CN113669686A

CN113669686A - Optical device for vehicle headlamp, headlamp and vehicle

Info

Publication number: CN113669686A
Application number: CN202010414010.5A
Authority: CN
Inventors: 张帆; 张震; 王龙; 李建功
Original assignee: Osram Continental Ltd
Current assignee: Osram Continental Ltd
Priority date: 2020-05-15
Filing date: 2020-05-15
Publication date: 2021-11-19

Abstract

The present invention relates to an optical device for a vehicle headlamp, comprising a light source, a primary optical unit, a secondary optical unit, and a light source located between the primary optical unit and the secondary optical unit in the direction of travel of the vehicle. A light shield extending in a horizontal direction, characterized in that the light source and the primary optical unit are placed in a direction facing the secondary optical unit, so that most of the light beams generated by the light source pass through the primary optical unit in parallel The secondary optical unit is emitted in the forward direction of the vehicle or in the extending direction of the visor. The invention also relates to a headlamp and a vehicle.

Description

Optical device for vehicle headlamp, headlamp and vehicle

Technical Field

The present invention relates to an optical device for a vehicle headlamp. The invention further relates to a headlight and a vehicle.

Background

Most of the optical functions of vehicle headlamps are achieved by optical devices equipped with lighting, which comprise a light source, a primary lens, a visor and a secondary lens. To ensure the illumination efficiency and output of the optical device, the secondary lens preferably employs a larger illumination opening. Currently, more and more Original Equipment Manufacturers (OEMs) tend to use smaller sized lenses (with smaller illumination openings) for optical equipment of vehicle headlamps. This directly poses challenges to the design of optical devices, particularly those with larger light spread angles and more compact profile structures.

An optical device for a vehicle headlamp is known from the prior art, for example, from document CN 206522705U, an optical device system for forming a low beam light type is known, which includes an LED light source and an outer lens, a horizontally disposed light shielding plate is disposed between the LED light source and the outer lens, the LED light source is disposed above the light shielding plate and is disposed obliquely, so that light emitted from the LED light source obliquely irradiates on the light shielding plate, the light shielding plate is disposed above the bottom of the outer lens, the low beam light type can be realized in a projection manner by means of the optical device, a transparent plastic lens is disposed in front of the light source, and light emitted from the light source is projected onto the lens, and then passes through a matched baffle and the outer lens after being reflected and refracted, and finally forms the low beam light type. The low beam type formed by the optical equipment is smooth and clear, the light distribution is uniform, the light utilization rate is high, and the optical equipment is a very practical projection type low beam design. In this optical device system, the outer lens has a relatively large size, for example, having a height of more than 50 mm. The size of the light incident surface and/or the light emergent surface of the outer lens is larger, and particularly the size of the outer lens in the height direction of the vehicle is larger, so that the size of the whole headlamp is larger. Accordingly, the head lamp needs to provide a large space for arranging the optical device. Meanwhile, the inclined arrangement of the LED light source cannot adapt to an outer lens with a smaller size, especially a lower height, and cannot realize a larger illumination diffusion angle.

It follows that the above-described optical device system belongs to the optical device systems known in the art having a relatively large size (large illumination opening). Meanwhile, the components of the optical device system cannot accommodate the outer lens having a smaller size, and a larger illumination spread angle cannot be achieved by its configuration. Therefore, with the increasing competition, the demands of customers for optical equipment with small size, high illumination efficiency and large illumination spread angle cannot be met, that is, the light beams cannot be efficiently projected with a large illumination width and a small space size.

Disclosure of Invention

An object of the present invention is to provide an optical apparatus for a vehicle headlamp which has a small size and can achieve efficient projection of a light beam with a large irradiation width.

