A Novel Temple Clamping Force Measurement Method for Eyeglasses Design

Abstract

The temple clamping force is an important factor affecting the fit and comfort of most eyeglasses. The temple height is usually very small (1.0~6.0 mm) and the clamping force is very low (0.0~1.0 N). However, the diameters of the effective area of available force sensors are usually larger than the temple height, and their lowest measurable force is sometimes larger than the clamping forces. This causes difficulty in measuring the clamping force using force sensors. Hence, we proposed a novel temple clamping force measurement method for eyeglasses, which only uses a digital tension meter. In this method, the displacement of the ear attachment points (EAPs) at the temple was computed based on the static and wearing expanded lateral distance of EAPs; and then the tensile force was measured based on the temple displacement by using a digital tension meter. The method has been applied to investigate the relationship between the measured clamping forces and the perceived fit scores of the temples. The experimental results are consistent with the previous report, which demonstrates the reliability of our proposed method.