The subject matter herein generally relates to vehicle lighting and a vehicle headlamp with a projection lens.
Vehicle headlamps can comprise light sources, reflectors, and shields. The light source emits light. The reflector reflects light towards an opening of the reflector. The shield blocks a portion of the light to form a desired light pattern having a cut-off line, thereby preventing glare to from distracting a driver in an oncoming vehicle. However, the light efficiency is reduced due to the light shielded by the shield.
Implementations of the present technology will now be described, by way of example only, with reference to the attached figures.
It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the exemplary embodiments described herein. However, it will be understood by those of ordinary skill in the art that the exemplary embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the exemplary embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure.
The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series, and the like.
The light source 11 emits light. In the exemplary embodiment, the light source 11 is a light emitting diode (LED).
The reflector 12 can be substantially bowl-shaped. The reflector 12 comprises a concave inner reflecting surface 121 and an opening 123 formed by an edge of the inner reflecting surface 121. The inner reflecting surface 121 comprises a bottom portion 1210. The light source 11 is received in the reflector 12 and connected towards the bottom portion 1210. The reflector 12 reflects the light emitted by the light source 11 towards the opening 123.
The projection lens 13 covers the opening 123 of the inner reflecting surface 121. The projection lens 13 comprises a first light incident surface 131 facing the light source 11 and a first light emitting surface 132 facing away from the first light incident surface 131. In the exemplary embodiment, the first light incident surface 131 and the first light emitting surface 132 are flat. In other embodiments, the first light incident surface 131 can be concaved towards the first light emitting surface 132, and the first light emitting surface 132 can be convexed away from the first light incident surface 131.
Referring to
A plurality of strips 1341 protrudes from the diffusing surface 134. In the exemplary embodiment as shown in
In the exemplary embodiment, the strips 1341 can be integrally formed with the diffusing surface 134 of the projection lens 13. The reflective index of each strips 1341 can be equal to that of the projection lens 13. In other embodiments, the strips 1341 can be connected to the diffusing surface 134 through a transparent adhesive (not shown). The reflective index of the transparent adhesive is equal to that of each strips 1341 and the projector lens 13.
The rough surface 133 is formed by a coarsening, grinding, or sand-blasting process. As such, the rough surface 133 can scatter the light passing through the rough surface 133 in all directions, thereby decreasing the intensity of the light passing through the rough surface 133 and preventing glare from distracting a driver in an oncoming vehicle. A desired light pattern having a cut-off line can be formed.
In other embodiments, the first light incident surface 131 can also be a roughed surface formed by a coarsening, grinding, or sand-blasting process.
With the above configuration, the strips 1341 can diffuse the light passing through the diffusing surface 134 to transversely elongate the light pattern generated by the light source 11, which allowing the light pattern to meet the Standard Specification for vehicle lamps. The rough surface 133 can scatter the light passing through the rough surface 133 in all directions, thereby decreasing the intensity of the light passing through the rough surface 133 and preventing glare from distracting a driver in an oncoming vehicle, and finally forming a desired light pattern having a cut-off line. Since no shields are needed, the efficiency of light output is improved.
The secondary lens 24 is received in the reflector 22. The secondary lens 24 can be substantially bowl-shaped and cover the light source 21. The secondary lens 24 can diffuse the light emitted by the light source 21. In the exemplary embodiment, the secondary lens 24 comprises a second light incident surface 242 facing the light source 21, a second light emitting surface 243 facing away from the second light incident surface 242, and a bottom surface 241 connecting the second light incident surface 242 and the second light incident surface 242. The second light incident surface 242 and the second light emitting surface 243 convex away from the light source 21, thereby defining a receiving space 244 for receiving the light source 21.
The first light emitting surface 232 further comprises another rough surface 233 positioned below the diffusing surface 234, that is, the diffusing surface 234 is positioned between the two first portions 233. An area of the rough surface 233 positioned above the diffusing surface 234 is greater than an area of the rough surface 233 positioned below the diffusing surface 234.
Even though information and advantages of the present exemplary embodiments have been set forth in the foregoing description, together with details of the structures and functions of the present exemplary embodiments, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the present exemplary embodiments, to the full extent indicated by the plain meaning of the terms in which the appended claims are expressed.
Number | Date | Country | Kind |
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105111687 | Apr 2016 | TW | national |