Abstract
In this study, an optical design of the high power light emitting diode (HP LED) for illumination is proposed. A simplified structure of the LED that can use the lens to replace the reflector cup is designed. Therefore, the fabrication cost can be reduced. According to this design concept, a design method of the optical lens is developed. Based on the proposed method, an optical lens of the front-emitting HP LED to obtain a uniform illumination, and reduce the injured of the glare is designed. An optical model is used to obtain the overall point data of the lens profile by mathematics and geometrical optics base on the optical requirement. Either the straight lines or curves are used to draw the lens profile, and then rotate around the central axle to create the 3D optical model. In addition, the several lenses with same form but different scale are analyzed to find the optical properties of each lens in order to select a suitable size of the lens. The emission pattern of the lens is used to adjust the lens profile and each lens profile is analyzed to search the optimization lens profile by the uniformity of the illumination. Finally, an optical lens model with excellent illumination uniformity is found.