FIELD
The present disclosure relates to an improved dual beam headlamp assembly.
BACKGROUND
Headlamps or headlights are often used in automobiles, and other motorized vehicles, to control and focus light in a desired direction. The light may be produced by an incandescent bulb, a halogen bulb, a light emitting diode (LED) or other light source and transmitted to and from a series of reflectors and/or lens, prior to being delivered to the path of the vehicle. Some headlamps suffer from low optical efficiency, high cost, or poor beam pattern distribution. In order to improve the performance and efficiency of a headlamp assembly, it may be desirable to maximize the amount of light that is directed in the desired direction, and minimize the amount of light that is lost to the surroundings.
This section provides background information related to the present disclosure which is not necessarily prior art.
SUMMARY
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
A headlamp assembly for projecting light in a forward direction along an optical axis is provided. The headlamp assembly include: a housing, a low beam light emitting device, a high beam light emitting device, a low beam lens, a high beam lens, and a reflector. The low beam and high beam light emitting devices may be arranged in the housing and include first and second planar surfaces, respectively, from which light is emitted. The normal to the first and second planar surfaces may be oriented away from the optical axis at substantially forty-five degrees in relation to the optical axis. The normal to the second planar surface may be oriented away from the normal to the first planar surface at substantially ninety degrees. The low beam and high beam lens may be arranged in the housing to receive a portion of the light emitted from the low beam and high beam light emitting devices, respectively, and operable to direct the light in the forward direction along the optical axis. The reflector may be arranged in the housing to receive a remaining portion of the light emitted from the low beam and high beam light emitting devices and reflect the remaining portion of the light in the forward direction along the optical axis.
The low beam lens can include a first planar lens surface and the high beam lens can include a second planar lens surface, such that the first planar lens surface is oriented from the first planar surface of the low beam light source at substantially forty-five degrees and the second planar lens surface is oriented from the second planar surface of the high beam light source at substantially forty-five degrees.
The headlamp assembly may further include a leg, wherein the low beam lens is mounted to a first side of the leg and the high beam lens is mounted to a second side of the leg, opposite the first side.
The headlamp assembly further includes a bracket having a first mount surface and a second mount surface, wherein an angle between the first mount surface and the second mount surface is substantially equal to ninety degrees, and the low beam light emitting device is disposed on the first mount surface and the low beam light emitting device is disposed on the second mount surface.
The reflector can include a low beam portion and a high beam portion, wherein the low beam portion is positioned above the low beam lens and the low beam light emitting device in relation to the optical axis and has a reflecting surface with a shape obtained by revolving a parabola ninety degrees around its axis, and the high beam portion is positioned below the high beam lens and the high beam light emitting device in relation to the optical axis and has a reflecting surface with a shape obtained by revolving a parabola ninety degrees around its axis. The reflecting surface of the low beam portion and the high beam portion of the reflector can be comprised of a plurality of reflecting surfaces, where each reflecting surface has a parabolic shape.
The low beam portion and the high beam portion of the reflector define an aperture therebetween, wherein the low beam light emitting device and the high beam light emitting device are disposed substantially within the aperture.
According to another particular aspect, a headlamp assembly for projecting light in a forward direction along an optical axis is provided. The headlamp assembly include: a housing, a low beam light emitting device, a low beam lens, a high beam light emitting device, a high beam lens, a reflector, and a bracket. The housing defines an aperture therein. The low beam light emitting device is arranged in the housing and has a planar surface from which light is emitted. The low beam lens is arranged in the housing to receive a portion of the light emitted from the low beam light emitting device and is operable to direct the light in the forward direction along the optical axis. The high beam light emitting device is arranged in the housing and has a planar surface from which light is emitted. The high beam lens is arranged in the housing to receive a portion of the light emitted from the high beam light emitting device and is operable to direct the light in the forward direction along the optical axis. The reflector is arranged in the housing to receive a remaining portion of the light emitted from the low beam light emitting device and the high beam light emitting device. The reflector is also arranged to reflect the remaining portion of the light in the forward direction along the optical axis. The normal to the planar surface of the low beam light emitting device is orientated in relation to the normal of the planar surface of the high beam light emitting device in a manner that creates a space within the housing in which light from the low beam light emitting device and from the high beam light emitting device does not pass through. The bracket is disposed in the space within the housing in which light from the low beam light emitting device and from the high beam light emitting device does not pass through. The low beam lens and the high beam lens are attached to the bracket. The low beam light emitting device and the high beam light emitting device can also be disposed substantially in the space
The low beam lens may be formed in shape of a cylinder cut in half along a longitudinal axis thereof to define a flat surface opposing a curved surface, such that the flat surface is arranged to receive the portion of the light emitted from the low beam light emitting device; whereas, the high beam lens may be formed in shape of a cylinder cut in half along a longitudinal axis thereof to define a flat surface opposing a curved surface, such that the flat surface is arranged to receive the portion of the light emitted from the high beam light emitting device. The flat surface of the low beam lens is preferably oriented at substantially forty-five degrees in relation to the planar surface of the low beam light emitting device, and the flat surface of the high beam lens is preferably oriented at substantially forty-five degrees in relation to the planar surface of the high beam light emitting device.
