CN112443808A - Adaptive head lamp - Google Patents
Adaptive head lamp Download PDFInfo
- Publication number
- CN112443808A CN112443808A CN201910801350.0A CN201910801350A CN112443808A CN 112443808 A CN112443808 A CN 112443808A CN 201910801350 A CN201910801350 A CN 201910801350A CN 112443808 A CN112443808 A CN 112443808A
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- China
- Prior art keywords
- light
- lens
- emitting
- emitting diodes
- light emitting
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
- F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
- F21S41/10—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source
- F21S41/14—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source characterised by the type of light source
- F21S41/141—Light emitting diodes [LED]
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
- F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
- F21S41/20—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by refractors, transparent cover plates, light guides or filters
- F21S41/25—Projection lenses
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21W—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO USES OR APPLICATIONS OF LIGHTING DEVICES OR SYSTEMS
- F21W2102/00—Exterior vehicle lighting devices for illuminating purposes
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21W—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO USES OR APPLICATIONS OF LIGHTING DEVICES OR SYSTEMS
- F21W2107/00—Use or application of lighting devices on or in particular types of vehicles
- F21W2107/10—Use or application of lighting devices on or in particular types of vehicles for land vehicles
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
- F21Y2115/00—Light-generating elements of semiconductor light sources
- F21Y2115/10—Light-emitting diodes [LED]
Abstract
An adaptive headlamp comprises at least one light-emitting module and a central control module. The at least one light-emitting module comprises a first lens, a light-emitting unit and a second lens. The light emitting unit is positioned behind the first lens and comprises a plurality of light emitting diodes which are arranged left and right and face the first light incident surface. The second lens is positioned in front of the first lens and forms a focus curve positioned behind the light emitting diode. Each light emitting diode forms a virtual light source positioned on the focal curve through the first lens, and light rays of the virtual light source are emitted forwards through the first lens and the second lens, so that the projected light rays are focused and concentrated, and the collimation and the illumination brightness of the projected light rays are improved.
Description
Technical Field
The present invention relates to a head lamp, and more particularly, to an Adaptive Driving Beam (ADB) head lamp.
Background
An adaptive headlamp mounted on a vehicle is known, which can adjust the illumination range of the headlamp by detecting the position and distance of a vehicle coming in front, turn off or dim the light directly illuminating the opposite vehicle area, and avoid glare on the vehicle coming in front. Referring to FIG. 1, a vehicle 91 is shown traveling on a road 90 with adaptive headlights positioned to illuminate the road as shown in the gray areas. Referring to fig. 2, when there is another vehicle ahead of the vehicle 91 (fig. 2 shows that the vehicle 91 faces two vehicles 92), the adaptive headlights automatically turn off the lights that would otherwise be illuminated in the area of the facing vehicle 92.
The conventional adaptive head lamp generally includes a plurality of light emitting elements and a lens located in front of the light emitting elements for emitting light of the light emitting elements forward, and although the known adaptive head lamp can prevent glare from occurring in a coming vehicle, its structural design only achieves a basic adaptive dimming function, and does not focus on improving the light emitting collimation and the light emitting brightness of the head lamp, so the improvement is still needed.
Disclosure of Invention
The invention aims to provide an adaptive head lamp which can focus projected light, has better collimation and can improve illumination brightness.
The invention discloses an adaptive headlamp, which comprises at least one light-emitting module and a central control module. The at least one light-emitting module comprises a first lens, a light-emitting unit and a second lens, wherein the first lens comprises a first light-in surface facing backwards and a first light-out surface facing forwards, the light-emitting unit is positioned behind the first lens and comprises a plurality of light-emitting diodes which are arranged left and right and face towards the first light-in surface, the second lens is arranged in front of the first lens at intervals, the second lens forms a focus curve positioned behind the light-emitting diodes, the light of the light-emitting diodes is incident towards the first light-in surface of the first lens, each light-emitting diode generates a virtual light source under the optical action of the first lens, the virtual light sources are arranged on the focus curve, the light of the virtual light sources is emitted forwards through the first lens and the second lens, the central control module is in signal connection with the light-emitting diodes and can carry out independent lighting or extinguishing control or independent light-emitting brightness change on each light-emitting diode, the central control module can control the light emitting diodes corresponding to the vehicles to be turned off or the brightness of the light emitting diodes to be turned down according to the positions and the distances of the vehicles in front.
