Abstract:
A method for producing a vehicle headlamp lens having at least one light entry surface and at least one optically effective light exit surface wherein glass, (for example, in gob and/or liquid form) is blank-pressed between a first mold and at least one second mold to form a one-piece member comprising a first partial light conducting part and a light tunnel, which transitions into the first partial light conducting part by means of a bend. The glass is, for example, drawn into the second mold by means of an under pressure and the first partial light conducting part is at least partially over molded with transparent plastic to form a second partial light conducting part so that the first partial light conducting part and the second partial light conducting part form and/or shape a light conducting part for imaging the bend as a light-shadow line.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. nationalization under 35 U.S.C. §371 of International Application No. PCT/EP2013/001160, filed Apr. 18, 2013, which claims priority to German Application No. 102012009596.1, filed May 15, 2012. 
     FIELD OF THE INVENTION 
     The invention also relates to a headlight lens, including at least one light tunnel and at least one light passage section. 
     BACKGROUND INFORMATION 
     DE 10 2004 043 706 A1 discloses an optical system for a motor vehicle headlight for dispersing a beam of light rays of an illuminant, with an optical primary element having an optical face including a break or discontinuity and extending along a line, being provided, wherein the optical face is configured to be 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 that at least one of the partial beams of light rays has a sharp boundary edge. Moreover, the optical system comprises an optical secondary element for imaging the sharp boundary edge onto a predetermined bright (also known as “light-”)-dark-boundary. 
     EP 1 357 333 A2 discloses a light source device for a vehicle light which has an element irradiating semiconductor light, which element is arranged on an optical axis of the light source device and irradiates its light essentially in an orthogonal direction with regard to the optical axis. 
     DE 195 26 512 A1 discloses an illumination device for vehicles, wherein a light conductor of light-transmissive material having a predetermined light refractory index is arranged between the light exit end of an optical lead and a light entry end of a lens body. Herein, the light conductor is configured such that it covers the total surface of the exit light end of the optical lead and has a light exit face which is configured such that it is suited for forming an illumination pattern. 
     DE 102 52 228 A1 discloses a headlight for a motor vehicles including a light source as well as a light termination body associated with the light source and having a light entry face for making light irradiated from the light source enter, and a light exit face as well as a lens which cooperates with the light exit face and is arranged in the light irradiating direction following the light termination body. 
     Further illumination means in context with vehicles are disclosed by DE 42 09 957 A1, DE 41 21 673 A1, DE 43 20 554 A1, DE 10 2009 008 631 A1, U.S. Pat. No. 5,257,168, DE 103 15 131 A1, DE 20 2004 005 936, DE 203 20 546 U1, DE 10 2004 048 500 A1, and U.S. Pat. No. 5,697,690. 
     It is, for example, 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 vehicles. It is a still further object of the invention to suggest a vehicle having particularly compact dimmed headlights. 
     SUMMARY 
     The aforementioned object is achieved by a headlight lens for a vehicle headlight, for example for motor vehicle headlight, including at least one (for example optically operative) light entry face and e.g. at least one optically operative light exit face, wherein the headlight lens comprises a light tunnel, which, via a bend, forms transition into a first partial light passage section of a light passage section for imaging the bend as a bright-dark-boundary, wherein the light tunnel and the first partial light passage section of the light passage section form a for example blank-molded, monolithic body of glass or are part of a for example blank-molded, monolithic body, and wherein the light passage section includes at least one second partial light passage section of transparent, for example amorphous, plastic, which section at least partially encloses the first partial light passage section and/or is fixedly connected to the first partial light passage section. 
     Herein, it is, in particular, provided for that the first partial light passage section is injection molded around by the second partial light passage section or that the second partial light passage section is added by injection-molding to the first partial light passage section. It is, in particular, provided for that the glass part or element is not injection-molded around in the area of the bend or is not enclosed, respectively. 
     In a suitable process for manufacturing the aforementioned headlight lens, at first, a glass part or element (glass body) is blank-molded, in particular from hot gob or from the molten mass, particularly under complete mold contact, which glass part comprises the light tunnel and the first partial light passage section. Subsequently, the glass part is cooled-down and is then injection-molded around by transparent plastic material for forming the second partial light passage section or, respectively, transparent plastic material is then added-on to the first partial light passage section by injection molding for forming the second partial light passage section. 
