LED结温度对其光输出稳定性影响的研究.doc

本科毕业设计(论文) 题目： 院（系） 光电工程学院 专 业 测控技术与仪器 学 号 070103111 班 级 070103 姓 名 马 鹏 导 师 董 威 2010年 LED junction temperature on the stability of light output Abstract Recently, the Light-emitting Diode is the hot topic in the research field of lighting technology. With its latent disadvantages of high efficiency, long-lasting longevity, pure monochrome property, solid state and environmental protection, it has gained more and more attention from all over the world. Several developed countries in the world have established the schema of their own countries in order to strongly speed up the development of the light-emitting Diode. In this case, the technology of light-emitting Diode has been developed rapidly. As the main indicator of LED， the lighting efficiency, at present，in the commercial product can be reached to 100lm/w. And in the laboratory it can be much higher. Therefore, the application field of Light-emitting Diode has gradually been used to commercial lighting field from the old display field and signal field. However, the LED is different from traditional light source greatly. Especially, its lighting efficiency is always influenced by the temperature. The rise of temperature can lead to the decrease of lighting efficiency. The purpose of this subject is to research how temperature affects the stability of LED and design an experiment to measure the temperature and luminous flux of LED. The designing measurement system measures the temperature and luminous flux by the photoelectric sensor and temperature sensor. Signal magnifying circuit processes the transmitted signals. Then MCU gathers and displays these signals. According to the experimental measurements and the analysis of data, it is concluded that the rise of temperature can cause the decrease of luminous flux. Key words: light-emitting diode; junction temperature; lum