光学自由曲面误差评定中匹配方法的研究

研究了光学自由曲面轮廓误差评定中被测曲面和设计曲面的匹配方法。在曲面中心重合和近似法矢重合的基础上,提出了五点预定位法,即先定义曲面中心,然后利用搜索的方法得到相互间距离最大的4个角点,通过这5个点的匹配实现曲面的预定位。在精调整中,提出了二次优化方法,即综合运用最小二乘法和最小条件原则进行曲面的高精度匹配,并进行了仿真实验。实验结果表明,匹配精度可达纳米级。最后通过一个非球面实测实验,证明了算法的有效性。

Study of matching methods for error evaluation of optical free-form surface

The matching methods between measuring surface and design surface were studied for the profile error evaluation of free-form surface. Based on the matching together of both center points and normal vectors of measuring surface and design surface, a pre-position method by five feature points including center point and four corner points was put forward to achieve better preliminary matching. The dual optimization method integrating the least square method and the least condition principle was presented for the accurate positioning. The results show that the matching accuracy can achieve the nanometer level. At last, an actual test of aspheric surface proves the validity of methods.