近年來，環保意識抬頭，綠能產業在全世界越來越被重視。各國產業與學界先進為了健康照明及節約能源，設計出能夠將太陽光導入室內做為照明用的技術，稱為【自然光導光照明系統】。
本文採用透鏡式之太陽集光器來實現自然光導光的目的。透鏡式集光器有高聚光比的特性，但透鏡的太陽光入射角度的容忍度範圍很小，若是平行光相對於透鏡光軸有一傾斜角度，聚焦光點將偏移直射焦點許多，無法將光線導入至導光管中傳播，所以透鏡式太陽集光器通常會搭配太陽追蹤系統，使光線在日照時間內平行透鏡光軸入射。
因此我們提供一種新型結構的靜態式集光器，設計出以導光管中心為圓心，導光管上方一固定距離與固定角度排列多個交錯式的雙層透鏡成半圓弧狀，並進一步優化雙層透鏡成非球面透鏡，使每個第一層透鏡與第二層透鏡負責匯集不同時刻的太陽光，使不同角度的光線經過兩層透鏡後能夠有效的偏折至導光管入光面。
我們參考台灣台北的太陽資訊，包括夏至、春分、秋分及冬至，將集光器向南傾斜兩種角度分別對準夏至與春秋分，模擬集光器與只有導光管收光能力之比較。根據模擬結果，此集光器在日照時間內有穩定的光通量輸出。

In recent years, due to the awareness of environmental protection, the use of green energy gets more and more attention around the world. Industry and academia focus on the use of sunlight to provide indoor lighting and save energy.
One of the structures of solar concentrator is using lens to collect light, which features a high concentration ratio. But the acceptance of incident light angle of lens-type concentrator is quite small. If there is a tilted angle θ between parallel light and optical axis of lens, the focal point shifts from the original position and cannot be guided to light pipe. So the lens-type concentrator usually goes with dynamic sun tracking system to make the optical axis of lens parallel sunlight.
Therefore, we propose a novel static solar concentrator without high-cost sun tracking system, which contains collection and transmission parts; the collection part is the array of interlaced two-layer lenses in semi-circular arrangement and two-layer lenses comprise the first-layer lens at the top and the second-layer lens at the bottom; the transmission part is one acrylic light pipe. Furthermore, we optimize the aspheric coefficients of lens. Each first and second-layer lens is responsible for collecting sunlight at corresponding time. So sunlight with different incident angles in daytime passes through two-layer lenses that refracted to light pipe effectively.
We simulate the concentrating performance of the concentrator and only light pipe under real solar radiation in the summer solstice, vernal equinox, and winter solstice in Taipei city, Taiwan. According to the simulation results, the concentrator in this paper can provide steady luminous flux in daytime for kinds of lighting application.

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