particular, it is provided for that the bend, which is imaged as a bright-dark-boundary lies in the lower region of the light tunnel. 
     The aforementioned object is, moreover, achieved by a headlight comprising a aforementioned headlight lens and a (first) light source for irradiating light into the light entry face. 
     In a yet further embodiment, the distance of the light source from the centre of the (first) light exit face, when seen in the orientation of the optical axis of the light tunnel and/or the light passage section amounts to no more than 10 cm. In a further embodiment, the length of the vehicle headlight, when seen in the orientation of the optical axis of the light tunnel and/or the light passage section amounts to no more than 10 cm. 
     In a further embodiment, the vehicle headlight comprises at least one second light source, which is spatially separated from the (first) light source, for making light enter or irradiating light into, respectively the light tunnel and/or directly (i.e. in particular without passing the light tunnel) into the light passage section. It may be provided for that a second light source comprises several partial light sources. In a further embodiment, the vehicle headlight comprises at least one second light source, which is spatially separated from the (first) light source, for making light enter a surface of the light passage section facing the light tunnel. In a further embodiment, light above and/or below the bright-dark-boundary is irradiated by means of the second light source. 
     In a further embodiment, the second light source includes a cornering light source disposed, for example, to the left of the optical axis of the light tunnel and/or above the optical axis of the light tunnel and/or of the light tunnel. In a further embodiment, the corner-light source is disposed between the (first) light entry face and the light passage section. In a further embodiment, the second light source includes a for example further cornering light source arranged, for example, to the right of the optical axis of the light tunnel, and/or above the optical axis of the light tunnel, and/or of the light tunnel. In a further embodiment, the corner-light source is disposed between the (first) light entry face and the light passage section. 
     In a further embodiment, the second light source comprises at least one partial light source disposed above the light tunnel. In a further embodiment, the second light source comprises at least two partial light sources, which are, for example, spatially separated from one another and disposed above the light tunnel. In a further embodiment, the second light source comprises at least one partial light source disposed below the light tunnel. In a further embodiment, the second light source comprises at least two partial light sources, which are, for example, spatially separated from one another and disposed below the light tunnel. In a further embodiment, the or one partial light source or several partial light sources is/are disposed between the (first) light entry face and the light passage section. 
     In an embodiment, a light source, a corner-light source and/or a partial light source comprise at least one LED or an array of LEDs. In an expedient embodiment, the light source comprises at least one OLED or an array of OLEDs. For example, the light source may well be an areal/planar luminous field. The light source may also comprise light element chips as have been disclosed in DE 103 15 131 A1. A light source may be a laser, as well. A suitable laser is disclosed in ISAL 2011 Proceedings, page 271ff. 
     In a further embodiment, the surface restricting the light tunnel for example in the upward direction, includes an indentation or notch extending (essentially) in the longitudinal direction and/or (essentially) in parallel to the optical axis of the light tunnel and/or to the optical axis of the light passage section and/or to the optical axis of the light exit face. In a yet further embodiment, the indentation separates two segments of the light tunnel, which for example emanate from the light entry face. In a further embodiment, a segment or a part of the segments comprises an area on its surface, which area essentially corresponds to a part of the surface of an ellipsoid. This area corresponds for example to the upper surface of a respective segment. In a further embodiment, the segments comprise an area on the surface, which corresponds essentially to a part of the surface of an ellipsoid. This area corresponds, in particular, to the upper surface of a respective segment. 
     It may be provided for that a light entry face and/or a light exit face include/s a light dispersing structure. A light dispersing structure may, for example, be a structure as has been disclosed in DE 10 2005 009 556 A1 and in EP 1 514 148 A1 and EP 1 514 148 B1, respectively. 
     The aforementioned object is, moreover, achieved by a headlight lens for example comprising one or several of the aforementioned features—for a vehicle headlight, for example for a motor vehicle headlight, wherein the headlight lens comprises a for example blank-molded, for example monolithic, body of transparent material, wherein the body comprises at least one light tunnel and at least one light passage section including at least one optically operative light exit face, wherein the light tunnel comprises at least one, for example optically operative, light entry face and, via a bend, forms transition into the light passage section for imaging the bend as a bright-dark-boundary by means of light made to enter or irradiated, respectively, into the light entry face, wherein the surface limiting the light tunnel in particular in the upward direction includes an indentation or at least two indentations (notches) extending at least (essentially) in the longitudinal direction and/or (essentially) in parallel to the optical axis of the light tunnel and/or to the optical axis of the light passage section and/or to the optical axis of the light exit face. 
     In a further embodiment, the indentation separates two segments of the light tunnel for example emanating from the light entry face. In a further embodiment a segment or a part of the segments comprises an area on its surface, which corresponds essentially to a part of the surface of an ellipsoid. This area corresponds, in particular, to the upper surface of a respective segment. In a further embodiment, the segments comprise an area on their surface, which essentially corresponds to a part of the surface of an ellipsoid. This area corresponds, in particular, to the upper surface of the respective segment. 
     In a further embodiment, the at least two indentations separate at least three segments of the light tunnel, said segments, for example, emanating from the light entry face. 
     The aforementioned object is, moreover, achieved by a headlight lens for example comprising one or several of the aforementioned features—for a vehicle headlight, for a motor vehicle headlight, wherein the headlight lens comprises a for example blank-molded, for example monolithic, body of transparent material, wherein the body comprises at least one light tunnel and at least one light passage section including at least one optically operative light exit face, wherein the light tunnel comprises at least one for example optically operative light entry face and, via a bend, forms transition into the light passage section for imaging the bend as a bright-dark-boundary by means of light made to enter or irradiated, respectively, into the light entry face, wherein the light tunnel includes at least two, for example at least three segments emanating from the light entry face. 
     A segment of the light tunnel extends, for example in its longitudinal alignment (essentially) in the longitudinal direction of the headlight lens and/or (essentially) in parallel to the optical axis of the light tunnel and/or to the optical axis of the light passage section and/or to the optical axis of the light exit face. 
     Herein a motor vehicle is, in particular, a land vehicle for individual use in road traffic. Herein, motor vehicles are, in particular, not restricted to land vehicles including a combustion engine. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an example of an embodiment of a motor vehicle; 
         FIG. 2  shows an example of an embodiment of a headlight lens for implementation in the motor vehicle according to  FIG. 1 ; 
         FIG. 3  shows a cut-out representation of a headlight lens of the motor vehicle headlight lens according to  FIG. 2  by way of a perspective view from below; 
         FIG. 4  shows an enlarged representation of a cut-out cross section of a bend for the transition of a light tunnel into a light passage section of a headlight lens according to  FIG. 3 ; 
         FIG. 5  shows a cut-out representation of a headlight lens according to  FIG. 3  by way of a side view; 
         FIG. 6  shows a cut-out representation of a light tunnel of the headlight lens of  FIG. 3  by way of a side view; 
         FIG. 7  shows an example of embodiment of an ellipsoid; 
         FIG. 8  shows the ellipsoid according to  FIG. 7  with a superimposing representation of a portion of the light tunnel represented in  FIG. 6  by way of a cross sectional representation; 
         FIG. 9  shows a side view of an alternative example of embodiment of a motor vehicle headlight (for use in the motor vehicle according to  FIG. 1 ); 
         FIG. 10  shows a side view of a further alternative example of embodiment of a motor vehicle headlight (for use in the motor vehicle according to  FIG. 1 ); 
         FIG. 11  shows an example of embodiment of a headlight lens of the motor vehicle headlight according to  FIG. 10  by way of a top view; 
         FIG. 12  shows the headlight lens according to  FIG. 11  by way of a rear view; 
         FIG. 13  shows a bright-dark-boundary generated by means of the motor vehicle headlight according to  FIG. 10 ; 
         FIG. 14  shows a side view of a further alternative example of embodiment of a motor vehicle headlight (for use in the motor vehicle according to  FIG. 1 ); 
         FIG. 15  shows the motor vehicle headlight according to  FIG. 14  by way of a top view; 
         FIG. 16  shows an example of embodiment of the headlight lens of the motor vehicle headlight according to  FIG. 14  by way of a rear view; 
         FIG. 17  shows a principle representation of an example of embodiment of the superimposition of two ellipsoids; 
         FIG. 18  shows a side view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 19  shows the motor vehicle headlight according to  FIG. 18  by way of a top view; 
         FIG. 20  shows a side view of a further example of an embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 21  shows a cut-out side elevation of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 22  shows a side elevation of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 23  shows a view from the rear of the motor vehicle headlight according to  FIG. 22 ; 
         FIG. 24  shows a top view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 25  shows a bright-dark-boundary generated by means of the motor vehicle headlight according to  FIG. 24 ; 
         FIG. 26  shows a top view of an example of embodiment of a motor vehicle headlight array for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 27  shows a bright-dark-boundary generated by means of the motor vehicle headlight according to  FIG. 24 ; 
         FIG. 28  shows a top view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 29  shows a top view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 30  shows a top view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; 
         FIG. 31  shows the motor vehicle headlight lens according to  FIG. 30  by way of a side view; 
         FIG. 32  shows the headlight lens according to  FIG. 30  by way of a top view; 
         FIG. 33  shows the headlight lens according to  FIG. 30  by way of a perspective representation from the rear; 
         FIG. 34  shows the headlight lens according to  FIG. 30  by way of a further perspective representation from the rear; 
         FIG. 35  shows the headlight lens according to  FIG. 30  by way of a further perspective representation from the rear; 
         FIG. 36  shows a bright-dark-boundary generated by means of the motor vehicle headlight according to  FIG. 30 ; 
         FIG. 37  shows a side view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 ; and 
         FIG. 38  shows a side view of a further example of embodiment of a motor vehicle headlight for use in the motor vehicle according to  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an example of embodiment of a motor vehicle  1  including motor vehicle headlights  10  and motor vehicle headlights/partial headlights  3001 ,  3002 ,  3003 , and  3004 , which are integrated in the body of the motor vehicle  1  within the central third of the front of the motor vehicle  1 . The motor vehicle headlights  10  are, e.g., integrated in the body of the motor vehicle  1  within the marginal area of the front of the motor vehicle  1 . 
       FIG. 2  shows a side view of the motor vehicle headlight  10  including a headlight lens  100 , but without any housing, fittings and energy supply, with the headlight lens  100  being represented in  FIG. 3  in a cut-out manner by way of a perspective bottom view (view from below). The headlight lens  100  comprises a blank-molded monolithic body made from inorganic glass, for example glass which comprises
         0.2 to 2% by weight Al 2 O 3 ,   0.1 to 1% by weight Li 2 O,   0.3, in particular 0.4, to 1.5% by weight Sb 2 O 3 ,   60 to 75% by weight SiO 2 ,   3 to 12% by weight Na 2 O,   3 to 12% by weight K 2 O, and   3 to 12% by weight CaO.       

