Design Of A Laser Wavelength Measurement System Based On Laser Synthetic Wavelength Interferometry

High frequency stabilized reference laser is an important guarantee for the realization ofthe laser interference measurement. With the advent of high frequency stabilized laser, indirectmeasurement of various physical quantities became possible, which use the laser wavelength asa ruler. The laser wavelength measurement has become more and more important in many fields,such as basic science, accurate measurement, metrology, information science, communication,astronomy. The existing methods of laser wavelength measurement have low measurementprecision, complex optical structure and poor immunity. To solve these problems, a laserwavelength measurement system based on laser synthetic wavelength interferometry isproposed which has high measurement precision.In this thesis, the advantages and disadvantages of various methods of measurement havebeen summarized based on the analysis of domestic and international laser wavelengthmeasurement systems. The laser wavelength measurement schemes based on the singlefrequency orthogonal linear polarized laser and the laser synthetic wavelength interferometryhave been proposed. Because of the precision of the wavelength measurement scheme based onthe single frequency orthogonal linear polarized laser relies on the guide rail positioningaccuracy, the wavelength measurement scheme based on the principle of laser syntheticwavelength interferometry is adopted at last. The performance requirements and selectioncriteria of the important optical devices have been given. The measuring range of thewavelength measurement system has been analyzed. Theoretical analysis shows that themeasuring range of the system depends on the minimum and maximum displacement of thereference arm guide rail. The optical principle of PBS is analyzed theoretically. Nonlinearityerror of the laser wavelength measurement system has been analyzed based on the opticalseparating principle of PBS. And the simulation results show that the synthetic wavelengthuncertainty caused by the nonlinear error is less than1.67×10-3. The chip selection and thesoftware development of the wavelength measurement system have been completed. Finally,the wavelength measurement system based on the laser synthetic wavelength interferometry hasbeen realized.In order to verify the feasibility of the constructed laser wavelength measurement system, the following experiments have been carried out:(1) wavelength measurement system stabilitytest: the experimental results show that the uncertainty of the synthetic wavelength is7.17881×10-4;(2) single wavelength measurement comparison experiment: wavelengthmeasurement results are consistent with the wavelength of the frequency stabilized lasers, thewavelength measurement uncertainty is10-8;(3) the comparison experiments with Bristolwavemeter: the wavelength of a tunable laser is measured and the experimental results showthat the proposed wavelength measurement system is feasible, wavelength measurementuncertainty is10-6.