抄録
Most metal frame spectacles are now made of titanium alloy. Recently, however, frames made of gum metal have started to be produced. Gum metal is a new material having a low Young's modulus, high strength and high elastic deformation. This report compares the mechanical characteristics of the full-rim and rimless spectacles made of gum metal on the market and the conventional titanium frames by using recent measuring and analytical techniques. Using the finite element method (FEM), the authors preformed detail analysis of the mechanical characteristics of these frames. Consequently, gum metal frames were found to fit slightly better than titanium ones. Irrespective of the material they are made from, however, rimless spectacles have greater risk of lens damage and require a structure that can effectively mitigate the temple opening force by the improvement of end pieces and hinges.