The adaptive head lamp comprises at least one light-emitting module, a light grating and a light source, wherein the light grating is positioned between the light-emitting unit and the first light incident surface of the first lens, the light grating comprises a plurality of partition walls which are arranged at the left and the right, and a plurality of light channels which are positioned between the partition walls and are separated by the partition walls, and the light channels respectively correspond to the positions of the light-emitting diodes.
The width of each light channel in the left-right direction is 1 mm-3 mm, and the length of each light channel in the up-down direction is 3 mm-10 mm.
The first light-emitting surface of the first lens is provided with a plurality of lens parts which are arranged left and right and respectively correspond to the positions of the light-emitting diodes.
In the adaptive headlamp of the present invention, each lens portion is projected forward.
The adaptive head lamp comprises two light emitting modules arranged on the left and right, wherein the second lenses of the light emitting modules are adjacent to each other on the left and right and are integrally connected, each second lens is a convex lens and is provided with a second light emitting surface facing forwards, and the second light emitting surfaces gradually protrude forwards from the left side and the right side to the center.
In the adaptive headlamp of the present invention, the focal curve of the second lens gradually protrudes backward from the left and right sides toward the center.
The invention has the beneficial effects that: the light emitting diode forms a virtual light source positioned on the focal curve through the first lens, and the light of the virtual light source is emitted forwards through the first lens and the second lens, so that the projected light is focused and concentrated, and the collimation and the illumination brightness of the projected light are improved.
Drawings
Other features and effects of the present invention will become apparent from the following detailed description of the embodiments with reference to the accompanying drawings, in which:
FIG. 1 is a schematic top view illustrating a vehicle mounted with an adaptive headlamp driving on a roadway, with the gray area illustrating the adaptive headlamp illumination area;
FIG. 2 is a schematic view similar to FIG. 1 illustrating several other vehicles present in front of the vehicle, with the gray areas illustrating the adaptive headlamp illumination area;
FIG. 3 is a perspective view of one embodiment of an adaptive headlamp of the present invention;
FIG. 4 is an exploded perspective view of the embodiment;
fig. 5 is a top cross-sectional view of the embodiment, illustrating a focal curve of a second lens of the embodiment, and illustrating light traveling paths of a plurality of light emitting diodes.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and examples.
Referring to fig. 3 to 5, an embodiment of an Adaptive Driving Beam (ADB) headlamp according to the present invention includes two light emitting modules 1 and a central control module 2.
The two light emitting modules 1 are adjacently arranged left and right, and each light emitting module 1 comprises a first lens 3, a light emitting unit 4, a grating 5 and a second lens 6.
The first lens 3 includes a first light incident surface 31 facing backward and a first light emitting surface 32 opposite to the first light incident surface 31 and facing forward. The first light emitting surface 32 has a plurality of lens portions 321 arranged left and right, and each lens portion 321 is a convex lens protruding forward. The first lens 3 is made of, but not limited to, acryl, and the use of acryl has the advantages of low material cost, good molding stability, high precision, and low mold cost.
The light emitting unit 4 is located behind the first lens 3 and includes a substrate 41 and a plurality of light emitting diodes 42 arranged on the substrate 41. The leds 42 face the first light incident surface 31 of the first lens 3 and correspond to the lens portions 321 of the first light emitting surface 32.
The grating 5 of each light emitting module 1 is located between the first lens 3 and the light emitting unit 4, and is a vertical plate extending in the left-right direction. The grating 5 includes a plurality of partitions 51 disposed on the left and right sides, and a plurality of light channels 52 respectively located between the partitions 51 and partitioned by the partitions 51. The light channels 52 respectively correspond to the positions of the light emitting diodes 42 and the lens portions 321 of the first light emitting surface 32. The light channel 52 is through in the front-back direction, and light of the corresponding led 42 can pass through the light channel. In the present embodiment, the grating 5 may be made of plastic material or metal material, and each light channel 52 is, for example, rectangular.
