一对１／４节距自聚焦棒透镜构成的准直系统通常存在三种装配误差：错位、间隔和倾斜，由此产生一定的附加耦合损耗。理论分析和数值计算结果表明，损耗与装配误差在小范围内近似呈平方递增关系，增幅与透镜聚焦参数有关。根据具体装配工艺选取合适的自聚焦棒透镜，能显著降低耦合损耗。 A collimation system consisting of a pair of 1/4 pitch autofocusing rod lenses usually has three types of assembly errors: misalignment, separation, and tilt, thereby creating some additional coupling loss. The theoretical analysis and numerical results show that the loss and the assembly error increase approximately squarely in a small area, and the increase is related to the lens focusing parameters. According to the specific assembly process to select the appropriate self-focusing lens lens, can significantly reduce the coupling loss.