Patent Publication Number: US-7722234-B2

Title: Vehicle headlight

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to and incorporates by reference the entire contents of Japanese priority document 2006-318649 filed in Japan on Nov. 27, 2006. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a vehicle headlight. 
     2. Description of the Related Art 
     A conventional headlight for a vehicle currently in use radiates a light forward of a vehicle in a light distribution pattern including a cutoff line on a driving lane side that is on or near a horizontal line of a screen and a cutoff line on an oncoming lane side below the cutoff line on the driving lane side (hereinafter, simply “a light distribution pattern”). For example, a vehicle headlight disclosed in Japanese Patent Application Laid-open No. H11-232903 consists of a light source, a light shielding member, and a reflection surface that reflects a light emitted from a light emitter of the light source and reflects a light distribution pattern forward of a vehicle. When the light emitter emits light, a part of the light from the light emitter is shielded by the light shielding member, and a remaining part of the light from the light emitter, i.e., a part of the light that is not shielded by the light shielding member, is reflected by the reflection surface. Then, the light is radiated forward of the vehicle in the light distribution pattern. 
     However, because the vehicle headlight forms the cutoff line by the light shielding member, a light density is high near the cutoff line. Therefore, the vehicle headlight may cause a glare on the oncoming lane side, although the forward visibility is improved. 
     A vehicle headlight disclosed in Japanese Utility Model Application Laid-open No. H05-87704 is designed to reduce the light density near a cutoff line of a light distribution pattern. However, with the vehicle headlight disclosed in Japanese Utility Model Application Laid-open No. H05-87704, a problem arises in forward visibility on the driving lane side while an improvement can be obtained on the glare occurring on the oncoming lane side. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to at least partially solve the problems in the conventional technology. 
     A vehicle headlight according to one aspect of the present invention irradiates a road ahead of a vehicle with a light distribution pattern including a first cutoff line substantially on a horizontal line of a screen on a driving lane side and a second cutoff line on an oncoming lane side. The vehicle headlight includes a light source that radiates a light; a light shielding member that shields a part of the light radiated from the light source and passes a remaining part of the light; and a reflection surface that reflects the light that passes the light shielding member ahead of the vehicle as the light distribution pattern. The reflection surface includes a first reflection surface that forms a first light distribution pattern mainly including the first cutoff line on the driving lane side, and a second reflection surface that forms a second light distribution pattern mainly including the second cutoff line on the oncoming lane side. Each of the first reflection surface and the second reflection surface has a width in an up-and-down direction with respect to a horizontal line that passes the light source. A shape of the light shielding member is projected substantially to the horizontal line that passes the light source in the first reflection surface to form the first cutoff line on the driving lane side. The light shielding member includes a first edge that increases a light density around the first cutoff line on the driving lane side in the first light distribution pattern. 