The reflector includes a low beam portion and a high beam portion. The low beam portion is positioned above the low beam lens and the low beam light emitting device in relation to the optical axis and has a reflecting surface with a shape obtained by revolving a parabola ninety degrees around its axis. Likewise, the high beam portion is positioned below the high beam lens and the high beam light emitting device in relation to the optical axis and has a reflecting surface with a shape obtained by revolving a parabola ninety degrees around its axis.
The low beam portion of the reflector can include a plurality of reflecting surfaces, such that each reflecting surface has a different focal point on the planar surface of the low beam light emitting device and the high beam portion of the reflector has a plurality of reflecting surfaces, such that each reflecting surface has a different focal point on the planar surface of the high beam light emitting device. In some embodiments, the reflector can be configured such that light is only reflected once off a surface thereof.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
FIG. 1 is a perspective view of a dual beam headlamp assembly, in accordance with the principles of the present disclosure;
FIG. 2a is a cross-sectional side view of the dual beam headlamp assembly of FIG. 1 taken along the line 2a-2a, showing the ray traces produced by a series of reflectors;
FIG. 2b is a cross-sectional side view of the dual beam headlamp assembly of FIG. 1 taken along the line 2a-2a, showing the ray traces produced by a first lens and a second lens;
FIG. 3a is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 3a-3a, with the first lens and the second lens removed;
FIG. 3b is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 3b-3b, showing the first lens;
FIG. 3c is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 3b-3b, showing the first lens and the ray traces produced by the series of reflectors;
FIG. 3d is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 3b-3b, showing the first lens and the ray traces produced by segments of the first lens;
FIG. 3e is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 3b-3b, showing the first lens and the ray traces produced by a segment of the first lens;
FIG. 4a is a cross-sectional bottom view of the dual beam headlamp assembly of FIG. 1 taken along the line 4a-4a, with the first lens and the second lens removed;
FIG. 4b is a cross-sectional bottom view of the dual beam headlamp assembly of FIG. 1 taken along the line 4b-4b, showing the second lens;
FIG. 4c is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 4b-4b, showing the second lens and the ray traces produced by the series of reflectors;
FIG. 4d is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 4b-4b, showing the second lens and the ray traces produced by segments of the second lens;
FIG. 4e is a cross-sectional top view of the dual beam headlamp assembly of FIG. 1 taken along the line 4b-4b, showing the second lens and the ray traces produced by a segment of the second lens;
FIG. 5 is a front view of a portion of the series of reflectors of the dual beam headlamp assembly of FIG. 1;
FIG. 6 is a schematic representation of the light produced by the dual beam headlamp assembly of FIG. 1;
FIG. 7 is an illustration of the intensity of a vertical section of the light pattern produced by the dual beam headlamp assembly of FIG. 1;
FIG. 8a is an illustration of the light pattern produced by the first lens of the dual beam headlamp assembly of FIG. 1;
FIG. 8b is an illustration of the light pattern produced by a first series of reflectors of the dual beam headlamp assembly of FIG. 1;
FIG. 8c is an illustration of the light pattern produced by the first lens and the first series of reflectors of FIGS. 8a and 8b;
FIG. 9a is an illustration of the light pattern produced by the second lens of the dual beam headlamp assembly of FIG. 1;
FIG. 9b is an illustration of the light pattern produced by a second series of reflectors of the dual beam headlamp assembly of FIG. 1;
FIG. 9c is an illustration of the light pattern produced by the second lens and the second series of reflectors of FIGS. 9a and 9b; and
FIG. 10 is an illustration of the light pattern produced by the first and second lens and first and second series of reflectors of FIGS. 8c and 9c.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
Example embodiments will now be described more fully with reference to the accompanying drawings.
