Methods of Determining Optimal Fitting Spherical Surface for Off-Axis Aspheric Optics Finishing
Most present methods of determining optimal fitting spherical surface for rotationally symmetrical aspheric optics are either unsuitable for off-axis optics or unable to guarantee the condition of positive removal (distances from points on desired concave aspheric surface to the center of fitting sphere are all longer than radius of sphere while distances from points on desired convex aspheric surface to the center of fitting sphere are all shorter than radius of sphere).To surmount thetwo problems,this paper proposes three methods of determining starting spherical surface in finishing/polishing aspheric optics:method of using the function oflsqlin provided in Matlab,the modified method of least squares and the method of exhaustive search of tangent spheres.An example is presented to validate the three methods and to demonstrate all of them gain some advantages over conventional one by comparing attributes (normal deviation distribution,maximum normal deviation,volume of material to be removed,rms of normal deviation distribution,etc.) of their optimal fitting spheres against those of sphere obtained by utilizing conventional method.
off-axis aspheric surface optimal fitting spherical surface modified method of least squares tangent spheres exhaustive search
XU Xing Zhu YUN Zhang YU Yue Wang ZHI Jing Feng
Department of Precision Instruments and Mechanology,Tsinghua Univ.,Beijing 100084,China
国际会议
沈阳
英文
450-456
2012-07-27（万方平台首次上网日期，不代表论文的发表时间）