     The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of a light source and reflection surfaces of a reflector of a vehicle headlight according to a first embodiment of the present invention; 
         FIG. 2  is a schematic diagram for explaining a light distribution pattern that is obtained by reflecting a light from the light source by the reflection surfaces of a paraboloid of revolution and radiating the light on a screen; 
         FIG. 3  is a schematic diagram for explaining the light distribution pattern and rectangular images of a filament of the light source; 
         FIG. 4  is a schematic diagram for explaining a state in which the light distribution pattern and the rectangular images are changed to a predetermined light distribution pattern by a first reflection surface and a second reflection surface; 
         FIG. 5  is a schematic diagram for explaining the predetermined light distribution pattern representing a first light distribution pattern to a third light distribution pattern in detail; 
         FIG. 6  is a schematic diagram of the predetermined light distribution pattern radiated on the screen; 
         FIG. 7  is a schematic diagram for explaining the third light distribution pattern in detail; 
         FIG. 8  is a schematic diagram for explaining a relation between the vehicle headlight and the screen; 
         FIG. 9  is a side view of a halogen lamp as the light source; 
         FIG. 10  is a cross section taken along line X-X in  FIG. 9 ; 
         FIG. 11  is a side view of a discharge lamp as the light source; 
         FIG. 12  is a schematic diagram of the discharge lamp seen from an arrow XII in  FIG. 11 ; 
         FIG. 13  is a front view of a light source and reflection surfaces of a reflector of a vehicle headlight according to a second embodiment of the present invention; 
         FIG. 14  is a cross section of a halogen lamp as the light source; and 
         FIG. 15  is a front view of a discharge lamp as the light source. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Exemplary embodiments of the present invention are explained in detail below with reference to the accompanying drawings. In the drawings, a symbol “F” indicates a forward direction of a vehicle (a forward-moving direction of the vehicle), a symbol “B” indicates a backward direction of the vehicle, a symbol “U” indicates an upward direction when seeing the forward direction from a driver side, a symbol “D” indicates a downward direction when seeing the forward direction from the driver side, a symbol “L” indicates a left direction when seeing the forward direction from a driver side, a symbol “R” indicates a right direction when seeing the forward direction from the driver side, a symbol “VU-VD” indicates a vertical line and an up-and-down vertical line on a screen S, a symbol “HL-HR” indicates a horizontal line and a right-to left horizontal line on the screen S, a symbol “Z-Z” indicates an optical axis of a reflection surface, a symbol “Z 1 -Z 1 ” indicates a lamp axis of a halogen lamp as a light source, and a symbol “Z 2 -Z 2 ” indicates a lamp axis of a discharge lamp as a light source. 
     A vehicle headlight  1  according to a first embodiment is explained referring to  FIGS. 1 to 12 . The vehicle headlight  1  is, for example, a vehicle headlamp, and is capable of forming a predetermined light distribution pattern (e.g., a light distribution pattern for a low-beam or a light distribution pattern for a high-beam). The vehicle headlight  1  is mounted on a vehicle that drives on the right side. 
     The vehicle headlight  1  is mounted on each of the right side (a right-side headlamp) and the left side (a left-side headlamp) on a front portion of the vehicle. 
     As shown in  FIG. 1 , the vehicle headlight  1  includes a light source  2 , a shade (light shielding member)  22 , and a reflector  3 . The reflector  3  includes a first reflection surface  31 , a second reflection surface  32 , a third reflection surface  33 , and a fourth reflection surface  34 . The light source  2 , the shade  22 , and the reflector  3  are arranged in a lamp chamber (not shown) divided by a lamp housing (not shown) and a lamp lens (not shown). 
     As shown in  FIGS. 9 and 10 , the light source  2  is an H4 halogen lamp or an HB2 halogen lamp in the present embodiment. The light source  2  includes a tube (a glass tube)  20 , a small cylindrical filament (a light emitter)  21  and the shade  22  arranged in the tube  20 , a base  23 , and a light shielding film (a black top)  24 . The light source  2  is a double-filament lamp; however, only one filament (a sub filament or a low beam filament) is shown in the drawings for the sake of explanation. 
     The shade  22  shields a part of the light emitted from the filament  21 , and allows a remaining part of the light to pass to the tube  20  side. The shade  22  has a dish-like shape with a circular cross section to cover the lower side of the filament  21 . The shade  22  includes a first edge  221  and a second edge  222 . As shown in  FIG. 10 , a center angle of the shade  22  (a center angle in a range from the first edge  221  to the second edge  222  or in a range in which a light from the filament  21  is shielded) is calculated by (180−θ)°. In the present embodiment, the angle θ is about 15°. As shown in  FIGS. 1 and 10 , the first edge  221  is positioned on the left side of the filament  21 , and the second edge  222  is positioned on the right side of the filament  21 . 