     The blank-molded monolithic body comprises a light tunnel  108 , which, on its one side, has a light entry face  101  and, on another side, transits into a light passage (conductive) section  109  (of the blank-molded monolithic body) via a bend  107  curved in two spatial directions, which section  109  has a light exit face  102 , a light entry face  103  as well as a further light exit face  104 . The headlight lens  100  is configured such that light entering the headlight lens  100  through the light entry face  101  and, in the region of the bend  107  entering the passage section from the light tunnel  108 , will exit from the light exit face  104  essentially in parallel to the optical axis  120  of the headlight lens  100 . Herein, the light passage section  109  images the bend  107  as a bright-dark-boundary. A portion of the surface of the light passage section  109  facing the light tunnel  108  is configured as a Petzval surface, said surface portion having been designated by reference numeral  110 . 
     The motor vehicle headlight  10  includes a light source  11  configured as an LED, and a light source  12  configured as an LED. By means of the light source  11 , and for the purpose of implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  101  of the light tunnel  108 . By means of the light source  12  selectively connectable for implementing sign light or high-beam headlight, light is made to enter or is irradiated into, respectively, a bottom side of the light tunnel  108  or the portion  110  of the surface of the light passage section  109  facing the light tunnel  108  and configured as a Petzval face. 
       FIG. 4  shows, by way of an enlarged representation, a cut-out of the bend  107  for transition of the light tunnel  108  into the light passage section  109 . The bend  107  is formed by blank—molding and configured as a continuous, curved transition having a radius of curvature of at least 0.15 mm. 
       FIG. 5  shows a cut-out representation of a side view of the headlight lens  100 .  FIG. 6  shows an enlarged cut-out representation of a part of the light tunnel  108  up to the dotted line in  FIG. 5  designated by reference numeral  111 . The upper portion of the part of the light tunnel as shown in  FIG. 6  has been configured as an ellipsoid  150  as represented in  FIG. 7 . Herein, the dotted line  111  approximately corresponds to the axis C-D. For clarifying this embodiment, a part of the cross section of the light tunnel  108  is shown in  FIG. 8  in a manner superimposing the representation of the ellipsoid  150 . For the ellipsoid  150  as represented in  FIG. 7  the following equation applies: 
     
