CN103363418B

CN103363418B - The microlens array type headlamp of LED automobile illumination

Info

Publication number: CN103363418B
Application number: CN201310330109.7A
Authority: CN
Inventors: 王洪; 陈赞吉; 葛鹏
Original assignee: South China University of Technology SCUT
Current assignee: South China University of Technology SCUT
Priority date: 2013-07-31
Filing date: 2013-07-31
Publication date: 2016-01-06
Anticipated expiration: 2033-07-31
Also published as: CN103363418A

Abstract

The invention discloses a microlens array type headlight for LED automobile lighting, which includes an LED chip, an aluminum substrate and a heat sink, and also includes a collimator and a free-form surface microlens array. The LED chip is welded on the aluminum substrate, the aluminum substrate, The collimator and the free-form surface micro-lens array are installed on the heat sink, the light-emitting surface of the LED chip faces the incident surface of the collimator, and the light exits the collimator as a parallel beam, and is perpendicular to the incident surface of the free-form surface micro-lens array . The microlens array type headlight for LED automobile lighting provided by the present invention has few spare parts, simple and stable structure, easy installation, high heat dissipation efficiency, and does not need a light barrier for light distribution, which reduces the loss of light energy of the light distribution system , improve the utilization rate of light energy; the free-form surface optical design can effectively control the light direction, suppress the glare effect, and at the same time meet the light distribution requirements of the national standard GB25991-2010 for automotive LED headlights.

Description

Microlens Array Type Headlamps for LED Automotive Lighting

技术领域technical field

本发明涉及LED汽车前照灯照明技术领域，特别涉及LED汽车照明用的微透镜阵列型前照灯。The invention relates to the technical field of LED automobile headlight lighting, in particular to a microlens array type headlight for LED automobile lighting.

背景技术Background technique

LED光源具有寿命长、高效节能、体积小、环保等优点，目前已经在车辆的刹车灯、转向灯、尾灯以及仪表用灯等方面广泛得到应用，在前照灯应用上的研究也越来越多，LED即将成为车灯光源市场的主流。随着LED在车辆照明系统中的应用不断扩展，应用技术的不断提高，LED必将逐渐取代传统的白炽灯和卤钨灯，成为车灯的“第四代”光源，这也将是今后车辆照明应用的发展趋势。LED light sources have the advantages of long life, high efficiency and energy saving, small size, and environmental protection. At present, they have been widely used in vehicle brake lights, turn lights, tail lights, and instrument lights. Research on the application of headlights is also increasing. More, LED will soon become the mainstream of the car light source market. With the continuous expansion of the application of LED in vehicle lighting systems and the continuous improvement of application technology, LED will gradually replace traditional incandescent lamps and halogen tungsten lamps and become the "fourth generation" light source of vehicle lights. The development trend of lighting application.

由于LED相比于其他光源，发光特性有很大的差别，芯片阵列的排布和灯具结构的设计都会影响到最终效果，使LED光源应用于摩托车前照灯时要面临更加复杂的光学设计问题。目前，使用得比较广泛的是投射式LED前照灯设计，这种光学设计可以形成很好的光型效果，但在近光灯设计时还需加上挡光板，整个光学系统复杂，光能利用率较低。Compared with other light sources, LEDs have very different luminous characteristics, the arrangement of the chip array and the design of the lamp structure will affect the final effect, making LED light sources face more complex optical design when applied to motorcycle headlights question. At present, the projected LED headlight design is widely used. This optical design can form a good light effect, but it needs to add a light baffle when designing the low beam. The entire optical system is complex and the light energy Utilization is low.

发明内容Contents of the invention

本发明针对上述存在的问题，提供了LED汽车照明用的微透镜阵列型前照灯，该前照灯不需要挡光板，光学系统仅包括LED芯片、抛物面反射器和自由曲面微透镜阵列，解决了投射式LED前照灯设计光能利用率较低的问题，同时能满足国家标准GB25991-2010对汽车用LED前照灯的配光要求。本发明采用如下技术方案：The present invention aims at the above-mentioned problems, and provides a microlens array type headlight for LED automobile lighting. It solves the problem of low utilization rate of light energy in the design of projected LED headlights, and at the same time, it can meet the light distribution requirements of the national standard GB25991-2010 for automotive LED headlights. The present invention adopts following technical scheme:

LED汽车照明用的微透镜阵列型前照灯，包括LED芯片、铝基板和散热器，其还包括准直器和自由曲面微透镜阵列，LED芯片焊接在铝基板上，铝基板、准直器和自由曲面微透镜阵列安装于散热器上，LED芯片的发光面朝向准直器的入射面，光线经准直器后以平行光束出射，并垂直入射自由曲面微透镜阵列的入射面。Microlens array headlamps for LED automotive lighting, including LED chips, aluminum substrates and radiators, and also include collimators and free-form surface microlens arrays, LED chips are welded on aluminum substrates, aluminum substrates, collimators and the free-form surface micro-lens array are installed on the heat sink, the light-emitting surface of the LED chip faces the incident surface of the collimator, and the light exits as a parallel beam after passing through the collimator, and is perpendicular to the incident surface of the free-form surface micro-lens array.