With reference to the figures, a headlamp assembly 10 is provided and may include a reflector subassembly 12 and an illuminator subassembly 14. The headlamp assembly 10 may be used to project light in a forward direction along an optical axis 11 (FIG. 2a). The reflector subassembly 12 may include a first portion 16a and a second portion 16b. It will be appreciated that, while the reflector subassembly 12 is described as including separate first and second portions 16a, 16b, the first and second portions 16a, 16b may be integrally formed as part of a unitary reflector subassembly 12. The first and second portions 16a, 16b may include substantially arcuate shell portions 20a, 20b, respectively, having an arcuate rim portion 18a, 18b at a distal end thereof. The rim portions 18a, 18b may extend from a first end 22a, 22b to a second end 24a, 24b, respectively, and may be integrally formed with the shell portions 20a, 20b.
Each shell portion 20a, 20b may include a recessed portion 25a, 25b, respectively, at a proximal end thereof, opposite the rim portion 18a, 18b. The first and second portions 16a, 16b may be arranged in a variety of configurations to control the direction of light emitted from the headlamp assembly 10. With particular reference to FIG. 1, in the example embodiment, the first end 22a of the rim portion 18a may extend from the first end 22b of the rim portion 18b, and the second end 24a of the rim portion 18a may extend from the second end 22b of the rim portion 18b, such that the rim portions 18a, 18b may substantially form the shape of a confocal parabolic cylinder, resembling the shape of an “8,” and the recessed portions 25a, 25b may cooperate to form an aperture 26 in the reflector subassembly 12. In an alternative embodiment, the first and second portions 16a, 16b may be arranged in a side-by-side configuration, such that the first end 22a of the rim portion 18a is adjacent to the first end 22b of the rim portion 18b, and the first and second portions 16a, 16b substantially form the shape of a “W.” In another alternative embodiment, the arcuate portion of rim portion 18a may be adjacent to the arcuate portion of rim portion 18b, such that the first and second portions 16a, 16b substantially form the shape of an “X.”
Each of the arcuate shell portions 20a, 20b may generally be in the shape of a paraboloid. With reference to at least FIGS. 1 and 5, in the example embodiment, each of the shell portions 20a, 20b may take the shape of a semi-parabaloid. An inner surface 28a, 28b of the shell portions 20a, 20b may be generated by revolving a parabola around an axis 21a, 21b, respectively (FIGS. 3a, 4a), that is substantially parallel to the optical axis 11. Accordingly, the inner surface 28a, 28b of the shell portions 20a, 20b may be concave. With reference to at least FIG. 5, the inner surface 28a, 28b may include a series or array of variously-sized and shaped reflective elements 30a, 30b. The reflective elements 30a, 30b may be disposed at a variety of angles with respect to each other, such that light reflects from the reflective elements 30a, 30b in a variety of directions.
With reference to at least FIG. 2a, the illuminator subassembly 14 may include a mount or bracket 32, first and second light emitting devices or sources 34a, 34b, a brace or leg 36, and first and second lens 38a, 38b. As will be described in more detail below, the first light source 34a, the first lens 38a, and the first portion 16a of the reflector subassembly 12 may cooperate to form a low beam subsystem 39a (FIGS. 3a-3e) producing a low beam light pattern (FIGS. 8a, 8b, 8c). The second light source 34b, the second lens 38b, and the second portion 16b of the reflector subassembly 12 may cooperate to form a high beam subsystem 39b (FIGS. 4a-4e) producing a high beam light pattern (FIGS. 9a, 9b, 9c). In the example embodiment, and with respect to the frame of reference in FIG. 1, the low beam subsystem 39a may be located below the high beam subsystem 39b. In other embodiments, the low beam subsystem 39a may be located above the high beam subsystem 39b.
