大功率白光LED器件及照明灯具的热设计与光设计-材料加工工程专业论文.docx

摘 要 大功率白光 LED 因其具有低电压、低能耗、长寿命、高可靠性等优 点，而有望成为第四代照明光源，但是热设计和光设计上的不成熟性制约了 其在照明领域的推广。 利用有限元分析的方法从 LED 器件和芯片的角度研究了散热结构中各 因素对散热性能的影响，其中包括热沉尺寸、热扩散层以及侧面热扩散等。 利用正交设计的方法分析了常用肋片型和针肋型散热热沉各参数对散热系统 的影响规律，并得出了这两种结构的最优化参数。 本文提出了一种带凹槽铜基板强化热扩散的结构，从有限元和试验两个 角度验证了其可行性，并将其应用到 LED 投射灯的组装当中，最后的测试 结果验证了这种结构的实际散热效果。 使用 Tracepro 光学仿真软件以及正交设计的方法详细分析了旋转抛物 面反射体的各因素，并得出了焦距对法向光强和半强度角的影响趋势。得出 了通过两个 LED 照度分布估算间距的方法，并将其应用于估算 M×N LED 阵列的间距，解决了难于直接用照度分布函数求解间距的问题，但结果的准 确性受到 LED 阵列大小的影响。 关键词 LED；热沉；散热基板；凹槽；反射体 Abstract High-power white LED due to its advantages, such as low voltage, low energy consumption, long service life, high reliability, and so on, could possibly be the 4th generation illuminating light, but the immaturity of thermal and optical designs has restricted its generalization in illuminating field. The influence of parameters of the heat dissipating structure, including heat sink dimension, heat spreading layer and lateral heat dissipation, has been investigated by using finite element analysis in the sense of LED device and chip. Moreover, orthogonal test has been applied into the analysis of rule of parameters of the laminar and pin rib, and optimum results have been arrived. A heat spreading structure of copper heat spreader with indent has been proposed, the feasibility of which has been verified by using finite element analysis and experiment. Test results of LED projector lamp using this structure have confirmed the heat dissipating efficiency of the structure. By using the optical simulation software Tracepro and orthogonal test, parameters of parabolic reflector have been analyzed in detail, and the rule of focal length’s influence on normal luminous intensity and half-intensity angle has been obtained. The method of approximating the clearance by analyzing the illuminance function of double LEDs has been applied into M×N LED array, avoiding the difficulty in resolving clearance of array directly, but the accuracy of result could be affected by the size of LED array. Key wo