       
         
           
             
               
                 
                   x 
                   2 
                 
                 
                   a 
                   2 
                 
               
               + 
               
                 
                   y 
                   2 
                 
                 
                   b 
                   2 
                 
               
               + 
               
                 
                   z 
                   2 
                 
                 
                   c 
                   2 
                 
               
               - 
               1 
             
             = 
             0 
           
         
       
     
     In this equation
         z is a coordinate in the direction of the optical axis of the light tunnel (A→B);   x is a coordinate orthogonal with respect to the direction of the optical axis of the light tunnel; and   y is a coordinate orthogonal with respect to the direction of the optical axis of the light tunnel and to the x-direction (DC).
 
a, b and, consequently, c have been chosen such that all light beams which pass through focus F1 will concentrate again in focus F2 after mirroring in the surface of the ellipsoid. The course of the beams of light from the light source  11 , which is irradiated into or made to enter, respectively, the light entry face  101 , is made clear by the light beams  121  and  122  depicted in  FIG. 6 . Reference numeral  120  of  FIG. 6  designates the orthogonal of the light entry face  101 . The mutual point of intersection of the orthogonal  120  of the light entry face  101  with the light beams  121  and  122  has been designated by reference numeral  115 . The position of this point of intersection  115  corresponds to focus F1 in  FIG. 7  and  FIG. 8 .
       

