LED產業蓬勃發展，現今有許多傳統光源已經逐漸被LED所取代。在燈具方面，勢必不能直接套用。在照明方面，不同的環境，有基本的照度均勻度的要求，為了讓人處在更舒適的環境，降低眩光的影響，所以提昇照度均勻度格外重要。在本文，提供一個光源重新分配的概念，利用幾何光學的基本架構下，設計出能使照度均勻度提升的複合式多曲率透鏡，再將這些透鏡用光學模擬軟體使用光線追跡的方法來討論透鏡效果，搭配此透鏡能將均勻度從35.71%提升至76.17%。 此外，藉著提升透鏡的圈數，能將溢位的情況降低。

Light-emitting-diode (LED) sources have played a very important role in the future. Nowadays, there have many traditional sources gradually to be replaced by LED sources. In the illumination’s aspect, different environment had the basic illumination’s uniformity request. In order to let the human feel more comfortable in the lighting environment and reduce influence which dazzles from the worse design of lighting. Therefore, the promotion of illumination’s uniformity is an especially important key issue. In this article, we propose one effective design to improve the illuminated uniformity of LEDs with Lambertian radiation profile by inserting the lens with multiple-curvatures. The enhanced uniformity of LEDs is due to the concept of energy redistribution by well-controlled the direction of incident light under the geometrical optics theory. Ray tracing method is applied for simulation required. Finally, the illuminated uniformity is 76.17 % in the LEDs with multiple-curvature lens which is twice time compared to the conventional LEDs. Furthermore, the phenomenon of overload in the multiple-curvature lens is reduced by increasing the numbers of rings on the lens.

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