With the improvement of precision in various fields, we present a new method for the measurement of the absolute distance of a remote target based on the laser interferometry technique. In this paper, we obtain the interference fringes change information (the distance information) with the help of laser scanning with different frequency. It does not require the target to move in the direction of measurement. We have done experiments to compare this new methods results with the results of RENISHAW interferometer. Its improved that the accuracy of distance measurement is 10-4~10-5 relatively.
High-precision frequency sweeping interferometry for absolute distance measurement using a tunable laser with sweeping range of 88 GHz