The bracket 32 may be mounted within the aperture 26 of the reflector subassembly 12 and may include a first mount surface 40a and second mount surface 40b. With reference to FIGS. 2a and 2b, in the example embodiment, the first and second mount surfaces 40a, 40b may substantially define a “V” shape, with the first mount surface 40a offset from the second mount surface 40b in a first direction X and angularly offset from the second mount surface by ninety (90) degrees. Similarly, the first and second mount surfaces 40a, 40b may each be offset from a horizontal plane by approximately forty-five (45) degrees. In other embodiments, the first mount surface 40a may be offset from the second mount surface 40b by ninety (90) degrees. The bracket 32 may also include other heat transferring features (e.g., fins) to transfer heat produced by the first and second light sources 34a, 34b out of the headlamp assembly 10.
With reference to FIGS. 2a and 2b, in the example embodiment of the headlamp assembly 10, the first and second light sources 34a, 34b may be light emitting diodes. In other embodiments, the first and second light sources 34a, 34b may be other flat, Lambertion light emitting devices. The first and second light sources 34a, 34b may be mounted to the bracket 32 and include a first light emitting surface 35 and a second light emitting surface 37, respectively. With particular reference to FIG. 2a, in the example embodiment, the normal 35a, 37a to the first and second light emitting surfaces 35, 37 is disposed at an angle α substantially equal to forty-five (45) degrees relative to the optical axis 11. It will be appreciated that the first and second light emitting surfaces 35, 37 may also be disposed at an angle substantially equal to one hundred thirty-five (135) degrees relative to the optical axis 11. In one configuration, the first light source 34a is fixed to the first mount surface 40a and the second light source 34b is fixed to the second mount surface 40b, such that the first light emitting surface 35 is offset from the second light emitting surface 37 (and the normal 35a to the first light emitting surface 35 is offset from the normal 37a to the second light emitting surface 37) by an angle β substantially equal to ninety (90) degrees. Additionally, the normal 35a, 37a to the first and second light emitting surfaces 35, 37, respectively, is angularly offset from a horizontal plane by approximately forty-five (45) degrees.
The angular configuration of the first and second light emitting surfaces 35, 37, described above creates a dead zone, or a space in which no light is transmitted, opposite the first and second light emitting surfaces 35, 37, and substantially aligned with an apex 55 of the reflector subassembly 12 (FIG. 2b). The aperture 26, bracket 32 and leg 36 are located in this zone, or space, in which no light is transmitted. Accordingly, one hundred percent (100%) of the light emitted from the first and second light emitting surfaces 35, 37 is transmitted from the headlamp assembly 10 in a direction opposite the apex 55, and none of the light emitted from the first and second light emitting surfaces 35, 37 is blocked by, or otherwise transmitted into, the aperture 26, bracket 32 or leg 36.
With reference to FIG. 2a, the first light source 34a may be offset from the second light source 34b in the first direction X and a second direction Y (perpendicular to the first direction X). Angling and positioning the first and second light sources 34a, 34b in the manner described herein allows for close placement and proximity of the first and second lens 38a, 38b relative to the first and second light sources 34a, 34b, respectively. The close proximity of the first and second lens 38a, 38b relative to the first and second light sources 34a, 34b, ensures that the light reflected from the first and second portions 16a, 16b of the reflector subassembly 12 does not hit, or otherwise refract through, the first and second lens 38a, 38b prior to being transmitted from the headlamp assembly 10. The close proximity of the first and second lens 38a, 38b relative to the first and second light sources 34a, 34b, respectively, also allows the first and second lens to intercept and control one hundred percent (100%) of the light that is not reflected from the first and second portions 16a, 16b of the reflector subassembly 12.
Angling and positioning the first and second light sources 34a, 34b in the manner described herein also ensures that the spaces behind the first and second light sources 34a, 34b and between the first and second lens 38a, 38b, in which light is not emitted, are substantially aligned with the apex 55 of the reflector subassembly 12. As described above, the bracket 32, the leg 36, and other thermal management features (not shown) and lens support structures are located in this zone, or space, in order to ensure that they will not impact optical performance by blocking any of the light transmitted from the first and second light sources 34a, 34b. During operation of the headlamp assembly 10, described in more detail below, the arrangement described above creates a desirable mix of optical images.
