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This paper describes a novel finite element thermal analysis model for an AlGaInP-LED micro-array device. We also conduct a transient analysis for the internal temperature field distribution of a 5×5 array device when a 3×3 unit is driven by pulse current. In addition, for broader applications, a simplified thermal analysis model is introduced and its accuracy is verified. The internal temperature field distribution of 100×100 units is calculated using the simplified model. The temperature at the device center reaches 360.6 °C after 1.5 s. In order to solve the heat dissipation problem of the device, an optimized heat dissipation structure is designed, and the effects of the number and size of the heat dissipation fins on the thermal characteristics of the device are analyzed. This work has been supported by the Young Scientists Fund of the National Natural Science Foundation of China (No.61204055). E-mail:gaofl@jlu.edu.cn 相似文献
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在模式融合的生物特征识别的基础上,提出了防伪的手指静脉和指纹复合信息识别系统模型,来解决指纹识别系统安全性和问题。建立了手指静脉识别新方法。首先对获取的手指静脉图像进行二进制小波变换,将图像信息转换为一系列的小波系数,此系数中包含背景以及采集时的噪声,通过软阈值去噪,从小波系数中消除噪声信号系数,用消噪后的小波系数重构手指静脉信号,重构后的图像作为特征图像。由于静脉信息相对较少,因此可采用比较准确的模板匹配。 相似文献
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测量了大功率InGaAsP/GaAs量子阱半导体激光器在五十分之一阈值电流下的电压低频噪声功率谱密度.实验结果显示,激光器的低频电噪声呈现1/f噪声,在不同的偏置电流范围内,1/f噪声幅度随电流的变化关系不同,整体上随偏置电流的增大而减小,实验中并未发现g-r噪声.结合低偏置电流时激光器动态电阻的大小,给出了1/f噪声的模型,分析了在低偏置电流下的1/f噪声主要来自有源区和漏电电阻,其幅度的大小及其随偏置电流的变化趋势与激光器的可靠性有密切的关系. 相似文献
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A 300 μm×300 μm light emitting diode (LED) chip is divided into nine 80 μm×80 μm units with 30 µm spacing between adjacent ones. After arraying, the total saturation light output power and the maximum injection current are enhanced by 5.19 times and nearly 7 times, respectively. In addition, the test results demonstrate that the illuminance uniformity on the receiving surface reaches the optimum when the spacing between the arrays is equal to the maximum flat condition. The larger the number of arrays, the greater the area with uniform illuminance on the receiving surface. 相似文献
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介绍了Visual C++.NET环境下用SCPI语言实现对大功率直流电源SM35-45的控制。通过获取列阵器件的V-II、dV/dI-I、P-I、dP/dI-I特性曲线,对其质量和可靠性进行了测试。测试结果表明:该电源的纹波系数、稳定度等参数能满足激光器列阵的驱动要求,所获取的评价激光器可靠性的结特征参量m、反映结的完整性及载流子泄漏的参量b等参数准确可靠,而且该测试系统有较好的稳定性。 相似文献