       FIG. 9  shows, by way of a side elevation, a motor vehicle headlight  20  to be used alternatively instead of motor vehicle headlight  10 . The motor vehicle headlight  20  comprises a headlight lens  200 . The headlight lens  200  comprises a blank-molded monolithic body made from inorganic glass and comprising a light tunnel  208 , which has a light entry face  201  on one side and, on another side, forms transition into a light passage section  209  (of the blank-molded monolithic body) via a bend  207  curved in three spatial dimensions, which light passage section  209  includes a light exit face  202 , a light entry face  203 , as well as a further light exit face  204 . The headlight lens  200  is configured such that light, which enters the headlight lens  200  through the light entry face  201 , and enters the passage section from the light tunnel  208  in the region of the bend  207 , will exit from the light exit face  204  essentially in parallel to the optical axis of the headlight lens  200 . Herein, the light passage section  209  images the bend  207  as a bright-dark-boundary. A portion of the surface of the light passage section  209  designated by reference numeral  210  and facing the light tunnel  208  is configured as a Petzval surface. 
     The vehicle headlight  20  includes a light source  21  configured as an LED, and a light source  22  configured as an LED. By means of the light source  21 , and for the purpose of implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  201  of the light tunnel  208 . By means of the light source  22  selectively connectable for implementing sign light or drive light, light is made to enter or is irradiated into, respectively, a bottom side of the light tunnel  208  or the portion  210  of the surface of the light passage section  209  facing the light tunnel  208 , which portion is configured as a Petzval face. 
       FIG. 10  shows a further motor vehicle headlight  30  by way of a side elevation and to be used alternatively with regard to motor vehicle headlight  10 . The motor vehicle headlight  30  comprises a headlight lens  300 .  FIG. 11  shows the headlight lens  300  by way of a top view, and  FIG. 12  shows the headlight lens  300  from the rear. The headlight lens  300  comprises a blank-molded monolithic body made from inorganic glass, which body comprises a light tunnel  308 , which has a light entry face  301  on one side and, on the other side, passes over into a light passage section  309  (of the blank-molded monolithic body) via a bend  307  curved in two spatial dimensions, which light passage section  309  includes a light exit face  302 . The headlight lens  300  is configured such that light which enters the headlight lens  300  through the light entry face  301  and, from the light tunnel  308  enters the passage section in the region of the bend  307 , will exit from the light exit face  302  essentially in parallel to the optical axis of the headlight lens  300 . Herein, the light passage section  309  images the bend  307  as a bright-dark-boundary, just as it has been depicted in  FIG. 13 . The surface of the light passage section  309  facing the light tunnel  308  has a portion designated by reference numeral  310  and is configured as a Petzval surface. A rim or edge, for example a circumferential edge, may be provided on the section designated by reference numeral  330  of the surface of the passage section  309 , by means of which edge the headlight lens  300  may be fixedly mounted in a particularly suitable manner. 
     The vehicle headlight  30  includes a light source  31  configured as an LED, and a light source  32  configured as an LED. By means of light source  31 , and for the purpose of implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  301  of the light tunnel  308 . By means of the selectively connectable light source  32  for implementing sign light or drive light, light is made to enter or is irradiated, respectively, into a bottom side of the light tunnel  308  or into the portion  310  configured as a Petzval surface, of the surface of the light passage section  309  facing the light tunnel  308 . 
       FIG. 14  shows a further motor vehicle headlight  40  by way of a side elevation and to be used alternatively with regard to the motor vehicle headlight  10 . The motor vehicle headlight  40  comprises a headlight lens  400 .  FIG. 15  shows the motor vehicle headlight  40  by way of a top view and  FIG. 16  shows the headlight lens  400  from the rear. The headlight lens  400  comprises a blank-molded monolithic body made from inorganic glass, which body includes a light tunnel section  408 A and a light tunnel section  408 B, both of which open out in a light tunnel  408  which, in turn, passes over to a light passage section  409  (of the blank-molded monolithic body) via a bend  407  curved in two spatial directions, which section  409  includes a light exit face  402 , a light entry face  403 , as well as a further light exit face  404 . The light tunnel section  408 A has a light entry face  401 A, and the light tunnel section  408 B has a light entry face  401 B. The headlight lens  400  is configured such that light, which enters the headlight lens  400  through the light entry faces  401 A and  401 B and, in the region of the bend  407  enters the passage section from the light tunnel  408 , will exit from the light exit face  404  essentially in parallel to the optical axis of the headlight lens  400 . Herein, the light passage section  409  images the bend  407  as a bright-dark-boundary. A portion of the surface of the light passage section  409  designated by reference numeral  410  and facing the light tunnel  408  is configured as a Petzval surface. 
     At least in their upper region, the light tunnel sections  408 A and  408 B are configured—in analogy to the explanations relating to  FIG. 6 —as part of an ellipsoid, as has been represented in principle in  FIG. 17 . Herein, reference numeral  150 A designates an ellipsoid associated with the light tunnel section  408 A, and reference numeral  150 B designates an ellipsoid associated with the light tunnel section  408 B. The ellipsoids  150 A and  150 B are—as has been represented in  FIG. 17 —aligned, in relation to each other, such that the respective focuses F2 will lie on top of each other. At the points designated by reference numerals  151 A and  151 B or starting at points  151 A and  150 B, respectively, (in the direction of light propagation or towards the right, respectively), the surface contour of the headlight lens  400  deviates from the contour of an ellipsoid. Herein, the angles α A  and α B  indicate the directions of deviation from the elliptic shape. 