The first and second lens 38a, 38b may be mounted within the headlamp assembly 10 using the leg 36. The leg 36 may include a first end 42 and a second end 44. The first end 42 may be mounted to the bracket 32. The second end 44 may be offset from the first end 42 in a direction substantially perpendicular to a horizontal plane and the optical axis 11.
The first lens 38a may be substantially shaped as an oblong and truncated hemisphere having an arcuate surface 51 and a substantially planar surface 53 opposite the arcuate surface. The planar surface 53 may face the first light source 34a. In the example embodiment, the first lens 38a may be formed from plastic. In other embodiments, the first lens 38a may be formed from a crystal, a glass, or another suitable composite. With reference to at least FIGS. 3b-3e, the first lens 38a may include a first segment 46, a second segment 48, and a third segment 50. The first segment 46 may be substantially identical to the third segment 50. Accordingly, like numerals will be used to identify like features on the first and third segments 46, 50. The first and third segments 46, 50 may each form a truncated spherical quadrant of the first lens 38a, and the second segment 48 may form a semi-cylindrical segment of the first lens 38a. The second segment 48 may be formed by extrusion and may be located between the first segment 46 and the third segment 50. The first and third segments 46, 50 may each include a truncated end 52 defining first and second planar surfaces 49a, 49b (FIG. 1), respectively. With reference to at least FIG. 3b, the truncated end 52 prevents the first lens 38a from blocking the light from the first light source 34a, such that the light from the first light source 34a reaches the rim portion 18a of the reflector subassembly 12.
With reference to at least FIG. 3d, the first lens 38a may be arranged in the first portion 16a of the reflector subassembly 12 to receive a first portion of the light emitted from the first light source 34a. The first lens 38a may operate to direct the first portion of light in the forward direction along the optical axis 11. In the example embodiment, the first lens 38a may be mounted between the first end 42 and the second end 44 of the leg 36. The planar surface 53 of the lens 38a may be angularly offset from the normal 35a to the first light emitting surface 35 by an angle δ1 substantially equal to forty-five (45) degrees (FIG. 2b). The planar surface 53 may also form a ninety (90) degree angle with a horizontal plane and the optical axis 11.
With reference to FIGS. 4b-4e, the second lens 38b may include a first segment 54, a second segment 56, and a third segment 58. In the example embodiment, the second lens 38b may be formed from plastic. In other embodiments, the second lens 38b may be formed from a crystal, a glass, or another suitable composite. The first segment 54 may be substantially identical to the third segment 58. Accordingly, like numerals will be used to identify like features on the first and third segments 54, 58. The first and third segments 54, 58 may each be shaped as a quadrant of a sphere, such that the second lens 38b is substantially shaped as an oblong hemisphere having an arcuate surface and a substantially planar surface 62 opposite the arcuate surface. The planar surface 62 may face the second light source 34b. With particular reference to at least FIG. 4b, the second lens 38b may be located within the arcuate shell portion 20b of the reflector subassembly 12 such that the second lens 38b does not block or prevent the light from the second light source 34b from reaching the rim portion 18b of the reflector subassembly 12. The second segment 48 may be located between the first segment 54 and the third segment 58. The second segment 56 may be shaped as a semi-cylinder. The radius of the semi-cylindrical second segment 56 may be greater than the radius of the spherical quadrants formed by the first and third segments 54, 58, such that the an arcuate surface 60a of the second segment extends beyond, and is offset from, an arcuate surface 60b of the first and third segments 54, 58. The second segment 56 may be formed by extrusion.