进一步的，所述准直器采用抛物面反射器。Further, the collimator adopts a parabolic reflector.

进一步的，所述散热器包括散热器主体和布设于散热器主体背面的鳍片式结构，LED光源通过铝基板安置于该散热器的主体上，通过散热器主体背面的鳍片式结构能更好地将LED光源工作时产生的热量传导并散发到空气中。良好的散热条件保证了LED光源能在正常环境温度工作的基础上，结合二次光学部件的优化设计使LED汽车前照灯达到配光性能要求。同时，热量的及时散发出去，才不会导致LED芯片性能的变化与衰减，提高车灯的使用寿命，保障了驾驶的安全性。Further, the heat sink includes a heat sink body and a fin structure arranged on the back of the heat sink body, the LED light source is placed on the body of the heat sink through an aluminum substrate, and the fin structure on the back of the heat sink body can be more The heat generated when the LED light source is working is well conducted and dissipated into the air. Good heat dissipation conditions ensure that the LED light source can work at normal ambient temperature, combined with the optimized design of the secondary optical components, the LED automotive headlights can meet the light distribution performance requirements. At the same time, the timely dissipation of heat will not cause the change and attenuation of the performance of the LED chip, improve the service life of the lamp, and ensure the safety of driving.

进一步的，所述抛物面反射器由电镀塑胶材料制成，反射器的内表面是抛物面，构成光学反射面。抛物面反射器的作用是将LED芯片发出的光进行准直配光，使光线经过抛物面反射器反射后以平行光束射出。Further, the parabolic reflector is made of electroplated plastic material, and the inner surface of the reflector is a paraboloid, forming an optical reflection surface. The function of the parabolic reflector is to collimate and distribute the light emitted by the LED chip, so that the light is reflected by the parabolic reflector and emitted as a parallel beam.

进一步改进的，自由曲面光学微透镜阵列由光学透明材料制成，自由曲面光学微透镜阵列将经过准直器准直后的光再次进行配光，产生的光型能满足国家标准GB25991-2010对汽车用LED前照灯的配光要求。Further improved, the free-form surface optical microlens array is made of optically transparent materials, and the free-form surface optical microlens array redistributes the light collimated by the collimator, and the generated light pattern can meet the national standard GB25991-2010 pair Light distribution requirements of LED headlights for automobiles.

进一步改进的，所述自由曲面微透镜阵列由若干个自由曲面微透镜紧凑排列布满整个所述平行光束的截面构成。As a further improvement, the free-form surface micro-lens array is composed of several free-form surface micro-lenses compactly arranged to cover the entire section of the parallel light beam.

进一步改进的，所有自由曲面微透镜为一体形成；所述自由曲面微透镜的入射面为平面，出射面为自由曲面；所述自由曲面微透镜的入射面为矩形平面。As a further improvement, all the free-form surface microlenses are integrally formed; the incident surface of the free-form surface micro-lens is a plane, and the exit surface is a free-form surface; the incident surface of the free-form surface micro-lens is a rectangular plane.

进一步改进的，所述自由曲面微透镜的出射面即自由曲面确定如下：As a further improvement, the exit surface of the free-form surface microlens, namely the free-form surface, is determined as follows:

LED光源发出的光采用准直器进行准直，LED光源发出的光经过准直后以平行光束射出，该光束的截面为半圆形，在该半圆内选取一个微小区域，该微小区域的照度是视为等照度；该微小区域内的光经过透镜在照明面上形成一个等照度的光斑，根据能量守恒定律有：The light emitted by the LED light source is collimated by a collimator. After being collimated, the light emitted by the LED light source is emitted as a parallel beam. The cross section of the beam is a semicircle. Select a small area in the semicircle. It is regarded as equal illuminance; the light in this tiny area passes through the lens to form a spot of equal illuminance on the illuminating surface, according to the law of energy conservation:

E_o·S_o＝E_v·S_v E _o ·S _o ＝E _v ·S _v

E_o表示出射平行光束某一小区域内的照度值，S_o表示该微小区域的面积，E_v表示照明面上光斑的照度值，S_v表示该光斑的面积，则E_v可表示为：E _o represents the illuminance value in a small area of the outgoing parallel light beam, S _o represents the area of the small area, E _v represents the illuminance value of the spot on the illuminating surface, and S _v represents the area of the light spot, then E _v can be expressed as:

E_v＝E_o·tE _v =E _o ·t

式中t为微小区域的面积S_o与光斑的面积S_v的比值；In the formula, t is the ratio of the area S _o of the tiny area to the area S _v of the spot;

