《配装眼镜》标准有两个,GB13511-1992和1999,现在执行的是1999标准,代替了1992标准。在两个标准里同是5.4.1中有同样一个注:“镜片的光学中心应位于镜圈几何中心垂直方向上下3mm的范围内。“可是在1992标准中,对±0.25至±1.00D,要求光学中心垂直互差合格品≤5mm,优等品≤3.5mm,都超出了3mm的范围。于是,有人理解为应位于镜圈几何中心上下6mm的范围内。在1999标准中,对±0.25至±1. There are two “fitted glasses” standards, GB13511-1992 and 1999, which are now implemented as the 1999 standard, replacing the 1992 standard. In both standards the same is true for 5.4.1: “The optical center of the lens should be within 3 mm above and below the geometric center of the mirror ring.” However, in the 1992 standard, for ± 0.25 to ± 1.00D, Requirements of the optical center of each vertical difference between qualified products ≤ 5mm, premium products ≤ 3.5mm, are beyond the scope of 3mm. Thus, it is understood that should be located within the geometric center of the mirror 6mm above and below the range. For the 1999 standard, for ± 0.25 to ± 1.