The second lens 6 of each light emitting module 1 is disposed in front of the first lens 3 at intervals, and by proper structural design, the second lens 6 forms a focal curve C behind the light emitting diode 42, the focal curve C is a petzval curve (petzval curve), and infinite points form a line, and the focal curve C is equivalent to a connection line of a plurality of focal points. The second lens element 6 can be regarded as a plurality of lens structures arranged in series along the left-right direction (each lens structure is longitudinally extended), and since each lens structure has a focal point, the second lens element 6 includes a plurality of continuous focal points, thereby forming the focal point curve C. In the embodiment, the second lens 6 is a convex lens and has a second light incident surface 61 facing the first lens 3 and a second light emitting surface 62 facing forward, wherein the second light emitting surface 62 gradually protrudes forward from the left and right sides toward the center, and the second light emitting surface 62 also gradually protrudes forward from the upper and lower sides toward the center. The focus curve C gradually protrudes backward from the left and right sides toward the center.
In the present embodiment, the two light emitting modules 1 are disposed and connected to each other, and specifically, the two first lenses 3 are connected together, the substrates 41 of the two light emitting units 4 are integrally connected, the two gratings 5 are connected together, and the two second lenses 6 are adjacent to each other and integrally connected to each other. By connecting the two light emitting modules 1 together, in particular, the two second lenses 6 are integrally connected rather than being independently separated, manufacturing is facilitated. During assembly, the grating 5 of each light-emitting unit 4 is assembled with the substrate 41 of the light-emitting unit 4, the first lens 3 is assembled and combined on the front side of the grating 5, and the second lens 6 can be connected with the first lens 3 and the grating 5 through a frame body not shown in the figure. In practice, only one light-emitting module 1 may be provided.
The central control module 2 is in signal connection with the light emitting diodes 42 of the two light emitting modules 1, and is internally provided with a preset program, so that each light emitting diode 42 can be independently lightened or extinguished or independently changed in light emitting brightness according to the driving condition.
In the present invention, the light of the led 42 is incident toward the first lens 3 after passing through the light channel 52 of the grating 5. And the light of each led 42 mainly emits to the lens portion 321 of the first lens 3 corresponding to the led 42. Each led 42 generates a virtual light source F through the optical structure and optical action of the first lens 3, and the virtual light sources F of the leds 42 are arranged on the focal curve C, which is equivalent to that a plurality of virtual light sources F are formed on the focal curve C. The light is further emitted forward through the light channel 52 of the grating 5, the first lens 3, and the second lens 6 in sequence, and then projected on the road ahead and becomes the illumination light in compliance with the regulations.
According to the optical principle, the light of a light source arranged at the focus of a convex lens forms parallel light after passing through the convex lens. The invention forms the virtual light source F on the focal curve C after the light emitting diode 42 passes through the optical action of the first lens 3 through the innovative structure and element relative relationship, so that the light projected by the virtual light source F can be focused, concentrated and prevented from spreading after passing through the second lens 6, therefore, the light projected by the invention has better collimation property, illuminates towards a preset road area and can improve the brightness of the car lamp.
In addition, when driving, the central control module 2 can control the light emitting diodes 42 corresponding to the vehicle to be turned off or turned down according to the position and distance of the vehicle in front, and more specifically, the central control module 2 sends an instruction according to the result of judging the position and distance of the vehicle in front to control at least one of the light emitting diodes 42 to be turned off or turned down, and the light emitting diode 42 controlled to be turned off or turned down is the light emitting diode 42 of which the light emitting irradiation range falls in the area where the vehicle is located in front. Therefore, the irradiation brightness of the front vehicle position is low, and glare on the coming vehicle is avoided, so that the function of the adaptive headlamp is realized. The invention has the function of an adaptive headlamp and can meet the visual field requirement of a driver to the maximum extent.