然后，依据对LED汽车前照灯的配光要求，照明面上形成一个非等照度的光斑；首先令整个LED汽车前照灯的光轴为z轴，那么xoy平面为照明面，对照明区域进行网格划分；在x轴的方向上均匀划分成m列，在y轴的方向上均匀划分成n行，对每一小格进行编号，其中第i列第j行小格的编号为G_(i,j)，则照明面上第i列的能量为：Then, according to the light distribution requirements of LED automobile headlights, a non-uniluminous light spot is formed on the lighting surface; firstly, the optical axis of the entire LED automobile headlights is the z-axis, then the xoy plane is the lighting surface, and the lighting area Carry out grid division; in the direction of the x-axis, it is evenly divided into m columns, and in the direction of the y-axis, it is evenly divided into n rows, and each small cell is numbered, where the number of the i-th column and the j-th row of the small cell is G _(i,j) , then the energy of column i on the illuminated surface is:

${Q Q}_{((i i,, 00))} = = {Σ Σ}_{j j = = 11}^{n no} {E E.}_{v v} \cdot \cdot {k k}_{((i i,, j j))} \cdot \cdot {S S}_{((i i,, j j))}$

同时，上述等式要满足：At the same time, the above equation must be satisfied:

${E E.}_{v v} \cdot &Center Dot; {S S}_{v v} = = {Σ Σ}_{i i = = 11}^{m m} {Q Q}_{((i i,, 00))}$

上面两式中，S_(i,j)表示照明面上G_(i,j)的面积；根据国家标LED汽车前照灯的配光要求设置照度控制因子k_(i,j)来控制照明面上指定区域的照度值大小，用以形成满足标准的照度分布，E_v·k_(i,j)表示照明面上G_(i,j)的照度值，k_(i,j)的取值大小需根据照明面上照度要求进行设定，对于照度越大的区域k_(i,j)的取值越大，对于照度越小的区域k_(i,j)的取值越小；In the above two formulas, S _{(i, j)} represents the area of G _{(i, j)} on the lighting surface; according to the light distribution requirements of the national standard LED automobile headlights, the illuminance control factor k _{(i, j)} is set to control the lighting surface The illuminance value of the specified area above is used to form an illuminance distribution that meets the standard. E _v k _{(i, j)} represents the illuminance value of G _{(i, j)} on the illuminated surface, and the value of k _{(i, j)} It needs to be set according to the illuminance requirements on the lighting surface. For areas with greater illuminance, the value of k _{(i, j)} is larger, and for areas with smaller illuminance, the value of k _{(i, j)} is smaller;

照明面上第j行的能量为：The energy of row j on the illuminated surface is:

${Q Q}_{((00,, j j))} = = {Σ Σ}_{i i = = 11}^{m m} {E E.}_{v v} \cdot \cdot {k k}_{((i i,, j j))} \cdot \cdot {S S}_{((i i,, j j))}$

${E E.}_{v v} \cdot \cdot {S S}_{v v} = = {Σ Σ}_{j j = = 11}^{n no} {Q Q}_{((00,, j j))}$

然后对应于照明面上的网格划分，通过能量守恒定律对出射平行光束的一个微小小区域进行网格划分，令该微小区域为长为a、宽为b的微小矩形区域；首先对该微小矩形区域进行列划分，对应于照明面上第i列的能量分布，根据能量守恒定律，该微小矩形区域第i列的能量为：Then, corresponding to the grid division on the illumination surface, a tiny area of the outgoing parallel light beam is grid-divided by the law of energy conservation, and the tiny area is made into a tiny rectangular area with a length of a and a width of b; first, the tiny area The column division of the rectangular area corresponds to the energy distribution of the i-th column on the lighting surface. According to the law of energy conservation, the energy of the i-th column in the tiny rectangular area is:

E_o·b·p_i＝Q_(i,0) E _o b p _i =Q _(i,0)

式中，p_i为该微小矩形区域第i列的宽度，联合上述几式可求解出p_i；In the formula, p _i is the width of the i-th column of the tiny rectangular area, and p _i can be obtained by combining the above formulas;

同理，对该微小矩形区域进行行划分，根据能量守恒定律，该微小矩形区域第j行的能量为：Similarly, the tiny rectangular area is divided into rows, and according to the energy conservation law, the energy of the jth row of the tiny rectangular area is:

E_o·a·q_j＝Q_(0,j) E _o · a · q _j = Q _(0,j)

式中，q_j为该微小矩形区域第j行的宽度，联合上述几式求解出q_j；由这两个等式计算得到的p_i和q_j完成该微小矩形区域的网格划分；同样的，对每一小格进行编号，其中第i列第j行小格的编号为g_(i,j)；In the formula, q _j is the width of the jth row of the tiny rectangular area, and q _j is obtained by combining the above formulas; p _i and q _j calculated by these two equations complete the grid division of the tiny rectangular area; , each cell is numbered, wherein the number of the cell in the i-th column and row j is g _{(i, j)} ;

最后，根据照明区域和光束截面微小矩形区域的网格划分，利用折射定律计算微透镜的自由曲面，微透镜对入射到微小矩形区域的光线进行配光，使照明面上形成满足照明标准的光斑，微小矩形区域内g_(i,j)与照明面上G_(i,j)相对应。Finally, according to the grid division of the illumination area and the micro-rectangular area of the beam cross-section, the free-form surface of the micro-lens is calculated by using the law of refraction. , g _{(i, j) in the tiny rectangular area corresponds to G (i, j)} _on the illuminated surface.

