太陽能擁有許多優點，包括節能、環保、健康等方面。此外太陽光也具有最好的演色指數，因此能提供人類優良的照明品質。近年來有許多關於自然光應用的研究，而有效將日光運用於室內照明正是本篇論文的重點。
我們利用典型拋物反射鏡收集太陽光，將正向入射的光線聚焦於焦點處，再利用圓形中空導光管將聚焦的光線導引至拋物面兩側。但光的效率會隨著在導光管內傳遞的反射次數而下降，因此我們建立一個數學模型計算光線在導光管內的反射次數，並利用楔型結構來改善其中傳輸效率較低的光線。為了讓太陽集光系統能收集斜向入射的太陽光線，我們決定導光管入光口的孔徑以容許一定範圍內的偏移量。
最後將利用台灣的氣象資訊，設計一個能收集大角度入射光而不需要太陽追蹤系統的複合型拋物集光器。為了得到最良好的收集效率，我們定義兩種狀況去傾斜固定集光器，希望能在可見光範圍節省最大的能量。

Solar energy is clean and reusable. It preserves the environment and good for human health protection. In addition, sunlight has the greatest rendering index which provides the most natural vision effect. Therefore, tremendous researches are contributed to study daylight applications, including indoor illumination, which is the primary focus of our research.
To approach the objective, a parabolic reflector is applied to collect sunlight. When straight sunlight falls onto a correctly aligned parabolic reflector, it will be reflected back towards a focal point, so we apply a circle hollow light pipe to guide the sunlight. Because the efficiency of the guiding depends on the reflection times of rays, we built mathematical model to calculate the times of reflection in a light pipe and added a wedge structure to improve the efficiency. In order to collect more sunlight, when it’s not straight to fall onto parabolic reflector, we design the appropriate dimension of entering hole to allow the departure.
And then, the weather information of Taiwan is considered to design a compound parabolic concentrator that can collect wide range of the incident sunlight without a sun tracking system. For the maximum efficiency, we define two tilted conditions to evaluate the static concentrator with the total saved energy in visible range.

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