1996 Volume 53 Issue 6 Pages 345-351
The purpose of this work is to investigate experimentally some effects of molding conditions on the lens surface shape. Several kinds of spherical meniscus lenses were molded with poly (methyl methacrylate). The deviation of the lens surface from the mold surface, Δz, was precisely measured by a contact-type measuring instrument. Δz was divided into two factors, the approximate spherical component Δf and the component Δg that is the deviation of Δz from Δf. The ratio α of RL to RM, where RL is the approximate radius of lens surface and RM is that of the mold surface, was calculated. The Δf value widely varied depending on molding conditions, but Δg was only slightly influenced. Therefore, the variation of Δz with molding conditions is apparently dominated by that of Δf. The α value for one sideof the lens surfaces is proportional to α for the other side. The correlation equations for α for the two sides were shownin each individual lens. A deformation model of the lens was also proposed.
