图1为半圆透镜的加工,原是将单块半圆透镜粘上火漆,上盘时将两块半圆透镜的弦面对成一近似圆透镜的形状,再贴置上盘,成盘精磨抛光。但当a、b两透镜进行胶合时,很难使中心偏C达到0.03mm的技术要求。有时中心偏虽然合格,但外圆柱面又会出现两块不齐的现象,因而造成大量报废。 Figure 1 is a semi-circular lens processing, the original semi-circular lens is sticky to the fire retardant paint, the disc will be two semicircular lens chord into an approximately circular lens shape, and then affixed to the disc, into a disk grinding and polishing. However, when a, b two lens gluing, it is difficult to make the center of the C to 0.03mm technical requirements. In some cases, although the center is partial, two cylindrical irregularities will appear on the outer cylindrical surface, resulting in a large amount of scrapping.