According to the invention, an optical device for a vehicle headlight is provided, comprising a light source, a primary optical unit, a secondary optical unit and a visor located between the primary optical unit and the secondary optical unit in the direction of travel of the vehicle and extending in the horizontal direction, the light source and the primary optical unit being positioned directly opposite the secondary optical unit in such a way that a large part of the light beam generated by the light source passes through the primary optical unit and impinges on the secondary optical unit parallel to the direction of travel of the vehicle or the direction of extension of the visor. The expression "direction facing the secondary optic" herein means that the light source and the primary optic are not obliquely arranged, or that the light exit surface of the primary optic is substantially facing the light entrance surface of the secondary optic, or that the section of the primary light exit surface of the primary optic is substantially parallel to the light entrance surface of the secondary optic. The "majority of the light beams" herein refers to greater than or equal to 80% of the light beams, preferably greater than or equal to 90% of the light beams, and further preferably greater than or equal to 95% of the light beams.

An advantage of the present invention is that an optical module having high illumination efficiency, a larger illumination width, and a smaller size is realized by the arrangement of the light source, the primary optical unit, and the light shielding plate. In general, in the case where the secondary optical unit is small in size, it is difficult for the optical apparatus known in the related art to achieve high efficiency of projection of the light beam and a large irradiation width. In the present invention, especially by the reasonable arrangement of the positions of the light source and the primary optical unit, the light beam emitted by the light source can be reasonably, uniformly and completely emitted into the light incident surface of the secondary optical unit, especially the light incident surface with a smaller size in the height direction, through the primary optical unit, and then projected into the corresponding area in front of the vehicle through the light emergent surface of the secondary optical unit. Since the light source and the primary optical element are arranged in a directly opposite direction to the secondary optical element, rather than being arranged at an angle, as is known from the prior art, a large portion of the light beam generated by the light source, i.e. for example more than 80%, passes through the primary optical element and is directed to the secondary optical element parallel to the direction of travel of the vehicle or the direction of extension of the aperture plate. Therefore, the light beams can be completely and uniformly incident to the opposite secondary optical units with higher efficiency, and simultaneously, the light diffusion angle is increased as much as possible, so that the purpose of increasing the irradiation width is achieved.

The height of the secondary optical unit is preferably less than or equal to 30 mm. Such a high secondary optical unit is not common in the prior art. More importantly, the arrangement of the light source, the light shielding plate and the primary optical unit in the prior art cannot match the height of the secondary optical unit, so that efficient, uniform and wide-width projection of the light beam cannot be realized. The optical device according to the invention overcomes the technical problem that the optical devices known in the prior art do not project a light beam evenly and completely to a long and narrow illumination opening. Because the optical equipment is small in size, the space of the vehicle headlamp can be saved, the arrangement of the vehicle headlamp is optimized, and the flexibility of the design of the vehicle headlamp is increased, so that more solutions can be provided according to different customer requirements. In addition, the optical equipment with smaller size is also beneficial to the light weight of the vehicle headlamp, is beneficial to the light weight of the whole vehicle, and realizes the increase of the vehicle endurance and the reduction of the fuel consumption.

Preferably, the light shield is located in part of the beam path and is used to reflect these beams projected onto it to the secondary optical unit. The light shielding plate can not only block light rays to form a light and shade cut-off line, but also reflect light beams to the upper side of the secondary optical element, so that the illumination efficiency is improved, and the color unevenness is reduced. Compared with the light source and the primary optical unit which are obliquely arranged in the prior art, the light source and the primary optical unit are arranged in the direction right facing the front of the vehicle, so that the incident angle and the emergent angle of the light beam emitted to the light shielding plate are increased, the diffusion angle of the light is further increased, and the irradiation width is increased.

Preferably, the shadow mask has a metal-polished coated surface. Further preferably, the light-shielding plate having a surface with a metal polish coating has a reflectance of 60% or more. The metal polished coating surface can increase the illumination efficiency and realize the high-efficiency projection of light beams.

Alternatively or additionally, the shade panel is provided with a projection extending in the vehicle advancing direction at an intermediate position in the vehicle lateral direction. Since the optical system is designed for headlights with a large spread angle of illumination, the secondary optical unit does not control well all the light beams impinging on it, which causes some stray light to obscure the cut-off line, in particular the middle region of the cut-off line. The projection is thus used to correct the sharpness of the central region of the cut-off line, so that a better lighting effect is achieved.

