- 學位論文
高功率照明用發光二極體之一次光學透鏡設計最佳化及製程規劃
Optimum Design and Manufacturing Process of the Lens of a High Power Light Emitting Diode for Illumination
摘要
本研究的目的在於設計一個照明用高功率發光二極體的一次光學(透鏡與光源間沒有其他介質)透鏡及其製程規劃。照明用的發光二極體的透鏡設計目標是盡量使光照度均勻分佈，又要盡量使所有的光線都能射到目標區。然而發光二極體的發光特性為朗伯型的放射，本研究之方法為利用光路折射、反射與全反射等原理互相搭配組合的機制來嘗試達到射出光源均勻的目的，小偏折角度的光線先將其引導到外圍，而大偏折角度的光線則引導其往前集中收斂；透鏡曲面的輪廓的設計則使用了精準的設計機制與電腦輔助計算，並進行了初步的實驗。除上述之外還要兼顧到透鏡量產製造的可能性，因為成本考量而要設計射出成型模具，所以要在兼顧光學表現的情形之下將透鏡的輪廓修改成可以射出成型的幾何外型，再進行了第二階段的實驗。發光二極體的光源為面光源，本研究發現透鏡的設計無法完全滿足面光源上每一點的輸出需求，所以必須以最佳化的方式來權衡出透鏡輪廓的最佳解。
並列摘要
The purpose of this research is to design a first-order（without other medium between lens and light source）lens of a high power light emitting diode(LED) for illumination. The manufacturing process of designed lens is also studied. The lens is designed to make the lights distributed on the objective surface as uniform as possible. The optical character of the light emitted from LED chip is lambertian emitting. The design algorithm of the light uniformity is obtained by means of reflection, total reflection and refraction. By using the optical mechanisms described above, we divided the light ray into small-angle ( light between optical axis ) light zone, and large-angle light zone. The computer is used to do the precise calculation to design the profile of the lens. To prove the design results is practical, several experiment are completed. In addition,, the production method is also considered. Considering the design of injection mold, the geometry and profile of the lens is modified and the optical performance of the modified lens is almost same as the original design. After the real lens fabricated, optical experiment is also proceeded. It is noted that due to the light of LED is not a point light source, therefore, the designed lens cannot reflect and refract every light ray in optimized way. It is necessary to use the optimum method to find the best lens profile.