The requirements for electric propulsion systems suitable for scientific missions are becoming increasingly stringent. This includes, in particular, the reduction of the beam divergence and the alignment accuracy of the thrust vector. Therefore, a modular electrostatic lens module has been developed by using an ion trajectory simulation model which considers the ion produced space charge. The focus module can be mounted on an IFM Nano Thruster with equal side length of 100 mm and it works for the entire operation envelope without increasing the electronics complexity. Experimental beam diagnostics measurements and performance analyses are carried out on an IFM Nano Thruster laboratory model with and without attached focus module. The results show an improvement in thrust and specific impulse of up to 30%. In addition, the beam divergence half-angle is drastically reduced down to $<20^{\circ }$ half-angle and a high thrust vector accuracy of $<0.9^{\circ }$ is achieved. In addition, the focus module significantly reduces the droplet contamination angle. With this design evolution, the IFM Nano Thruster is becoming a suitable candidate for highly complex scientific missions, such as NGGM.

适用于科学任务的电力推进系统的要求变得越来越严格。这尤其包括减小射束发散度和推力矢量的对准精度。因此，利用考虑离子产生的空间电荷的离子轨迹仿真模型，开发了模块化静电透镜模块。对焦模块可以安装在等边长为 100 的 IFM Nano Thruster 上 mm，它适用于整个操作范围，而不会增加电子设备的复杂性。实验光束诊断测量和性能分析是在带有和不带有附加聚焦模块的 IFM Nano Thruster 实验室模型上进行的。结果显示推力和比冲提高了 30%。此外，光束发散半角大幅降低至$<20^{\circ }$半角和高推力矢量精度$<0.9^{\circ }$已完成。此外，对焦模块显着降低了液滴污染角度。随着这种设计演变，IFM 纳米推进器正成为高度复杂的科学任务的合适候选者，例如 NGGM。