     It is, for example, provided for that the glass part, body, or element has a coating as it has been disclosed in DE 11 2007 000 189 A5, for example. Such a coating is, in particular, brought about before the injection molding-around takes place. It is, for example, provided for that the coating comprises a concentration of aluminum, which is larger than a concentration of aluminum in the interior of the glass part, and/or than a concentration of sodium which is smaller than a concentration of sodium in the interior of the glass part. It is, for example, provided for that the glass part, body, or element externally (on its surface) comprises a concentration of aluminum which is larger than a concentration of aluminum in the interior of the glass part, and/or a concentration of sodium which is smaller than a concentration of sodium in the interior of the glass part/body. It is, for example, provided for that during cooling down the glass part/body is (over) floated by gas containing sulfur, chlorine, fluor, iron and/or aluminum, wherein the gas, for example, comprises HCl or CF 4  or AlCl 3    
     An optically operative (or effective) light entry (sur)face and/or an optically operative light exit (sur)face, respectively, is an optically effective face. An optically effective (sur)face is, in particular, a (sur)face of the transparent body, at which face, when using the headlight lens according to its purpose, light will be refracted. An optically operative face is, in particular, a face at which, when using the headlight lens according to its purpose, the direction of light which passes through this face will be changed. 
     Glass is particularly inorganic glass or silicate glass. Glass is for example glass as described in Document 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 face 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 light exit face 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 (in particular 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 for example a light guide or light conductor. It is, for example, provided for that total reflection is achieved at the longitudinal surfaces of the light tunnel. It is, for example, provided for that the longitudinal surfaces of the light tunnel are adapted for total reflection. It is, for example, provided for that total reflection is achieved by/at the surfaces of the light tunnel essentially oriented in the direction of the optical axis of the light tunnel. It is, for example, provided for that the surfaces of the light tunnel essentially oriented in the direction of the optical axis of the light tunnel are provided for total reflection. A light tunnel, for example, tapers in the direction of its light entry face. A light tunnel, for example, tapers in the direction of its light entry face by at least 3°. A light tunnel, for example, tapers in the direction of its light entry face by at least 3° with respect to its optical axis. A light tunnel, tapers for example, at least partially in the direction of its light entry face. A light tunnel, e.g., tapers at least partially in the direction of its light entry face by at least 3°. A light tunnel, tapers for example, 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. It is, for example, provided for that the surface of the headlight lens has no break or discontinuity in the bend, but rather a curve or curvature. It is, for example, 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. In an expedient embodiment the radius of curvature is no more than 0.25 mm, for example, no more than 0.15 mm, for example 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. It is, for example, provided for that the surface of the headlight lens is blank-molded in the region of the bend. The bend is, for example, suited for being imaged by means of light as a bright-dark-boundary, which light is made to enter or to be irradiated into the light entry face. 
     In a further embodiment the first partial light passage section includes a bulge embedded in the second partial light passage section. In the sense of the invention, a bulge (convexity) is, for example, a flange or bead, for example a circumferential flange or bead. 
     In a further embodiment the first partial light passage section includes a curved boundary (sur)face or interface towards the second partial light passage section, the curvature being for example convex or configured according to a free shape, respectively. In a further embodiment the first partial light passage section includes a curved, optically operative boundary (sur)face or interface towards the second partial light passage section, the curvature being for example convex or configured according to a free shape, respectively. An optically operative boundary face is, for example, a boundary face at which light reflection will occur when the headlight lens is being used according to its purpose. An optically operative boundary face is, for example, a boundary face at which the direction of light, which passes through this boundary face will be changed when the headlight lens is being used according to its purpose. 
     In a further embodiment the light entry face is associated with the light tunnel or it is part of the light tunnel, respectively. In a further embodiment the light exit face is associated with the light passage section or with the second light passage section or it is part of the second partial light passage section, respectively. In a further embodiment the light tunnel is arranged 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. It is, for example, provided for that light entering the headlight lens 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. It is, for example, provided for that light entering the headlight lens through the light entry face will exit from the light exit face at an angle of between −20° and 20° relative to the optical axis. It is, for example, provided for that light entering the headlight lens 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. It is, for example, provided for that light entering the headlight lens 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 includes an opening angle of at least 90°. In a further expedient embodiment the bend includes an opening angle of no more than 150°. In a further favourable embodiment the bend is arranged 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 expedient embodiment the light entry face is inclined with respect to the optical axis of the light passage section at an angle of between 5° and 70°, for example at 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 expedient 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 further embodiment the light tunnel comprises a region on its surface, for which the following applies: 
     
       
         
           
             
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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, having a radius of curvature of between 5 mm and 100 mm. In a further embodiment the bend is curved, in its longitudinal extension, corresponding to a Petzval curve (also termed Petzval [sur]face). 
