In order to decrease the impurity absorption bands of Ge-Se-Te chalcogenide glasses in IR region. Three different kinds of deoxidants including Mg(magnesium), Al(aluminium) and Ca(calcium) were chosen. Properties measurements including density, Vis-NIR and infrared (IR) transmission spectra were adopted to analyze the relationship between impurity absorption bands and deoxidants. The concentrations of impurities in glass samples with different content of Mg were calculated by method of optic spectra. The results show that Mg is a better choice as deoxidant for chalcogenide glasses compared to Al and Ca. The values of main impurity concentration decrease from 4417.833 to 0 ppmw for Ge-O and from 55.236 to 0 ppmw for Si-O with increasing content of Mg, respectively. At least 200ppm Mg is needed to minimize the main absorption bands in IR region and G5 glass incorporated with 400ppm Mg has minimum concentration of impurities which means that it possesses the optimal transmission properties.

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An actual packaging structural of high power three-chip white LED lamp is designed. The highest temperature of LED chip is 111.2°C, and the temperature range of heat sink is 72.6°C～73.8°C by finite element method (FEM). The respective temperature of lead frame and heat sink are 76.0°C and 71.0°C, which are measured by the thermocouples experiment. Based on the consistency between simulation results and experiment data, considering the steady temperature distribution of the lamp and heat transfer theory, several optimization methods are proposed. The effects of copper pad dimension, solder paste area and natural convection coefficient on the temperature field distribution are calculated.

The high accuracy modeling is a prerequisite to study UTC-PD matching circuit design and power combining. This paper presents the high accuracy modeling method of UTC-PD photodiode. The measured frequency response curve of photoelectric conversion was used as a benchmark, and the model of the equivalent circuit was modified consistently in order to make the frequency response curve of the model fit the measured frequency response curve. This method addressed effectively the modeling issues of UTC-PD photodiode.

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