Research On The Optical System Of Anti-glare Smart LED Headlights

As an important functional part of a car,headlights ensure the safety of driving at night.However,the traditional headlamp lighting method is single and fixed,and there is a safety hazard,especially the high beam is very easy to cause traffic accidents.With the development of technology,the integration of LED light sources in automobile headlights has begun to develop in the direction of intelligence and diversification.Adaptive front-lighting system(AFS)and adaptive driving beam(ADB)have been proposed successively.However,these two systems are relatively complex in structure,difficult to design,high in preparation cost,and have a small market share,and cannot really improve the dazzling problem of most vehicles.For this reason,this paper combines the LED light source to carry out optical design,and researches the headlamp optical system to solve the driving safety problems such as car light dazzling and lighting blind area,so as to ensure the realization of intelligent lighting function to the greatest extent,and the system structure is simple,low cost,and has certain practical significance.In this paper,the headlamp optical system type is interpreted and analyzed.First,a projection optical system with good lighting effect and easy to manufacture is selected as the design scheme of the low beam part of the headlamp.Combining the law of refraction and reflection and the principle of optical mirroring,the ellipsoidal reflector,baffle and aspheric lens are designed to achieve a narrow and wide low-beam type with a clear 45° cut-off line.The integrated design of the baffle and the heat dissipation base not only reduces the complexity of the system structure,facilitates the installation and use of the light source and lens in the later stage,but also ensures the clear low beam effect and prevents glare.The overall low beam system has a compact structure,small size,and a light efficiency of 61.7%,which meets the requirements of GB 25991-2010.At the same time,the corner lamp is designed to supplement the illumination,so as to solve the problem of small illumination range in the near light.The corner lamp design is completed by directly reflecting light from the free-form surface,which improves the utilization rate of the light source.The overall corner lamp simulation light efficiency is as high as 72%,and the relevant test values meet the legal requirements.Compared with the AFS system,this solution does not require a mechanical structure,which ensures the stability of the system reduces the design difficulty and costs less,and is easily accepted by the market.Secondly,for the high beam part of the headlight,by analyzing the adaptive high beam regulation ECE R123,combined with the current traffic situation of China driving on the right,the A part specified in the regulation is selected as the main test and design basis.Then the light distribution screen is divided into 10 areas according to needs,using 10 LED light sources for corresponding lighting,and designing with reference to the mainstream matrix scheme: the light guide column was designed based on the principle of total reflection to reduce the light interference between the light sources and enable the light emitted by the light source to be transmitted to the predetermined position;at the same time,a Fresnel-like lens is designed to achieve the effect of partitioned lighting when the light travels through multiple different curved surfaces.Considering the difficulty of post-finished product production and related functional design,the high beam part adopts a distributed design,that is,three lenses are selected to correspond to a part of the illumination area.The light type superposition realizes the ADB function,and the anti-glare effect is presented by adjusting the brightness and darkness of the light source in different areas,and the overall system light efficiency reaches 42%.In addition,in view of the problem that the adaptive high-beam light type obtained is narrow and cannot meet the basic high-beam lighting function,the corresponding high-beam supplementary light design is given,that is,the free-form surface reflection is used to superimpose the light spot,and the final model passes the legal test.It not only meets the anti-glare requirements of smart headlights,but also meets the high beam system of basic high beam lighting.The overall high beam system has a simple structure and a good realization effect,which is convenient for later product development.