     The light source  2  is attached to the reflector  3  in a state in which the light source  2  is rotated in a direction indicated by an arrow (counterclockwise) in  FIG. 10  with respect to the attachment position of a light source in a conventional vehicle headlamp. Specifically, as shown in  FIGS. 1 and 10 , the light source  2  is attached to the reflector  3  in a state in which the light source  2  is rotated in the direction indicated by the arrow around the lamp axis Z 1 -Z 1  so that the first edge  221  is on or near a horizontal line HL-HR that passes the center of the filament  21 . Therefore, the first edge  221  is projected to or near the horizontal line HL-HR that passes the light source  2  in the leftmost side first reflection surface  31  as shown in a solid line in  FIG. 1 . 
     As shown in  FIGS. 1 and 10 , the second edge  222  is at a position rotated counterclockwise by the angle θ with respect to the horizontal line HL-HR. Therefore, the second edge  222  is projected to a position rotated counterclockwise by the angle θ with respect to the horizontal line HL-HR in the rightmost side second reflection surface  32  as shown in the solid line in  FIG. 1 . 
       FIGS. 2 and 3  are schematic diagrams for explaining a light distribution pattern P 10  radiated on a screen. The light distribution pattern P 10  is obtained by the following manner. That is, the light that is emitted from the filament  21  and passes the shade  22  (i.e., the light that is not shielded by the shade  22 ) is reflected by a reflection surface (not shown) of a paraboloid of revolution, and is radiated on the screen ahead, whereby the light distribution pattern P 10  is formed. The filament  21  is positioned forward of a focal point of the reflection surface of a paraboloid of revolution. Therefore, the light radiated from the filament  21  is reflected by the reflection surface of a paraboloid of revolution, intersects at a point that is forward of the focal point of the reflection surface of a paraboloid of revolution, and is then diffused to be radiated on the screen as the light distribution pattern P 10 . Thus, a shape of the light distribution pattern P 10  is a mirror image of the light image radiated from the filament  21  in a horizontal direction and a vertical direction. 
     Specifically, as shown in  FIG. 2 , the light distribution pattern P 10  has a fan-like shape and includes a horizontal first cutoff line CL 11  on a right driving lane  40  side and a diagonal second cutoff line CL 12  on a left oncoming lane  41  side. The horizontal first cutoff line CL 11  is formed by the first edge  221 , and the diagonal second cutoff line CL 12  is formed by the second edge  222 . In  FIGS. 2 ,  6 , and  7 , a center line  42 , a shoulder  43  on the right driving lane  40  side, and a shoulder  44  on the left oncoming lane  41  side are shown. 
     As shown in  FIG. 3 , rectangular images of the filament  21  are arranged in a radial direction in the light distribution pattern P 10 . The long sides of the rectangular images are along the horizontal first cutoff line CL 11  and the diagonal second cutoff line CL 12 . 
     As shown in  FIGS. 4 to 8 , the first to fourth reflection surfaces  31  to  34  reflect the light that is radiated from the filament  21  and passes the shade  22 , i.e., the light that is not shielded by the shade  22 , forward of the vehicle as a light distribution pattern P including a first cutoff line CL 1  on the right driving lane  40  side, a second cutoff line CL 2  on the left oncoming lane  41  side, and a slant third cutoff line CL 3  in the middle. The first cutoff line CL 1  is on or near the horizontal line HL-HR of the screen S. The second cutoff line CL 2  is below the first cutoff line CL 1 . The slant third cutoff line CL 3  is on or near the center line  42  between the first cutoff line CL 1  and the second cutoff line CL 2 . The light distribution pattern P including the cutoff lines CL 1  to CL 3  is, for example, a light distribution pattern for a low-beam and a light distribution pattern for a high-beam. 
     The first to fourth reflection surfaces  31  to  34  are formed by performing an aluminum deposition, a silver painting, or the like. As shown in  FIGS. 1 and 8 , each of the first to fourth reflection surfaces  31  to  34  is a reflection surface such as a free curved surface (a non-uniform rational B-spline (NURBS) curved surface) based on a parabola (a paraboloid of revolution). The NURBS curved surface of each of the first to fourth reflection surfaces  31  to  34  is a free curved surface of the NURBS described in “Mathematical Elements for Computer Graphics” (Devid F. Rogers, J Alan Adams). A through hole (not shown) for attaching the light source  2  is formed in the center of the reflector  3 . 