     The motor vehicle headlight  40  includes two light sources, which, in analogy to light source  11  have been configured as LEDs and have not been depicted in  FIG. 14  and  FIG. 16  for the sake of clarity. By means of one of the light sources, and for the purpose of implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  401 A of the light tunnel section  408 A, and by means of the other one of the light sources, and for the purpose of implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  401 B of the light tunnel section  408 B. In addition, a not shown light source may be provided which corresponds to light source  12  with respect to position and performance. 
     In addition, and for implementing a corner light and/or a front fog light (adverse weather lamp) light sources  45  and  46  configured as LEDs are provided, with the light sources  45  and  46  being alternately connectable for implementing the corner light. Herein, a not shown control means is provided for within the motor vehicle  4 , by means of which control means the light source  45  is switched on for the time of driving round a left corner, and light source  46  is switched on for the time of driving round a right corner. For implementing a front fog light, either the light source  46 , alone, is or both light sources  45  and  46  are switched on. 
       FIG. 18  and  FIG. 19  show a motor vehicle headlight  10 A to be used alternatively with regard to motor vehicle headlight  10 . Herein,  FIG. 18  shows the motor vehicle headlight  10 A in a side elevation and  FIG. 19  shows the motor vehicle headlight  10 A in a top view. The motor vehicle headlight  10 A comprises the headlight lens  100  as well as the light source  11 . In addition, for implementing a corner light and/or a front fog light, light sources  15  and  16  configured as LED&#39;s have been provided. It may as well be provided for that, in addition, the light source  12  is implemented within the motor vehicle headlight  10 A. 
     For implementing a corner light, the light sources  15  and  16  may be switched on alternately. In this context, a not shown control means is provided for in the motor vehicle  1 , by means of which the light source  15  may be switched-on for the time of driving round a left corner and light source  16  may be switched on for the time of driving round a right corner. For implementing a front fog light either the light source  16 , only, or both light sources  15  and  16  are switched on. 
       FIG. 20  shows a motor vehicle headlight  10 B (based on headlight lens  100 ) to be used alternately with regard to motor vehicle headlight  10  and including a light source  18  for a drive light function configured as an LED and adapted to be connected, and a light source  19  configured as an LED for a sign light function, wherein the light output of the light source  18  is higher than that of light source  19 . 
       FIG. 21  shows a further motor vehicle headlight  10 C based on headlight lens  100  and to be used alternatively instead of motor vehicle headlight  10 . Herein, additional light sources  1001 ,  1002 ,  1003 ,  1004 ,  1005 , and  1006  are provided along the light tunnel  108 . By means of this arrangement, a higher light output may be achieved. The light sources  1003 ,  1004 ,  1005 ,  1006  or one or several of the light sources  1003 ,  1004 ,  1005 , and  1006  may be provided in context with the motor vehicle headlight  10 B as well. 
       FIG. 22  shows a further motor vehicle headlight  10 D based on headlight lens  100  and alternatively to be used instead of motor vehicle headlight  10 .  FIG. 23  shows the motor vehicle headlight  10 D from the rear, however without the light source  11 . Herein, by means of an LED array  1010  light is made to enter the Petzval-face-configured surface  110  of the passage section  109 , the components of which array being adapted to be individually controlled or connected, respectively. 
       FIG. 24  shows a top view of an example of embodiment for an alternatively applicable motor vehicle headlight arrangement  30 A. The motor vehicle headlight arrangement  30 A includes the partial headlights  3001 ,  3002 ,  3003 , and  3004 , which have headlight lenses configured in analogy to headlight lens  300 , each, however, having a circumferential rim or edge  331  with differently configured bends, so that the bright-dark-boundary  3005  represented in  FIG. 25  will be brought about. It may be provided for that the partial headlights  3001 ,  3002 ,  3003 , and  3004  may have LED arrays corresponding to LED array  1010 . 
     It may be provided for that instead of the partial headlight  3001  the motor vehicle headlight  10 , the motor vehicle headlight  10 A, the motor vehicle headlight  10 B, the motor vehicle headlight  10 C, the motor vehicle headlight  10 D, the motor vehicle headlight  10 E, the motor vehicle headlight  20 , the motor vehicle headlight  40 , or the motor vehicle headlight  80  will be used, wherein the respective bends correspond to the bend of partial headlight  3001 . It may be provided for that instead of the partial headlight  3002  the motor vehicle headlight  10 , the motor vehicle headlight  10 A, the motor vehicle headlight  10 B, the motor vehicle headlight  10 C, the motor vehicle headlight  10 D, the motor vehicle headlight  10 E, the motor vehicle headlight  20 , the motor vehicle headlight  30 B, the motor vehicle headlight  40 , or the motor vehicle headlight  80  will be used, the associated bends corresponding to the bend of partial headlight  3002 . It may be provided for that instead of the partial headlight  3003  the motor vehicle headlight  10 , the motor vehicle headlight  10 A, the motor vehicle headlight  10 B, the motor vehicle headlight  10 C, the motor vehicle headlight  10 D, the motor vehicle headlight  10 E, the motor vehicle headlight  20 , the motor vehicle headlight  30 B, the motor vehicle headlight  40 , or the motor vehicle headlight  80  will be used, the associated bends corresponding to the bend of partial headlight  3003 . It may be provided for that instead of the partial headlight  3004  the motor vehicle headlight  10 , the motor vehicle headlight  10 A, the motor vehicle headlight  10 B, the motor vehicle headlight  10 C, the motor vehicle headlight  10 D, the motor vehicle headlight  10 E, the motor vehicle headlight  20 , the motor vehicle headlight  30 B, the motor vehicle headlight  40 , or the motor vehicle headlight  80  will be used, the associated bends corresponding to the bend of partial headlight  3004 . 
