PURPOSE: To design a mold capable of molding plastic moldings with high accuracy by providing an NC data preparation section machining a mold having a molded surface shape correcting resin shrinkage on the basis of shape regression formula obtained by a mold-shape correction section.
CONSTITUTION: A regression-curve arithmetic section 4 computing the regression curve of an aspheric lens and a mold on the basis of measured data displaying the shapes of the aspheric lens and the mold acquiired by a shape measuring section 3 capable of measuring the shape of the aspheric surface of a form tally serf (phonetic), a three-dimensional measuring machine, etc., is provided. The quantity of a resin shrunk at the time of the injection molding of the aspheric lens and the resin shrinkage-quantity correction shape of the mold are arithmetically operated by a mold-shape correction section 5 on the basis of the regression result of the aspheric lens and the mold obtained by the regression-curve arithmetic section 4, and NC data are prepared by an NC data preparation section 6 on the basis of an arithmetic result in the mold-shape correction section 5.
UEDA KATSUNOBU
KAIRIKU YOSHINORI