The second lens 38b may be arranged in the second portion 16b of the reflector subassembly 12 to receive a first portion of the light emitted from the second light source 34b. The second lens 38b may operate to direct the first portion of light in the forward direction along the optical axis 11. In the example embodiment, the second lens 38b may be mounted to the second end 44 of the leg 36, such that the first lens 38a is located between the second lens 38b and the first end 42 of the leg 36, and offset from the first lens 38a in the first direction X and the second direction Y. The planar surface 62 of the second lens 38b may be angularly offset from the normal 37a to the second light emitting surface 37 by an angle δ1 substantially equal to forty-five (45) degrees (FIG. 2b). The planar surface 62 may also form a ninety (90) degree angle with a horizontal plane and the optical axis 11, and may be substantially parallel to the planar surface 53 of the first lens 38a.
When the first and second light sources 34a, 34b are illuminated, the profile of the first planar surface 53 of the first lens 38a and the profile of the second planar surface 62 of the second lens 38b may project back along the optical axis 11 in the direction of the first and second light sources, respectively. The size of the first and second lens 38a, 38b, and their proximity to the first and second light sources 34a, 34b, respectively, ensures that the aforementioned projected profile of the first and second lens 38a, 38b is substantially equal to the size of the aperture 26 and the size of the dead zone, or space, opposite the first and second light emitting surfaces 35, 37. Utilizing the correct optical prescription for the reflective elements 30a, 30b, and ensuring that the size of the projected profile of the first and second lens 38a, 38b is substantially equal to the size of the dead zone, ensures that the light from the reflector subassembly 12 does not interact or interfere with the optics on the first and second lens, while also ensuring that the first and second lens 38a, 38b and the reflector subassembly 12 only receive light directly from the first and second light sources 34a, 34b.
Operation of the headlamp assembly 10 will now be described in more detail. In the example embodiment, the first light source 34a cooperates with the first lens 38a and the first portion 16a of the reflector subassembly 12 to produce a low beam light pattern (FIGS. 8a, 8b, 8c), and the second light source 34b cooperates with the second lens 38b and the second portion 16b of the reflector subassembly 12 to produce a high beam light pattern (FIGS. 9a, 9b, 9c). When the first light source 34a is illuminated, a portion of the light may hit, and reflect from, the reflective elements 30a disposed on the first portion 16a of the reflector subassembly 12 (FIG. 2a, 3c). This portion of the light may produce a light pattern illustrated in FIG. 8b. Specifically, light reflecting from the reflective elements 30a positioned near the first light source 34a and/or the aperture 26 of the reflector subassembly 12 may produce tall images due to the relative proximity of the first light source 34a to the aperture 26. In addition, light reflecting from the reflective elements 30a positioned near the first light source 34a may produce a wide spread pattern due to the shape of the first portion 16a of the reflector subassembly 12, as described above. These tall images and the wide spread pattern can be seen at the left and right sides of the pattern illustrated in FIG. 8b (approximate x and y coordinates −40, −5 and 40, 5). Light reflecting from the reflective elements 30a positioned near the rim portion 18a of the reflector subassembly 12 may produce short images (i.e., a light pattern having a narrow spread and being tightly focused or concentrated), due to the relative distance of the first light source 34a from the rim portion 18a. These short images can be seen at the upper and central portions of the pattern illustrated in FIG. 8b (approximate x and y coordinates −10, 0 through 10, 0).
The remainder of the light produced by the first light source 34a may hit and refract through the first lens 38a (FIG. 2b). The remainder of the light may produce a light pattern illustrated in FIG. 8a. With reference to FIGS. 2a and 2b, due to the angular offset of the first light source 34a relative to the first lens 38a, described above, light transmitted or refracted through an upper portion or edge 64 (with respect to the frame of reference in FIG. 1) of the first lens 38a from the first light source 34a may produce tall images, while light transmitted through a lower portion or edge 66 of the first lens 38a from the first light source 34a may produce short images. The tall images can be seen near the lower portion of the pattern illustrated in FIG. 8a (approximate x and y coordinates −10, −10 through 10, −10). The short images can be seen near the upper portion of the pattern illustrated in FIG. 8a (approximate x and y coordinates −10, 0 through 10, 0). In addition, the light pattern transmitted by the second segment 48 of the first lens 38a may be characterized by a wide spread with a flat beam cutoff (FIG. 3e), while the light pattern transmitted by the first segment 46 and the third segment 50 of the first lens may be characterized by a more concentrated and tightly focused pattern (FIG. 3d). Prior to projecting from the headlamp assembly 10, one hundred percent (100%) of the light produced by the first light source 34a may contact the first lens 38a or the first portion 16a of the reflector subassembly 12, without contacting any additional portions or parts of the headlamp assembly 10.