Preferably, the primary optical unit has a plurality of lenses, in particular 7 lenses, arranged next to one another in the transverse direction of the vehicle, wherein one of the lenses, which is located in the middle in the transverse direction of the vehicle, has a light-transmitting surface at its lower part, which extends downward below the sun visor, to which part of the light beam generated by the light source is directed and, after reflection by the light-transmitting surface, is projected via the region below the sun visor onto the secondary optical unit. A further beam path is thus provided and is located below the shutter plate, which ensures a more complete and uniform projection of the light beam onto the secondary optical unit. These light beams may be used to project a light distribution illuminating the top side.

Further preferably, the light-transmitting surface has at least one, preferably a plurality of columnar light-transmitting surfaces. Through setting up this column printing opacity face, can improve the light distribution in vehicle the place ahead, improve the degree of consistency of light distribution.

Alternatively or additionally, at least one of the remaining lenses of the primary optical unit, excluding the intermediate lens, has a light-transmitting surface extending horizontally thereunder, which is higher than the light-shielding plate and serves to totally reflect the light beam projected thereon. The distance between the light-transmitting surface and the shading plate in the height direction of the vehicle is less than or equal to 5 mm. By reducing the distance between the lens of the primary optical unit and the light shielding plate in the vehicle height direction, the light loss of the light irradiated from the primary optical unit to the light shielding plate is reduced, and the illumination efficiency of the light beam reflected by the light shielding plate is further improved, so that the light beam is efficiently projected.

It is also advantageous if the light-transmitting surface of the lens of the primary optical unit, which surface extends horizontally on the underside thereof, is planar. Preferably, a lower portion of the lens of the primary optical unit having a substantially circular or elliptical shape as viewed from the front of the vehicle has a light transmitting surface formed by, for example, cutting. By cutting the optically inactive lower portion of the lens of the primary optical unit, on the one hand, the distance between the lens of the primary optical unit and the light shielding plate in the vehicle height direction can be reduced to further increase the light irradiation efficiency, and on the other hand, the size of the lens of the primary optical unit in the vehicle height direction can be reduced to reduce the size of the entire optical apparatus.

Alternatively or additionally, a distance between a light exit surface on the vehicle front side of the plurality of lenses and the light shielding plate in the vehicle advancing direction is less than or equal to 10 mm. This can also reduce optical loss of light irradiated to the light-shielding plate by the primary optical unit, improving the illumination efficiency of the light beam reflected by the light-shielding plate.

Alternatively, the light-shielding plate and the primary optical unit are integrally made of the same material, preferably by injection molding. Thus, the step of adjusting the positions of the light shielding plate and the primary optical unit can be omitted, faster assembly can be achieved, and the installation cost can be reduced. Alternatively, the light shielding plate may also be placed obliquely as the case may be.

The lens of the primary optical unit may be made of a plastic material such as Polycarbonate (PC). Alternatively, glass, silicone or polymethyl methacrylate (PMMA) may also be used, for example.

In addition, the secondary optical unit is a biconvex lens. Generally, the lens functions to deflect light to compensate for aberrations. Compared with the plano-convex lens used in the prior art, the biconvex lens provides two positive focal powers, and compared with the plano-convex lens, the biconvex lens has an effective curvature variable when focusing a light path, and can be matched with a light shielding plate with a certain tangent plane radian and a light emergent surface of the lens to eliminate aberration. Meanwhile, the use of the biconvex lens can ensure that the emitted light distribution has a proper cut-off line in the vertical direction, which helps to enlarge the illumination diffusion angle in the horizontal direction, thereby increasing the illumination width.

The lenticular lens may be made of a plastic material such as glass or Polymethylmethacrylate (PMMA). Alternatively, for example, silicone or Polycarbonate (PC) may also be used.

Preferably, the light source is used for generating a low beam light beam, i.e. the optical device is used for projecting a low beam light. Alternatively, the light source is used to generate a high beam light beam, i.e. the optical device is used to project a high beam.

The light sources may be Light Emitting Diodes (LEDs), and/or organic LEDs (oleds), and/or laser diodes and/or lighting means acting according to the laser activated non-contact phosphor principle (LARP), and/or halogen lamps, and/or gas discharge type bulbs (high intensity discharge (HID)), and/or be designed in combination with projectors acting according to the Digital Light Processing (DLP) principle, respectively. Thus, a number of alternatives for the light source of the present invention are provided.