将该自由曲面设为微透镜的出射面，做成一个入射面为平面的微透镜，再对若干个这样的微透镜进行阵列排布，排列布满整个入射平行光束的截面，并组合成一个实体，即可得到LED汽车前照灯用的自由曲面微透镜阵列。The free-form surface is set as the exit surface of the microlens, and a microlens with a flat incident surface is made, and then several such microlenses are arranged in an array to cover the entire cross-section of the incident parallel beam, and combined into a Entities, the free-form surface microlens array for LED automobile headlights can be obtained.

与现有技术相比，本发明具有如下优点和技术效果：本发明提供的LED汽车照明用的微透镜阵列型前照灯零配件少、结构简单稳定、便于安装、散热效率高、而且不需要挡光板进行配光，减少了配光系统对光能的损耗，提高了光能利用率；采用自由曲面光学设计，可以有效控制光线走向，抑制眩光效应，同时又能达到国家标准GB25991-2010对汽车用LED前照灯的配光要求，而且自由曲面微透镜阵列的每一个微透镜都是独立的，而且能形成多种形状的光斑，设计灵活性高。Compared with the prior art, the present invention has the following advantages and technical effects: the microlens array type headlamp for LED automotive lighting provided by the present invention has fewer spare parts, simple and stable structure, easy installation, high heat dissipation efficiency, and does not require The light distribution of the light baffle reduces the loss of light energy of the light distribution system and improves the utilization rate of light energy; the free-form surface optical design can effectively control the direction of light and suppress the glare effect, and at the same time meet the national standard GB25991-2010 The light distribution requirements of LED headlights for automobiles, and each microlens of the free-form surface microlens array is independent, and can form various shapes of light spots, with high design flexibility.

附图说明Description of drawings

图1为实施方式中LED汽车前照灯的结构爆炸图。Fig. 1 is an exploded view of the structure of an LED automobile headlight in an embodiment.

图2为实施方式中LED汽车前照灯的配光原理示意图。Fig. 2 is a schematic diagram of the light distribution principle of the LED automobile headlight in the embodiment.

图3为实施方式中近光灯的照明区域网格划分示意图。Fig. 3 is a schematic diagram of grid division of the illumination area of the low beam lamp in the embodiment.

图4为实施方式中平行光束内的微小矩形区域网格划分示意图。Fig. 4 is a schematic diagram of grid division of a tiny rectangular area in a parallel light beam in an embodiment.

图5为实施方式中照明区域和微小矩形区域的能量对应示意图。Fig. 5 is a schematic diagram of the energy correspondence between the illuminated area and the tiny rectangular area in the embodiment.

图6a、图6b分别为实施方式中微透镜实体的两种不同视角的三维示意图。Fig. 6a and Fig. 6b are respectively three-dimensional schematic diagrams of two different viewing angles of the microlens entity in the embodiment.

图7为实施方式中自由曲面微透镜阵列的三维示意图。FIG. 7 is a three-dimensional schematic diagram of a free-form surface microlens array in an embodiment.

图8a为实施方式中LED芯片、铝基板和散热器的安装示意图；Figure 8a is a schematic diagram of the installation of LED chips, aluminum substrates and heat sinks in the embodiment;

图8b为实施方式中铝基板和散热器的结构示意图。Fig. 8b is a schematic structural diagram of an aluminum substrate and a heat sink in an embodiment.

图9为实施方式中LED芯片和抛物面反射器的安装示意图。Fig. 9 is a schematic diagram of the installation of the LED chip and the parabolic reflector in the embodiment.

图10a、图10b为实施方式中LED汽车前照灯的两种不同视角的整灯安装结构示意图。Fig. 10a and Fig. 10b are schematic diagrams of the installation structure of the LED automobile headlight in two different viewing angles in the embodiment.

具体实施方式detailed description

下面结合附图和具体实施方式对本发明作进一步详细的说明，但本发明的实施和保护不限于此。The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, but the implementation and protection of the present invention are not limited thereto.

如图1所示，本发明提供的LED汽车照明用的微透镜阵列型前照灯是由LED芯片100、铝基板200、散热器300、抛物面反射器400和自由曲面微透镜阵列500组成的。LED芯片焊接在铝基板固定的位置上，铝基板、抛物面反射器和自由曲面微透镜阵列通过相应的装配方式安装于散热器上。As shown in FIG. 1 , the microlens array type headlamp for LED automotive lighting provided by the present invention is composed of LED chip 100 , aluminum substrate 200 , radiator 300 , parabolic reflector 400 and freeform surface microlens array 500 . The LED chip is welded on the fixed position of the aluminum substrate, and the aluminum substrate, the parabolic reflector and the free-form surface microlens array are installed on the heat sink through corresponding assembly methods.

