作者：厦门欣锐仪器技术部  转载自：  发布日期：2008-5-15

徕卡迪士通距离测量是基于相位测量原理。激光二极管发射定义好波长的脉冲光和脉冲重复频率。
由于内部参考路径和外部测量路径的运行时间不同，徕卡迪士通接收到的目标反射脉冲光和内部参考路径接收到的脉冲光有相位偏差关系。这两个信号的相位偏差与仪器和目标的距离有着一定的比例关系。

The receivers convert the optical signals into electronic signals and the analog-digital-converters (ADC) of the micro controller convert them into digital signals. The built in micro controller calculates the phase difference between the reference signal and the measurement signal. If the phase difference is higher than 360°, for example 410°, then the micro controller would calculate a distance corresponding to 50°. To avoid such an error the pulse repetition frequency of the laser light pulses has to be reduced and a second measurement, a socalled coarse frequency measurement, has to be executed. Depending on the specified measurement range of the instrument various coarse frequencies have to be used to calculate the correct distance