非球面後視鏡曲面之最優化設計

The Optimal Design of the Non-Spherical Side Mirrors and Rear-View Mirrors

本文中說明一般業者通用的後視鏡製作過程，並提出一種判準來達到後視鏡鏡面的最優化設計，其是令鏡面上主要曲率差的均方根值為最小。依此判準，我們提出一種新的車輛後視鏡面設計，以有較廣視角。此鏡面不同於一般常用的球面狀後視鏡，其為非球面狀。同時，鏡面內曲率的變化為常數，使其能有較小的影像扭曲。我們並說明如何在實務上製作這類鏡面。

In this paper, we describe the generally adopted process of fabricationand propose a criterion for the optimal design of side mirrors and rear-viewmirrors. This criterion is that the root-mean-square of the difference betweenthe two principle curvatures on the mirrors shall be minimum. Finally,we propose a new design for the shape of a mirror with a wide viewingangle. It is a non-spherical mirror and, in order to reduce the imagedistortion, the variation of the curvature along the curve on its surface is aconstant. We also point out how to produce this mirror in practice.