     In a further expedient 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 further embodiment 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 expedient embodiment the first direction is orthogonal to the second direction. In a 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 is configured as a Petzval face. In a 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 light passage section or the second partial light passage section, respectively, has a further light exit face as well as a further light entry face. In a further expedient 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 headlight lens through the further light exit face and after having entered the headlight lens 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 headlight lens through the further light exit face and without having entered the headlight lens through the further light entry face. In a further expedient 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 headlight lens through the further light exit face and after having entered the headlight lens through the further light entry face. In a further embodiment it is provided for that light which enters the headlight lens through the light entry face and enters the passage section from the light tunnel in the region of the bend will either exit from the headlight lens from the further light exit face and enter the further light entry face of the headlight lens as well as it will exit from the headlight lens from the light exit face, or it will exit directly from the light exit face (without exiting from the headlight lens through the further light exit face and without entering the further light entry face of the headlight lens). 
     The aforementioned object is moreover achieved by a vehicle headlight, for example a motor vehicle headlight, wherein the vehicle headlight includes a headlight lens comprising one or several of the aforementioned features as well as a light source for making light enter the light entry face. In an embodiment the light source includes 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 a plane/planar luminous field. The light source may also include light element chips as have been disclosed in DE 103 15 131 A1. A light source may as well be a laser. A suitable laser is disclosed in ISAL 2011 Proceedings, page 271ff. 
     In a further expedient 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, respectively. A secondary optic is in particular an optical element for aligning light separated from and/or subordinated with regard to the headlight lens. A secondary optic is in particular no cover or 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 bright-dark-boundary lies in the lower region of the light tunnel. 
     In a 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 first light tunnel and/or the light passage section amounts to no more than 10 cm. 
     One or several further light sources may be provided for whose light is made to enter or irradiate into, respectively, the passage section and/or a part of the light tunnel for implementing signlight, high-beam headlight and/or curving light. For making such additional light enter the light tunnel, it is, in particular, provided for that this is performed in that half of the light tunnel which is closer to the light passage section and/or in which the light entry face is not provided. 
     The aforementioned object is, moreover, achieved by a method for manufacturing a headlight lens—for example comprising one or several of the aforementioned features—including at least one light entry face and at least one optically operative light exit face, wherein glass (for example from the melting/molten mass or in a liquid state, respectively) is blank-molded between a first mold and at least a second mold to form a monolithic body (in particular under complete contact of the molds), which body comprises a first partial light passage section and a light tunnel which, by way of a bend, forms transition into the first partial light passage section, wherein it is for example provided for that the glass is drawn into the second mold by means of depression (under pressure), and wherein, for forming a second partial light passage section, the first partial light passage section is at least partially injection-added or injection-surrounded such by transparent plastic that the first partial light passage section and the second partial light passage section configure or form, respectively, a light passage section for imaging the bend as a bright-dark-boundary. In an expedient embodiment of the invention, the depression amounts to at least 0.5 bar. In a further embodiment of the invention, the depression corresponds, for example, to vacuum. In a further expedient embodiment the glass, immediately before molding, has a viscosity of no more than 10 45  dPas. 