     The optical axes  3011 ,  3012 ,  3013 , and  3014  of the partial headlights  3001 ,  3002 ,  3003 , and  3004 , respectively, lie in a horizontal plane and are slightly inclined therein with respect to each other so that the partial headlight  3001  illuminates essentially the −8°-region, the partial headlight  3002  illuminates essentially the −4° region, the partial headlight  3003  illuminates essentially the 4° region and the partial headlight  3004  illuminates essentially the 8° region, respectively, (cf.  FIG. 25 ). It may be provided for that the partial headlights  3001 ,  3002 ,  3003 , and  3004  be fixedly connected with each other within a module. It may be provided for that the partial headlights  3001 ,  3002 ,  3003 , and  3004  are disposed in a mutual housing. It may also be provided for that the partial headlights  3001 ,  3002 ,  3003 , and  3004 , as well as further corresponding partial headlights are disposed along the circumference of a geometrical figure, for example along a circle. 
       FIG. 26  shows a motor vehicle headlight arrangement  50  by way of a top view and to be used alternatively with regard to motor vehicle headlight  10 . The motor vehicle headlight arrangement  50  includes partial headlights designated by reference numerals  50 A and  50 B. The partial headlight  50 A comprises a headlight lens  500 A. The headlight lens  500 A comprises a blank-molded monolithic body of inorganic glass and including a light tunnel  508 A, which has a light entry face  501 A on one side and, on another side (on the bottom side of the headlight lens  500 A), passes over into a light passage section  509 A (of the blank-molded monolithic body) via a bend curved in two spatial dimensions, which light conductive section  509 A includes a light exit face  502 A. The headlight lens  500 A is configured such that light, which enters the headlight lens  500 A through the light entry face  501 A, and from the light tunnel  508 A enters the passage section in the region of the bend, will exit from the light exit face  502 A essentially in parallel to the optical axis  55 A of the headlight lens  500 A. Herein, the light passage section  509 A images the bend as a bright-dark-boundary  550 , as has been represented in  FIG. 37 . Herein, the partial headlight  50 A illuminates essentially the region between −20° and 0°. A portion of the surface of the light passage section  509 A, which portion is facing the light tunnel  508 A and has been designated by reference numeral  510 A, is configured as a Petzval surface. The partial headlight  50 A includes a light source  51 A configured as an LED. For implementing a dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  501 A of the light tunnel  508 A by means of the light source  51 A. 
     The partial headlight  50 B comprises a headlight lens  500 B. The headlight lens  500 B comprises a blank-molded monolithic body made from inorganic glass, which comprises a light tunnel  508 B, which has a light entry face  501 B on one side and, on another side (on the bottom side of the headlight lens  500 B) forms transition into a light passage section  509 B (of the blank-molded monolithic body) via a bend curved in two spatial dimensions, which light passage section  509 B includes a light exit face  502 B. The headlight lens  500 B is configured such that light, which enters the headlight lens  500 B through the light entry face  501 B, and from the light tunnel  508 B enters the passage section in the region of the bend, will exit from the light exit face  502 B essentially in parallel to the optical axis  55 B of the headlight lens  500 B. Herein, the light passage section  509 B images the bend as a bright-dark-boundary  550 , as has been represented in  FIG. 27 . Herein, the partial headlight  50 A illuminates essentially the region between 0° and 20°. A portion of the surface of the light passage section  509 B, which portion is facing the light tunnel  508 B and has been designated by reference numeral  510 B, is configured as a Petzval surface. The partial headlight  50 B includes a light source  51 B configured as an LED. For implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  501 B of the light tunnel  508 B by means of the light source  51 B. The optical axes  55 A and  55 B lie in one horizontal plane and, in this plane, are inclined by 25° with regard to each other. 
       FIG. 28  shows, by way of a top view, a further motor vehicle headlight  60  alternatively to be used instead of motor vehicle headlight  10 . The motor vehicle headlight  60  comprises a blank-molded monolithic body of inorganic glass, which body comprises a headlight lens part  600 A, a headlight lens part  600 B, and a headlight lens part  600 C. 
     The headlight lens part  600 A comprises a light tunnel  608 A, which has a light entry face  601 A on one side and, on another side (on the bottom side of the headlight lens part  600 A), passes over (forms transition) into a light passage or conductive section  609 A of the headlight lens part  600 A via a bend curved in two spatial dimensions, which light passage section  609 A includes a light exit face  602 A. The headlight lens part  600 A is configured such that light, which enters the headlight lens  600 A through the light entry face  601 A, and from the light tunnel  608 A enters the passage section in the region of the bend, will exit from the light exit face  602 A essentially in parallel to the optical axis  65 A of the headlight lens part  600 A. Herein, the light passage section  609 A images the bend as a bright-dark-boundary. A portion of the surface of the light passage section  609 A, which portion is facing the light tunnel  608 A and has been designated by reference numeral  610 A, is configured as a Petzval face. The motor vehicle headlight  60  includes a light source  61 A configured as an LED, by means of which, for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  601 A of the light tunnel  608 A. 
     The headlight lens part  600 B comprises a light tunnel  608 B, which has a light entry face  601 B on one side and, on another side (on the bottom side of the headlight lens part  600 B), passes over (forms transition) into a light passage or conductive section  609 B of the headlight lens part  600 B via a bend curved in two spatial dimensions, which light passage section  609 B includes a light exit face  602 B. The headlight lens part  600 B is configured such that light, which enters the headlight lens  600 B through the light entry face  601 B, and, in the region of the bend, from the light tunnel  608 B enters the passage section will exit from the light exit face  602 B essentially in parallel to the optical axis  65 B of the headlight lens part  600 B. Herein, the light passage section  609 B images the bend as a bright-dark-boundary. A portion of the surface of the light passage section  609 B, which portion is facing the light tunnel  608 B and has been designated by reference numeral  610 B, is configured as a Petzval surface. The motor vehicle headlight  60  includes a light source  61 B configured as an LED, by means of which, for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  601 B of the light tunnel  608 B. 