It is also conceivable that the optical device may be a module for a so-called matrix headlamp with LEDs or groups of LEDs arranged in a row or matrix. It fulfils the function of an adaptive lamp. Each individual LED or group of LEDs in a module can be individually controlled to turn them on, off, or dim. In particular, in conjunction with the camera system and image processing electronics and/or other sensors, it is possible to identify oncoming and oncoming vehicles ahead and to at least partially turn off or dim the respective LED or group of LEDs. Due to the high pixels, objects (pedestrians, animals or obstacles) recognized by the camera system can also be illuminated separately, so that the driver is made aware of them.

Here, the LEDs may be arranged in a single row or a plurality of rows, and thus the LEDs may be arranged in a column or a matrix, which respectively form one light emitting pixel. It is conceivable that each LED corresponds to one or more lenses of the primary optics module, which lenses may likewise be arranged in a row or matrix. It is also contemplated that the lens of one primary optic module may correspond to multiple LEDs or multiple LED groups.

The optical device may be arranged in a headlamp of a vehicle. The headlight and/or the optical device may be used in a vehicle, for example as a headlight on the front side of the vehicle. Therefore, the headlamp with smaller size, high illumination efficiency and large illumination width is realized. Meanwhile, the flexibility of design is increased, and the requirements of different customers are met.

Drawings

Hereinafter, the present invention will be explained in more detail according to examples. Wherein:

figure 1 shows a side view of an optical device according to the invention,

figure 2 shows a side view of a primary optical unit according to the invention,

figure 3 shows a rear view of the primary optical unit according to the invention,

figure 4 shows a front view of a primary optical unit according to the invention,

figure 5 shows a top view of an optical device according to the invention,

figure 6a shows a top view of a visor according to the present invention,

figure 6b shows a partial enlarged view of the projection of the shutter plate according to the invention of figure 6a,

figure 7a shows the cut-off line when the visor is not provided with a protrusion,

figure 7b shows the cut-off line when the visor is provided with a protrusion,

fig. 8 shows the light distribution produced by the optical device according to the invention.

Labeled as: 1. an optical device; 2. a light source; 4. a primary optical unit; 6. a visor; 8. a secondary optical unit; 10. an LED; 12. a lens; 13. 14, a local surface of the light incident surface; 15. a light-transmitting surface; 16. a light-emitting surface; 17. a lens in an intermediate position; 18. a light-transmitting surface; 20. a columnar light-transmitting surface; 22. a biconvex lens; 24. a light incident surface; 26. a light-emitting surface; 28. a protrusion;

Detailed Description

FIG. 1 shows a side view of an optical device according to an embodiment of the invention. The optical apparatus 1 comprises a light source 2, a primary optical unit 4, a shading plate 6 and a secondary optical unit 8. Wherein said light source 2 is preferably a Light Emitting Diode (LED)10 (the position indicated by 10 in fig. 3 corresponds to the position where the LED is placed) and is used for generating a low beam light beam. Alternatively, the Light Emitting Diode (LED)10 may also be used to generate a high beam light beam. According to the present embodiment, as shown in fig. 3, the light source has 7 LEDs 10 arranged side by side in the vehicle lateral direction. Alternatively, other numbers of LEDs may be provided to produce the desired light beam. The light sources 2 may also be in the form of matrix LEDs to emit respective light beams.

As shown in fig. 3 and 4, the primary optical unit 4 preferably includes 7 lenses 12 arranged side by side in the vehicle transverse direction, and the LEDs 10 of the light source 2 correspond to one of the lenses 12, respectively. Alternatively, other numbers of lenses 12 may be provided to match a corresponding number of LEDs 10. These lenses 12 are preferably collimating lenses, which may be made of a plastic material such as Polycarbonate (PC). The lens 12 is substantially circular or elliptical when viewed from the front or rear. These lenses 12, which can be used as total internal reflection, have an entrance face comprising partial surfaces 13, 14, a transmission face 15 extending horizontally at the lower side and an exit face 16 at the front side of the vehicle. The light-transmitting face 1 is planar and may be formed, for example, by cutting. As shown in fig. 2, the lens 17 of these lenses 12, which is located at the center in the vehicle lateral direction, also has a light-transmitting surface 18 extending forward and downward to below the shade 6 at the lower portion thereof. The light-transmitting surface 18 is used to totally reflect the light beam from the light source 2 to the secondary optical unit 8. The light-transmitting surface 18 is provided with a plurality of columnar light-transmitting surfaces 20 as shown in fig. 4.