本发明提供的LED汽车照明用的微透镜阵列型前照灯配光原理如图2所示，该前照灯不需要挡光板，光学系统仅包括LED芯片100、抛物面反射器400和自由曲面微透镜阵列500。抛物面反射器由电镀塑胶材料制成，反射器的内表面是抛物面，构成光学反射面。抛物面反射器的作用是将LED芯片发出的光进行准直配光，使光线经过抛物面反射器反射后以平行光束射出。自由曲面光学微透镜阵列由光学透明材料制成，自由曲面光学微透镜阵列将经过抛物面反射器准直后的光再次进行配光，产生的光型能满足国家标准GB25991-2010对汽车用LED前照灯的配光要求。The light distribution principle of the microlens array type headlamp for LED automobile lighting provided by the present invention is shown in Fig. lens array 500 . The parabolic reflector is made of electroplated plastic material, and the inner surface of the reflector is a parabolic surface, which constitutes an optical reflective surface. The function of the parabolic reflector is to collimate and distribute the light emitted by the LED chip, so that the light is reflected by the parabolic reflector and emitted as a parallel beam. The free-form optical microlens array is made of optically transparent materials. The free-form optical microlens array redistributes the light collimated by the parabolic reflector, and the light pattern produced can meet the national standard GB25991-2010 for automotive LED front The light distribution requirements of the lighting.

因此，自由曲面光学微透镜阵列500的光学设计是本发明里面的重点，下面将主要讲述自由曲面光学微透镜阵列的光学设计。由于国家标准GB25991-2010对LED汽车前照灯的近光和远光都进行了配光要求，特别对近光的要求比较严苛，则该具体实施方式以近光的设计为例进行说明。Therefore, the optical design of the free-form surface optical microlens array 500 is the focus of the present invention, and the following will mainly describe the optical design of the free-form surface optical microlens array. Since the national standard GB25991-2010 imposes light distribution requirements on both low beam and high beam of LED automotive headlamps, especially the low beam requirements are relatively strict, this specific implementation will be described by taking the design of low beam as an example.

首先，对照明区域进行网格划分，如图3所示。依据国家标准GB25991-2010对LED汽车前照灯近光的配光要求，照明面上要形成一个非等照度的不对称光斑。先设定整个光学系统的光轴为z轴，那么xoy平面为照明面。对照明区域进行网格划分，在x轴的方向上均匀划分成m列，在y轴的方向上均匀划分成n行，对每一小格进行编号，例如第i列第j行小格的编号为G_(i,j)。当然，网格划分得越小，即m和n的数值越大，计算的精度会越高。照明面上第i列的能量为：First, mesh the lighting area, as shown in Figure 3. According to the national standard GB25991-2010 on the low beam light distribution requirements of LED automotive headlights, an asymmetric light spot with non-equal illuminance should be formed on the lighting surface. First set the optical axis of the entire optical system as the z-axis, then the xoy plane is the illumination plane. Divide the lighting area into a grid, divide it evenly into m columns in the direction of the x-axis, and evenly divide it into n rows in the direction of the y-axis, and number each small grid, for example, the grid of the i-th column and the j-th row Numbered G _(i,j) . Of course, the smaller the grid division is, that is, the larger the values of m and n, the higher the calculation accuracy will be. The energy of column i on the illuminated surface is:

${Q Q}_{((i i,, 00))} = = {Σ Σ}_{j j = = 11}^{n no} {E E.}_{v v} \cdot \cdot {k k}_{((i i,, j j))} \cdot &Center Dot; {S S}_{((i i,, j j))}$

${E E.}_{v v} \cdot \cdot {S S}_{v v} = = {Σ Σ}_{i i = = 11}^{m m} {Q Q}_{((i i,, 00))}$

上面两式中，E_v表示照明面上光斑的平均照度值，S_v表示该光斑的面积，S_(i,j)表示照明面上G_(i,j)的面积；根据国家标准GB25991-2010，设置照度控制因子k_(i,j)来控制照明面上指定区域的照度值大小，用以形成满足标准的照度分布，则E_v·k_(i,j)表示照明面上G_(i,j)的照度值，k_(i,j)的取值大小需根据照明面上照度要求进行设定，如对于照度越大的区域k_(i,j)的取值越大，对于照度越小的区域k_(i,j)的取值越小。In the above two formulas, E _v represents the average illuminance value of the light spot on the lighting surface, S _v represents the area of the light spot, and S _{(i, j)} represents the area of G _{(i, j)} on the lighting surface; according to the national standard GB25991-2010 , set the illuminance control factor k _(i,j) to control the illuminance value of the specified area on the lighting surface to form an illuminance distribution that meets the standard, then E _v k _(i,j) means G _(i ,j) on the lighting surface The illuminance value of _j) , the value of k _{(i, j)} needs to be set according to the illuminance requirements of the lighting surface, for example, the larger the value of k _{(i, j)} for the area with larger illuminance, the smaller the illuminance The smaller the value of the region k _(i,j) is.