It should be noted that the grating 5 is advantageous in that the light of each led 42 can be emitted forward through the corresponding light channel 52, so that the light can be emitted to the corresponding lens portion 321 in a concentrated manner. The partition walls 51 of the light barrier 5 have a light blocking effect, so that light from the led 42 can be prevented from leaking from the left and right sides when passing through the light channel 52. Therefore, the grating 5 is beneficial to improving the light utilization rate, reducing stray light and achieving the advantage that imaging can be projected more accurately. Preferably, each light channel 52 has a lateral width of 1mm to 3mm and a vertical length of 3mm to 10 mm. In the case where the lateral width and the vertical length are too small, the amount of light that can pass through is too small, and the lateral width and the vertical length are too large, the light is easily leaked and scattered from the left and right sides and the upper and lower sides after passing through the light tunnel 52, and therefore the size of the light tunnel 52 is preferably within the above range. By proper design of the size and shape of the light tunnel 52, the size and shape of the light pattern can be controlled to meet the usage requirement. It should be noted that, the grating 5 can be omitted in the present invention, and the light of the light emitting unit 4 is directly emitted to the first lens 3, so that the effect of forming the virtual light source F on the focal curve C can be achieved as well.
In summary, the light emitting diode 42 forms the virtual light source F on the focal curve C through the first lens 3, and the light of the virtual light source F is emitted forward through the first lens 3 and the second lens 6, so that the projected light can be focused and concentrated to improve the collimation and illumination brightness of the projected light, thereby achieving the objective of the present invention. The first lens 3 and the second lens 6 are a primary lens and a secondary lens, respectively, and the adaptive head lamp combined with the primary lens and the secondary lens is an innovative and practical structure.
The above description is only an example of the present invention, and the scope of the present invention should not be limited thereby, and the invention is still within the scope of the present invention by simple equivalent changes and modifications made according to the claims and the contents of the specification.
Claims (7)
1. An adaptive headlamp comprising: at least one luminous module, and well accuse module, its characterized in that: the at least one light-emitting module comprises a first lens, a light-emitting unit and a second lens, wherein the first lens comprises a first light-in surface facing backwards and a first light-out surface facing forwards, the light-emitting unit is positioned behind the first lens and comprises a plurality of light-emitting diodes which are arranged left and right and face towards the first light-in surface, the second lens is arranged in front of the first lens at intervals, the second lens forms a focus curve positioned behind the light-emitting diodes, the light of the light-emitting diodes is incident towards the first light-in surface of the first lens, each light-emitting diode generates a virtual light source under the optical action of the first lens, the virtual light sources are arranged on the focus curve, the light of the virtual light sources is emitted forwards through the first lens and the second lens, the central control module is in signal connection with the light-emitting diodes and can carry out independent lighting or extinguishing control or independent light-emitting brightness change on each light-emitting diode, the central control module can control the light emitting diodes corresponding to the vehicles to be turned off or the brightness of the light emitting diodes to be turned down according to the positions and the distances of the vehicles in front.
2. The adaptive headlamp of claim 1, wherein: the at least one light-emitting module further comprises a grating positioned between the light-emitting unit and the first light-in surface of the first lens, the grating comprises a plurality of partition walls arranged on the left and right sides, and a plurality of light channels positioned between the partition walls and separated by the partition walls, and the light channels respectively correspond to the positions of the light-emitting diodes.
3. The adaptive headlamp of claim 2, wherein: the width of each light channel in the left-right direction is 1 mm-3 mm, and the length of each light channel in the up-down direction is 3 mm-10 mm.
4. The adaptive headlamp of claim 1, wherein: the first light-emitting surface of the first lens is provided with a plurality of lens parts which are arranged left and right and respectively correspond to the positions of the light-emitting diodes.