     The aforementioned object is, moreover, achieved by a headlight lens for a vehicle headlight, for example for a motor vehicle headlight, said headlight lens including at least one optically operative light exit face and at least one optically operative second light exit face, wherein the headlight lens comprises a first light tunnel with a first light entry face, which light tunnel, via a first bend, forms transition into a first partial light passage section of a light passage section, for imaging the first bend as a bright-dark-boundary, wherein the headlight lens comprises a second light tunnel with at least one second light entry face, which second light tunnel, via a second bend, forms transition into a second partial light passage section of the light passage section, for imaging the second bend as a bright-dark-boundary, wherein the first light tunnel and the first partial light passage section of the light passage section form a for example blank-molded, monolithic body of glass (first glass part, element, or body) or are part of an for example blank-molded, monolithic body of glass, wherein the second light tunnel and the second partial light passage section of the light passage section form a for example blank-molded, monolithic body of glass (second glass part, element, or body) or are part of an for example blank-molded, monolithic body of glass, and wherein the light passage section includes at least one third partial light passage section of transparent, for example amorphous, plastic material, which third partial light passage section encloses the first partial light passage section and the second partial light passage section at least partially and/or is fixedly connected to the first partial light passage section and the second partial light passage section. The light entry faces, the light exit faces, the light tunnel and the bends may be configured for example corresponding to the aforementioned embodiments. It is, for example, provided for that the first and the second partial light passage sections are injection molded-around by the third partial light passage section or that the third partial light passage section is added-on by injection molding to the first partial light passage section and/or to the second partial light passage section. It is, for example, provided for that the glass parts (elements, bodies), in the region of the bend, are not injection molded-around, or are not enclosed, respectively. 
     In an embodiment the first partial light passage section has a boundary face towards the third partial light passage section, which boundary face is curved, for example, convexly or according to a free shape, respectively. In a further embodiment the first partial light passage section has a an optically operative boundary face towards the third partial light passage section, which boundary face is curved, for example convexly or according to a free shape, respectively. 
     In a further embodiment the second partial light passage section has a boundary face towards the third partial light passage section, which boundary face is curved, for example, convexly or according to a free shape, respectively. In a further embodiment the second partial light passage section has an optically operative boundary face towards the third partial light passage section, which boundary face is curved, for example convexly or according to a free shape, respectively. 
     In an appropriate process for manufacturing the aforementioned headlight lens, at first, for example taken from the molten mass, and, in particular, under complete mold contact, a first glass part (glass body) is blank-molded, which comprises the first light tunnel and the first partial light passage section, as well as a second glass part (glass body) is blank-molded, which comprises the second light tunnel and the second partial light passage section. Subsequently, both glass parts are cooled-down and are then mutually injection molded-around, or enclosed by transparent plastic material for forming the third partial light passage section. It may also be provided for that transparent plastic material is added-on by injection molding (or cast-on) to the first partial light passage section and to the second partial light passage section. 
     It is, for example, provided for that the glass parts (bodies or elements) have coatings as it has been disclosed in DE 11 2007 000 189 A5, for example. Such a coating is, for example, brought about before the injection molding-around takes place. It is, for example, provided for that the coating comprises a concentration of aluminum which is larger than a concentration of aluminum in the interior of the glass parts, and/or than a concentration of sodium which is smaller than a concentration of sodium in the interior of the glass parts. It is, for example, provided for that the glass parts or elements externally (on their surfaces) comprise a concentration of aluminum which is larger than a concentration of aluminum in the interior of the glass parts, and/or a concentration of sodium which is smaller than a concentration of sodium in the interior of the glass parts. It is, for example, provided for that during cooling-down the glass parts are (over)floated by gas containing sulfur, chlorine, fluor, iron and/or aluminum, wherein the gas, for example, comprises HCl or CF 4  or AlCl 3    
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  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 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 for 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 cross-sectional side view of the headlight lens according to  FIG. 2 ; 
         FIG. 30  shows a cross-sectional side view of the headlight lens according to  FIG. 10 ; 
         FIG. 31  shows a cross-sectional top view of the headlight lens according to  FIG. 28 ; and 
         FIG. 32  shows a cross-sectional top view of an alternative embodiment of the headlight lens according to  FIG. 28 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an example of embodiment of a motor vehicle  1  having 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, for example, 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 light tunnel  108 , which, on its one side, has a light entry face  101  and, on another side, passes/transits into a light passage (or conductive) section  109  (of the headlight lens) 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 (or light)-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 . 