When the second light source 34b is illuminated, a portion of the light may hit, and reflect from, the reflective elements 30b disposed on the second portion 16b of the reflector subassembly 12 (FIG. 2a). The portion of light may produce a light pattern illustrated in FIG. 9b. Specifically, light reflecting from the reflective elements 30b positioned near the second light source 34b and/or the aperture 26 of the reflector subassembly 12 may produce tall images due to the relative proximity of the second light source 34b to the aperture 26. In addition, light reflecting from the reflective elements 30b positioned near the second light source 34b may produce a wide spread pattern due to the shape of the second portion 16b of the reflector subassembly 12, as described above. These tall images and the wide spread pattern can be seen near the left and right sides, as well as the upper central portion, of the pattern illustrated in FIG. 9b (approximate x and y coordinates −10, 0 through 10, 0). Light reflecting from the reflective elements 30b positioned near the rim portion 18b of the reflector subassembly 12 may produce short images (i.e., a more tightly focused and narrower spread light pattern), due to the relative distance of the second light source 34b from the rim portion 18b. These short images can be seen near the lower central portion of the pattern illustrated in FIG. 9b (approximate x and y coordinates 0, 0).
The remainder of the light produced by the second light source 34b may hit and refract through the second lens 38b (FIG. 2b). The remainder of the light may produce a light pattern illustrated in FIG. 9a. With reference to FIGS. 2a and 2b, due to the angular offset of the second light source 34b relative to the second lens 38b, described above, light transmitted or refracted through a lower portion or edge 68 (with respect to the frame of reference in FIG. 1) of the second lens 38b from the second light source 34b may produce tall images, while light transmitted through an upper portion or edge 70 of the second lens 38b from the second light source 34b may produce short images. The tall images can be seen near the left and right sides of the pattern illustrated in FIG. 9a (approximate x and y coordinates −25, −0 through −10, −00). The short images can be seen near the upper central and lower central portions of the pattern illustrated in FIG. 9a (approximate x and y coordinates −0, −2 through 0, 2). In addition, the light pattern transmitted by the second segment 56 of the second lens 38b may be characterized by a wide spread with a flat beam cutoff (FIG. 4e), while the light pattern transmitted by the first segment 54 and the third segment 58 of the second lens may be characterized by a more concentrated and tightly focused pattern (FIG. 4d). Prior to projecting from the headlamp assembly 10, one hundred percent (100%) of the light produced by the second light source 34b may contact the second lens 38b or the second portion 16b of the reflector subassembly 12, without contacting any additional portions or parts of the headlamp assembly 10.
By arranging the first and second light sources 34a, 34b, the first and second lens 38a, 38b, and the first and second portions 16a, 16b of the reflector subassembly 12 in the manner described above, the headlamp assembly 10 is able to produce the light pattern illustrated in FIG. 10, whereby the light produced by the first and second light sources 34a, 34b makes only a single contact with the reflective elements 30a, 30b, respectively, or the lens 38a, 38b, respectively, thus improving the efficiency of the headlamp assembly 10. The combined light pattern (FIG. 7 and FIG. 10) may be characterized by a wide and medium spread pattern from the reflective elements 30a, 30b located near the aperture 26 (producing the tall and vertical images described above), and a tightly focused pattern from the reflective elements 30a, 30b located near the rim portions 18a, 18b (producing the shorter and horizontal images described above). The combined light pattern may have a compact, nearly circular forward profile whereby the light pattern has equal angles of output, such that the headlamp assembly 10 creates a uniform lighting pattern on the road surface (FIG. 6). Specifically, low intensity light (characterized by the tall images described above) may be focused closer to the headlamp assembly 10 (close to the vehicle and the road surface near the vehicle, with reference to FIG. 6), while high intensity light (characterized by the short images described above) may be focused farther from the headlamp assembly 10 (far from the vehicle and the road surface far from the vehicle, with reference to FIG. 6).
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Patent Grant
10151439
