Absolute distance measurement using cross correlation interferometer with a repetition rate multiplication frequency comb

Abstract

In this paper, the Fabry-Perot etalon is used to multiply the repetition rate of the fiber optical frequency comb. The repetition rate is amplified from 250 MHz to 10 GHz, and the corresponding pulse interval is reduced from 1200 mm to 30 mm. For the pulse cross correlation ranging method, the repetition rate multiplication can greatly reduce the length requirement of the scanning reference arm. We analyze in detail the principle of cross correlation interferometry based on repetition rate multiplication frequency comb. A numerical mode of the function is comprehensively established. The basic parameters of optical source and Fabry-Perot cavity for the influence of filtered optical spectrum and cross correlation fringe are analyzed through the numerical simulation. The multiplied frequency comb is utilized for absolute ranging with the help of a pulse cross correlation method. By comparison, our result differs from the result obtained by a conventional counting interferometer only by 4 μm for distances up to 210 mm.