本論文以LED螢光粉層的光學結構為重點，以初階的光學模擬搭配實驗驗證，探討穿透式與反射式螢光粉結構，在LED封裝光學結構的效率變化。在穿透式螢光粉架構提出環形螢光粉白光LED架構，由一倒錐透鏡與透鏡側面圍繞呈環形的螢光粉層結構組成，我們優化倒錐半角相對臨界條件，降低螢光粉反射回之光線被晶粒吸收的機率，獲得螢光粉封裝萃取效率達94%。並找到克服大晶粒中信漏藍光之臨界條件。因中間全反射面上方(螢光粉反射)，與螢光粉側面(螢光粉穿透)之出光機制不同，其B/Y很難一致，加上全反射面光滑度的影響，故有空間分布色溫差異大之缺點。因此進一步提出改善架構，反射環形螢光粉白光LED架構。在反射式的螢光粉結構中，提出在螢光粉反射層加入反射材料-硫酸鋇(BaSO4)，並以不同配比試片，驗證出單一螢光粉獲得高演色性的機制(CCT 5500K， CRI 80附近)。最後將倒錐半角臨界條件透鏡設計結合上述機制，應用在2×2 mm2 晶粒的螢光粉白光LED架構，成功驗證出兼具高效率，與高演色性的螢光粉光學結構。In this thesis, we analysis the package efficiency and the CRI based on the different phosphor-packaged LEDs. First, we design an inverted cone lens with its side of the lens around a ring phosphor layer structure in the transmissive package for the phosphor layer. The optimized lens not only reduces chip absorption probability of phosphor layer emission light but also enhances the package extraction efficiency. Second, we discuss about the LEDs with the reflective package for the phosphor layer. We mixed BaSO4 and phosphor in the reflective case. We find out the condition high color rendering index due to different proportions with phosphor and BaSO4. Finally, we make several samples of white LED products based on our result. We successfully get the LEDs with high efficiency and high color rendering index and verify our simulation.