     The reflection surface of the reflector  3  includes the first to fourth reflection surfaces  31  to  34  as above. 
     As shown in  FIG. 1 , the first reflection surface  31  is positioned on the left side of the light source  2  in the reflector  3 , and has a width in an up-and-down direction with respect to the horizontal line HL-HR. As shown in  FIG. 1 , the first reflection surface  31  includes vertically divided five segments  311 ,  312 ,  313 ,  314 , and  315 . The first reflection surface  31  forms a first light distribution pattern P 1  mainly including the first cutoff line CL 1 . Specifically, the first reflection surface  31  raises the horizontal first cutoff line CL 11  shown in  FIG. 2  to the horizontal line HL-HR or to a position near the horizontal line HL-HR to form the first cutoff line CL 1 , and expands a light distribution pattern including the horizontal first cutoff line CL 11  in the light distribution pattern P 10  shown in  FIG. 2  largely in a horizontal direction and a little in a vertical direction to form the first light distribution pattern P 1  including the first cutoff line CL 1 . 
     More specifically, as shown in  FIG. 4 , the first reflection surface  31  raises the rectangular images of the filament  21  whose long sides are along the horizontal first cutoff line CL 11  shown in  FIG. 2  to the horizontal line HL-HR or to a position near the horizontal line HL-HR without changing the direction of the rectangular images, and expands an area of the rectangular images largely in the horizontal direction and a little in the vertical direction. Because the long sides of the rectangular images expanded in such manner are along the first cutoff line CL 1 , a light density (brightness, illuminance, light quantity) near the first cutoff line CL 1  is high. Consequently, with a simple design of the reflection surface, the first reflection surface  31  can form the first light distribution pattern P 1  having a high light density near the first cutoff line CL 1 . 
     Light distribution patterns P 11 , P 12 , P 13 , P 14 , and P 15  in the first light distribution pattern P 1  are mainly formed by the segments  311 ,  312 ,  313 ,  314 , and  315 , respectively. 
     As shown by the solid line in  FIG. 1 , the first edge  221  is projected to or near the horizontal line HL-HR in the first reflection surface  31 , so that the first cutoff line CL 1  is formed by the first edge  221 . As shown in  FIG. 5 , because the first edge  221  cuts off the first light distribution pattern P 1  at a portion having a high light density in the first light distribution pattern P 1 , the light density near the first cutoff line CL 1  becomes high in the first light distribution pattern P 1 . 
     As shown in  FIG. 1 , the second reflection surface  32  is positioned on the right side of the light source  2  in the reflector  3 , and has a width in the up-and-down direction with respect to the horizontal line HL-HR. The lower borderline of the second reflection surface  32  is on or near the line that is rotated counterclockwise by the angle θ around the light source  2  with respect to the horizontal line HL-HR. As shown in  FIG. 1 , the second reflection surface  32  includes vertically divided five segments  321 ,  322 ,  323 ,  324 , and  325 . The second reflection surface  32  forms a second light distribution pattern P 2  mainly including the second cutoff line CL 2 . Specifically, the second reflection surface  32  makes the diagonal second cutoff line CL 12  shown in  FIG. 2  horizontal and lowers the diagonal second cutoff line CL 12  below the first cutoff line CL 1  to form the second cutoff line CL 2 , and expands a light distribution pattern including the diagonal second cutoff line CL 12  in the light distribution pattern P 10  shown in  FIG. 2  largely in the horizontal direction and a little in the vertical direction to form the second light distribution pattern P 2  including the second cutoff line CL 2 . 