同理，照明面上第j行的能量为：Similarly, the energy of row j on the illuminated surface is:

${Q Q}_{((00,, j j))} = = {Σ Σ}_{i i = = 11}^{m m} {E E.}_{v v} \cdot &Center Dot; {k k}_{((i i,, j j))} \cdot \cdot {S S}_{((i i,, j j))}$

然后，对应于照明面上的网格划分，通过能量守恒定律对入射平行光束的一个小区域进行网格划分，为了方便计算，该小区域设定为长为a（如8mm），宽为b（如4mm）的矩形。根据能量守恒关系计算完成该微小矩形区域的网格划分。例如，对应于照明面上第i列的能量分布，根据能量守恒定律，该微小矩形区域第i列的能量为：Then, corresponding to the grid division on the illumination surface, a small area of the incident parallel light beam is grid-divided by the law of energy conservation. For the convenience of calculation, the small area is set to have a length of a (such as 8mm) and a width of b (eg 4mm) rectangle. According to the energy conservation relationship, the grid division of the tiny rectangular area is completed. For example, corresponding to the energy distribution of the i-th column on the illuminated surface, according to the energy conservation law, the energy of the i-th column in the tiny rectangular area is:

E_o·b·p_i＝Q_(i,0) E _o b p _i =Q _(i,0)

式中，E_o表示出射平行光束某一小区域内的照度值，p_i为该微小矩形区域第i列的宽度，联合上述几式可求解出p_i。In the formula, E _o represents the illuminance value in a small area of the outgoing parallel beam, p _i is the width of the i-th column in the tiny rectangular area, and p _i can be obtained by combining the above formulas.

E_o·a·q_j＝Q_(0,j) E _o · a · q _j = Q _(0,j)

式中，q_j为该微小矩形区域第j行的宽度，联合上述几式可求解出q_j。由这两个等式计算得到的p_i和q_j可以完成该微小矩形区域的网格划分。同样的，对每一小格进行编号，例如第i列第j行小格的编号为g_(i,j)，如图4所示，其中半圆形虚线边框为入射平行光束的范围。In the formula, q _j is the width of the jth row of the tiny rectangular area, and q _j can be obtained by combining the above formulas. The p _i and q _j calculated by these two equations can complete the grid division of the tiny rectangular area. Similarly, number each small cell, for example, the number of the small cell in column i and row j is g _{(i, j)} , as shown in Figure 4, where the semicircular dashed border is the range of the incident parallel beam.

最后，根据照明区域和微小矩形区域的网格划分，可以利用折射定律计算微透镜的自由曲面，微透镜对入射到微小矩形区域的光线进行配光，使照明面上形成满足照明标准的光斑，微小矩形区域内g_(i,j)与照明面上G_(i,j)相对应，如图5所示。Finally, according to the grid division of the lighting area and the tiny rectangular area, the free-form surface of the microlens can be calculated by using the law of refraction. G _{(i, j)} in the tiny rectangular area corresponds to G _{(i, j)} on the illuminated surface, as shown in Fig. 5 .

在迭代计算时，首先需要确定一个计算的起始点，例如，以微小矩形区域内g_(1,1)的中心点为起始点，g_(1,1)对应着照明面上G_(1,1)，通过g_(1,1)中心点的坐标和G_(1,1)中心点的坐标可以得到出射光线的方向向量，利用折射定律计算可以得出g_(1,1)中心点的法向向量，从而确定该点的切平面，该切平面与入射到g_(1,2)中心点的光线相交从而确定下一个计算点，通过这个计算点的坐标和G_(1,2)中心点的坐标可以得到下一个出射光线的方向向量，再通过上述的计算方法求出该点的切平面和再下一个计算点，以此类推，通过计算机迭代可得出所有计算点的坐标，由这一系列计算点可拟合成微透镜的自由曲面5011，如图6a、图6b所示。In the iterative calculation, it is first necessary to determine a calculation starting point, for example, take the center point of g _(1,1) in the tiny rectangular area as the starting point, and g _(1,1) corresponds to G _{(1,1 )} , the direction vector of the outgoing light can be obtained by the coordinates of the center point of g _(1,1) and the coordinates of the center point of G _(1,1) , and the normal direction of the center point of g _(1,1) can be obtained by calculating the law of refraction Vector, so as to determine the tangent plane of this point, the tangent plane intersects the ray incident to the center point of g _(1,2) to determine the next calculation point, through the coordinates of this calculation point and the center point of G _(1,2) The coordinates can be used to obtain the direction vector of the next outgoing ray, and then the tangent plane of the point and the next calculation point can be obtained through the above calculation method, and so on, and the coordinates of all calculation points can be obtained through computer iteration. The series of calculation points can be fitted into the free-form surface 5011 of the microlens, as shown in Fig. 6a and Fig. 6b.

