In this paper,we present a phase multiplication algorithm(PMA)to obtain scalable fringe precision in laser self-mixing interferometer under a weak feedback regime.Merely by applying the double angle formula on the sel...In this paper,we present a phase multiplication algorithm(PMA)to obtain scalable fringe precision in laser self-mixing interferometer under a weak feedback regime.Merely by applying the double angle formula on the self-mixing signal multiple times,the continuously improved fringe precision will be obtained.Theoretical analysis shows that the precision of the fringe could be improved toλ/2^(n+1).The validity of the proposed method is demonstrated by means of simulated SMI signals and confirmed by experiments under different amplitudes.A fringe precision ofλ/128 at a sampling rate of 500 k S/s has been achieved after doing 6 th the PMA.Finally,an amplitude of 50 nm has been proved to be measurable and the absolute error is 3.07 nm,which is within the theoretical error range.The proposed method for vibration measurement has the advantage of high accuracy and reliable without adding any additional optical elements in the optical path,thus it will play an important role in nanoscale measurement field.展开更多
基金supported by the Natural Science Foundation of Fujian Province(No.2020J01705)the School Foundation of Jimei University(No.C150345)。
文摘In this paper,we present a phase multiplication algorithm(PMA)to obtain scalable fringe precision in laser self-mixing interferometer under a weak feedback regime.Merely by applying the double angle formula on the self-mixing signal multiple times,the continuously improved fringe precision will be obtained.Theoretical analysis shows that the precision of the fringe could be improved toλ/2^(n+1).The validity of the proposed method is demonstrated by means of simulated SMI signals and confirmed by experiments under different amplitudes.A fringe precision ofλ/128 at a sampling rate of 500 k S/s has been achieved after doing 6 th the PMA.Finally,an amplitude of 50 nm has been proved to be measurable and the absolute error is 3.07 nm,which is within the theoretical error range.The proposed method for vibration measurement has the advantage of high accuracy and reliable without adding any additional optical elements in the optical path,thus it will play an important role in nanoscale measurement field.
