取样率是高能激光装置中衍射光栅的一个重要技术指标，针对取样率测量中存在的泊松噪声、杂散光干扰以及探测器不一致误差的影响，提出了一种组合噪声处理方法。对测量环境及探测器输出的统计特性进行了分析，通过统计规律求平均的方法，降低了泊松噪声对测量结果的影响；通过直方图去噪的方法，对杂散光的影响进行了抑制；通过互标的方法，减少了由于探测器不一致问题所带来的干扰。结果表明：取样率测量的相对平均偏差为0.297%,标准偏差为1.22%，满足取样率测量相对平均偏差优于0.4%，测量标准偏差优于2%的指标要求。为衍射光栅取样率测量的噪声处理提供了新的技术手段，并已在大口径衍射光栅综合诊断平台上得到验证和应用。

The sampling rate is an important technical indicator of diffraction grating in high-energy lase device, and for the Poisson noise in the sampling rate measurement and stray light interference , the probe is inconsistent and the combination of noise processing method is proposed. The measurement environment and the statistical properties of the detector output are analyzed by statistical laws averaging methods to reduce the Poisson noise effect on the measurement results. Denoising by the histogram method, the influence of stray light is suppressed. By mutual targets, the interference caused by the inconsistencies of detector is reduced. Test results show that the sampling rate measurement relative average deviation is 0.297% and measurement standard deviation is 1.22%. The sampling rate measurement relative average deviation is better than 0.4% and measurement standard deviation is better than 2%, which meet all requirements for sampling test. The method provides a new noise suppress technical means for the measurement of the diffraction grating sampling rate and has been applied and verified in a large aperture diffraction grating comprehensive diagnosis platform.