设计： 将口镜柄改为三棱状， 既便于握持， 又克服了易转动、滑脱的缺陷； 在口镜头端增设一个窥灯， 解决了治疗盲区之采光难题。结构原理： 三棱柄即口镜柄为三棱状柱体， 呈理想的几何稳固形。口镜柄中央空心(内置导线)， 近口镜头部逐渐缩细， 横截面为等边三角形。窥灯设 Design: The mouth mirror handle is changed to a triangular shape, which is not only easy to hold, but also overcomes the defects of easy rotation and slippage. The addition of a spy light at the end of the mouth lens solves the problem of lighting in blind areas. Structural principle: The triangular prism, which is a triangular prism, is ideally geometrically stable. The central hollow of the mouthpiece handle (with built-in wire), the proximal lens section is tapered, and the cross section is an equilateral triangle. Spectator design