Design Of Headlight Optical System Based On Double Free-form Surface Lens

Nowadays,with the continuous development of the times,automotive technology has become more and more mature with the market demand,and its safety,functionality and convenience have become urgent needs of people's lives.The headlight of a car as the "eye" of a car at night must ensure sufficient lighting and the safety and comfort of the driver.The high power and stable color temperature of white LEDs provide the necessary guarantee for safe driving of the car,but there are still disadvantages.The emission spectrum of high-power white LEDs is mainly concentrated in the blue and yellow light bands.When light of different wavelengths passes through the optical lens,the light will separate and cause dispersion,which will cause the color temperature of the spot to be unstable.The human eye is more sensitive to blue and yellow light.Long-term gaze will cause visual fatigue and the driver 's driving presence Great security risks.Aiming at this drawback,this paper designs a new double free-form surface lens optical system to effectively improve the dispersion problem.First,this paper re-optimizes the double free-form surface that can achieve uniform illumination,calculates the mapping relationship between the light emitted by the LED light source and the receiving surface,establishes equations,solves discrete points,and uses three-dimensional software modeling to construct a free-form surface.The simulation results show that The light can be redistributed,the light intensity can be accurately distributed and the luminous angle can be controlled,the color temperature of the spot can be stabilized,the illumination of the target area can be excessively smooth,the dispersion problem in the lamp system can be solved,and the safety of the car at night can be improved.Secondly,in order to solve the problem of low efficiency of traditional projection modules,the ellipsoidal mirror in the design of the optical system is optimized,and the collimator unit structure that efficiently focuses and collimates the ellipsoidal mirror is replaced.It is verified by experiments that Collimator can effectively collect and collimate light beams,and the light utilization rate reaches more than 80%,which greatly improves the light utilization rate.Finally,the optical system is simulated and checked for regulations.Check whether the light pattern distribution and color temperature requirements meet the requirements of the national standard,and get test results that meet the requirements of the corresponding regulations.By comparing and analyzing the inspection reports of the optical system,it can be seen that the maximum illuminance values of the far and near light of the traditional optical system are 86 lx and 25 lx,and the efficiency of the optical system is 56.7%;The efficiency of the optical system is 72.2%.The results show that this new optical design not only meets the purpose of suppressing dispersion,but also improves the system light efficiency utilization rate by about 15%,which verifies the rationality and feasibility of this design.