freeadj.自由的；免费的；畅通的；没有…的；未使用的；空闲的；随意的v.释放；使自由；使摆脱；解除；使可用于(某目的)adv.免费地；自由地free oxide游离氧化物

1. Then the equation sets were solved by difference method to get the surface data of the free reflector.
   采用差分法求解微分方程组得到自由曲面反光器的面形数据。