摘要为满足后顶焦度高精度测量需求，提出了一种基于激光差动共焦技术的后顶焦度测量方法，研制了一套测量系统。该系统将激光差动共焦技术的精密定焦性能应用于后顶焦度测量，显著地提高了定焦定位能力，利用干涉测长技术测量相应偏离距离，最终实现后顶焦度的精密测量。分析了测量装置的设计思路和测量精度的影响因素。理论分析和实验结果表明，该系统测量精度可达0.03 m -1。
Abstract：A new vertex-power measurement method based on laser differential confocal technique is proposed for the demand of high-precision back-vertex-power measurement. A vertex power measurement system is built up. This system takes advantage of outstanding focusing ability of laser differential confocal system to improve the positioning accuracy, and uses the interferometer to measure the distance from the origin and finally gets the results by means of conversion of the formula. The component design specifications and influence factors are analyzed. Theoretical analysis and experimental results show that the measurement error of the method is about 0.03 m-1.
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2014, Vol. 35 