     More specifically, as shown in  FIG. 4 , the second reflection surface  32  lowers the obliquely arranged rectangular images of the filament  21  whose long sides are along the diagonal second cutoff line CL 12  shown in  FIG. 2  below the first cutoff line CL 1  without changing the direction of the rectangular images, and expands an area of the rectangular images largely in the horizontal direction and a little in the vertical direction. Because only the corners of the rectangular images are on the second cutoff line CL 2 , the light density near the second cutoff line CL 2  is low. Consequently, with a simple design of the reflection surface, the second reflection surface  32  can form the second light distribution pattern P 2  having a low light density near the second cutoff line CL 2 . 
     Light distribution patterns P 21 , P 22 , P 23 , P 24 , and P 25  in the second light distribution pattern P 2  are mainly formed by the segments  321 ,  322 ,  323 ,  324 , and  325 , respectively. 
     As shown by the solid line in  FIG. 1 , the second edge  222  is projected to or near the lower borderline of the second reflection surface  32  (a line that is rotated counterclockwise by the angle θ around the light source  2  with respect to the horizontal line HL-HR or in the vicinity of the line), so that the second cutoff line CL 2  is formed by the second edge  222 . As shown in  FIG. 5 , because the second edge  222  cuts off the second light distribution pattern P 2  at a portion having a low light density in the second light distribution pattern P 2 , the light density near the second cutoff line CL 2  becomes low in the second light distribution pattern P 2 . 
     As shown in  FIG. 1 , the third reflection surface  33  is positioned on the right side of the light source  2  and above the second reflection surface  32  in the reflector  3 , and has a width in the up-and-down direction with respect to a diagonal line S 3  that extends from the center of the light source  2 . In other words, the third reflection surface  33  is in an area that is obliquely upward from the horizontal line HL-HR in the second reflection surface  32 . The diagonal line S 3  is a line that extends from the center of the light source  2  to a direction rotated clockwise by an angle (a center angle) θ s  with respect to the horizontal line HL-HR in the second reflection surface  32 . As shown in  FIG. 7 , the angle θ s  coincides or substantially coincides with an angle made by a line extended from the second cutoff line CL 2  (see, a chain double-dashed line in  FIG. 7 ) and the slant third cutoff line CL 3 . 
     As shown in  FIG. 1 , the third reflection surface  33  includes vertically (longitudinally) divided three segments. The third reflection surface  33  mainly includes the slant third cutoff line CL 3 , and forms a third light distribution pattern between the first light distribution pattern P 1  and the second light distribution pattern P 2 . Specifically, the third reflection surface  33  reflects a part of the light distribution pattern P 10  shown in  FIG. 2  to form the slant third cutoff line CL 3  and a third light distribution pattern P 3  including the slant third cutoff line CL 3 . 
     Although the borderlines between the segments of each of the first to third reflection surfaces  31  to  33  are shown in  FIG. 1 , there may be no borderline or a borderline cannot be recognized depending upon the segments. 
     As shown in  FIG. 1 , the fourth reflection surface  34  is provided in an area above the first reflection surface  31  and the third reflection surface  33 . The fourth reflection surface  34  expands a part of the light distribution pattern P 10  largely in the horizontal direction and a little in the vertical direction to form a light distribution pattern that does not include the first to third light distribution patterns P 1  to P 3 , or a light distribution pattern that includes all of or a part of the first to third light distribution patterns P 1  to P 3 . 
     The operation by the vehicle headlight  1  is explained. First, when a current is applied to the filament  21 , a part of the light radiated from the filament  21  is shielded by the shade  22  (the shielding member). A remaining part of the light that is not shielded by the shade  22  is reflected by the first to fourth reflection surfaces  31  to  34 , and is radiated forward of a vehicle as the predetermined light distribution pattern P as shown in  FIG. 8 . 
     As shown in  FIGS. 5 to 8 , the predetermined light distribution pattern P includes the first cutoff line CL 1 , the second cutoff line CL 2 , and the slant third cutoff line CL 3 . Specifically, as show in  FIG. 8 , the predetermined light distribution pattern P includes the first light distribution pattern P 1  including the first cutoff line CL 1 , the second light distribution pattern P 2  including the second cutoff line CL 2 , the third light distribution pattern P 3  including the slant third cutoff line CL 3 , and other light distribution patterns. 