     The headlight lens part  600 C comprises a light tunnel  608 C, which has a light entry face  601 C on one side and, on another side (on the bottom side of the headlight lens part  600 C), passes over (forms transition) into a light passage section  609 C of the headlight lens part  600 C via a bend curved in two spatial dimensions, which light passage section  609 C includes a light exit face  602 C. The headlight lens part  600 C is configured such that light, which enters the headlight lens  600 C through the light entry face  601 C, and, in the region of the bend, from the light tunnel  608 C enters the passage section will exit from the light exit face  602 C essentially in parallel to the optical axis  65 C of the headlight lens part  600 C. Herein, the light passage section  609 C maps the bend as a bright-dark-boundary. A portion of the surface of the light passage section  609 C, which portion is facing the light tunnel  608 C and has been designated by reference numeral  610 C, is configured as a Petzval surface. The motor vehicle headlight  60  includes a light source  61 C configured as an LED, by means of which, for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  601 C of the light tunnel  608 C. 
     The optical axis  65 A lies in a first plane, which is essentially horizontal. The optical axis  65 B lies in a second essentially horizontal plane. The optical axis  65 C lies in a third essentially horizontal plane. The first plane, the second plane, and the third plane extend essentially in parallel to each other. The optical axis  65 A, moreover, lies in a first vertical plane. The optical axis  65 B, moreover, lies in a second vertical plane. The optical axis  65 C, moreover, lies in a third vertical plane. The first vertical plane is inclined by 0.5° with respect to the second vertical plane. The first vertical plane is inclined by 1° with respect to the third vertical plane. The second vertical plane is inclined by 0.5° with respect to the third vertical plane. 
       FIG. 29  shows, by way of a top view, a further motor vehicle headlight  70  alternatively to be used instead of motor vehicle headlight  10 . The motor vehicle headlight  70  comprises a blank-molded monolithic body of inorganic glass, which body comprises a headlight lens part  700 A, a headlight lens part  700 B, and a headlight lens part  700 C. 
     The headlight lens part  700 A comprises a light tunnel  708 A, which has a light entry face  701 A on one side and, on another side, transits into a light passage section  709 A of the headlight lens part  700 A via a bend  707 A curved in two spatial dimensions, which light passage section  709 A includes a light exit face  702 A. The headlight lens part  700 A is configured such that light, which enters the headlight lens  700 A through the light entry face  701 A, and from the light tunnel  708 A enters the passage section in the region of the bend  707 A, will exit from the light exit face  702 A essentially in parallel to the optical axis of the headlight lens part  700 A. Herein, the light passage section  709 A images the bend  707 A as a bright-dark-boundary. A portion of the surface of the light passage section  709 A, said surface facing the light tunnel  708 A, and which portion has been designated by reference numeral  710 A, is configured as a Petzval face. The motor vehicle headlight  70  includes a light source  71 A configured as an LED, by means of which, for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  701 A of the light tunnel  708 A. 
     The headlight lens part  700 B comprises a light tunnel (hidden in  FIG. 29  by headlight lens part  700 A), which has a light entry face on one side (hidden in  FIG. 29  by headlight lens part  700 A) and, on another side (on the bottom side of the headlight lens part  700 B), forms transit into a light passage section  709 B of the headlight lens part  700 B via a bend curved in two spatial dimensions, which light passage section  709 B includes a light exit face  702 B. The headlight lens part  700 B is configured such that light, which enters the headlight lens part  700 B through the light entry face, and, in the region of the bend, from the light tunnel enters the passage section will exit from the light exit face  702 B essentially in parallel to the optical axis of the headlight lens part  700 B. Herein, the light passage section  709 B images the bend as a bright-dark-boundary. A portion (hidden in  FIG. 29  by headlight lens part  700 A) of the surface of the light passage section  709 B, which surface is facing the light tunnel, is configured as a Petzval surface. The motor vehicle headlight  70  includes a light source (hidden in  FIG. 29  by headlight lens part  700 A), configured as an LED, by means of which, for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face of the light tunnel. 
     The headlight lens part  700 C comprises a light tunnel  708 C, which has a light entry face  701 C on one side and, on another side (on the bottom side of the headlight lens part  700 C), forms transition into a light passage section  709 C of the headlight lens part  700 C via a bend  707 C curved in two spatial dimensions, which light passage section  709 C includes a light exit face  702 C. The headlight lens part  700 C is configured such that light, which enters the headlight lens  700 C through the light entry face  701 C, and, in the region of the bend  707 C, from the light tunnel  708 C enters the passage section will exit from the light exit face  702 C essentially in parallel to the optical axis of the headlight lens part  700 C. Herein, the light passage section  709 C images the bend  707 C as a bright-dark-boundary. A portion of the surface of the light passage section  709 C, said surface facing the light tunnel  708 C, which portion has been designated by reference numeral  710 C, is configured as a Petzval surface. The motor vehicle headlight  70  includes a light source  71 C configured as an LED, by means of which, for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  701 C of the light tunnel  708 C. 
