自动焦度计定量计算式的研究

Quantitative Formula for Automatic Focimeter

首先对测量眼镜镜片顶焦度的光学系统进行分析.其次,根据棱镜效应的基本理论,推导出被测镜片的球镜顶焦度、柱镜顶焦度和柱镜轴位的计算式.该计算式表明,在镜片光学中心确定的情况下,只要探测到观察屏上2个小孔的落点位置坐标值,就可得到被测镜片的上述3个光学参数值.最后运用Zemax软件仿真测量了2个散光镜片,证明了这个计算式的可靠性.

The optical measurement principle of ophthalmic lenses＇ vertex power was analyzed. The quantitative formulas for spherical power, cylinder power and cylinder axial angle of the lens under test were derived based on the theory of prism effect. The formulas show that in the condition of fixed optical center, the above three optical parameters of the lens can be measured from detecting the coordinate values of two light spots of holes on the observation screen. The reliability of the formulas was further proved by simulations of one positive and one negative astigmatic-power lenses.