     The first light distribution pattern P 1  including the first cutoff line CL 1  is formed by the first reflection surface  31 , and the light density near the first cutoff line CL 1  is high. The second light distribution pattern P 2  including the second cutoff line CL 2  is formed by the second reflection surface  32 , and the light density near the second cutoff line CL 2  is low. The third light distribution pattern P 3  including the slant third cutoff line CL 3  is formed by the third reflection surface  33 . Other light distribution patterns are formed by the fourth reflection surface  34 . 
     According to the first embodiment, because the first edge  221  is projected to or near the horizontal line HL-HR, the first cutoff line CL 1  is formed by the first edge  221  and the light density near the first cutoff line CL 1  can be high in the first light distribution pattern P 1 . Thus, the vehicle headlight  1  can improve the visibility on the right driving lane  40  side. 
     Furthermore, according to the first embodiment, the light density near the second cutoff line CL 2  is low in the second light distribution pattern P 2 . Thus, the vehicle headlight  1  does not cause glare on the left oncoming lane  41  side and discomfort due to the sharp light-dark border. 
     Moreover, according to the first embodiment, the third reflection surface  33  that is provided in an area obliquely upward from the horizontal line HL-HR in the second reflection surface  32  forms the third light distribution pattern P 3  including the slant third cutoff line CL 3  on or near the center line  42  between the first light distribution pattern P 1  and the second light distribution pattern P 2 . An area A that is hatched with dotted lines in  FIG. 7 , i.e., the area A that includes the center line  42  and a portion near the center line  42 , can be irradiated with the third light distribution pattern P 3 . As shown in  FIG. 7 , the area A covers a distant area on the right driving lane  40  side, but covers little of an area on the left oncoming lane  41  side. Thus, the vehicle headlight  1  can further improve the visibility on the right driving lane  40  side, and does not cause glare on the left oncoming lane  41  side. The chain double-dashed line in  FIG. 7  represents an extension line of the second cutoff line CL 2  and a diagonal cutoff line that connects the first cutoff line CL 1  and the extension line of the second cutoff line CL 2  when the third light distribution pattern P 3  cannot be obtained by the third reflection surface  33 . 
     Furthermore, according to the first embodiment, the vehicle headlight  1  can be achieved simply by providing the first to fourth reflection surfaces  31  to  34 , and changing the attachment position of the light source, i.e., rotating the light source in the direction indicated by the arrow (counterclockwise) in  FIG. 10 , without necessitating any new component. Thus, the manufacturing cost can be reduced. 
       FIGS. 11 and 12  are schematic diagrams for explaining an example in which a discharge lamp is used as a light source  200  instead of the halogen lamp. 
     The light source  200  is, for example, a gas-discharge light source. In the example, a high-pressure metal discharge lamp or a high-intensity discharge lamp (HID) such as a metal halide lamp is used as the light source  200 . The light source  200  includes an outer tube (a glass tube)  201 , a luminous tube (a light emitter)  202  arranged in the outer tube  201 , light shielding films (shade stripes, black stripes)  203  and  204  as light shielding members arranged in the outer tube  201 , and a base  205 . In  FIG. 12 , a shade  206  is shown. 
     A noble gas (a xenon gas), a mercury, a metal iodide (sodium, scandium), or the like is filled in the luminous tube  202 . An electrode on the base  205  side and an electrode on the side of a lead wire provided to the tip in the outer tube  201  through a ceramic pipe oppose each other with a slight clearance therebetween. When a voltage is applied between the electrodes, an arc discharge occurs in the luminous tube  202 , so that the luminous tube  202  emits light. As shown in  FIG. 12 , the light shielding films  203  and  204  each having a predetermined width (a predetermined center angle) are provided to the outer tube  201 . An angle between an upper first edge  207  of the light shielding film  203  on the left side (a border line on the clockwise side) and an upper second edge  208  of the light shielding film  204  on the right side (a border line on the counterclockwise side) is in a range of (180+θ)°. The light source  200  is a D2R lamp or a D4R lamp provided with two light shielding stripes as a light shield coating in this example. 
