本文介绍一种低成本线性保罗阱演示实验装置的制作方法.利用霓虹灯变压器作高压电源，用4根不锈钢圆柱作电极，得到交变的类四极电场.将带电孢子粉撒入电极包围的区域，带电量合适的孢子会被交变电场俘获.用激光照射，可以清楚观察到粒子局域化的运动轨迹.利用Matlab采用简化的电势模型对保罗阱的电势分布进行了数值计算，结合粒子所受到的重力、电场力和空气阻力等对粒子运动轨迹进行模拟，并估算出粒子所带的电荷量.

 In this paper a low-cost linear Paul trap demonstration device is introduced. Using a neon lamp transformer as high voltage power supply and four stainless steel cylinders as electrodes, an alternating quadrupole electric field can be obtained. When charged sporangium powder is sprayed into the region surrounded by the electrodes, sporangium with suitable charge can be captured by alternating electric field. Illuminated by a laser beam, localized trajectories of the captured particles can be clearly observed. The electric potential distribution of Paul trap is numerically calculated by using a simplified electric potential model in Matlab, and the particle trajectory is simulated by analyzing the gravity, electric field force and air resistance of the particle. The charge of the particles is also estimated.