【摘要】 为了获取激光束的准确束宽值,模拟了基模和高阶模的高斯光束以及CCD噪声,并根据国际标准ISO 11146规定的二阶矩算法计算激光束宽。为减小CCD噪声对测量结果的影响,通过改变积分项以及积分范围,对积分结果进行分析,提出了一种新的自适应方法来确定理想积分范围大小,从而获取准确束宽值。这种自适应方法对CCD噪声有较好的鲁棒性,并可以根据指定精度来确定参与积分的窗口大小范围。利用实际CCD采集系统进行了半导体激光器的M2因子测量实验,利用该自适应方法确定积分范围,计算激光束宽,并进行曲线拟合求得激光束的M2因子。结果证明了该种方法的可行性。更多还原

【Abstract】 To obtain the correct beam width value,CCD noise,lowest and higher-order Gaussian laser beam are simulated.According to ISO 11146 standard,laser beam width is calculated in second-order moment arithmetic.To mitigate the influence of CCD noise on measuring result,integral part and integral area are varied to get different results.Based on the analysis of these results,a new adaptive algorithm is presented.The appropriate integral area could be obtained to calculate right beam width value.The adaptive algorithm could abide heavy CCD noise,and define the corresponding integral area according to requested precision.Finally,the experiment to measure the M~2 factor of the semiconductor laser beam with CCD camera system is performanced.The adaptive algotithm is used to define the integral area and calculate the beam width.Based on the result,the M~2 factor of the laser beam is obtained by curve fitting.The final result demonstrates the feasibility of the adaptive algorithm.更多还原