激光调阻机F-Theta扫描镜头光学设计

摘要

Laser resistor trimming machine, whose precision depends on the optical performance of the scanning lens, is widely used in tuning the chip resistors. According to the practical requirements, two kinds of F-Theta lenses working in different wavelength (1 064 nm and 532 nm) are designed. The Fields of View (FOV) are ±28°and ±25°. The focusing spot diameter are about 30μm and 10μm. The final design result shows that the calibrated F-Theta distortions are both less than 0.1% and the energy utilization rate are nearly 90% which means that the focusing performances are close to the diffraction-limited. Both lenses can be exchanged and located conveniently on account of the simple and compact structures. The requirements of resistor trimming are satisfied well.%激光调阻机用于对片式电阻阻值进行微调，其调阻精度主要取决于扫描镜头的光学聚焦性能。根据实际使用需求，本文设计了两组不同工作波长(1064 nm和532 nm)的F-Theta扫描镜头，视场角分别为±28°和±25°；聚焦光斑直径分别为30μm和10μm。最终设计结果表明：两组镜头像散值在像差容限范围内，满足平像场要求；F-Theta相对畸变均小于0.1％；光能利用率达到90％以上；聚焦性能接近衍射极限。两组镜头结构简单紧凑，方便互换与装卡，能够满足激光调阻要求。