       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  being 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 (overlaying) 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 (AB);   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 or rays 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 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 light tunnel  208 , which has a light entry face  201  on one side and, on the other side, forms transition into a light passage section  209  (of the headlight lens) via a bend  207  curved in the 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 from the light tunnel  208  enters the passage section 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 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 high-beam headlight, 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  210  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 light tunnel  308 , which has a light entry face  301  on one side and, on the other side, passes over into a light passage (conductive) section  309  (of the headlight lens) 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 light-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 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 fixed in a for example appropriate 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 the 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 light source  32  selectively connectable for implementing sign light or high-beam headlight, light is made to enter or is irradiated, respectively, into a bottom side of the light tunnel  308  or into the Petzval-surface—configured portion  310  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 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 light tunnel section  408 A and a light tunnel section  408 B, which open out in a light tunnel  408  which, in turn, passes over to a light passage section  409  (of the headlight lens) 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 includes 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 light-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—taken 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 alternatively connectable for implementing the corner light. Herein, a not shown control is provided for within the motor vehicle  4 , by means of which control 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 light source  46 , alone, or both light sources  45  and  46  are switched on. 
       FIG. 18  and  FIG. 19  show a motor vehicle headlight lens  10 A to be used alternatively with regard to motor vehicle headlight  10 . Herein,  FIG. 18  shows the motor vehicle headlight lens  10 A in a side elevation and  FIG. 19  shows the motor vehicle headlight lens  10 A in a top view. The motor vehicle headlight lens  10  A comprises the headlight lens  100  as well as the light source  11 . In addition, for implementing a corner (or curve) 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 alternatively. In this context, a non-shown control 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 alternatively 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 ,  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 ,  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 has 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  20  or the motor vehicle headlight  40  will be used, the associated bends corresponding 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  20  or the motor vehicle headlight  40  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  20 , or the motor vehicle headlight  40  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  20  or the motor vehicle headlight  40  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 arranged 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 arranged 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 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), transits into a light passage or conductive section  509 A (of the headlight lens) via a bend curved in two spatial dimensions, which light conductive section 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. 27 . 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 and including 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 headlight lens) via a bend curved in two spatial dimensions, which light passage section 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 headlight lens  60  comprising 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) forms transit into a light passage 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 light-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), forms transit 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 conductive 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 light-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 A, 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), transits 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 light-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 the headlight lens according to  FIG. 2  by way of a lateral cross sectional elevation. The headlight lens  100  comprises a blank-molded monolithic body  1120  (=glass part) of 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  1120  comprises the light tunnel  108 , as well as a partial light passage section  1121 . The partial light passage section  1121  is partially injection molded-around by transparent plastic material for molding a further partial light passage section  1122 . The partial light passage section  1121  and the partial light passage section  1122  form the light passage section  109 . 
     The transparent plastic material is, for example, Makrolon LED2045 or, respectively, a thermoplastic resin such as e.g. a polycarbonate resin, a polyacrylic resin or a modified polyolefin resin. Examples of appropriate thermoplastic plastic material or thermoplastic resin may be taken, for example, from DE 699 23 847 T2. As a polycarbonate resin, DE 699 23 847 T2 consequently discloses the appropriate use of aromatic polycarbonate resin which has been obtained by processing a diphenol and a carbonate precursor. In this context, examples of the diphenol include bis-(hydroxylaryl)-alkanes such as 2,2-bis-(4-hydroxyphenyl)-propane (so-called bisphenol A), bis-(4-hydroxyphenyl)-methane, 1,1-bis-(4-hydroxyphenyl)-ethane, 2,2-bis-(4-hydroxyphenyl)-butane, 2,2-bis-(4-hydroxyphenyl)-octane, 2,2-bis-(4-hydroxyphenyl)-phenylmethane, 2,2-bis-(4-hydroxy-3-methylphenyl)-propane, 1,1-bis-(4-hydroxy-3-tert-butylphenyl)-propane, 2,2-bis-(4-hydroxy-3-bromophenyl)-propane, 2,2-bis-(4-hydroxy-3,5-dibromophenyl)-propane and 2,2-bis-(4-hydroxy-3,5-dichlorophenyl)-propane; bis-(hydroxyphenyl)-cycloalkane such as 1,1-bis-(hydroxyphenyl)-cyclopentane and 1,1-bis-(hydroxyphenyl)-cyclohexane; dihydroxyarylethers such as 4,4′-dihydroxydiphenylether and 4,4′-dihydroxy-3,3′-dimethyldiphenylether; dihydrodiarylsulfides such as 4,4′-dihydroxydiphenylsulfide and 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfide; Dihydroxydiarylsulfoxides such as 4,4′-dihydroxydiphenylsulfoxide and 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfoxide; and dihydroxydiarylsulfones such as 4,4′-dihydroxydiphenylsulfone and 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfone. These diphenols may be used per se or by way of a combination of two or more products. 