     The light source  200  is attached to the reflector  3  in the same manner as the light source  2 . That is, as shown in  FIG. 12 , the light source  200  is attached to the reflector  3  in a state in which the light source  200  is rotated in a direction indicated by an arrow (counterclockwise) around a lamp axis Z 2 -Z 2  so that the upper first edge  207  is on or near a horizontal line HL-HR that passes the center of the luminous tube  202 . Therefore, the upper first edge  207  is projected to or near the horizontal line HL-HR in the leftmost side first reflection surface  31  (see  FIG. 1 ). 
     As shown in  FIG. 12 , the upper second edge  208  is at a position rotated counterclockwise by the angle θ with respect to the horizontal line HL-HR. Therefore, the upper second edge  208  is projected to a position rotated counterclockwise by the angle θ with respect to the horizontal line HL-HR in the rightmost side second reflection surface  32  (see  FIG. 1 ). 
     The light source  200  is configured in such a manner, so that the light source  200  can obtain the same operational effects as the light source  2  that is a halogen lamp. That is, the vehicle headlight  1  can be achieved simply by providing the first to fourth reflection surfaces  31  to  34  and changing the attachment position of the light source without necessitating any new component. Thus, the manufacturing cost can be reduced. 
       FIGS. 13 to 15  are schematic diagrams of a vehicle headlight  100  according to a second embodiment of the present invention. In  FIGS. 13 to 15 , the components same as those in  FIGS. 1 to 12  are given the same reference numerals. The vehicle headlight  100  is mounted on a vehicle that drives on the left side. 
     The vehicle headlight  100  includes a reflector  300  that has the first reflection surface  31 , the second reflection surface  32 , the third reflection surface  33 , and the fourth reflection surface  34 . The first to fourth reflection surfaces  31  to  34  are arranged in a mirror-inverted manner with respect to those of the vehicle headlight  1  in the first embodiment. 
     As shown in  FIG. 14  ( FIG. 15 ), the light source  2  (the light source  200 ) is attached to the reflector  300  in a state in which the light source  2  (the light source  200 ) is rotated in a direction indicated by an arrow (counterclockwise) around a lamp axis Z 1 -Z 1  (a lamp axis Z 2 -Z 2 ) so that the second edge  222  of the shade  22  (the upper second edge  208  of a second light shielding film  204 ) is on or near a horizontal line HL-HR that passes the center of the filament  21  (the luminous tube  202 ). Therefore, the second edge  222  (the upper second edge  208 ) is projected to or near the horizontal line HL-HR that passes the center of the light source  2  (the light source  200 ) in the rightmost side first reflection surface  31  (see  FIG. 13 ). That is, the second edge  222  (the upper second edge  208 ) in the second embodiment works as the first edge  221  (the upper first edge  207 ) in the first embodiment. 
     As shown in  FIG. 14  ( FIG. 15 ), the first edge  221  of the shade  22  (the upper first edge  207  of a first light shielding film  203 ) is at a position rotated counterclockwise by an angle θ with respect to the horizontal line HL-HR that passes the filament  21  (the luminous tube  202 ). Therefore, the first edge  221  (the upper first edge  207 ) is projected to a position rotated counterclockwise by the angle θ with respect to the horizontal line HL-HR that passes the center of the light source  2  (the light source  200 ) in the leftmost side second reflection surface  32  (see  FIG. 13 ). That is, the first edge  221  (the upper first edge  207 ) in the second embodiment works as the second edge  222  (the upper second edge  208 ) in the first embodiment. 
     The vehicle headlight  100  according to the second embodiment is configured in such a manner that the vehicle headlight  100  can obtain the same operational effects as the headlight  1  according to the first embodiment. 
     Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.