将迭代计算得到自由曲面5011设为微透镜的出射面，做成一个入射面为平面5012的微透镜501，如图6所示。对该微透镜进行阵列排布，排列布满整个入射平行光束的半圆形截面，并组合成一个实体模型，即可得到LED汽车前照灯用的自由曲面微透镜阵列500，如图7所示。The free-form surface 5011 obtained through the iterative calculation is set as the outgoing surface of the microlens, and a microlens 501 whose incident surface is a plane 5012 is made, as shown in FIG. 6 . Arrange the microlenses in an array to cover the entire semicircular section of the incident parallel light beams, and combine them into a solid model to obtain a free-form surface microlens array 500 for LED automobile headlights, as shown in Figure 7 Show.

散热器300包括散热器主体和布设于散热器主体背面的鳍片式结构，LED芯片100通过铝基板200安置于该散热器主体上，通过散热器主体背面的鳍片式结构将LED光源工作时产生的热量传导并散发到空气中，如图8a、图8b所示。良好的散热条件保证了LED光源能在正常环境温度工作的基础上，结合二次光学部件的优化设计使LED摩托车前照灯达到配光性能要求。同时，热量的及时散发出去，才不会导致LED芯片性能的变化与衰减，提高车灯的使用寿命，保障了驾驶的安全性。The heat sink 300 includes a heat sink body and a fin structure arranged on the back of the heat sink body. The LED chip 100 is placed on the heat sink body through the aluminum substrate 200, and the LED light source is operated through the fin structure on the back of the heat sink body. The generated heat is conducted and dissipated into the air, as shown in Fig. 8a, Fig. 8b. Good heat dissipation conditions ensure that the LED light source can work at normal ambient temperature, combined with the optimized design of the secondary optical components, the LED motorcycle headlight can meet the light distribution performance requirements. At the same time, the timely dissipation of heat will not cause the change and attenuation of the performance of the LED chip, improve the service life of the lamp, and ensure the safety of driving.

抛物面反射器400和自由曲面微透镜阵列500通过相应的装配方式安装于散热器300上，其中，抛物面反射器的焦点位于LED芯片100发光面的中心处，如图9所示，自由曲面微透镜阵列的入射平面垂直于经抛物面反射器反射后射出的平行光束，如图10a、图10b所示。The parabolic reflector 400 and the free-form surface microlens array 500 are installed on the heat sink 300 through a corresponding assembly method, wherein the focus of the parabolic reflector is located at the center of the light-emitting surface of the LED chip 100, as shown in FIG. 9 , the free-form surface microlens The incident plane of the array is perpendicular to the parallel light beam reflected by the parabolic reflector, as shown in Fig. 10a and Fig. 10b.

以上对本发明所提供的LED汽车照明用的微透镜阵列型前照灯进行了详细介绍，该LED汽车前照灯零配件少、结构简单稳定、便于安装、散热效率高、而且不需要挡光板进行配光，减少了配光系统对光能的损耗，提高了光能利用率；采用自由曲面光学设计，可以有效控制光线走向，抑制眩光效应，同时又能达到国家标准GB25991-2010对汽车用LED前照灯的配光要求，而且自由曲面微透镜阵列的每一个微透镜都是独立的，而且能形成多种形状的光斑，设计灵活性高。本发明中应用了各种模型图对具体实施方式进行了阐述，以上所述仅为本发明较佳可行的实施例子而已。对于本领域的技术人员，依据本发明的思想，在具体实施方式及应用范围上均会有改善之处。综上所述，本说明书内容不应理解为对本发明的限制。The microlens array type headlight for LED automobile lighting provided by the present invention has been introduced in detail above. The LED automobile headlight has few spare parts, simple and stable structure, easy installation, high heat dissipation efficiency, and does not need a light barrier The light distribution reduces the loss of light energy of the light distribution system and improves the utilization rate of light energy; the free-form surface optical design can effectively control the direction of light and suppress the glare effect, and at the same time meet the national standard GB25991-2010 for automotive LEDs The light distribution requirements of the headlights, and each microlens of the free-form surface microlens array is independent, and can form a variety of shapes of light spots, with high design flexibility. Various model diagrams are used in the present invention to illustrate specific implementation methods, and the above descriptions are only preferred and feasible implementation examples of the present invention. For those skilled in the art, according to the idea of the present invention, there will be improvements in the specific implementation and application range. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. Microlens array type headlights for LED automotive lighting, including LED chips, aluminum substrates and heat sinks, characterized in that they also include collimators and free-form surface microlens arrays, LED chips are welded on aluminum substrates, aluminum substrates , the collimator and the free-form surface micro-lens array are installed on the radiator, the light-emitting surface of the LED chip faces the incident surface of the collimator, and the light exits as a parallel beam after passing through the collimator, and is perpendicular to the incident surface of the free-form surface micro-lens array surface; the free-form surface microlens array is composed of several free-form surface micro-lenses compactly arranged to cover the cross-section of the entire parallel light beam; all free-form surface micro-lenses are integrally formed; the incident surface of the free-form surface micro-lens is a plane, The exit surface is a free-form surface; the incident surface of the free-form microlens is a rectangular plane; the exit surface of the free-form microlens is the free-form surface determined as follows:

