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 fabrication
and propose a criterion for the optimal design of side mirrors and rear-view mirrors. This criterion is that the root-mean-square of the difference between the two principle curvatures on the mirrors shall be minimum. Finally,we propose a new design for the shape of a mirror with a wide viewing angle. It is a non-spherical mirror and, in order to reduce the image distortion, the variation of the curvature along the curve on its surface is a constant. We also point out how to produce this mirror in practice.