为了在材料表面激光3维改性系统中有效地消除系统误差并提高系统精度，根据材料表面改性图形为填充图样的原理，采用3维扫描线重建算法对空间封闭曲线进行了激光半径补偿。经过交点计算及闭合检查，对空间3维数据进行重建，基于VC++平台实现了半径补偿算法，完成重建图形显示并控制系统完成材料表面激光3维改性实验。经理论分析及实验验证，重建后的3维图形补偿了0.07mm光斑直径距离，取得了与标准值更加接近的实验数据。结果表明，此种算法具有一般性，可有效消除系统误差并提高系统精度。

In order to eliminate systematical error and improve system precision effectively in 3-D material surface laser modification systems, according to the principle of filling lines in the surface modification area, based on the algorithm of 3-D scanning lines data compensation, laser spot radius compensation for 3-D close graphics was investigated. By calculation of intersection point and closure checking, 3-D graphic data can be reconstructed. Based on VC++ platform, compensation algorithm was realized, reconstructed graphics was displayed, and laser control for material surface modification was achieved. Through theoretical analysis and experiments, the graphics after compensation makes up the laser beam 0.07mm in diameter, close to the standard size. In conclusion, the algorithm is effective generally and can eliminate systematical error and improve system precision effectively.