A mold with which a molded product in a desired shape with an aspherical
curved surface is molded can be designed with high precision by
correcting shape deformation of the molded product molded from the mold.A
mold 10 in which use surfaces 16 of an upper mold 11 and a lower mold 12
are formed to be design curved surfaces of the optical lens in a
spherical shape is prepared. A curved surface shape of the optical lens
molded from the mold is measured, a measured value is approximated by an
equation (1) which is an equation of an aspherical surface and a curved
surface of the molded optical lens is specified as an aspherical surface.
Information corresponding to an error between the curved surface of the
optical lens specified by the equation of the aspherical surface and the
above-described design curved surface is compiled into database for each
of characteristics of the optical lens as correction information for
molding the optical lens of which curved surface is in the spherical
shape. By using the correction information compiled into database, design
values of the use surfaces in the upper mold and the lower mold of the
mold with which the optical lens of which curved surface in the
aspherical shape is molded are corrected to design
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