As shown in fig. 1, the light shielding plate 6 extends in the horizontal direction and has a plate shape. The mask 6 has a metal-polished coated surface. Further preferably, the light-shielding plate having a surface with a metal polish coating has a reflectance of 60% or more. As shown in fig. 5 and 6a, the light-shielding plate 6 has a substantially rectangular shape as viewed from above. The shading plate 6 has a semicircular recess at the side facing the secondary optical unit 8. It is contemplated that the recess may be provided in other shapes. The shape and position of the light shielding plate 6 are determined by the shape and position of the primary optical unit 4 and the secondary optical unit 8. Therefore, the shading plate 6 may also have any other shape that matches the primary optical unit 4 and the secondary optical unit 8. As shown in fig. 1, the light shielding plate 6 is arranged substantially at the position of the light transmitting surface 15 of the lens 12 in the height direction. Preferably, the light shielding plate 6 is disposed below the light transmitting surface 15 in the height direction, and the distance d between the light shielding plate 6 and the light transmitting surface 15 is less than or equal to 5mm, and further preferably, the distance d between the light shielding plate 6 and the light transmitting surface 15 is equal to 3 mm. Further, as shown in fig. 5, the distance s between the light exit surface 16 of the lens 12 of the primary optical unit 4 on the vehicle front side and the light shielding plate 6 in the vehicle advancing direction is preferably less than or equal to 10 mm.

As shown in fig. 1, the height h of the secondary optical unit 8 in the vehicle height direction is smaller and has a substantially flat shape, as compared with the secondary optical units known in the related art. In particular, the secondary optical unit 8 has a biconvex lens 22. The lenticular lens 22 may be made of glass or a plastic material such as Polymethylmethacrylate (PMMA). As shown in fig. 5, the two convex surfaces of the biconvex lens 22 are convex toward the front and the rear of the vehicle, respectively, and have an approximately elliptical shape. It is also conceivable that the biconvex lens 22 has a substantially V-shaped or crescent-shaped form, viewed from above. The convex surface of the biconvex lens 22 facing the rear of the vehicle forms a light incident surface 24, and the convex surface of the biconvex lens 22 facing the front of the vehicle forms a light emitting surface 26. The surface of the light-emitting surface 26 may be further designed and added with a dermatoglyph structure with a certain roughness, so as to soften the sharpness of the cut-off line, i.e. reduce the gradient value, and improve the driving safety at night. The secondary optical unit or the biconvex lens 22 has a substantially rectangular shape as viewed from the front of the vehicle. Specifically, the height h of the secondary optical unit 8, or the light incident surface 24 and/or the light exit surface 26 of the secondary optical unit 8, in the vehicle height direction is less than or equal to 30mm, more preferably less than or equal to 25mm, and still more preferably 24 mm. The width of the secondary optical unit 8 in the vehicle transverse direction may be, for example, 110 mm. Thereby forming an elongated illumination opening extending laterally as viewed from the front of the vehicle.

