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微光成像系统信噪比及图像探测特性研究 总被引:4,自引:0,他引:4
分析了电子轰击电荷耦合器件( EBCCD)微光成像系统的噪声源,建立了系统的信噪比模型,指出了在微光成像系统本身的增益和量子效率等性能确定的条件下,成像系统输出图像信噪比不仅仅与输入面照度有关,还与输入图像的空间频率有关,并通过实验得到了证明,指出了经典的图像探测方程(Rose方程)的不完善之处。 相似文献
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The accelerating burn in and screening method of processing 1 310 nm InGaAsP of laser diodes (LDs) is introduced. It is confirmed that the theory of burn in and screening is based on the second derivative minimum of burn-in curve, and the new testing method has been given, that is automatic current control (ACC) burn-in and automatic power control (APC) testing. This avoidably bring the errors of testing in only ACC or APC method, which need to monitor and control or test LDs power change by photo-detector (PD) at high temperature, and LDs or PDs must be into the same environment (PD will be burn-in at the same time). Through the experiment, the accelerating burn-in and screening condition of the devices has been confirmed: ACC, 200 mA, 100 ℃, 8 h. This raise work efficiency 12 times than Bellcore standard and save testing fee. 相似文献
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Existing methods of measurement MTF for discrete imaging system are analysed. A slit target is fre-quently used to measure the MTF for an imaging system. Usually there are four methods to measure the MTF for a discrete imaging system by using a slit. These methods have something imperfect respectively. But for the dis-crete imaging systems of under sampling it is difficult to reproduce this type of target properly since frequencies above Nyquist are folded into those below Nyquist, resulting in aliasing effect. To tackle the aliasing problem, a super resolution technique is introduced into our measurement, which gives MTF values both above and below Nyquist more accurately. 相似文献
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基于LabVIEW的复杂分布噪声信号的生成与控制 总被引:1,自引:0,他引:1
试验中有时需要复杂分布的噪声信号,而一般的信号发生器只能提供一种噪声分布的信号,往往不能满足要求。NT实现复杂分布噪声信号的生成与控制,本文基于LabVIEW开发平台和GPIB接口,采用通过VISA子函数控制具有存储功能的信号发生器产生和输出所需信号的方法,以达到目的。并以安捷伦公司的33220A函数/任意波形发生器为例详述了具体的编程和控制过程。实验表明,采用计算机控制任意波形发生器,提高了工作效率,可使其按需要产生输出复杂分布的噪声信号,拓展了仪器应用范围。 相似文献
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