     The headlight lenses  200 .  300 ,  400 ,  500 A,  500 B, as well as the headlight lenses of the partial headlights  3001 .  3002 ,  3003 , and  3004  are configured in an analogue manner regarding headlight lens  100 , as has been represented, in a purely exemplary manner, in the example of headlight lens  300  of  FIG. 30 . Herein,  FIG. 30  shows the headlight lens  300  by way of a lateral cross-sectional view. The headlight lens  300  comprises a blank-molded monolithic body  3120  (=glass part) of inorganic glass. The blank-molded monolithic body  3120  comprises the light tunnel  308 , as well as a partial light passage section  3121 . The partial light passage section  3121  is partially injection molded-around by transparent plastic material for molding a further partial light passage section  3122 . The partial light passage section  3121  and the partial light passage section  3122  form the light passage section  309 . 
     The headlight lens  600  is—as has been represented in  FIG. 31 —also configured in an analogue manner. Herein,  FIG. 31  shows a cross section of the headlight lens  600  by way of a top view. The headlight lens  600  comprises a blank-molded monolithic body  6120 A (=glass part) made from inorganic glass, a blank-molded monolithic body  6120 B (=glass part) made from inorganic glass, and a blank-molded monolithic body  6120 C (=glass part) made from inorganic glass. The blank-molded monolithic body  6120 A comprises the light tunnel  608 A as well as a partial light passage section  6121 A. The partial light passage section  6121 A has been partially injection molded-around by transparent plastic material for forming a further partial light passage section  6122 . The blank-molded monolithic body  6120 B comprises the light tunnel  608 B as well as a partial light passage section  6121 B. The partial light passage section  6121 B has been partially injection molded-around by transparent plastic material for forming the partial light passage section  6122 . The blank-molded monolithic body  6120 C comprises the light tunnel  608 C as well as a partial light passage section  6121 C. The partial light passage section  6121 C has been partially injection molded-around by transparent plastic for forming a further partial light passage section  6122 . The partial light passage section  6121 A and the partial light passage section  6122  together form the light passage section  609 A. The partial light passage section  6121 B and the partial light passage section  6122 B together form the light passage section  609 B. The partial light passage section  6121 C and the partial light passage section  6122  together form the light passage section  609 C. 
     The headlight lens  600  may also be configured as has been represented in  FIG. 32 . Herein,  FIG. 32  shows a cross section of the headlight lens  600  by way of a top view. 
     The headlight lens  600  comprises a blank-molded monolithic body  6120 A′ (=glass part) from inorganic glass, a blank-molded monolithic body  6120 B′ (=glass part) from inorganic glass, and a blank-molded monolithic body  6120 C′ (=glass part) from inorganic glass. The blank-molded monolithic body  6120 A′ comprises the light tunnel  608 A as well as a partial light passage section  6121 A′. Transparent plastic material has been added-on by injection molding to the partial light passage section  6121 A′ for forming the partial light passage section  6122 ′. The blank-molded monolithic body  6120 B comprises the light tunnel  608 B as well as a partial light passage section  6121 B′. The partial light passage section  6121 B′ has been partially injection molded-around by transparent plastic material for forming the partial light passage section  6122 ′. The blank-molded monolithic body  6120 C comprises the light tunnel  608 C as well as a partial light passage section  6121   a . Transparent plastic has been added-on by injection-molding to the partial light passage section  6121 C′ for forming a the partial light passage section  6122 ′. The partial light passage section  6121 A′ and the partial light passage section  6122 ′ form the light passage section  609 A. The partial light passage section  6121 B′ and the partial light passage section  6122 ′ form the light passage section  609 B. The partial light passage section  6121   a  and the partial light passage section  6122 ′ form the light passage section  609 C. 
     The elements, distances and angles in the figures have been drawn in consideration of simplicity and clearness and not necessarily to scale. For example, the orders of magnitude of some elements, distances and angles have been exaggerated with respect to other elements, distances and angles in order to improve comprehension of the examples of embodiment of the present invention.