As fig. 1 and 5 show, the light beam emitted by the light source 2 or LED 10 according to the invention enters the primary optical unit 4 or lens 12 via the entry surfaces 13, 14. The majority of the generated light beam passes through the exit surface 16 of the primary optical element 4 or of the lens 12 directly into the entry surface 24 of the biconvex lens 22 of the secondary optical element 8. As shown in fig. 5, the arrangement of the lenses 12 of the primary optical element 4 allows the partial light beam to be completely and uniformly incident into the secondary optical element 8. At the same time, a part of the generated light beam is focused near the focal point F of the lens (see fig. 1 or 5) or incident on the upper surface of the light-shielding plate 6 by reflection on the upper surface of the lens 12 and refraction on the light-emitting surface 16 of the lens 12, and the light beam is incident on the incident surface 24 of the secondary optical unit 8 or the biconvex lens 22 by reflection on the upper surface of the light-shielding plate 6. In addition, a further part of the generated light beams, which are used in particular for generating the illumination of the upper part of the light distribution, impinges on the light-transmitting surface 18 or the cylindrical light-transmitting surface 20 of the lens 12, in particular of the lower side of the intermediate lens 17, and these light beams are totally reflected by the light-transmitting surface 18 or the cylindrical light-transmitting surface 20 and impinge via the lower region of the light-shielding plate 6 on the light-entering surface 24 of the secondary optical unit 8 or of the biconvex lens 22. Finally, the light beam incident on the light incident surface 24 of the secondary optical unit 8 is emitted from the light emitting surface 26 of the secondary optical unit 8, and the final light distribution in the front of the vehicle is formed.

Fig. 7a shows the unsharp cut-off line produced by the above-mentioned optical device 1 when the mask 6 has a flat upper surface. Since the above-described optical device is designed for a large spread angle of the light, the biconvex lens 22 of the secondary optical unit 8 does not guarantee that all light beams are always well controlled. Thus, part of the stray light may obscure the cut-off line, especially the middle part of the bright-dark cut-off line as shown in fig. 7 a. This will have an impact on the final illumination distribution effect.

Therefore, in order to correct the sharpness of the central region of the cutoff line, as shown in fig. 6a and 6b, the light-shielding plate 6 is provided with a projection 28, which extends in the vehicle advancing direction, projecting upward, at an intermediate position in the vehicle lateral direction. By means of this projection 28, the light beam entering the biconvex lens 22 can be better controlled, reducing the generation of stray light which would obscure the cut-off line, thereby increasing the sharpness of the cut-off line produced by the optical device according to the invention. Fig. 7b shows the cut-off line produced by the optical device according to the invention when the shading plate 6 has a protrusion 28. Therein, it is clearly seen that the central part of the cut-off line is no longer blurred.

Fig. 8 shows the light distribution produced by the optical device according to the invention. As can be seen, the light distribution has, in particular, a large illumination width and the illumination is uniform.

Claims

1. An optical apparatus for a vehicle headlamp including a light source, a primary optical unit, a secondary optical unit, and a shade plate extending in a horizontal direction between the primary optical unit and the secondary optical unit in a vehicle traveling direction,

the light source and the primary optical unit are disposed opposite to the secondary optical unit in such a way that most of the light beam generated by the light source passes through the primary optical unit and is emitted to the secondary optical unit parallel to the direction of travel of the vehicle or the direction of extension of the visor.

2. An optical device as claimed in claim 1, characterized in that the shutter is located in the path of the partial light beams generated by the light source for reflecting these light beams incident thereon to the secondary optical unit.

3. The optical apparatus of claim 2 wherein the shutter plate has a metal polished coated surface.

4. The optical apparatus according to claim 2, wherein the light-shielding plate is provided with a projection extending in a vehicle advancing direction at an intermediate position in a vehicle lateral direction.

5. The optical apparatus according to claim 1, wherein the primary optical unit has a plurality of lenses arranged side by side in a vehicle lateral direction, wherein the lens located at a middle position in the vehicle lateral direction has a light-transmitting surface extending downward below the light-shielding plate at a lower portion thereof, and a part of the light beam generated by the light source is incident on the light-transmitting surface and is projected to the secondary optical unit through a region below the light-shielding plate after being reflected by the light-transmitting surface.

6. The optical device of claim 5, said light-transmissive surface having at least one cylindrical light-transmissive surface.

7. The optical apparatus according to claim 5, wherein at least one lens of the remaining plurality of lenses of the primary optical unit other than the lens at the intermediate position has a light-transmitting surface extending horizontally on a lower side thereof, the light-transmitting surface being less than or equal to 5mm in a vehicle height direction from the light-shielding plate.

8. An optical device as claimed in claim 1, characterized in that the secondary optical unit is provided as a biconvex lens.

9. A vehicle headlamp comprising the optical device according to any one of claims 1 to 8.

10. A vehicle having a vehicle headlamp according to claim 9.