The spot position and size of a proton beam are critical parameters in the scanning dose delivery system. They need to be validated efficiently and accurately. But the traditional methods work poorly in some non-ideal cases. In this study, we develop effective means for the position verification algorithm, including the student’s t distribution fitting algorithm, the Slope method, as well as the improved Gaussian fitting algorithm. And we verify the accuracy of them experimentally. That is several times higher than the one of the traditional fitting algorithms. The root mean square error (RMSE) of the improved Gaussian fitting algorithm is less than 0.2 mm as the signal-to-noise ratio (SNR) is higher than 30 dB even when a damaged strip exists around the beam spot. Furthermore, we implement the proposed Gaussian fitting arithmetic and the Slope method in Field Programmable Gate Arrays (FPGA) to test their efficiency. If the clock frequency of the chip with enough calculation resources is higher than 10 MHz, the computing time can be less than $6\mathrm{\mu }\mathrm{s}$ and $4\mathrm{\mu }\mathrm{s}$, respectively. Finally, we conduct a simulation experiment. The result shows that RMSE of the proposed three methods are all less than 0.3 mm as the SNR is around 25 dB.

质子束的光斑位置和大小是扫描剂量输送系统中的关键参数。他们需要有效和准确地进行验证。但是传统方法在某些非理想情况下效果不佳。在这项研究中，我们开发了有效的位置验证算法，包括学生的t分布拟合算法，Slope方法以及改进的高斯拟合算法。并且我们通过实验验证了它们的准确性。这是传统拟合算法之一的几倍。改进的高斯拟合算法的均方根误差（RMSE）小于0.2 mm，因为即使在束斑周围存在损坏的条带时，信噪比（SNR）也高于30 dB。此外，我们在现场可编程门阵列（FPGA）中实施了拟议的高斯拟合算法和斜率方法，以测试其效率。如果具有足够计算资源的芯片时钟频率高于10 MHz，则计算时间可以小于$6\mathrm{\mu }\mathrm{s}$ 和 $4\mathrm{\mu }\mathrm{s}$， 分别。最后，我们进行模拟实验。结果表明，由于信噪比约为25 dB，因此三种方法的均方根误差均小于0.3 mm。