The light emitted by the LED light source is collimated by a collimator. After being collimated, the light emitted by the LED light source is emitted as a parallel beam. The cross section of the beam is a semicircle. Select a small area in the semicircle. It is regarded as equal illuminance; the light in this tiny area passes through the lens to form a spot of equal illuminance on the illuminating surface, according to the law of energy conservation:

E _o ·S _o ＝E _v ·S _v

E _o represents the illuminance value in a small area of the outgoing parallel light beam, S _o represents the area of the small area, E _v represents the illuminance value of the spot on the illuminating surface, and S _v represents the area of the light spot, then E _v can be expressed as:

E _v =E _o ·t

In the formula, t is the ratio of the area S _o of the tiny area to the area S _v of the spot;

Then, according to the light distribution requirements of LED automobile headlights, a non-uniluminous light spot is formed on the lighting surface; firstly, the optical axis of the entire LED automobile headlights is the z-axis, then the xoy plane is the lighting surface, and the lighting area Carry out grid division; in the direction of the x-axis, it is evenly divided into m columns, and in the direction of the y-axis, it is evenly divided into n rows, and each small cell is numbered, where the number of the i-th column and the j-th row of the small cell is G _(i,j) , then the energy of column i on the illuminated surface is:

{Q Q}_{((i i,, 00))} = = {Σ Σ}_{j j = = 11}^{n no} {E E.}_{v v} \cdot \cdot {k k}_{((i i,, j j))} \cdot \cdot {S S}_{((i i,, j j))}

At the same time, the above equation must be satisfied:

{E E.}_{v v} \cdot &Center Dot; {S S}_{v v} = = {Σ Σ}_{i i = = 11}^{m m} {Q Q}_{((i i,, 00))}

In the above two formulas, S _{(i, j)} represents the area of G _{(i, j)} on the lighting surface; according to the light distribution requirements of the national standard LED automobile headlights, the illuminance control factor k _{(i, j)} is set to control the lighting surface The illuminance value of the specified area above is used to form an illuminance distribution that meets the standard. E _v k _{(i, j)} represents the illuminance value of G _{(i, j)} on the illuminated surface, and the value of k _{(i, j)} It needs to be set according to the illuminance requirements on the lighting surface. For areas with greater illuminance, the value of k _{(i, j)} is larger, and for areas with smaller illuminance, the value of k _{(i, j)} is smaller;

The energy of row j on the illuminated surface is:

{Q Q}_{((00,, j j))} = = {Σ Σ}_{j j = = 11}^{m m} {E E.}_{v v} \cdot \cdot {k k}_{((i i,, j j))} \cdot &Center Dot; {S S}_{((i i,, j j))}

At the same time, the above equation must be satisfied:

{E E.}_{v v} \cdot &Center Dot; {S S}_{v v} = = {Σ Σ}_{j j = = 11}^{n no} {Q Q}_{((00,, j j))}

Then, corresponding to the grid division on the illumination surface, a tiny area of the outgoing parallel light beam is grid-divided by the law of energy conservation, and the tiny area is made into a tiny rectangular area with a length of a and a width of b; first, the tiny area The column division of the rectangular area corresponds to the energy distribution of the i-th column on the lighting surface. According to the law of energy conservation, the energy of the i-th column in the tiny rectangular area is:

E _o b p _i =Q _(i,0)

In the formula, p _i is the width of the i-th column of the tiny rectangular area, and p _i can be obtained by combining the above formulas;

Similarly, the tiny rectangular area is divided into rows, and according to the energy conservation law, the energy of the jth row of the tiny rectangular area is:

E _o · a · q _j = Q _(0,j)

In the formula, q _j is the width of the jth row of the tiny rectangular area, and q _j is obtained by combining the above formulas; p _i and q _j calculated by these two equations complete the grid division of the tiny rectangular area; , each cell is numbered, wherein the number of the cell in the i-th column and row j is g _{(i, j)} ;

Finally, according to the grid division of the illuminated area and the small rectangular area of the beam cross section, the free-form surface of the microlens is calculated using the law of refraction.

2. The microlens array headlamp for LED automotive lighting according to claim 1, wherein the collimator adopts a parabolic reflector.

3. The microlens array type headlamp for LED automotive lighting according to claim 1, wherein the radiator includes a radiator body and a fin structure arranged on the back of the radiator body, and the LED light source passes through the aluminum radiator. The substrate is arranged on the main body of the radiator.

4. The microlens array headlamp for LED automotive lighting according to claim 2, wherein the parabolic reflector is made of electroplated plastic material, and the inner surface of the reflector is a paraboloid, forming an optical reflection surface.

5. The microlens array headlamp for LED automotive lighting according to claim 1, characterized in that the free-form optical micro-lens array is made of optically transparent material, and the free-form optical micro-lens array will be collimated through the collimator The straight light is distributed again, and the generated light type can meet the light distribution requirements of the national standard GB25991-2010 for LED headlights for automobiles.