5. The adaptive headlamp of claim 4, wherein: each lens portion is protruded frontward.
6. The adaptive headlamp of claim 1, wherein: the adaptive head lamp comprises two light emitting modules which are arranged left and right, wherein the second lenses of the light emitting modules are adjacent left and right and are integrally connected, each second lens is a convex lens and is provided with a second light emitting surface facing forwards, and the second light emitting surfaces gradually protrude forwards from the left side and the right side to the center.
7. The adaptive headlamp of claim 1, wherein: the focus curve of the second lens gradually protrudes backwards from the left side and the right side to the center.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910801350.0A CN112443808A (en) | 2019-08-28 | 2019-08-28 | Adaptive head lamp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910801350.0A CN112443808A (en) | 2019-08-28 | 2019-08-28 | Adaptive head lamp |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112443808A true CN112443808A (en) | 2021-03-05 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910801350.0A Pending CN112443808A (en) | 2019-08-28 | 2019-08-28 | Adaptive head lamp |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112443808A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114754323A (en) * | 2022-04-01 | 2022-07-15 | 东风汽车集团股份有限公司 | ADB light-emitting device based on automobile illumination field of vision expands |
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| US20080316761A1 (en) * | 2005-07-28 | 2008-12-25 | Light Prescriptions Innovators, Llc | Free-Form Lenticular Optical Elements and Their Application to Condensers and Headlamps |
| EP2357399A1 (en) * | 2010-02-16 | 2011-08-17 | Koito Manufacturing Co., Ltd. | Optical unit |
| CN104105921A (en) * | 2012-12-20 | 2014-10-15 | 齐扎拉光系统有限责任公司 | Light-emitting unit for projector lamp |
| CN106555959A (en) * | 2015-09-18 | 2017-04-05 | 堤维西交通工业股份有限公司 | Double lens distance lamp switching car light |
| CN109312903A (en) * | 2016-05-26 | 2019-02-05 | 松下知识产权经营株式会社 | Headlight for automobile and the vehicle for using it |
| CN109606248A (en) * | 2017-10-04 | 2019-04-12 | Zkw集团有限责任公司 | Automobile front lamp |
| CN109668109A (en) * | 2017-10-16 | 2019-04-23 | 法雷奥照明公司 | Lighting module for motor vehicles |
| CN109716016A (en) * | 2016-09-15 | 2019-05-03 | 法雷奥照明公司 | Light emitting module including monolithic electroluminescent source |
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2019
- 2019-08-28 CN CN201910801350.0A patent/CN112443808A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080316761A1 (en) * | 2005-07-28 | 2008-12-25 | Light Prescriptions Innovators, Llc | Free-Form Lenticular Optical Elements and Their Application to Condensers and Headlamps |
| EP2357399A1 (en) * | 2010-02-16 | 2011-08-17 | Koito Manufacturing Co., Ltd. | Optical unit |
| CN104105921A (en) * | 2012-12-20 | 2014-10-15 | 齐扎拉光系统有限责任公司 | Light-emitting unit for projector lamp |
| CN106555959A (en) * | 2015-09-18 | 2017-04-05 | 堤维西交通工业股份有限公司 | Double lens distance lamp switching car light |
| CN109312903A (en) * | 2016-05-26 | 2019-02-05 | 松下知识产权经营株式会社 | Headlight for automobile and the vehicle for using it |
| CN109716016A (en) * | 2016-09-15 | 2019-05-03 | 法雷奥照明公司 | Light emitting module including monolithic electroluminescent source |
| CN109606248A (en) * | 2017-10-04 | 2019-04-12 | Zkw集团有限责任公司 | Automobile front lamp |
| CN109668109A (en) * | 2017-10-16 | 2019-04-23 | 法雷奥照明公司 | Lighting module for motor vehicles |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114754323A (en) * | 2022-04-01 | 2022-07-15 | 东风汽车集团股份有限公司 | ADB light-emitting device based on automobile illumination field of vision expands |
| CN114754323B (en) * | 2022-04-01 | 2023-12-26 | 东风汽车集团股份有限公司 | ADB light-emitting device based on automobile illumination visual field expansion |
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