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实用化的光束质量测量系统 总被引:5,自引:0,他引:5
文中报道了一个基于CCD和计算机的HSH-I型光束参数及衍射极限倍数因子M^2测量系统,对测量方法、软硬件组成和来源进行了讨论,并给出了实际测量的结果。 相似文献
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在用频谱分析仪测量信号时,正确地设定分辨率带宽(RES BW),是减少测量误差、捕捉两个十分邻近和相对弱小信号的关键。我们知道,分辨率与频谱仪中频滤波器(IF滤波器)的带宽有关,带宽越窄,分辨率越高。除了滤波器的带宽之外,形状因数(shapefactor)、滤波器类型、剩余调频(residual FM)和噪声边带也是设定分辨率带宽时应考虑的因素。下面,我们将依次分析每一项。首先,我们注意到,测试信号在频谱分析仪显示屏上不可能显示为无限细的线,它本身有一定的宽度。当调谐通过信号时,其形状是频谱分析仪自身分辨率带宽(IF滤波器)形状的显示。这样,… 相似文献
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使用最新一代的扩散冷却型Slab CO2激光器对低碳钢进行了激光深熔焊接实验研究。Slab CO2激光器具有高光束质量。实验主要通过改变焦点位置获得不同离焦量下激光深熔焊接焊缝成型,分析并讨论了激光光束质量和焦深对焊接结果的影响。 相似文献
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The author's objective for this work was to find the least expensive motor with the best linearity and repeatability for a rotating and scanning mirror used in a hematology analyzer instrument. The design criterion was a minimal acceptable error of 3% for the worst segment length. The galvanometer and the floppy disk motor were selected as the best candidates for further testing. All testing was repeated with ten additional floppy disk motors, and similar results occurred. In addition, life testing and temperature testing were conducted again with no significant changes. A stable oscillator circuit controls the speed of the floppy disk motor. Even if the absolute motor speed changed slightly over temperature or time, as long as it stayed uniform during the scans, the calculated segment length values did not change. The floppy disk drive motor with a mirror mounted on the shaft of the motor was the best candidate. The motor's speed came close to the desired scanning speed 相似文献
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文献[1~2]报导了等效光束质量因子M~2_e<1的激光束,并称之为"超衍射极限"的光束.本文模拟计算出一种M~2_e<1而M~2>1的激光束,从而说明M~2_e<1与M~2<1并不"等效".M~2_e<1的激光束其M~2是否也<1是一个尚待澄清的问题。 相似文献
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介绍一个组合式光学多道分析仪系统的结构,以及它在激光束光谱的结构、远场分布、方向性等参量的实时测量和染料吸收系数直接测量上的应用。 相似文献
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