       FIGS. 30 and 31  show a motor vehicle headlight  80 , to be used alternatively with regard to motor vehicle headlight  10 , however, without any housing, fittings and energy supply. Herein,  FIG. 31  shows the motor vehicle headlight  80  by way of a side elevation and  FIG. 30  shows the motor vehicle headlight  80  by way of an oblique top view.  FIG. 32  shows the headlight lens  800  from above, by way of a top view, and  FIG. 33 ,  FIG. 34 , and  FIG. 35  show the headlight lens  800  by way of a perspective representation from the rear. 
     The motor vehicle headlight  80  comprises a light source  81  and a headlight lens  800 . The motor vehicle headlight  80  may be complemented by further light sources, as have been disclosed in  FIG. 2 ,  FIG. 14 ,  FIG. 18 ,  FIG. 20 ,  FIG. 21  and/or  FIG. 22 . The headlight lens  800  comprises a blank-molded monolithic body of inorganic glass, which body comprises a light tunnel  808 , which has a light entry face  801  on one side and, on the other side, passes over into a light passage section  809  (of the blank-molded monolithic body) via a bend  807  curved in two spatial dimensions, which light passage section  809  includes a segmented light exit face  802 , whose segments have been designated by reference numerals  802 A,  802 B, and  802 C. 
     The headlight lens  800  is configured such that light, which enters the headlight lens  800  through the light entry face  801 , and, in the region of the bend  807 , from the light tunnel  808  enters the light passage section will exit from the light exit face  802  essentially in parallel to the optical axis of the headlight lens  800 . Herein, the light passage section  809  images the bend  807  as a bright-dark-boundary, as has been represented in  FIG. 36 , wherein by means of the light source  81 , for implementing dipped-beam headlight, light is irradiated into or made to enter, respectively, the light entry face  801  of the light tunnel  808 . 
     The light tunnel  808  has a region of transition  808 A, in which the surface restricting the light tunnel  808  upwardly in the direction towards the light passage section  809  rises and in which the surface restricting the light tunnel  808  downwardly extents horizontally or in parallel, respectively, regarding the optical axis of the headlight lens  800 . In the rearward area of the light tunnel  808  the light tunnel  808  includes two indentations  881  and  882  on its upwardly restricting surface, which indentations extend essentially in the longitudinal direction of the light tunnel  808 , or essentially in parallel to the optical axis of the light tunnel  808 , or essentially in parallel to the optical axis of the light passage section  809 , or essentially in parallel to the optical axis of the light exit face  802 , respectively. In this portion, the light tunnel  808  comprises three segments  871 ,  872 , and  873 , which have an orientation in its longitudinal direction, which segments are configured or separated, respectively, by the indentations  881  and  882 . The segments  871 ,  872 , and  873  of the light tunnel  808  start at the light entry face  801  and extend up to the region of transition  808 A. On their upper sides, the segments  871 ,  872 , and  873  comprise a surface, which essentially corresponds to a part of the surface of an ellipsoid. 
       FIG. 37  shows a motor vehicle headlight  10 E by way of a side elevation and to be used alternatively with regard to motor vehicle headlight  10 , which motor vehicle headlight  10 E comprises a headlight lens  100 E modified with respect to headlight lens  100 , wherein the light tunnel  108  includes a region of transition  108 A starting as from line  111  (cf.  FIG. 5 ), in which region the surface restricting the light tunnel  108  upwardly rises in the direction towards the light passage section  109 . Herein, the surface restricting the light tunnel  108  upwardly includes, within the region of transition  108 A, a concavely curved area having a radius of curvature of at least 20 mm as well as a point of inflection (a turning or reversal point)  1081 . The region of transition  108 A is configured such that the surface restricting the light tunnel  108  upwardly transits without any bend or without any step into the surface restricting the light passage section  109  upwardly. The motor vehicle headlight  10 E may be completed (complemented) by further light sources as have been disclosed in  FIG. 14 ,  FIG. 18 ,  FIG. 20 ,  FIG. 21 , and/or  FIG. 22 . 
       FIG. 38  shows a motor vehicle headlight  30 B by way of a side elevation and to be used alternatively with regard to motor vehicle headlight  10 , which motor vehicle headlight  30 B comprises a headlight lens  300 E modified with regard to headlight lens  300 , wherein the light tunnel  308  includes a region of transition  308 A in which the surface restricting the light tunnel  308  upwardly rises in the direction towards the light passage section  309 . Herein, the surface restricting the light tunnel  308  upwardly includes, within the region of transition  308 , a concavely curved area having a radius of curvature of at least 20 mm as well as a (turning or reversal) point of inflection  3081 . The region of transition  308 A is configured such that the surface restricting the light tunnel  308  upwardly transits into the surface, which restricts the light passage section  309  upwardly, without any bend or without any step. The motor vehicle headlight  30 B may be completed (complemented) by further light sources as have been disclosed in  FIG. 14 ,  FIG. 18 ,  FIG. 20 ,  FIG. 21 , and/or  FIG. 22 . 
     The headlight lens  500 A, the headlight lens  500 B, the headlight lens part  600 A, the headlight lens part  600 B, the headlight lens part  600 C, the headlight lens part  700 A, the headlight lens part  700 B, and/or the headlight lens part  700 C may be configured in analogy with headlight lenses  100 ,  100 E,  300 ,  300 B,  400 , and  800 , respectively. 
     Statements or terms regarding the orientation such as “upward(ly)”, “rising” or “horizontal(ly)” relate to normal (designated or intended) operation of a (motor) vehicle headlight. Such statements particularly refer to a (motor) vehicle headlight installed in a horizontally positioned motor vehicle. The elements, distances and angles in the figures have been represented in consideration of simplicity and clearness and not necessarily to scale. For example, the orders of magnitude of some of the elements, distances and angles have been exaggerated with respect to other elements, distances and angles in order to enhance comprehension of the examples of embodiments of the present invention. Also, in order to improve comprehension of the examples of embodiment of the present invention, the motor vehicle headlights have been represented without any housings, fittings, and energy supply.

Technology Classification (CPC): 5